FI124885B - Process for treating heavy residues of biological material and producing liquid fuels - Google Patents

Description

PROCESS FOR TREATING HEAVY RESIDUES ORIGINATING FROM MATERIAL OF BIOLOGICAL ORIGIN AND PRODUCING LIQUID FUELS

FIELD OF THE INVENTION

The present invention relates to a process for treating heavy residues originating from material of biological origin. The present invention also relates to a process for producing liquid fuels and fuel components from a biological source and a feedstock containing a biological source, where a heavy source is derived from a biological source process. The invention also relates to subjecting heavy residues from biological origin to hydrolysis followed by purification to obtain purified components which are subject to whereby the liquid fuels may be obtained.

BACKGROUND OF THE INVENTION

Feedstock of Biological Origin can be converted to liquid fuels by subjecting Feedstock to Catalytic hydroprocessing with gaseous hydrogen. The resulting product stream can be further fractionated for example by distillation to obtain liquid fuels and liquid fuel components.

Feedstock of Biological origin typically contains various impurities. The Feedstock can be refined and / or pretreated before feeding it to the process whereby the refined feedstock and heavy residues and impurities are obtained. There are various alternative methods available for carrying out purification and / or pretreatment of Feedstock of Biological origin.

An example of a feedstock of biological origin is tall oil, which is a major by-product of the Kraft Sulphate Pulping process. In the Kraft Pulping process, rosin acids and fatty acids, which occur for example in pine wood as free acids or their esters, are saponified with cooking liquor (Black Liquor) to their corresponding sodium salts. These salts, or their soaps, along with some neutral components are dissolved or suspended in the spent cooking liquor. This liquor is later concentrated and the soaps and neutral components are separated as tall oil soap skimmings. Most Kraft Mills which process Softwood Recover tall oil soap. This soap is usually acidified to produce crude tall oil (CTO). CTO can be burned to produce heat and power, or it can be utilized further for example by tall oil refining companies. CTO may also be converted into hydrocarbons suitable as liquid fuels and the like.

Tall oil refining companies typically separate certain compound groups (e.g., free resin and fatty acids) from tall oil or CTO, leaving residual called tall oil pitch (TOP). Typical percentage of this TOP from CTO is around 30-35% in tall oil fractionation processes. TOP consists mainly of neutral components, typically in the range of 70-90%, but usually it also contains resin acids, typically in the range of 10-20%, and residues of fatty acids, typically in the range of 2-5% , all percentages by weight. Neutral components consist mainly of sterols, stanols, sterol / stanol esters, polymeric acids, polymeric neutral substances, dimers, trimers and lignin derivatives. Also some resin acid esters can be found from TOP. TOP is typically burned in lime noble or CHP-plants.

In the production of liquid fuels, CTO may be pre-processed to remove excess metals and high boiling components (> 600 ° C), prior to subjecting it to catalytic hydroprocessing. CTO may be subjected to depitching where CTO is evaporated. In depitching a significant amount of valuable raw material is lost as a heavy residue (pitch). Said pitch is usually burned for energy production.

When evaporating CTO the amount of formed heavy residue can be at least from 5 to 15% calculated from the feed. The removed heavy residue (pitch) still contains neutral components, such as esters of sterols and stanols, resin acids and fatty acids, and part of the acids may be chemically bound to the neutral components. The heavy residue is typically directed to Burning.

To maximize the utilization of heavy residues derived from material of biological origin, such as TOP and heavy residues and pitch fractions derived from tall oil, obtained for example during depitching, evaporation and distillation, Converting particularly of neutral components contained in heavy residues, pitch and pitch fractions, into components such as sterols, stanols, fatty acids, resin acids, esters and alcohols would be needed.

SUMMARY OF THE INVENTION

According to the present invention, the present invention relates to a process for treating heavy residues from a biological source, where a mixture is formed from a feedstock comprising at least one heavy residue from a biological source, and an aqueous medium is subjected to hydrolysis. to obtain a hydrolyzed mixture followed by separating the hydrolyzed mixture into an organic phase and an aqueous phase, subjecting the organic phase to at least one purification treatment to obtain a purified product.

The process of the present invention for treating heavy residues from the biological origin provides purified products or components useful as starting materials in chemical processing.

According to another embodiment, the present invention relates to a process for producing liquid fuels or fuel components, wherein the mixture is formed from a feedstock containing at least one heavy residue from a biological source and is subject to hydrolysis to obtain a hydrolyzed mixture followed by separating the hydrolyzed mixture to an organic phase and an aqueous phase, subjecting the organic phase to a feedstock comprising at least one purification treatment to obtain a purified product and then subjecting the purified product to Catalytic Hydroprocessing whereby liquid fuels or components numbers are obtained.

Further, the process of the present invention for producing liquid fuels or fuel components provides bio-oils which may be used for example as fuels and fuel components.

Thus, an object of the invention is to provide a process for efficiently and economically converting potential materials contained in heavy residues from a biological origin, to provide useful starting materials and co-feeds for chemical processing, particularly in liquid fuel production, whereby the amount of materials which is usually discarded or burned, can be reduced.

Another object of the invention is to provide a process for the manufacture of liquid fuels and fuel components.

Still another object of the invention is to provide bio-oils based on heavy residues from materials of biological origin, and on renewable starting materials, for use as liquid fuels or fuel components.

DEFINITIONS

The term "hydroprocessing" refers here to the catalytic processing of organic material by all means of Molecular Hydrogen.

The term "neutral components" or "neutral fraction" or "neutral materials", often referred to as "unsaponifiables", refers here to all neutral organic components in the treatment or processing of a material of biological origin. Examples of said materials are tall oil pitch and tall oil materials contained therein.

Examples of components contained in an example of a tall oil pitch include sterols, stanols, sterol and stanol esters, polymeric acids, polymeric neutral substances, dimers, trimers, lignin derivatives, resin acids and fatty acids and esters.

