A steel strip grinding and polishing wastewater treatment system

Abstract

The present invention relates to the technical field of sewage treatment, and discloses a steel strip grinding and polishing wastewater treatment system, comprising a coarse grinding sedimentation tank, a coarse grinding water storage tank, and a coarse grinding filter press, wherein the coarse grinding sedimentation tank is connected to the coarse grinding water storage tank, the coarse grinding water storage tank reuses water to the coarse grinding unit, the coarse grinding sedimentation tank is connected to the coarse grinding filter press, and the water after solid-liquid separation flows back to the coarse grinding water storage tank; the system also comprises a flat bed filter, a fine grinding circulation tank, a wastewater storage tank, a fine grinding neutralization tank, a fine grinding sedimentation tank, a fine grinding filter press, a water storage tank, and a medicine mixing water tank, the fine grinding sedimentation tank and the coarse grinding water storage tank are connected to a membrane treatment device via a pipeline, and the membrane treatment device is connected to the water storage tank. After the coarse grinding wastewater and the fine grinding wastewater are treated, the recycled water in the coarse grinding water storage tank can be reused to the coarse grinding unit, and the grinding liquid in the fine grinding circulation tank can be reused to the fine grinding unit, and the fine grinding and coarse grinding wastewaters are subjected to membrane treatment, and the fine grinding wastewater is neutralized and filtered for a second time before being collected in the water storage tank, thereby improving the utilization rate of the water body.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a steel strip grinding and polishing wastewater treatment system. Background Art

[0002] 8K steel refers to cold-rolled stainless steel coils that have undergone grinding and polishing to achieve a smooth, mirror-like finish. The existing grinding and polishing production line includes an uncoiler, pinch rollers, straightener, sander, rough grinding unit, fine grinding unit, cleaning unit, dryer, laminating machine, and winder. The sander and rough grinding units use water, sanding belts, and fiber grinding heads to remove the oxide layer from the steel coil surface. The rough grinding generates wastewater containing impurities such as metal shavings and metal particles, which requires treatment before recycling or disposal. The fine grinding unit uses an acidic grinding fluid and wool grinding heads to polish the steel coil surface. This polishing generates acidic wastewater containing metal particles, which also requires treatment before reuse or disposal. Existing stainless steel polishing wastewater treatment equipment typically includes a wastewater collection tank, a reaction water tank, a concentration water tank, a solid-liquid separation system, and a sludge dewatering unit. The clean water from the solid-liquid separation system is discharged, the concentrated water is returned to the concentration water tank, and the filtrate from the sludge dewatering unit is returned to the concentration water tank. The reaction water tank utilizes high-voltage pulsed electrocoagulation. However, the above wastewater treatment device does not specifically treat the coarse grinding wastewater and the fine grinding wastewater separately, but collects the stainless steel wastewater and then treats it. Although the water quality of the treated water meets the standard, it puts a heavy load on the entire sewage treatment system.

[0003] It can be seen that the existing technology still needs to be improved and enhanced. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a steel strip grinding and polishing wastewater treatment system, aiming to ensure that the wastewater can meet both discharge requirements and be reused in the coarse grinding unit and the fine grinding unit.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A steel strip grinding and polishing wastewater treatment system includes a coarse grinding sedimentation tank, a coarse grinding water storage tank, a coarse grinding lift pump and a coarse grinding filter press. The upper part of the coarse grinding sedimentation tank is connected to the coarse grinding water storage tank, and the coarse grinding water storage tank reuses water to the coarse grinding unit through the coarse grinding lift pump. The lower part of the coarse grinding sedimentation tank is connected to the coarse grinding filter press, and the water after solid-liquid separation in the coarse grinding filter press flows back to the coarse grinding water storage tank; the steel strip grinding and polishing wastewater treatment system also includes a flat bed filter, a fine grinding circulation tank, a centrifugal pump, a wastewater storage barrel, a fine grinding neutralization barrel, a fine grinding sedimentation barrel, a fine grinding filter press, and a water storage barrel connected in sequence. The fine grinding circulation tank is also connected to a preparation medicine barrel. The water body in the upper part of the fine grinding and fine grinding sedimentation barrel and the coarse grinding wastewater in the coarse grinding water storage tank are connected to a membrane treatment device through a pipeline, and the membrane treatment device is connected to the water storage barrel.

[0007] The steel strip grinding and polishing wastewater treatment system further includes a circulating water pool connected to the cleaning wastewater of the cleaning unit through a pipeline, and the outlet end of the circulating water pool is connected to the coarse grinding sedimentation tank.

