JP2014511254A - Recovery of phosphorus from hydrothermal treatment of biomass - Google Patents

Abstract

  Biomass-based feedstock is processed under hydrothermal treatment conditions to produce a hydrocarbon liquid product and a solid portion. The solid portion can include a portion of phosphorus from the biomass feedstock. The amount of phosphorus in the solid portion can be increased for a biomass feedstock by adding a polyvalent metal to the feedstock. The phosphorus from the solid portion can be recycled for further use, such as for the growth of additional biomass.

Description

(Field of Invention)
The present invention relates to hydrothermal treatment of various types of biomass, such as algae, for producing hydrocarbon products such as distillate fuel.

(Background of the Invention)
Conventional production of fuels and lubricants remains the mainstream conversion (or conversion) of mineral (or mineral) petroleum feedstock into the desired product. In order to supplement and / or replace conventional sources with renewable forms of energy, various problems must be overcome.

  An alternative to conventional fuels and lubricants is to produce comparable fuels and lubricants based on biomass. One advantage of biomass-based fuels is that the resulting fuel product may be compatible with existing infrastructure and technology. Ideally, biomass-based fuels and lubricants can be used in an “easy-to-replace” manner instead of conventional products, allowing the use of renewable products without the need to modify existing equipment Will be.

  One option for processing biomass-type raw materials is hydrothermal treatment. Hydrothermal treatment involves exposing raw materials to water under high temperature and high pressure conditions. U.S. Pat. No. 6,057,836 provides an example of this type of process. This patent describes a process for converting biomass into a hydrocarbon mixture using near-critical or supercritical water. This process can be used for various initial biomass feedstocks. The biomass is treated at a pressure of 200 bar (20 MPa) to 500 bar (50 MPa) and at a temperature of 320 ° C to 500 ° C. The atmosphere in the reactor is described as non-oxidizing and is included in the case with hydrogen. About 4 hours is stated as a preferred processing time. Hydrothermal treatment is described as producing a “petroleum-like liquid” that appears to contain a significant portion of aromatic and polymer species, as well as some soot and / or carbonization residues. This description states that some metals present in the biomass feedstock, such as Ni or Fe, can change the type of product produced. This description also states that the metal can be used to simplify the components of the product mixture or to remove unwanted compounds. The only metal specifically mentioned as an additive is Cu metal for removal of sulfur compounds such as thiophenes. Nitrogen compounds are not provided as examples of suitable metals, but have been identified as other products that can be removed by precipitation with metals. From this description it appears that the additive metal used is a "reduced metal" rather than an oxidized metal.

  Patent document 2 of the PCT publication provides another example of biomass processing under supercritical conditions. This application describes the treatment of wet biomass, such as algae or water hyacinth, to produce gaseous hydrocarbons and hydrogen. The conversion conditions include contacting the biomass with water under supercritical conditions, defined as having a temperature greater than 374 ° C. and a pressure greater than 22.1 MPa. This conversion is carried out in the presence of a carbon-based catalyst, such as high surface area charcoal or activated carbon. This process is described as providing fast, substantially complete gasification of organics in the feedstock (or feedstock or feedstock).

US Pat. No. 6,180,845 International Publication No. 96/30464 Pamphlet

(Summary of the Invention)
In one embodiment of the present invention, a method for hydrothermal treatment of biomass is provided. The method introduces a biomass feedstock (or feed or feed) having a phosphorus content (or including phosphorus) and having a water: biomass ratio of at least 1: 1 into the reaction zone (or reaction zone). Process. This biomass feedstock can be hydrothermally treated under hydrothermal conditions effective to produce a multiphase product (or multiphase product). The multiphase product can comprise a solid portion comprising at least about 80% of the phosphorus content of the biomass feedstock. The multiphase product can be separated to produce at least a gas phase portion, a liquid hydrocarbon product, and the solid portion.

  In another aspect of the present invention, another method of hydrothermal treatment of biomass is provided. The method includes adding a polyvalent metal to a biomass feedstock having a phosphorus content (or containing phosphorus). This biomass feedstock can be contacted with water in the presence of the polyvalent metal under hydrothermal treatment conditions effective to produce a multiphase product. The multiphase product can comprise a solid portion comprising at least about 80% of the phosphorus content of the biomass feedstock. The multiphase product can be separated to produce at least a gas phase portion, a liquid hydrocarbon product, and the solid portion.

  In yet another aspect of the present invention, yet another method of hydrothermal treatment of biomass is provided. The method includes contacting an algae-containing biomass feedstock having a phosphorus content (or containing phosphorus) with water under hydrothermal treatment conditions effective to produce a multiphase product. The multiphase product can comprise a solid portion comprising at least about 80% of the phosphorus content of the algae-containing biomass feedstock. The multiphase product can be separated to produce at least a gas phase portion, a liquid hydrocarbon product, and the solid portion. The phosphorus from this solid part can advantageously be recycled (or circulated) into an algal growth (or propagation) environment.

1 depicts a reaction system suitable for performing a process (or method, process or step) according to an embodiment of the invention. 1 schematically shows a reaction scheme according to an embodiment of the present invention.

(Detailed description of embodiment)
Overview One of the problems in producing hydrocarbon products from various types of biomass may be the handling of non-carbonaceous products. In many cases, non-carbonaceous products can be considered as contaminants. Such pollutants can include sulfur-containing compounds and nitrogen-containing compounds formed from sulfur and / or nitrogen present in the biomass.

  For some biomass feedstocks, such as algae feedstocks or other feedstocks in which cellular material is included in the feedstock, phosphorus can also represent a notable part of the feedstock. However, unlike sulfur, it can be beneficial to view phosphorus as another product that is harvested (or recovered) from processing raw materials. Phosphorus can be incorporated into various cell structures, such as lipids used to form cell walls. Due to the importance of phosphorus in growing cellular structures, phosphorus can be a valuable input for the growth of biological organisms. The phosphorus required for the growth (or propagation) of biological organisms can account for significant costs in the growth process. Although phosphorus is not one of the major salable products formed from processing biomass feedstock to produce hydrocarbon products, the ability to effectively acquire and reuse phosphorus is important for hydrocarbon production. Process economics can be greatly improved.

  In various embodiments, a method for hydrothermal treatment of an algal feedstock (or other biomass-based feedstock) to produce a distillate boiling range product while allowing improved acquisition and / or recycling of phosphorus is provided. Provided. Hydrothermal treatment of the algae raw material is carried out in the desired boiling range while also removing at least some of the undesirable impurities in the distillate product, such as nitrogen impurities, oxygen impurities, unsaturated and / or aromatic impurities, metal impurities. The conversion of biomass into molecules having can be made possible. In various embodiments, hydrothermal treatment conditions can be adjusted and / or improved to facilitate phosphorus recovery. This can include increasing the total amount of phosphorus recovered relative to the amount of phosphorus in the feedstock. This can additionally or alternatively include increasing the phosphorus to carbon ratio in the phosphorus product formed during processing. The method for improving phosphorus recovery can include introducing a polyvalent metal, such as a polyvalent metal cation, into the reaction environment to form a metal phosphate. Another option is to select the amount of phosphorus recovered relative to the feed content and / or the temperature and / or length of time of the hydrothermal treatment that improves the ratio of phosphorus to carbon in the solids formed during the reaction. Can include.

  Algae can contain significant amounts of products such as triglycerides, fatty acids / alcohols, and isoprenoids that can be converted into valuable products such as transportation fuels and lubricating oils. However, many challenges exist when converting algae raw materials into usable products. One challenge is the recovery of desired hydrocarbon molecules from algae. An option for recovering hydrocarbon products from algae may be to use solvent extraction based methods. Unfortunately, some solvent-based methods require the use of algae sources that contain little or no water. Dehydration of the algae source to a degree sufficient to allow this type of solvent extraction can require high operating costs. Alternative solvent extraction methods can allow extraction from algae samples containing water. However, high cost processes usually remain because the solvent must be separated from the water, for example by distillation.

  As an alternative to solvent extraction, hydrothermal treatment can be used to extract hydrocarbon products from algae sources. Hydrothermal treatment has the advantage that it can be done without evaporating the water, which can reduce the cost of the process. However, another problem with using biomass to produce hydrocarbon products can be the presence of impurities in the biomass. Algal raw materials can have relatively high concentrations of molecules that can contain, inter alia, sulfur, nitrogen, oxygen, phosphorus, Group I metals, Group II metals, transition metals, olefinic groups, and aromatic groups. Due to the high impurity level, additional processing may be required before the hydrocarbon product from the non-contact hydrothermal treatment can be used in conventional processes.

Feedstock (or feedstock or feedstock)
In various embodiments of the present invention, an algal feedstock or another biomass-based feedstock can be treated using contact hydrothermal treatment. In one such embodiment, the ingredients typically can contain algae and water, and can optionally contain additional ingredients from another biocomponent source, where A biocomponent source is any source that includes and / or is derived from biological material, such as from plants, animals, microorganisms, algae, or combinations thereof. Additionally or alternatively, the feedstock can be a feedstock derived from a starting mixture containing algae and water, and can optionally contain a feedstock from another biocomponent source. Additionally or alternatively, the feedstock can generally be a biomass-based feedstock.

