A waste sand regeneration device and regeneration method with low acid value

Abstract

The present invention relates to the field of casting technology, specifically a waste sand regeneration device and a regeneration method with a low acid value. The regeneration device includes a box body, a water inlet pipe, a hopper, a sand-water driving unit, a steam unit, and an ultrasonic unit. The regeneration method involves injecting a fixed amount of water and waste sand, and through the coordinated action of disorderly tumbling, high-temperature steam injection, and ultrasonic oscillation, the inert film and residues on the surface of the waste sand can be effectively removed, realizing the high-quality regeneration of the waste sand.

Description

Technical Field

[0001] The present invention relates to the field of casting technology, and specifically to a waste sand regeneration device and a regeneration method with a low acid consumption value. Background Art

[0002] In the casting industry, molding sand is a key material for mold forming, and its quality and performance directly affect the quality and production efficiency of castings. With the development of casting technology and the improvement of environmental protection requirements, the recycling of molding sand has become the focus of the industry. Among them, the acid consumption value is an important index to measure the alkalinity of molding sand grains. The higher the acid consumption, the greater the alkalinity of the sand grains, that is, the more alkaline substances in the sand grains. Since the curing agent reacts with a part of the alkaline substances on the surface of the sand grains during the sand mixing process after being added, when using molding sand with a relatively high acid consumption value, not only the consumption of resin is relatively high, but also the hardening speed of the mold or core is slowed down. Therefore, for recycled sand, the acid consumption value is usually used to evaluate the quality and recycling effect of recycled sand. The acid consumption value of the original sand is about 4, and the closer the acid consumption value of the recycled sand is to this value, the better the recycling quality.

[0003] The Chinese invention patent with the publication number CN108326231A discloses a waste sand regeneration method for reducing the acid consumption value of recycled sand. Its steps include: 1. Waste sand crushing: crushing the waste sand into fine sand; 2. Roasting: placing the fine sand in a roasting furnace, roasting at 340 - 360 °C for 50 - 70 min first, and then roasting at 640 - 660 °C for 50 - 70 min; 3. Wet stirring regeneration: stirring the fine sand roasted in step 2 in a wet stirring tank containing a dilute acid solution; then the mixture of the fine sand and the dilute acid solution enters a sand - water separator for sand - water separation, and the separated fine sand is dried at 240 - 260 °C for 70 - 90 min; 4. Grinding: grinding the fine sand dried in step 3 with a grinding machine, and the grinding time is 10 - 30 min; 5. Air separation and magnetic separation: removing the sand and dust below 200 mesh from the fine sand ground in step 4 by air separation, and removing the magnetic substances therein by magnetic separation. Although this patent provides a technical solution for reducing the acid consumption value of recycled sand, there are also potential defects: ① The roasting step in this method needs to be carried out in two different temperature ranges, which may lead to higher energy consumption. ② The use of dilute acid solution may have a certain impact on the environment, and wastewater treatment and environmental protection treatment of chemical agents need to be considered. ③ After high - temperature roasting and grinding, the shape and particle size of the sand grains may change, affecting their performance in the casting process. ④ Due to involving multiple steps, the entire regeneration process is relatively long, affecting the regeneration efficiency. Summary of the Invention

[0004] To overcome the problems of low processing efficiency, high cost, large environmental impact, and influence on the shape and particle size of sand grains or one of the above problems existing in the existing sand reclamation technology, a waste sand reclamation device with a low acid consumption value is provided. The technical solution adopted is as follows:

[0005] A waste sand reclamation device with a low acid consumption value, including a box body, a water inlet pipe for injecting or replenishing water into the box body, a hopper for distributing waste sand into the box body. Different from the prior art, it further includes

[0006] A sand-water driving unit, including a sand pump. The inlet of the sand pump is connected to a water-sand outlet provided at the left end of the bottom wall of the box body through a pipeline, and the outlet of the sand pump is connected to a water-sand inlet provided near the top of the right end of the box body through a pipeline;

[0007] A steam unit, including a U-shaped main steam pipe installed at the upper end of the left side wall of the box body. Both ends of the main steam pipe are connected to a waste heat boiler through flanges; The upper ends of a plurality of steam branch pipes are fixedly connected to and communicate with the main steam pipe. The lower ends of the steam branch pipes are closed and close to the bottom wall of the box body, and a plurality of steam nozzles are evenly arranged on the steam branch pipes;

[0008] An ultrasonic unit, including a plurality of ultrasonic vibrators installed on the bottom wall of the box body.

