Movable waste incineration fly ash acid leaching-crushing-smoldering integrated treatment device and method

Abstract

The invention discloses a movable waste incineration fly ash acid leaching-crushing-smoldering integrated treatment device and method, which reconstructs a traditional fixed production line into a movable treatment unit conforming to road transportation specifications through a compact structure design and an innovative space compression technology and a detachable connection technology. And meanwhile, efficient connection of all working procedures is guaranteed through unified equipment pipelines and process interfaces, and fly ash acid leaching-crushing-smoldering integration is achieved. The acid leaching wastewater and the smoldering tail gas can be respectively connected into the wastewater treatment system in the incineration plant and the garbage incinerator for treatment in a hose connection manner, so that the removal of polluting gases and the like is guaranteed while the substantial equipment cost is not increased, and meanwhile, compared with a fixed treatment plant, the treatment method has the advantages that the treatment cost is reduced; the movable device can reduce the risk of secondary pollution in the fly ash transportation process, is particularly suitable for emergency treatment of sudden pollution events and multi-plant cyclic operation scenes, provides a new thought for the high-energy-consumption treatment situation in the waste field, and has considerable popularization value.

Description

Technical Field

[0001] The present invention relates to the field of harmless treatment of waste incineration fly ash, and particularly to a device and method for self-sustaining smoldering treatment of dioxins in waste incineration fly ash. Background Art

[0002] The technology of domestic waste incineration and power generation has become the mainstream technology for domestic waste disposal in China at present. Due to the enrichment of highly toxic substances such as dioxins and other persistent organic pollutants and heavy metals, fly ash has been included in the list of hazardous wastes in China (HW18). At present, the harmless treatment of fly ash faces two major dilemmas: "large fly ash output and high treatment cost" and "difficult degradation of dioxins and complex mechanism".

[0003] At present, the domestic waste incineration fly ash in China is still mainly landfilled. Due to the shortage of land resources and the limitation of the hazardous waste attribute, it is difficult for most regions to meet the fly ash landfill requirements in terms of both land and economy. At the same time, the dioxins in fly ash are difficult to remove and degrade due to their large molecular weight, high thermal stability, complex chemical structure, trace-level content and other characteristics, which has become one of the difficulties in almost all fly ash harmless treatment and resource utilization technologies. In view of the above dilemmas and requirements, it is urgent to solve the problems of devices and methods that can continuously and large-scale treat fly ash, while saving energy, reducing costs and reducing pollution.

[0004] According to the requirements of heavy metal content, the pretreatment method is essential. A movable acid leaching tank can effectively reduce the heavy metal and chlorine content in fly ash, and at the same time contribute to the degradation of dioxins to a certain extent. According to the characteristics of dioxins, both high-temperature and low-temperature heat treatment methods have certain disadvantages. Adopting the smoldering combustion method (hereinafter referred to as the smoldering technology) can achieve the purpose of volume reduction and degradation of organic pollutants of the treatment object. The smoldering technology is a slow, flameless heterogeneous oxidation exothermic reaction process occurring on the surface of porous media. Self-sustaining smoldering means that except for the heat supplied by the outside world during the reaction startup stage, all the heat required for subsequent treatment is provided by the treatment material itself, which can significantly reduce the energy consumption cost. At the same time, the smoldering reaction area and the generated tail gas have a slightly reducing atmosphere, which can inhibit the regeneration of dioxins and play a role in reducing and detoxifying the high-valent and highly toxic heavy metals in fly ash. Using a vertical smoldering furnace to treat the acid-leached fly ash and cooperating with a movable acid leaching tank can improve the flexibility of the device and reduce the device cost. To prevent secondary pollution problems, the acid leaching wastewater can be directly connected to the wastewater treatment system of the incineration plant, and the smoldering tail gas can be used as the primary air in the incinerator for treatment in the incinerator, which significantly improves the economy of fly ash treatment. The above steps can be carried out continuously to effectively control dioxins and reduce costs and increase efficiency.

[0005] The idea of continuous smoldering treatment after acid leaching, a fly ash harmless treatment technology that can efficiently and thoroughly remove dioxins and significantly reduce energy consumption, can provide new ideas for solving the key bottleneck problems in fly ash treatment in the current waste incineration industry. Summary of the Invention

[0006] The object of the present invention is to provide a movable integrated disposal device and method for acid leaching - crushing - smoldering of waste incineration fly ash in view of the deficiencies of the prior art.

[0007] The object of the present invention is achieved by the following technical solutions: A movable integrated disposal device for acid leaching - crushing - smoldering of waste incineration fly ash includes an integrated disposal unit for fly ash acid leaching - drying - crushing, a mixing and conveying unit for fly ash particles and biomass fuel, a smoldering reaction unit, a blower and induced draft unit, a waste treatment unit, a monitoring unit and a control unit;

[0008] The integrated disposal unit for fly ash acid leaching - drying - crushing adopts a three - stage series layout, spatially optimizing and integrating acid leaching equipment, drying equipment and crushing equipment, and integrating them coaxially in a reinforced tank - type container. According to the heavy metal content, particle size and water content requirements of fly ash, continuous acid leaching, drying, crushing and screening of fly ash are carried out to reduce the water content of fly ash to 10% - 15% and control the particle size distribution of fly ash particles within 4 - 6 mm, and then it is transported to the mixing and conveying unit for fly ash particles and biomass fuel;