[0008] The steel strip grinding and polishing wastewater treatment system, wherein the water treated by the membrane treatment device and the water treated by the fine grinding filter press are transported to the low-temperature vacuum evaporator through a pipeline, and the water treated by the low-temperature vacuum evaporator is transported to the water storage tank.

[0009] The steel strip grinding and polishing wastewater treatment system further includes an acid mist tower connected to the water storage barrel, the inlet end of the acid mist tower is connected to the fine grinding unit, and the outlet end of the acid mist tower is connected to the wastewater storage barrel.

[0010] The steel strip grinding and polishing wastewater treatment system, wherein the coarse grinding sedimentation tank is arranged in multiple stages, adjacent coarse grinding sedimentation tanks are connected by pipes, the distance between the water outlet at the top of each stage and the corresponding top of the coarse grinding sedimentation tank gradually increases, and the corresponding pipe extends into the bottom of the adjacent coarse grinding sedimentation tank.

[0011] The steel belt grinding and polishing wastewater treatment system, wherein the coarse grinding filter press, the flat bed filter and the fine grinding filter press each include a frame, a mesh belt arranged on the frame, a bracket arranged upstream of the frame and used to support a roller body around which a filter cloth is wound, a storage portion arranged downstream of the frame and used to recover the filter cloth, and a driving mechanism for driving the mesh belt to drive the filter cloth to move in a downstream direction; the bracket is located upstream of the frame.

[0012] The steel belt grinding and polishing wastewater treatment system is characterized in that a U-shaped groove is provided on the upper part of the bracket, and the two ends of the roller body around which the filter cloth is wound are respectively arranged in the two U-shaped grooves; the roller body of the filter cloth is perpendicular to the moving direction of the mesh belt.

[0013] The steel belt grinding and polishing wastewater treatment system, wherein the frame is provided with a mounting bracket spanning both sides of the frame, and the mounting bracket is provided with a float liquid level sensor, and the float liquid level sensor is electrically connected to the driving mechanism; the float liquid level sensor is located downstream of the bracket, and the float liquid level sensor is used to sense the height of the sediment on the filter cloth; the mounting bracket is provided with a support plate, the support plate is connected to the mounting plate, and the float liquid level sensor is provided on the mounting plate; the mounting plate is provided with a waist-shaped hole extending along its length direction, and the support plate is provided with a locking rod passing through the upper and lower side walls of the support plate, the locking rod passes through the waist-shaped hole, and the end of the locking rod is threadedly connected to a locking nut, and the side wall of the locking nut abuts against the upper end face or lower end face of the support plate.

[0014] The steel strip grinding and polishing wastewater treatment system, wherein the membrane treatment device includes a raw water tank, a sand filter, a carbon filter, a first safety filter, an ultrafiltration device, an ultrafiltration water tank, a second safety filter, a first-level reverse osmosis membrane, a first-level reverse osmosis water tank, and a second-level reverse osmosis membrane connected in sequence; the concentrated water treated by the first-level reverse osmosis membrane flows to the concentrated water collection tank, and the concentrated water collection tank is connected to the low-temperature vacuum evaporator through a pipeline; the water treated by the second-level reverse osmosis membrane flows to the water storage tank.

[0015] The steel strip grinding and polishing wastewater treatment system, wherein the concentrated water collection tank is connected to the three-stage reverse osmosis membrane, the water treated by the three-stage reverse osmosis membrane flows through the pipeline to the first-stage reverse osmosis water tank, and the concentrated water treated by the three-stage reverse osmosis membrane flows back to the concentrated water collection tank.

[0016] Beneficial effects:

[0017] The present invention provides a wastewater treatment system for steel strip grinding and polishing. The wastewater generated in the fine grinding stage is preliminarily precipitated and the precipitate is filtered. Part of the recycled water generated is reused in the coarse grinding water storage tank, and the other part of the recycled water is purified and filtered again, so that the recycled water with less impurities in the coarse grinding water storage tank can be extracted to the coarse grinding unit for recycling, which can improve the utilization rate of the recycled water and reduce the load of the wastewater treatment system.

[0018] The acidic wastewater is first filtered through a flat bed filter for the first time. The filtered water flows into the fine grinding circulation pool and is mixed with the medicine in the medicine mixing barrel to form a grinding liquid, which is reused in the fine grinding unit. The other part of the filtered water containing sediment enters the fine grinding neutralization barrel and the fine grinding sedimentation barrel for neutralization and purification. The water in the upper layer of the fine grinding sedimentation barrel is desalinated by a membrane treatment device, and the water in the lower layer is filtered for the second time by a fine grinding filter press to form recycled water with lower conductivity. The recycled water is pumped into the water storage barrel for standby use.

