CN118001915A - Tail gas treatment device of fermentation system - Google Patents

Abstract

The invention discloses a tail gas treatment device of a fermentation system, which comprises a hydrocyclone, a water sealed tank, an alkaline washing tower, a post-treatment tank and a tail gas fan. The tail gas inlet end of the hydrocyclone is connected with the fermentation tank through a gas phase pipe of the fermentation tank; the gas outlet at the top of the cyclone liquid separator is connected with a water seal tank through a gas outlet pipe of the cyclone liquid separator, the top of a water seal tank gas inlet distributor is connected with a gas outlet pipe of the cyclone liquid separator, the gas outlet at the top of the water seal tank is connected with an alkaline cleaning tower through a gas outlet pipe of the water seal tank, the top of the alkaline cleaning tower is provided with a centrifugal rotary spray head, the centrifugal rotary spray head is connected with a circulating pipeline of the alkaline cleaning tower, cooling pipes are arranged inside liquid tanks of the alkaline cleaning tower and the alkaline cleaning tower, the top of the alkaline cleaning tower is connected with a post-treatment tank through a gas outlet pipe of the alkaline cleaning tower, the top of the post-treatment tank is connected with a tail gas fan through a gas outlet pipe of the post-treatment tank, and the tail gas fan is connected with an exhaust pipe through a fan outlet pipe. The invention adopts a mode of combining physical absorption and chemical absorption, has simple process operation, low running cost and simple maintenance.

Description

Fermentation system tail gas treatment device

Technical Field

The invention relates to tail gas treatment, and in particular to a tail gas treatment device for a fermentation system.

Background technique

Bio-fermentation is the most commonly used reaction system in the microbial industry, which uses the specific biological functions of microorganisms or various enzymes to produce the corresponding target products. Bio-fermentation is widely used in agriculture, food, chemicals, medicines, new materials and other fields.

During the fermentation process, a large amount of sterile air needs to be blown in for the growth of microorganisms. Most of the air cannot be absorbed and utilized by the microorganisms and is discharged through the exhaust pipe. In the process of discharge, it will be mixed with some organic raw materials, semi-finished products or metabolites, and even strong irritating odors will be discharged, which pollutes the environment and causes certain harm to the human body.

The composition of fermentation waste gas is relatively complex, mainly including air released by the aeration system, metabolic products of bacteria, acidic and alkaline gases produced during the fermentation process, and various organic substances such as: acetone, butyl esters, butanol, ethyl acetate, benzene, toluene, xylene, methanol, n-propanol, dichloromethane, tetrahydrofuran, ethers, etc.

At present, most of the treatment methods have the disadvantages of low treatment efficiency and high operating costs. The use of membrane separation technology and molecular sieve technology with high investment has improved the separation efficiency, but the equipment investment is large, and consumable materials such as membrane components need to be replaced frequently, which is not an economical choice. The materials entrained in the gas phase of the fermentation system cannot be effectively recovered, which not only increases the waste of materials, but also increases the amount of sewage. The purification effect is poor, the guarantee rate of treatment compliance is not high, and the waste absorption liquid or solid waste generated during the treatment process needs further treatment, causing secondary pollution. The process operation is complicated, the operating cost is high, there are many consumable parts, and the maintenance cost is high. Fermentation pressure is crucial to the growth of microorganisms and fermentation reactions. Pressure fluctuations will affect the efficiency of fermentation. The pressure stability of the current fermentation system is poor. When fermentation is abnormal and sudden situations such as mist entrainment or bubbling occur, it may have a negative impact on the existing tail gas system, which is not conducive to the stable operation of the tail gas absorption system. After long-term operation, the tail gas absorption system is prone to bacterial contamination and the reproduction of bacteriophages. The connection with the fermentation system may increase the probability of bacterial contamination in the fermentation system, which is not conducive to the normal operation of the reaction system. There are no effective measures to prevent process materials and bacteria from entering the tail gas washing system along with the aerated tail gas, which increases the burden on the subsequent tail gas treatment system. The tail gas absorption system has high energy consumption, low operating efficiency, poor economy and sustainability. The unreasonable equipment design leads to a large footprint and high equipment investment cost.

Summary of the invention

The technical problem to be solved by the present invention is to provide a fermentation system tail gas treatment device, which at least achieves the purpose of improving the treatment efficiency and reducing the operating cost.

