SU1058586A1 - Method of cleaning hydrocarbon mixture from acid components - Google Patents

Description

SP

00

ate

CX) O5

The article relates to the absorption methods of gas purification from acidic components and can be used in the oil, petrochemical, chemical and gas fields.

The processes of absorption purification of hydrocarbon c mixtures from acidic components are known in which propylene carbonate, polyethylene glycol dimethyl ether (DMEPEG) N is methylpyrrolidone, sulfolane, tributyl phosphate, etc, tl3 “

The lack of processes includes the difficulty of achieving a deep degree (cleaning up and increased solubility of hydrocarbons in absorbents. The presence of hydrocarbons in acid gases complicates their subsequent processing. In addition, the efficiency of such processes depends on the conditions of their execution.

The closest to the invention in its technical essence and the achieved result is a method for purifying hydrocarbon gases from acidic components, in which a 70-98 diethanolamine solution is used as an absorbent, the absorbent being deposited as a film on a solid carrier. Quartz sand, natural zeolite (clinoptilolite), C2 brick are used as a solid carrier.

The known method is characterized by a small amount of absorbent per unit volume of the apparatus, which makes it difficult to use this method on an industrial scale for cleaning large quantities of gas or gases containing more than 0.05% by volume, HjS, the inability to use for cleaning liquefied and liquid hydrocarbon fractions and low permissible linear velocities of gas and liquid flows, determined by the breakdown of the absorbent film from the surface of the solid carrier.

Thus, the application of a known process is associated with high capital investment in the cleaning process. At the same time, a small amount of absorbent deposited in the form of a film on the surface of a solid carrier, as compared with the total mass of sorbent used for gas purification, leads to a high specific energy expenditure for heating and cooling the solid carrier at the regeneration stage.

The aim of the invention is to increase the productivity of the process by increasing the sorption capacity of the scavenger.

The goal is achieved that according to the cleaning method

hydrocarbon mixtures from acidic components by absorption of their alkanolamine in, deposited on a solid carrier, followed by regeneration of a saturated absorber, alkanolamine is preliminarily immobilized on the inner surface of a synthetic or mineral adsorbent with a pore size of 80-800 A and a pore volume of 1.0-1.6 cm / g.

In this case, the absorption from gas mixtures was carried out at a space velocity of 1000-100.00 h, and from liquid at 10-50.

In addition, silica gel is used as a solid support.

The application of the absorption solution to the internal surface of the sorbent allows a significant increase (20-30 times in comparison with the prototype) the amount of the absorption solution per unit volume of the apparatus and at the same time by preventing film from the sorbent surface from significantly increasing the volumetric flow rates of gas and liquid mixtures. This leads to an increase in productivity, a decrease in the volume of the sorbent and the dimensions of the apparatus, used for cleaning, and consequently, a decrease in energy costs at the Regene stage ation of the sorbent. In addition, immobilization of the scavenger on the surface of the solid adsorbent causes an increase in the absorption capacity of 5-35 times due to the effective action of the active surface of the adsorbent at the interface with the alkanolamine solution.

EXAMPLE 1. Evaluation of the effectiveness of the proposed process for purifying petroleum gas from hydrogen sulphide is carried out by comparing it with a prototype. For this, silica grades of the following types are used as a sorbent: CX-423 CX-421, CX-424, KSK-1, previously dehydrated by calcination at 250 ° C, on the inner surface of each of which the solution of alkanolamine {monoethanolamine-MEA, diethanolamine - DEA is immobilized, MEA and DEA, respectively) directly in the adsorber (see Table 1. Composition gas, vol.%: N, 0.06; CO, 0.63; HjS 0.12; CH 81.42; 6.11; 6 , 87; 0.28, is sent to an adsorber with a diameter of 20 m, into which 30 cm of sorbent is loaded. The purified gas is discharged into the atmosphere. The cleaning process is continued until occurrence after a layer of breakthrough howling hydrogen sulfide concentration 0.0013 vol.%.

The results of the experiments are summarized in Table. one.

T a b l and D

Example 2. The purification of a mixture of liquid hydrocarbons (gasoline) is carried out in a continuous apparatus with a 3 liter stirrer. Gasoline (fraction 35-87 o has the following composition,% by weight;

, 83

36

CfeH, 32.07

, 81

Methylcyclopentane 3, 84

Cyclohexane 1.34

Dimethylcyclohexane 0.56

Benzene 3.93

Toluene 0.25

Hydrogen sulfide 0.1 15% solution of MEA is immobilized on the CX-423 sorbent.

The test was carried out under the following conditions:

Temperature, ° С

26 0.1

Pressure vnci Speed of the agitator, rpm 120 Volume of sorbent, cm 500 Volume velocity, h I -10 Residual content of hydrogen sulfide in purified gas gasoline

Indicators

Heat consumption for desorption Н „5, kcal

The amount of adsorbent, m

five

The detectable tube method is 0.02 May. %

Example 3. The experiment was carried out in the same apparatus as in Example 2. Crude oil was loaded into the vessel after

0 second stage separation, obtained from the oil and gas industry Bavlyneft

with a hydrogen sulfide content of 0.05 May,%, and a sorbent (CX-421, impregnated with 40% DEA solution, degree of impregnation 40%)

5 in the ratio. 50: 1. Conditions of experiment: Temperature, ° С 50 Pressure, MPa0,1

The number of revolutions me-. shawls, rpm80

0

Sorbent volume, see 500 Volume velocity, Serbidorum content in refined oil, as measured by tube oil

5 method, 0.02 May. %

The test results are shown in Table. 2, confirm an increase of 5-35 times the absorption capacity of the sorbent compared to

0 with the prototype, the possibility of using gas volumetric velocities that are 10 times higher than those allowed by the technology of the prototype, as well as the possibility of effective use

5 for the purification of liquid hydrocarbons. Table 2

Way

offer aekvly

prototype

256,000

256,000 12,360

Indicators

Bulk weight, kg / l. Adsorbent mass, kg

Heat consumption for sorbent heating, kcal

The total amount of heat for regeneration, kcal Anoschiz consumption of heat for regeneration by the proposed and known methods, carried out for the installation. purification of gas containing 0.3% HgS, with a capacity of 100 million nm / year, with a "duration of cleaning and regeneration cycle equal to 8 hours, showed that the process energy consumption is reduced by 6 times

Continued tabl, 2

1120000

72000 1360000 328000 The cost of cleaning by the proposed method decreased due to the size of the apparatus and the amount of adsorbent by lazy by 20-30 times, as well as by reducing energy costs at the stage of absorbent regeneration.

Claims (3)

1. METHOD FOR CLEANING HYDROCARBON MIXTURES FROM ACID COMPONENTS by absorbing them with alkanolamines deposited on a solid support, followed by regeneration of a saturated absorber) by increasing the sorption capacity of the absorber, alkanolamine is pre-immobilized on the inner surface of a synthetic or mineral adsorbent with a pore size of 80-800 A and a pore volume of 1.0-1.6 cm ³ / g. 2. The method according to π. 1, with the fact that the absorption from gas mixtures is carried out at a space velocity of 1000-10000 h ¹ , and from liquid at 10-15 h. '' 3. The method according to PP. 1 and 2, characterized in that as a solid carrier use silica gel. C 00 SP 00 C 1 1058586