  Note that the water present in the algae (or other biomass) feedstock can include extracellular water and / or intracellular water. Intracellular water means water contained in the cell membrane of cells, such as algal cells. For algae raw materials, raw materials that appear to be relatively dry based on extracellular water content can still contain a significant portion of intracellular water. For algae whose cell walls have ruptured (eg, substantially dry / dehydrated algae), the algae source contains extracellular water (since the ruptured cell has no interior but only the exterior). It can only be a thing. For algae containing intracellular water, the calculation of the ratio of water to (dry) algae shows how much of the algae weight, since intracellular water should be considered for the weight of water and not for the weight of dry algae. It is necessary to measure whether this part is due to intracellular water. As a clear example, the algal sample still has a water to algal ratio of about 1: 1 or more, for example about 2: 1 or more, due to the amount of intracellular water in the algae, without any extracellular water. I can do it. Thus, reference herein to the weight of algae means the weight of dry algae, excluding intracellular water.

  For ingredients that contain at least algae and water, the algae content of the ingredient is at least about 5% by weight, such as at least about 10% by weight, at least about 20% by weight, at least about 25% by weight, or at least about 30% by weight. possible. Additionally or alternatively, the algae content of the feedstock can be about 50% or less, such as about 30% or less, about 25% or less, or about 20% or less. From a ratio point of view, the ratio of water to algae in the feedstock can be at least about 1: 1, such as at least about 2: 1, at least about 3: 1, or at least about 4: 1. Additionally or alternatively, the ratio of water to algae can be about 25: 1 or less, such as about 20: 1 or less, or about 10: 1 or less. In some embodiments, the algal content of the raw material relative to the amount of water can be based on practical considerations regarding the extraction of water from the algal source. Thus, in some embodiments, algae can be introduced into the reactor as a mixture or paste of algae and water. Additionally or alternatively, the dried form of algae can be introduced into the reactor along with sufficient water, for example, to achieve the desired ratio of algae to water.

  Algal oil or lipid can typically be contained in algae in the form of membrane components, storage products, and / or metabolites. Certain algal strains, especially microalgae such as diatoms and cyanobacteria, can contain proportionately high levels of lipids. The algal source for the algal oil can contain various amounts, eg, 2 wt% to 80 wt% lipid, based on the total weight of the biomass itself.

  Algal sources for algal oil can include, but are not limited to, unicellular and multicellular algae. Examples of such algae include red algae (rhodophyte), green algae (chlorophyte), heteroconte algae (heterokontophyte), tribophyte, gray algae (glaucophyte), chlorarachniophyte, Mention may be made of haptophytes, cryptomonads, dinoflagellum, phytoplankton, etc., and combinations thereof. In one embodiment, the algae can be of the class Chlorophycea and / or Haptophyta. Specific species include Neochloris oleoabundans, Scenedesmus dimorphhus, Euglena gracilis, and euglena calcipres. Nesium parvum, Nannochloropsis gaditiana, Tetraselmis chii, Tetraselmis tertiolect ), Dunaliella salina (Dunaliella salina), various species of Chlorella (Chlorella), and Chlamydomonas Lane Hart position (although Chlamydomonas reinhardtii) can be exemplified, but not limited to. Non-limiting examples of additional or alternative algal sources include Achnanthes, Amphiprora, Amphora, Ankistrodesmus, Asteromonas, Boequerolo, Boequero lo (Borodinella), Botriococcus, Bracteococcus, Chaetoceros, Carteria, Chlamygomonum, Chlorococcum, Chlorococcum, Chlorococcum, Chlorococcum, Chlorococcum Chloomonas, Chrysosphaera, Cricosphaera, Crypthecodinium, Cryptonas, Cycloella, E, Donaliella Emiliania, Eremosphaera, Ernodesmius, Euglena, Frankeaia, Fragilaria, Gloeothamito, Gloeothamito Locafeteria, Hymenomonas, Isochrysis, Lepocincris, locchinium, Rochnium, Np, N (Navicula), Neochloris, Nephrochloris, Nephroselmis, Nitzschia, Ochromonas, Oedogonium, oystis Streococcus, Pavlova, Parachlorella, Pascheria, Phaeodactylum, Fagus (Phagus), Platymonos ples Prototheca, Pseudochlorella, Pyramimonas, Pyrobotrys, Scenedesmus, Skeletonechoti, Spyroj one or more microalgae of the species Hococcus, Tetraselmis, Thalassiosira, Viridiella, and Volvox, and / or Agmenelum, Anabenoa, Anabenoa, Anacystis, Aphanizomenon, Arthrospira, Asterocapsa, Borzia, Calothris opium, Chamaeshiro opium Chroococcidiopsis, Chroococcus, Clinalium, Cyanobacteria, Cyanobium, Cyanocystosis, Cyanospis cyprus Cylindropermopsis, Cylindrospermum, Dactylococcopsis, Dermocarpella, Fischerella, Fremiella, Gayleitre eria, Geitlerinema, Gloeobacter, Gloeocapsa, Gloeothel, Halospiralina, Iyengarier (Lingbya), Microcoleus, Microcystis, Myxosarcina, Nodularia, Nostoc, Nostochopsis, Oscillaor , Formidium, Planktothrix, Pleurocapsa, Prochlorococcus, Prochloron, Prochlorothria v, Pseuroanauri, Pseudorubana v Schizothrix, Cytonema, Spirulina, Stanielia, Starria, Stigonema, Symproca, Cyneco, Cneco (Synechocystis), tri post helix (Tolypothrix), Torikodesumiumu (Trichodesmium), Chikonema (Tychonema), and Kisenokokkasu (Xenococcus) species of one or more cyanobacteria and the like.

  After contact hydrothermal treatment, some of the products from the catalytic hydrothermal treatment can be combined with biocomponents and / or mineral (or mineral) based raw materials. The combined feedstock (or feedstock or feedstock) can include various amounts of feedstream based on the biocomponent source. When desired, the ingredients are at least about 0.1% by weight, such as at least about 0.5% by weight, at least about 1% by weight, at least about 3% by weight, at least about 10% by weight, at least about 15% by weight, at least about Ingredients based on 25% by weight, at least about 50% by weight, or at least about 75% by weight biocomponent source can be included. In such embodiments, the feedstock can additionally or alternatively include about 100 wt% or less, such as about 90 wt% or less, about 75 wt% or less, or about 50 wt% or less biocomponent. In other embodiments, the amount of the biocomponent feed (eg, for co-processing with a mineral oil (or mineral oil) portion of the feed) is, for example, at least about 0.5% by weight, eg, at least about 1%. %, At least about 2.5 wt.%, Or at least about 5 wt.%, At least about 10 wt.%, Or at least about 20 wt. obtain. In such embodiments, the feedstock is additionally or alternatively based on about 50% or less, such as about 25% or less, about 20% or less, about 10% or less, or about 5% or less biocomponent based. Feedstock can be included.

  In various embodiments of the present invention, combined feedstocks can include raw materials from various biomass or biocomponent sources, such as plants (higher plants), animals, fish, and / or algae. . In general, these biocomponent sources can include vegetable fat / oil, animal fat / oil, fish oil, pyrolysis oil, and algal lipid / oil, and components of such materials, some embodiments In particular, one or more types of lipid compounds can be mentioned. Lipid compounds are typically biological compounds that are insoluble in water but soluble in nonpolar (or fatty) solvents. Non-limiting examples of such solvents include alcohol, ether, chloroform, alkyl acetate, benzene, and combinations thereof.

  Major classes of lipids include fatty acids, glycerol derived lipids (such as fats, oils and phospholipids), sphingosine derived lipids (such as ceramide, cerebroside, ganglioside, and sphingomyelin), steroids and their derivatives, terpenes and their derivatives, These include, but are not necessarily limited to, fat-soluble vitamins, certain aromatic compounds, and long chain alcohols and waxes.

  In living organisms, lipids generally serve as cell membrane platforms and as fuel storage forms. Lipids can also be found conjugated to proteins or carbohydrates, such as in the form of lipoproteins and lipopolysaccharides.

  Examples of vegetable oils that can be used according to the present invention include rapeseed (canola) oil, soybean oil, coconut oil, sunflower oil, palm oil, palm kernel oil, peanut oil, linseed oil, tall oil, corn oil, castor oil , Jatropha oil, jojoba oil, olive oil, flax seed oil, camelina oil, safflower oil, babas oil, tallow oil and rice bran oil, but are not limited thereto.

Vegetable oils as referred to herein can also include processed vegetable oil materials. Non-limiting examples of processed vegetable oil materials include fatty acids and fatty acid alkyl esters. The alkyl esters, typically include _C 1 -C ₅ alkyl ester. One or more of the methyl, ethyl, and propyl esters are preferred.

  Examples of animal fats that can be used according to the present invention include, but are not limited to, beef tallow, lard, turkey fat, fish fat / oil, and chicken fat. Animal fats can be obtained from any suitable source, such as restaurants and meat production facilities.

Animal fat as referred to herein also includes processed animal fat materials. Non-limiting examples of processed animal fat materials include fatty acids and fatty acid alkyl esters. The alkyl esters, typically include _C 1 -C ₅ alkyl ester. One or more of the methyl, ethyl, and propyl esters are preferred.