The term "tall oil" or "crude tall oil" (CTO) refers to a product which is mainly composed of both saturated and unsaturated oxygen-containing organic compounds such as rosins, unsaponifiables, sterols, resin acids (mainly abietic acid and its isomers), fatty acids (mainly linoleic acid, palmitic acid, oleic acid and linolenic acid), fatty alcohols, sterols, other alkyl hydrocarbon derivatives, as well as inorganic impurities (alkaline metal compounds, Sulfur, Silicon, phosphorus, calcium and iron compounds) ). Tall oil also covers soap oil.

Tall oil or CTO refers to processed mixtures of naturally occurring compounds extracted from wood species such as birch, pine, spruce and Aspen. It is typically obtained from the acidification of crude tall oil soap from Kraft and Sulphite Pulping processes used in paper making. The handling and cooking of the wood causes the break down of the triglyceride structures and hence the tall oil or CTO does not contain any significant amounts of triglycerides. The composition of tall oil or CTO varies depending on the specific wood species.

The term "liquid fuels" refers to fractions or cuts or blends of hydrocarbons having distillation curves standardized for fuels, such as for diesel fuel (middle distillate from 160 to 380 ° C, EN 590), gasoline (150-210 ° C, EN 228), aviation fuel (160 to 300 ° C, ASTM D-1655 jet fuel), kerosene, naphtha, etc.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic flow diagram representing one embodiment of the process for the manufacture of liquid fuels.

Figure 2 shows distillation Curves of pitch before and after processing.

DETAILED DESCRIPTION OF THE INVENTION

The invention is based on the idea of utilizing effectively the valuable components contained in the materials of biological origin Examples of such heavy residues are TOP, TOP fractions and heavy residues and / or fractions obtained in depitching, evaporation and distillation of tall oil materials, CTO, and the like. It has been found that valuable components can be converted to starting materials and co-feeds which are suitable for chemical processing such as catalytic hydroprocessing for providing liquid fuels or fuel components. The yields of liquid fuels or liquid fuel components can be increased and the amounts of residual materials directed to Burning can be significantly reduced.

In the process of the invention, heavy residues derived from materials of biological origin are subjected to hydrolysis, where particularly neutral components contained in the heavy residues are hydrolyzed to yield valuable compounds. When the heavy residue originates from tall oil materials, compounds such as resin acids, fatty acids, sterols and stanols may be obtained. Fractions comprising valuable compounds can be separated and subsequently directed to at least one purification treatment together with Feedstock consisting of Biological origin to yield purified products.

The product obtained from the purification treatment can be directed to further chemical processing. Suitably the purified product is directed to catalytic hydroprocessing for obtaining liquid fuels or fuel components.

In the case of heavy residues arising from tall oil or tall oil materials, surprisingly high amounts of valuable compounds can be separated from the heavy residues for further processing. It was found that even up to 50% by weight of heavy residues, such as TOP or pitch fractions, can be converted and / or separated and suitably utilized effectively for example in Catalytic Hydroprocessing. Particularly fatty acids and resin acids which are chemically bound to the neutral components in the pitch can be released with mild hydrolysis followed by purification, such as evaporative treatment, and then may be further directed to Catalytic Hydroprocessing.

The process in accordance with the present invention for treating heavy residues from a biological source comprises a step of subjecting a mixture to a feedstock comprising at least one heavy residue from a biological source and an aqueous medium to hydrolysis at a temperature from 10 to 280 ° C and a pressure from 0 to 70 bar to obtain a hydrolyzed mixture, b) separating the hydrolyzed mixture into an organic phase, and c) subjecting the organic phase and Feedstock comprising at least one material of biological origin at least one purification treatment to obtain a purified product.

Said purified product may be used as feedstock in chemical processing, such as Catalytic Hydroprocessing.

Suitably the heavy residue originates from tall oil material.

The process in accordance with the present invention for producing liquid fuels or fuel components comprises steps a) - c) as described above and additional steps d) -0-

The process in accordance with the present invention, for producing liquid fuels or fuel components, comprises the steps of a) subjecting a mixture formed by a feedstock to at least one heavy residue from a biological source and to an aqueous medium to a hydrolysis. a temperature from 10 to 280 ° C and a pressure from 0 to 70 bar to obtain a hydrolyzed mixture, b) separating the hydrolyzed mixture into an organic phase, and c) subjecting the organic phase and Feedstock comprising at least one material d) Feeding the purified product into the purified product, d) Feeding the purified product into the at least one catalytically active hydroprocessing reaction phase, resulting in contact with at least one hydroprocessing catalyst, e) Treating the purified product catalytically with hydrogen in the reactor system to cause hydrodeoxygenation, hydrogenation, isomerization ion and cracking of the components contained in the purified product to provide a hydroprocessing product, and f) recovering at least a fraction of the hydroprocessing product as a liquid fuel or fuel component.

Heavy residue

The heavy residue may originate from any material of biological origin and may be obtained from any evaporative treatment including depitching and distillation of said material. Suitably the heavy residue originates from tall oil material. Said heavy residues may be selected from TOP (tall oil pitch, which may be obtained for example from CTO), heavy residues and pitch fractions obtained from any evaporative treatment including depitching and distillation of tall oil materials, and heavy evaporation residues obtained from the purification treatment carried out as evaporative treatment in the process of invention, and any combinations of claims.

The tall oil material comprises one or more of the tall oil components, tall oil derivatives and any combinations thereof, including CTO, TOFA (tall oil fatty acids), tall oil soap, etc. Tall oil material refers particularly to a by-product of Kraft pulping of wood, such as coniferous wood, birch, Aspen, etc. Tall oil material is typically a mixture of fatty acids, resin acids, neutral compounds, and continuous components from wood such as coniferous wood. The turpentine components of tall oil are mainly composed of C10H16 terpenes.

Hydrolysis

In accordance with the present invention, heavy residues, and particularly organic compounds such as those present in the neutral components, are subject to hydrolysis whereby the valuable compounds can be separated and subsequently directed to at least one purification treatment. In the case of heavy residues originate from tall oil materials, phases comprising for example resin acids, fatty acids, sterols and stanols can be separated.

