Hydrogen sulfide recovery device

Abstract

The utility model relates to a hydrogen sulfide recovery device, which comprises a compressor and a hydrogen sulfide recovery device, the water cooler is used for cooling the feed gas and cooling the feed gas and is connected with a gas output port of the compressor through a pipeline; the heat exchanger is used for further cooling the feed gas and is connected with the water cooler through a pipeline; the first rectifying tower is connected with the heat exchanger through a pipeline; the second rectifying tower is used for further rectifying the liquid phase discharged from the bottom of the first rectifying tower and connected with the first rectifying tower through a first pipeline, the top of the second rectifying tower is connected with a hydrogen sulfide discharge pipe, and a second reboiler at the bottom of the second rectifying tower is connected with a methanol discharge pipe. The hydrogen sulfide recovery device disclosed by the utility model can be used for separating and recovering discharged tail gas, is energy-saving and environment-friendly, and has higher economic value and social value.

Description

Technical Field

[0001] The utility model relates to a gas recovery device, in particular to a hydrogen sulfide recovery device. Background Art

[0002] In chemical production using coal as raw material, the crude synthesis gas contains a large amount of excess CO2, a small amount of H2S, COS and other acidic gases. These acidic gases are not conducive to production. The sulfides in them can cause catalyst poisoning in downstream production and must be removed and recovered.

[0003] Low-temperature methanol washing uses cold methanol as the absorption solvent and utilizes the excellent property of methanol's great solubility in acidic gases at low temperatures to remove acidic gases from the raw gas. The process generally includes using an absorption tower to absorb the acidic gases, using several analysis towers to analyze the acidic gases and returning the lean methanol to the absorption tower to achieve the purpose of recycling methanol. The gas produced by this process has a high degree of purification, and the desulfurization and decarbonization of the gas can be carried out in stages and selectively in the same tower. The low-temperature methanol washing process technology is mature and has a good application in industry. This technology is mostly used in large-scale synthetic ammonia plants in China that use coal and residual oil as raw materials.

[0004] After the crude synthesis gas is washed with low-temperature methanol, the corresponding tail gas will be discharged. One of the tail gases contains components such as carbon dioxide, hydrogen sulfide, methanol, etc., and needs to be purified. Utility Model Content

[0005] The utility model aims to provide a hydrogen sulfide recovery device suitable for tail gas treatment of a low-temperature methanol washing device.

[0006] The hydrogen sulfide recovery device of the utility model comprises:

[0007] A compressor for pressurizing the raw gas;

[0008] A water cooler used to cool the raw gas to lower its temperature is connected to the gas outlet of the compressor through a pipeline;

[0009] A heat exchanger for further cooling the raw gas, connected to the water cooler through a pipeline;

[0010] A first distillation tower for distilling the raw gas, connected to the heat exchanger through a pipeline;

[0011] The second distillation tower is used to further distill the liquid phase discharged from the bottom of the first distillation tower, and is connected to the first distillation tower through a first pipeline. The top of the second distillation tower is connected to a hydrogen sulfide discharge pipe, and the bottom reboiler of the second distillation tower is connected to a methanol discharge pipe.

[0012] The utility model discloses a hydrogen sulfide recovery device, wherein the top of the first distillation tower is connected to the first condenser and the first separator through the second pipeline, and the gas phase outlet of the first separator is connected to the carbon dioxide tail gas exhaust pipe, so that the gas phase at the top of the first distillation tower is condensed and cooled by the first condenser, and then enters the first separator to separate the gas phase and the liquid phase, and the liquid phase outlet of the first separator is connected to the top of the first distillation tower.

[0013] The utility model relates to a hydrogen sulfide recovery device, wherein the carbon dioxide tail gas discharge pipe passes through a heat exchanger, so that the carbon dioxide tail gas is discharged after being reheated by the heat exchanger.

