SU1406074A1 - Method of storing petroleum products in a tank with utilization of vapors - Google Patents

Abstract

The invention relates to the storage of petroleum products and can be used in the petrochemical and refining industries, as well as in other areas associated with the storage of highly evaporated products. The purpose of the invention is to reduce losses and energy consumption during storage and increase operational reliability. The method consists in condensing the vapor-air mixture by passing in a bubbling mode through a layer of cooled oil. A new method is to pre-cool the vapor-air mixture that enters the capacitor-condenser up to 0 ° C and the use of air that has not been condensed during the bubbling process, which results in the drying of the mixture and the rational use of cold air. 1 hp fgly, 1 willows. (L

Description

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The invention relates to the storage of petroleum products and can be used in the petrochemical and petroleum refining industry, as well as in other branches associated with the storage of highly evaporated liquid products.

The purpose of the invention is to reduce losses and energy consumption during storage and increase operational reliability by eliminating the formation of ice plugs.

Precooling the vapor-air mixture entering the capacitor-condenser to О С allows reducing the moisture content of the mixture entering the sparging to 0.6%, i.e. to almost zero partial pressure of water vapor, thereby significantly reducing the likelihood of overlapping flow sections of pipe fittings with ice and frost, and, consequently, increasing the operational reliability of the method.

Pre-cooling to O C eliminates the formation of ice more precisely than ice plugs, and in devices where the mixture is pre-cooled, the gas drops out as moisture from the mixture as a liquid, which can be relatively easily separated from condensate. The desiccation of moisture in the same condition is explained by the absence of supercooling of the mixture relative to the freezing point of water.

Thus, the operational reliability of the method for utilization of oil product vapors increases. I

Pre-cooling of the vapor-air mixture with air cooled during sparging allows the mixture to partially dry and thereby increase the operational reliability of the method, condense the oil product vapor to an equilibrium concentration corresponding to the temperature of the previously cooled air-steam mixture. as well as reduce the heat content of the mixture entering the bubbling, and, consequently, reduce the energy costs of condensation of the remaining steam in the mixture, which has significantly less neck heat content

The drawing shows a schematic diagram of an installation for carrying out the proposed method.

The installation includes a tank 1 filled with oil, the gas space of which by pipe 2 is connected to a heat exchanger 3, the tank-condenser 4, the inlet of which by pipe 5 is connected to a heat exchanger, and the free space by a heat-insulated pipe 6 is connected to a heat exchanger 3, a sump 7, a condensate collector 8 connected overflow tubes 9 with a settling tank 7 and a capacitor-capacitor 4, and a pump 10, the inlet of which is connected to the condensate collector 8, and the outlet to the reservoir 1.

The method is carried out in the following manner.

The vapor-air mixture displaced from tank 1 through pipe 2 enters the heat exchanger 3, where it is cooled down to 0 ° C with cold air coming from the condenser tank

4 on the heat-insulated pipeline 6. Cooling the mixture in the heat exchanger 3 is accompanied by condensation of water and oil product vapors to concentrations corresponding to О С, i.e. oil product vapors partially condense, and water vapor almost completely. The dried vapor-air mixture, which has a lower heat content and a lower vapor concentration of the oil product, through the pipeline

5 enters the capacitor 4 filled with cooled petroleum product. The bubbling pass through the cooled petroleum product, the mixture is cooled to a temperature corresponding to zero partial vapor pressure of the petroleum product, as a result of which the petroleum product vapors are completely condensed, and the air (inert non-condensing component of the mixture) is cooled and through the heat-insulated pipeline 6 enters the heat exchanger 3, where gives off its cold vapor-air mixture and is emitted into the atmosphere. Condensate oil and water from the heat exchanger 3 flows into the sump 7, where they are separated. For overflow pipes 9 condensate oil from the sump 7 and the capacitor-condenser

4 flows into the condensate trap 8, from where as it is accumulated by the pump 10 it is fed to the reservoir 1. The level of oil in the capacitor-condenser 4 is 200-250 mm, ensuring that 14

The passage of the entire vapor-air mixture through the heat exchanger and the tank-condenser, excluding the activation of the safety (breathing) valves operating at a pressure of 200 mm of water. pillar. If necessary, the capacitor-condenser with a heat exchanger can serve several tanks filled with the same petroleum product.