In the process of the invention, in step a) a mixture formed from a feedstock comprising at least one heavy residue from a material of biological origin and an aqueous medium is subjected to hydrolysis at a temperature from 10 to 280 ° C and under a pressure from 0 to 70 bar to obtain a hydrolyzed mixture.

The aqueous medium is selected from water, and mixtures of water with at least one alkali metal hydroxide and at least one C1-C4 alcohol.

The aqueous medium is used in the volumetric ratio with respect to the Feedstock from 1:20 to 20: 1.

In a case only water is used as an aqueous medium, the volumetric ratio of water to Feedstock is suitably from 1: 2 to 10: 1. Tap water and suitably demineralized or deionized water may be used.

The alkali metal hydroxide is suitably NaOH or KOH. The amount of alkali metal hydroxide in the mixture is from 1 to 20%, suitably from 5 to 15% by weight. The Cl-C4 alcohol is suitably methanol, ethanol, butanol or a combination thereof. The amount of alcohol in the mixture ranges from 50 to 96%, suitably from 80 to 95% by volume. The amount of alcohol needed may be estimated based on the amount of heavy residue. Particularly suitably methanol is obtained as a by-product from pulp manufacturing is used.

The hydrolysis may be carried out in the presence of a Catalyst comprising at least one cationic amine compound. Particularly in the case where water is used as the aqueous medium the hydrolysis reaction can be enhanced with said catalysts. In case of amine Catalyst is used, the volumetric ratio of water to Feedstock is suitably from 1:20 to 10: 5, suitably 1:15 to 1:10.

Suitable cationic amine compounds are water-soluble cationic amine soaps including primary, secondary and tertiary mono- and polyamines, such as aliphatic, including cycloaliphatic, mono- and polyamines, and mixtures. Said amine catalysts are used in amounts of 0.001 - 0.5% by weight, calculated based on the Feedstock, suitably 0.01 - 0.2%.

The amine compounds may contain up to 20, suitably above 6 carbon atoms in their structural formula. For example, suitable amines are isopropylamine, n-propylamine, diisopropylamine, n-butylamine, di-n-butylamine, tri-n-butylamine, triethylamine, cyclohexylamine, ethylene diamine, diethylene triamine, triethylene tetramine, tetraethylene pentamine, etc., Heterocyclic N containing mono- and polyamines, for example, morpholine, N-methylmorpholine, 4- (2-aminoethoxy) ethylmorpholine, 2- (4-morpholinylethoxy) ethanol, bis-2- (4-morpholinyl) ethyl ether, piperazine, N - aminoethylpiperazine, N-hydroxy-ethyl-piperazine, pyridazine, pyrrole, pyrrolidine, pyridine, piperadine, pyrimidine, pyridazine, etc. Also long chain fatty acid amines are useful such as Cocoa fatty acid primary amines, dilauryl secondary amine and N, N-dimethyl dodecyl tertiary amine.

Suitable quaternary cationic amine soaps include aliphatic and aryl amines having from 10 carbon atoms to 22 carbon atoms such as dodecyl phenol, quaternary amine soaps, cetyl trimethyl ammonium bromide, cetyl trimethyl ammonium chloride, dodecyl trimethyl ammonium chloride, and nonyl trimethyl ammonium chloride.

The mixture of feedstock comprises at least one heavy residue from a material of biological origin and the aqueous medium may be formed using any mixing method and any mixing device which provides vigorous mixing or agitation. Suitably the mixing is carried out with a homogenizer, with a dispersing pump, or a high shear mixing device. The mixing may be carried out prior to or simultaneously with the hydrolysis.

In the case of mixing of the feedstock with the aqueous medium is carried forward to hydrolysis, a temperature of 5 to 120 ° C, suitably 70 to 120 ° C is used. In the case of an aqueous medium, water is mixed at a temperature of 5-100 ° C, suitably 70-99 ° C is used.

The mixing / homogenizing and hydrolysis may be carried out in the same vessel or the mixing or homogenizing vessel or pipeline and the hydrolysis may be carried out in a separate hydrolysis vessel or Reactor.

If necessary, the mixed / homogenized mixture may be heated prior to the hydrolysis step, suitably using heat exchangers or the like.

The hydrolysis of the mixture is carried out at a temperature of 10-280 ° C, suitably at 60-280 ° C. The hydrolysis of the mixture is carried out under pressure from 0-70 bar, suitably from 0.1-70 bar. The hydrolyzed mixture is obtained.

When only water is used as the aqueous medium, the hydrolysis is suitably carried out at a temperature of 220-280 ° C. Suitably a pressure of 25-70 bar is used. The hydrolysis is suitably carried out for 30 min to 10 hours.

When an amine catalyst is used together with water as an aqueous medium, the hydrolysis is suitably carried out at a temperature of 80-180 ° C, suitably 80-125 ° C. The pressure is from 0 to 5 bar, suitably from 0.1 to 1.5 bar. The hydrolysis is suitably carried out for 10 min to 3 hours.

When the aqueous medium comprises at least one alkali metal hydroxide and at least one alcohol, the hydrolysis of the mixture is carried out at a temperature of 60-200 ° C, suitably 100-200 ° C. A pressure of 1-30 bar, suitably 1-3 bar is used. The hydrolysis is suitably carried out from 30 min to 10 hours, suitably from 45 min to 2 hours.

Suitably, the pH of the hydrolyzed mixture is adjusted to the range of 2-3 with an acid selected from strong acids such as H2SO4, HNO3, etc. Suitably H2SO4 is used. When only water is used as an aqueous medium, without a Catalyst, the pH of the hydrolyzed mixture is suitably adjusted to 5.8 to 6.9 if necessary.

If necessary the hydrolyzed mixture, after optional pH adjustment, may be cooled prior to the subsequent separation step, suitably using heat exchangers or the like. Suitably the hydrolyzed mixture is cooled to a temperature below 100 ° C, suitably to 65-95 ° C.

Separation

The hydrolyzed and optionally cooled mixture is separated at a temperature below 100 ° C, suitably at 65-95 ° C, into an organic phase and an aqueous phase. The separation may be carried out by any known means of separation. The organic phase comprises typically water-soluble compounds, volatile organic compounds, free acids, alcohols and unsaponifiable components, and the aqueous phase comprises typically water-soluble compounds, alkali metal salts and the like. The aqueous phase is suitably directed to waste water treatment.

