Gas inlet temperature control system of waste gas fine desulfurization tower

Abstract

The utility model discloses a waste gas fine desulfurization tower inlet gas temperature control system which comprises a control end, a pressure reduction pipeline, a buffer tank a, a pressure release line, a heat exchanger a and a pretreatment tail gas main pipeline used for conveying low-pressure pretreatment tail gas output by a hydrolysis tower, the pretreatment tail gas pressure reduction pipeline is fed into the buffer tank a, and the buffer tank a is communicated with the heat exchanger a through the pressure release line. And an exhaust gas turbocharger is arranged on the pressure release line. According to the waste gas fine desulfurization tower inlet gas temperature control system, the waste gas turbocharger is additionally arranged, pretreated tail gas is divided into two components to be conveyed, one component is normally cooled, the other component pressurizes tail gas in the high-pressure cooling pipeline through the waste gas turbocharger, the pressure release line serves as a power source, the part of tail gas is compressed and then subjected to heat exchange, and the tail gas in the high-pressure cooling pipeline is subjected to heat exchange; and mixing with the two groups of tail gas subjected to heat exchange according to a certain proportion to reach a target temperature, entering a buffer tank b, stabilizing, and outputting, so that the temperature is controllable.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of fine desulfurization equipment technical field, specifically a kind of waste gas fine desulfurization tower air intake temperature control system. BACKGROUND

[0002] Fine desulfurization tower is used for the gas that is subjected to preliminary desulfurization treatment to carry out deep desulfurization equipment, dry method fine desulfurization: utilize desulfurizer and sulfide in gas to carry out chemical reaction or adsorption, sulfide is converted into solid or liquid material, to reach the purpose of desulfurization, such as in coke oven gas fine desulfurization, through catalytic oxidation reaction absorption hydrogen sulfide in coal gas, the substance generated by reaction is adsorbed and deposited in filler, wet method fine desulfurization: it is usually to utilize specific solvent and sulfide in gas to carry out chemical reaction, generate soluble sulfide or thiosulfate etc., then through regeneration process, sulfide in solvent is removed, so that solvent can be recycled.

[0003] Hydrolysis desulfurization tower is converted into H2S under the action of hydrolysis desulfurizer COS, and then enters fine desulfurization tower after being cooled to normal temperature by desulfurization water cooler, water cooler is usually heat exchanger, passes through cold medium and tail gas heat exchange, takes away the heat of tail gas, so that it is reduced to normal temperature, then enters fine desulfurization tower, the cooling efficiency of water cooler is influenced by many factors, so that tail gas temperature is unstable, influences the desulfurization effect of fine desulfurization tower, in order to better and more stable control tail gas cooling temperature, guarantee the desulfurization effect of fine desulfurization tower, the present application is proposed. CONTENT OF UTILITY MODEL

[0004] The utility model aims at providing a kind of waste gas fine desulfurization tower air intake temperature control system to solve the problems raised in the above background.

[0005] To achieve the above object, the utility model provides the following technical scheme:

[0006] Waste gas fine desulfurization tower air intake temperature control system, including control end, pressure reducing pipeline, buffer tank a, pressure release line, heat exchanger a and for conveying the low-pressure pretreatment tail gas of hydrolysis tower output pretreatment tail gas main pipeline, the pretreatment tail gas pressure reducing pipeline is sent into buffer tank a, buffer tank a is communicated with heat exchanger a by pressure release line, waste gas turbocharger is set on the pressure release line, pretreatment tail gas main pipeline is communicated high-pressure cooling pipeline and low-pressure cooling pipeline by temperature control valve, waste gas turbocharger is pressurized to tail gas in high-pressure cooling pipeline by high-pressure tail gas in pressure release line as power source, high-pressure cooling pipeline and low-pressure cooling pipeline are respectively provided with heat exchanger b and heat exchanger c, and the tail gas output end of heat exchanger b and heat exchanger c is passed through ejector, and the output end of ejector is provided buffer tank b.

[0007] As a further scheme of the present application: the heat exchanger a, the heat exchanger b and the heat exchanger c are all provided with cooling water circulating pipelines, and the heat exchanger a, the heat exchanger b and the heat exchanger c are all pipe heat exchangers.