[0009] Further, it further includes a discharging unit. The discharging unit includes a sand pump. A first valve is provided on the pipeline between the outlet of the sand pump and the water-sand inlet. The outlet of the sand pump is also connected to a second valve through a tee. The second valve is connected to the feed inlet of a hydrocyclone through a pipeline, and a sand conveying pipe connected to the sand settling port of the hydrocyclone faces a sand storage yard.

[0010] Further, a constant volume / overflow port is opened at the top of the box body, and the overflow is introduced into the sand storage yard through a pipeline.

[0011] Further, a sewage discharge port is also opened on the bottom wall of the box body. After discharging, broken sand grains, peeled dirt, and inert films deposited at the bottom of the box body are discharged along with a part of the sewage through the sewage discharge port, and the upper clarified clear water is retained.

[0012] Further, it further includes a water recovery unit. The water recovery unit includes a first return water pipe and a second return water pipe provided at the top of the box body. The first return water pipe is connected to the overflow port of the hydrocyclone; The sand storage yard is paved with permeable bricks and provided with a catch basin. The water in the sand pile permeates through the permeable bricks and accumulates in the catch basin, and a water pump pumps the water in the catch basin back to the box body through the second return water pipe.

[0013] Further, it also includes a drying unit, the drying unit includes a rotary drum dryer, and the waste heat of the furnace is introduced into the drum dryer; when the recycled sand piled up in the sand yard is not naturally dried, it is transferred into the rotary drum dryer for rapid drying.

[0014] Further, the bottom wall of the box body includes a slope that gradually rises from left to right, the ultrasonic unit is installed on the slope, and the water-sand outlet is located on the non-slope section.

[0015] Further, the upper end of the box body is covered with a box cover.

[0016] The present invention also provides a method for recycling waste sand with a low acid value, which includes the following steps:

[0017] S1. Inject a certain amount of water and a certain amount of waste sand to be recycled into a container;

[0018] S2. Drive the water and waste sand to tumble disorderly in the container for 0.5 - 2 h, and the sand grains of the waste sand collide with each other, causing the inert film on their surfaces to fall off;

[0019] S3. While performing step S2, spray high-temperature steam into the sand-water suspension, increase the turbulence of the sand-water suspension, raise the temperature of the sand-water suspension, increase the kinetic energy of water molecules, improve the osmosis effect, and the steam bubbles burst to release potential energy, generating an impact force;

[0020] S4. While performing steps S2 and S3, make the water and waste sand vibrate at high frequency in the container through an ultrasonic oscillator, increase the turbulence of the sand-water suspension, increase the kinetic energy of the sand grains of the waste sand, generate cavities, and shatter the inert film on the surface of the sand grains;

[0021] S5. Separate the sand from the water to obtain recycled sand.

[0022] Further, the water separated from the sand and water in step S5 is recycled to step S1.

[0023] Compared with the prior art, the low-consumption acid-value waste sand recycling device and method of the present invention have the following beneficial technical effects:

[0024] 1. Improve the cleaning efficiency:

[0025] Through the circulating action of the sand-water driving unit, the high-frequency vibration of the ultrasonic unit, and the thermal effect of the steam unit, the three cooperate to enhance the cleaning effect on the surface of the waste sand, effectively removing the residues and inert film on the sand grains.

[0026] 2. Reduce energy consumption:

[0027] Avoid the high-energy-consuming roasting step in the traditional method, and use the steam provided by the waste heat boiler and ultrasonic cleaning to reduce energy consumption.