Other biocomponent raw materials that can be used in the present invention include any of those mainly containing triglycerides and free fatty acids (FFA). Triglycerides and FFAs typically contain aliphatic hydrocarbon chains in their structure having 8 to 36 carbons, preferably 10 to 26 carbons, such as 14 to 22 carbons. The type of triglyceride can be measured according to their fatty acid constituents. Fatty acid components can be easily measured using gas chromatography (GC) analysis. This analysis includes the steps of extracting fat or oil, saponifying (hydrolyzing) the fat or oil, preparing an alkyl (eg methyl) ester of the saponified fat or oil, and GC analysis. And measuring the type of (methyl) ester. In one embodiment, based on the total triglycerides present in the lipid material, the majority (ie, greater than 50%) of the triglycerides present in the lipid material may consist of C ₁₀ -C ₂₆ fatty acid components. Furthermore, triglycerides are molecules having the same structure as the reaction product of glycerol and three fatty acids. Thus, although triglycerides are described herein as consisting of fatty acids, it should be understood that the fatty acid component does not necessarily contain hydrogen carboxylates. In one embodiment, based on total triglyceride content, the majority of the triglycerides present in the biocomponent feed may preferably consist of C ₁₂ -C ₁₈ fatty acid components. Other types of raw materials derived from biological raw material components can include fatty acid esters, such as fatty acid alkyl esters (eg, FAME and / or FAEE).

  Biocomponent-based diesel boiling range feed streams can have a wide range of nitrogen and / or sulfur content. For example, a biocomponent based feed stream based on a vegetable oil source can contain up to about 300 wppm nitrogen. In contrast, biomass-based feed streams containing whole or bursting algae can sometimes contain higher nitrogen content. Depending on the type of algae, the nitrogen content of the algae-based feed stream can be at least about 2 wt%, such as at least about 3 wt%, at least about 5 wt%, or at least about 10 wt%, and even more Algae with a high nitrogen content are known. The sulfur content of the biocomponent feed can also vary. In some embodiments, the sulfur content can be about 500 wppm or less, such as about 100 wppm or less, about 50 wppm or less, or about 10 wppm or less.

  Apart from nitrogen and sulfur, oxygen can be another heteroatom component in biocomponent-based feedstocks. A feed stream in the biocomponent diesel boiling range based on vegetable oils may contain no more than about 10% oxygen, such as no more than about 12% or no more than about 14% oxygen, prior to hydroprocessing (or hydroprocessing or hydrorefining). Can be included. Additionally or alternatively, such biocomponent diesel boiling range feed stream is at least about 1% by weight, such as at least about 2% by weight, at least about 3% by weight, at least about 4% by weight, at least about 5% by weight, at least about It may contain 6 wt%, or at least about 8 wt% oxygen. Additionally or alternatively, the biocomponent feed stream can include an olefin content of at least about 3 wt%, such as at least about 5 wt% or at least about 10 wt%, prior to hydroprocessing.

  Mineral (or mineral) hydrocarbon feedstocks are typically conventional (eg, non-biocomponent) hydrocarbons derived from crude oil and optionally subjected to one or more separation and / or refining processes. Means the feedstock. In a preferred embodiment, the mineral (or mineral) hydrocarbon feedstock may be a petroleum feedstock boiling at or above the diesel range. Examples of suitable feedstocks include virgin distillate, hydrotreated virgin distillate, kerosene, diesel boiling range feed (such as hydrotreated treated diesel boiling range feed), light circulating oil, Examples include, but are not limited to, atmospheric gas oils and combinations thereof.

  The mineral (or mineral) feed stream for blending with the biocomponent feed stream can have a nitrogen content of about 50 wppm to about 2000 wppm nitrogen, such as about 50 wppm to about 1500 wppm or about 75 to about 1000 wppm. In some embodiments, the mineral feed stream can have a sulfur content from about 100 wppm to about 10,000 wppm sulfur, such as from about 200 wppm to about 5,000 wppm or from about 350 wppm to about 2,500 wppm. Additionally or alternatively, the combined (biocomponent plus mineral (or mineral)) feedstock has a sulfur content of at least about 5 wppm, such as at least about 10 wppm, at least about 25 wppm, at least about 100 wppm, at least about 500 wppm, or at least about 1000 wppm. Can have. Additionally or alternatively, the combined feedstock can have a sulfur content of about 2000 wppm or less, such as about 1000 wppm or less, about 500 wppm or less, about 100 wppm or less, or about 50 wppm or less. Additionally or alternatively, the combined feedstock can have a nitrogen content of about 1000 wppm or less, such as about 500 wppm or less, about 100 wppm or less, about 50 wppm or less, about 30 wppm or less, about 20 wppm or less, or about 10 wppm or less.

  The content of sulfur, nitrogen, oxygen, and olefins in the feed produced by blending two or more feeds is typically determined using a weighted average based on the blended feed. Can do. For example, a mineral (or mineral) raw material and a biocomponent raw material can be blended in a ratio of 80 wt% mineral raw material and 20 wt% biocomponent raw material. If the mineral feed has a sulfur content of about 1000 wppm and the biocomponent feed has a sulfur content of about 10 wppm, the resulting blend feed could be expected to have a sulfur content of about 802 wppm. .

  A diesel boiling range feed stream suitable for use in the present invention tends to boil within the range of about 215 ° F. (about 102 ° C.) to about 800 ° F. (about 427 ° C.). Preferably, the diesel boiling range feed stream is at least about 215 ° F (about 102 ° C), such as at least about 250 ° F (about 121 ° C), at least about 275 ° F (about 135 ° C), at least about 300 ° F. (About 149 ° C), at least about 325 ° F (about 163 ° C), at least about 350 ° F (about 177 ° C), at least about 400 ° F (about 204 ° C), or at least about 451 ° F (about 233 ° C). With an initial score of Preferably, the diesel boiling range feed stream has an end point of about 800 ° F (about 427 ° C) or less, or about 775 ° F (about 413 ° C) or less, or about 750 ° F (about 399 ° C) or less. In some embodiments, the diesel boiling range feed stream may have a boiling range of about 451 ° F. (about 233 ° C.) to about 800 ° C. (about 427 ° C.). Additionally or alternatively, the feedstock can be characterized by the boiling point required to boil a specified percentage of the feedstock. For example, the temperature required to boil at least 5% by weight of the raw material is referred to as the “T5” boiling point. In one embodiment, the mineral oil (or mineral oil) feedstock is at least about 230 ° F. (about 110 ° C.), such as at least about 250 ° F. (about 121 ° C.) or at least about 275 ° F. (about 135 ° C.). It can have a T5 boiling point. Additionally or alternatively, the mineral hydrocarbon feedstock has a T95 boiling point of about 775 ° F (about 418 ° C) or less, such as about 750 ° F (about 399 ° C) or less, or about 725 ° F (about 385 ° C) or less. be able to. In another embodiment, the diesel boiling range feed stream is also a kerosene range compound to provide a feed stream in the boiling range of about 250 ° F. (about 121 ° C.) to about 800 ° F. (about 427 ° C.). Can be included.

Hydrothermal Treatment Conditions In various embodiments, the contact hydrothermal treatment can be performed in a batch, semi-batch, and / or continuous processing environment. Regardless of whether the reaction is carried out in a batch, semi-batch, or continuous reaction system, the area of any system where biomass is treated under hydrothermal treatment conditions can be referred to as a reaction zone. A reaction zone corresponds to a reactor for batch or semi-batch environments and / or a reactor, conduit, or other location for hydrothermal treatment in a continuous reaction system.

  In embodiments that include a batch reactor, the reactor can be any type of batch reactor suitable for handling process conditions. Due to the potential presence of water in supercritical conditions, stainless steel may be a suitable non-reactive material for the reactor wall. Other materials and / or coatings for the reactor surface that are compatible with the reaction conditions described herein can be used. Examples of suitable reactors can include, but are not limited to, autoclaves, stirred tanks, plow mixers, and the like, and combinations thereof. Alternatively, a bubble column could be used. One possible advantage for batch or semi-batch processing can occur for algal feedstocks that have relatively poor flow characteristics. For example, at an algal concentration of about 20% water by weight (ie, about 4 parts by weight water to 1 part algae), the resulting mixture can have a paste consistency. Such pastes can be difficult to move using, for example, a pump in a continuous flow reactor.

  In one embodiment, a batch reactor can be used for catalytic hydrothermal treatment of algae raw materials. A portion of the algae feed mixed with water can be introduced into the reactor, which can then be purged (if necessary), for example, to remove any oxygen-containing gas. Additionally or alternatively, a catalyst can also be introduced into the reactor. The catalyst can be included as part of a mixture of algae and water, or the catalyst can be introduced into the reactor as part of a separate input. Additionally or alternatively, partial pressures of inert gas and / or reducing gas can then be introduced into the reactor. An example of a suitable reducing gas may include hydrogen, while a suitable inert gas may include nitrogen. Additional or alternative examples of suitable reducing gases include any gas that does not add molecular oxygen to the reaction atmosphere, whether before the start of the reaction or from dissociation that forms oxygen during hydrothermal treatment. Can do. The partial pressure of the additional gas introduced into the reactor, when present, is at least about 1 bar (about 0.1 MPa), such as at least about 25 bar (about 2.5 MPa), at least about 40 bar (about 4.0 MPa). ), Or at least about 50 bar (about 5.0 MPa). Additionally or alternatively, the partial pressure of the gas introduced into the reactor, when present, is about 100 bar (about 10 MPa) or less, such as about 75 bar (about 7.5 MPa) or less or about 50 bar (about 5.0 MPa). It can be: Note that the introduction of the reducing gas corresponds to at least partially dissolving the reducing gas in water (eg, saturating the water) for hydrothermal treatment.

