RU70463U1 - REACTOR FOR PRODUCING UNCERTAIN HYDROCARBONS, PREFERREDLY, ETHYLENE - Google Patents

Abstract

The utility model relates to the field of hydrocarbon processing, namely, high-temperature reactors for producing unsaturated hydrocarbons, mainly ethylene. The reactor includes a cooled case with pipes for supplying an oxidizing agent and hydrocarbon feedstock, as well as a reaction chamber in communication with the quenching chamber. The reactor differs from the prototype in that it is additionally equipped with a hot gas generator connected to the inlet of the reaction chamber and equipped with a fuel supply pipe, an oxidizer supply pipe and a gas mixture ignition unit. The output of the hot gas generator narrows toward the reaction chamber to form a nozzle, and the hydrocarbon feed pipes are located in the zone of the critical section of the nozzle and are oriented radially. The technical result achieved is the creation of conditions for the combination of hydrodynamic and thermal degradation of hydrocarbons, providing a high percentage of ethylene yield.

Description

The utility model relates to the field of hydrocarbon processing, namely, high-temperature reactors for producing unsaturated hydrocarbons, mainly ethylene.

Known processing plant EP-300 for producing ethylene from gasoline fractions [Pyrolysis of hydrocarbons. Mukhina T.N., Barabanov N.L., Babash S.E. and others - M .: Chemistry, 1987, p.142-145]. The pyrolysis of raw materials is carried out in a tube furnace. The resulting reaction mixture is quenched in a quenching-evaporation apparatus and then subjected to compression, cleaning, drying, and then gas separation is carried out. To carry out these labor-intensive operations, complex, cumbersome and energy-intensive equipment is used, including superheaters, fractionation columns, separators, compressors, etc. As a result of multistage processing of gasoline fractions, up to 25% of ethylene and a small amount of acetylene and propylene are obtained at the outlet of the unit.

Known reactor for the processing of hydrocarbons [RF Patent 2290991, publ. 01/10/07]. In the reactor vessel there is a gas mixture ignition unit, a working body formation chamber, a pyrolysis chamber with a feed unit for the processed raw material and a quenching chamber. Pipes for supplying and removing reagents are connected to the housing. The reactor also contains a hot gas generator, the output of which is connected to the input of the chamber of the formation of the working fluid. The hot gas generator has an internal combustion chamber, which communicates with the ignition unit of the gas mixture and is equipped with a supply pipe for initiating combustion of gas. In the entrance

A part of the chamber for forming the working fluid has a collector with radial holes for supplying fuel. Between the chamber for the formation of the working fluid and the pyrolysis chamber, there are radial nozzles for supplying the processed raw materials. Between the pyrolysis chamber and the quenching chamber, there are radial nozzles for supplying hydrogen. The reactor has a complex structure and allows you to process heavy fractions of hydrocarbons - bottoms, tars, bitumen, fuel oil, etc.

As a prototype, a reactor was selected for producing acetylene from hydrocarbons [RF patent 2087185, publ. 08/20/97.]. The vertical reactor includes:

- a mixer for mixing oxidizer gas (oxygen) and raw materials (methane) heated to 650 ° C;

- a burner for igniting the mixture;

- a reaction chamber in which pyrolysis occurs;

- quenching apparatus.

By twisting the incoming mixture of hydrocarbons with oxygen on the blades of the burner, a helical motion of the hot gas stream in the tunnel of the reactor vessel and in the cavity of the quenching apparatus is ensured. The reactor has a divider, which is a sleeve coaxial to the walls of the quenching apparatus with nozzles at the upper end, which distributes the main cylindrical flow of reaction gases, converting it into a swirling annular flow. The reactor allows the processing of methane to produce mainly synthesis gas (over 80%) and an acetylene content in the pyrolysis gas of up to 9% vol.

Thus, there is a technical contradiction. The production of ethylene in tube furnaces makes it possible to obtain a significant yield of this product, however, the processing process is long, laborious, energy intensive, and requires modernization when switching from one type of raw material to another. On the other hand, the well-known high-temperature reactors are significantly simpler to operate and less energy-intensive, however, their operation yields unsaturated

hydrocarbons are much lower than in tube furnaces, so the yield of acetylene is less than 10%, and ethylene is generally a by-product, its share is 0.2-0.4%.

The utility model is based on the task of solving the existing contradiction and creating a high-temperature reactor of high productivity, universal in raw materials (liquid and gaseous hydrocarbons) and with a high yield of lower olefins (ethylene).

The technical result is the creation of conditions for a combination of hydrodynamic and thermal degradation of hydrocarbons, providing a high percentage of ethylene yield.