[0008] As a further scheme of the present application: the tail gas output ends of the heat exchanger b and the heat exchanger c are respectively communicated with the ejector through low-pressure tail gas pipelines and high-pressure tail gas pipelines.

[0009] As a further scheme of the present application: the ejector is composed of a working fluid inlet pipe, a receiving chamber, an ejecting fluid inlet pipe, a mixing chamber and a diffuser;

[0010] The receiving chamber is respectively communicated with the working fluid inlet pipe, the ejecting fluid inlet pipe and the mixing chamber, the mixing chamber is communicated with the diffuser, high-speed fluid flows in through the working fluid inlet pipe, low-speed fluid flows in through the ejecting fluid inlet pipe, and the high-speed fluid and the low-speed fluid are mixed in the mixing chamber and discharged from the diffuser.

[0011] As a further scheme of the present application: the low-pressure tail gas pipelines and the high-pressure tail gas pipelines are respectively provided with sensor groups and gas valves, the sensor groups include temperature sensors and pressure sensors, the sensor groups and the gas valves are respectively electrically connected with a control end, and the control end controls the opening degree of the gas valves through the tail gas temperature detected by the sensor groups.

[0012] As a further scheme of the present application: a direct discharge pipeline is further arranged on the pressure release line, a booster line is arranged on the high-pressure cooling pipeline, and an air pressure pump for increasing the gas pressure is installed on the booster line.

[0013] As a further scheme of the present application: valves for controlling the pipelines are respectively installed on the direct discharge pipeline and the booster line, and the valve arranged on the direct discharge pipeline is a pressure relief valve.

[0014] Compared with the prior art, the present application has the following beneficial effects:

[0015] The exhaust gas fine desulfurization tower inlet temperature control system adds an exhaust gas turbocharger, divides the pretreated tail gas into two groups for conveying, normally cools one group, and boosts the tail gas in the high-pressure cooling pipeline through the exhaust gas turbocharger, the pressure release line serves as a power source, compresses the part of the tail gas, exchanges heat, mixes with the two groups of tail gas after heat exchange at a certain ratio, reaches the target temperature, enters the buffer tank b after stabilization, and is output, so that the temperature is controllable. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is an embodiment one structural schematic view of an exhaust gas fine desulfurization tower inlet temperature control system.

[0017] Figure 2This is a schematic diagram of the structure of an embodiment two of a waste gas desulfurization tower inlet temperature control system;

[0018] In the diagram: 1. Pressure reducing line; 2. Buffer tank a; 3. Pressure relief line; 4. Heat exchanger a; 5. Exhaust gas turbocharger; 6. Boost line; 7. Pre-treatment exhaust gas main line; 8. High-pressure exhaust gas line; 9. Low-pressure cooling line; 10. Low-pressure exhaust gas line; 11. Heat exchanger b; 12. Ejector; 13. Buffer tank b; 14. Sensor group; 15. High-pressure cooling line; 16. Heat exchanger c; 17. Straight discharge line. Detailed Implementation

[0019] Example 1

[0020] Please see Figure 1 In this embodiment of the invention, the inlet temperature control system for the waste gas desulfurization tower includes a control terminal, a pressure reducing pipeline 1, a buffer tank a2, a pressure relief line 3, a heat exchanger a4, and a pre-treated tail gas main pipeline 7 for conveying the low-pressure pre-treated tail gas output from the hydrolysis tower. The pre-treated tail gas pressure reducing pipeline 1 sends the gas into the buffer tank a2. The buffer tank a2 is connected to the heat exchanger a4 via the pressure relief line 3. An waste gas turbocharger 5 is installed on the pressure relief line 3. The pre-treated tail gas main pipeline 7 is connected to the heat exchanger a4 via a temperature control valve. The high-pressure cooling pipeline 15 and the low-pressure cooling pipeline 9 are connected. The exhaust gas turbocharger 5 uses the high-pressure exhaust gas in the pressure relief line 3 as a power source to pressurize the exhaust gas in the high-pressure cooling pipeline 15. Heat exchangers b11 and c16 are respectively installed on the high-pressure cooling pipeline 15 and the low-pressure cooling pipeline 9. The exhaust gas output ends of heat exchangers b11 and c16 are connected to ejectors 12. A buffer tank b13 is installed at the output end of ejectors 12. According to Chinese Patent No. 2025204 Application 682145 proposes a hydrodesulfurization tower for industrial waste gas treatment. This application requires depressurization of the exhaust gas. During hydrolysis, the exhaust gas is compressed to a pressure above 0.9 MPa by a compressor in its first and second stages, which can then drive an exhaust gas turbocharger 5. During depressurization, the exhaust gas turbocharger 5 drives the low-pressure exhaust gas in the high-pressure cooling pipeline 15 to undergo secondary compression, making it higher in pressure than the exhaust gas in the low-pressure cooling pipeline 9. After heat exchange in heat exchangers b11 and c16, the gas is then mixed again by an ejector 12, releasing the pressure. The high-pressure exhaust gas, after heat exchange, experiences further temperature reduction, resulting in a lower temperature compared to the exhaust gas output from the low-pressure cooling pipeline 9. Furthermore, the temperature in the later stages of mixing is lower than that of water-cooled systems in existing technologies. The pressure difference during the high-pressure exhaust gas depressurization process is utilized as kinetic energy, saving energy and further reducing the cooling rate and temperature.