  After introducing algae, water, catalyst, and any additional reducing and / or inert gases, the batch reactor can be sealed. The temperature of the reactor is then at least about 50 ° C, such as at least about 80 ° C, at least about 100 ° C, at least about 150 ° C, at least about 200 ° C, at least about 250 ° C, at least about 275 ° C, or at least about 300 ° C. Can be raised. Additionally or alternatively, the temperature of the reactor can be raised to about 500 ° C or lower, such as about 400 ° C or lower, about 380 ° C or lower, about 350 ° C or lower, about 300 ° C or lower, or about 275 ° C or lower. Additionally or alternatively, the pressure in the reactor is at least about 1 barg (about 0.1 MPag), such as at least about 4.5 barg (about 450 kPag), at least about 25 barg (about 2.5 MPag), at least about 40 barg (about 4 barg). 0.0 MPag), at least about 50 barg (about 5.0 MPag), or at least about 100 barg (about 10 MPag). Additionally or alternatively, the partial pressure of the gas introduced into the reactor, when present, is about 300 barg (about 30 MPag) or less, such as about 250 barg (about 25 MPag) or less, about 225 barg (about 22.5 MPag) or less, or about 200 barg. (About 20 MPag) or less.

  In some embodiments, the combination of pressure and temperature in the reactor is selected such that the water in the reactor is substantially free from phase change (eg, completely free of phase change). Can do. In the phase diagram for water, the critical point is at a temperature of about 374 ° C. and a pressure of about 22 MPa. With combinations of temperature and pressure beyond this point in the phase diagram, water does not experience a phase transition between the liquid phase and the gas phase. Instead, above the critical point, water behaves as a single fluid phase. Thus, in some embodiments, the combination of pressure and temperature can be selected such that the liquid water in the reactor remains in a stable phase until a state above the critical point is achieved. . One way to meet this condition may be to select a reaction temperature and pressure that is below the critical point and thus does not lead to a phase transition. In some embodiments, an additional partial pressure of gas can be introduced into the reactor (in which case some minimum amount of water becomes steam, but this situation is not a “substantial” phase change). Note that this is contemplated by the present invention). If the partial pressure of the additional gas is greater than about 22 MPa, this pressure is already above the critical point for water and a phase transition is virtually impossible at all. For example, in a closed reactor that can have another gas partial pressure, as long as the volume of liquid water is sufficient compared to the volume of the reactor, a substantial phase transition of water is unlikely to occur. Also note that.

  Additionally or alternatively, the pressure in the reactor can be set by selecting the temperature for the water. In some embodiments, the reactor, if present, can be sealed or closed after introduction of water and any additional gases. The partial pressure of water vapor should be developed in the reactor to correspond to the temperature in the reactor. As the reactor temperature increases, a corresponding higher partial pressure of water should occur in the reactor. Hydrothermal treatment combines the partial pressure of water at the reaction temperature with the partial pressure of any additional inert gas and / or reducing gas, and the partial pressure of any gas generated or released during processing. Can be performed at the pressures represented. Examples of water pressure at various temperatures include about 0.01 MPa at about 50 ° C .; about 0.05 MPa at about 80 ° C .; about 0.1 MPa at about 100 ° C .; about 0.5 MPa at about 150 ° C .; About 1.6 MPa at about 250 ° C; about 4.0 MPa at about 250 ° C; about 5.9 MPa at about 275 ° C; about 8.6 MPa at about 300 ° C; about 16.5 MPa at about 350 ° C; and about 22 at about 374 ° C. .1 MPa can be mentioned. About 22.1 MPa and about 374 ° C. correspond to critical points in the phase diagram for water, so it makes no sense to refer to the partial pressure of “water vapor” in the reactor at temperatures above that point.

  In some embodiments, the hydrothermal treatment can be performed in a continuous flow reactor. An example of a continuous flow reactor can be a pipe or other conduit that can be heated to raise the temperature of the feedstock in the conduit to the desired hydrothermal treatment temperature. For example, a conduit passing through the furnace and / or a conduit surrounded by steam could be used. The conduit can have any convenient shape for passing through a heating zone (or heating zone). For example, a conduit having a helical shape can be used to increase the size of the conduit portion within the heating zone.

  It has been pointed out that the amount of water required to perform hydrothermal treatment may not be sufficient to provide the type of flow characteristics desired for a continuous flow environment. One option for improving the fluid flow characteristics of algae in a continuous flow processing environment could be to increase the moisture content of the algae raw material. However, an increase in moisture content can also result in a corresponding decrease in yield per volume of reaction system due to a decrease in the amount of algae in the feed.

  FIG. 1 schematically illustrates an example of a reactor suitable for use in certain embodiments of the present invention. In FIG. 1, hydrothermal reactor 100 can represent any type of reactor suitable for performing a catalytic hydrothermal process for the treatment of algae (or other biomass) feedstock. The input flow to the reactor 100 can include a gas input 102, such as an inert gas input, a hydrogen gas input, another type of reducing gas input, or a combination thereof. Another input flow may be algae or biomass input 104. If the algae input 104 has insufficient flow characteristics, such as due to a sufficiently low moisture content, the algae input 104 may alternatively be non-extruded, such as extruded, injected, or dumped into the reactor 100. It may represent a flow input. Optionally, supplemental input flow 105 can be provided for a variety of reasons. One option for the auxiliary input flow 105 may be to include additional water so that hydrothermal treatment conditions can be maintained. Additional or alternative components for the auxiliary input flow 105 may be “inert” hydrocarbon streams and / or product recycle streams (which may undergo minimal reaction under hydrothermal conditions). Such hydrocarbon stream and / or recycle stream could be used as a carrier for the catalyst or catalyst precursor. As an alternative, the algae input 104 and supplemental input 105 can be combined into a single stream prior to entering the reactor 100. Hydrothermal treatment can produce an output flow 107 that can be, for example, a mixture of various phases. The phases that can constitute the output flow 107 can include a gas phase, a hydrocarbon-based phase, an aqueous phase, and one or more solid phases. These phases may optionally be mixed together, such as mixing the solids and aqueous phases.

Catalyst for catalytic hydrothermal treatment Another option during treatment may be the use of a hydrothermal catalyst. The hydrothermal treatment catalyst may be in a form that is soluble in the hydrothermal reaction environment (or in at least one feed introduced therein), or the catalyst may be in the form of catalyst particles in the hydrothermal reaction environment. The catalyst particles in the reaction environment can have any suitable particle size and / or particle size distribution. The catalyst particles can optionally be a supported catalyst with the catalyst material supported on a substrate.

In embodiments that include a catalyst that is soluble in the hydrothermal reaction environment, the catalyst can be introduced into the reaction as either a catalyst or a catalyst precursor. The soluble catalyst can be soluble in water introduced into the hydrothermal reaction environment or in another solvent. Examples of solvents can include, but are not limited to, alcohols, acids, hydrocarbons, or other oils. Additionally or alternatively, the solvent may correspond to the product produced by the hydrothermal process. Examples of suitable catalysts or catalyst precursors can include, but are not limited to, transition metal salts such as metal acetates, metal carbonates, metal acetylacetonates, or combinations thereof. Examples of suitable metals for such metal salts can include, but are not limited to, Cr, V, Mo, Ni, Cu, Fe, Co, Mn, and combinations thereof. Additionally or alternatively, suitable metals can include a Group VIB metal or a Group VIII metal, or a combination of one or more Group VIB metals and one or more Group VIII non-noble metals. Additionally or alternatively, the catalyst precursor can be activated to form a metal sulfide by introducing a sulfur-containing stream, such as a H ₂ S stream, into the reaction environment.

  The amount of metal of the soluble catalyst or catalyst precursor in the reactor (reaction zone) relative to the amount of algae is at least about 0.01 wt% (100 wppm), such as at least about 0.05 wt%, at least about 0.1 % By weight, at least about 0.25% by weight, or at least about 0.5% by weight. Additionally or alternatively, the amount of catalyst in the reactor (reaction zone) is about 5.0 wt% or less, such as about 3.0 wt% or less, about 2.0 wt% or less, about 1. It can be 0 wt% or less, about 0.5 wt% or less, or about 0.25 wt% or less.

  Apart from soluble catalyst options, supported catalysts comprising noble metals (eg, Pt, Pd, Rh, Ru, Ir, or combinations thereof) can be used. Additionally or alternatively, the support for the catalyst can be a hydrothermally stable support. Examples of suitable supports include refractory oxides such as titania and / or zirconia; silica; activated carbon; one or more metals selected from titanium, zirconium, vanadium, molybdenum, manganese, and cerium deposited thereon Can include carbon oxides; magnesium oxide; hydrotalcite; various other types of clays; and combinations thereof, such as a mixture of two or more of titania, zirconia, and silica. It is not limited. Additionally or alternatively, the support material can be substantially free of alumina. As used herein, “substantially free” of alumina is less than 1 wt.% Alumina, preferably less than 0.1 wt.% Alumina, such as less than 0.01 wt.% Alumina, completely free of alumina. It should be understood to mean that the added alumina or completely free of alumina.

