Supergravity purification system for high-concentration hydrogen sulfide waste gas

Abstract

The utility model belongs to the technical field of hydrogen sulfide waste gas purification, and particularly relates to a supergravity purification system for high-concentration hydrogen sulfide waste gas, which comprises an asphalt modification tower, a lye tank, a combustion furnace and a supergravity machine, the liquid outlet end of the lye tank is connected with the liquid inlet end of the supergravity machine, and the gas outlet end of the supergravity machine is connected with the gas inlet end of the combustion furnace. According to the utility model, the supergravity machine is additionally arranged, so that the contact surface area of waste gas and liquid is increased, the mass transfer coefficient and the reaction rate are effectively improved, and H2S and part of organic matters in non-condensable gas can be favorably eluted by alkali liquor, so that the content of sulfur in tail gas generated after the non-condensable gas is combusted is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of hydrogen sulfide waste gas purification, and specifically relates to a supergravity purification system for high-concentration hydrogen sulfide waste gas. Background Art

[0002] The non-condensable gas produced by the asphalt modification tower is collected in the tail gas combustion furnace of the tank area for combustion, and the generated gas will enter the desulfurization tower for desulfurization to meet environmental standards.

[0003] However, the H2S content in the non-condensable gas produced by the asphalt reformer is relatively high, with the highest concentration reaching 15000-20000 mg / Nm 3 The exhaust gas flow rate is about 600-1200m3 / h. The SO2 content in the gas after combustion is too high, resulting in excessive SO2 at the desulfurization tower inlet. The desulfurization tower is difficult to reduce the sulfur content in the exhaust gas to below the standard line. Utility Model Content

[0004] In order to solve the problems existing in the above-mentioned prior art, the utility model provides a supergravity purification system for high-concentration hydrogen sulfide waste gas. By adding a supergravity machine, the contact surface area between the waste gas and the liquid is increased, the mass transfer coefficient and the reaction rate are effectively improved, which is conducive to promoting the elution of H2S and some organic matter in the non-condensable gas by alkaline solution, thereby reducing the sulfur content in the tail gas generated after the non-condensable gas is burned.

[0005] The specific technical solution adopted by the utility model is:

[0006] A supergravity purification system for high-concentration hydrogen sulfide waste gas comprises an asphalt reforming tower, an alkali solution tank and a combustion furnace, and also comprises a supergravity machine, wherein the exhaust end of the asphalt reforming tower is connected to the air inlet end of the supergravity machine, the liquid outlet end of the alkali solution tank is connected to the liquid inlet end of the supergravity machine, and the air outlet end of the supergravity machine is connected to the air inlet end of the combustion furnace.

[0007] The supergravity purification system also includes an alkali solution recovery system, which includes an alkali solution buffer tank, a first water pump, an alkali solution recovery tank and a second water pump. The alkali solution tank is connected to the supergravity machine by means of the alkali solution buffer tank. The washing alkali solution in the alkali solution buffer tank flows into the supergravity machine by means of the first water pump. The liquid outlet end of the supergravity machine is connected to the liquid inlet end of the alkali solution recovery tank. The liquid outlet end of the alkali solution recovery tank is connected to the liquid inlet end of the alkali solution tank. The washing alkali solution in the alkali solution recovery tank flows into the alkali solution tank by means of the second water pump.

[0008] A gas buffer tank is also provided between the supergravity machine and the combustion furnace, the input end of the gas buffer tank is connected to the liquid outlet end of the supergravity machine, and the output end of the gas buffer tank is connected to the air inlet end of the combustion furnace.

[0009] A demister and a fan are also provided between the gas buffer tank and the combustion furnace. The output end of the gas buffer tank is connected to the input end of the demister, and the output end of the demister is connected to the input end of the combustion furnace. The gas in the demister is introduced into the combustion furnace by means of the fan.

[0010] The fan has a total pressure of 3.0-3.2 KPa, a flow rate of 700-900 Nm3 / h, a power of 2-2.4 kW, a rotation speed of 2800-3000 r / min, and a gas pipeline diameter of 140-160 mm.

[0011] The diameter of the demister is 550-650 mm, and the thickness of the demister is 450-550 mm.

[0012] A hand hole is arranged on the shell of the supergravity machine, and the hand hole has the freedom of opening and closing by means of an opening and closing cover.

[0013] The opening of the alkali solution tank is provided with a cover plate.

