Waste lithium battery pretreatment and thermal power generating unit coupling system and working method thereof

Abstract

The invention discloses a waste lithium battery pretreatment and thermal power generating unit coupling system and a working method thereof.The waste lithium battery pretreatment unit comprises a gas collecting hood, a crushing device, a drying device and a sorting device, and the crushing device, the drying device and the sorting device are arranged in the gas collecting hood; a heat absorption side outlet of the drying device is communicated with an inlet of the sorting device, a heat source is communicated with a heat release side inlet of the drying device through a drying heat source coupling module, a heat release side outlet of the drying device is communicated with a thermal power generating unit system, and an outlet of the gas collecting hood is communicated with a dry pretreatment system in the thermal power generating unit system. The system and the working method thereof can realize the treatment of the waste lithium battery, and have the characteristics of high energy utilization rate, low investment cost and strong environmental protection capability.

Description

Technical Field

[0001] The invention belongs to the technical field of recycling waste lithium batteries and relates to a waste lithium battery pretreatment and thermal power unit coupling system and a working method thereof. Background Art

[0002] With the rapid development of the new energy industry, the recycling of waste lithium-ion batteries has become a technical problem that needs to be solved urgently. At present, the dismantling and recycling of waste lithium batteries at home and abroad mainly adopts the heat treatment method. The positive active material extracted by this technology has a high purity. The method includes the process steps of crushing, drying and sorting. However, the existing technology has the following problems that need to be solved urgently:

[0003] Relatively high energy consumption: In the existing pretreatment process, the crushing and drying steps consume a lot of heat energy. Usually, special heating equipment is required, which not only causes excessive energy consumption, but also increases carbon emissions, which is contrary to the national energy conservation and emission reduction policy.

[0004] The investment cost of the production line is relatively high: the independent pretreatment system needs to be equipped with special heating equipment and exhaust gas treatment facilities, which greatly increases the investment in fixed assets and reduces the economic feasibility of the project.

[0005] Environmental pressure is high: the heat treatment process will produce harmful gases such as fluorine-containing compounds and heavy metal dust. These special pollutants are difficult to handle and the potential harm to the environment cannot be ignored.

[0006] Resource utilization efficiency needs to be improved: the existing technical solutions have not yet established an organic coupling between the recycling of waste lithium batteries and the energy system, and have failed to achieve cascade utilization and multi-level recycling of resources, resulting in waste of energy and resources.

[0007] By searching relevant patent documents at home and abroad, no technical solution has been found to organically couple the waste lithium battery pretreatment system with the thermal power unit. Therefore, there is an urgent need for an innovative waste lithium battery pretreatment method that can improve energy utilization efficiency, reduce investment costs, enhance environmental protection processing capabilities, and achieve industrial coordinated development. Summary of the invention

[0008] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a waste lithium battery pretreatment and thermal power unit coupling system and a working method thereof. The system and the working method thereof can realize the treatment of waste lithium batteries and have the characteristics of high energy utilization rate, low investment cost and strong environmental protection ability.

[0009] To achieve the above-mentioned purpose, the present invention discloses a waste lithium battery pretreatment and thermal power unit coupling system, comprising a waste lithium battery pretreatment unit, a thermal power unit system, a drying heat source coupling module and an exhaust gas treatment coupling module;

[0010] The waste lithium battery pretreatment unit comprises an air collecting hood and a crushing device, a drying device and a sorting device arranged in the air collecting hood, the outlet of the crushing device is connected to the heat absorption side inlet of the drying device, the heat absorption side outlet of the drying device is connected to the inlet of the sorting device, the heat source is connected to the heat release side inlet of the drying device through a dry heat source coupling module, the heat release side outlet of the drying device is connected to a thermal power unit system, and the outlet of the air collecting hood is connected to a dry pretreatment system in the thermal power unit system.

[0011] Furthermore, the drying heat source coupling module includes a heat source delivery pipeline and a flue gas / steam flow regulating device; the heat source is the tail flue of the boiler of the thermal power unit, the heat release side inlet of the drying device is connected to the smoke exhaust port on the tail flue of the boiler of the thermal power unit through the heat source delivery pipeline and the flue gas / steam flow regulating device, and the heat release side outlet of the drying device is connected to the flue gas environmental protection treatment facility of the thermal power unit system.

