Production system for co-production of acetic acid from blast furnace gas

Abstract

The utility model discloses a production system for co-production of blast furnace gas and acetic acid. The production system comprises a purification device, a heating furnace, a CO2 separation and purification device, a CO2 electrolysis device, a pressure swing adsorption device, a gas mixing device, a methanol synthesis device and an acetic acid synthesis device, an inlet of the purification device is communicated with a blast furnace gas pipeline, an outlet of the purification device is communicated with a fuel inlet of the heating furnace, and a flue gas outlet of the heating furnace is sequentially communicated with the CO2 separation and purification device and the CO2 electrolysis device; a synthesis gas outlet of the CO2 electrolysis device is communicated with an inlet of the pressure swing adsorption device, and an H2 outlet of the pressure swing adsorption device is sequentially communicated with the gas mixing device, the methanol synthesis device and the acetic acid synthesis device; and a CO outlet of the pressure swing adsorption device is respectively communicated with the gas mixing device and the acetic acid synthesis device. The system is high in energy utilization rate, heat after methanol synthesis is fully utilized, methanol directly enters the acetic acid synthesis device without condensation, and methanol reaction heat is utilized to directly perform carbonylation reaction with CO to obtain a product acetic acid.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of blast furnace gas resource utilization, especially a blast furnace gas co-production acetic acid production system. BACKGROUND

[0002] Acetic acid is also known as acetic acid in industry, as a kind of more environmentally friendly organic acid, in the chemical production process belongs to important basic chemical raw material, can be used for acetic acid ethyl ester, acetate fiber, chloroacetic acid, acetate, terephthalic acid, vinyl acetate monomer and polyvinyl alcohol etc. Hundred kinds of downstream product synthesis. In 2003, the global acetic acid production was only 810,000 tons, but to 2018, the global acetic acid can reach 1939.4 million tons / year production capacity, so the market demand space of acetic acid is very large, and the development prospect is very good.

[0003] Blast furnace gas is a combustible gas by-produced in the process of blast furnace ironmaking, is an important secondary energy, main component is CO, CO2, N2, also contains a certain amount of COS, H2S and dust etc., at present, mainly as self-use fuel gas of steel industry, on the one hand, the utilization value of gas is low, on the other hand, the large amount of CO2 emission after combustion causes environmental pollution problem. China is a big steel production country, and the steel industry can produce more than 100 billion cubic meters of blast furnace gas every year, so the gas resources are very rich, therefore, the resource utilization of steel plant gas becomes the focus of attention of the extension of the industrial chain of the steel enterprise to create benefits. Based on this, it is urgent to develop a resource utilization system of blast furnace gas to help the steel industry to reduce carbon. CONTENT OF UTILITY MODEL

[0004] The technical problem to be solved by the utility model is to provide a blast furnace gas co-production acetic acid production system, so that the blast furnace gas is resource utilization.

[0005] In order to solve the above technical problems, the technical scheme adopted by the utility model is: including purification device, heating furnace, CO2 separation and purification device, CO2 electrolysis device, pressure swing adsorption device, gas mixing device, methanol synthesis device and acetic acid synthesis device;The inlet of the purification device is communicated with the blast furnace gas pipeline, and the outlet is communicated with the fuel inlet of the heating furnace, and the flue gas outlet of the heating furnace is communicated with the CO2 separation and purification device and the CO2 electrolysis device in turn;The synthesis gas outlet of the CO2 electrolysis device is communicated with the inlet of the pressure swing adsorption device, and the H2 outlet of the pressure swing adsorption device is communicated with the gas mixing device, the methanol synthesis device and the acetic acid synthesis device in turn;The CO outlet of the pressure swing adsorption device is communicated with the gas mixing device and the acetic acid synthesis device respectively.

[0006] Further, the O2 outlet of the CO2 electrolysis device is communicated with the oxygen inlet of the heating furnace.

[0007] Further, a first compressor is arranged on a pipeline between the heating furnace and the CO2 separation and purification device.

[0008] Further, a second compressor is arranged on a pipeline between the CO2 electrolysis device and the pressure swing adsorption device.

[0009] Further, a third compressor is arranged on a pipeline between the gas mixing device and the methanol synthesis device.

[0010] Further, a fourth compressor is arranged on a pipeline between the pressure swing adsorption device and the acetic acid synthesis device.

[0011] The beneficial effects produced by the above technical solution are as follows: firstly, the O2 generated by electrolysis is sprayed into the heating furnace to make the blast furnace gas fully burn, and the energy contained in the blast furnace gas is effectively utilized; secondly, the problem of a large amount of flue gas emission caused by the blast furnace gas combustion is solved, and the CO2 in the flue gas is converted into synthesis gas through the electro-catalysis technology; the energy utilization rate of the present application is high, the heat after methanol synthesis is fully utilized, the methanol directly enters the acetic acid synthesis device without condensation, and the product acetic acid is obtained by the carbonylation reaction of methanol with CO using the reaction heat of methanol. The raw material route of the present application is novel, energy-saving and environment-friendly, is a great innovation in acetic acid production, solves the problem of difficult utilization of blast furnace gas, produces high-value chemicals, helps carbon emission reduction of the steel industry, and brings economic benefits. BRIEF DESCRIPTION OF DRAWINGS

[0012] The present application will be further described in detail below in combination with the drawings and specific embodiments.