[0009] The mixing and conveying unit for fly ash particles and biomass fuel realizes rapid coupling and migration with the front - end treatment unit and the smoldering unit through an integrated compact design and an adaptive connection structure. Inside, it integrates a spiral mixer, a fly ash storage bin and a biomass fuel metering bin. According to the type and calorific value of the biomass used and the required self - sustaining smoldering conditions, the addition ratio of biomass fuel is regulated through a V - type feeding trough with a weighing sensor and then transported to the smoldering reaction unit;

[0010] The smoldering reaction unit is used to regulate the loading, unloading and ignition processes. It adopts a vertical smoldering furnace design. By adjusting the opening degrees of the bottom baffles of the fly ash storage bin, the biomass fuel bin and the vertical smoldering furnace through the control panel, the balance of the feeding amount and the discharging amount is regulated to maintain the stability of the smoldering front for continuous disposal of fly ash. The smoldering reaction temperature of the material is monitored in real time through a thermocouple, and the smoldering temperature is adjusted to be maintained at 400 - 850 °C to achieve the desorption or degradation of dioxins in fly ash; at the same time, the reducing atmosphere in the tail gas helps to inhibit the regeneration of dioxins and plays a reducing role on high - valence heavy metals, realizing continuous disposal of fly ash. The fly ash after smoldering treatment can be directly transported for landfill or other treatments;

[0011] The fly ash acid leaching-drying-crushing integrated treatment unit, the fly ash particle and biomass fuel mixing and conveying unit, and the smoldering reaction unit adopt standardized connection methods. The pipelines are designed with triple composite bellows, pneumatic sealing rings are set at both ends of the interfaces, the pipe body is divided into standard sections and compensation sections according to functions, and the sections are connected by quick-release flanges. A single-section pipeline can be compressed to 30% of its original length for transportation. Rotary snap flanges are installed at the interfaces between the equipment and the pipelines. When docking, the flanges are rotated and locked by electromagnetic induction triggering. The bellows extend to the set length under the drive of a servo motor, and the pneumatic sealing rings are inflated to achieve double sealing, realizing rapid assembly, connection, and disassembly between various equipment and process flows;

[0012] The waste treatment unit is used for the post-treatment of acid leaching reaction and smoldering reaction. The acid leaching wastewater and smoldering tail gas are respectively connected to the wastewater treatment system in the incineration plant and the treatment in the waste incinerator through hose connection methods, without the need to add additional post-treatment facilities, reducing costs.

[0013] Furthermore, the fly ash acid leaching-drying-crushing integrated treatment device is integrated into a reinforced tank-type container body in a coaxial manner. The equipment layer adopts a three-dimensional modular layout. The upper layer is the acid leaching reaction area, the middle layer is arranged with drying units, and the bottom layer is installed with crushing equipment.

[0014] Furthermore, when continuously leaching, drying, crushing, and screening fly ash, starting from the acid leaching reaction tank, the fly ash after acid leaching is connected to the feed bin of the disk dryer through a screw conveyor, and an airtight quick-connect flange is set at the connection section to ensure that corrosive liquids do not leak; a vibrating screening mechanism is equipped at the outlet end of the drying equipment. The fly ash after drying enters the feed inlet of the jaw crusher through a diversion trough. The diversion trough and the crushing cavity adopt a hinged buffer interface, which can offset the structural deformation during equipment movement; a drum-type screening machine is equipped at the outlet section of the jaw crusher to send the fly ash particles meeting the particle size requirements into the screw feeder.

[0015] Furthermore, the fly ash storage bin and the biomass fuel bin in the fly ash particle and biomass fuel mixing and conveying device are arranged side by side on the upper layer of the box body. A two-way spiral stirring shaft is set in the mixing cavity, and the blades adopt a detachable fan-shaped design, which is convenient for disassembly and storage during transportation.

[0016] Furthermore, the smoldering reaction device is placed on the lower layer of the double-layer container-type frame and is docked with the upper-layer fly ash particle and biomass fuel mixing and conveying unit through a quick-insert type compressed air interface. The conveying pipeline adopts a segmented nested structure, and when docking, the flanges are rotated and locked by electromagnetic induction triggering to realize the transfer of materials between units.

[0017] Furthermore, the smoldering reaction unit includes an air diffuser. When the first-stage thermocouple at the bottom end of the vertical smoldering furnace reaches the ignition temperature, start the blower to send air to the air diffuser of the vertical smoldering furnace to play a role in evenly distributing the air flow.

[0018] Furthermore, heavy-duty universal wheel sets and hydraulic lifting brackets are provided at each equipment layer and the bottom of the tank body, and an automatic locking device is set at the key connection parts to provide stable support. The tank body size strictly follows the ISO standard container transportation specifications.

[0019] Furthermore, the standardized connection method adopts a triple composite bellows design. The inner layer is a PTFE corrosion-resistant lining tube, the middle layer is a stainless steel spiral reinforcing rib, the outer layer is covered with a silicone rubber buffer layer, and pneumatic sealing rings are set at both ends. Through pneumatic sealing and flange rotation and buckling actions, rapid assembly and connection between various equipment and technological processes are realized.

