Wet sand washing process capable of repeatedly utilizing water resources

Abstract

The invention discloses a wet sand washing process capable of repeatedly utilizing water resources, and relates to the technical field of wet sand making, which comprises the following steps: sand flow cleaning: feeding sand flow screened during wet sand making into a sand washer at a constant speed for vibration sand washing; separation treatment is conducted, specifically, products obtained after sand washing are divided into coarse sand, fine sand and slurry; dehydration treatment: carrying out dehydration treatment on the coarse sand, the fine sand and the slurry, and recovering clear water; tail mud recovery: carrying out tail mud treatment on the dehydrated mud products and the dehydrated fine sand products, and recovering the treated tail mud; according to the technical key points, the sand washing step in the wet sand making process is improved, the recycling of water resources and the recycling treatment of tail mud in the sand washing process can be realized, the resource waste and the environmental pollution are reduced, the dual goals of economic benefits and social benefits are achieved, the overall use effect is good, and the method has a good use prospect.

Description

Technical Field

[0001] The invention relates to the technical field of wet sand making, in particular to a wet sand washing process capable of reusing water resources. Background Art

[0002] In recent years, due to the implementation of mining restrictions and bans on rivers in many regions, the supply of natural river sand resources has become increasingly tight, especially high-quality natural river sand has become more scarce, and the price of river sand has also been rising.

[0003] The use of machine-made sand to prepare concrete can save the high cost of river sand resource mining and long-distance transportation. At the same time, the use of machine-made sand can avoid the impact of river sand supply being banned, restricted or seasonal, thus ensuring the construction period.

[0004] Sand is a major building material and is used in huge quantities in the construction market. Problems with project quality, damage to farmland and water resources caused by excessive exploitation of river sand are becoming increasingly serious. The use of machine-made sand to prepare high-performance concrete is of great significance to protecting the ecological environment.

[0005] Wet sand making refers to the use of water washing during the material screening and crushing process in the sand making production line, and the use of stone washing machines and sand washing machines to wash coarse and fine aggregates.

[0006] The existing patent number is CN112756101A, and the patent name is a wet preparation method and production line for high-purity quartz sand. The invention patent records that the preparation method and production line include coarse crushing-screening treatment, fine crushing-screening treatment, magnetic separation treatment, scrubbing treatment, flotation treatment, gravity separation, and dehydration treatment. Through the above links, an automated continuous production line can be connected in series, realizing the continuous and uninterrupted high-efficiency production of quartz sand. At the same time, the present application is carried out in the mortar state in each link of fine crushing-screening treatment, magnetic separation treatment, scrubbing treatment, flotation treatment, and gravity separation, which belongs to wet sand making, thus reducing the energy consumption of sand making and reducing environmental pollution. In addition, the present application controls the mortar concentration in each link of wet sand making to ensure the treatment effect of each link, and through multi-stage magnetic separation, multi-stage flotation and gravity separation, the impurity content of quartz sand can be less than 50 ppm, and further the impurity content can be less than 30 ppm.

[0007] However, the above method has certain drawbacks when used, just like the prior art. It is mainly used to process the crushing link and the subsequent screening link to reduce impurities, but it has the basic defect of wet sand making when used, that is, a large amount of wastewater and waste mud will be generated in the wet sand making process, which requires additional waste of resources to deal with. Therefore, the overall cost is high, and the resource utilization rate is relatively low, which does not meet people's use requirements. For this reason, we have developed a wet sand washing process that can reuse water resources. Summary of the invention

[0008] 1. Technical issues to be solved

[0009] In view of the shortcomings of the prior art, the present invention provides a wet sand washing process that can reuse water resources. The process improves the sand washing step in the wet sand making process, can realize the reuse of water resources in the sand washing process and the recovery and treatment of tailings, reduce resource waste and environmental pollution, achieve the dual goals of economic and social benefits, and has good overall use effect and good use prospects.

