Tail gas treatment system of dimethyl sulfoxide production system

Abstract

A tail gas treatment system of a dimethyl sulfoxide production system comprises a buffer tank and further comprises a heating furnace, an absorption tank, a heat exchanger and a water-containing sulfoxide groove, a tank bottom feeding port of the absorption tank is connected with an emptying port of a thinner groove, a tank top exhaust port of the absorption tank is connected with a second inlet of the buffer tank, an inlet of the water-containing sulfoxide groove is connected with a tank bottom discharging port of the absorption tank, and the heating furnace is connected with the heat exchanger. An outlet of the water-containing sulfoxide tank is connected with an absorption liquid inlet of the absorption tank through a process medium channel of the heat exchanger, an infusion pump is arranged between the water-containing sulfoxide tank and the heat exchanger, an inlet of the heating furnace is connected with the buffer tank, an outlet of the heating furnace is emptied outwards, and a fan is arranged between the heating furnace and the buffer tank. The tail gas treatment device is simple in structure, low in operation cost and capable of stably treating tail gas generated in the dimethyl sulfoxide production process for a long time, and meets the environmental protection requirement.

Description

Technical Field

[0001] The utility model relates to the field of chemical industry, in particular to a tail gas treatment system of a dimethyl sulfoxide production system. Background Art

[0002] In the process of producing dimethyl sulfoxide in a chemical enterprise, the tail gas of the oxidation tower is treated by the absorption tower 101 and then discharged to the outside through the buffer tank 102, the crude sulfoxide is separated from most of the dimethyl sulfoxide and water by the continuous evaporator 103, and the liquid phase is sent to the vertical kettle 104 for negative pressure rectification, the non-condensable gas therein is discharged to the outside through the buffer tank 102, and the liquid phase is sent to the diluent tank 105, and the tail gas of the diluent tank is discharged to the outside through the buffer tank 102. Figure 1 shown.

[0003] This system has the following drawbacks:

[0004] 1. After the tail gas from the oxidation tower is treated by the absorption tower, the discharged tail gas still contains a small amount of sulfide;

[0005] 2. The temperature in the thinner tank is relatively high, and the tail gas contains a large amount of water vapor and a small amount of sulfide. If it is directly sent to the buffer tank, it is easy to cause serious corrosion and affect the service life of the supporting equipment;

[0006] 3. There is a strong odor on site.

[0007] Therefore, how to design a tail gas treatment system for a dimethyl sulfoxide production system that has a simple structure, a long operating cycle, and can effectively meet environmental protection requirements is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0008] The utility model aims to provide a tail gas treatment system for a dimethyl sulfoxide production system in view of the deficiencies in the prior art. The system has a simple structure and low operating cost, can stably treat the tail gas generated in the dimethyl sulfoxide production process for a long time, and meets environmental protection requirements.

[0009] The technical scheme of the utility model is: a tail gas treatment system of a dimethyl sulfoxide production system, comprising a buffer tank, wherein the buffer tank is provided with a first inlet for connecting with an exhaust port of an absorption tower, a second inlet for connecting with a venting port of a thinning material tank, and a third inlet for connecting with a non-condensable gas outlet of a vertical kettle tower top condenser, and further comprising a heating furnace, an absorption tank, a heat exchanger, and an aqueous sulfoxide tank, wherein a tank bottom feed port of the absorption tank is connected with a venting port of the thinning material tank, a tank top venting port of the absorption tank is connected with a second inlet of the buffer tank, an inlet of the aqueous sulfoxide tank is connected with a tank bottom discharge port of the absorption tank, an outlet of the aqueous sulfoxide tank is connected with an absorption liquid inlet of the absorption tank via a process medium channel of the heat exchanger, an infusion pump is provided between the aqueous sulfoxide tank and the heat exchanger, an inlet of the heating furnace is connected with the buffer tank, and an outlet is emptied to the outside, and a fan is provided between the heating furnace and the buffer tank.

[0010] A vacuum pump and a gas-liquid separator are arranged between the third inlet and the non-condensable gas outlet of the vertical kettle tower top condenser. The gas phase outlet of the gas-liquid separator is connected to the third inlet via the vacuum pump, and the liquid phase outlet of the gas-liquid separator supplies the dehydration system.

[0011] The aqueous sulfoxide tank is provided with a water replenishment port which is connected to the liquid phase outlet of the gas-liquid separator.

[0012] The aqueous sulfoxide tank supplies material to the diluent tank through a first pipeline.