[0020] Furthermore, the fly ash solid residue after smoldering treatment is stacked in the factory and transported out together with the bottom slag after passing the inspection, and can be treated as building materials raw materials.

[0021] Furthermore, the acid leaching wastewater and smoldering tail gas can be respectively connected to the wastewater treatment system in the incineration plant and used as the primary air of the waste incinerator through flexible connection hoses. The hose connection method is very flexible and can adapt to the movement and displacement between different equipment.

[0022] On the other hand, the present invention also provides a mobile waste incineration fly ash acid leaching-crushing-smoldering integrated disposal method. The specific steps of the method are as follows:

[0023] (1) Integrate the fly ash acid leaching-drying-crushing integrated disposal unit, the fly ash particle and biomass fuel mixing and conveying unit, and the smoldering reaction unit into two reinforced tank-type containers. Through a compact structure design and detachable connection technology, reconstruct the traditional fixed production line into a mobile treatment unit that meets the road transportation specifications, while ensuring the efficient connection of each process;

[0024] (2) Adopt a standardized connection method between the fly ash acid leaching-drying-crushing integrated disposal device, the fly ash particle and biomass fuel mixing and conveying device, and the smoldering reaction device. The pipeline segments are connected by quick-release flanges, and are combined, adjusted and disassembled as needed to adapt to different spaces. Rotary snap flanges are installed at the interfaces between each device and the pipeline. When docking, the flange rotation and locking are triggered by electromagnetic induction. The bellows extends to the set length under the drive of the servo motor, and the pneumatic sealing ring is inflated to achieve double sealing, realizing rapid assembly, connection and disassembly between various equipment and technological processes;

[0025] (3) According to the heavy metal content requirements and fly ash particle size requirements, wash, acid leach, oxidize, dry, crush and screen the fly ash successively to leach the heavy metals on the fly ash washing residue, and obtain fly ash particles with low heavy metal content and meeting the smoldering particle size requirements. The wastewater after acid leaching treatment can be connected to the wastewater treatment system in the incineration plant for treatment through a hose connection method.

[0026] (3) According to the smoldering self-sustaining conditions and the types and calorific values of the biomass used, fly ash particles with a particle size distribution of 4-6 mm and biomass fuel are proportionally blended to achieve co-disposal;

[0027] (4) Regulate the loading, unloading and ignition processes of the smoldering reaction. As a porous medium in the smoldering reaction, fly ash not only provides the required activation reaction surface for the smoldering of biomass fuel, but also can store the heat generated by smoldering and ignite the downstream materials. Adjusting the loading and unloading interval time can maintain the stability of the smoldering front, and thus achieve the self-sustainability and continuous disposal of the smoldering disposal process;

[0028] (5) The peak temperature of smoldering is maintained at 400-850 °C to achieve the desorption or degradation of dioxins in fly ash and biomass particles; at the same time, reducing atmospheres such as CO in the tail gas helps to inhibit the re-formation of dioxins;

[0029] (6) The tail gas of the smoldering reaction is sent into the incinerator of the waste incineration plant through a hose under the action of a induced draft fan, and is treated in the incinerator as the primary air of the incinerator, without the need to add additional post-treatment equipment costs.

[0030] The beneficial effects of the present invention are as follows:

[0031] 1. This integrated device has achieved a breakthrough in the motorization transformation of hazardous waste treatment equipment. Through innovative space compression technology (the equipment spacing is controlled at 150-300 mm) and an adaptive connection system, the entire device can be disassembled, shipped within 8 hours, and quickly resume production after arriving at a new site. Compared with fixed treatment plants, this mobile device can reduce the risk of secondary pollution during the transportation of fly ash, and is especially suitable for the emergency treatment of sudden pollution incidents and the multi-plant cyclic operation scenario.

[0032] 2. The device is integrated into a reinforced tank-type container. The tank size strictly follows the ISO standard container transportation specifications. Through a compact structure design and detachable connection technology, the traditional fixed production line is reconstructed into a mobile treatment unit that meets the road transportation specifications, while ensuring the efficient connection of each process.

[0033] 3. Except for the start-up stage, all the heat in the smoldering disposal process is provided by the biomass fuel blended between the porous media through oxidation exothermic reaction, ensuring the low energy consumption and low cost of the smoldering disposal process, and the biomass waste does not increase the substantial carbon emissions while being co-disposed. Compared with other technologies, it has obvious carbon emission reduction benefits. In addition, the smoldering reaction chamber adopts a vertical smoldering furnace, which is flexible and movable. By regulating the material loading and unloading interval, the smoldering reaction is ensured to be continuous, the smoldering front is stable, and the stable emission of tail gas is maintained.

[0034] 4. The wastewater generated during the acid leaching treatment process is connected to the wastewater treatment system of the waste incineration plant through a flexible connection hose, eliminating the need to add additional wastewater treatment equipment. The smoldering tail gas is collected by an induced draft fan and sent to the waste incinerator through a flexible connection hose under the action of the induced draft fan. It serves as the primary air of the incinerator and is treated therein, ensuring the removal of polluting gases and the like without increasing the substantial equipment cost, and ensuring the cleanliness and safety of the tail gas.