[0028] 3. Reduction of chemical pollution:

[0029] The use of dilute acid solution is abandoned, reducing the risk of chemical pollution to the environment and simultaneously alleviating the burden of wastewater treatment.

[0030] 4. Protection of sand grain integrity:

[0031] Changes in the shape and particle size of sand grains caused by high-temperature roasting are avoided, maintaining the physical properties of sand grains, which is beneficial to improving

[0032] 5. Shortening of the regeneration cycle:

[0033] The integrated device design and synergistic cleaning mechanism shorten the regeneration treatment time of waste sand and improve production efficiency.

[0034] 6. Ease of operation:

[0035] The design of the device simplifies the operation process, is easy to realize automatic control, and reduces the need for manual operation and monitoring.

[0036] 7. Reduction of equipment cost and maintenance cost:

[0037] Compared with traditional regeneration equipment with multiple steps, the device structure of the present invention is more compact, which may reduce the equipment cost and maintenance cost.

[0038] 8. Enhancement of system stability and reliability:

[0039] The integrated unit design reduces the interference of external factors on the cleaning process and improves the stability and reliability of the whole system.

[0040] 9. Enhancement of environmental friendliness:

[0041] The use of chemical agents is abandoned, reducing wastewater discharge, which is in line with the current environmental protection and sustainable development trends.

[0042] 10. Improvement of economic benefits:

[0043] By improving the quality of recycled sand and reducing production costs, the economic benefits of foundries are improved.

[0044] 11. Promotion of resource recycling:

[0045] Effective waste sand regeneration technology helps to improve the resource recycling rate and reduce the demand for new sand resources.

[0046] In summary, through an innovative synergistic cleaning mechanism, the present invention provides an efficient, energy-saving and environmentally friendly waste sand regeneration solution, which helps to promote the transformation of the casting industry towards green manufacturing. Description of the Drawings

[0047] Figure 1 It is a schematic structural diagram of the waste sand regeneration device of the present invention.

[0048] Figure 2 is Figure 1 a sectional view of.

[0049] Reference numerals in the figure: box body - 100, water inlet pipe - 101, hopper - 102, water - sand outlet - 103, water - sand inlet - 104, constant volume / overflow port - 105; ultrasonic unit - 200, ultrasonic vibrator - 201; steam unit - 300, main steam pipe - 301, steam branch pipe - 302; sand - water driving unit - 400, sand pump - 401; discharging unit - 500, first valve - 501, tee - 503, second valve - 502, hydrocyclone - 504, sand conveying pipe - 505, sand storage yard - 506; water recovery unit - 600, sewage outlet, water recovery unit - 600, first water return pipe - 601, second water return pipe - 602, water collection pool - 603, water pump - 604. Detailed implementation manners

[0050] The present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0051] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0052] As Figure 1-2A waste sand regeneration device with a low acid value is shown, including a box body 100, a water inlet pipe 101 for injecting or replenishing water into the box body 100, a hopper 102 for distributing waste sand into the box body 100, and further including a sand-water driving unit 400, a steam unit 300 and an ultrasonic unit 200; the sand-water driving unit 400 includes a sand pump 401, the inlet of the sand pump 401 is connected to a water-sand outlet 103 arranged at the left end of the bottom wall of the box body 100 through a pipeline, and the outlet of the sand pump 401 is connected to a water-sand inlet 104 arranged near the top of the right end of the box body 100 through a pipeline; the steam unit 300 includes a U-shaped main steam pipe 301 installed at the upper end of the left side wall of the box body 100, both ends of the main steam pipe 301 are connected to a waste heat boiler through flanges; the upper ends of a plurality of steam branch pipes 302 are fixedly connected to and communicate with the main steam pipe 301, the lower ends of the steam branch pipes 302 are closed and close to the bottom wall of the box body 100, and a plurality of steam nozzles are evenly arranged on the steam branch pipes 302; the ultrasonic unit 200 includes a plurality of ultrasonic vibrators 201 installed on the bottom wall of the box body 100. The sand pump 401 is a pump for transporting slurries or muds containing solid particles, and is commonly used in industries such as mining, construction, metallurgy, petrochemical industry, river dredging, sugar making, textile and papermaking. The sand pump is designed to handle liquids containing a high concentration of solid particles, is suitable for transporting media containing solid particles, and can work reliably even under harsh working conditions.

