WO2024082652A1

WO2024082652A1 - Tail gas treatment system in crushing and sorting process of scrapped power lithium battery

Info

Publication number: WO2024082652A1
Application number: PCT/CN2023/099082
Authority: WO
Inventors: 黄庆; 苑文仪; 陆炎; 汤之杰; 滕诚尧; 陈云燕; 郭艺璠
Original assignee: 上海第二工业大学
Priority date: 2022-10-21
Filing date: 2023-06-08
Publication date: 2024-04-25
Also published as: ZA202302751B; CN115569479A

Abstract

A tail gas treatment system in the crushing and sorting process of a scrapped power lithium battery. The system comprises: a process water tank (1) used for storing process water; a cooling tower (2), wherein the process water tank (1) supplies water to the cooling tower (2), and the cooling tower (2) is used for cooling tail gas and humidifying and settling black powder mixed in the tail gas; a baghouse dust collector (3) used for performing baghouse dust collection on the tail gas delivered by the cooling tower (2); a filter bag dust collection device (6) fixedly mounted at the top of the baghouse dust collector (3); a wet-type gas washing tower (4) communicated with the baghouse dust collector (3) by means of a tail gas heating exchanger (7), the wet-type gas washing tower (4) being used for cooling and dehumidifying high-temperature tail gas in the baghouse dust collector (3) and absorbing acid gas; and an activated carbon adsorption tower (5) used for adsorbing and filtering tail gas discharged from the tail gas heating exchanger (7) and discharging the gas to the outside by means of a stack (9).

Description

An exhaust gas treatment system for the crushing and sorting process of scrapped power lithium batteries

Technical Field

The utility model relates to the technical field of environmental protection and waste gas treatment, in particular to a tail gas treatment system in the process of crushing and sorting scrapped power lithium batteries.

Background technique

With the rapid development of new energy vehicles in recent years, the amount of scrapped automotive power batteries has increased, and the recycling of scrap automotive power batteries has become a key issue of concern to relevant national departments. Among the technical methods for recycling scrap power batteries, disassembly and then pyrolysis in a pyrolysis furnace is currently one of the main methods. This method is simple and practical, and can fully recover valuable materials in scrap batteries. However, the organic waste gas generated by the pyrolysis furnace during the pyrolysis process is of high concentration, complex composition, and unpleasant odor, which places high requirements on the back-end waste gas treatment process.

Lithium-ion batteries are mainly composed of positive electrode materials, negative electrode materials, separators, binders, conductive agents, etc. Among them, the positive electrode materials mainly include lithium cobalt oxide, lithium manganese oxide, lithium iron phosphate and nickel-cobalt-manganese ternary materials or nickel-cobalt-aluminum ternary materials. Cobalt and lithium, as a rare metal element, have high recovery value. The recycling methods for retired or scrapped power lithium batteries include dry recycling, wet recycling and biological recycling. Regardless of the method, the battery must be disassembled, the monomers must be crushed, and the sorting must be pre-treated. During the pretreatment process, the electrolyte in the battery will evaporate and overflow. The main components of lithium battery electrolytes include solvents such as ethylene carbonate, ethyl methyl carbonate, propylene carbonate, dimethyl carbonate, etc., and solutes such as LiPF _6. When carbonate substances enter the gas, the VOCs in the gas will exceed the standard, and LiPF ₆ will hydrolyze when it comes into contact with water to generate acidic substances such as hydrogen fluoride and phosphoric acid, which seriously pollute the environment. Therefore, in the process of recycling scrapped power lithium batteries, the exhaust gas must be treated in an environmentally friendly manner. In addition, phosphoric acid and hydrofluoric acid are two Phosphoric acid and hydrofluoric acid are very valuable chemical raw materials. my country has to mine large quantities of them every year to produce phosphoric acid and hydrofluoric acid, which not only wastes resources but also damages the environment.

Lithium battery pole piece recycling and processing equipment can effectively crush and grind waste power battery pole pieces, greatly improving the powder removal rate, which is higher than 98%; the whole process realizes PLC automatic control and exhaust gas collection and treatment, effectively reducing the emission of dust and electrolyte, and realizing the environmentally friendly separation and recycling of various components of waste power battery pole pieces, greatly reducing personnel operation risks and environmental pollution; this method can significantly improve production capacity and easily realize industrial-grade mass production.

At present, there are two main ways to recycle power batteries: the first is to use batteries with a capacity less than 70%-80% of the original capacity in a cascade manner. These batteries can no longer meet the requirements of automobile use, but their remaining capacity can still be used in other places, such as home lighting, energy storage, as a power source, etc.; the second is to dismantle and recycle batteries with a capacity reduced to 50% or unusable. Regardless of the two methods, the power battery module needs to be disassembled for subsequent resource recovery and reuse. At the same time, the process will generate corresponding exhaust gas, which needs to be safely, efficiently and environmentally friendly to meet the standards before it can be discharged to reduce pollution to the environment.