In order to solve the above technical problems, the technical solution adopted by the present invention is:

A fermentation system tail gas treatment device, comprising:

- Hydrocyclone separator, the tail gas inlet end of the hydrocyclone separator is connected to the fermentation tank through the fermentation tank gas phase pipe; the gas outlet at the top of the hydrocyclone separator is connected to the water seal tank through the hydrocyclone separator gas outlet pipe, and the liquid discharge port at the bottom of the hydrocyclone separator is connected to the fermentation tank through the hydrocyclone separator liquid outlet pipe;

——Water seal tank, a water seal tank air inlet distributor is arranged in the water seal tank, the top of the water seal tank air inlet distributor is connected to the cyclone separator air outlet pipe; the upper side wall of the water seal tank is connected to the water seal material overflow pipe, and the end of the water seal material overflow pipe is connected to the fermentation tank; the air outlet at the top of the water seal tank is connected to the alkali washing tower through the water seal tank air outlet pipe; the top of the water seal tank is connected to a sterile distilled water replenishing pipe for inputting sterile distilled water into the water seal tank;

——Alkali washing tower, a centrifugal rotating nozzle is arranged on the top of the alkali washing tower, an alkali washing tower receiving tank is arranged at the bottom of the alkali washing tower, the alkali washing tower receiving tank is connected to the alkali liquid discharge pipe, the centrifugal rotating nozzle is connected to the alkali washing tower circulation pipeline, the alkali liquid discharge pipe and the alkali washing tower circulation pipeline are respectively connected to the inlet and outlet ports of the alkali washing tower circulation pump; an alkali washing tower alkali liquid replenishing pipe for inputting alkali liquid is arranged on the alkali washing tower receiving tank, a cooling pipe is arranged inside the alkali washing tower and the alkali washing tower receiving tank, one end of the cooling pipe is connected to the alkali washing tower cooling water inlet pipe for inputting cooling water, and the other end of the cooling pipe is connected to the alkali washing tower cooling water outlet pipe; the upper side wall of the alkali washing tower receiving tank is connected to the alkali washing tower alkali liquid overflow pipe, the end of the alkali washing tower alkali liquid overflow pipe is connected to the alkali liquid receiving tank, and the alkali liquid receiving tank is connected to the fermentation tank through a pipeline; the top of the alkali washing tower is connected to the post-processing tank through the alkali washing tower outlet pipe;

——Post-processing tank, the bottom of the post-processing tank is connected to the alkali solution discharge pipe through the post-processing tank liquid sealing pipe, and the top of the post-processing tank is connected to the exhaust fan through the post-processing tank outlet pipe;

——Exhaust fan, the exhaust fan is connected to the exhaust pipe through the fan outlet pipe.

Furthermore, a fermentation system pressure sensor and a fermentation tank gas phase control valve are provided on the fermentation tank gas phase pipe.

Furthermore, a cyclone separator liquid outlet pipe gantry bend is provided on the liquid outlet pipe of the cyclone separator, and a cyclone separator liquid outlet pipe drain valve is connected to the bottom of the cyclone separator liquid outlet pipe gantry bend.

Furthermore, a water seal material liquid seal pipe is provided on the water seal material overflow pipe, and a liquid seal section drain valve is provided on the water seal material liquid seal pipe.

Furthermore, a grid filler layer is provided in the water seal tank.

Furthermore, a corrugated plate packing layer is installed at the upper part of the alkali washing tower, and a rectangular saddle ring random packing layer is installed at the lower part of the alkali washing tower.

Furthermore, a wire mesh structure layer is provided in the upper layer of the post-processing tank.

Furthermore, it comprises a sterilization system, wherein the sterilization system comprises a sterilization steam source, and the sterilization steam source is connected to the hydrocyclone separator, the water seal tank, the alkali washing tower and the alkali solution receiving tank through pipelines respectively.

The present invention adopts a combination of physical absorption and chemical absorption, and has simple process operation, low operating cost, strong controllability, good purification effect, high standard guarantee rate, no secondary pollution, simple maintenance, and can effectively deal with sudden situations such as mist entrainment and foaming caused by abnormal fermentation, and can recycle useful substances back into the system to avoid waste.