[0053] The synergistic action mechanism of the sand-water driving unit, the steam unit and the ultrasonic unit plays a key role in the waste sand regeneration process. The following is a detailed description of their respective functions and synergistic mechanisms:

[0054] Functions and mechanisms of the sand-water driving unit 400:

[0055] The sand-water driving unit realizes the circulating flow of water and waste sand in the box body 100 through the sand pump 401. The inlet of the sand pump 401 is connected to the water-sand outlet 103, and the outlet is connected to the water-sand inlet 104, forming a closed circulation loop. The circulating water flow drives the waste sand particles to form disorderly tumbling in the box body, increasing the collision between sand grains and promoting the detachment of impurities and inert films attached to the surface of sand grains.

[0056] Functions and mechanisms of the steam unit 300:

[0057] The steam unit introduces high-temperature steam into the box through the steam main pipe 301 and makes direct contact with the water-sand mixture. Multiple steam nozzles provided on the steam branch pipe 302 spray the steam evenly, increasing the turbulence of the mixture and raising the temperature of the mixture. The injection of high-temperature steam helps to increase the kinetic energy of water molecules, accelerate the osmosis effect, and make the adhesives in the waste sand easier to peel off. The steam bubbles rise and burst in the box, releasing potential energy and generating an impact force on the surface of the waste sand particles, further promoting the removal of impurities. The steam branch pipe 302 not only serves as a carrier for steam but is also a turbulator. The design and layout of the steam branch pipe 302 can optimize the steam injection method to generate stronger turbulence in the box. This turbulence helps to break up the aggregation of waste sand particles and improve the contact efficiency between them and the vibration generated by the steam and the ultrasonic oscillator 201.

[0058] Function and mechanism of the ultrasonic unit 200:

[0059] The ultrasonic unit generates high-frequency vibrations through the ultrasonic oscillator 201 installed on the bottom wall of the box. The ultrasonic waves propagate in the water medium, driving the water and waste sand to also generate high-frequency vibrations in the container, increasing the turbulence of the sand-water suspension and the kinetic energy of the waste sand particles; at the same time, pressure waves are generated to form a cavitation effect in the water, generating tiny bubbles. These bubbles grow rapidly and suddenly collapse on the surface of the waste sand particles, generating strong microjets and impact forces, shattering the dirt and inert films on the surface of the sand particles; the mechanical action of the ultrasonic waves increases the kinetic energy of the sand particles and improves the collision probability and efficiency.

[0060] Mechanism of the synergistic effect of the three:

[0061] When the sand-water drive unit, the steam unit, and the ultrasonic unit work simultaneously, their effects are superimposed and enhanced. The flow and tumbling provided by the sand-water drive unit provide better contact conditions for the steam and ultrasonic waves. The thermal effect of the steam and the mechanical vibration of the ultrasonic waves act together on the waste sand particles, improving the cleaning efficiency and thoroughness. The thermal energy of the high-temperature steam is combined with the cavitation effect of the ultrasonic waves, accelerating the peeling of the adhesives in the waste sand and reducing the acid consumption value. This synergistic effect not only improves the cleaning efficiency but also reduces the use of chemical cleaning agents, realizing an environmentally friendly and energy-saving waste sand regeneration process. Through this comprehensive physical cleaning method, the waste sand regeneration device can effectively remove impurities in the waste sand, restore its performance, and provide an efficient and environmentally friendly waste sand regeneration solution for the casting industry.