[0014] The hydrogen sulfide recovery device of the utility model, wherein the top of the second distillation tower is connected to the second condenser and the second separator through the third pipeline, so that the gas phase at the top of the second distillation tower is condensed and cooled by the second condenser, and then enters the second separator to separate the gas phase and the liquid phase, the gas phase outlet of the second separator is connected to the hydrogen sulfide discharge pipe, and the liquid phase outlet of the second separator is connected to the top of the second distillation tower.

[0015] The hydrogen sulfide recovery device of the utility model, wherein the bottom reboiler of the first distillation tower is connected to the first hot material inlet pipe and the first hot material discharge pipe, the bottom reboiler of the second distillation tower is connected to the second hot material inlet pipe and the second hot material discharge pipe, and the bottom reboiler of the first distillation tower is connected to the second distillation tower through the first pipeline.

[0016] The hydrogen sulfide recovery device of the utility model can separate and recover the discharged tail gas, which is energy-saving and environmentally friendly and has great economic and social value. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the hydrogen sulfide recovery device of the utility model. DETAILED DESCRIPTION

[0018] like Figure 1 As shown, the hydrogen sulfide recovery device of the utility model comprises:

[0019] Compressor C1 for pressurizing the raw gas;

[0020] The water cooler E1 used to cool the raw gas to lower its temperature is connected to the gas outlet of the compressor through a pipeline;

[0021] The heat exchanger E2 used for further cooling the raw gas is connected to the water cooler through a pipeline;

[0022] The first distillation tower T1 for distilling the raw gas is connected to the heat exchanger through a pipeline;

[0023] The second distillation tower T2 for further distilling the liquid phase discharged from the bottom of the first distillation tower is connected to the first distillation tower through the first pipeline 10, the top of the second distillation tower is connected to the hydrogen sulfide discharge pipe 80, and the bottom reboiler of the second distillation tower is connected to the methanol discharge pipe 90.

[0024] The hydrogen sulfide recovery device of the utility model, wherein the top of the first distillation tower is connected to the first condenser E3 and the first separator V1 through the second pipeline 20, and the gas phase outlet of the first separator is connected to the carbon dioxide tail gas exhaust pipe 70, so that the gas phase at the top of the first distillation tower is condensed and cooled by the first condenser, and then enters the first separator to separate the gas phase and the liquid phase, and the liquid phase outlet of the first separator is connected to the top of the first distillation tower.

[0025] In the hydrogen sulfide recovery device of the utility model, the carbon dioxide tail gas discharge pipe 70 passes through the heat exchanger E2, so that the carbon dioxide tail gas is discharged after being reheated by the heat exchanger.

[0026] The hydrogen sulfide recovery device of the utility model, wherein the top of the second distillation tower is connected to the second condenser E5 and the second separator V2 through the third pipeline 30, so that the gas phase at the top of the second distillation tower is condensed and cooled by the second condenser, and then enters the second separator to separate the gas phase and the liquid phase, the gas phase outlet of the second separator is connected to the hydrogen sulfide discharge pipe, and the liquid phase outlet of the second separator is connected to the top of the second distillation tower.

[0027] The hydrogen sulfide recovery device of the utility model, wherein the bottom reboiler E4 of the first distillation tower is connected to the first hot material inlet pipe 21 and the first hot material discharge pipe 22, the bottom reboiler E6 of the second distillation tower is connected to the second hot material inlet pipe 23 and the second hot material discharge pipe 24, and the bottom reboiler of the first distillation tower is connected to the second distillation tower through the first pipeline.