[0012] Furthermore, the drying heat source coupling module includes a heat source delivery pipeline and a flue gas / steam flow regulating device; the heat source is a steam turbine system, the heat release side inlet of the drying device is connected to the steam extraction port of the steam turbine system through the heat source delivery pipeline and the flue gas / steam flow regulating device, and the heat release side outlet of the drying device is connected to the thermal power unit heat recovery heating system in the thermal power unit system through the steam-water separation device.

[0013] Furthermore, the outlet of the gas collecting hood is connected to the inlet of the dry pretreatment system through the exhaust gas collection device and the exhaust gas delivery pipeline.

[0014] Furthermore, it also includes electrostatic precipitator, bag filter, wet desulfurization tower, wet dust collector and chimney;

[0015] The outlet of the dry pretreatment system is connected to the inlet of the wet desulfurization tower via an electrostatic precipitator and a bag filter in sequence, and the outlet of the wet desulfurization tower is connected to the chimney via a wet dust collector.

[0016] Furthermore, an online monitoring system is installed at the bottom of the chimney.

[0017] The present invention discloses a working method of a waste lithium battery pretreatment and thermal power unit coupling system, comprising the following steps:

[0018] 1) Under an inert atmosphere, the waste lithium batteries are crushed by a crushing device.

[0019] 2) using the introduced heat source to dry the crushed material in a drying device to remove the electrolyte and obtain a dried material;

[0020] 3) Use a sorting device to sort the dried material;

[0021] 4) The tail gas generated during the pretreatment process enters the dry pretreatment system.

[0022] Furthermore, the heat release side inlet of the drying device is connected to the heat source through the heat source delivery pipeline and the flue gas / steam flow regulating device, and the temperature of the heat source is adjusted to 100°C-500°C by the flue gas / steam flow regulating device.

[0023] Furthermore, the specific operation of step 5) is:

[0024] The exhaust gas generated during the pretreatment process enters the chimney through the dry pretreatment system, electrostatic precipitator, bag filter, wet desulfurization tower and wet dust collector in sequence.

[0025] Further, for ternary lithium batteries, the drying temperature of the drying device is 90 to 400°C;

[0026] For lithium iron phosphate batteries, the drying temperature of the drying device is 100-500°C;

[0027] For lithium manganese oxide batteries and lithium cobalt oxide batteries, the drying temperature of the drying device is 150-600°C.

[0028] The present invention has the following beneficial effects:

[0029] The waste lithium battery pretreatment and thermal power unit coupling system and the working method thereof described in the present invention, during specific operation, organically integrate the new energy recycling industry with the traditional energy industry, and provide a new technical path for the efficient, low-cost and environmentally friendly treatment of waste lithium batteries. Specifically, the crushed material is dried using the thermal power unit as a heat source to remove the electrolyte, and then the dried material is sorted. In addition, the tail gas generated during the drying, crushing and sorting process is sent to the dry pretreatment system of the thermal power unit system, thereby realizing the treatment of waste lithium batteries. The operation is simple, convenient and extremely practical.

[0030] Furthermore, an online monitoring system (CEMS) is installed at the bottom of the chimney to monitor the concentration of pollutants such as SO2, NOx, dust and HF in the mixed flue gas in real time. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0032] Figure 1 It is a structural diagram of the present invention;

[0033] Figure 2 This is the process diagram for high temperature flue gas heat treatment drying;

[0034] Figure 3 Process diagram for drying of steam turbine extraction preheat treatment;

[0035] Figure 4 This is the schematic diagram of exhaust gas treatment. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] In the description of the present invention, it should be understood that the terms “include” and “comprises” indicate the presence of described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or collections thereof.

[0038] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0039] It should be further understood that the term "and / or" used in the present specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present invention generally indicates that the associated objects are in an "or" relationship.

[0040] It should be understood that, although the terms first, second, third, etc. may be used to describe preset ranges, etc. in the embodiments of the present invention, these preset ranges should not be limited to these terms. These terms are only used to distinguish preset ranges from each other. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0041] The word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0042] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can usually be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0043] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0044] refer to Figure 1 , Figure 2 , Figure 3 and Figure 4 The waste lithium battery pretreatment and thermal power unit coupling system of the present invention comprises a waste lithium battery pretreatment unit, a thermal power unit system, a dry heat source coupling module and an exhaust gas treatment coupling module; the waste lithium battery pretreatment unit comprises a crushing device, a drying device and a sorting device; the dry heat source coupling module comprises a heat source transmission pipeline and a flue gas / steam flow regulating device; the exhaust gas treatment coupling module comprises a dry pretreatment system, an electrostatic precipitator, a bag filter, a wet desulfurization tower, a wet dust collector and a chimney.