There is currently no mainstream green and efficient waste power lithium battery dismantling and crushing exhaust gas treatment technology in the domestic and foreign markets. When the power battery of a new energy vehicle is retired, the entire scrapped power lithium battery is usually disassembled. Due to the different models of new energy vehicles, the internal and external structural design, module connection and placement of scrapped power lithium batteries are different, which means that the quantity and type of exhaust gas generated during unified disassembly are uneven, which faces great difficulties.

At present, when scrapped lithium batteries are disposed of to recover useful metals, they need to be crushed, dried and other processes, which will produce a lot of tail gas and dust. This increases the degree of environmental pollution and is also detrimental to the health of people around. Since the tail gas contains organic gas and is mixed with black powder dust generated during crushing, the conventional tail gas treatment device on the market will not be able to achieve the purpose of collecting black powder, and the treatment effect of the tail gas is not good. Therefore, it is necessary to develop a device for treating the tail gas generated during the crushing and sorting of scrapped power batteries, which can solve many problems in this regard and greatly improve work efficiency.

Utility Model Content

The purpose of the utility model is to provide an exhaust gas treatment system in the process of crushing and sorting scrapped power lithium batteries, so as to solve the problems existing in the above-mentioned prior art, and to realize the collection of black powder mixed in the exhaust gas, to efficiently, safely and environmentally treat the exhaust gas, and to reduce the pollution caused to the environment.

To achieve the above purpose, the utility model provides the following solution: The utility model provides an exhaust gas treatment system in the process of crushing and sorting scrapped power lithium batteries, including: a process water tank; the process water tank is used to store process water;

Cooling tower; the process water tank supplies water to the cooling tower; the cooling tower is used to cool the exhaust gas and humidify and settle a small amount of black powder mixed in the exhaust gas;

Bag dust collector; the bag dust collector is used to carry out bag dust removal on the tail gas transported by the cooling tower;

Filter bag dust removal device; the filter bag dust removal device is fixedly installed on the top of the bag dust collector;

Wet scrubber; the wet scrubber is connected to the bag filter through an exhaust gas heat exchanger; the wet scrubber is used to cool down and remove the high-temperature exhaust gas in the bag filter. Wet absorption of acid gases;

Activated carbon adsorption tower; used for adsorbing and filtering the exhaust gas discharged from the exhaust gas heating exchanger and discharging the gas to the outside through the chimney.

The process water tank is connected with a drainage pipe, a water supply pipe and a water outlet pipe; one end of the drainage pipe is connected to the side above the water level line of the process water tank; the other end of the drainage pipe is connected to the external drainage pipe; the water supply pipe connects the top of the process water tank with the industrial water pool; one end of the water outlet pipe is connected to the bottom of the process water tank, and a cooling water pump is installed at the other end of the water outlet pipe; the cooling water pump is connected to the cooling tower through a cooling water outlet door.

The cooling tower is connected with a cooling tower tail gas delivery pipeline, a cooling tower cooling water delivery pipeline, a cooling tower compressed air delivery pipeline, a cooling tower tail gas output pipeline and a black powder output pipeline; the cooling tower tail gas delivery pipeline is placed at one end of the top of the cooling tower to introduce the tail gas into the cooling tower; one end of the cooling tower cooling water delivery pipeline is fixedly connected to the cooling water outlet door, and the other end is connected to the top of the cooling tower; the cooling tower compressed air delivery pipeline connects the top surface of the cooling tower with a compressed air source; the cooling tower tail gas output pipeline is installed on the bottom side wall of the cooling tower, and the cooling tower tail gas output pipeline forms an angle of 60°-62° with the cooling tower side wall; the black powder output pipeline is installed on the bottom surface of the cooling tower through a cooling tower rotary valve;

The temperature in the cooling tower tail gas output pipeline is maintained at 150°C-155°C.

A cooling tower heater is also fixedly installed at the bottom of the cooling tower; and a cooling tower rotating scraper is also installed at the bottom of the inner cavity of the cooling tower.

The bag dust collector is connected to a bag dust collector tail gas delivery pipeline, a bag dust collector tail gas output pipeline, a bag dust collector compressed air delivery pipeline and a bag dust collector dust residue output pipe. One end of the bag filter exhaust gas delivery pipeline is connected to the cooling tower exhaust gas output pipeline, and the other end is connected to the middle of the bag filter, and the bag filter exhaust gas delivery pipeline is directly facing the filter bag in the bag filter; the bag filter exhaust gas delivery pipeline is also provided with a dry powder addition port for adding slaked lime powder and activated carbon powder;

One end of the bag-type dust collector exhaust gas output pipe is connected to one side of the top of the bag-type dust collector; a bag outlet baffle is installed at the other end of the bag-type dust collector exhaust gas output pipe; compressed air is introduced into the compressed air delivery pipe of the bag-type dust collector; the compressed air is also introduced into the filter bag dust removal device through the purging compressed air delivery pipe; the dust residue output pipe of the bag-type dust collector is installed at the bottom of the bag-type dust collector.