[0014] The beneficial effects of the utility model are:

[0015] 1. The purification system of the utility model is equipped with a supergravity machine, which generates a supergravity field through high-speed rotation. The supergravity field is a centrifugal force field that exceeds the earth's gravity field generated by the high-speed rotation of the supergravity machine. The gas and liquid in the supergravity field are torn and atomized by the huge shear force, the specific surface area is increased, and the gas-liquid interface is quickly updated, the micro-mixing is strengthened, and the material transfer between fluid micro-groups is increased by 10 compared with the conventional gravity field. 2 ~10 3 When in use, the washing alkali liquid sprayed into the supergravity machine is torn into liquid film, liquid filaments and droplets on the rotor surface, which increases the contact surface area between the exhaust gas and the liquid, effectively improves the mass transfer coefficient and the reaction rate, and is beneficial to promote the elution of H2S and some organic matter in the non-condensable gas by the alkali liquid, thereby reducing the sulfur content in the exhaust gas produced after the non-condensable gas is burned.

[0016] 2. The super gravity machine can effectively remove H2S from the non-condensable gas of modified asphalt, thereby reducing the SO2 at the outlet of the combustion furnace. The super gravity machine is insensitive to changes in system pressure and can operate stably under negative pressure and slightly positive pressure processes, with a desulfurization efficiency of 90.6-93.7%.

[0017] Ultra-gravity machine desulfurization can effectively remove VOCs from non-condensable gases, with a removal efficiency of 91.7%, and can effectively remove large molecular sulfides. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is the process flow chart of the utility model;

[0019] Figure 2It is the structural diagram of the supergravity machine;

[0020] Figure 3 This is the SO2 variation curve of super gravity desulfurization;

[0021] In the attached drawings, 1. super gravity machine, 2. hand hole, 3. opening and closing cover. DETAILED DESCRIPTION

[0022] The utility model is further described below in conjunction with the accompanying drawings and specific embodiments: 1. Specific embodiments

[0024] Specific implementation examples Figure 1-2 As shown, the utility model provides an ultra-gravity purification system for high-concentration hydrogen sulfide waste gas, including an asphalt modifying tower, an alkali solution tank and a combustion furnace, and also includes an ultra-gravity machine 1, the exhaust end of the asphalt modifying tower is connected to the air inlet end of the ultra-gravity machine 1, the liquid outlet end of the alkali solution tank is connected to the liquid inlet end of the ultra-gravity machine 1, and the air outlet end of the ultra-gravity machine 1 is connected to the air inlet end of the combustion furnace.

[0025] Since the H2S content in the non-condensable gas produced by the asphalt reformer is high, the maximum concentration is 15000-20000mg / Nm 3 , exhaust gas flow rate is about 600-1200m 3 / h, the SO2 content in the gas after combustion is too high, resulting in excessive SO2 at the desulfurization tower inlet, and the desulfurization tower is difficult to reduce the sulfur content in the exhaust gas to below the standard line.

[0026] Therefore, a supergravity machine 1 is added to the purification system of the utility model. The supergravity machine 1 generates a supergravity field through high-speed rotation. The supergravity field is a centrifugal force field that exceeds the earth's gravity field generated by high-speed rotation. The gas and liquid in the supergravity field are torn and atomized by the huge shear force, the specific surface area is increased, and the gas-liquid interface is quickly updated, the micro-mixing is strengthened, and the material transfer between fluid micro-groups is increased by 10 compared with the conventional gravity field. 2 ~10 3 When in use, the washing alkali liquid sprayed into the supergravity machine 1 is torn into liquid film, liquid filaments and liquid droplets on the rotor surface, which increases the contact surface area between the exhaust gas and the liquid, effectively improves the mass transfer coefficient and the reaction rate, and is beneficial to promote the alkali liquid to wash out H2S and some organic matter in the non-condensable gas, thereby reducing the sulfur content in the exhaust gas generated after the non-condensable gas is burned.

[0027] The supergravity purification system also includes an alkali solution recovery system, which includes an alkali solution buffer tank, a first water pump, an alkali solution recovery tank and a second water pump. The alkali solution tank is connected to the supergravity machine 1 by means of the alkali solution buffer tank. The washing alkali solution in the alkali solution buffer tank flows into the supergravity machine 1 by means of the first water pump. The liquid outlet end of the supergravity machine 1 is connected to the liquid inlet end of the alkali solution recovery tank. The liquid outlet end of the alkali solution recovery tank is connected to the liquid inlet end of the alkali solution tank. The washing alkali solution in the alkali solution recovery tank flows into the alkali solution tank by means of the second water pump. In order to ensure the purification effect of hydrogen sulfide during the purification process, the input amount of alkali solution is excessive. In order to recover the excess alkali solution, an alkali solution recovery system is also provided in the utility model. After the alkali solution enters the alkali solution buffer tank through the alkali solution tank, the alkali solution in the alkali solution buffer tank is pumped into the supergravity machine 1 by a first water pump to wash the high-sulfur tail gas, wherein the alkali solution is a sodium hydroxide solution, and the sodium hydroxide solution reacts with hydrogen sulfide to generate sodium sulfide precipitate. The excess alkali solution will carry the sodium sulfide precipitate into the alkali solution recovery tank. After the sodium sulfide precipitate is filtered through the liquid-solid separator, the excess alkali solution re-enters the alkali solution tank by the second water pump and a new round of high-sulfur tail gas washing is carried out. At the same time, the alkali solution tank replenishes the alkali solution consumption every hour to keep the alkali solution in the alkali solution tank sufficient.