  Yet another catalyst option may be to use basic or mixed metal oxides with or without noble metals. Examples of such catalysts without precious metals can include, but are not limited to, magnesium oxide, hydrotalcite, potassium supported on titania and / or zirconia, and combinations thereof.

  Yet another catalyst option may be to use a hydrotreating (or hydrotreating or hydrorefining) type metal supported on a suitable support. Examples of hydroprocessing type metals can include, but are not limited to, combinations of Group VIII metals (such as Co and / or Ni) and Group VIB metals (such as Mo and / or W). A combination of more than two Group VIII metals and / or Group VI metals can be used or alternatively (eg, NiMoW, CoNiMo, CoMoW, etc.). Suitable supports include those specified above in this specification.

  Yet another catalyst option may be to select a catalyst comprising a biocompatible material. For example, biocompatible materials are materials that can serve as nutrients (or nutrients) for the growth (or growth) of biomass, such as algae, and / or materials used for hydrothermal treatment It can be a material that does not adversely affect the biomass growth environment at a concentration of. The biocompatible catalyst can optionally include a biocompatible carrier. Examples of suitable metals in the biocompatible catalyst can include K, Na, Mg, Ca, Fe, Zn, Mn, Mo, Cu, and combinations thereof. The biocompatible catalyst can be in the form of a hydroxide, oxide, carbonate, or organometallic derivative such as acetate or acetylacetonate (acac). Additionally or alternatively, the catalyst can be impregnated on a support such as activated carbon. The biomass being treated, such as algae, can alternatively serve as a support for the catalyst. In some embodiments, these biocompatible catalyst materials can be recycled either as a nutrient feedstock for biomass growth or as an input to a hydrothermal treatment reaction.

  With respect to the amount of algae, the amount of catalyst in the reactor (reaction zone) is at least about 0.05 wt%, such as at least about 0.1 wt%, at least about 1 wt%, at least about 2.5 wt%, Or at least about 5% by weight. Additionally or alternatively, the amount of catalyst in the reactor (reaction zone) can be about 20 wt% or less, such as about 15 wt% or less, or about 10 wt% or less based on the amount of algae.

  The amount of metal supported on the catalyst can vary. When present, the amount of noble metal supported on the catalyst, based on the weight of the catalyst, is at least about 0.1 wt%, such as at least about 0.5 wt%, at least about 0.00, based on the total catalyst weight. It may be 6% by weight, at least about 0.75% by weight, or at least about 1.0% by weight. Additionally or alternatively, the amount of noble metal supported on the catalyst, when present, is about 1.5% or less, such as about 1.0% or less, about 0.75% or less, based on the total catalyst weight. Or about 0.6 wt% or less. More generally, the amount of metal on the catalyst support is at least about 0.1%, such as at least about 0.25% by weight, at least about 0.5%, individually or in a mixture, based on the total catalyst weight. % By weight, at least about 0.6% by weight, at least about 0.75% by weight, at least about 1% by weight, at least about 2.5% by weight, or at least about 5% by weight. Additionally or alternatively, the amount of metal on the catalyst support, individually or in a mixture, is about 35% or less, such as about 20% or less, about 15% or less, about 10% or less, based on the total catalyst weight. Or about 5% or less by weight.

  The use of a catalyst can pose additional problems for hydrothermal treatment. For a catalyst or catalyst precursor that is initially soluble in the reaction environment, one problem may be the separation of the catalyst from the reaction product. One separation method may be filtration. If the catalyst is not soluble in the reaction product, the resulting catalyst particles can be filtered out of the product in which the catalyst particles are mixed. One reason that the catalyst may be insoluble in the reaction product is when the catalyst has been converted to another form, such as conversion of the catalyst precursor to a metal sulfide.

  Supported (or particulate) catalysts may also present additional considerations. Additionally or alternatively, the particle size for the catalyst particles can be varied, eg, selected, to facilitate separation of the catalyst particles from other solids. In such embodiments, the catalyst particles can have an average particle size of at least about 1000 μm, such as at least about 1500 μm or at least about 2000 μm. In order to achieve the desired catalyst particle size, the catalyst, if present, can optionally be formulated to include a hydrothermally stable binder material in addition to the support material and any active metals. A suitable hydrothermally stable binder material can be similar to the material used as the support and / or one selected from silicon, titanium, zirconium, vanadium, molybdenum, manganese, and cerium Although the oxide of the above metals can be included, it is not necessarily limited to them. For supported catalysts blended with a binder, the support material can serve as a binder, or a different material can be used as the binder.

  The supported catalyst can be contacted with the feedstock under hydrothermal treatment conditions using various reactor types. Batch or semi-batch reactors as described above can be used with the particulate catalyst. For example, the catalyst can be added to such a reactor when algae, water, and other optional gases are added to the reactor. A continuous flow conduit may additionally or alternatively be used. In this type of embodiment, the flow through the conduit may resemble a slurry of catalyst particles suspended in a flow of algae and water.

  In addition to reactors suitable for non-contact processing, other types of continuous flow reactors, such as fixed bed reactors, moving beds, suspension bubble column reactors (or ebullating bed reactors), potentially algae It can be used for hydrothermal treatment of raw materials. When a fixed bed reactor is used, one concern can be contamination of the catalyst bed, for example, due to solids present in the biomass or algal feed. Contamination of the catalyst bed can result in a higher pressure drop than expected across the catalyst bed due to the restriction of feed flow through the bed. Fixed bed reactors are often able to process feedstock with a particle size of about 150 μm or less without significant contamination problems. Nevertheless, any contamination of the catalyst bed can be somewhat mitigated, for example, by having a bypass tube to control the pressure drop across the catalyst bed. Unfortunately, individual algal cells have a small diameter compared to 150 μm, but hydrothermally processed algae can have an increased tendency to aggregate. As a result, more than 5% of the algae-based solids resulting from the hydrothermal treatment of the algae raw material can be in the form of aggregated particles with a particle size greater than 150 μm. Nevertheless, in some embodiments, the fixed bed reactor is when the agglomeration behavior of product algae solids can be mitigated, for example, by using sufficient space velocity and / or by other means. In particular, it may be used.

  As an alternative to a fixed bed reactor, a suspended bubble column reactor can be used for hydrothermal treatment. In a conventional suspended bubble column reactor, both feedstock (water and algae) and process gas (hydrogen-containing reducing gas) can be introduced into the reactor from the bottom of the reactor. In such a reactor, recycled feed containing a portion of the reactor effluent can also be introduced into the bottom of the reactor. These feed flows can move up into the reactor and pass through a catalyst support grid designed to prevent catalyst from entering this area at the bottom of the reactor where the feed pump is located. The catalyst in such a suspended bubble column reactor is typically placed above the catalyst support grid.

When the feed (and optionally additional gas) flow reaches the catalyst bed, the bed generally becomes fluidized, resulting in expansion of the bed as well as mixing within the bed. The feedstock (and hydrogen) can react in the bed to form products, including liquid products, solid products, and gaseous products. The flow in a conventional suspension bubble column reactor can continue upward until the effluent is withdrawn at the top. This effluent is composed of the desired product, unreacted hydrogen (when present), and by-product gases, including contaminant gases such as H ₂ S or NH ₃ that may have formed during the reaction. It can be a combination. In a preferred embodiment, a portion of the liquid effluent can be recycled, for example, to the bottom of the reactor. If necessary, the gas can be separated from the liquid portion of the effluent.

Phosphorus content in the solid fraction In addition to or instead of hydrocarbon product recovery, recovery of other algal solids (or other biomass solids) may be beneficial. For example, phosphorus can be recovered from residual algae solids after hydrothermal treatment. One potential use for recovered phosphorus may be as a nutrient for the growth (or growth) of additional algae or other biomass.

  Improving the recovery of phosphorus from the hydrothermal treatment of biomass can include balancing several factors. One benefit of various embodiments may be that the phosphorus forms a solid product that can be filtered, for example, from a liquid product stream. Any phosphorus remaining as part of the liquid hydrocarbon product and / or any phosphorus that will be solubilized in the solvent could be recovered in one or more separate, additional processes. In the discussion below, the recovery of phosphorus from the hydrothermal product can be evaluated based on the amount of phosphorus recovered as a solid.

Since phosphorus recovery can be assessed based on the amount of phosphorus in the solid product, the initial goal may be to develop process conditions that result in a large percentage of phosphorus in the solid product. One conventional method of treating biomass feedstock, such as algae feedstock, is to extract the desired hydrocarbon product from the feedstock using an extraction solvent (eg, a mixture of CHCl ₃ and CH ₃ OH). possible. The extraction solvent can advantageously obtain a yield of phosphorus in the solid product of more than 90% by weight relative to the amount of phosphorus in the feedstock. For an efficient phosphorus recovery process, it is desirable to obtain a phosphorus yield in the solid product of at least 80 wt%, for example at least 85 wt% or at least 90 wt%, relative to the raw phosphorus content. possible.