A bag dust bin baffle is also installed on the top of the inner cavity of the bag dust collector; a vibration compressed air device is arranged under the filter bag; the bag dust collector exhaust gas delivery pipeline and the bag dust collector exhaust gas output pipeline are also directly connected through a bag heater and a heating fan to ensure that the exhaust gas temperature is maintained above 155°C; the bag heater is also introduced with purge air.

The filter bag dust removal device includes a pulse air bag and an air blowing pipe; the purge compressed air delivery pipeline is connected to the top of the pulse air bag; a plurality of air blowing pipes are installed at the bottom of the pulse air bag; the air blowing pipe extends into the bag dust collector and is arranged directly opposite to the filter bag; and a plurality of air blowing control valves are installed on the air blowing pipe.

The exhaust gas heating exchanger is connected with an exhaust gas heating input pipeline, an exhaust gas heating output pipeline, an exhaust gas heating exchanger exhaust gas output pipeline, an exhaust gas cooling input pipeline and an exhaust gas cooling output pipeline; one end of the exhaust gas cooling input pipeline is installed on the bag outlet baffle, and the other end of the exhaust gas cooling input pipeline is connected to the bottom of the exhaust gas heating exchanger; one end of the exhaust gas cooling output pipeline is connected to the bottom of the exhaust gas heating exchanger, and the exhaust gas cooling output pipeline is connected to the bottom of the exhaust gas heating exchanger. The other end of the pipeline is connected to the bottom of the wet scrubber; the exhaust gas heating input pipeline is connected to the top of the wet scrubber; the exhaust gas heating output pipeline is connected to the exhaust gas output pipeline of the exhaust gas heating exchanger and the purge air heater respectively; the exhaust gas output pipeline of the exhaust gas heating exchanger is connected to the activated carbon adsorption tower.

The wet scrubber is connected to the exhaust gas cooling output pipeline through the wet scrubber exhaust gas output pipeline; and a wet scrubber inlet baffle is also installed on the wet scrubber exhaust gas output pipeline; the top of the wet scrubber is connected to the exhaust gas heating input pipeline through the wet scrubber exhaust gas input pipeline; the top of the wet scrubber is also connected to the dehumidification water delivery pipeline; a dehumidification water discharge pipeline is arranged below the dehumidification water delivery pipeline; a cooling water delivery pipeline is arranged below the dehumidification water discharge pipeline; a secondary dehumidification water delivery pipeline is connected to the middle part of the wet scrubber; the bottom of the wet scrubber is also connected to a cooling water pH meter input pipeline and a salinity meter input water pipeline; the bottom of the wet scrubber is also equipped with a cooling water output port and a cooling water drain gate.

The activated carbon adsorption tower is connected to the exhaust gas output pipeline of the exhaust gas heating exchanger through the hot air purge pipeline and the activated carbon adsorption tower exhaust gas inlet pipeline; the activated carbon adsorption tower is connected to the chimney through the activated carbon adsorption tower exhaust gas output pipeline and the induced draft fan.

The utility model discloses the following technical effects: the system adopts dry method to treat exhaust gas and is easy to maintain; the design of cooling tower is compact and optimized; the system has good controllability for load changes; the overall pressure difference is very low, which can save the power of induced draft fan; the system has high integration and is easy to operate.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the utility model or the prior art, The following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

FIG1 is a schematic diagram of the structure of the utility model system;

FIG2 is a schematic diagram of the structure of the process water tank of the utility model system;

FIG3 is a schematic diagram of the internal structure of a cooling tower of the utility model system;

FIG4 is a schematic diagram of the structure of a bag filter system of the utility model;

FIG5 is a schematic diagram of the structure of a wet scrubber of the utility model system;