The problem is solved by changing the design of the reactor. The reactor includes a cooled case with pipes for supplying an oxidizing agent and hydrocarbon feedstock, as well as a reaction chamber in communication with the quenching chamber. The reactor differs from the prototype in that it is additionally equipped with a hot gas generator connected to the inlet of the reaction chamber and equipped with a fuel supply pipe, an oxidizer supply pipe and a gas mixture ignition unit. The output of the hot gas generator narrows toward the reaction chamber to form a nozzle, and the hydrocarbon feed pipes are located in the zone of the critical section of the nozzle and are oriented radially.

The essence of the utility model is explained in more detail in the following implementation example and is illustrated by the Figure, which schematically shows a longitudinal section of the reactor.

The reactor has a prefabricated water-cooled housing 1. The main components of the reactor are: hot gas generator 2, reaction chamber (pyrolysis chamber) 3, quenching chamber 4.

The hot gas generator 2 has an axial nozzle 5 for supplying fuel, for example, methane, a radial nozzle 6 for supplying an oxidizing agent, for example,

oxygen. The hot gas generator 2 is equipped with a unit for ignition of the combustible mixture, has a cylindrical combustion chamber and a nozzle 7, tapering towards the reaction chamber 3. The raw material supply pipes 8 are located in the zone 9 of the critical section of the nozzle, i.e. in the cross-sectional zone, in which the flow velocity is equal to the local speed of sound, and oriented radially.

The reactor operates as follows.

First, an oxidizing agent (oxygen) and fuel (methane) are supplied to the hot gas generator, and the resulting mixture is ignited using a plasmatron or an RF candle. Combustion occurs when the coefficient of excess oxidizer α <1. After reaching the operating mode, the hydrocarbon feed is supplied. As raw materials, it is possible to use liquid or gaseous hydrocarbons, for example, straight-run gasoline, gasoline fraction (boiling point 70-110 ° C), hydrocarbon raffinate. The processed raw materials are fed by radial jets into the zone of the critical section of the nozzle 7, i.e. to the area where the flow rate is close to the local speed of sound. The feed, driven by the flow from the hot gas generator, enters the reaction chamber 3. In the chamber 3, high-speed heating of the feed occurs, accompanied by the destruction of high molecular weight components. The turbulence of sound streams and the difference in kinetic and thermal pressures caused by superposition of axial and radial streams increase the degree of destruction of high molecular weight compounds. The operating modes in the chamber are T = 800-1200 ° C, pressure 3-6 ati. Further, the pyrolysis products enter the quenching chamber 4. The water entering the chamber 4 turns into steam, the temperature of the gas-vapor mixture decreases to 300-450 ° C and the pyrolysis process is stopped.

Separation into fractions of the resulting mixture is carried out in the traditional way.

Below is a table of material balances for raw materials and product obtained after separation.

Table Raw materials The composition of the resulting product Weight kg % of the mass. Straight run gasoline 31,200 kg Hydrogen 2215.2 7.1 Methane 5366.4 17,2 Ethylene 11793.6 37.8 Acetylene 3088.8 9.9 Ethane 1310.4 4.2 Propylene 4773.6 15.3 ΣС ₄ 1029.6 3.3 Losses 1622.4 5.2 TOTAL 31200 one hundred% Gasoline fraction (boiling point 70-110 ° С) 33600 kg Hydrogen 2761.9 8.22 Methane 6253.0 18.61 Ethylene 14169.1 42.17 Acetylene 4986,2 14.84 Ethane 719.0 2.14 Propylene 1985.8 5.91 ΣС ₄ 994.6 2.96 Losses 1730.4 5.15 TOTAL 33600 one hundred% 34800 kg hydrocarbon raffinate Hydrogen 3383.0 9.81 Methane 9,408.0 17.50 Ethylene 15486.7 40.33 Acetylene 3728.6 13.71 Ethane 1063.7 2.77 Propylene 2073.6 7.40 ΣC ₄ 937.0 3.44 Losses 2319.4 5.04 TOTAL 34800 one hundred%

The above and other numerous tests of the reactor showed that it allows the processing of various hydrocarbon feedstocks, both liquid and gaseous. The percentage yield of ethylene ranges from 38 to 50%, acetylene - 10-15%. The specific percentage is mainly determined by the physicochemical characteristics of the processed raw materials.

This application is described with some details to achieve clarity and understanding. Those skilled in the art, upon reading the description, may understand that some changes in the details are possible without going beyond the scope and the attached formula.

Claims (1)

A reactor for producing unsaturated hydrocarbons having a cooled casing with nozzles for supplying an oxidizing agent and hydrocarbon feeds and having a reaction chamber in communication with the quenching chamber, characterized in that it is further provided with a hot gas generator connected to the inlet of the reaction chamber and provided with a fuel supply pipe, a supply pipe oxidizer and the ignition unit of the gas mixture, the output of the hot gas generator narrows toward the reaction chamber with the formation of a nozzle, and the carbohydrate supply pipe native raw materials are located in the zone of the critical section of the nozzle and are oriented radially.