  One option for improving the yield of phosphorus in the solid product may be to increase the amount of multivalent cation in the hydrothermal reaction. Many biomass feedstocks can contain at least some multivalent cations such as Ca, Mg, and / or Fe. These multivalent cations can form phosphates or other phosphorus solids as part of the solid product. For some feedstocks, increasing the amount of available multivalent cations, such as by adding additional cations selected from Ca, Mg, Fe, Al, or combinations thereof, in the solid product May increase the amount of phosphorus. In some such embodiments, sufficient multivalent cation can be added to provide at least about a 1: 1 molar ratio of multivalent cation to phosphorus atoms. This may correspond to adding at least about 0.1 wt%, such as at least about 0.2 wt% or at least about 0.3 wt% polyvalent metal. Additionally or alternatively, the amount of added polyvalent metal can be about 1.0 wt% or less, such as about 0.8 wt% or less, about 0.6 wt% or less, or about 0.5 wt% or less. . It should be noted that the amount of polyvalent metal can be reduced for raw materials that already contain some polyvalent metal.

  Another consideration in selecting conditions for hydrothermal treatment may be the relative amount of phosphorus in the solid product. As pointed out above, solvent extraction can produce a solid product with more than 90% by weight of the initial phosphorus in the feedstock. Unfortunately, such conventional solvent treatment can also result in relatively large amounts of carbonaceous solids, for example, where phosphorus can be present in the product in amounts as low as 5% by weight or less. This can pose many problems. First, additional processing may be required to extract phosphorus from a much larger percentage of carbon solids and / or other solids. Another problem may be that the relatively high carbon content in the solid product can increase the difficulty of using / selling this solid for high economic value purposes. In other words, it may mean that a large proportion of carbon in the solid product means that a noticeable amount of carbon can be lost rather than converted into the desired product. .

  The amount of phosphorus recovered in the solid product relative to carbon can depend to some extent on the reaction conditions. Without being bound by any particular theory, it is believed that relatively low severity reaction conditions can lead to incomplete reaction of the biomass feedstock. This can result in algae (or other biomass) solids that are unreacted and / or only partially reacted. Algae are initially solid, so unreacted and / or partially reacted algae can still be solid after incomplete reaction. Unreacted and / or partially reacted algae can thus increase the carbon content of the solid product, which can therefore reduce the phosphorus to carbon ratio. It should be noted that incomplete reactions may additionally or alternatively lead to a decrease in the amount of phosphorus in the solids relative to the initial amount of phosphorus.

  Similarly, without being bound by theory, it is believed that reaction conditions that are too harsh can lead to an increase in carbon in the solid product. Hydrothermal treatment of biomass feedstocks can lead to increased production of some heavier molecules, such as aromatic compounds. These heavier molecular parts may represent insoluble compounds that tend to form solids. These additional solids may therefore be involved in reducing the phosphorus to carbon ratio in the solid product.

  In some embodiments, the hydrothermal treatment temperature can be selected to improve the phosphorus to carbon ratio in the solid product. For example, the reaction temperature can range from about 275 ° C. to about 325 ° C. in one embodiment. Additionally or alternatively, in the catalytic hydrothermal treatment embodiment, the presence of the catalyst can lower the treatment temperature, which leads to an increase in the phosphorus to carbon ratio in the solid product. In such embodiments, the reaction temperature can range from about 250 ° C to about 300 ° C.

  Additionally or alternatively, the improvement of the phosphorus to carbon ratio in the solid product for hydrothermal treatment, either in the presence or absence of a catalyst, can be based on a combination of treatment temperature and reaction time. For example, for a processing time of about 60 minutes to about 105 minutes, the reaction temperature can be about 250 ° C to about 300 ° C. For a processing time of about 45 minutes to about 90 minutes, the reaction temperature can be about 275 ° C to about 325 ° C. For a processing time of about 30 minutes to about 60 minutes, the reaction temperature can be about 285 ° C to about 335 ° C. For a processing time of about 24 minutes to about 48 minutes, the reaction temperature can be about 300 ° C to about 350 ° C. For a processing time of about 15 minutes to about 30 minutes, the reaction temperature can be about 325 ° C to about 375 ° C. For a processing time of about 6 minutes to about 24 minutes, the reaction temperature can be about 350 ° C to about 400 ° C.

  Additionally or alternatively, the improvement of the phosphorus to carbon ratio in the solid product for catalytic hydrothermal treatment can be based on a combination of treatment temperature and reaction time. For example, for a processing time of about 60 minutes to about 105 minutes, the reaction temperature can be about 225 ° C. to about 275 ° C .; for a processing time of about 45 minutes to about 90 minutes, the reaction temperature is about For a processing time of about 30 minutes to about 60 minutes, the reaction temperature can be about 275 ° C. to about 325 ° C .; for a processing time of about 24 minutes to about 48 minutes In contrast, the reaction temperature can be about 285 ° C to about 335 ° C; for a processing time of about 15 minutes to about 30 minutes, the reaction temperature can be about 300 ° C to about 350 ° C; and about 6 For processing times of from about 24 minutes to about 24 minutes, the reaction temperature can be from about 325 ° C to about 375 ° C. Note that in a continuous reaction environment, the reaction time can be more accurately described in terms of residence time or space velocity.

Product Separation from Catalytic Hydrothermal Treatment Hydrothermal treatment can yield multiphase products. The multiphase product can include a gas phase, a hydrocarbon or oil phase, and an aqueous phase that can include solids. The gas phase, oil phase, aqueous phase, and solid phase can be separated from each other by any convenient method, such as using a three-phase separator. Oil phase characterization is further described below. In some embodiments, the solid phase can be with the initial aqueous phase. For example, the solid phase can be suspended in the aqueous phase, or can be a precipitate slurried in the aqueous phase and / or settled from the aqueous phase. The solid phase is also inter alia; phosphorus and other potential nutrients for algae and / or other microorganisms; unreacted and / or partially reacted biomass; and optionally, the process is a catalytic hydrothermal process Can be beneficial, containing one or more of the catalyst particles. In some embodiments, the catalyst particles can be separated from other solids to allow their recycling as well as, if present, nutrient recycling.

  FIG. 2 shows a schematic example of a processing flow for an embodiment of the present invention that includes algae as a form of biomass for processing. In FIG. 2, an integrated scheme is shown in which the product from (optionally contacting) hydrothermal treatment is recycled for further use. In FIG. 2, the biomass input for hydrothermal treatment can be from an algal source. The algae can be produced by an algae growth process 210, which can include any convenient and / or known process. The algae can be harvested (or recovered) 220 for conversion (or conversion) to a hydrocarbon product. As part of the algae harvest 220, an amount of water can optionally be removed from the algae. For example, water can be completely removed from algae as part of the production of lyophilized algae. Alternatively, water can be removed using only a physical process, such as by a centrifuge, which is advantageously about 10: 1 or less, such as about 7.5: 1 or less, or about Algal raw materials with a water to algal weight ratio of 5: 1 or less can be provided. Additionally or alternatively, the water to algae weight ratio can be at least about 2: 1, such as at least about 2.5: 1, or at least about 3: 1. One advantage of performing only partial separation of algae and water may be that less energy is required to perform only partial separation compared to complete separation.

After harvesting, the harvested algae can be used as a raw material for the hydrothermal treatment 230. The algal raw material can optionally be combined with a catalyst, a partial pressure of a gas such as hydrogen, and optionally with water if, for example, sufficient water is not included in the algal raw material. Hydrothermal treatment 230 can produce a variety of products. The initial separation of these products can be performed with a three-phase separator 240. The three-phase separator 240 can be used to produce a gas phase product 242, a hydrocarbon or oil product 248, and a product 246 that includes water and various solids. Vapor phase product 242 is hydrogen, inert gas may be present in the hydrothermal treatment 230, the product gas from the hydrothermal treatment _{230 (CO 2, CO, H} 2 S, such as NH _3, and combinations thereof As well as low boiling hydrocarbons produced during the catalytic hydrothermal treatment 230. Low boiling hydrocarbons can include hydrocarbons that are gases at room temperature (such as methane, ethane, or combinations thereof) and / or hydrocarbons that are gases at the temperature of three-phase separation. If the three-phase separation is performed at an elevated temperature, this could include higher boiling aliphatic hydrocarbons and / or other species (such as methanol). Note that some of the above products, such as product gas from hydrothermal treatment, may be at least partially solubilized in the aqueous phase.

  In the product from hydrothermal treatment 230, the desired hydrocarbon or oil (or oil) product can form a phase separate from the aqueous phase containing various solids. These separate phases can be separated in a three-phase separation 240. The resulting hydrocarbon product 248 can represent the desired oil product from a catalytic hydrothermal treatment. The hydrocarbon product 248 is optionally distilled 260 and / or for use in isolating the desired boiling range products 262 and 263 and / or for use with the hydrocarbon product 248 or distillation cut 262 or 263. Various additional treatments may be received, which may include hydrotreating (or hydrotreating or hydrorefining) to enhance the quality of the. Additionally or alternatively, at least a portion of the hydrocarbon product 248 and / or distillation cuts 262 and / or 263 may improve input feed flow characteristics, eg, in combination with an algae / water input feed In addition, the hydrothermal treatment 230 may optionally be recycled.