[0062] In another preferred embodiment, it further includes a discharging unit 500. The discharging unit 500 includes a sand pump 401. A first valve 501 is provided on the pipeline between the outlet of the sand pump 401 and the water-sand inlet 104. The outlet of the sand pump 401 is also connected to a second valve 502 through a tee 503. The second valve 502 is connected to the feed inlet of a hydrocyclone 504 through a pipeline. A sand conveying pipe 505 connected to the sand settling port of the hydrocyclone 504 faces a sand storage yard 506. The sand pump 401 has a dual function. In the sand-water driving unit 400, it has the function of driving the sand water circulation and tumbling. At this time, it plays its conveying role and pumps out the mixture of treated waste sand and water from the box body 100. The hydrocyclone 504 separates the waste sand and water by centrifugal force. The heavier and larger sand grains, i.e., the recycled sand, are discharged through the sand settling port, while the lighter broken sand grains, peeled dirt, inert film and water return to the box body 100 through the overflow port. The hydrocyclone 504 efficiently separates the waste sand and water by centrifugal force, ensuring the effective separation of the heavier and larger sand grains, i.e., the recycled sand, from the lighter impurities and water. The recycled sand is directly conveyed to the sand storage yard 506 through the sand conveying pipe 505, which provides convenience for the recovery and reuse of the recycled sand and reduces resource waste. The lighter broken sand grains, peeled dirt and inert film in the overflow port return to the box body 100 with water, avoiding the direct discharge of these impurities into the environment and reducing pollution. The water in the overflow port flows back to the box body 100, realizing the recycling of water resources, improving the water utilization efficiency and saving costs. The setting of the first valve 501 and the second valve 502 improves the controllability of the system, enabling the entire discharging process to be precisely adjusted as needed. The dual function of the sand pump 401 enables the system to adjust its function according to different treatment stages, improving the adaptability and flexibility of the system. By optimizing the design of the discharging unit, the need for additional conveying equipment is reduced, thereby reducing the energy consumption of the entire system. The integrated discharging unit reduces the complexity of multi-equipment operation, simplifies the operation process, and improves the simplicity and safety of operation. By adding the discharging unit in this preferred embodiment, not only the efficiency and quality of waste sand regeneration are improved, but also the efficient recovery of resources and environmental protection are achieved, having good economic and environmental benefits.

[0063] In another preferred embodiment, a constant volume / overflow port 105 is provided at the top of the box body 100. The constant volume / overflow port conducts the overflow water into the sand storage yard 506 through a pipeline. The constant volume / overflow port 105 is used to control the liquid level in the box body and conduct the excess water into the sand storage yard 506 through the pipeline. In this way, each regeneration can have the same volume of water, which is also beneficial for injecting a set volume of waste sand. For example, water: waste sand = 4:1. The constant volume / overflow port 105 helps to standardize the regeneration process, improve the consistency of operation and the predictability of the regeneration effect. Conducting the excess water into the sand storage yard 506 through the pipeline can prevent the water from being directly discharged into the environment, reducing the impact on the environment. Moreover, the sand in the water can be recovered. This design helps to improve the automation level of the entire waste sand regeneration device, reduce manual intervention, and improve the convenience and safety of operation.

[0064] In another preferred embodiment, a sewage discharge port is also provided on the bottom wall of the box body 100. After the discharging is completed, the broken sand grains, peeled dirt and inert film sludge deposited at the bottom of the box body are discharged along with a part of the sewage through the sewage discharge port, and then are subjected to harmless treatment through other means, so as to effectively separate the waste sand and impurities. The clarified water in the upper layer is retained, providing clean water quality for the next regeneration process, improving the reuse rate of water, and reducing resource consumption.