[0021] In a preferred embodiment, heat exchangers a4, b11 and c16 are all equipped with cooling water circulation pipelines. Heat exchangers a4, b11 and c16 are all tubular heat exchangers. The cooling water circulation pipelines come from the evaporation tower and are transported to each heat exchanger for heat exchange by a circulation pump.

[0022] In a preferred embodiment, the exhaust gas output ends of heat exchanger b11 and heat exchanger c16 are connected to ejector 12 via low-pressure exhaust gas pipeline 10 and high-pressure exhaust gas pipeline 8, respectively. Ejector 12 consists of a working fluid inlet pipe, a receiving chamber, an ejector fluid inlet pipe, a mixing chamber, and a diffuser.

[0023] The receiving chamber is connected to the working fluid inlet pipe, the ejector fluid inlet pipe, and the mixing chamber. The mixing chamber is connected to the diffuser. High-speed fluid flows in through the working fluid inlet pipe, and low-speed fluid flows in through the ejector fluid inlet pipe. They mix in the mixing chamber and are discharged from the diffuser. The ejector 12 is a device that uses high-pressure fluid to eject low-pressure fluid, thus mixing the two. The high-pressure working fluid is ejected at high speed through the nozzle, forming a high-speed jet at the nozzle outlet. According to Bernoulli's principle, the high-speed jet creates a low-pressure zone in the surrounding area. The low-pressure ejected fluid is drawn into the ejector under the action of the pressure difference and mixes with the high-speed working fluid in the mixing chamber. The mixed fluid decelerates in the diffuser pipe, achieving the mixing effect.

[0024] In a preferred embodiment, a sensor group 14 and a valve are respectively installed on the low-pressure exhaust gas pipeline 10 and the high-pressure exhaust gas pipeline 8. The sensor group 14 includes a temperature sensor and a pressure sensor. The sensor group 14 and the valve are respectively connected to the control terminal by electrical signals. The control terminal controls the opening degree of the valve by the exhaust gas temperature detected by the sensor group 14. The control terminal is existing technology and can be a DCS system or an independent computer system. The sensor group 14 detects that the two are mixed in a certain proportion so that the temperature reaches the target temperature after the pressure is balanced. By adjusting the proportion, the temperature after the pressure is released can be adjusted to achieve the purpose of temperature control.

[0025] Example 2

[0026] Please see Figure 2In this embodiment of the invention, the exhaust gas desulfurization tower inlet temperature control system includes a direct discharge pipeline 17 on the pressure release line 3 and a booster line 6 on the high-pressure cooling pipeline 15. An air compressor pump for increasing the exhaust gas pressure is installed on the booster line 6. Valves for controlling the pipelines are installed on both the direct discharge pipeline 17 and the booster line 6. The valve on the direct discharge pipeline 17 is a pressure relief valve. Since the exhaust gas pressure on the pressure release line 3 is unstable, when the pressure cannot meet the operating requirements of the exhaust gas turbocharger 5... By controlling the valve, the pressure relief line 3 is switched to the direct discharge line 17. The direct discharge line 17 is connected in parallel with the exhaust gas turbocharger 5, and the exhaust gas directly enters the heat exchanger a4. At this time, the exhaust gas in the high-pressure cooling line 15 cannot be compressed. Therefore, by switching the pipeline, the exhaust gas is sent to the booster line 6. The booster line 6 is connected in parallel with the exhaust gas turbocharger 5. The exhaust gas is boosted by the air compressor, and its temperature is controlled so that it can still maintain a relatively stable exhaust gas cooling effect when the exhaust gas pressure is insufficient or unstable.