[0028] The working process of the hydrogen sulfide recovery device of the utility model:

[0029] After the raw gas enters the compressor C1 for pressurization, it is cooled by the water cooler E1, and then cooled by the heat exchanger E2 before entering the first distillation tower T1. The gas phase at the top of the tower is condensed and cooled by the first condenser E3, and enters the first separator V1. The gas phase is discharged from the top, and after being reheated by the heat exchanger E2, the carbon dioxide tail gas is discharged. The liquid phase of the first separator V1 returns to the top of the first distillation tower. The liquid phase at the bottom of the tower is heated and evaporated by the bottom reboiler E4 of the first distillation tower, and the liquid phase is discharged from the bottom of the tower and enters the second distillation tower T2. The gas phase at the top of the tower is condensed and cooled by the second condenser E5, and enters the second separator V2. The hydrogen sulfide product is discharged from the top. The liquid phase of the second separator V2 returns to the top of the distillation tower. The liquid phase at the bottom of the tower is heated and evaporated by the bottom reboiler E6 of the second distillation tower, and the methanol product is discharged from the bottom of the tower.

[0030] The hot material enters the bottom reboiler E4 of the first distillation tower, and exits the bottom reboiler E4 of the first distillation tower after providing heat. The hot material enters the bottom reboiler E6 of the second distillation tower, and exits the bottom reboiler E6 of the second distillation tower after providing heat.

[0031] The heat exchanger may be a plate-fin heat exchanger, a plate heat exchanger, a coiled-tube heat exchanger, a shell-and-tube heat exchanger or a combination thereof.

[0032] Compressors can be turbine, screw, diaphragm or reciprocating.

[0033] The raw gas is any combination of hydrocarbon media such as H2S, CO2, methanol, nitrogen, and hydrogen.

[0034] The reboiler can be placed inside the distillation tower or outside the distillation tower.

[0035] The hydrogen sulfide recovery device of the utility model is particularly suitable for tail gas treatment of a low-temperature methanol washing device.

[0036] The hydrogen sulfide recovery device of the utility model can separate and recover the discharged tail gas, which is energy-saving and environmentally friendly and has great economic and social value.

[0037] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A hydrogen sulfide recovery device, characterized in that: include: A compressor for pressurizing the raw gas; A water cooler used to cool the raw gas to lower its temperature is connected to the gas outlet of the compressor through a pipeline; A heat exchanger for further cooling the raw gas, connected to the water cooler through a pipeline; A first distillation tower for distilling the raw gas, connected to the heat exchanger through a pipeline; The second distillation tower is used to further distill the liquid phase discharged from the bottom of the first distillation tower, and is connected to the first distillation tower through a first pipeline. The top of the second distillation tower is connected to a hydrogen sulfide discharge pipe, and the bottom reboiler of the second distillation tower is connected to a methanol discharge pipe.

2. The hydrogen sulfide recovery device according to claim 1, characterized in that: The top of the first distillation tower is connected to the first condenser and the first separator through the second pipeline, and the gas phase outlet of the first separator is connected to the carbon dioxide tail gas exhaust pipe, so that the gas phase at the top of the first distillation tower is condensed and cooled by the first condenser, and then enters the first separator to separate the gas phase and the liquid phase, and the liquid phase outlet of the first separator is connected to the top of the first distillation tower.

3. The hydrogen sulfide recovery device according to claim 2, characterized in that: The carbon dioxide tail gas exhaust pipe passes through a heat exchanger so that the carbon dioxide tail gas is discharged after being reheated by the heat exchanger.

4. The hydrogen sulfide recovery device according to claim 3, characterized in that: The top of the second distillation tower is connected to the second condenser and the second separator through the third pipeline, so that the gas phase at the top of the second distillation tower is condensed and cooled by the second condenser, and then enters the second separator to separate the gas phase and the liquid phase. The gas phase outlet of the second separator is connected to the hydrogen sulfide exhaust pipe, and the liquid phase outlet of the second separator is connected to the top of the second distillation tower.

5. The hydrogen sulfide recovery device according to claim 4, characterized in that: The bottom reboiler of the first distillation tower is connected to the first hot material inlet pipe and the first hot material outlet pipe, the bottom reboiler of the second distillation tower is connected to the second hot material inlet pipe and the second hot material outlet pipe, and the bottom reboiler of the first distillation tower is connected to the second distillation tower through the first pipeline.

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