[0065] In another preferred embodiment, a water recovery unit 600 is further included. The water recovery unit 600 includes a first return water pipe 601 and a second return water pipe 602 provided at the top of the box body 100. The first return water pipe 601 is connected to the overflow port of the hydrocyclone 504; the sand storage yard 506 is paved with permeable bricks and provided with a sump 603. The water in the sand pile permeates through the permeable bricks and accumulates in the sump 603. The water pump 604 pumps the water in the sump 603 back into the box body 100 through the second return water pipe 602. Through the water recovery unit 600, the system can recover and reuse water resources, reducing the demand for water resources; the setting of the water recovery unit 600 makes the entire waste sand regeneration system more closed, improves the self-sufficiency rate, reduces the discharge of waste water, reduces the dependence on external water resources, saves the water resource cost, is beneficial to environmental protection, and helps to improve the economic benefits of the entire waste sand regeneration system.

[0066] In another preferred embodiment, it further includes a drying unit, and the drying unit includes a rotary drum dryer. The waste heat of the furnace is introduced into the drum dryer. When the recycled sand piled in the sand yard 506 is not naturally dried, it is transferred into the rotary drum dryer for rapid drying. The rotary drum dryer can rapidly dry the recycled sand in a relatively short time, improving the efficiency of the drying process; using the waste heat of the furnace as the heat source of the dryer realizes the effective reuse of industrial waste heat and reduces energy waste. Even under humid or rainy climate conditions, the drying unit can ensure the drying of the recycled sand, guaranteeing the stability of production.

[0067] In another preferred embodiment, the bottom wall of the box body 100 includes a slope that gradually rises from left to right. The ultrasonic unit 200 is installed on the slope, and the water-sand outlet 103 is located on a non-slope section. The slope design helps to guide the water flow and waste sand to move along the slope, enabling the ultrasonic waves generated by the ultrasonic unit 200 to act more uniformly on the waste sand and enhancing the cleaning effect. The slope structure can cause the waste sand to roll or slide under the action of ultrasonic vibration, helping to break up the aggregation of sand grains and improving the cleaning efficiency. The presence of the slope changes the dynamic characteristics of the water flow, possibly promoting more effective turbulent flow or laminar flow, which helps to improve the mixing and separation of waste sand and water. The slope provides a natural flow path for the waste sand, facilitating the smooth flow of the waste sand after cleaning to the water-sand outlet 103 and reducing the risk of blockage. The ultrasonic unit 200 is installed on the slope, possibly closer to the main area where the waste sand flows, enabling the ultrasonic waves to act more directly on the waste sand and improving the regeneration efficiency.

[0068] In another preferred embodiment, a box cover is provided on the upper end of the box body 100. The box cover provides physical isolation, preventing the safety risks and waste caused by the splashing of the mixture of water and waste sand to the outside of the box body during the operation of the equipment, reducing heat loss, improving energy efficiency, reducing the noise generated during the operation of the equipment, and improving the working environment.

[0069] The waste sand regeneration method of a low-acid-value waste sand regeneration device in this embodiment can be summarized into the following steps:

[0070] S1. Inject a certain amount of water and a certain amount of waste sand to be regenerated into a container;

[0071] S2. Drive the water and waste sand to tumble disorderly in the container for 0.5 - 2 hours, and the sand grains of the waste sand collide with each other, causing the inert film on their surfaces to fall off;

[0072] S3. While performing step S2, spray high-temperature steam into the sand-water suspension, increasing the turbulence of the sand-water suspension, raising the temperature of the sand-water suspension, increasing the kinetic energy of water molecules, improving the osmotic effect, and the bursting of steam bubbles releases potential energy, generating an impact force;

[0073] S4. While performing steps S2 and S3, the water and waste sand are subjected to high-frequency vibration in the container by an ultrasonic oscillator, increasing the turbulence of the sand-water suspension and the kinetic energy of the waste sand grains. At the same time, pressure waves are generated to form a cavitation effect in the water, producing tiny bubbles. These bubbles grow rapidly on the surface of the waste sand particles and suddenly collapse, generating strong microjets and impact forces, which shatter the dirt and inert film on the surface of the sand grains.

[0074] S5. The regenerated sand is obtained by separating the sand from the water. The water separated in step S5 is recycled back to step S1.