[0035] 5. Standardized connection methods are adopted between the components of each treatment unit of the system. The pipeline is designed with a triple composite corrugated pipe. Pneumatic sealing rings are set at both ends of the interface. The pipe body is divided into a standard section and a compensation section according to functions. The sections are connected by quick-release flanges and can be combined, adjusted, and disassembled as needed. A single-section pipe can be compressed to 30% of its original length for transportation. Rotary snap flanges are installed at the interfaces between the equipment and the pipeline, and they act together with the pneumatic seal during docking to achieve double sealing. The daily treatment capacity of the equipment is about 3 - 8t, and it can be transported between various waste incineration plants and installed, debugged, and operated on-site, reducing the equipment manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0037] Figure 1 Schematic diagram of a movable integrated disposal device for acid leaching - crushing - smoldering of waste incineration fly ash of the present invention;

[0038] Reference numerals: 1. Three - layer tank container; 2. Acid leaching reaction tank; 3. Screw conveyor; 4. Composite corrugated pipeline and rotary snap - type flange; 5. Disk dryer and its vibrating screening mechanism; 6. Hinge interface; 7. Jaw crusher; 8. Drum sieve; 9. Conveyor belt; 10. Screw feeder; 11. Integrated disposal device for acid leaching - drying - crushing of fly ash; 12. Biomass fuel metering bin; 13. Fly ash storage bin; 14. V - shaped feeding trough with weighing sensor; 15. Screw mixer; 16. Thermocouple; 17. Unsmoldered particles; 18. Vertical smoldering furnace; 19. Control panel; 20. Heating plate; 21. Ignition device controller; 22. Air diffuser; 23. Bottom slag after smoldering treatment; 24. Discharge port baffle; 25. Double - layer tank container; 26. Flow controller; 27. Blower; 28. Hydraulic lifting device and universal wheel set; 29. Induced draft fan DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] To clarify the implementation objectives, technical solutions and advantages of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several variations and improvements can be made, which are also regarded as falling within the protection scope of the present invention.

[0040] Such as Figure 1As shown in the figure, the present invention provides a mobile integrated disposal device for acid leaching-crushing-slow combustion of waste incineration fly ash. Using fly ash as a porous medium and biomass fuels such as waste wood chips and rice husks as the energy source, after introducing external energy and air to ignite, a slow combustion flameless oxidation exothermic reaction occurs to achieve the desorption or degradation of dioxins in fly ash and biomass particles. Before disposal, align the container body through the bottom layer heavy-duty universal wheel set and hydraulic lifting bracket of the tank body, and set an automatic locking device at the key connection parts to provide stable support; the components of each treatment unit in the integrated system device are connected by triple composite bellows, with pneumatic sealing rings set at both ends. The pipe body is divided into a standard section and a compensation section according to functions, and the sections are connected by quick-release flanges, which can be combined, adjusted, and disassembled as needed; a rotary snap flange is installed at the interface between the equipment and the pipeline. When docking, the flange rotates and locks through electromagnetic induction. The bellows extends to the set length under the drive of the servo motor, and the pneumatic sealing ring inflates to achieve double sealing, realizing rapid assembly, connection, and disassembly between each equipment and process flow; before the slow combustion reaction, the fly ash needs to be washed, acid leached, and oxidized first to leach out the heavy metals on the original fly ash, and then the fly ash slurry is continuously filtered, dried, crushed, and screened to prepare fly ash particles with a particle size distribution of 4-6 mm. According to the type and calorific value of the biomass used and the required slow combustion self-sustaining conditions, finely adjust the addition ratio of fly ash and biomass fuel, mix and homogenize them, and then transport them to the slow combustion reaction unit. During the slow combustion reaction process, the fly ash particles serve as a porous medium to provide the activation reaction surface required for the slow combustion reaction, and can store heat, keep warm, and transfer heat to ignite the downstream area. The slow combustion reaction temperature of the material is monitored in real time by the thermocouple built in the vertical slow combustion furnace, and the peak temperature is maintained at 400-850 °C. The loading and unloading are regulated by adjusting the opening and closing degrees of the baffle plates of the feed hopper and the discharge port to maintain the stability of the slow combustion front, and the ignition and other processes are regulated to achieve slow combustion self-sustaining; in addition, the peak temperature area is in a slightly hypoxic state, and there is a reducing atmosphere such as CO in the tail gas, which can inhibit the reformation of dioxins. The wastewater generated during the acid leaching disposal of fly ash is directly connected to the wastewater treatment system of the incineration plant through a flexible connection hose; the flue gas from the slow combustion reaction is connected to the waste incinerator through a flexible hose under the action of the induced draft fan and serves as the primary air of the incinerator and is treated therein. This solution can achieve low-carbon and efficient removal of heavy metals and dioxins in fly ash, with low disposal energy consumption. Through the innovative space compression technology (the equipment spacing is controlled at 150-300 mm) and the adaptive connection system, the whole set of system is suitable for the emergency treatment of sudden pollution incidents and the multi-plant cyclic operation scenario, reducing the risk of secondary pollution during the fly ash transportation process.

[0041] The mobile integrated disposal device for acid leaching-crushing-slow combustion of waste incineration fly ash provided by the present invention includes an integrated disposal unit for acid leaching-drying-crushing of fly ash, a mixing and conveying unit for fly ash particles and biomass fuel, a slow combustion reaction unit, a forced draft and induced draft unit, a waste treatment unit, a monitoring unit, and a control unit.