Figure 6 is a schematic diagram of the structure of the activated carbon of the utility model system. Among them, 1-process water tank, 101-drainage pipeline, 102-water supply pipeline, 103-water outlet pipeline, 104-external pipeline, 105-cooling water pump, 106-cooling water outlet door, 2-cooling tower, 201-cooling tower tail gas delivery pipeline, 202-cooling tower cooling water delivery pipeline, 203-cooling tower compressed air delivery pipeline, 204-cooling tower heater, 205-cooling tower tail gas output pipeline, 206-cooling tower rotary valve, 207-black powder output pipeline, 208-cooling tower rotary scraper, 3-bag dust collector, 301-bag dust collector tail gas delivery pipeline, 302-filter bag, 303-bag dust collector tail gas output pipeline, 3 04-bag outlet baffle, 305-bag dust collector bin baffle, 306-vibrating compressed air device, 307-bag heater, 308-bag dust collector compressed air delivery pipeline, 309-bag dust collector dust output pipeline, 310-purge compressed air delivery pipeline, 311-compressed air, 312-purge air, 313-slaked lime powder, 314-activated carbon powder, 4-wet scrubber, 401-wet scrubber tail gas output pipeline, 402-wet scrubber inlet baffle, 403-wet scrubber tail gas input pipeline, 404-dehumidification water delivery pipeline, 405-dehumidification water discharge pipeline, 406-cooling water delivery pipeline, 407- Secondary dehumidification water delivery pipeline, 408-cooling water pH meter input pipeline, 409-salinity meter input water pipeline, 410-cooling water output port, 411-cooling water drain gate, 5-activated carbon adsorption tower, 501-hot air purge pipeline, 502-activated carbon adsorption tower tail gas inlet pipeline, 503-activated carbon adsorption tower tail gas output pipeline, 504-induced draft fan, 6-filter bag dust removal device, 601-pulse air bag, 602-air blowing pipe, 603-air blowing control valve, 7-tail gas heating exchanger, 701-tail gas heating input pipeline, 702-tail gas heating output pipeline, 703-heating exchanger tail gas output pipeline, 704-tail gas cooling input pipeline, 705-tail gas cooling output pipeline, 706-purge air heater, 8-bag heater, 9-chimney.

Detailed ways

The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

The utility model provides an exhaust gas treatment system in the process of crushing and sorting scrapped power lithium batteries, comprising: a process water tank 1; the process water tank 1 is used to store process water;

Cooling tower 2; process water tank 1 supplies water to cooling tower 2; cooling tower 2 is used to cool the exhaust gas and humidify and settle the black powder in the exhaust gas;

Bag dust collector 3; bag dust collector 3 is used to carry out bag dust removal on the exhaust gas transported by cooling tower 2;

The filter bag dust removal device 6 is fixedly mounted on the top of the bag dust collector 3;

Wet scrubber 4; the wet scrubber 4 is connected to the bag filter 3 through the exhaust gas heating exchanger 7; the wet scrubber 4 is used to cool and dehumidify the high-temperature exhaust gas in the bag filter 3;

The activated carbon adsorption tower 5 is used to adsorb and filter the exhaust gas discharged from the exhaust gas heating exchanger 7 and discharge the gas to the outside through the chimney 9.

Further, in the present invention, a process water tank 1 is used to store process water and supply water to a cooling tower and a wet scrubber;

Cooling tower 2, which is used to cool the exhaust gas and humidify the black powder in the exhaust gas to make it settle and facilitate collection;

The bag filter 3 is used to remove dust from the slaked lime and activated carbon added in the dry exhaust gas treatment, forming a filter cake composed of slaked lime and activated carbon on the bag to strengthen the chemical reaction of the exhaust gas;

The filter bag dust removal device 6 is used to clean the filter cake on the bag and remove dust from the bag when the pressure difference on both sides of the bag reaches a trigger value;

Wet scrubber 4, which is used to cool the tail gas to 60°C-70°C, reduce the absorption saturation, and absorb acidic gases;

The tail gas heating exchanger 7 is used to heat the tail gas after being cooled in the wet scrubber to about 135°C to reduce the consumption of water vapor;

An activated carbon adsorption tower 5, which is used to adsorb and filter the tail gas;

A chimney 9, which is used to discharge the purified exhaust gas;

The bag heater 8 is used to keep the exhaust gas temperature at a high temperature (above 155° C.) to ensure that there is no corrosion problem caused by condensed water.

In one embodiment of the utility model, the exhaust gas inlet temperature of the cooling tower 2 is maintained at about 200°C, and the outlet temperature is about 155°C; the bag filter 3 is about 155-150°C during the entire treatment process; the temperature between the bag filter 3 and the inlet of the exhaust gas heating exchanger 7 is about 150°C, the exhaust gas heating exchanger 7 heats the outlet to 97-103°C, the wet scrubber 4 inlet is 97-103°C, and the outlet is 45-62°C; the exhaust gas heating exchanger 7 is heated at the inlet to 45-62°C, and the outlet is about 135°C.

The process water tank 1 is connected with a drainage pipe 101, a water supply pipe 102 and a water outlet pipe 103; one end of the drainage pipe 101 is connected to the side above the water level line of the process water tank 1; the other end of the drainage pipe 101 is connected with an external drainage pipe 104; the water supply pipe 102 connects the top of the process water tank 1 with the industrial water pool; one end of the water outlet pipe 103 is connected with the bottom of the process water tank 1, and a cooling water pump 105 is installed at the other end of the water outlet pipe 103; the cooling water pump 105 is connected with the cooling tower 2 through a cooling water outlet door 106.