[0027] It should be noted that all the above embodiments belong to the same utility model concept, and the descriptions of each embodiment have different focuses. Where the description in a particular embodiment is not detailed, please refer to the description in other embodiments.

[0028] The embodiments described above merely illustrate the implementation of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A waste gas desulfurization tower inlet temperature control system, comprising a control terminal, a pressure reducing pipeline (1), a buffer tank a (2), a pressure relief line (3), a heat exchanger a (4), and a pre-treated tail gas main pipeline (7) for conveying the low-pressure pre-treated tail gas output from the hydrolysis tower, wherein the pressure reducing pipeline (1) is fed into the buffer tank a (2), and the buffer tank a (2) is connected to the heat exchanger a (4) through the pressure relief line (3), characterized in that, The pressure relief line (3) is equipped with an exhaust gas turbocharger (5). The pre-treatment exhaust gas main pipeline (7) is connected to the high-pressure cooling pipeline (15) and the low-pressure cooling pipeline (9) through a temperature control valve. The exhaust gas turbocharger (5) uses the high-pressure exhaust gas in the pressure relief line (3) as a power source to pressurize the exhaust gas in the high-pressure cooling pipeline (15). The high-pressure cooling pipeline (15) and the low-pressure cooling pipeline (9) are respectively equipped with heat exchangers b (11) and c (16). The exhaust gas output ends of heat exchangers b (11) and c (16) are connected to ejectors (12). The output end of ejectors (12) is equipped with a buffer tank b (13).

2. The inlet temperature control system for the waste gas desulfurization tower according to claim 1, characterized in that, The heat exchangers a (4), b (11) and c (16) are all equipped with cooling water circulation pipelines, and all three are tubular heat exchangers.

3. The inlet temperature control system for the waste gas desulfurization tower according to claim 1, characterized in that, The exhaust gas output ends of heat exchanger b (11) and heat exchanger c (16) are connected to ejector (12) through low-pressure exhaust gas pipeline (10) and high-pressure exhaust gas pipeline (8), respectively.

4. The inlet temperature control system for the waste gas desulfurization tower according to claim 3, characterized in that, The ejector (12) consists of a working fluid inlet pipe, a receiving chamber, an ejector fluid inlet pipe, a mixing chamber, and a diffuser; The receiving chamber is connected to the working fluid inlet pipe, the ejector fluid inlet pipe, and the mixing chamber. The mixing chamber is connected to the diffuser. High-speed fluid flows in through the working fluid inlet pipe, and low-speed fluid flows in through the ejector fluid inlet pipe. They mix in the mixing chamber and are then discharged from the diffuser.

5. The inlet temperature control system for the waste gas desulfurization tower according to claim 3, characterized in that, Sensor groups (14) and valves are respectively installed on the low-pressure exhaust gas pipeline (10) and the high-pressure exhaust gas pipeline (8). The sensor group (14) includes a temperature sensor and a pressure sensor. The sensor group (14) and the valve are respectively connected to the control terminal by electrical signal. The control terminal controls the opening degree of the valve by the exhaust gas temperature detected by the sensor group (14).

6. The waste gas desulfurization tower inlet temperature control system according to any one of claims 1-5, characterized in that, The pressure relief line (3) is also equipped with a straight discharge line (17), and the high-pressure cooling line (15) is equipped with a booster line (6). An air compressor is installed on the booster line (6) to increase the exhaust gas pressure.

7. The inlet temperature control system for the waste gas desulfurization tower according to claim 6, characterized in that, The straight discharge pipeline (17) and the booster line (6) are respectively equipped with valves for controlling the pipeline, and the valve installed on the straight discharge pipeline (17) is a pressure relief valve.

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