[0013] Figure 1 is a structural schematic diagram of the present application. DETAILED DESCRIPTION

[0014] Figure 1The production system for co-production of blast furnace gas and acetic acid comprises a purification device, a heating furnace, a CO2 separation and purification device, a CO2 electrolysis device, a pressure swing adsorption device, a gas mixing device, a methanol synthesis device, an acetic acid synthesis device and a compressor. The inlet of the purification device is connected with a blast furnace gas pipeline, and the outlet is connected with the fuel inlet of the heating furnace. The flue gas outlet of the heating furnace is connected with the inlet of the first compressor, the outlet of the first compressor is connected with the inlet of the CO2 separation and purification device, and the outlet of the CO2 separation and purification device is connected with the inlet of the CO2 electrolysis device. The CO2 electrolysis device is provided with a synthesis gas outlet and an O2 outlet. The synthesis gas outlet of the CO2 electrolysis device is connected with the inlet of the second compressor, the outlet of the second compressor is connected with the inlet of the pressure swing adsorption device. The O2 outlet of the CO2 electrolysis device is connected with the oxygen inlet of the heating furnace. The pressure swing adsorption device is provided with an H2 outlet and a CO outlet. The H2 outlet of the pressure swing adsorption device is connected with the inlet of the gas mixing device, the outlet of the gas mixing device is connected with the inlet of the third compressor, the outlet of the third compressor is connected with the inlet of the methanol synthesis device, and the methanol outlet of the methanol synthesis device is connected with the methanol inlet of the acetic acid synthesis device. The CO outlet of the pressure swing adsorption device is connected with two branches, one branch is connected with the inlet of the gas mixing device, and the other branch is connected with the CO inlet of the acetic acid synthesis device through the fourth compressor, and flow control valves are arranged on the two branches. The heat generated by the heating furnace is used as the heat source of the methanol synthesis device.

[0015] Figure 1 The purification device of the production system for co-production of blast furnace gas and acetic acid comprises a dust remover and a desulfurization tower, preferably one electric dust remover and two desulfurization towers. The CO2 separation and purification device adopts an organic amine circulation absorption device or a pressure swing adsorption device, and the organic amine circulation absorption device is preferred.

[0016] Figure 1 The production process of the production system for co-production of blast furnace gas and acetic acid is as follows. First, the blast furnace gas is subjected to dust removal by the electric dust remover of the purification device and desulfurization by the desulfurization tower, so that the total sulfur content of the gas is less than 1 ppm (V). Then, the purified blast furnace gas is used as fuel gas of the heating furnace to heat the CO and H2 mixed raw gas and provide the required heat for the methanol synthesis reaction. Oxygen produced by the CO2 electrolysis device is injected into the heating furnace to make the blast furnace gas burn more completely. The flue gas (composed of CO2 and N2) produced by the combustion is pressurized to 0.5 MPa by the first compressor and then transported to the CO2 separation and purification device to separate and purify CO2. The N2-rich adsorption tail gas is released.

[0017] The purified CO2 enters a CO2 electrolysis device, and CO2 and H2O are converted into synthesis gas by electro-catalytic technology in the CO2 electrolysis device, the composition of the synthesis gas satisfies CO:H2=1:1; then the synthesis gas is pressurized to 2.5 MPa by a second compressor and enters a pressure swing adsorption device for separation and purification, 99.5 vol% H2 and 99 vol% CO are obtained, wherein the H2 and part of the CO are transported to a gas mixing device for full mixing, and a methanol synthesis raw gas with a H / C molar ratio of 2-2.05 is obtained; the methanol synthesis raw gas is pressurized to 4-6 MPa by a third compressor, heated to 240-270 DEG C, and reacted in a methanol synthesis device to obtain methanol.

[0018] The methanol output from the methanol synthesis device directly enters an acetic acid synthesis device without condensation, and the remaining CO is pressurized to 2.5-3.0 MPa by a fourth compressor and then enters the acetic acid synthesis device, and the methanol directly reacts with CO in the acetic acid synthesis device to obtain acetic acid.

[0019] In order to control the H / C ratio of the raw gas in the gas mixing device to be 2-2.05 and meet the raw material demand of CO in the acetic acid synthesis device, a flow control valve is installed in the CO input pipeline of the gas mixing device and the fourth compressor respectively, which can be adjusted in production.

Claims

1. A production system for co-producing acetic acid from blast furnace gas, characterized in that: The system includes a purification unit, a heating furnace, a CO2 separation and purification unit, a CO2 electrolysis unit, a pressure swing adsorption (PSA) unit, a gas mixing unit, a methanol synthesis unit, and an acetic acid synthesis unit. The inlet of the purification unit is connected to the blast furnace gas pipeline, and the outlet is connected to the fuel inlet of the heating furnace. The flue gas outlet of the heating furnace is sequentially connected to the CO2 separation and purification unit and the CO2 electrolysis unit. The synthesis gas outlet of the CO2 electrolysis unit is connected to the inlet of the PSA unit, and the H2 outlet of the PSA unit is sequentially connected to the gas mixing unit, the methanol synthesis unit, and the acetic acid synthesis unit. The CO outlet of the PSA unit is connected to both the gas mixing unit and the acetic acid synthesis unit.

2. The acetic acid co-production system based on blast furnace gas according to claim 1, characterized in that: The O2 outlet of the CO2 electrolysis device is connected to the oxygen inlet of the heating furnace.

3. The acetic acid co-production system based on blast furnace gas according to claim 1, characterized in that: A compressor is installed on the pipeline between the heating furnace and the CO2 separation and purification device.

4. The acetic acid co-production system based on blast furnace gas according to claim 1, characterized in that: A second compressor is installed on the pipeline between the CO2 electrolysis device and the pressure swing adsorption device.

5. A production system for co-producing acetic acid from blast furnace gas according to claim 1, characterized in that: A compressor No. 3 is installed on the pipeline between the gas mixing unit and the methanol synthesis unit.

6. A blast furnace gas co-production system for acetic acid according to any one of claims 1-5, characterized in that: A compressor No. 4 is installed on the pipeline between the pressure swing adsorption device and the acetic acid synthesis device.

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