[0042] The integrated disposal unit for fly ash acid leaching-drying-crushing includes an acid leaching reaction tank 2, a screw conveyor 3, a composite corrugated pipe 4, a disk dryer and its vibrating screening mechanism 5, a jaw crusher 7, a drum sieve 8. The acid leaching reaction tank 2, the disk dryer 5 and the jaw crusher 7 are integrated coaxially in a three-layer reinforced container-type tank body 1. The upper layer is the acid leaching reaction area, the middle layer is arranged with a drying unit, and the bottom layer is embedded with crushing equipment. Before disposal, the bottom discharge port of the acid leaching reaction tank 2 is connected to the feed bin of the disk dryer 5 through the screw conveyor 3, and the composite corrugated pipe 4 is used in the connection section. When docking, the adsorption flange rotates and locks to achieve material transmission, ensuring that corrosive liquids do not leak out; the diversion groove at the outlet end of the dryer 5 and the jaw crusher adopt a hinged buffer interface 6 to offset the structural deformation during equipment movement. During disposal, starting from the acid leaching reaction tank 2, according to the heavy metal content, particle size and water content requirements of the fly ash, continuous acid leaching, drying and crushing treatments are carried out on the fly ash to reduce the water content of the fly ash to 10%-15%. A drum sieve 8 is equipped at the outlet section of the jaw crusher 7 to control the particle size distribution of the fly ash particles within 4-6 mm. The fly ash particles meeting the particle size requirements are sent into the screw feeder 10 and transported to the fly ash particle and biomass fuel mixing and conveying unit.

[0043] The fly ash particle and biomass fuel mixing and conveying unit includes a biomass fuel metering bin 12, a fly ash storage bin 13, a V-shaped guiding trough 14 with a weighing sensor and a screw mixer 15. Through an integrated compact design and an adaptive connection structure, the biomass fuel metering bin 12, the fly ash storage bin 13 and the screw mixer 15 are integrated on the upper layer of the container body. The biomass fuel bin 12 and the fly ash storage bin 13 are arranged side by side on the upper layer of the container body, and their bottoms are connected through the V-shaped guiding trough 14 with a weighing sensor to achieve precise proportioning of fly ash and fuel and send them into the screw mixer 15. A two-way spiral stirring shaft is arranged in the mixing cavity. According to the requirements of the self-sustaining condition of smoldering and the position of the appropriate smoldering front, the fly ash and biomass fuel mixed particles are batch-fed through the composite corrugated pipe to the smoldering reaction unit for smoldering treatment.

[0044] The smoldering reaction unit includes a thermocouple 16, a vertical smoldering furnace 18, a control panel 19, a heating plate 20, an ignition device controller 21, and an air diffuser 22 placed in the lower layer of the double-layer container-type frame. Before feeding, the vertical smoldering furnace is docked with the upper-layer fly ash particle and biomass fuel mixing and conveying unit through the adsorption flange 4. The conveying pipeline adopts a composite corrugated pipe nested structure 4. When docking, the adsorption flange triggers rotation and locking through electromagnetic induction to realize the transfer of materials between units. When feeding, the homogeneous materials are conveyed to the vertical smoldering furnace 18 through a screw mixer until the mixing materials fill the vertical smoldering furnace and then the feeding stops. After the feeding is completed, the ignition device 21 is turned on to continuously preheat the bottom materials near the electric heating plate 20. The materials are ignited under the heating of the heating plate 20. When the first-stage thermocouple at the bottom of the materials reaches the ignition temperature, the blower 27 of the air supply unit is started to introduce air into the vertical smoldering furnace 18 from the bottom, and the air diffuser 22 installed at the bottom of the smoldering furnace and the gas mass flow controller 26 are used to form a uniform air flow. When the first-stage thermocouple reaches the peak temperature, the bottom ignition device is turned off and self-sustaining smoldering begins. When the smoldering front propagates to the approximate center position of the smoldering furnace, the centralized control panel 19 is used to adjust the opening degree or opening and closing interval of the fly ash storage bin, the biomass fuel bin, and the baffle 24 at the bottom of the vertical smoldering furnace, control the continuous entry of the mixed materials into the vertical smoldering furnace 18, open the baffle 24 of the slag discharge port to continuously discharge the smoldering residues, achieve the balance of the feeding amount and the discharging amount, maintain the smoldering surface at a fixed height to realize the continuous disposal of fly ash and the continuous operation of smoldering treatment, and improve the treatment efficiency of dioxins in fly ash. The tail gas generated during the smoldering process is conveyed to the waste incinerator through a flexible connection hose under the action of the induced draft fan 29 for primary air treatment.

[0045] Heavy-duty universal wheel sets and hydraulic lifting brackets 28 are installed at the bottom layer of the container tank body. During operation, the legs touch the ground to lift the position, and at the same time, automatic locking devices are set at key connection parts to provide stable support. The tank body size strictly follows the ISO standard container transportation specifications. Through a compact structure design and detachable connection technology, the traditional fixed production line is reconstructed into a movable treatment unit that meets the road transportation specifications, while ensuring the efficient connection of each process.