[0013] The above technical solution has the following beneficial effects:

[0014] 1. The tail gas treatment system of the dimethyl sulfoxide production system includes a buffer tank, which is provided with a first inlet for connecting to the exhaust port of the absorption tower, a second inlet for connecting to the venting port of the diluent tank, and a third inlet for connecting to the non-condensable gas outlet of the vertical kettle tower top condenser, that is, the tail gas generated in each process of the dimethyl sulfoxide production process is sent to the buffer tank for buffering and flow stabilization. It also includes a heating furnace, an absorption tank, a heat exchanger, and an aqueous sulfoxide tank. The feed port at the bottom of the absorption tank is connected to the venting port of the thinning tank, the exhaust port at the top of the absorption tank is connected to the second inlet of the buffer tank, the inlet of the aqueous sulfoxide tank is connected to the discharge port at the bottom of the absorption tank, the outlet of the aqueous sulfoxide tank is connected to the absorption liquid inlet of the absorption tank through the process medium channel of the heat exchanger, and an infusion pump is arranged between the aqueous sulfoxide tank and the heat exchanger, that is, the high-temperature tail gas (a large amount of water vapor, gaseous sulfide, and a small amount of sulfoxide vapor) generated in the thinning tank enters the absorption tank, is sprayed and absorbed by the absorption liquid, so that most of the water vapor, gaseous sulfide, and sulfoxide vapor are transferred to the absorption liquid, and after being cooled by the heat exchanger, it is reused to ensure the absorption efficiency and absorption rate of the absorption liquid for water vapor, gaseous sulfide, and sulfoxide vapor. The vented tail gas after absorption treatment is sent to the buffer tank, which is mild and has low sulfide content, sulfoxide vapor content, and moisture content, effectively reducing the corrosion intensity of the buffer tank and downstream process equipment. The inlet of the heating furnace is connected to the buffer tank and the outlet is emptied to the outside. A fan is arranged between the heating furnace and the buffer tank. The buffered and warmed tail gas is sent to the heating furnace and incinerated to reduce the online sulfur dioxide content, thus meeting environmental protection requirements.

[0015] 2. A vacuum pump and a gas-liquid separator are arranged between the third inlet and the non-condensable gas outlet of the vertical kettle top condenser. The gas phase outlet of the gas-liquid separator is connected to the third inlet via the vacuum pump, and the liquid phase outlet of the gas-liquid separator supplies the dehydration system. The gas phase discharged from the vertical kettle is separated by the gas-liquid separator, and the gas phase sulfide and sulfoxide vapor mixed therein are separated into liquid phase and transported to the dehydration system for separation and purification, thereby reducing the content of sulfide and sulfoxide vapor in the tail gas discharged to the buffer tank, improving the sulfoxide yield, and meeting environmental protection requirements.

[0016] 3. The aqueous sulfoxide tank is provided with a water replenishment port, which is connected to the liquid phase outlet of the gas-liquid separator. The aqueous sulfoxide tank supplies the diluent tank through the first pipeline, and the absorption liquid can be replenished to the aqueous sulfoxide tank through the gas-liquid separator, and the absorption rich liquid is sent to the diluent tank for downstream process treatment to achieve closed-loop treatment.

[0017] Further description is given below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of an exhaust gas treatment system in the background technology;

[0019] Figure 2 It is a connection diagram of the utility model.

[0020] In the accompanying drawings, 1 is a buffer tank, 11 is a first inlet, 12 is a second inlet, 13 is a third inlet, 2 is a heating furnace, 3 is an absorption tank, 4 is a heat exchanger, 5 is an aqueous sulfoxide tank, 6 is an infusion pump, 7 is a fan, 8 is a vacuum pump, 9 is a gas-liquid separator, 10 is a water supply port, and a is a first pipeline. DETAILED DESCRIPTION

[0021] See also Figure 2, is a specific embodiment of an exhaust gas treatment system of a dimethyl sulfoxide production system. The exhaust gas treatment system of the dimethyl sulfoxide production system includes a buffer tank 1, the buffer tank 1 is provided with a first inlet 11 for connecting to the exhaust port of the oxidation tower absorption tower, a second inlet 12 for connecting to the venting port of the thinner tank, and a third inlet 13 for connecting to the non-condensable gas outlet of the vertical kettle top condenser. In this embodiment, a vacuum pump 8 and a gas-liquid separator 9 are provided between the third inlet 13 and the non-condensable gas outlet of the vertical kettle top condenser. The gas phase outlet of the gas-liquid separator 9 is connected to the third inlet 13 via the vacuum pump 8, and the liquid phase outlet of the gas-liquid separator 9 supplies the dehydration system. It also includes a heating furnace 2, an absorption tank 3, a heat exchanger 4, and a water-containing sulfoxide tank 5. The feed port at the bottom of the absorption tank 3 is connected to the venting port of the thinner tank, and the exhaust port at the top of the absorption tank 3 is connected to the second inlet 12 of the buffer tank. The inlet of the aqueous sulfoxide tank 5 is connected to the bottom discharge port of the absorption tank. Obviously, the bottom feed port of the absorption tank is higher than the bottom discharge port of the absorption tank. Correspondingly, the bottom feed port feeds gaseous materials, and the bottom discharge port discharges liquid materials. The outlet of the aqueous sulfoxide tank 5 is connected to the absorption liquid inlet of the absorption tank through the process medium channel of the heat exchanger 4. Usually, a water distributor is provided on the top of the absorption tank, which is connected to the absorption liquid inlet of the absorption tank. In this embodiment, the aqueous sulfoxide tank 5 is provided with a water replenishment port 10, which is connected to the liquid phase outlet of the gas-liquid separator 9, and the aqueous sulfoxide tank 5 supplies the diluent tank through the first pipeline a. Obviously, valves are provided on the water replenishment port and the first pipeline. An infusion pump 6 is provided between the aqueous sulfoxide tank 5 and the heat exchanger 4. The inlet of the heating furnace 2 is connected to the buffer tank 1, and the outlet is emptied to the outside. Usually, it is connected to the chimney for external evacuation. A fan 7 is provided between the heating furnace 2 and the buffer tank 1.