The cooling tower 2 is connected with a cooling tower tail gas delivery pipeline 201, a cooling tower cooling water delivery pipeline 202, a cooling tower compressed air delivery pipeline 203, a cooling tower tail gas output pipeline 205 and a black powder output pipeline 207; the cooling tower tail gas delivery pipeline 201 is placed at one end of the top of the cooling tower 2 to introduce the tail gas into the cooling tower 2; one end of the cooling tower cooling water delivery pipeline 202 is fixedly connected to the cooling water outlet door 106, and the other end is connected to the top of the cooling tower 2; the cooling tower compressed air delivery pipeline 203 connects the top surface of the cooling tower 2 with the compressed air source; the cooling tower tail gas output pipeline 205 is installed on the bottom side wall of the cooling tower, and the cooling tower tail gas output pipeline 205 forms an angle of 60°-62° with the side wall of the cooling tower 2; the black powder output pipeline 207 is installed on the bottom surface of the cooling tower 2 through the cooling tower rotary valve 206;

The temperature in the cooling tower tail gas output pipe 205 is maintained at 150°C-155°C.

A cooling tower heater 204 is also fixedly installed at the bottom of the cooling tower 2; a cooling tower rotating scraper 208 is also installed at the bottom of the inner cavity of the cooling tower 2.

The bag-type dust collector 3 is connected with a bag-type dust collector tail gas delivery pipeline 301, a bag-type dust collector tail gas output pipeline 303, a bag-type dust collector compressed air delivery pipeline 308 and a bag-type dust collector dust residue output pipeline 309; one end of the bag-type dust collector tail gas delivery pipeline 301 is connected with the cooling tower tail gas output pipeline 205, and the other end is connected with the middle of the bag-type dust collector 3, and the bag-type dust collector tail gas delivery pipeline 301 is directly opposite to the filter bag 302 in the bag-type dust collector 3; the bag-type dust collector tail gas delivery pipeline 301 is also provided with a dry powder addition port for adding slaked lime powder 313 and activated carbon powder 314;

One end of the bag-type dust collector exhaust gas output pipe 303 is connected to one side of the top of the bag-type dust collector 3; the other end of the bag-type dust collector exhaust gas output pipe 303 is installed with a bag outlet baffle 304; compressed air 311 is introduced into the bag-type dust collector compressed air delivery pipe 308; compressed air 311 is also introduced into the filter bag dust removal device 6 through the purge compressed air delivery pipe 310; the bag-type dust residue output pipe 309 is installed at the bottom of the bag-type dust collector 3.

A bag dust bin baffle 305 is also installed on the top of the inner cavity of the bag dust collector 3; a vibration compressed air device 306 is arranged under the filter bag 302; the bag dust collector exhaust gas delivery pipeline 301 and the bag dust collector exhaust gas output pipeline 303 are also directly connected through the bag dust collector heater 307 and the heating fan to ensure that the exhaust gas temperature is maintained above 155°C; the bag dust collector 307 is also introduced with purge air 312.

Furthermore, in this embodiment, the vibrating compressed air device 306 is an existing device, which provides power through compressed air to make the piston move up and down to vibrate the filter bag 302 to shake off the dust.

The filter bag dust removal device 6 includes a pulse air bag 601 and an air blowing pipe 602; the purge compressed air delivery pipeline 310 is connected to the top of the pulse air bag 601; a plurality of air blowing pipes 602 are installed at the bottom of the pulse air bag 601; the air blowing pipe 602 extends into the bag dust collector 3 and is arranged directly opposite the filter bag 302; and a plurality of air blowing control valves 603 are installed on the air blowing pipe 602.

The exhaust gas heating exchanger 7 is connected with an exhaust gas heating input pipeline 701, an exhaust gas heating output pipeline 702, an exhaust gas heating exchanger exhaust gas output pipeline 703, an exhaust gas cooling input pipeline 704 and an exhaust gas cooling output pipeline 705; one end of the exhaust gas cooling input pipeline 704 is installed on the bag outlet baffle 304, and the other end of the exhaust gas cooling input pipeline 704 is connected to the bottom of the exhaust gas heating exchanger 7; one end of the exhaust gas cooling output pipeline 705 is connected to the bottom of the exhaust gas heating exchanger 7, and the other end of the exhaust gas cooling output pipeline 705 is connected to the bottom of the wet scrubber 4; the exhaust gas heating input pipeline 701 is connected to the top of the wet scrubber 4; the exhaust gas heating output pipeline 702 is respectively connected to the exhaust gas heating exchanger exhaust gas output pipeline 703 and the purge air heater 706; the exhaust gas heating exchanger exhaust gas output pipeline 703 is connected to the activated carbon adsorption tower 5.

Furthermore, the purge air heater 706 can be used to preheat the pipe connected to the exhaust gas heating exchanger 7 when the exhaust gas heating exchanger 7 is started; the purge air heater 706 can also be used to provide supplementary heat when the pipe temperature in the exhaust gas heating exchanger 7 does not reach the required temperature.