[0046] The composite corrugated pipe 4 adopts a triple composite corrugated pipe design. The inner layer is a PTFE corrosion-resistant lining pipe, the middle layer is a stainless steel spiral reinforcing rib, the outer layer is covered with a silicone rubber buffer layer, and pneumatic sealing rings are set at both ends of the interface. When connecting between various treatment processes, the corrugated pipe extends to the set length under the drive of the servo motor, and the pneumatic sealing ring inflates and expands together with the flange rotation and buckling action to achieve double sealing. When disassembling, the pneumatic sealing ring of the material channel exhausts and contracts, the rotation buckle is unlocked reversely, and the corrugated pipe automatically retracts through the built-in spring retracting mechanism, realizing the rapid assembly, connection, and disassembly between various equipment and process flows.

[0047] The vertical smoldering furnace 18 has a height of 1.5 m - 2 m, an inner diameter of 1.2 m, and is equipped with a daily processing capacity of approximately 3 - 8 t. The amount of flue gas generated by the smoldering reaction is approximately 300 - 500 Nm 3 / h.

[0048] The smoldering treatment unit further includes a temperature monitor and an automated control system. The temperature monitor monitors the temperature of the thermocouples in the device in real time and feeds back the monitored data to the automated control system to achieve automatic regulation of the power system. In special cases, when the peak temperature of a non-final thermocouple in a smoldering reaction cylinder is 100 °C lower than the preset peak temperature, the ignition device 21 is automatically activated, and the heating plate operates to supplement heat to ensure the smooth completion of the smoldering treatment of the mixed materials.

[0049] On the other hand, corresponding to the foregoing embodiment of a mobile waste incineration fly ash acid leaching - crushing - smoldering integrated treatment device, this article also provides a method for waste incineration fly ash acid leaching - crushing - smoldering integrated treatment. The specific steps of this method are as follows:

[0050] The raw fly ash first undergoes a water washing and oxidation reaction with sulfuric acid and water to remove chlorides, eliminate the chlorine element required for the regeneration of dioxins in subsequent treatment, and leach out heavy metals on the fly ash water washing residue, thereby obtaining a fly ash slurry with a low heavy metal content. The wastewater from the acid leaching process is connected to the wastewater treatment system of the incineration plant. The fly ash with a low heavy metal content after acid leaching is first dried and vibration - sieved in a filter, and then sent to a crusher for crushing treatment and sieving again. The fly ash with a particle size meeting the requirements is mixed with biomass waste. Subsequently, the above - mentioned fly ash particles and biomass fuel are blended in proportion and adjusted to be visually uniform with an electric mixer. The blending ratio of the biomass fuel can be 6 - 15% by mass fraction, and the specific blending ratio is adjusted according to the calorific value of the biomass waste and the preset smoldering peak temperature. After mixing and homogenizing, the above - mentioned mixed materials are sent into the vertical smoldering furnace. After the materials fill the vertical smoldering furnace, the feeding ends, and the resistance heating plate located at the bottom of the materials is started for heating. Subsequently, the air blower is started and the heating plate is turned off according to the temperature feedback of each stage of thermocouples. Specifically, when the temperature of the first - stage thermocouple reaches the ignition temperature, the air blower is turned on, and air is sent into the furnace from the bottom of the smoldering furnace. When the first - stage thermocouple reaches the peak temperature, the heating plate is turned off. Then, the upper - layer materials in the smoldering furnace rely on the heat stored in the internal materials for subsequent self - sustaining smoldering chain reactions. When the smoldering front front propagates to the approximate center position of the smoldering furnace, the mixed materials are controlled to continuously enter the smoldering reactor, and at the same time, the slag discharge port baffle located at the bottom of the smoldering furnace is opened to continuously discharge the smoldering residues, realizing the continuous operation of the smoldering treatment. The position of the smoldering reaction zone can be adjusted by controlling the degree or opening - closing interval of the feed bin and the discharge port baffle. The tail gas generated during the smoldering process is transported to the waste incineration furnace through an induced draft fan for primary air treatment.

[0051] The present invention has carried out research on the technology of co-disposing municipal solid waste incineration fly ash in the sintering process. When the fly ash addition ratio is 0.26%, the emission concentration of dioxin before washing is 4.700 ng I-TEQ / Nm 3 , while it is reduced to 3.11 ng I-TEQ / Nm after washing 3 ; when the fly ash addition ratio increases to 1%, the dioxin concentration increases accordingly, being 5.709 and 3.738 ng I-TEQ / Nm before and after washing respectively 3 . The comparison shows that washing can reduce the concentration of dioxin generated during the sintering process of fly ash. The reduction amplitudes under the three working conditions are 13% (addition ratio 100%), 34% (addition ratio 0.26%), and 35% (addition ratio 1%) respectively. The above treatment effects show that washing and acid leaching of fly ash can achieve the effect of reducing the dioxin generation concentration