The separation may be carried out by any suitable separation means such as hydrodynamic separation, gravimetric separation, and coalescent separation. Suitably decantation methods and devices may be used.

Purification

The separated organic phase and Feedstock comprise at least one material of biological origin being directed to at least one purification treatment to obtain a purified product.

The material of biological origin is selected from the group consisting of (a) plant fats, plant oils, plant waxes; animal fats, animal oils, animal waxes, fish fats, fish oils, fish waxes, and b) recycled food grade fats and oils, and fats, oils and waxes obtained by genetic engineering, and c) fats, oils and waxes derived from algae , molds, yeasts, fungi and / or other microorganisms capable of producing said compounds; and (d) mixtures of said biological feed materials.

According to the present invention, the material of biological origin is selected from the group consisting of fish oils such as Baltic herring oil, salmon oil, herring oil, tuna oil, anchovy oil, Sardine oil, and mackerel oil; plant oils such as rapeseed oil, colza oil, canola oil, tall oil, crude tall oil, sunflower seed oil, soybean oil, corn oil, hemp oil, linseed oil, olive oil, cottonseed oil, mustard oil, palm oil, peanut oil, castor oil, Jatropha seed oil, Pongamia pinnata seed oil, palm kernel oil, and coconut oil; and animal fats such as Lard, Tallow, rendered Lard and rendered Tallow, and waste and recycled food grade fats and oils, as well as fats, waxes and oils produced by Genetic Engineering; animal waxes such as bee wax, Chinese wax (insect wax), shellac wax, and lanoline (wool wax); plant waxes such as carnauba palm wax, ouricouri palm wax, jojoba seed oil, candelilla wax, esparto wax, japan wax, rice bran oil, terpenes, terpineols and triglycerides or mixtures of waxes.

In one embodiment of the invention, the material of the biological origin consists of nonedible plant oils or components, for example obtained from by-products from the forest industry. In one embodiment of the invention, the material of biological origin is composed of tall oil materials. Tall oil material consists of tall oil components, tall oil derivatives and any combinations, including CTO, TOFA etc.

The purification treatment is selected from bleaching, degumming, washing, ion exchange and evaporative treatments and any combinations.

The purified product obtained from the purification treatment may be directed to further chemical processing, suitably to the catalytic hydroprocessing for the liquid fuels or fuel components.

According to one embodiment, degumming may be used for purification, particularly for the removal of metal complexes. Degumming may be performed by washing the organic phase and Feedstock comprising at least one material of biological origin suitably at 90-105 ° C, 300-500 kPa, with an acid such as H3PO4 followed by treatment with a base such as NaOH and soft water and separating the formed gums. A major amount of metal components can be removed during this degumming stage.

According to another bleaching may be used for purification. In bleaching the organic phase and the feedstock comprises at least one material of biological origin can be heated and mixed with natural or acid-activated bleaching clay. Bleaching can remove various impurity traces and reduce the oxidation tendency. Bleaching can be carried out under vacuum to minimize possible oxidation.

According to one embodiment of the organic phase and Feedstock comprising at least one material of biological origin may be subject to washing with water or dilute acid solution.

According to one embodiment, the organic phase and the feedstock comprise at least one material of biological origin may be subjected to ion-exchange treatment.

According to one embodiment, the organic phase and the feedstock comprise at least one material of biological origin may be subjected to evaporative treatment. In the evaporative treatment, the organic phase and the feedstock consist of at least one material of the biological origin are fed into the evaporative unit, comprising at least three evaporators, where the organic phase and the feedstock comprise the biological substance are subject to the evaporative treatment to obtain the purified product. (an effluent consisting of the purified organic phase) and a heavy evaporation residue. The resulting heavy evaporation residue is recycled at least partly to the Feedstock containing heavy residue.

In evaporative treatment, in feed to evaporation unit, weight ratio of organic phase to material of biological origin is from 0.1: 99.9 to 20:80, suitably from 0.2: 99.8 to 15:85, particularly suitably from 0.2 : 99.8 to 10:90. Suitably, in the feed to the evaporation unit, not more than 15% by weight of the feed is formed from the recycled heavy evaporation residue obtained by the process.

By evaporation is meant here any suitable separation method for separating two or more components from each other, such as gases from a liquid, which separation method is based on utilizing the differences in vapor pressure of the components. Examples of such separation methods are evaporation, flashing and distillation. Examples of suitable evaporation methods are those using thin film evaporation technology. The evaporators can thus be selected from the group of thin film evaporator, falling film evaporator, short path evaporator, plate Molecular still and any other evaporator using thin film evaporation technology. The evaporation unit can comprise one, two, three, four or more evaporators which can be either of the same type or different type and are selected independently from the suitable separation methods presented above. The evaporative treatment is carried out in an evaporation unit comprising evaporators arranged in series.

The evaporation in the process of the invention consists of three, four or more evaporation steps.

Water, metals and solids, for example lignin, compounds comprising example metals, compounds Mostly of Na, Fe, P, Si, sulfates e.g. Na2SO4 and H2SO4 are removed in evaporative treatment.

The evaporation is accomplished in three steps, i.e. the evaporation unit consists of three evaporators, water and light components are first evaporated from the feed material in the first evaporation step in order to make the following evaporation steps more efficient. In the second and third evaporation steps, the pitch containing the residual fraction is minimized by evaporating the liquid product of the first evaporation step. The advantage of using a three step evaporation unit is that the second evaporation step can be a small and cheap evaporator that removes the light components from the material. The following third evaporation step can also be smaller and cheaper than the second step in two-step evaporation. The heavy fraction from the second evaporation step is directed to the third evaporator, from which the heavy evaporation residue containing mainly heavy polymeric components and the pitch is recycled to the hydrolysis, typically containing mainly the fatty acids obtained as a purified product, which may without directed chemical processing such as Catalytic Hydroprocessing.