The present invention can ensure that process materials and bacterial solution are recycled into the system to participate in the reaction, and can also ensure that the tail gas entering the tail gas washing system is clean, thereby reducing the burden of subsequent treatment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a flow chart of a fermentation system tail gas treatment device provided by the present invention.

In the figure, 1-sterile air aeration pipe, 2-fermentation tank, 3-fermentation tank gas phase pipe, 4-cyclone separator, 5-cyclone separator outlet pipe, 6-cyclone separator sterilization steam pipe, 7-cyclone separator outlet pipe, 8-cyclone separator outlet pipe gantry bend, 9-cyclone separator outlet pipe drain valve, 10-water seal tank air inlet distributor, 11-water seal tank, 12-grid packing layer, 13-water seal material overflow pipe, 14-water seal material liquid seal pipe, 15-liquid seal section drain valve, 16-water seal tank sterilization steam pipe, 17-water seal tank outlet pipe, 18-sterile distilled water replenishment pipe, 19-alkali washing tower sterilization steam pipe, 20-alkali washing tower cooling water outlet pipe, 21-centrifugal rotating nozzle, 22-corrugated plate packing layer, 23-cooling pipe, 24-rectangular saddle Annular random packing layer, 25-alkali washing tower, 26-alkali washing tower liquid receiving tank, 27-alkali liquid discharge pipe, 28-alkali washing tower circulation pump, 29-alkali washing tower circulation pipeline, 30-post-treatment tank liquid seal pipe, 31-alkali washing tower air outlet pipe, 32-post-treatment tank, 33-wire mesh structure layer, 34-post-treatment tank air outlet pipe, 35-exhaust fan, 36-fan outlet pipe, 37-exhaust pipe, 38-alkali liquid overflow pipe of alkali washing tower, 39-alkali washing tower cooling water inlet pipe, 40-alkali liquid replenishing pipe of alkali washing tower, 41-alkali liquid receiving tank, 42-alkali liquid receiving tank sterilization steam pipe, 43-alkali liquid return pipe, 44-alkali liquid filter, 45-fermentation system alkali replenishing pump, 46-fermentation system alkali replenishing pipe, 47-fermentation system pressure sensor, 48-fermentation tank gas phase control valve.

Detailed ways

A typical embodiment of the present invention provides a fermentation system tail gas treatment device, as shown in FIG. 1 , which is mainly composed of a cyclone separator 4 , a water seal tank 11 , an alkali washing tower 25 , a post-treatment tank 32 and a tail gas fan 35 .

The tail gas inlet of the hydrocyclone 4 is connected to the fermenter 2 through the fermenter gas phase pipe 3. The gas outlet at the top of the hydrocyclone 4 is connected to the water seal tank 11 through the hydrocyclone gas outlet pipe 5, and the liquid discharge port at the bottom of the hydrocyclone 4 is connected to the fermenter 2 through the hydrocyclone liquid outlet pipe 7.

The bottom of the fermentation tank 2 is connected to a sterile air source via a sterile air aeration pipe 1. The tail gas treatment device provided in this embodiment treats the mixed gas generated by the fermentation tank 2 of the fermentation system.

The mixed gas produced by the fermentation tank 2 enters the hydrocyclone 4 through the fermentation tank gas phase pipe 3. Since the mixed gas may contain a small amount of liquid reactants and products, after the gas-liquid mixture enters the hydrocyclone 4, a rotating flow field is formed in the hydrocyclone 4. The density of the liquid is large and the density of the gas is small. In the rotating flow field, the high-density gas flows downward and the low-density gas flows upward, that is, the gas is discharged from the gas outlet at the top of the hydrocyclone 4, and the liquid is recovered from the liquid outlet at the bottom of the hydrocyclone 4 to the fermentation tank 2, thereby avoiding the waste of liquid materials and realizing an efficient gas-liquid separation process.

The fermentation tank gas phase pipe 3 is provided with a fermentation system pressure sensor 47 and a fermentation tank gas phase control valve 48. Since there are certain requirements for the pressure in the fermentation tank 2, the pressure of the fermentation tank 2 can be stabilized within a set range through the interlocking control of the fermentation system pressure sensor 47 and the fermentation tank gas phase control valve 48, such as: when the actual pressure value in the fermentation tank 2 is higher than the set value, the fermentation system pressure sensor 47 will give a signal to transmit to the fermentation tank gas phase control valve 48, and the valve opening will increase, thereby reducing the pressure of the fermentation tank 2 to the set value; when the actual pressure value in the fermentation tank 2 is lower than the set value, the fermentation system pressure sensor 47 will give a signal to transmit to the fermentation tank gas phase control valve 48, and the valve opening will decrease, thereby increasing the pressure of the fermentation tank 2 to the set value.