[0052] The present invention has carried out research on the smoldering treatment technology of dioxin in municipal solid waste incineration fly ash. By adding 20% of waste wood chips, the maximum peak temperature of the smoldering of the mixed material can reach 1087°C. The lowest energy density threshold for the self-sustaining reaction of smoldering is about 0.68 MJ / kg of the material, and the energy consumption is much lower than the requirements of the low-temperature thermal decomposition technology. Before the smoldering treatment, the average value of the dioxin toxicity equivalent concentration in the mixed material is 356 ng TEQ / kg, and after the smoldering treatment, it is all lower than 10 ng TEQ / kg, meeting the requirement that the dioxin toxicity equivalent concentration is lower than 50 ng TEQ / kg. The treatment rate of the dioxin toxicity equivalent concentration is all above 95%. The comparison shows that the total concentration and toxicity equivalent concentration of dioxin in the fly ash particles are reduced by 89.7% and 92% respectively after smoldering. The above treatment effects confirm the technical feasibility of removing dioxin from fly ash by smoldering treatment

[0053] Analysis of the fingerprint distribution characteristics of 17 2,3,7,8-PCDD / Fs toxic dioxin homologues in the gas and solid phases before and after the smoldering treatment shows that after the smoldering treatment, the high-chlorinated dioxins in the solid phase decrease, and the proportion of low-chlorinated dioxins increases, indicating that dioxin may have undergone a degradation reaction from high-chlorinated to low-chlorinated during the smoldering treatment

[0054] The above is only the implementation mode of the present invention for patent, and it is not used to limit the present invention for patent. For those skilled in the art, various changes and modifications can be made to the present invention for patent. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention for patent shall be included within the scope of the claims of the present invention for patent

Claims

1. A mobile waste incineration fly ash acid leaching-crushing-smoldering integrated treatment device, characterized in that: The device includes a fly ash acid leaching-drying-crushing integrated disposal unit, a fly ash particle and biomass fuel mixing and conveying unit, a smoldering reaction unit and a waste treatment unit; The fly ash acid leaching-drying-crushing integrated disposal unit adopts a three-stage series layout, integrating the acid leaching treatment equipment, drying equipment and crushing equipment in a coaxial manner in a reinforced tank container; The fly ash particle and biomass fuel mixing and conveying unit is internally integrated with a spiral mixer, a fly ash storage bin, and a biomass fuel metering bin, and the fly ash and biomass fuel mixed particles are conveyed in batches through a composite bellows to the smoldering reaction unit for smoldering treatment; The smoldering reaction unit is placed in the lower layer of the reinforced tank container body, and adopts a vertical smoldering furnace design. The fly ash storage bin, biomass fuel bin and the baffle opening at the bottom of the vertical smoldering furnace are adjusted through the control panel to control the balance of feed and discharge, maintain the stability of the smoldering front to continuously dispose of fly ash, and monitor the smoldering reaction temperature of the material in real time through the thermocouple and adjust it; The pipelines of the fly ash acid leaching-drying-crushing integrated disposal unit, the fly ash particle and biomass fuel mixing and conveying unit, and the smoldering reaction unit adopt a triple composite bellows design, with pneumatic sealing rings set at the interfaces at both ends, and a rotating snap-on flange installed at the interface between the equipment and the pipeline. When docking, the flange is rotated and locked by electromagnetic induction triggering. The bellows is extended to a set length under the drive of a servo motor, and the pneumatic sealing ring is inflated to achieve double sealing; The waste treatment unit is used for post-treatment of acid leaching reaction and smoldering reaction. The acid leaching wastewater and smoldering tail gas are respectively connected to the wastewater treatment system in the incineration plant and the garbage incinerator for treatment through hose connection.

2. The movable waste incineration fly ash acid leaching-crushing-smoldering integrated treatment device according to claim 1 is characterized in that: The fly ash acid leaching-drying-crushing integrated disposal unit equipment layer adopts a three-dimensional modular layout, the upper layer is the acid leaching reaction zone, the middle layer is arranged with the drying unit, and the bottom layer is embedded with the crushing equipment. The acid leaching reaction tank is used as the starting point, and its bottom discharge port is connected to the feed bin of the disc dryer through a screw conveyor, and an airtight quick-connect flange is provided in the connecting section to ensure that the corrosive liquid does not leak out; the outlet end of the drying equipment is equipped with a vibrating screening mechanism, and the dried fly ash enters the feed port of the jaw crusher through the guide groove. The guide groove and the crushing cavity adopt an articulated buffer interface to offset the structural deformation when the equipment moves; the outlet section of the jaw crusher is equipped with a drum screening machine to feed the fly ash particles that meet the particle size requirements into the spiral feeder; each equipment layer and the bottom of the tank body are provided with a heavy-duty universal wheel set and a hydraulic lifting bracket, and an automatic locking device is provided at the key connection position to provide stable support.

3. The movable waste incineration fly ash acid leaching-crushing-smoldering integrated treatment device according to claim 1 is characterized in that: According to the requirements of fly ash heavy metal content, particle size and moisture content, the fly ash is continuously treated with acid leaching, drying, crushing and screening to reduce the moisture content of the fly ash to 10%-15% and control the particle size distribution of the fly ash to 4-6 mm.

4. The movable waste incineration fly ash acid leaching-crushing-smoldering integrated treatment device according to claim 1 is characterized in that: The fly ash storage silo and the biomass fuel silo are arranged side by side on the upper layer of the tank container. The bottom of the two are connected by a V-shaped material guide trough with a weighing sensor. A bidirectional spiral stirring shaft is set in the mixing chamber, and the blades adopt a detachable fan-shaped design. A hydraulic lifting bracket is configured at the bottom of each equipment. During operation, the legs touch the ground to lift and lock the position.