Thus, according to one embodiment of the invention, the evaporation is carried out in three steps by feeding the organic phase (obtained from hydrolysis) and Feedstock comprises at least one material of biological origin to an evaporation unit comprising three evaporators. In three step evaporation, in the first step, water and light components are removed at a temperature of 50-250 ° C and a pressure of 5-100 mbar, suitably at a temperature of 120-200 ° C and a pressure of 10- 55 mbar. The evaporator is suitably a thin film evaporator or a falling film evaporator. In the second step, the liquid product from the first evaporation step is evaporated at a temperature of 180 to 350 ° C and a pressure of 0.1 to 40 mbar, suitably at a temperature of 200 to 270 ° C and a pressure of 0.1 to 20 mbar. . The evaporator is suitably a plate Molecular still or a thin film evaporator. Particularly suitably the evaporator is a thin film evaporator. The distillate of the second step is recovered as purified material and the liquid fraction is directed to the third evaporation step. In the third step, the liquid product from the second evaporation step is evaporated at a temperature of 200 to 450 ° C and a pressure of 0 to 50 mbar, suitably at a temperature of 300 to 390 ° C and a pressure of 0.01 to 10 mbar. . The evaporator is suitably a short path evaporator or a thin film evaporator. The heavy evaporation residue from the third step is recycled to the feed to hydrolysis and the effluent (the purified material recovered from the third step) is combined with the purified material from the second step to form the purified product. The purified product can be used as feed material for Catalytic Hydroprocessing.

According to another embodiment of the invention, evaporation is accomplished in four steps by feeding the organic phase from hydrolysis and Feedstock comprising at least one material of biological origin to an evaporation unit comprising four evaporators. In the four step evaporation, the organic phase and the feedstock comprising the biological origin are evaporated in the first fraction comprising water and light components, and the second fraction comprising heavy components and residues. The second fraction is evaporated in a second evaporator to produce a third fraction consisting of water and low boiling light compounds and a fourth fraction comprising heavy components and residues. The fourth fraction is evaporated in the third evaporator to produce the fifth fraction consisting mainly of fatty acids and the sixth fraction comprising heavy components and residues. The sixth fraction is evaporated in the fourth evaporator to produce the seventh fraction consisting mainly of fatty acids and an eighth fraction comprising heavy evaporation residue which is recycled to the feed to hydrolysis. The fifth and seventh fractions are combined and recovered as a purified product which may be used as a feed for Catalytic Hydroprocessing.

In the four step evaporation the first evaporator may be a falling film evaporator or a plate Molecular still or a thin film evaporator, suitably a falling film evaporator (FFE) or plate Molecular still is used, especially suitably a FFE is used. The feed material (organic phase and Feedstock comprising material of biological origin) is evaporated in the first evaporator at a temperature from 80 to 150 ° C, suitably from 90 to 120 ° C. The evaporation is carried out under pressure from 40 to 80 mbar, suitably from 45 to 65 mbar. The first fraction consists of water and some light components are separated and the second fraction consists of the heavier components and residues, such as fatty acids, resin acids, neutral substances, etc. is directed to a second evaporator. The falling film evaporator removes effectively the major amount of water present in the feed material, typically more than 50% by weight; the second fraction containing the remaining components is directed to the second evaporator.

The second evaporator is a thin film evaporator or a short-path evaporator or a plate Molecular still, suitably a thin film evaporator is used. The second evaporator operates at a temperature from 180 to 250 ° C, suitably from 190 to 220 ° C. A pressure of 40 to 80 mbar, suitably from 45 to 65 mbar is used. The third fraction containing water and low boiling light hydrocarbon components, said fraction having a boiling point of 100-210 ° C, suitably 100-170 ° C at normal pressure, is removed and the liquid fourth fraction is directed to the third evaporator. When CTO is used as a material of biological origin, Crude Sulfate Turpentine (CST) is removed in the third fraction with water. Particularly suitably the first and second evaporators are operated under the same pressure. Suitably the same pressure vessel or pressure line is used.

The liquid fraction from the second evaporator is led to the third evaporator. The thin film evaporator or plate Molecular still or short path evaporator can be used, suitably the third evaporator is a short path evaporator. The third evaporator typically operates at a temperature of 200 to 350 ° C, suitably from 250 to 300 ° C. A pressure of 0.01 to 50 mbar, suitably 0.5 to 10 mbar, more suitably 1 to 5 mbar and particularly 2 to 3 mbar is used in the third evaporator. The fifth fraction (distillate) is typically mainly (more than 50% by weight) fatty acids separated and suitably fed to the Reactor feed tank and the sixth fraction (liquid phase) is led to the fourth evaporator.

The fourth evaporator may be a short path evaporator or a plate Molecular still, suitably a short path evaporator is used. Typical operating conditions include a temperature of 250 to 400 ° C, suitably from 290 to 360 ° C. A pressure of 0.01 to 10 mbar, suitably 0.01 to 5 mbar, more suitably 0.1 to 2 mbar is used. From the fourth evaporator, the seventh fraction (distillate) is obtained and combined with the distillate fraction is obtained from the third evaporator to the yield purified product which can be used as feed for catalytic hydroprocessing and it can be fed to the hydrogenation Reactor feed tank. The eighth fraction (the heavy evaporation residue, a very viscous fraction), amounting typically about 5% from the original feed, is recycled at least partly to the Feedstock containing heavy residue.

According to one embodiment, the purification treatment is an evaporative treatment consisting of three or four evaporative steps and heavy residues obtained from any third or fourth evaporation step are recycled to feedstock comprising at least one heavy residue from a material of biological origin.

According to one embodiment of the invention, prior to the evaporative treatment, the organic phase from the hydrolysis and the material of biological origin may optionally be subject to additional flashing prior to feeding to the first evaporator. Flashing may be carried out using any suitable carrier, for example using heat-exchanger-expansion vessels where the volatile components are released.