The cyclone outlet pipe 7 is provided with a cyclone outlet pipe gantry bend 8, and the bottom of the cyclone outlet pipe gantry bend 8 is connected with a cyclone outlet pipe drain valve 9. The gantry-shaped cyclone outlet pipe gantry bend 8 is provided on the liquid recovery pipeline, so that the cyclone outlet pipe 7 is always filled with liquid column, the fermentation system and the cyclone 4 are physically isolated, and the pressure is stabilized. The cyclone outlet pipe drain valve 9 is used for draining when the production is stopped.

Among them, a water seal tank air inlet distributor 10 is arranged in the water seal tank 11, and the top of the water seal tank air inlet distributor 10 is connected to the cyclone separator outlet pipe 5; the upper side wall of the water seal tank 11 is connected to the water seal material overflow pipe 13, and the end of the water seal material overflow pipe 13 is connected to the fermentation tank 2. The air outlet at the top of the water seal tank 11 is connected to the alkali washing tower 25 through the water seal tank outlet pipe 17. The top of the water seal tank 11 is connected to a sterile distilled water replenishment pipe 18 for inputting sterile distilled water into the water seal tank 11.

After separation by the hydrocyclone 4, most of the aggregated liquid is separated out, but some molecular organic components are still entrained in the gas phase. The separated gas phase enters the water seal tank 11 through the hydrocyclone outlet pipe 5. The water seal tank 11 adopts a 10-water seal tank air inlet distributor to inlet air, so that the air can be evenly distributed, and sterile distilled water is used as the absorption medium in the water seal tank. In the water seal tank, organic molecules will be captured by water and slowly float on the liquid surface. At this time, they overflow into the fermentation system through the water seal material overflow pipe 13, realizing the effective recycling of organic components.

A regular grid packing layer 12 is arranged in the middle of the water seal tank 11. By taking advantage of its small pressure drop, the gas phase and the liquid phase can be fully contacted without affecting the release of the gas phase.

In addition, in order to avoid gas phase turbulence, a water seal material liquid seal pipe 14 is designed on the water seal material overflow pipe 13, thereby physically isolating the water seal tank 11 and the fermentation tank, thereby stabilizing the pressure. A liquid seal section drain valve is provided on the water seal material liquid seal pipe 14.

Among them, a centrifugal rotating nozzle 21 is arranged at the top of the alkali washing tower 25, and an alkali washing tower receiving tank 26 is arranged at the bottom of the alkali washing tower 25. The alkali washing tower receiving tank 26 is connected to the alkali liquid discharge pipe 27, and the centrifugal rotating nozzle 21 is connected to the alkali washing tower circulation pipeline 29. The alkali liquid discharge pipe 27 and the alkali washing tower circulation pipeline 29 are respectively connected to the inlet and outlet ports of the alkali washing tower circulation pump 28. An alkali washing tower alkali liquid replenishing pipe 40 for inputting alkali liquid is arranged on the alkali washing tower receiving tank 26, and a cooling pipe 23 is arranged inside the alkali washing tower 25 and the alkali washing tower receiving tank 26. One end of the cooling pipe 23 is connected to the alkali washing tower cooling water inlet pipe 39 for inputting cooling water, and the other end of the cooling pipe 23 is connected to the alkali washing tower cooling water outlet pipe 2. The upper side wall of the alkali washing tower liquid receiving tank 26 is connected to the alkali washing tower alkali liquid overflow pipe 38, the end of the alkali washing tower alkali liquid overflow pipe 38 is connected to the alkali liquid receiving tank 41, and the alkali liquid receiving tank 41 is connected to the fermentation tank 2 through a pipeline; the top of the alkali washing tower 25 is connected to the post-treatment tank 32 through the alkali washing tower outlet pipe 31.