5. The movable waste incineration fly ash acid leaching-crushing-smoldering integrated treatment device according to claim 4 is characterized in that: According to the type and calorific value of the biomass used and the required smoldering self-sustaining conditions, the biomass fuel addition ratio is regulated and mixed homogeneously through a V-shaped material guide trough with a weighing sensor. Then, according to the smoldering self-sustaining conditions and the requirements for the appropriate smoldering front position, it is transported to the smoldering reaction unit in batches through a composite bellows for smoldering treatment.

6. The movable waste incineration fly ash acid leaching-crushing-smoldering integrated treatment device according to claim 1 is characterized in that: The smoldering reaction unit is connected to the upper fly ash particles and biomass fuel mixing and conveying unit through an adsorption flange. The conveying pipeline adopts a composite bellows nested structure. When docking, the flange is rotated and locked by electromagnetic induction to achieve material transmission between units. The process parameters are adjusted using a centralized control panel. The smoldering temperature is maintained at 400-850°C to achieve desorption or degradation of dioxins in the fly ash. At the same time, the reducing atmosphere in the tail gas inhibits the regeneration of dioxins and reduces heavy metals. The fly ash after smoldering treatment is directly transported for landfill or other treatment.

7. The movable waste incineration fly ash acid leaching-crushing-smoldering integrated treatment device according to claim 1 is characterized in that: The smoldering reaction unit includes an air diffuser. When the first-stage thermocouple at the bottom of the vertical smoldering furnace reaches the ignition temperature, the blower is started to transport air to the air diffuser of the vertical smoldering furnace to achieve a uniform airflow.

8. The movable waste incineration fly ash acid leaching-crushing-smoldering integrated treatment device according to claim 1 is characterized in that: The fly ash acid leaching-drying-crushing integrated disposal unit, the fly ash particle and biomass fuel mixing and conveying unit, and the smoldering reaction unit are integrated in two reinforced tank containers. The tank size complies with the ISO standard container transportation specifications. The pipelines between the equipment adopt a standardized connection method and a triple composite bellows design. The inner layer is a PTFE corrosion-resistant liner, the middle layer is a stainless steel spiral reinforcement rib, the outer layer is covered with a silicone rubber buffer layer, and pneumatic sealing rings are arranged at the interfaces at both ends. When connecting between the various treatment processes, the flange adsorption triggers the rotating buckle action, and the bellows is extended to the set length under the drive of the servo motor, and the pneumatic sealing ring is inflated to achieve double sealing. When disassembling, the pneumatic sealing ring of the material channel is exhausted and contracted, and the rotating buckle is unlocked in the reverse direction, and the bellows is automatically retracted by the built-in spring winding mechanism. The pipe body is divided into a standard section and a compensation section according to its function, and the sections are connected by quick-release flanges. The single-section pipeline is compressed to 30% of the original length for transportation.

9. A movable waste incineration fly ash acid leaching-crushing-smoldering integrated treatment method based on the device according to any one of claims 1 to 8, characterized in that: The specific steps of this method are: (1) Integrate the fly ash acid leaching-drying-crushing integrated disposal unit, the fly ash particle and biomass fuel mixing and transportation unit, and the smoldering reaction unit into two reinforced tank containers; (2) A standardized connection method is adopted between the fly ash acid leaching-drying-crushing integrated disposal unit, the fly ash particle and biomass fuel mixing and conveying unit and the smoldering reaction unit. The pipeline sections are connected by quick-release flanges and can be combined, adjusted and disassembled as needed to adapt to different spaces. Rotating snap-on flanges are installed at the interfaces between each unit and the pipeline. When docking, the flange is rotated and locked by electromagnetic induction. The bellows is extended to the set length under the drive of the servo motor, and the pneumatic sealing ring is inflated to achieve double sealing. (3) According to the requirements of heavy metal content and fly ash particle size, the fly ash is washed, acid-leached, oxidized, dried, crushed and screened in order to leach out the heavy metals on the fly ash water-washed residue and obtain fly ash particles with low heavy metal content and meeting the requirements of smoldering particle size. The wastewater after acid leaching can be connected to the wastewater treatment system in the incineration plant through a hose connection; (3) According to the smoldering self-sustaining conditions and the type and calorific value of the biomass used, fly ash particles with a particle size distribution of 4-6 mm and biomass fuel are mixed in proportion to achieve coordinated disposal; (4) Regulating the loading and unloading and ignition process of the smoldering reaction. Fly ash, as a porous medium in the smoldering reaction, not only provides the required activation reaction surface for the smoldering of biomass fuel, but also stores the heat generated by the smoldering and ignites the downstream materials. Adjusting the loading and unloading interval can maintain the stability of the smoldering front, thereby achieving self-sustaining and continuous disposal of the smoldering treatment process; (5) The smoldering peak temperature is maintained at 400-850°C to achieve the desorption or degradation of dioxins in fly ash and activated carbon particles; at the same time, the reducing atmosphere such as CO in the exhaust gas inhibits the regeneration of dioxins; (6) The smoldering reaction exhaust gas is sent into the incinerator of the waste incineration plant through a hose under the action of the induced draft fan and is treated in the incinerator as the primary air of the incinerator.

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