[0019] The water in the water storage tank can be reused on the grinding head of the fine grinding unit for cleaning the grinding head; it can also be reused in the preparation water tank for preparing grinding liquid; it can also be extracted to the cleaning unit for use in the last cleaning machine; it can also be used to clean the acid mist tower and change the water in the acid mist tower. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a structural schematic diagram of the steel strip grinding and polishing wastewater treatment system provided by the present invention.

[0021] Figure 2 This is a structural diagram of the coarse grinding unit.

[0022] Figure 3 This is a structural diagram of the fine grinding unit.

[0023] Figure 4 Schematic diagram of the structure of the membrane treatment device.

[0024] Figure 5 It is a structural diagram of a flat bed filter.

[0025] Figure 6 It is a structural schematic diagram of the flat bed filter after the filter cloth is pulled out.

[0026] Figure 7 It is a schematic diagram of the local structure of the flat bed filter.

[0027] Figure 8 It is a structural diagram of the tension adjustment mechanism.

[0028] Description of main component symbols:

[0029] C-coarse grinding unit, C10-coarse grinding sedimentation tank, C20-coarse grinding water storage tank, C30-coarse grinding lift pump, C40-coarse grinding filter press;

[0030] J-fine grinding unit, J10-flat bed filter, J11-frame, J111-limiting frame, J12-mesh belt, J13-bracket, J131-U-shaped groove, J14-storage part, J15-driving mechanism, J151-driving motor, J152-reducer, J153-driving shaft, J154-driven shaft, J160-mounting frame, J161-support plate, J162-mounting plate, J1621-waist-shaped hole, J163-locking rod, J164-locking nut, J165-float liquid level sensor, J170-tension adjustment mechanism, J171-tension frame, J172-bearing, J173-screw, J174-adjusting nut, J20-fine grinding circulation pool, J30-medicine mixing barrel, J40-wastewater storage barrel, J50-fine grinding neutralization barrel, J60-fine grinding sedimentation barrel, J70-fine grinding filter press, J80-acid mist tower;

[0031] Q-cleaning unit, Q10-circulating water pool;

[0032] 10-Membrane treatment device, 101-Raw water tank, 102-Sand filter, 103-Carbon filter, 104-First safety filter, 105-Ultrafiltration device, 106-Ultrafiltration water tank, 107-Second safety filter, 108-First level reverse osmosis membrane, 109-First level reverse osmosis water tank, 110-Second level reverse osmosis membrane, 111-Concentrated water collection tank, 112-Third level reverse osmosis membrane;

[0033] 20- low temperature vacuum evaporator, 30- water storage barrel;

[0034] 200-Filter cloth. DETAILED DESCRIPTION

[0035] The present invention provides a system for treating wastewater from steel strip grinding and polishing. To clarify the objectives, technical solutions, and effects of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific examples described herein are intended only to illustrate the present invention and are not intended to limit its scope.

[0036] See also Figure 1-Figure 3 The present invention provides a steel belt grinding and polishing wastewater treatment system, comprising a coarse grinding sedimentation tank C10, a coarse grinding water storage tank C20, a coarse grinding lifting pump C30 and a coarse grinding filter press C40, wherein the upper part of the coarse grinding sedimentation tank C10 is connected to the coarse grinding water storage tank C20, and the coarse grinding water storage tank C20 reuses water to the coarse grinding unit C through the coarse grinding lifting pump C30, and the lower part of the coarse grinding sedimentation tank C10 is connected to the coarse grinding filter press C40, and the water after solid-liquid separation in the coarse grinding filter press C40 is returned to the coarse grinding water storage tank C20; the steel belt The grinding and polishing wastewater treatment system also includes a flat bed filter J10, a fine grinding circulation tank J20, a centrifugal pump (not shown in the figure), a wastewater storage tank J40, a fine grinding neutralization tank J50, a fine grinding sedimentation tank J60, a fine grinding filter press J70, and a water storage tank 30 connected in sequence. The fine grinding circulation tank J20 is also connected to a preparation medicine tank J30. The water body above the fine grinding sedimentation tank J60 and the coarse grinding wastewater in the coarse grinding water storage tank C20 are connected to the membrane treatment device 10 through a pipe, and the membrane treatment device 10 is connected to the water storage tank 30.