[0045] The inlet of the waste lithium battery is connected with the inlet of the crushing device, the outlet of the crushing device is connected with the inlet of the heat absorption side of the drying device, the outlet of the heat absorption side of the drying device is connected with the inlet of the sorting device, and the inlet of the heat release side of the drying device is connected with the exhaust port on the tail flue of the boiler of the thermal power unit or the steam extraction port of the turbine system through the heat source transmission pipeline and the flue gas / steam flow regulating device.

[0046] Among them, when the heat release side inlet of the drying device is connected to the exhaust port on the tail flue of the boiler of the thermal power unit through the heat source conveying pipeline and the flue gas / steam flow regulating device, the heat release side outlet of the drying device is connected to the flue gas environmental protection treatment facility; when the heat release side inlet of the drying device is connected to the steam extraction port of the steam turbine system through the heat source conveying pipeline and the flue gas / steam flow regulating device, the heat release side outlet of the drying device is connected to the heat recovery heating system of the thermal power unit through the steam-water separation device;

[0047] The crushing device, drying device and sorting device are all located in the gas collecting hood. The outlet of the gas collecting hood is connected to the inlet of the dry pretreatment system via the exhaust gas collection device and the exhaust gas conveying pipeline. The outlet of the dry pretreatment system is connected to the inlet of the wet desulfurization tower via the electrostatic precipitator and the bag dust collector in turn. The outlet of the wet desulfurization tower is connected to the chimney via the wet dust collector.

[0048] refer to Figure 1 , Figure 2 , Figure 3 and Figure 4 The working method of the coupling system of waste lithium battery pretreatment and thermal power unit of the present invention comprises a waste lithium battery pretreatment unit, a thermal power unit system, a dry heat source coupling module and an exhaust gas treatment coupling module; the waste lithium battery pretreatment unit comprises a crushing device, a drying device and a sorting device; the dry heat source coupling module comprises a heat source transmission pipeline and a flue gas / steam flow regulating device; the exhaust gas treatment coupling module comprises a dry pretreatment system, an electrostatic precipitator, a bag filter, a wet desulfurization tower, a wet dust collector and a chimney.

[0049] Specifically, the working method of the waste lithium battery pretreatment and thermal power unit coupling system includes the following steps:

[0050] 1) Under an inert atmosphere (such as nitrogen), the waste lithium batteries are crushed by a crushing device (110).

[0051] 2) A heat source is introduced from a thermal power unit boiler (210) or a steam turbine system (230) through a dry heat source coupling module (300), and a flue gas / steam flow rate regulating device (310) regulates the temperature of the heat source to within a range of 100 to 500° C. according to the requirements of different types of batteries. For example, for a ternary lithium battery, the temperature is controlled within a range of 120 to 150° C.; for a lithium iron phosphate battery, the temperature is controlled within a range of 200 to 250° C.

[0052] 3) The crushed material is dried in the drying device (120) by using the introduced heat source to remove the electrolyte, thereby making full use of the waste heat resources of the thermal power unit and significantly reducing energy consumption. The dried flue gas is heated by high-temperature flue gas and enters the flue gas environmental protection treatment facility (220) of the thermal power unit; the heat source after the drying battery is heated by steam extraction from the steam turbine and then flows into the heat recovery heating system (240) of the thermal power unit after passing through the steam-water separation device (330).

[0053] 4) Using a sorting device (130) to sort the dried material to obtain different components such as positive electrode material, negative electrode material, metal shell, etc. The present invention adopts advanced sorting technology to ensure that the sorting efficiency reaches more than 95%.

[0054] 5) The tail gas generated during the pretreatment process passes through the tail gas collection device (410) and the tail gas delivery pipeline (430) and then enters the dry pretreatment system.

[0055] The specific operations of step 5) are:

[0056] 51) The tail gas enters the dry pretreatment system, and the temperature of the pretreated tail gas entering the dry pretreatment system is guaranteed to be between 80 and 100°C to improve the reaction efficiency and prevent water vapor condensation. Through a precisely controlled injection system, fine calcium carbonate particles are evenly sprayed into the tail gas discharged during the drying process. HF reacts rapidly with calcium carbonate to generate calcium fluoride and carbon dioxide. The reaction equation is: CaCO3+2HF→CaF2+H2O+CO2. The cyclone reactor design is adopted to extend the gas-solid contact time and improve the pretreatment reaction efficiency.

