RU2149885C1 - Method of processing petroleum and petroleum derivatives - Google Patents

Abstract

FIELD: petroleum processing. SUBSTANCE: invention, in particular, relates to processing crude oil, heavy oil residues, gas condensates, and natural gas. Process is carried out in presence of fine catalyst, which is preliminarily homogeneously dispersed with raw material to give mixture in which content of catalyst is 1 to 5 wt %. Waste catalyst is regenerated and returned into pyrolysis process. EFFECT: intensified processing with reduced power consumption. 3 cl, 2 dwg, 1 tbl

Description

 The invention is applicable in the petrochemical and chemical industries, specifically in the technology of oil refining, heavy oil residues, as well as gas condensates and natural gas.

Classical methods of thermocatalytic processing of oil and oil fractions are known (Petrochemist Handbook. T. 1. / Ed. Ogorodnikov SK - L .: Chemistry, 1978. - p. 54.), in which they carry out:
- atmospheric distillation of oil to produce gasoline, kerosene, diesel fractions and fuel oil;
- vacuum distillation of fuel oil to obtain vacuum gas oil or oily distillates;
- catalytic cracking of vacuum gas oil to produce gasoline;
- hydrocracking of a diesel fraction with purification from hydrogen sulfide;
- catalytic reforming of gasoline fractions to produce high octane gasoline;
- thermal pyrolysis of liquefied gases (ethane, propane and butane fractions) and low-octane gasoline to produce ethylene, propylene and acetylene.

The disadvantages of the mentioned classical schemes include the low depth of oil refining and oil fractions into motor fuel (not more than 65%) and unsaturated hydrocarbons (not more than 45% of the mass of raw materials). In particular, thermal pyrolysis has the following disadvantages:
- great dependence on the quality composition of raw materials;
- multi-stage and branching processes leads to a decrease in manageability and quality, as well as an increase in losses;
- a significant amount of resins is formed, moreover, with a heavier feedstock, for example, when switching from ethane to diesel fractions, the resin yield increases by a factor of 2;
- the transition to high-boiling fractions (kerosene and diesel) is associated with a decrease in ethylene yield and increased coking of the furnace coils.

 Recently, plasma-chemical methods for processing hydrocarbon raw materials have become increasingly popular. Known, for example, is a method for producing acetylene and ethylene from hydrocarbon materials using plasma-chemical reactions (Krapivina S. A. Plasma-chemical technological processes. - L.: Chemistry, 1981. - P. 182).

According to this method, gaseous and / or liquid hydrocarbons are sequentially subjected to plasma-chemical pyrolysis in a plasma-forming gas (industrial hydrogen or a mixture of hydrogen with methane), the soot and tar are purified from the pyrogas, pyrogas are compressed and dried, and finally the latter is separated from C ₃ hydrocarbons, C ₄ and above (acetylene homologs).

 Plasma-chemical methods provide a higher degree of processing (conversion of raw materials is 96 ... 98% of the mass), increase the processing depth to unsaturated hydrocarbons (more than 75%), allow the use of heavy oil fractions (kerosene and diesel) as raw materials, and also reduce the amount stages and reduce the branching of chemical processes.

A known method (US Pat. GDR N 270315 MKI ⁴ C 10 G 15/12 publ. 07.26.89), in which an oxygen-containing foreign plasma carrier is periodically briefly introduced into a plasma gas (hydrogen). The introduction of such a carrier can only eliminate the formation of resins (pyrolysis coke) without increasing the yield of the final product.

An increase in the yield of the final product is possible by combining the plasma-chemical and catalytic pyrolysis processes. So, according to a known method (Khudyakov G.N. et al. Effect of activating additives on the plasma-chemical process of formation of acetylene from natural gas. / II All-Union Symposium on plasma chemistry. - Abstracts. - Riga: Zinatne, 1975. - P. 243-246 ., prototype) an activating additive (K ₂ CO ₃ powder) is fed from the feeder into the plasma stream of hydrogen, the stream is mixed with jets of natural gas and the pyrolysis reaction is carried out, and then the reaction products are cooled. The described method allows you to slightly increase the yield of the final product, but does not allow the full use of activating additives, because after the introduction of the additive, the mixture of the plasma stream with natural gas is not homogeneous enough. Thus, the intensity of the processes of plasmachemical pyrolysis is reduced, the specific energy consumption is increased, and the consumption of additives is increased.

 The aim of the invention is to intensify the processes of plasma-chemical pyrolysis of oil and heavy oil residues, the transition to a closed system of complex processing of raw materials, as well as increasing the yield of the final product.