An advantage of purifying with three or four or more step evaporation is that the boiling takes place in a more controlled continent because of the low boiling light components, i.e. components having a boiling point of 150-210 ° C, suitably 150-170 ° C, at normal pressure, do not cause so much "carry over", i.e. migrating of the compounds having a boiling point range at the higher end of the above boiling point Ranges as well as impurities to the vapor in the subsequent evaporation step. The light components can be, if desired, directed to hydroprocessing or refined further in another process or used further.

Catalytic hydroprocessing

According to one embodiment of the invention, the purified product from purification treatment is directed to catalytic hydroprocessing.

D) Feeding the purified product into a reactor system comprising at least one catalytically active hydroprocessing reaction phase resulting in contact with at least one hydroprocessing catalyst, e) Treating the purified product catalytically with hydrogen in the Reactor system to cause hydrodeoxygenation, hydrogenation, isomerization, and cracking of the components contained in the purified product to provide a hydroprocessing product, and f) recovering at least a fraction of the hydroprocessing product as a liquid fuel or fuel component.

According to the present invention, between purification treatment and hydroprocessing there may be optionally an additional purification. The additional purification may be realized using a guard bed, i.e. a separate pretreatment purification bed prior to the hydroprocessing. The additional purification may also be realized by a purification bed or section located in connection with the hydropocessing Reactor.

The process of the present invention for producing liquid fuels or fuel components optionally comprises treatment of the purified product in one or more guard beds. The one or more guard beds can be arranged either to separate guard bed units and / or in the hydroprocessing Reactor. The guard bed has the task of acting against harmful substances in the feed. The guard bed is typically activated with gamma aluminum oxide or a commercially available Purifying Catalyst. The guard bed material may also comprise Catalyst materials that are capable of catalyzing hydroprocessing reactions. The Catalyst material may comprise the same material / materials that are used in the hydroprocessing Reactor. The guard bed or guard bed units can retain both solid and solvated impurities from the feed of biological origin, such as silicon-based antifoaming agents, a tall oil process and harmful chemical elements. The guard bed and / or the guard bed units can be heated, unheated, pressurized or unpressurized, fed with hydrogen gas or without hydrogen gas. Suitably the guard bed and / or the guard bed units are heated and unpressurised.

There are basically two types of guard beds, i.e. active and inactive guard beds. The active guard beds take part in the purification of the feed and change the chemical composition of the feed and they can be placed either in separate guard bed units or inside the hydroprocessing Reactor itself. In an active, the active guard bed consists of only activated gamma aluminum oxide. In another embodiment, the active guard bed comprises Catalyst materials capable of catalyzing hydroprocessing reactions, such as Catalyst containing metals from Group VI and / or VIII or mixtures or combinations, which Catalyst is capable of converting Biological feed material to fuel components. In another embodiment, the active guard bed comprises a NiW Catalyst or a mixture or a combination of several thin layers or beds of NiW and NiMo catalysts on a support selected from AI2O3, zeolite, zeolite-Al203 and AI2O3-S1O2.

The inactive guard beds only take part in the purification of the feed. These guard beds comprise suitable passive or inert materials. The separate guard beds can be multiplied meaning there is one or more guard beds in a stand-by mode in parallel or in series with the guard bed (s) in use.

The process of the present invention comprises hydroprocessing the purified product in the presence of at least one Catalyst to form a mixture of fuel components. The hydroprocessing in the present invention can be done in one, two, three or more steps.

According to one step of the present invention, hydroprocessing is done in one step. The Catalyst is a Catalyst capable of hydrodeoxygenating, hydrogenating, isomerizing, ring opening and cracking a purified Biological material to form a mixture of fuel components. In this embodiment, the Catalyst is selected so that it hydrogenates the double bonds of the purified Biological material fed to the hydroprocessing. The Catalyst removes heteroatoms of the feed molecules, especially oxygen, by hydrogenation. The Catalyst has the ability to hydrogenate the olefinic bonds of the compounds in the feed, opening at least one of the bicyclic rings, and cracking the side chains of hydrocarbon chains. In other words, hydrocarbons are hydrogenated, isomerized and / or cracked in a single step. The cracking / isomerizing are controlled by process variables such as pressure and / or temperature and by the properties of the Catalyst, for example by controlling its acidicity. At the same time, sulfur compounds are reduced to hydrogen sulfide. The Catalyst Contained In The Hydroprocessing Reactor Is Selected From The Catalyst Containing Metals From Group VI And / or VIII Of The Periodic System Or Mixtures Or Combinations, Which Catalyst Is Capable Of Converting Biological Feed Material To Fuel Components In A Single Step. In a suitable embodiment of the invention, the catalyst comprises NiW, typically on a support selected from AI2O3, zeolite, zeolite-AbCh, and AI2O3-S1O2. NiW is an AI2O3 support.

In a still further embodiment of the invention where the hydroprocessing is carried out in one step, the Catalyst is a mixture or a combination of a NiW Catalyst with a further Catalyst. Said further Catalyst may be selected from any catalyst containing metals from group VI and / or VIII of the periodic system such as Ni, Co, Mo, Pt, Pd, or mixtures or combinations, such as NiMo and C0M0, typically on a support selected from AI2O3, zeolite, zeolite-AhCh, or AI2O3-S1O2. Catalyst is NiMo with an AI2O3 support. In one suitable embodiment of the invention, the Catalyst is a combination or a mixture of several thin layers or beds of NiMo and NiW catalysts.

According to another embodiment, the hydroprocessing is performed in two steps. In the first step, the fatty acids contained in the feed material of biological origin are converted to n-paraffins and in the second step, the resulting n-paraffins are isomerized and / or cracked. In the first step, the Catalyst is used which has a suitable metal such as Group VIII and / or VIB of the Periodic System may be used. Suitable catalysts are supported by Pt, Pd, Ni, NiMo or CoMo catalysts, with suitable support such as AI2O3 and / or S1O2. The Catalyst is used in the isomerizing step for example of a Molecular sieve containing a metal component of noble metals from Group VIII, such as Pt and / or Pd, or a NiW Catalyst is a suitable support such as AI2O3, zeolite, zeolite -Al203 or AI2O3-S1O2.