[0010] (II) Technical solution

[0011] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0012] A wet sand washing process capable of reusing water resources comprises the following steps:

[0013] Sand flow cleaning: The sand flow screened during wet sand making is sent to the sand washing machine at a uniform speed for vibration sand washing;

[0014] Separation treatment: the sand washing products are divided into coarse sand, fine sand and mud;

[0015] Dehydration: Dehydration of coarse sand, fine sand and mud, and recovery of clean water;

[0016] Tailings mud recovery: The dehydrated mud products and fine sand products are treated with tailings mud, and the treated tailings mud is recovered.

[0017] Preferably, when classifying the products after sand washing during the separation process, the particle size of sand and gravel is classified, the particle size range of coarse sand is 0.5-2 mm, the particle size range of fine sand is 0.25-0.5 mm, and the particle size range of mud is 0-0.25 mm.

[0018] Preferably, the steps of dehydrating the coarse sand in the dehydration process are as follows:

[0019] The coarse sand in the coarse sand category is screened twice according to the particle size;

[0020] The screened sand and gravel are evenly piled and dehydrated;

[0021] The dehydrated sewage is discharged into the flocculation sedimentation tank for single-stage coagulation and sedimentation;

[0022] The upper layer of clear water in the single-stage coagulation and sedimentation is led to the clear water tank.

[0023] Preferably, the fine sand includes stone powder and soil, and the steps of dehydrating the fine sand during the dehydration process are as follows:

[0024] Use fine sand recovery machine to pre-treat fine sand;

[0025] Discharging the pretreated sewage into a flocculation sedimentation tank for single-stage coagulation sedimentation;

[0026] The upper layer of clear water in the single-stage coagulation and sedimentation is led to the clear water tank.

[0027] Preferably, the pretreated fine sand is evenly stacked and dehydrated, a buffer net is installed inside the flocculation sedimentation tank, the mesh of the buffer net is in the shape of an inverted frustum, a drug dissolving device is installed on the flocculation sedimentation tank, and the clean water tank is connected to the drug dissolving device and the sand washing machine to transport clean water to the drug dissolving device and the sand washing machine.

[0028] The present invention provides a wet sand washing process capable of reusing water resources. A buffer net is used to assist in the sewage sedimentation process so that the settled sand will not be discharged into the next sewage treatment system through a drain port, thereby reducing the sand content and improving the sewage treatment efficiency.

[0029] Preferably, the slurry includes slurry and stone powder. During the dehydration process, a concentrator is used to concentrate and dehydrate the slurry. The concentrator is connected to a clean water tank, and the overflow clean water of the concentrator is led to the clean water tank.

[0030] Preferably, the wastewater generated during the separation process is sent to a flocculation sedimentation tank for flocculation sedimentation.

[0031] Preferably, when treating the tailings of the dehydrated mud products and fine sand products, a plate and frame filter press is used for mechanical dehydration, and the tailings are pressed into a mud cake and stored in a mud cake chamber.

[0032] Preferably, the plate and frame filter press is connected to a clean water tank, and the clean water filtered during tailings treatment flows into the clean water tank.

[0033] The present invention provides a wet sand washing process capable of reusing water resources, which can realize the recycling and treatment of sewage in the whole sand washing process. Part of the recycled clean water can be used for the preparation of reagents, and part of it is stored for cleaning equipment. The sewage after cleaning will flow to the sand washing sewage transfer tank for the recycling of resources. In the whole process, the recycling of resources is fully utilized, the consumption of resources is reduced, and the tailings are converted into valuable resources, the recycling of waste is realized, the purification and reuse of wastewater and tailings are realized, and environmental pollution is reduced. The use effect is good and the use prospect is good.

[0034] (III) Beneficial effects

[0035] The present invention provides a wet sand washing process that can reuse water resources and has the following beneficial effects:

[0036] 1. The present invention provides a wet sand washing process that can reuse water resources. It improves the sand washing step in the wet sand making process, can realize the reuse of water resources in the sand washing process and the recovery and treatment of tailings, reduce resource waste and environmental pollution, achieve the dual goals of economic and social benefits, and has a good overall use effect and a good prospect for use.

[0037] 2. The present invention provides a wet sand washing process that can reuse water resources. A buffer net is used to assist in the sewage sedimentation process so that the settled sand will no longer be discharged into the next sewage treatment system through the drain port, thereby reducing the sand content and improving the sewage treatment efficiency.