[0075] The following table shows the experimental data:

[0076] raw sand reclaimed sand treated by the existing method reclaimed sand treated in this embodiment acid consumption value 4.5 8 6.2

[0077] It can be seen that the regenerated sand processed by this embodiment can effectively reduce the acid consumption value of the sand and gravel, and can reduce the acid consumption value by more than 50%. This waste sand regeneration method realizes the efficient regeneration of waste sand through a series of carefully designed steps, and its excellent effects are mainly reflected in the following aspects:

[0078] Improve the regeneration efficiency: Through the synergistic effect of disorderly tumbling, high-temperature steam injection, and ultrasonic oscillation, the cleaning efficiency of the waste sand surface is greatly improved, and the removal of the inert film and dirt is accelerated.

[0079] Reduce chemical dependence: This method mainly relies on physical means for waste sand cleaning, reducing the dependence on chemical cleaning agents and reducing the risk of chemical pollution in subsequent processing.

[0080] Significant energy-saving effect: The use of high-temperature steam and ultrasonic oscillation improves the cleaning efficiency, shortens the cleaning time, and thus reduces energy consumption.

[0081] Improve water resource utilization rate: In step S5, the water separated is recycled back to step S1, realizing the recycling of water resources, saving water resources and reducing wastewater discharge.

[0082] Improve the quality of regenerated sand: The surface of the cleaned waste sand is cleaner, the acid consumption value is reduced, the quality of the regenerated sand is improved, making it closer to the performance of the original sand and meeting the requirements of industries such as casting.

[0083] Simple operation and high degree of automation: The steps of this method are clear, easy to operate, and can be realized through an automated control system, reducing manual intervention and improving the convenience and safety of operation.

[0084] Environmentally friendly: Reducing the use of chemical cleaning agents and wastewater discharge, reducing the impact on the environment, and conforming to the concepts of green manufacturing and sustainable development.

[0085] Improve production efficiency: The high efficiency of the cleaning process shortens the regeneration cycle of waste sand, improves production efficiency, and speeds up the reuse of waste sand.

[0086] Reduce operating costs: By saving energy, water, and reducing the use of chemical cleaning agents, the operating costs of the entire waste sand regeneration process are reduced.

[0087] Improve system stability: By precisely controlling various parameters during the cleaning process, the stability of the system and the consistency of the regeneration effect are improved.

[0088] Strong adaptability: This method is applicable to the regeneration of waste sand of different types and different pollution degrees, with good adaptability and flexibility.

[0089] In summary, the waste sand regeneration method of this embodiment achieves an efficient, energy-saving, and environmentally friendly waste sand regeneration effect through physical means, improves the quality of the regenerated sand, reduces production costs, and has good industrial application prospects and economic value.

[0090] The above are only preferred embodiments of the present invention and do not limit the present invention in any form; any person skilled in the art can make many possible changes or modifications to the technical solution of the present invention by using the disclosed methods and technical contents without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment with equivalent changes. Therefore, any simple modification, equivalent replacement, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the protection of the technical solution of the present invention.

Claims

1. A waste sand regeneration device with low acid consumption value, comprising a box (100), a water inlet pipe (101) for injecting or replenishing water into the box (100), and a hopper (102) for distributing waste sand into the box (100), characterized in that: Also includes A sand-water driving unit (400) comprises a sand pump (401), wherein the inlet of the sand pump (401) is connected to a water-sand outlet (103) arranged at the left end of the bottom wall of the box body (100) via a pipeline, and the outlet of the sand pump (401) is connected to a water-sand inlet (104) arranged near the top of the right end of the box body (100) via a pipeline; The steam unit (300) comprises a U-shaped steam main pipe (301) installed at the upper end of the left side wall of the box body (100), and the two ends of the steam main pipe (301) are connected to the waste heat boiler through flanges; the upper ends of a plurality of steam branch pipes (302) are fixedly connected to the steam main pipe (301) and communicate with the steam main pipe (301), the lower ends of the steam branch pipes (302) are closed and close to the bottom wall of the box body (100), and a plurality of steam nozzles are evenly arranged on the steam branch pipes (302); The ultrasonic unit (200) comprises a plurality of ultrasonic vibrators (201) mounted on the bottom wall of the box (100).