The wet scrubber 4 is connected to the tail gas cooling output pipeline 705 through the wet scrubber tail gas output pipeline 401; and a wet scrubber inlet baffle 402 is also installed on the wet scrubber tail gas output pipeline 401; the top of the wet scrubber 4 is connected to the tail gas heating input pipeline 701 through the wet scrubber tail gas input pipeline 403; the top of the wet scrubber 4 is also connected to the dehumidification water delivery pipeline 404; a dehumidification water discharge pipeline 405 is arranged below the dehumidification water delivery pipeline 404; A cooling water delivery pipeline 406 is arranged below the dehumidification water discharge pipeline 405; a secondary dehumidification water delivery pipeline 407 is connected to the middle of the wet scrubbing tower 4; a cooling water pH meter input pipeline 408 and a salinity meter input water pipeline 409 are also connected to the bottom of the wet scrubbing tower 4; a cooling water outlet 410 and a cooling water drain gate 411 are also installed at the bottom of the wet scrubbing tower 4.

The activated carbon adsorption tower 5 is connected to the exhaust gas output pipeline 703 of the exhaust heating exchanger through the hot air purge pipeline 501 and the activated carbon adsorption tower exhaust gas inlet pipeline 502; the activated carbon adsorption tower 5 is connected to the chimney 9 through the activated carbon adsorption tower exhaust gas output pipeline 503 and the induced draft fan 504.

Furthermore, as shown in FIG1 , the pipeline beside the activated carbon adsorption tower 5 is an auxiliary pipeline for blowing and cleaning.

In one embodiment of the utility model, when the utility model treats the tail gas, the black powder mixed in the tail gas is recovered by the cooling tower 2, and the tail gas pipeline between the cooling tower 2 and the bag filter 3 is sprayed with slaked lime 313 and activated carbon powder 314 for dry treatment, and the tail gas is preliminarily treated. The bag filter 3, the wet water scrubber 4, and the activated carbon adsorption tower 5 further purify the tail gas and discharge it to the atmosphere through the tail gas discharge chimney 9. Powdered activated carbon is sprayed into the flue between the cooling tower 2 and the bag filter 4 to remove harmful substances such as heavy metals and dioxins in the tail gas. In the bag filter 3, the unreacted calcium hydroxide and the acidic harmful gas in the tail gas continue to react, further improving the removal efficiency. Powdered slaked lime 313 is sprayed into the flue between the cooling tower 2 and the bag filter 3, so that the acidic gas in the tail gas reacts with the calcium hydroxide first and then is absorbed and removed, reducing the processing load of the wet scrubber. The exhaust gas temperature in the bag filter 3 is always kept high (above 155°C) to ensure that there will be no corrosion caused by condensed water. The dust in the exhaust gas is filtered by the bag and cleaned by online air, and then falls into the dust removal bin at the bottom of the bag filter. The dust discharge valve sends the dust to the dust output pipe 309 below it and sends it out. In order to prevent the bag filter 3 from low temperature corrosion during startup, a bag bottom heater 307 is set to preheat the bag filter.

After dust removal, the tail gas at about 150℃ enters the wet scrubber 4 through the exhaust gas inlet at the bottom of the wet scrubber 4 through the induced draft fan. The tail gas passes through the cooling part at the bottom of the scrubber 4 and the absorption and dehumidification part at the top. The coolant circulation pump sends the coolant at the bottom of the tower to the nozzle above the cooling part, sprays it downward to fully contact with the countercurrent tail gas, and reduces the tail gas temperature to the saturation temperature of 60-70℃ to enhance the ability of the alkaline liquid to absorb acidic gas. The tail gas after cooling and absorbing acidic gas enters the absorption and dehumidification part at the top of the scrubber. The dehumidification water from the dehumidification water tank is sent by the dehumidification water circulation pump, cooled by the heat exchanger, and then transported to the nozzle above the absorption and dehumidification part and sprayed downward, evenly passing through the packing bed and fully contacting with the tail gas, dehumidifying the water in the tail gas. The dehumidification water returns to the dehumidification water tank to form a cycle. In the absorption and dehumidification part, the tail gas temperature is further reduced, and the water content in the tail gas is also reduced accordingly. In this way, the chimney 9 caused by water vapor is prevented from emitting white smoke, and the acid gas concentration in the tail gas will be further reduced because the low temperature will promote the absorption of acid gas by alkali solution. The scrubbing wastewater is introduced into the wastewater treatment system. The sodium hydroxide as alkali solution is transported by a tanker and stored in a sodium hydroxide storage tank. The sodium hydroxide dilution pump transfers the sodium hydroxide into the sodium hydroxide dilution tank and is diluted to 10%. The diluted sodium hydroxide solution is transported to the inlet pipe of the coolant circulation pump and the inlet pipe of the dehumidifying liquid circulation pump by the sodium hydroxide supply pump. Thus, the acid gas in the tail gas that is not removed after the dry purification fully reacts with the sodium hydroxide solution of the wet scrubbing, further reducing the concentration and being thoroughly purified.