[0057] 52) The exhaust gas then enters the electrostatic precipitator and bag filter, using polytetrafluoroethylene (PTFE) coated filter bags with a filtration efficiency of ≥99.9%. This not only removes metal dust, but also captures calcium fluoride generated by the reaction and unreacted calcium carbonate particles. Pulse jet technology is used to regularly remove dust accumulated on the surface of the filter bags. The filtered dust contains valuable metals and calcium fluoride, which are sent to a special recovery and processing line.

[0058] 53) The tail gas then enters the wet flue gas desulfurization tower, and uses the limestone-gypsum wet flue gas desulfurization system to remove SO2 and residual HF at the same time. The removal efficiency of HF is improved by improving the spray layer design, and the slurry pH value is monitored and adjusted in real time to balance the removal efficiency of SO2 and HF.

[0059] 54) The exhaust gas then enters the wet dust collector to remove gypsum droplets and other fine particles that may be produced during the desulfurization process, further reducing the dust content in the flue gas and ensuring that ultra-low emission standards are met.

[0060] 55) The exhaust gas and flue gas finally enter the chimney of the thermal power unit. An online monitoring system (CEMS) is installed at the bottom of the chimney to monitor the concentration of pollutants such as SO2, NOx, dust and HF in the mixed flue gas in real time.

[0061] It should be noted that the treatment standard for special pollutants in tail gas during battery drying is: for Class II inorganic dust such as cobalt and nickel, ensure that its mass flow rate is less than 2.5g / h and its concentration is less than 0.5mg / m 3 , hydrogen fluoride treatment, ensuring that its mass flow rate is less than 10g / h and the concentration is less than 1mg / m 3 , ensure that the total concentration of organic matter is less than 20mg / m 3 .

[0062] The present invention can adapt to the treatment requirements of different types of waste lithium batteries. The following are examples of specific treatment solutions for several typical lithium batteries:

[0063] For example, for ternary lithium batteries (NCM): the dry heat treatment temperature is 90-400°C, and medium and low temperature heat sources are preferentially used. At the same time, the removal measures for heavy metal dust (such as cobalt and nickel) can be strengthened, and the treatment of organic solvents can be strengthened.

[0064] For example, for lithium iron phosphate batteries (LFP): the dry heat treatment temperature is 100-500°C, and medium and high temperature heat sources are preferentially used. At the same time, the treatment of fluorides can be strengthened to effectively remove HF gas.

[0065] For example, for lithium manganese oxide batteries (LMO) and lithium cobalt oxide batteries (LCO): the drying heat treatment temperature is 150-500°C, and a medium-temperature heat source can be selected to enhance the capture of manganese dust and cobalt dust.

[0066] It should be noted that the present invention has the following characteristics:

[0067] a) Innovative system integration: The present invention proposes and realizes the organic coupling between the waste lithium-ion battery pretreatment system and the thermal power unit, creating a new model for the coordinated development of new energy recycling and traditional energy industries.

[0068] b) Efficient energy utilization: The present invention realizes the cascade utilization of energy through multi-stage heat source coupling and intelligent temperature control technology, and the pre-treatment energy consumption is reduced by more than 50%.

[0069] c) Collaborative environmental protection treatment: The present invention utilizes the existing flue gas treatment system of thermal power units to collaboratively treat special pollutants, thereby increasing treatment efficiency by 30% and reducing investment costs by 40%.

[0070] d) Efficient resource recovery: The present invention adopts directional crushing and multi-stage efficient sorting technology, and the key metal recovery rate reaches more than 95%, which is significantly higher than the existing technical level.

[0071] e) Large-scale processing capacity: With the help of the infrastructure and processing capacity of thermal power plants, the annual processing capacity of a single system can reach 100,000 tons, laying the foundation for large-scale application.

[0072] f) Significant economic benefits: The present invention takes into account the reduction of energy consumption, the reduction of investment and the improvement of recovery rate, and is expected to reduce the processing cost of waste lithium-ion batteries by more than 30%.

[0073] g) Environmentally friendly production line: Through coordinated processing and ultra-low emission technology, the present invention reduces the emission of harmful substances by more than 60% compared with the existing technology, making an important contribution to the green circular economy.

[0074] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and disclosure of the invention. This application is intended to cover any variations, uses or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not disclosed by the present invention. The specification and examples are to be considered exemplary only, and the true scope and spirit of the present invention are indicated by the following claims.