[0038] 3. The present invention provides a wet sand washing process that can reuse water resources. It can realize the recycling and treatment of sewage in the whole sand washing process. Part of the recycled clean water can be used for the preparation of reagents, and part is stored for cleaning equipment. The sewage after cleaning will flow to the sand washing sewage transfer tank for the reuse of resources. In the whole process, the reuse of resources is fully utilized, the consumption of resources is reduced, and the tailings are converted into valuable resources, the reuse of waste is realized, the purification and reuse of wastewater and tailings are realized, and environmental pollution is reduced. The use effect is good and it has a good prospect for use. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 The present invention is a flow chart of a wet sand washing process capable of reusing water resources.

[0040] Figure 2 The present invention is a structural block diagram of a wet sand washing process that can reuse water resources. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] Reasons for research

[0043] The existing wet sand making process mainly targets the crushing link and the subsequent screening link to reduce impurities. However, there is a basic defect of wet sand making when it is used, that is, a large amount of wastewater and waste mud will be generated in the process of wet sand making, which requires additional waste of resources to deal with. Therefore, the overall cost is high, and the utilization rate of resources is relatively low, which does not meet people's usage requirements.

[0044] Study plan

[0045] A wet sand washing process capable of reusing water resources comprises the following steps:

[0046] Sand flow cleaning: The sand flow screened during wet sand making is sent to the sand washing machine at a uniform speed for vibration sand washing;

[0047] Separation treatment: the sand washing products are divided into coarse sand, fine sand and mud;

[0048] The present invention combines material properties, natural conditions and market demands to study processing techniques suitable for granite raw materials, such as a composite process of "adjustable soil removal process - multi-stage crushing and screening - full product shaping and re-screening - wet sand washing".

[0049] When classifying the products after sand washing, the particle size of sand and gravel is classified. The particle size range of coarse sand is 0.5-2 mm, the particle size range of fine sand is 0.25-0.5 mm, and the particle size range of mud is 0-0.25 mm;

[0050] The wastewater generated during the separation process is sent to a flocculation sedimentation tank for flocculation and sedimentation;

[0051] Dehydration: Dehydration of coarse sand, fine sand and mud, and recovery of clean water;

[0052] The steps for dehydrating coarse sand are as follows:

[0053] The coarse sand in the coarse sand category is screened twice according to the particle size;

[0054] The screened sand and gravel are evenly piled and dehydrated;

[0055] The dehydrated sewage is discharged into the flocculation sedimentation tank for single-stage coagulation and sedimentation;

[0056] The upper layer of clear water in the single-stage coagulation and sedimentation is led to the clear water tank.

[0057] Fine sand includes stone powder and soil. The steps for dehydrating fine sand are as follows:

[0058] Use fine sand recovery machine to pre-treat fine sand, and evenly pile and dehydrate the pre-treated fine sand;

[0059] Other recovery technologies, such as sedimentation tanks, spiral separators, flotation machines, etc., can also be used to achieve efficient recovery and reuse of fine sand.

[0060] Discharging the pretreated sewage into a flocculation sedimentation tank for single-stage coagulation sedimentation;

[0061] The upper layer of clear water in the single-stage coagulation and sedimentation is led to the clear water tank.

[0062] Other sewage treatment technologies can also be used, such as sedimentation tanks, aeration tanks, biological treatment, etc., to ensure that the sewage meets the discharge standards.

[0063] The mud includes mud and stone powder. During the dehydration process, a concentrator is used to concentrate and dehydrate the mud. The concentrator is connected to a clean water tank, and the overflow clean water of the concentrator leads to the clean water tank.

[0064] A buffer net is installed inside the flocculation sedimentation tank. The mesh of the buffer net is in the shape of an inverted truncated cone. A drug dissolving device is installed on the flocculation sedimentation tank. The clean water tank is connected with the drug dissolving device and the sand washing machine to transport clean water to the drug dissolving device and the sand washing machine.