[0037] In actual application, there are two sanding machines, the coarse grinding machine group C consists of fourteen coarse grinders, and the fine grinding machine group J consists of sixteen fine grinders. The sanding machine and the coarse grinder use water to grind the oxide layer on the surface of the steel belt, and the coarse grinder uses grinding fluid to polish the steel belt. The polished steel belt enters the cleaning unit Q to clean the residual acidic grinding fluid on the steel belt.

[0038] See also Figure 2 Coarse grinding wastewater: The wastewater containing metal particles generated during the coarse grinding stage is collected and piped into the coarse grinding sedimentation tank C10. After sedimentation, a certain amount of metal particles, sludge, etc. are deposited at the bottom of the coarse grinding sedimentation tank C10. The upper part of the coarse grinding sedimentation tank C10 becomes relatively clear, and the upper water flows through the outlet at the top of the coarse grinding sedimentation tank C10 to the coarse grinding water storage tank C20. In addition, the water-containing sediment in the coarse grinding sedimentation tank C10 is transported through a pipe to the coarse grinding filter press C40. After the water in the sediment is filtered by the coarse grinding filter press C40, solid waste residue and recycled water are formed. The solid waste residue is collected and recycled by an external cleaning company. A portion of the recycled water is lifted to the coarse grinding water storage tank C20, and the coarse grinding lifting pump C30 extracts the recycled water in the water storage tank to the coarse grinding unit C for use by multiple coarse grinding machines; the other portion of the recycled water is transported through a pipeline to the membrane treatment device 10 for removal of suspended matter, desalination, etc., and the water after membrane treatment is transported to the water storage tank 30.

[0039] In the above arrangement, the wastewater generated in the fine grinding stage is first precipitated and the precipitate is filtered. Part of the recycled water is reused in the coarse grinding water storage tank C20, and the other part of the recycled water is purified and filtered again, so that the recycled water with less impurities in the coarse grinding water storage tank C20 can be extracted to the coarse grinding unit C for recycling, which can improve the utilization rate of the recycled water and reduce the load on the wastewater treatment system.

[0040] See also Figure 3Fine grinding wastewater: The acidic wastewater generated in the fine grinding stage is collected and transported through a pipeline to the flat bed filter J10 for the first filtration. After filtration, solid hazardous waste and filtered water are formed. The filtered water flows from the bottom of the flat bed filter J10 to the conical fine grinding circulation tank J20. In addition, chemicals are added to the mixing water barrel J30 (a mixture of polishing powder, defoaming agent, nitric acid, aluminum oxide and recycled water to form an acidic grinding liquid. The mixing water barrel J30 is also equipped with an agitator for dissolving the chemicals). The grinding liquid in the mixing water barrel J30 flows through a pipeline to the fine grinding circulation tank J20. The water in the fine grinding circulation tank J20 is separated by the centrifugal action of the centrifugal pump, and the relatively clean acidic recycled water is transported to the grinding head of the fine grinding unit J. The wastewater (containing impurities such as sludge and metal particles) separated by the centrifugal pump is transported to the wastewater storage barrel J40 through a pipeline. The wastewater in the wastewater storage barrel J40 gradually enters the fine grinding and neutralization barrel J50, and a neutralizing agent composed of caustic soda (sodium hydroxide, acid neutralizer, precipitant), polyacrylamide (PAM, used in combination with other inorganic flocculants, can greatly reduce the use of flocculants. It significantly improves the water quality of the effluent. It increases the floc strength and sedimentation rate), and polyaluminum chloride (PAC, an inorganic polymer coagulant) is added to the fine grinding and neutralization barrel J50 through a pipeline. After the water body is added with the above-mentioned neutralizing agent, it is stirred by the agitator in the fine grinding and neutralization barrel J50, so that the neutralizing agent and the acidic substances in the water body fully react. The water body then flows to the fine grinding sedimentation barrel J60 through a pipeline, and alum floc sediment (containing salt, metal, etc.) is precipitated. In this embodiment, the fine grinding and neutralization barrel J50 and the fine grinding and sedimentation barrel J60 are arranged in parallel, or the fine grinding and neutralization barrel J50 can be hidden and the neutralization agent can be directly added into the fine grinding and sedimentation barrel J60.