[0075] It should be understood that the present invention is not limited to the exact construction that has been described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

[0076] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A waste lithium battery pretreatment and thermal power unit coupling system, characterized in that: It includes a waste lithium battery pretreatment unit, a thermal power unit system, a drying heat source coupling module and an exhaust gas treatment coupling module; The waste lithium battery pretreatment unit comprises an air collecting hood and a crushing device, a drying device and a sorting device arranged in the air collecting hood, the outlet of the crushing device is connected to the heat absorption side inlet of the drying device, the heat absorption side outlet of the drying device is connected to the inlet of the sorting device, the heat source is connected to the heat release side inlet of the drying device through a dry heat source coupling module, the heat release side outlet of the drying device is connected to a thermal power unit system, and the outlet of the air collecting hood is connected to a dry pretreatment system in the thermal power unit system.

2. The waste lithium battery pretreatment and thermal power unit coupling system according to claim 1 is characterized in that: The drying heat source coupling module includes a heat source delivery pipeline and a flue gas / steam flow regulating device; the heat source is the tail flue of the boiler of the thermal power unit, the heat release side inlet of the drying device is connected to the smoke outlet on the tail flue of the boiler of the thermal power unit through the heat source delivery pipeline and the flue gas / steam flow regulating device, and the heat release side outlet of the drying device is connected to the flue gas environmental protection treatment facility of the thermal power unit system.

3. The waste lithium battery pretreatment and thermal power unit coupling system according to claim 1 is characterized in that: The drying heat source coupling module includes a heat source delivery pipeline and a flue gas / steam flow regulating device; the heat source is a steam turbine system, the heat release side inlet of the drying device is connected to the steam extraction port of the steam turbine system through the heat source delivery pipeline and the flue gas / steam flow regulating device, and the heat release side outlet of the drying device is connected to the thermal power unit heat recovery heating system in the thermal power unit system through the steam-water separation device.

4. The waste lithium battery pretreatment and thermal power unit coupling system according to claim 1 is characterized in that: The outlet of the gas collecting hood is connected to the inlet of the dry pretreatment system through the exhaust gas collecting device and the exhaust gas conveying pipeline.

5. The waste lithium battery pretreatment and thermal power unit coupling system according to claim 1 is characterized in that: It also includes electrostatic precipitators, bag filters, wet desulfurization towers, wet dust collectors and chimneys; The outlet of the dry pretreatment system is connected to the inlet of the wet desulfurization tower via an electrostatic precipitator and a bag filter in sequence, and the outlet of the wet desulfurization tower is connected to the chimney via a wet dust collector.

6. The waste lithium battery pretreatment and thermal power unit coupling system according to claim 1 is characterized in that: An online monitoring system is installed at the bottom of the chimney.

7. A working method of the waste lithium battery pretreatment and thermal power unit coupling system according to claim 1, characterized in that: The following steps are involved: 1) In an inert atmosphere, the waste lithium batteries are crushed by a crushing device. 2) using the introduced heat source to dry the crushed material in a drying device to remove the electrolyte and obtain a dried material; 3) Use a sorting device to sort the dried material; 4) The tail gas generated during the pretreatment process enters the dry pretreatment system.

8. The working method of the waste lithium battery pretreatment and thermal power unit coupling system according to claim 7 is characterized in that: The heat release side inlet of the drying device is connected to the heat source through the heat source conveying pipeline and the flue gas / steam flow regulating device, and the temperature of the heat source is adjusted to 100°C-500°C by the flue gas / steam flow regulating device.

9. The working method of the waste lithium battery pretreatment and thermal power unit coupling system according to claim 7 is characterized in that: The specific operations of step 5) are: The exhaust gas generated during the pretreatment process enters the chimney through the dry pretreatment system, electrostatic precipitator, bag filter, wet desulfurization tower and wet dust collector in sequence.

10. The working method of the waste lithium battery pretreatment and thermal power unit coupling system according to claim 7, characterized in that: The drying heat source coupling module includes a heat source delivery pipeline and a flue gas / steam flow regulating device; the heat source is the tail flue of the boiler of the thermal power unit, the heat release side inlet of the drying device is connected to the smoke outlet on the tail flue of the boiler of the thermal power unit through the heat source delivery pipeline and the flue gas / steam flow regulating device, and the heat release side outlet of the drying device is connected to the flue gas environmental protection treatment facility of the thermal power unit system.

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