The gas phase passing through the water seal tank 11 enters the alkali washing tower 25 through the water seal tank outlet pipe 17, and the impurities in the final tail gas are thoroughly cleaned by liquid alkali. The alkali washing absorption liquid comes from the alkali washing tower alkali liquid replenishing pipe 40 and is stored in the alkali washing tower 26 at the bottom of the alkali washing tower 25. The alkali washing tower 25 and the alkali washing tower liquid receiving tank 26 are integrated designs, which can greatly save floor space and equipment investment. The liquid alkali in the alkali washing tower liquid receiving tank 26 is pumped to the top of the tower by the alkali washing tower circulating pump 28, and the liquid alkali is sprayed down from the top of the tower by the alkali washing tower circulating pipeline 29 and the centrifugal rotating nozzle 21. The function of the nozzle is to strengthen the initial distribution of the liquid phase. The gas phase enters through the bottom of the alkali washing tower 25, and the gas phase and the liquid phase are contacted in a countercurrent manner, so as to achieve the purpose of thorough tail gas washing. The alkali washing tower 25 will produce a temperature rise after running for a period of time, and the heat is taken away by the cooling effect of the cooling pipe 23, so as to ensure that the alkali solution has a stronger absorption effect at low temperatures. The serpentine cooling pipe 23 not only has the cooling function, but also plays the role of disturbing the water flow and air flow to avoid short-flow phenomenon, thereby enhancing the absorption effect to a certain extent.

The alkali washing tower 25 is provided with a corrugated plate packing layer 22 on the top, which has a simple structure and is more conducive to the distribution of alkali solution and the dispersion of airflow. The alkali washing tower 25 is provided with a rectangular saddle ring random packing layer 24 on the bottom, which has extremely strong corrosion resistance and excellent heat resistance. Its structural advantages are small resistance, large flux, good packing strength and rigidity, which is conducive to liquid distribution and increases gas channels. The flanges on both sides of the saddle and the toothed structure at the bottom of both ends jointly increase the specific surface area between the packings. The high porosity structure increases the flux of the packing and reduces the pressure drop, which greatly improves the mass transfer performance.

Since the acidity during the fermentation process decreases, in order to maintain the pH during the fermentation process, a certain amount of liquid alkali needs to be supplemented. At this time, the liquid alkali after tail gas absorption can be used as a supplement for this part of the liquid alkali. The alkali solution of the alkali washing tower 25 flows into the alkali solution receiving tank 41 through the alkali washing tower alkali solution overflow pipe 38 as a buffer, and then is transported to the fermentation tank 2 through the alkali solution material return pipe 43, the alkali solution filter 44, the fermentation system alkali supplementation pump 45 and the fermentation system alkali supplementation pipe 46. The supplementary amount is controlled according to the pH requirement of the liquid in the fermentation tank 2. The alkali solution is used as a fermentation system to adjust the pH, realize closed-loop circulation, do not produce additional waste alkali solution, and do not increase the load of sewage treatment.

The bottom of the post-processing tank 32 is connected to the alkali solution discharge pipe 27 through the post-processing tank liquid sealing pipe 30, and the top of the post-processing tank 32 is connected to the exhaust fan 35 through the post-processing tank outlet pipe 34. The exhaust fan 35 is connected to the exhaust pipe 37 through the fan outlet pipe 36.

The washed gas phase enters the post-treatment tank 32 for drying through the alkali washing tower outlet pipe 31. The dried clean gas enters the tail gas fan 35 through the post-treatment tank outlet pipe 34, and then is directly connected to the exhaust pipe 37 through the fan outlet pipe 36, that is, the tail gas that meets the treatment standards is discharged to the atmosphere.

A wire mesh structure layer 33 is designed in the middle and upper part of the post-processing tank 32, the purpose of which is to intercept the moisture in the exhaust gas and play a drying role. The intercepted moisture will return to the system through the post-processing tank liquid seal pipe 30.

In this embodiment, the sterilization system includes a sterilization steam source, which is connected to the hydrocyclone 4 through the hydrocyclone sterilization steam pipe 6, connected to the water seal tank 11 through the water seal tank sterilization steam pipe 16, connected to the alkali wash tower 25 through the alkali wash tower sterilization steam pipe 19, and connected to the alkali liquid receiving tank 41 through the alkali liquid receiving tank sterilization steam pipe 42. The sterilization system can avoid the generation of bacteriophages and contamination by miscellaneous bacteria, ensuring that the entire tail gas absorption treatment system operates in a sterile environment.