After the purified tail gas is demisted by the demister at the top of the wet scrubber 4, it is heat exchanged with the tail gas at the scrubber inlet in the tail gas heater installed at the inlet of the wet scrubber system. The temperature is further raised to about 135°C by a steam heater (in principle, no white smoke is visible in winter). The tail gas-tail gas heater is set to increase the temperature after wet scrubbing and minimize steam consumption.

Finally, the heated exhaust gas is filtered through an activated carbon adsorption device and discharged into the atmosphere through a chimney.

In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

The embodiments described above are only descriptions of the preferred methods of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the protection scope determined by the claims of the present invention.

Claims

A tail gas treatment system in a process of crushing and sorting scrapped power lithium batteries, characterized in that it comprises: a process water tank (1); the process water tank (1) is used to store process water;

Cooling tower (2); the process water tank (1) supplies water to the cooling tower (2); the cooling tower (2) is used to cool the exhaust gas and humidify and settle the black powder mixed in the exhaust gas;

Bag dust collector (3); the bag dust collector (3) is used to carry out bag dust removal on the tail gas transported by the cooling tower (2);

A filter bag dust removal device (6); the filter bag dust removal device (6) is fixedly installed on the top of the bag dust collector (3);

A wet scrubber (4); the wet scrubber (4) is connected to the bag filter (3) via an exhaust gas heating exchanger (7); the wet scrubber (4) is used to cool and dehumidify the high-temperature exhaust gas in the bag filter (3) and absorb acidic gases;

An activated carbon adsorption tower (5) is used to adsorb and filter the tail gas discharged from the tail gas heating exchanger (7) and discharge the gas to the outside through a chimney (9).
According to claim 1, a tail gas treatment system in the process of crushing and sorting scrapped power lithium batteries is characterized in that: the process water tank (1) is connected with a drainage pipe (101), a water supply pipe (102) and a water outlet pipe (103); one end of the drainage pipe (101) is connected to the side above the water level of the process water tank (1); the other end of the drainage pipe (101) is connected to an external drainage pipe (104); the water supply pipe (102) connects the top of the process water tank (1) with an industrial water pool; one end of the water outlet pipe (103) is connected to the bottom of the process water tank (1), and the other end of the water outlet pipe (103) is installed with a cooling water pump (105); the cooling water pump (105) is connected to the cooling tower (2) through a cooling water outlet door (106). Connectivity.
According to claim 2, a waste power lithium battery crushing and sorting process exhaust gas treatment system is characterized in that: the cooling tower (2) is connected to a cooling tower exhaust gas delivery pipeline (201), a cooling tower cooling water delivery pipeline (202), a cooling tower compressed air delivery pipeline (203), a cooling tower exhaust gas output pipeline (205) and a black powder output pipeline (207); the cooling tower exhaust gas delivery pipeline (201) is placed at one end of the top of the cooling tower (2) to guide the exhaust gas into the cooling tower (2); the cooling tower cooling water delivery pipeline (202) is connected to the cooling tower (2) to guide the exhaust gas into the cooling tower (2); the cooling tower cooling water delivery pipeline (203 ... 02) one end is fixedly connected to the cooling water outlet door (106), and the other end is connected to the top of the cooling tower (2); the cooling tower compressed air delivery pipeline (203) connects the top surface of the cooling tower (2) with the compressed air source; the cooling tower tail gas output pipeline (205) is installed on the bottom side wall of the cooling tower, and the cooling tower tail gas output pipeline (205) and the side wall of the cooling tower (2) form an angle of 60°-62°; the black powder output pipeline (207) is installed on the bottom surface of the cooling tower (2) through a cooling tower rotary valve (206);

The temperature in the cooling tower tail gas output pipeline (205) is maintained at 150°C-155°C.
According to the exhaust gas treatment system in the process of crushing and sorting scrapped power lithium batteries as described in claim 3, it is characterized in that: a cooling tower heater (204) is also fixedly installed at the bottom of the cooling tower (2); and a cooling tower rotating scraper (208) is also installed at the bottom of the inner cavity of the cooling tower (2).
According to claim 3, the exhaust gas treatment system in the process of crushing and sorting scrapped power lithium batteries is characterized in that: the bag dust collector (3) is connected to a bag dust collector exhaust gas delivery pipeline (301), a bag dust collector exhaust gas output pipeline (303), a bag dust collector compressed air delivery pipeline (308) and a bag dust collector dust residue output pipeline (309); One end of the bag filter exhaust gas delivery pipeline (301) is connected to the cooling tower exhaust gas output pipeline (205), and the other end is connected to the middle of the bag filter (3), and the bag filter exhaust gas delivery pipeline (301) is directly opposite to the filter bag (302) in the bag filter (3); the bag filter exhaust gas delivery pipeline (301) is also provided with a dry powder addition port for adding slaked lime powder (313) and activated carbon powder (314);