2. A waste sand regeneration device with low acid consumption value according to claim 1, characterized in that: The device also comprises a discharge unit (500), the discharge unit (500) comprising a sand pump (401), a first valve (501) being arranged on a pipeline between the outlet of the sand pump (401) and the water-sand inlet (104), the outlet of the sand pump (401) being connected to a second valve (502) via a tee (503), the second valve (502) being connected to a feed port of a hydrocyclone (504) via a pipeline, and a sand conveying pipe (505) connected to a sand settling port of the hydrocyclone (504) being directed toward a sand storage area (506).

3. A waste sand regeneration device with low acid consumption value according to claim 2, characterized in that: A set volume / overflow port (105) is opened on the top of the box body (100), and the set volume / overflow port guides the overflow into the sand storage area (506) through a pipeline.

4. A waste sand regeneration device with low acid consumption value according to claim 2, characterized in that: The bottom wall of the box (100) is also provided with a sewage outlet, through which the crushed sand particles, flaked dirt and inert membrane deposited on the bottom of the box are discharged along with a portion of sewage after the discharge is completed, while the clarified water on the upper layer is retained.

5. A waste sand regeneration device with low acid consumption value according to claim 2, characterized in that: It also includes a water recovery unit (600), the water recovery unit (600) including a first water return pipe (601) and a second water return pipe (602) arranged on the top of the box (100), the first water return pipe (601) being connected to the overflow port of the hydrocyclone (504); the sand pile (506) is paved with permeable bricks and a water collection tank (603) is provided, the water in the sand pile passes through the permeable bricks and is collected in the water collection tank (603), and the water pump (604) pumps the water in the water collection tank (603) back to the box (100) through the second water return pipe (602).

6. A waste sand regeneration device with low acid consumption value according to claim 2, characterized in that: It also includes a drying unit, which includes a rotary drum dryer, into which waste heat from a melting furnace is introduced; when the regenerated sand piled in the sand storage area (506) is not naturally dried, it is transferred to the rotary drum dryer for rapid drying.

7. The waste sand regeneration device with low acid consumption value according to claim 1 is characterized in that: The bottom wall of the box (100) comprises a slope that gradually rises from left to right, the ultrasonic unit (200) is installed on the slope, and the water-sand outlet (103) is located in a non-slope section.

8. The waste sand regeneration device with low acid consumption value according to claim 1 is characterized in that: The upper end of the box body (100) is covered with a box cover.

9. The waste sand regeneration method of the waste sand regeneration device according to any one of claims 1 to 8, characterized in that: The following steps are included: S1. Inject a certain amount of water and a certain amount of waste sand to be regenerated into a container; S2. Drive the water and waste sand to tumble disorderly in the container for 0.5-2h, and the sand particles of the waste sand collide with each other, causing the inert film on its surface to fall off; S3. At the same time as step S2, high-temperature steam is sprayed into the sand-water suspension to increase turbulence in the sand-water suspension, increase the temperature of the sand-water suspension, increase the kinetic energy of water molecules, increase osmosis, and release potential energy when steam bubbles burst, generating impact force; S4. At the same time as steps S2 and S3, the water and waste sand are vibrated at high frequency in the container by an ultrasonic oscillator to increase the turbulence of the sand-water suspension and the kinetic energy of the waste sand particles; at the same time, pressure waves are generated to form a cavitation effect in the water, generating tiny bubbles, which grow rapidly on the surface of the waste sand particles and suddenly close, generating strong microjets and impact forces, breaking the dirt and inert film on the surface of the sand particles; S5. Separate sand and water to obtain regenerated sand.

10. The waste sand regeneration method according to claim 9, characterized in that: The water obtained by sand-water separation in step S5 flows back to step S1.

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