RU2167184C1 - Process of thermal cracking of sulfide oil residues - Google Patents

Abstract

FIELD: oil refining. SUBSTANCE: invention refers to thermal cracking of sulfide residues in particular. Proposed process includes heating of starting material in tubular furnace and keeping of products of cracking in reaction chamber with their subsequent separation. Flow of low-pressure gas in compressed in jet device whose working medium is flow of gas of higher pressure released out of this plant. EFFECT: simplified stage of compression of low-pressure gases of cracking, reduced energy consumption.

Description

 The invention relates to the field of oil refining, in particular to thermal cracking processes of sulphurous oil residues.

A known method of thermal cracking of sulphurous oil residues, including cracking weighted feed (tar) at a temperature of 450-490 ^o C in one furnace, and light reflux (fraction 200-350 ^o C) in a second furnace at 540-545 ^o C followed by exposure of both flows removed from these furnaces in the reaction chamber and separation of the cracked products into gas, gasoline, gas oil and cracked residue, directing it to boiler fuel. The light part of the gas-liquid cracking mass on top of the high-pressure evaporator enters the distillation column, where at the top temperature of 190-210 ^o C under pressure of 0.8-1.2 MPa gasoline and cracking gases are removed, which are separated in the gas separator after cooling, and then the gases are directed to the gas fractionation unit. The heavy part of the gas-liquid cracking mass of the high-pressure evaporator enters the low-pressure evaporator, where at the top temperature of 190-195 ^o C under pressure 0.15 - 0.35 MPa, gas oil and cracking gases are removed, which are also separated in the gas separator after cooling, these cracking gases are sent to the torch afterburning or through a flame arrester to a separate nozzle in a tubular cracking furnace (Refinery Handbook edited by GA Lastovkin et al., L .: Chemistry 1986, p. 81-92).

 The disadvantage of this method is the incomplete utilization of cracking gases due to the low pressure of the separated cracking mass in the low pressure evaporator.

 The closest to the claimed object in technical essence and the achieved effect is a method of processing gaseous products of thermal decomposition of oil raw materials by compressing them with a piston compressor in 2 stages up to 1-3 MPa and output for further processing (Japanese application N 3-60875, C 10 G - 9/00, published on September 16, 91).

 The disadvantage of this method is the inefficiency of the gas compression process by a piston compressor during the processing of hydrogen sulfide-containing cracking gases due to their high aggressiveness, which leads to metal corrosion and the rapid failure of the compressor used, as well as the cost of electricity for its operation.

 The invention is aimed at simplifying the stage of compression of low pressure cracking gases and reducing energy consumption.

 This is achieved by the fact that in the method of thermal cracking of sulphurous oil residues, including heating the feed in a tube furnace and holding the cracked products in the reaction chamber, followed by separation of the cracked products into gas, gasoline, gas oil, cracked residue and compression of the cracked gaseous products, low gas compression pressure is carried out in a jet apparatus, the working fluid of which is a gas stream of higher pressure, derived from the same installation.

 The method is illustrated by the following examples.

Example 1. Tar of Arlan oil with a density of 999.6 kg / m ³ , with a sulfur content of 4.1%, is subjected to thermal cracking at 455 ^o C at the industrial plant 15/1 of Ufaneftekhim OJSC, gases containing hydrogen sulfide 15 are isolated from cracking products, 7%, methane 7.4%, hydrocarbons: C ₂ 16.9%, C ₃ 21.9%, C ₄ 25.9%, C ₅ 12.2%. The gas stream of higher pressure from the first gas separator with a temperature of 50 ^o C, a flow rate of 2.11 kg / s under a pressure of 1 MPa is used as a working fluid in a jet apparatus for compressing a low pressure stream; output from the second gas separator with a temperature of 50 ^o C, a flow rate of 0.23 kg / s under a pressure of 0.2 MPa. The total gas flow at the outlet of the jet apparatus has a pressure of 0.49 MPa.

 Example 2. The same raw materials as in example 1 are processed in a similar manner at a pressure of a low pressure gas stream of 0.25 MPa. The total gas flow has an outlet pressure of 0.54 MPa.

 Example 3. The same raw materials as in example 1 are also processed at a low pressure gas pressure of 0.30 MPa. The total gas flow has an outlet pressure of 0.60 MPa.

 Example 4. The same raw materials as in example 1 are also processed at a low pressure gas pressure of 0.35 MPa. The total gas flow has an output pressure of 0.64 MPa.

 As a result of the implementation of this method of compressing a low-pressure gas stream described in examples 3, 4, the total gas stream has a fairly high pressure (0.6 - 0.64 MPa), which allows it to be transported to a 30/4 hydrocarbon gas desulfurization unit, where hydrogen sulfide is captured by a solution of monoethanolamine, and the purified hydrocarbon gas after installation 30/4 is sent for further processing.

 The implementation of this method will avoid the corrosion of the compressor equipment and will not require energy consumption for its operation.

Claims (1)

 The method of thermal cracking of sulphurous oil residues, comprising heating the feed in a tube furnace and holding the cracked products in the reaction chamber, followed by separation of the cracked products into gas, gasoline, gas oil, cracked residue and cracking gas compression, characterized in that the low pressure gas stream is compressed in a jet apparatus, the working fluid of which is a gas stream of a higher pressure, discharged from the same installation.