In order to function and stay active the hydroprocessing catalysts used in the present invention needs organic sulfur. Therefore, when the feed to the hydroprocessing does not contain sulfur or its sulfur concentration is too low, additional sulfur is fed to the step of hydroprocessing. The additional sulfur can be fed to the hydroprocessing step together with the feed or it can be fed separately to the hydroprocessing step. The additional sulfur can be supplied to the process in gaseous form as hydrogen sulfide, or it can be any material that produces hydrogen sulfide in the process, such as organic sulfur compounds such as dimethyl disulfide. The amount of additional sulfur depends on the amount of sulfur contained in the feed. A person skilled in the art is able to determine the amount of sulfur needed without undue burden. Generally, the H2 feed / hhS ratio is maintained over about 0.0001, suitably over about 0.001.

The Catalyst material must be activated before it is effective and taken into use. The activation consists of several steps, one of which is treating the Catalyst with an activating sulfur compound, for example dimethyl disulfide. The procedure of activating thus comprises sulfiding of the Catalyst. The activation of catalysts is common knowledge in art and will thus not be discussed here in detail.

The Catalyst contained in the present invention can be in any suitable form. The Catalyst used in the present invention can be diluted with Silicon carbide, aluminum oxide, glass beads, less active Catalyst and / or inert material. The Catalyst used in the present invention can also be undiluted. The Catalyst can be in Catalyst bed and the bed can be graded by adjusting the activity, particle shape and / or size of the used Catalyst. The diluting and grading of the Catalyst helps in controlling the exothermic balance of the reaction.

The hydroprocessing can be carried out in any kind of reactor, column, vessel, container, tube or pipe which is suitable for hydroprocessing.

The hydroprocessing is carried out at a temperature range from about 280 ° C to about 500 ° C, suitably from about 330 ° C to about 430 ° C. The Capability of Opening the Fused Ring Structures is also the desired property of the Catalyst.

The hydroprocessing is carried out at a pressure of about 20 to about 200 bar, more suitably at about 50 to about 200 bar, more suitably at about 70 to about 120 bar.

The feed is pumped to the hydroprocessing Reactor at a desired speed. Feed rate WHSV (Weight Hourly Spatial Velocity) of feed material is typically in the range of about 0.2 to about 2.5, preferably from about 0.3 to 1.5.

The amount of hydrogen gas needed was determined by the amount of feed. The suitable amount of hydrogen can be determined by a person having ordinary skills in the art. Typically, the relation Fhfeed / feed is in the range of about 350 to 3,000 Nl / I, preferably from about 500 to 2,500 Nl / I. (Nl = Normal per liter). According to the present invention, the gaseous compounds separated from the liquid compounds are hydrogen gas, hydrogen sulfide, light fuel gases, mainly lighter than C5 hydrocarbons.

The process of the present invention may further comprise the step of recycling the portion of the liquid hydrocarbon compounds obtained from the separation or fractionation back to the hydroprocessing.

According to the present invention, the resulting liquid fuel or fuel components are a fraction containing gasoline and / or naphtha and a fraction containing middle distillate.

Figure 1 is a schematic diagram of a process for producing liquid fuels in accordance with one embodiment of the invention. In this embodiment, in the first step Feedstock 10, comprising at least one heavy residue from a material of biological origin, heavy evaporation residue 120 and an aqueous medium 20 are fed to a vessel 100 where the homogenization mixture is carried out, the homogenized mixture 30 is directed to heat exchanger 101 for heating and then to hydrolysis Reactor 200 where the mixture 30 is hydrolyzed. From the hydrolysis Reactor 200, the hydrolyzed mixture 31 is directed to the heat exchanger 102 for cooling, followed by directing the cooled mixture 31 to the separation vessel 201, wherein the aqueous phase is 40 (containing water soluble compounds, alkali metal salts and the like) and an organic phase 50 (containing organic compounds and water-insoluble compounds) are separated. The organic phase 50 and the feedstock comprising material of biological origin 60 are directed to an evaporator unit 700, where the water and light compounds are separated and withdrawn as stream 70 and the liquid stream 80 is directed to the second evaporator 400 The distillate 90 (comprising typically fatty acids) is directed to the hydroprocessing unit 800 and the liquid stream 110 is directed to the third evaporator 500. The heavy residue stream 120 from the evaporator 500 is recycled to the homogenization vessel 100 and the effluent 130. is combined with distillate 90 forming purified product which is directed to the hydroprocessing unit 800, to the hydroprocessing product Reactor 600. The heavy residue 140 is directed to burning and the hydroprocessing product 150 is directed to further fractionation steps if desired.

The following examples are illustrative of embodiments of the present invention, as described above, and are not intended to limit the invention in any way.

Examples

Example 1 A mixture was formed of 25 g of pitch (heavy residue stream obtained by evaporation from a CTO in three evaporators) and 100 ml of an aqueous 0.5 N KOH in ethanol (95%) and the mixture was then hydrolyzed at approx. 80 ° C under NTP for 7 hours. The mixture was cooled and the pH was adjusted to 2-3 with 30% H2SO4 (10 mL). Water (approx. 100 ml) was added to the mixture and it was extracted 3 times with diethyl ether and hexane 1: 1, followed by washing with water. Distillation Curves of the pitch used as starting material (highest curve) and after hydrolysis treatment as instructed above (middle curve) are shown in Figure 2, as well as evaporated (3-step evaporation) tall oil as reference (lowest curve). (SimDis / FID, internal standard cholesterol, and sample concentration were same in all runs).

Some properties of the pitch (starting material) and treated pitch are presented in table 1 below.

Table 1

From table 1 it can be seen that the amounts of acids and sterols were increased, whereby the amounts of valuable starting materials were available for further chemical processing.

The present invention has been described with reference to specific embodiments. It is, however clear to those skilled in the art that the process (es) may be varied within the bounds of claims.