[0028] In addition, the alkali solution tank is also connected to the phenol extraction section. Since the alkali solution absorbs a small amount of organic matter in the process of washing high-sulfur tail gas, the organic matter content in the alkali solution tank will gradually increase during the continuous circulation purification process. Alkali solution with too high organic matter content will affect the washing effect of the alkali solution on high-sulfur tail gas. Therefore, it is necessary to regularly pass the alkali solution in the alkali solution tank into the phenol extraction section to recover the organic matter, and pass new high-purity alkali solution into the alkali solution tank.

[0029] A gas buffer tank is also provided between the supergravity machine 1 and the combustion furnace, the input end of the gas buffer tank is connected to the liquid outlet end of the supergravity machine 1, and the output end of the gas buffer tank is connected to the air inlet end of the combustion furnace. The gas buffer tank has a capacity of 2m 3 , wire mesh filler is added in the gas buffer tank to block solid particles in the gas.

[0030] A demister and a fan are also provided between the gas buffer tank and the combustion furnace. The output end of the gas buffer tank is connected to the input end of the demister, and the output end of the demister is connected to the input end of the combustion furnace. The gas in the demister is introduced into the combustion furnace by means of the fan. The exhaust gas after the super gravity machine 1 will carry water mist and a small amount of organic matter. The demister can further remove the organic matter and entrained moisture in the desulfurized gas, effectively preventing the gas from carrying water and affecting the stable operation of subsequent equipment.

[0031] The fan has a total pressure of 3.0-3.2KPa and a flow rate of 700-900Nm 3 / h, power 2-2.4kw, speed 2800-3000r / min, gas pipeline diameter 140-160mm.

[0032] The diameter of the demister is 550-650mm, the thickness of the demister is 450-550mm, the wire mesh filler in the demister can be replaced, and when a large number of particles adhere to the wire mesh filler, the wire mesh filler can be removed and placed in an alkaline solution for soaking and cleaning, so as to quickly remove the particles adhered to the wire mesh filler.

[0033] A hand hole 2 is provided on the shell of the ultra-gravity machine 1, and the hand hole 2 has the freedom of opening and closing with the help of an opening and closing cover 3. If the ultra-gravity machine 1 is not used for a long time, dry lumps will adhere to the surface of the internal rotor. At this time, the opening and closing cover 3 can be opened, and a high-pressure water gun can be used to quickly rinse and clean the rotor through the hand hole 2.

[0034] The opening of the alkali solution tank is provided with a cover plate, which can reduce the evaporation of water and the volatilization of odorous gases. A liquid level controller is also provided in the tank cavity of the alkali solution tank to control the alkali solution level and automatically add washing alkali solution.

[0035] 2. Experimental Test

[0036] 1. Test conditions

[0037] With 600Nm 3 The ultra-gravity machine 1 has a rotation speed of 1400r / min and a power of 1.5KW.

[0038] Circulation pump: power 1.5KW, liquid inlet valve fully open.

[0039] Alkali solution preparation: Use 29.32% sodium hydroxide solution, add an equal amount of water to dilute it to a concentration of about 14-15%, and the amount of alkali is 0.4m 3 .

[0040] Test index: SO2 content in the exhaust gas at the combustion furnace outlet.

[0041] 2. Test steps

[0042] S1, clean the super gravity machine 1, the first water pump, and the second water pump, and plug the leaks;

[0043] S2. Clean the alkali solution tank thoroughly, prepare alkali solution and add it into the alkali solution tank;

[0044] S3, start the supergravity machine 1, the first water pump, and the second water pump, introduce non-condensable gas, and detect the hydrogen sulfide content of the tail gas at the outlet of the supergravity machine 1;

[0045] S4. Send the tail gas in and detect the SO2 content at the outlet of the combustion furnace.

[0046] 3. Test data

[0047] Test data are shown in Tables 1-3 and Figure 3 .