Claims (8)

1. A fermentation system tail gas treatment device, characterized by comprising:

The tail gas inlet end of the hydrocyclone is connected with the fermentation tank through a gas phase pipe of the fermentation tank; the gas outlet at the top of the hydrocyclone is connected with a water sealed tank through a gas outlet pipe of the hydrocyclone, and the liquid outlet at the bottom of the hydrocyclone is connected with a fermentation tank through a liquid outlet pipe of the hydrocyclone;

The water-sealed tank is internally provided with a water-sealed tank air inlet distributor, and the top of the water-sealed tank air inlet distributor is connected with an air outlet pipe of the cyclone liquid separator; the side wall of the middle upper part of the water sealed tank is connected with a water sealed material overflow pipe, and the tail end of the water sealed material overflow pipe is connected to the fermentation tank; the air outlet at the top of the water-sealed tank is connected with the alkaline washing tower through an air outlet pipe of the water-sealed tank; the top of the water sealed tank is connected with a sterile distilled water supplementing pipe for inputting sterile distilled water into the water sealed tank;

The top in the alkaline washing tower is provided with a centrifugal rotary spray head, the bottom of the alkaline washing tower is provided with an alkaline washing tower liquid receiving tank which is connected with an alkaline liquid discharging pipe, the centrifugal rotary spray head is connected with an alkaline washing tower circulating pipeline, and the alkaline liquid discharging pipe and the alkaline washing tower circulating pipeline are respectively connected with an alkaline washing tower circulating pump inlet and outlet port; an alkaline tower alkaline liquor replenishing pipe for inputting alkaline liquor is arranged on the alkaline tower liquid receiving tank, cooling pipes are arranged in the alkaline tower and the alkaline tower liquid receiving tank, one end of each cooling pipe is connected with an alkaline tower cooling water inlet pipe for inputting cooling water, and the other end of each cooling pipe is connected with an alkaline tower cooling water outlet pipe; the side wall of the upper part of the liquid receiving tank of the alkaline washing tower is connected with an alkaline liquid overflow pipe of the alkaline washing tower, the tail end of the alkaline liquid overflow pipe of the alkaline washing tower is connected to an alkaline liquid receiving tank, and the alkaline liquid receiving tank is connected to a fermentation tank through a pipeline; the top of the alkaline washing tower is connected with a post-treatment tank through an air outlet pipe of the alkaline washing tower;

the bottom of the post-treatment tank is connected with an alkali liquor discharging pipe through a post-treatment tank liquid sealing pipe, and the top of the post-treatment tank is connected with a tail gas fan through a post-treatment tank gas outlet pipe;

the tail gas fan is connected with the exhaust funnel through a fan outlet pipe.

2. The tail gas treatment device for a fermentation system of claim 1, wherein: the fermentation tank gas phase pipe is provided with a fermentation system pressure sensor and a fermentation tank gas phase control valve.

3. The tail gas treatment device for a fermentation system according to claim 1 or 2, characterized in that: the liquid outlet pipe of the hydrocyclone is provided with a liquid outlet pipe gantry bend of the hydrocyclone, and the bottom of the liquid outlet pipe gantry bend of the hydrocyclone is connected with a liquid outlet pipe drain valve of the hydrocyclone.

4. A tail gas treatment device for a fermentation system according to claim 3, wherein: the water seal material overflow pipe is provided with a water seal material liquid seal pipe, and the water seal material liquid seal pipe is provided with a liquid seal section exhaust valve.

5. The tail gas treatment device for a fermentation system of claim 4, wherein: and a grid packing layer is arranged in the water sealed tank.

6. The tail gas treatment device for a fermentation system according to claim 1 or 5, wherein: the upper part of the alkaline washing tower is provided with a corrugated plate packing layer, and the lower part of the alkaline washing tower is provided with a saddle ring scattered packing layer.

7. The tail gas treatment device for a fermentation system of claim 6, wherein: the upper layer of the post-treatment tank is provided with a silk screen structure layer.

8. The tail gas treatment device for a fermentation system according to claim 1 or 7, wherein: the device comprises a sterilization system, wherein the sterilization system comprises a sterilization steam source, and the sterilization steam source is respectively connected with a hydrocyclone, a water sealed tank, an alkaline washing tower and an alkaline liquid receiving tank through pipelines.