[0065] In the process of sand washing wastewater treatment, the drug solution is reasonably proportioned through the drug dissolving device, and the agent is fully stirred by the fan blade driven by the motor to make the concentration of the agent consistent. Part of the clean water separated in the wastewater treatment process can be used for the configuration of the agent, and part is stored for cleaning the equipment. The cleaned wastewater will flow to the sand washing wastewater transfer pool for the reuse of resources. In the whole process, the reuse of resources is fully utilized and the consumption of resources is reduced.

[0066] The buffer net can also be replaced by other buffer devices so that the settled sand will no longer be discharged into the next sewage treatment system through the drain outlet, reducing the sand content and improving sewage treatment efficiency.

[0067] The present invention provides a wet sand washing process capable of reusing water resources. A buffer net is used to assist in the sewage sedimentation process so that the settled sand will not be discharged into the next sewage treatment system through a drain port, thereby reducing the sand content and improving the sewage treatment efficiency.

[0068] Tailings mud recovery: The dehydrated mud products and fine sand products are treated with tailings mud, and the treated tailings mud is recovered.

[0069] The invention solves the problem of treating tailing mud generated in the wet production process, studies how to convert tailing mud into valuable resources, and realizes the recycling of waste.

[0070] This method focuses on environmental protection issues in the production process and studies a set of green, intelligent, integrated, high-quality sand and gravel aggregate industrialization technologies to achieve green and sustainable development of the production process.

[0071] When treating the tailings of the dehydrated mud and fine sand products, a plate and frame filter press is used for mechanical dehydration, and the tailings are pressed into mud cakes and stored in mud cake chambers.

[0072] The present invention provides a wet sand washing process capable of reusing water resources, which can realize the recycling and treatment of sewage in the whole sand washing process. Part of the recycled clean water can be used for the preparation of reagents, and part of it is stored for cleaning equipment. The sewage after cleaning will flow to the sand washing sewage transfer tank for the recycling of resources. In the whole process, the recycling of resources is fully utilized, the consumption of resources is reduced, and the tailings are converted into valuable resources, the recycling of waste is realized, the purification and reuse of wastewater and tailings are realized, and environmental pollution is reduced. The use effect is good and the use prospect is good.

[0073] When the present invention is used, the wet sand washing adopts a planar layout. The present invention provides a wet sand washing process that can reuse water resources. The present invention studies how to improve the efficient utilization of resources through the sand washing process, develops processes and technologies that can effectively recover fine sand, reduce material losses, and improve production efficiency.

[0074] The invention provides an effective method for treating wastewater, realizes the purification and reuse of wastewater, and reduces environmental pollution.

[0075] The wet sand washing process of the present invention that can reuse water resources needs to design a reasonable system layout according to the layout and process flow of the factory when in use, including the location of each processing unit, pipeline connection, equipment installation, etc., to maximize the utilization and conservation of resources. It is also necessary to design a reasonable system operation control strategy, including the selection and arrangement of automatic control systems and monitoring equipment to ensure the stable operation and efficient processing effect of the system. At the same time, it is necessary to establish a complete operation and maintenance management mechanism, including regular inspection and maintenance of equipment, troubleshooting, spare parts reserves, etc., to ensure the reliability and stability of the system.

[0076] In the system design and operation, the present invention pays attention to safety and environmental protection requirements, takes corresponding safety measures, such as fire prevention, explosion prevention, anti-slip, etc., and strengthens the management and monitoring of wastewater, waste gas, noise, etc.

[0077] The present invention evaluates the economic and social benefits of a granite crushed stone wet processing fine sand recovery and sewage treatment system, including evaluation and analysis of investment cost, operation cost, resource conservation degree, environmental protection benefit and other aspects.

[0078] The above scheme aims to achieve the recycling of fine sand and efficient treatment of sewage during the wet processing of granite crushed stone, reduce resource waste and environmental pollution, and achieve the dual goals of economic and social benefits. In the specific implementation process, it is necessary to adjust and optimize according to the actual situation.