One end of the bag filter exhaust gas output pipe (303) is connected to one side of the top of the bag filter (3); the other end of the bag filter exhaust gas output pipe (303) is installed with a bag outlet baffle (304); compressed air (311) is introduced into the bag filter compressed air delivery pipe (308); the compressed air (311) is also introduced into the filter bag dust removal device (6) through the purge compressed air delivery pipe (310); the bag filter dust residue output pipe (309) is installed at the bottom of the bag filter (3).
According to claim 5, a waste gas treatment system in the crushing and sorting process of scrapped power lithium batteries is characterized in that: a bag dust collector bin baffle (305) is also installed on the top of the inner cavity of the bag dust collector (3); a vibration compressed air device (306) is arranged below the filter bag (302); the bag dust collector exhaust gas delivery pipeline (301) and the bag dust collector exhaust gas output pipeline (303) are also directly connected to the heating fan through the bag heater (307) to ensure that the exhaust gas temperature is maintained above 155°C; the bag heater (307) is also introduced with purge air (312).
According to claim 5, a tail gas treatment system in the process of crushing and sorting scrapped power lithium batteries is characterized in that: the filter bag dust removal device (6) includes a pulse air bag (601) and a blowing pipe (602); the purge compressed air delivery pipeline (310) is connected to the top of the pulse air bag (601); the bottom of the pulse air bag (601) is equipped with a plurality of The air blowing pipe (602) extends into the bag filter (3) and is arranged directly opposite to the filter bag (302); a plurality of air blowing control valves (603) are installed on the air blowing pipe (602).
According to claim 5, a waste gas treatment system in the crushing and sorting process of scrapped power lithium batteries is characterized in that: the exhaust gas heating exchanger (7) is connected to the exhaust gas heating input pipeline (701), the exhaust gas heating output pipeline (702), the exhaust gas heating exchanger exhaust gas output pipeline (703), the exhaust gas cooling input pipeline (704) and the exhaust gas cooling output pipeline (705); one end of the exhaust gas cooling input pipeline (704) is installed on the bag outlet baffle (304), and the other end of the exhaust gas cooling input pipeline (704) is connected to the exhaust gas heating exchanger ( 7) is connected to the bottom; one end of the exhaust gas cooling output pipeline (705) is connected to the bottom of the exhaust gas heating exchanger (7), and the other end of the exhaust gas cooling output pipeline (705) is connected to the bottom of the wet scrubber (4); the exhaust gas heating input pipeline (701) is connected to the top of the wet scrubber (4); the exhaust gas heating output pipeline (702) is connected to the exhaust gas heating exchanger exhaust gas output pipeline (703) and the purge air heater (706) respectively; the exhaust gas heating exchanger exhaust gas output pipeline (703) is connected to the activated carbon adsorption tower (5).
According to claim 8, a tail gas treatment system in the process of crushing and sorting scrapped power lithium batteries is characterized in that: the wet scrubber (4) is connected to the tail gas cooling output pipeline (705) through the wet scrubber tail gas output pipeline (401); and a wet scrubber inlet baffle (402) is also installed on the wet scrubber tail gas output pipeline (401); the top of the wet scrubber (4) is connected to the tail gas heating input pipeline (701) through the wet scrubber tail gas input pipeline (403); the top of the wet scrubber (4) is also connected to the tail gas heating input pipeline (701) through the wet scrubber tail gas input pipeline (403); A dehumidification water delivery pipeline (404) is connected; a dehumidification water discharge pipeline (405) is arranged below the dehumidification water delivery pipeline (404); a cooling water delivery pipeline (406) is arranged below the dehumidification water discharge pipeline (405); a secondary dehumidification water delivery pipeline (407) is connected to the middle of the wet scrubbing tower (4); a cooling water pH meter input pipeline (408) and a salinity meter input water pipeline (409) are also connected to the bottom of the wet scrubbing tower (4); a cooling water output port (410) and a cooling water drain gate (411) are also installed at the bottom of the wet scrubbing tower (4).
According to claim 8, a tail gas treatment system in a process of crushing and sorting scrapped power lithium batteries is characterized in that: the activated carbon adsorption tower (5) is connected to the tail gas output pipeline (703) of the tail gas heating exchanger through a hot air purge pipeline (501) and an activated carbon adsorption tower tail gas inlet pipeline (502); the activated carbon adsorption tower (5) is connected to the chimney (9) through an activated carbon adsorption tower tail gas output pipeline (503) and an induced draft fan (504).