 The specified technical result during the implementation of the invention is achieved by the fact that in the known method of processing raw materials, including plasma-chemical pyrolysis in the presence of a catalyst, quenching of the pyrolysis products and their separation of the pyrolysis products, a finely dispersed catalyst is used, which regardless of the phase state (solid, liquid or gaseous) is pre-homogeneous dispersed with raw materials, and then the resulting mixture is subjected to plasmachemical pyrolysis. The mass of the catalyst is preferably 1-5% by weight of the feed. In addition, the used catalyst after separation of the pyrolysis products is regenerated and returned to the pyrolysis step.

Given that the plasma-chemical process is carried out at high temperature and ultrahigh speed (10 ^-5 ... 10 ^-4 s), the presence of a finely dispersed catalyst with a developed surface, homogeneously dispersed in the feedstock, increases the degree of conversion of the feedstock, reduces the specific energy consumption, which ultimately intensify the process of plasmachemical pyrolysis of oil and oil residues.

The process of implementing the proposed method for processing oil and oil residues (Fig. 1.) consists of the stage of preparation of the feedstock and the catalyst, in which feedstock 1 is mixed with a finely dispersed catalyst 2, the mixture is homogenized and sent to the next stage, where the homogenized mixture 3 is subjected to plasma-chemical pyrolysis to obtain pyrolysis products 4, which are sent to the separation stage. When separating the products of pyrolysis, the catalyst 5 is regenerated and returned to the stage of preparation of raw materials, and carbon black 6 is collected for further use. Pyrocondensate 7 is separated into unsaturated hydrocarbons 8 C ₂ -C ₄ , gasoline 9 and hydrogen methane fraction 10, returning the latter to the stage of plasma-chemical pyrolysis.

 To assess the industrial applicability of the method of processing oil and oil residues, an experimental verification of the processing technology was carried out, the scheme of which is presented in FIG. 2.

The diagram shows: feedstock 1, catalyst 2, a homogenized mixture of catalyst and feedstock 3, pyrolysis products 4, regenerated catalyst 5, carbon black 6, pyrocondensate 7, unsaturated hydrocarbons C ₂ -C ₄ 8, gasoline 9 and hydrogen methane fractions 10, capacity with mixer 11, dispenser 12, homogenizer 13, metering pump 14, plasma chemical pyrolysis reactor 15, hydrogen 16, quenching device 17, filter 18 for separating carbon black 6 and regenerated catalyst 5, refrigerator 19, separator 20.

 According to the presented technology, raw material 1 is fed into a container with a mixer 11, and using a metering pump 12, a pulverized, droplet-like or fog catalyst 2 is supplied. In this case, the catalyst 2 is mixed with the raw material, at the same time homogenizing the suspension with a special homogenizer 13, which operates along the external circuit " capacity 11 - homogenizer 13 - capacity 11 "for at least one hour. Then, the homogenized mixture of the catalyst with the feedstock 3 is sent via a metering pump 14 to the plasma-chemical pyrolysis reactor 15, where the plasma-forming gas, hydrogen 16, is also fed. In the reactor 15, the hydrocarbons that make up the feedstock are degraded by the action of a plasma jet and catalyst. Then the pyrolysis products 4 are sent to the quenching device 17, made in the form of a heat exchanger. Next, the pyrolysis products 4 are sent to the filter 18, where the pyrolysis condensate 7 is separated from carbon black 6 and the catalyst. Moreover, the regenerated catalyst 5 is returned to the stage of preparation of the raw materials in the dispenser 12. Finally, the pyrolysis condensate 7 is cooled in the refrigerator 19 and fed to the separator 20, where it is separated into unsaturated hydrocarbons 8, gasoline 9 and hydrogen methane 10 fractions, directing the latter to the plasma chemical pyrolysis stage in reactor 15 .

 During the experimental tests, the raw materials (oil and fuel oil) and the concentration of the catalyst were changed. The power of the plasma torch during oil refining was 13 kW, and during the processing of fuel oil - 12.4 kW. The results of the checks are given in table. 1. The same checks were carried out on other types of catalysts.

From the results it follows that:
- the combined use of plasmochemical and plasmocatalytic methods makes it possible to almost double the yield of unsaturated hydrocarbons in comparison with thermal pyrolysis;
- the use of finely dispersed catalysts homogeneously dispersed with raw materials reduces energy consumption by about 1.9 times;
- an increase in the concentration of pre-prepared catalyst in the feedstock reduces energy consumption while maintaining a high degree of yield of the sum of unsaturated hydrocarbons C ₂ -C ₄ .

 The above flow chart does not exhaust the options for its use using the described combination of essential features of the invention. Currently, a method of processing oil and oil residues is being prepared for industrial use.

Claims (3)

 1. A method of processing oil and oil residues, including plasma-chemical pyrolysis in the presence of a catalyst, quenching and separation of the pyrolysis products, characterized in that they use a catalyst homogeneously dispersed in the feed.  2. The method according to claim 1, characterized in that the catalyst is 1 to 5% of the mass of raw materials.  3. The method according to claims 1 and 2, characterized in that the catalyst is regenerated and returned to the pyrolysis stage.

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