Claims (25)

A process for treating heavy residues from a material of biological origin, said process comprising the steps of: a) hydrolysis at a temperature of 10 to 280 ° C and a pressure of 0 to 70 bar for a mixture of a feedstock comprising a heavy material of biological origin; a residue and an aqueous medium, the aqueous medium being selected from mixtures of water with at least one alkali imidazole and at least one C1-C4 alcohol and water to form a hydrolyzed mixture, and if the water is used as an aqueous medium , hydrolysis in the presence of a catalyst comprising a cationic amine compound, b) separating the hydrolyzed mixture into an organic phase and an aqueous phase, c) carrying out at least one purification of the organic phase and the feedstock comprising a material of biological origin treatment to obtain a purified product. The process of claim 1, wherein the material of biological origin is selected from the group consisting of: a) vegetable fats, vegetable oils, vegetable waxes; animal fats, animal oils, animal waxes; fish oils, fish oils, fish waxes, and (b) recycled food grade fats and oils, and fats, oils and waxes derived from genetic engineering; and (c) fats, oils and waxes derived from algae, molds, yeasts, fungi and / or other micro- from organisms capable of producing said compounds; and d) mixtures of said materials. The process according to claim 1 or 2, wherein the material of biological origin is tall oil material. A process according to any one of claims 1 to 3, wherein the purification treatment is selected from bleaching, resin and pitch removal, washing, ion exchange, evaporation treatments and combinations thereof. The process of any one of claims 1 to 4, wherein the purification treatment is an evaporation treatment comprising three, four or more evaporation steps. The process of any one of claims 1 to 5, wherein the purification treatment is an evaporation treatment comprising three or four evaporation steps, and the heavy residues from the third or fourth step are recycled to a feed comprising at least one heavy residue from a material of biological origin. The process according to any one of claims 1 to 6, wherein the heavy residue is selected from tall oil oils, heavy residues obtained from the evaporation treatment of tall oil materials, picric fractions, and combinations thereof. A process according to any one of claims 1 to 7, wherein the hydrolysis is carried out at a temperature of 60 to 200 ° C and a pressure of 1 to 30 bar, and the aqueous medium is selected from mixtures of water with at least one -C4 with alcohol. The process according to any one of claims 1 to 7, wherein the hydrolysis is carried out in the presence of a catalyst comprising a cationic amine compound at a temperature of 80-180 ° C and a pressure of 0-5 bar, and water is used as the aqueous medium. A process according to any one of claims 1 to 8, wherein the pH of the hydrolyzed mixture is adjusted to a range of 2 to 3 by means of an acid. The process of any one of claims 1 to 10, wherein the evaporator is selected from thin-film evaporators, drop-film evaporators, short-path evaporators, and plate molecule distillers. A process for the preparation of liquid fuels or fuel components, comprising the steps of a) hydrolysis at a temperature of 10 to 280 ° C and a pressure of 0 to 70 bar for a mixture of a feedstock comprising a heavy residue from a material of biological origin and an aqueous medium; which aqueous medium is selected from mixtures of water containing at least one alkali imidazole and at least one C1-C4 alcohol and water to form a hydrolyzed mixture and, if water is used as an aqueous medium, hydrolysis from the cation in the presence of a catalyst comprising an amine compound, b) separating the hydrolyzed mixture into an organic phase and an aqueous phase, c) subjecting the organic phase and the feed comprising a material of biological origin to at least one purification treatment to d) feeding the refined product to the reactor system comprising at least one catalytically active hydrogen processing reaction step, wherein said purified product is contacted with at least one hydrogen processing catalyst; and (f) recovering at least one fraction of the hydrogen processing product as a liquid fuel or fuel component. The process of claim 12, wherein the material of biological origin is selected from the group consisting of: a) vegetable fats, vegetable oils, vegetable waxes; animal fats, animal oils, animal waxes; fish oils, fish oils, fish waxes, and (b) recycled food grade fats and oils, and fats, oils and waxes derived from genetic engineering; and (c) fats, oils and waxes derived from algae, molds, yeasts, fungi and / or other micro- from organisms capable of producing said compounds; and d) mixtures of said materials. The process of claim 12 or 13, wherein the material of biological origin is tall oil material. The process of any one of claims 12 to 14, wherein the purification treatment is selected from bleaching, resin and resin removal, washing, ion exchange, evaporation treatments and combinations thereof. The process of any one of claims 12 to 15, wherein the purification treatment is an evaporation treatment comprising three, four or more evaporation steps. The process of any one of claims 12 to 16, wherein the purification treatment is an evaporation treatment comprising three or four evaporation steps, and the heavy residues from the third or fourth step are recycled to a feed comprising at least one heavy residue from a material of biological origin. The process according to any one of claims 12 to 17, wherein the heavy residue is selected from tall oil oils, heavy residues obtained from the evaporation treatment of tall oil materials, picric fractions and combinations thereof. A process according to any one of claims 12 to 18, wherein the hydrolysis is carried out at a temperature of 60 to 200 ° C and a pressure of 1 to 30 bar, and the aqueous medium is selected from mixtures of water with at least one -C4 with alcohol. A process according to any one of claims 12 to 18, wherein the hydrolysis is carried out in the presence of a catalyst comprising a cationic amine compound at a temperature of 80-180 ° C and at a pressure of 0-5 bar, the water is used as an aqueous medium. A process according to any one of claims 12 to 19, wherein the pH of the hydrolyzed mixture is adjusted to 2-3 with an acid. The process of any one of claims 12 to 21, wherein the evaporator is selected from thin-film evaporators, drop-film evaporators, short-path evaporators, and plate molecule distillers. A process according to any one of claims 12 to 22, wherein the hydrogen processing is carried out in a single step and the catalyst is a Group VI and / or VIII metal or alloy or combination catalyst capable of converting the biological feed material into fuel components. The process of claim 23, wherein the catalyst is a NiW catalyst or a mixture or combination of NiW and NiMo catalysts with a support selected from Al2O3, zeolite, zeolite-AhCl, and Al2O3-S1O2. A process according to any one of claims 12 to 24, wherein the hydrogen processing is carried out in two steps and in the first step the catalyst is a catalyst containing Group VII and / or VIB metals of the Periodic Table on a suitable support capable of converting hydrocarbons to n-paraffins NiW selected catalyst supported on Al2O3, zeolite, zeolite-Al2O3 or Al2O3-S1O2.