[0048] Table 1 Ultra-gravity desulfurization hydrogen test 1

[0049]

[0050]

[0051] Table 2 High gravity desulfurization hydrogen test 2

[0052] time Oxygen content (%) <![CDATA[H2S(ppm)]]> 9:00 0 39 9:15 0 22 10:00 0 20

[0053] Table 3 Test of sending high gravity desulfurization tail gas to combustion furnace

[0054]

[0055] 4. Experimental data analysis

[0056] Tables 1 and 2 show the data of ultra-gravity desulfurization and detection of outlet hydrogen sulfide content. The instrument is replaced to an oxygen content of ≤1% for valid data. It can be seen from the above two groups of test data that the outlet hydrogen sulfide content is at a very low level.

[0057] Table 3 and Figure 3 The data of SO2 content in the exhaust gas at the outlet of the combustion furnace after the high-gravity desulfurization is used. From the test results, it can be seen that the high-gravity machine 1 reaches a stable operating state after running for 30 minutes and stops running for 90 minutes. The minimum value of SO2 content at the outlet of the combustion furnace is 157mg / Nm 3 , converted to 156mg / Nm 3 The average SO2 content is 187.4 mg / Nm 3 , converted to 188.8mg / Nm 3 Before desulfurization, the SO2 content at the outlet of the combustion furnace was estimated to reach 2000-3000mg / Nm 3 Based on this, the SO2 removal rate reached 90.6-93.7%, achieving the expected desulfurization purpose. During the test, the pressure was adjusted from -17kPa to a slightly positive pressure of 0-0.5kPa, and the desulfurization effect did not fluctuate significantly.

[0058] In addition, most of the organic matter can be removed by washing, and the non-condensable liquid discharge is reduced from 20kg / h to 40kg / day, a reduction of 91.7%.

Claims

1. A high-gravity purification system for high-concentration hydrogen sulfide waste gas, comprising an asphalt reforming tower, an alkali liquid tank and a combustion furnace, characterized in that: It also comprises a supergravity machine (1), wherein the exhaust end of the asphalt modification tower is connected to the air inlet end of the supergravity machine (1), the liquid outlet end of the alkali liquid tank is connected to the liquid inlet end of the supergravity machine (1), and the air outlet end of the supergravity machine (1) is connected to the air inlet end of the combustion furnace.

2. The ultra-gravity purification system for high-concentration hydrogen sulfide waste gas according to claim 1, characterized in that: The supergravity purification system also includes an alkali solution recovery system, which includes an alkali solution buffer tank, a first water pump, an alkali solution recovery tank and a second water pump. The alkali solution tank is connected to the supergravity machine (1) by means of the alkali solution buffer tank. The washing alkali solution in the alkali solution buffer tank flows into the supergravity machine (1) by means of the first water pump. The liquid outlet of the supergravity machine (1) is connected to the liquid inlet of the alkali solution recovery tank. The liquid outlet of the alkali solution recovery tank is connected to the liquid inlet of the alkali solution tank. The washing alkali solution in the alkali solution recovery tank flows into the alkali solution tank by means of the second water pump.

3. The ultra-gravity purification system for high-concentration hydrogen sulfide waste gas according to claim 1, characterized in that: A gas buffer tank is also provided between the supergravity machine (1) and the combustion furnace, wherein the input end of the gas buffer tank is connected to the liquid outlet end of the supergravity machine (1), and the output end of the gas buffer tank is connected to the air inlet end of the combustion furnace.

4. The ultra-gravity purification system for high-concentration hydrogen sulfide waste gas according to claim 3, characterized in that: A demister and a fan are also provided between the gas buffer tank and the combustion furnace. The output end of the gas buffer tank is connected to the input end of the demister, and the output end of the demister is connected to the input end of the combustion furnace. The gas in the demister is introduced into the combustion furnace by means of the fan.

5. The ultra-gravity purification system for high-concentration hydrogen sulfide waste gas according to claim 4, characterized in that: The fan has a total pressure of 3.0-3.2 KPa, a flow rate of 700-900 Nm3 / h, a power of 2-2.4 kW, a rotation speed of 2800-3000 r / min, and a gas pipeline diameter of 140-160 mm.

6. The ultra-gravity purification system for high-concentration hydrogen sulfide waste gas according to claim 4, characterized in that: The diameter of the demister is 550-650 mm, and the thickness of the demister is 450-550 mm.

7. The ultra-gravity purification system for high-concentration hydrogen sulfide waste gas according to claim 1, characterized in that: A hand hole (2) is provided on the shell of the supergravity machine (1), and the hand hole (2) has the freedom of opening and closing by means of an opening and closing cover (3).

8. The ultra-gravity purification system for high-concentration hydrogen sulfide waste gas according to claim 1, characterized in that: The opening of the alkali solution tank is provided with a cover plate.

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