In some embodiments, the water and solids 246 from the three-phase separation 240 are solids derived from algae, phosphorus and / or various metals, unreacted and / or partially reacted biomass, and optionally Several types of solids can be included, including but not limited to solids including catalyst particles, such as spent catalyst particles. Water and solids 246 can be further processed with solids separation 250 to separate the solids for further use. Solids separation 250 can produce aqueous stream 257, optional catalyst particles 253, and algae-derived solids 259. Note that separation of the optional catalyst particles from the algae-derived solids may occur prior to the separation of the aqueous phase from the solids. In a preferred embodiment, the optional catalyst particles 253 can be returned to the catalytic hydrothermal treatment for further use. Additionally or alternatively, the algae-derived solids 259 can be returned to the algae growth process 210, for example, as a raw material for growing a new batch of algae raw material. In addition or alternatively, at least a portion of the aqueous stream 257 and / or water and water from the solids 246, for example, to provide additional nutrients such as nitrogenous species (such as NH ₃ ) It can be recycled to the growth process 210.

  Although the scheme in FIG. 2 implies a series of processes arranged together, algae growth 210 and harvest 220 could be performed away from the contact hydrothermal treatment 230. In such an embodiment, some of the arrows in FIG. 2 indicate transfer processes, such as transfer of harvested algae to a location for catalytic hydrothermal treatment and transfer of algae-derived solids to an algae growth site. Can be expressed.

Treatment of Product Solids for Recycling of Nutrients As noted above, some of the product solids (or solids) are for use as nutrients for further algae or other biomass growth. Can be recycled. An example of this type of recycling may be the recycling of phosphorus compounds. In order to recycle phosphorus, it can be converted from a solid form to a precursor form that can be easily processed into suitable nutrients. An example of this type of conversion may be the conversion of phosphorus in the product solids to a more readily distributable form such as phosphoric acid. Phosphoric acid can then be used either as a nutrient or as a precursor or a reagent for making suitable nutrients.

  Phosphorus can be included in the product solids in various forms, such as phosphate and / or phosphite, and can be coordinated with Ca, Mg, or other multivalent cations. The solids can also contain a carbon compound. In order to separate the phosphorus from the carbon, the phosphorus in the solids can be converted to phosphoric acid in one embodiment. Conversion of phosphorus to phosphoric acid is a known reaction, and can be performed by treating a phosphorus-containing solid with sulfuric acid. Sulfuric acid can react with phosphorus to form phosphoric acid. Sulfate ions from sulfuric acid bind to Ca or Mg cations and precipitate. In such situations, carbon may remain as an additional solid product. Sulfate solids and carbon can be separated from phosphoric acid by physical and / or known / conventional means, for example, using filtration or sedimentation basins.

Evaluation of Products from Hydrothermal Treatment Hydrothermal treatment can be used to extract various hydrocarbon fractions (or fractions) from algae (or other biomass) feedstock. An example of a hydrocarbon fraction that can be extracted from an algal feedstock can include a distillate fraction and / or can be a distillate fraction. In the discussion below, the distillate fraction is a fraction having a boiling range of about 193 ° C. to about 360 ° C., or alternatively a fraction having at least 90% by weight having a boiling range of about 193 ° C. to about 360 ° C. (Eg, a fraction in which T5 can be about 193 ° C., T95 can be about 360 ° C., or T2 can be about 193 ° C., T98 can be about 360 ° C., etc.).

  One method for evaluating the product of the hydrothermal process, whether contacted or non-contacted, may be to consider the hydrocarbon yield from this process. The total yield can be defined for the hydrothermal process based on the weight of hydrocarbon product obtained relative to the initial weight of algae or other biomass. Distillate yield can also be defined for the hydrothermal process. One yield characterization can be the total distillate boiling range yield for the process relative to the starting weight of the algae or biomass. Another characterization can be the percentage of distillate produced relative to the total hydrocarbon yield.

Additional or alternative methods for evaluating the product of the hydrothermal process can be based on the level of various impurities in the product. In a non-contact hydrothermal process (or in a catalytic hydrothermal process that is analyzed on a catalyst-free basis), the hydrocarbon products are such as nitrogen, oxygen, carbon-carbon double bonds, and aromatic groups. There may be a tendency to incorporate impurities. Thus, the percentage of heteroatoms (nitrogen and / or oxygen) in the total hydrocarbon product and / or distillate product may be of interest. The percentage of carbon-carbon double bonds and aromatic groups can be measured using techniques such as ¹³ C NMR, and / or using other metrics such as the ratio of hydrogen to carbon in the product. Can do.

Additional Embodiments Additionally or alternatively, the present invention can include one or more of the following embodiments.

Embodiment 1
Introducing a biomass feedstock having a water: biomass ratio of at least 1: 1 into the reaction zone, the biomass feedstock having a phosphorus content (or including phosphorus);
Hydrothermally treating the biomass feedstock under hydrothermal treatment conditions effective to produce a multiphase product, wherein the multiphase product comprises at least about 80% of the phosphorus content of the biomass feedstock Including a solid portion;
Separating the multi-phase product to produce at least a gas phase portion, a liquid hydrocarbon product, and the solid portion.

Embodiment 2
Adding a polyvalent metal to a biomass raw material having a phosphorus content;
Contacting the biomass feedstock with water in the presence of the polyvalent metal under hydrothermal conditions effective to produce a multiphase product, wherein the multiphase product is phosphorous of the biomass feedstock. Comprising a solid portion comprising at least about 80% of the content;
Separating the multi-phase product to produce at least a gas phase portion, a liquid hydrocarbon product, and the solid portion.

Embodiment 3
The method of embodiment 2, wherein the multivalent metal comprises Ca, Mg, Fe, or a combination thereof, eg, Ca and / or Mg.

Embodiment 4
The method of Embodiment 2 or Embodiment 3, wherein the polyvalent metal is added to the biomass feedstock in a reaction zone in the step of contacting the biomass feedstock with water under effective hydrothermal conditions.

Embodiment 5
The method of any one of Embodiments 1-4 in which the said biomass raw material contains algae.

Embodiment 6
A step of contacting an algae-containing biomass material having a phosphorus content (or containing phosphorus) with water under hydrothermal treatment conditions effective to produce a multiphase product, wherein the multiphase product is the alga Including a solid portion comprising at least about 80% of the phosphorus content of the contained biomass feedstock;
Separating the multiphase product to produce at least a gas phase portion, a liquid hydrocarbon product, and the solid portion;
Recycling the phosphorus from the solid part to an algal growth environment.

Embodiment 7
Recycling phosphorus from the solid part
Extracting phosphorus from the solid portion to form a phosphorus-based nutrient or nutrient precursor, and introducing the phosphorus-based nutrient or nutrient precursor into the algae growth environment. Method.

Embodiment 8
Embodiment 8. The method of embodiment 7 wherein the phosphorus-based nutrient or nutrient precursor is phosphoric acid.

Embodiment 9
The method of any one of embodiments 1-8, wherein the weight ratio of water: algae is about 2: 1 to about 10: 1, such as about 3: 1 to about 5: 1.

Embodiment 10
Embodiments wherein the effective hydrothermal treatment conditions include a temperature of about 150 ° C to about 500 ° C, such as a temperature of about 250 ° C to about 375 ° C, and a pressure of about 25 barg (about 2.5 MPag) to about 300 barg (about 30 MPag). Any one method of 1-9.

Embodiment 11
The effective hydrothermal treatment conditions include hydrothermal treatment in the presence of a catalyst, and the following conditions:
The treatment time is about 45 minutes to about 90 minutes when the temperature is about 250 ° C. to about 300 ° C .;
The treatment time is about 30 minutes to about 60 minutes when the temperature is about 275 ° C. to about 325 ° C., or the treatment time is about 15 minutes to about 30 when the temperature is about 300 ° C. to about 350 ° C. The method of any one of embodiments 1-10, wherein one of the minutes is satisfied.

Embodiment 12
The method of any one of embodiments 1-11, wherein the step of contacting the algae-based material with water under effective hydrothermal treatment conditions does not substantially result in a phase change of water.

Embodiment 13
Any of embodiments 1-12, further comprising separating the liquid hydrocarbon product to produce a fraction (or fraction) of which at least 90% has a boiling range of about 193 ° C. to about 360 ° C. Or one way.

Embodiment 14
The solid portion has a phosphorus: carbon molar ratio of at least about 0.2, such as at least about 0.25, and the solid portion optionally includes a phosphorus content of at least about 90% of the biomass feedstock. The method of any one of Embodiments 1-13.

Phosphorus Recovery Examples A series of experiments were conducted to test phosphorus recovery from conventional solvent treatment of algae raw materials and from hydrothermal treatment of algae raw materials. A commercially available freeze-dried Nannochloropsis algal sample was used for this experiment.

For solvent treatment, the solvent was a 50:50 mixture of CHCl ₃ and CH ₃ OH on a volume basis. Some lyophilized Nannochloropsis algae were combined with 5 parts CHCl ₃ / CH ₃ OH solvent and stirred vigorously at room temperature (ie, about 20-25 ° C.) for about 24 hours. Two distinct phases are apparent, the first phase contains the solvent and the solubilized product, and the second phase contains the solid residue suspended in the solvent and / or settled at the bottom of the solvent. Contained. The solid residue was isolated and analyzed; the results of these characterizations are shown in Table 3 below.