The use of the proposed installation and the implementation of the method allows for the complete utilization of the vapors of petroleum products; significantly reduce (by 20-30%) the electrical energy consumption for vapor condensation; to prevent emissions of petroleum product vapor into the atmosphere, thereby solving the problem of environmental protection; reduce the likelihood of the valve arteries passing through by ice and hoarfrost.

The theoretical rationale for a significant decrease in the moisture content of the vapor-air mixture when cooled to 0 ° C is the almost zero partial pressure of water vapor at zero temperature.

Example 1. The amount of moisture contained in the steam-air mixture

tew ts | 0.95 and temperature but p

(O L1

L9 ..-. 7,9,4-.

the amount of water in 1000 m of the mixture, kg;

partial pressure of water vapor in the mixture; pressure of water vapor;

air humidity; absolute pressure of the mixture.

g

719.4

0.95-0.04241 1.02

1 0, 95-0,04241

1.02

 29.5 kg / 1000 m

Thus, pre-cooling the vapor-air mixture to 0 ° C allows 86% of the moisture in the mixture to be removed.

The reduction in the energy intensity of the method can be justified by considering the heat balance equation for the capacitor-capacitor

de

QH QB + Qnn QM

+ Q

to

QS Qnn-QK is the heat that must be removed from the oil in the tank-condenser; warm dry air; heat superheated vapors of petroleum product ;:

heat condensation of petroleum product vapor

(5ts SVSRV (T, -T) С „Cf„ (T, -T ,,) + C „,,

T -51

T -

i g

where Gg ,, the weight of air and oil vapor in the displaced vapor-air mixture; Cpc, Cpj is the heat capacity of air and

vapors;

T | - temperature of the displaced mixture;

vapor temperature at the saturation line;

temperature maintained in the capacitor-condenser corresponding to zero partial pressure of oil product vapor. Example 2. The flow rate of an air-steam mixture with a large breath is 200; the temperature of the mixture is 50 ° C; the temperature on the line, corresponding to a vapor concentration of 0.4-38 ° C.

The temperature maintained in the capacitor-condenser is 50 ° C. 1 our air capacity C |

 Pb

. ™ 4S c Thermal capacity of gasoline vapor C

pn

60

 2

The residual moisture content of the mixture after cooling to O C

SG 719.4

one

0.0061 1.02

1 - 4.2 kg / 1000 мз.

1-0.0061 1.02

6

, - ..%.

Steam heat is hidden

g 272 Sch. L kg J

Substituting the original data into the equation of heat balance, we get Q 75000 kJ, which corresponds to the power of the refrigeration unit of 20 kW.

d „„ 5000kJ; Q 56,000 kJ; , C "14000 kJ, or 4 kW, i.e. on oh10

Air cladding goes - 20% of energy.

Example 3. The temperature at lithium saturation, corresponding to the condensation of vapors of the oil product C 0.2, is 19 C.

The rest of the data in example 2. After calculating yoluchay.

Q, 53,000 kJ, or 15 kW; Q, „“ 6500 kJ; Q ft27500 kJ; Q "19000 kJ, or 5.5 kW, i.e. 36% of energy goes to air cooling

From the above examples it can be seen that the use of cold air, which condenses during processing, makes it possible to reduce energy consumption for utilization of oil product vapors by 20–30% compared with the prototype.

Claims (2)

1. A method for storing petroleum products in a tank with the utilization of oil vapors f heating products, including vapor condensation by passing-in the cutting process of bubbling the steam-air mixture from the tank through a condenser filled with oil from the tank,. the temperature of which is maintained below the temperature of the oil product and the crystallization temperature of the latter, characterized by 4TOj in order to reduce losses and energy consumption during storage and improve operational reliability by eliminating the formation of ice plugs, before condensation, the air-steam mixture 15 cool to the OS, 2. Method POP.1, characterized in that the vapor-air mixture is cooled by an air medium cooled during bubbling. cool to the OS, 2. Method POP.1, characterized in that the vapor-air mixture is cooled by an air medium cooled during bubbling. one