[0079] According to the above process, the sand produced in the wet sand making process is washed. After testing, the water resource recovery rate is more than 90%, which can greatly save water resources. The recovered tailings are made into mud cakes, which can enhance the stability of the well wall in the drilling project, prevent the well wall from collapsing, and ensure the safety of the drilling operation. The mud cake can effectively control the water loss of the drilling fluid and avoid the excessive loss of water, thereby maintaining the stability of the physical properties of the drilling fluid, playing a lubricating role, reducing the friction between the drill bit and the well wall, making the drill bit smoother during the drilling process, and reducing the risk of wear and sticking.

[0080] According to the above process, the sand produced in the wet sand making process is washed, and the sand is screened and stacked separately during the sand washing process, which can effectively save subsequent processing steps, meet the product's particle shape, graded particle size, product ratio and quality requirements, and ensure that the final product meets the specification requirements and can meet market demand; and after stacking dehydration and other dehydration technologies, the water content of the sand is below 8%, which is more convenient to use.

[0081] In summary, the research on a wet sand washing process that can reuse water resources in the present invention not only has significant economic benefits, but also brings important social benefits, and has a positive impact on improving the safety, sustainability and social image of mines.

[0082] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A wet sand washing process capable of reusing water resources, characterized in that: The following steps are involved: Sand flow cleaning: The sand flow screened during wet sand making is sent to the sand washing machine at a uniform speed for vibration sand washing; Separation treatment: the sand washing products are divided into coarse sand, fine sand and mud; Dehydration: Dehydration of coarse sand, fine sand and mud, and recovery of clean water; Tailings mud recovery: The dehydrated mud products and fine sand products are treated with tailings mud, and the treated tailings mud is recovered.

2. The wet sand washing process capable of reusing water resources according to claim 1, characterized in that: In the step of separation treatment, the sand and gravel are classified according to their particle sizes when the sand washing products are classified. The particle size range of the coarse sand is 0.5-2 mm, the particle size range of the fine sand is 0.25-0.5 mm, and the particle size range of the mud is 0-0.25 mm.

3. A wet sand washing process capable of reusing water resources according to claim 2, characterized in that: The steps for dehydrating the coarse sand during the dehydration process are as follows: The coarse sand in the coarse sand category is screened twice according to the particle size; The screened sand and gravel are evenly piled and dehydrated; The dehydrated sewage is discharged into the flocculation sedimentation tank for single-stage coagulation and sedimentation; The upper layer of clear water in the single-stage coagulation and sedimentation is led to the clear water tank.

4. A wet sand washing process capable of reusing water resources according to claim 3, characterized in that: Fine sand includes stone powder and soil. The steps for dehydrating fine sand during the dehydration process are as follows: Use fine sand recovery machine to pre-treat fine sand; Discharging the pretreated sewage into a flocculation sedimentation tank for single-stage coagulation sedimentation; The upper layer of clear water in the single-stage coagulation and sedimentation is led to the clear water tank.

5. A wet sand washing process capable of reusing water resources according to claim 4, characterized in that: The pretreated fine sand is evenly stacked and dehydrated, a buffer net is installed inside the flocculation sedimentation tank, the mesh of the buffer net is in the shape of an inverted truncated cone, a drug dissolving device is installed on the flocculation sedimentation tank, and the clean water tank is connected with the drug dissolving device and the sand washing machine to transport clean water to the drug dissolving device and the sand washing machine.

6. A wet sand washing process capable of reusing water resources according to claim 5, characterized in that: The mud includes mud and stone powder. During the dehydration process, a concentrator is used to concentrate and dehydrate the mud. The concentrator is connected to a clean water tank, and the overflow clean water of the concentrator leads to the clean water tank.

7. A wet sand washing process capable of reusing water resources according to claim 6, characterized in that: The wastewater generated during the separation process is sent to a flocculation sedimentation tank for flocculation sedimentation.

8. The wet sand washing process capable of reusing water resources according to claim 7, characterized in that: When treating the tailings of the dehydrated mud and fine sand products, a plate and frame filter press is used for mechanical dehydration, and the tailings are pressed into mud cakes and stored in mud cake chambers.

9. A wet sand washing process capable of reusing water resources according to claim 8, characterized in that: The plate-and-frame filter press is connected to a clean water tank, and clean water from the filter press flows into the clean water tank during tailings treatment.

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