[0022] The working principle of the utility model is as follows: the tail gas discharged from the oxidation tower of the dimethyl sulfoxide production system is absorbed and treated by the absorption tower, and then sent to the buffer tank through the first inlet. The crude sulfoxide obtained by the oxidation tower is sent to the continuous evaporator, and the bottom temperature is controlled to be 145-158°C. A large amount of water and dimethyl sulfoxide are evaporated and enter the dehydration system. A small part of water, dimethyl sulfoxide and a large amount of nitrate enter the vertical kettle (intermittent stirring kettle), and the temperature is controlled to be below 160°C. The salt concentrated in the vertical kettle enters the diluent tank for temporary storage. The gas phase discharged from the vertical kettle is condensed by the top condenser, separated by the gas-liquid separator, and sent to the buffer tank by the vacuum pump. The tail gas generated in the diluent tank enters the absorption tank, and after being absorbed by the absorption liquid, it is sent to the buffer tank, wherein the absorption liquid of the absorption tank is the liquid phase discharged by the gas-liquid separator, and the absorption rich liquid is sent to the water-containing sulfoxide tank, and the temperature is reduced to below 50°C as the absorption liquid for recycling. The tail gas collected in the buffer tank is sent to the heating furnace, and after being burned at 135°C, it enters the chimney for emptying.

[0023] The applicant has verified that by adopting the tail gas treatment system of the utility model, the online sulfur dioxide in the chimney is reduced from 330-350 mg / L to 180-220 mg / L, and the odor on site is eliminated.

Claims

1. A tail gas treatment system for a dimethyl sulfoxide production system, comprising a buffer tank (1), wherein the buffer tank (1) is provided with a first inlet (11) for connecting to an exhaust port of an oxidation tower and an absorption tower, a second inlet (12) for connecting to a vent port of a diluent tank, and a third inlet (13) for connecting to a non-condensable gas outlet of a vertical kettle tower top condenser, characterized in that: It also includes a heating furnace (2), an absorption tank (3), a heat exchanger (4), and an aqueous sulfoxide tank (5). The feed port at the bottom of the absorption tank (3) is connected to the venting port of the thinner tank, and the exhaust port at the top of the absorption tank (3) is connected to the second inlet (12) of the buffer tank. The inlet of the aqueous sulfoxide tank (5) is connected to the tank bottom discharge port of the absorption tank, the outlet of the aqueous sulfoxide tank (5) is connected to the absorption liquid inlet of the absorption tank through the process medium channel of the heat exchanger (4), and an infusion pump (6) is arranged between the aqueous sulfoxide tank (5) and the heat exchanger (4). The inlet of the heating furnace (2) is connected to the buffer tank (1), and the outlet is emptied to the outside. A fan (7) is arranged between the heating furnace (2) and the buffer tank (1).

2. The tail gas treatment system of the dimethyl sulfoxide production system according to claim 1, characterized in that: A vacuum pump (8) and a gas-liquid separator (9) are provided between the third inlet (13) and the non-condensable gas outlet of the vertical kettle tower top condenser. The gas phase outlet of the gas-liquid separator (9) is connected to the third inlet (13) via the vacuum pump (8), and the liquid phase outlet of the gas-liquid separator (9) supplies the dehydration system.

3. The tail gas treatment system of the dimethyl sulfoxide production system according to claim 2, characterized in that: The aqueous sulfoxide tank (5) is provided with a water replenishment port (10) which is connected to the liquid phase outlet of the gas-liquid separator (9).

4. The tail gas treatment system of the dimethyl sulfoxide production system according to claim 1, characterized in that: The aqueous sulfoxide tank (5) supplies material to the diluent tank via the first pipeline (a).

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