  For hydrothermal treatment experiments, a sample of lyophilized algae was mixed with water at a ratio of about 4 parts water to 1 part algae. The mixture of algae and water was placed in an approximately 1 inch outer diameter reactor (Swagelok cap and stopper) of 316SS stainless steel. A nitrogen partial pressure of about 50 bar (about 5.0 MPa) was applied to the reactor. A separate catalyst was not added to the reactor. The reactor was placed in a preheated suspended foam sand bath. The reactor remained in the sand bath for about 60 minutes. The reactor was then removed from the sand bath and quenched to approximately room temperature. The hydrocarbon product was recovered using methylene chloride extraction and phase separation. In the experiments described below, the temperature of the sand bath (and hence the reactor) was about 200 ° C, about 300 ° C, or about 350 ° C.

Table 3 shows examples of treatment of algal samples using solvent extraction and at three hydrothermal treatment temperatures. In this table, the term “phosphorus yield” means the weight percent of phosphorus from the initial sample contained in the solid product. Phosphorus concentration means the weight percent of phosphorus in the solid product. P / C molar ratio means the molar ratio of phosphorus to carbon in the solid product. Phosphorus recovery efficiency is a measure of the relative amounts of phosphorus and carbon in the solid product. Phosphorus recovery efficiency is defined as P _{recovery efficiency} = P _yield × [P _mole / (P _mole + C _mole )].

  In Table 3, column A shows the results from analysis of product solids from solvent extraction. Columns B, C, and D show the results from analysis of the solid fraction from hydrothermal treatment at about 200 ° C., about 300 ° C., and about 350 ° C., respectively.

  As shown in Table 1, solvent extraction resulted in a relatively high phosphorus yield at 97% solid product. However, the solid product also contained large amounts of other materials, as indicated by the total weight percentage of phosphorus (1.55%). The majority of this additional material was carbon, as indicated by the phosphorus to carbon molar ratio (0.014). As a result, the phosphorus recovery efficiency, as defined above, was only 1.3%.

  For hydrothermal treatment at about 200 ° C., the phosphorus yield was lower at about 34%. Due to the low initial recovery and the relatively low concentration of phosphorus in the solids, the phosphorus recovery efficiency at about 200 ° C. was less than 1%.

  At higher processing temperatures, the phosphorus recovery efficiency was significantly higher. At both about 300 ° C. and about 350 ° C., the phosphorus yield was greater than about 90%, indicating good acquisition of initial phosphorus in the solid product. Both the about 300 ° C. and about 350 ° C. experiments showed dramatically improved phosphorus recovery efficiency compared to solvent extraction. This was in part due to the lower carbon content of the solid product, as the phosphorus to carbon molar ratio at both about 300 ° C. and about 350 ° C. was greater than about 0.25.

  Furthermore, the experiment at about 300 ° C. showed surprisingly improved results even compared to the experiment at about 350 ° C. Experiments at about 300 ° C have slightly lower phosphorus yields, but the amount of carbon and other materials in the solid product is about 30.8 wt% phosphorus concentration and about 0.56 phosphorus to carbon It was dramatically lower as indicated by the molar ratio. Without being bound by any particular theory, it is believed that the additional carbon present in the solid product at about 350 ° C. may be due to excessive reaction with the feedstock. In certain embodiments, the additional improved phosphorus recovery efficiency provided herein at a processing temperature of about 300 ° C. results in a phosphorus yield of about 90%, such as a phosphorus yield of about 87% to about 93%. By selecting the reaction conditions to be maintained, it can be maintained for other raw materials and at other reaction conditions.

The solid product produced by the experiment at about 300 ° C. was also analyzed using X-ray diffraction (XRD). The compounds that can be identified from the XRD spectrum included phosphate and phosphite. Some compounds identified in the scan are: Ca ₁₈ Mg ₂ H ₂ (PO ₄ ) ₁₄ ; Ca _28.8 Fe _3.2 (PO ₄ ) ₂₁ O _0.6 ; Mg (PO ₃ ) ₂ ; Ca ₂ P ₂ O ₇ ; and CaCO ₃ .

Example of Hydrothermal Treatment Desk Algal raw materials are treated under hydrothermal treatment conditions in a continuous flow reaction system. The reaction zone for hydrothermal treatment includes a coiled conduit surrounded by an oven. Conduit coiling increases the path length of the conduit in the oven. The flow rate in the conduit is selected so that the feed has a residence time in the reaction zone of about 15 minutes. The temperature of the reaction zone is about 350 ° C. The feedstock that passes through the reaction zone comprises a mixture of algae and water in a water to algae weight ratio of about 10: 1 to about 2.5: 1. The pressure in the conduit is determined in part by the water vapor pressure at the reaction temperature. If an optional catalyst is used (eg, included with the feed), this pressure is also increased by the addition of about 2.5 MPa of hydrogen gas. After passing through the coiled conduit, the flow is passed to the separator. Gas phase products, hydrocarbon products, aqueous products, and solid products are separated. The solid product can have a phosphorus content that is at least 85% of the initial phosphorus content of the feed. The solid product can also have a phosphorus content that is at least about 20% of the total solid product.

Claims (20)

Introducing a biomass feedstock having a water: biomass ratio of at least 1: 1 into the reaction zone, wherein the biomass feedstock has a phosphorus content;
Hydrothermally treating the biomass feedstock under hydrothermal treatment conditions effective to produce a multiphase product, wherein the multiphase product comprises at least about 80% of the phosphorus content of the biomass feedstock Including a solid portion;
Separating the multiphase product to produce at least a gas phase portion, a liquid hydrocarbon product, and the solid portion.   The method of claim 1, wherein the biomass feedstock comprises algae.   3. The method of claim 2, wherein the water: algae weight ratio is from about 2: 1 to about 10: 1.   The method of claim 1, wherein the effective hydrothermal treatment conditions include a temperature of about 150 ° C. to about 500 ° C. and a pressure of about 25 barg (about 2.5 MPag) to about 300 barg (about 30 MPag).   The method of claim 1, wherein the effective hydrothermal treatment condition comprises a temperature of about 250 ° C. to about 375 ° C. Said effective hydrothermal treatment conditions include hydrothermal treatment in the presence of a catalyst and the following conditions:
The treatment time is about 45 minutes to about 90 minutes when the temperature is about 250 ° C. to about 300 ° C .;
The treatment time is about 30 minutes to about 60 minutes when the temperature is about 275 ° C. to about 325 ° C., or the treatment time is about 15 minutes to about 30 when the temperature is about 300 ° C. to about 350 ° C. The method of claim 1, wherein one of the minutes is satisfied.   The method of claim 1, wherein contacting the algae-based material with water under effective hydrothermal treatment conditions does not result in a phase change of water.   The method of claim 1, further comprising separating the liquid hydrocarbon product to produce a fraction, at least 90% by weight of which has a boiling range of about 193 ° C to about 360 ° C.   The method of claim 1, wherein the solid portion has a phosphorus: carbon molar ratio of at least about 0.2.   The method of claim 1, wherein the solid portion comprises at least about 90% of the phosphorus content of the biomass feedstock and has a phosphorus: carbon molar ratio of at least about 0.25. Adding a polyvalent metal to a biomass raw material having a phosphorus content;
Contacting the biomass feedstock with water in the presence of the polyvalent metal under hydrothermal conditions effective to produce a multiphase product, wherein the multiphase product is phosphorous of the biomass feedstock Comprising a solid portion comprising at least about 80% of the content;
Separating the multiphase product to produce at least a gas phase portion, a liquid hydrocarbon product, and the solid portion.   The method of claim 11, wherein the polyvalent metal comprises Ca, Mg, Fe, or a combination thereof.   The method of claim 11, wherein separating the multiphase product to produce a solid portion comprises separating the multiphase product to produce a catalyst portion and an algae-based solid portion. .   The method of claim 13, wherein the algae-based solid portion comprises at least about 80% of the phosphorus content of the biomass feedstock and comprises a majority of the polyvalent metal.   The method according to claim 11, wherein in the step of contacting the biomass material with water under effective hydrothermal conditions, the polyvalent metal is added to the biomass material in a reaction zone. Contacting the algae-containing material having a phosphorus content with water under hydrothermal treatment conditions effective to produce a multiphase product, wherein the multiphase product is at least a phosphorus content of the algae-containing material. Including a solid portion comprising about 80%;
Separating the multiphase product to produce at least a gas phase portion, a liquid hydrocarbon product, and the solid portion;
Recycling the phosphorus from the solid part to an algae process. Recycling phosphorus from the solid portion,
The method of claim 16, comprising extracting phosphorus from the solid portion to form a phosphorus-based nutrient or nutrient precursor, and introducing the phosphorus-based nutrient or nutrient precursor into the algae growth process. The method described.   The method of claim 16, wherein the phosphorus-based nutrient or nutrient precursor is phosphoric acid.   17. The method of claim 16, wherein the water: algae weight ratio is from about 3: 1 to about 5: 1.   The method of claim 16, wherein the solid portion comprises at least about 90% of the phosphorus content of the biomass feedstock and has a phosphorus: carbon molar ratio of at least about 0.25.

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