[0041] In the above-mentioned setting, the acidic wastewater first passes through the flat bed filter J10 for the first filtration, and the filtered water flows into the fine grinding circulation pool J20, and is mixed with the medicine in the preparation medicine barrel J30 to form a grinding liquid, which is reused to the fine grinding unit J. The other part of the filtered water containing sediment enters the fine grinding neutralization barrel J50 and the fine grinding sedimentation barrel J60 for neutralization and purification. The water in the upper layer of the fine grinding sedimentation barrel J60 is desalinated by the membrane treatment device 10, and the water in the lower layer is filtered for the second time by the fine grinding filter press J70 to form recycled water with lower conductivity. The recycled water is pumped into the water storage barrel 30 for standby use.

[0042] After the treatment of the coarse grinding wastewater and the fine grinding wastewater, the recycled water in the coarse grinding water storage tank C20 can be reused in the coarse grinding unit C, and the grinding liquid in the fine grinding circulation tank J20 can be reused in the fine grinding unit J. The coarse grinding and fine grinding wastewater are also treated by membranes, and the fine grinding wastewater is also neutralized and filtered for the second time. The water is collected in the water storage tank 30. The water in the water storage tank 30 can be reused on the grinding head of the fine grinding unit J for cleaning the grinding head; it can also be reused in the preparation water tank J30 for preparing the grinding liquid.

[0043] See also Figure 1 and Figure 3 In some embodiments, a circulating water tank Q10 is further included, which is connected to the cleaning wastewater of the cleaning unit Q via a pipeline, and the outlet end of the circulating water tank Q10 is connected to the coarse grinding sedimentation tank C10. In this embodiment, two circulating water tanks Q10 are provided to collect the wastewater generated by the cleaning unit Q when cleaning the steel strip, and circulate it for cleaning the steel strip. The recycled water in the water storage tank 30 can also be extracted to the cleaning unit Q for use in the last cleaning machine. In addition, when the water in the circulating water tank Q10 needs to be replaced (that is, when the water in the circulating water tank Q10 contains an extremely high content of metal ions, or when the impurities in the water are visually increased), the water in the circulating water tank Q10 will flow through the pipeline to the coarse grinding sedimentation tank C10, and the pipeline for the cleaning section water circulation is equipped with a basket filter and a security filter to filter impurities such as brush hairs and grinding head fragments in the circulating section water. As the unit operates, the wastewater generated by the cleaning unit Q when cleaning the steel belt contains a certain amount of acidity. Therefore, a coarse grinding neutralization tank and a coarse grinding sedimentation tank can be set on the pipeline between the coarse grinding water storage tank C20 and the membrane treatment to neutralize the acidic substances in the coarse grinding wastewater.

[0044] See also Figure 1 and Figure 3 In certain embodiments, the water treated by the membrane treatment device 10 and the water treated by the fine grinding filter press J70 are transported to the low-temperature vacuum evaporator 20 via a pipeline, and the water treated by the low-temperature vacuum evaporator 20 is transported to the water storage tank 30. The concentrated liquid after membrane treatment and the fine grinding wastewater filtered by the fine grinding filter press J70 enter the low-temperature vacuum evaporator 20 and are heated to boiling point in a vacuum. Water evaporates from the wastewater to form water vapor, which is collected in the water storage tank 30 through a mobile phone. Substances with a higher boiling point than water (such as salt, heavy metals, grease, etc.) remain in the residual liquid. In other words, the water in the wastewater is evaporated by the low-temperature vacuum evaporator 20 to form concentrated liquid hazardous waste, thereby reducing the amount of hazardous waste to be processed, that is, reducing the cost of hazardous waste treatment by the cleaning company.

[0045] See also Figure 1 and Figure 3In some embodiments, an acid mist tower J80 connected to the water storage barrel 30 is further included. The inlet end of the acid mist tower J80 is connected to the fine grinding unit J, and the outlet end of the acid mist tower J80 is connected to the wastewater storage barrel J40. When the fine grinding unit J is in operation, the grinding head and the steel belt are physically rubbed, which generates heat. When the heat comes into contact with the acidic grinding liquid, it evaporates into acidic water mist. Alkaline water is added to the acid mist tower J80 to neutralize the acidic water mist. The neutralized wastewater also enters the wastewater storage barrel J40 through a pipeline and waits for treatment. The recycled water in the water storage barrel 30 has a fourth use, namely, it is used to clean the acid mist tower J80 and to replace the water in the acid mist tower J80.

[0046] See also Figure 1 and Figure 2 In some embodiments, the coarse grinding sedimentation tanks C10 are arranged in multiple stages, with adjacent coarse grinding sedimentation tanks C10 connected by pipes. The water outlet at the top of each coarse grinding sedimentation tank C10 is located at a gradually increasing height from the top of the corresponding coarse grinding sedimentation tank C10, and the corresponding pipes extend into the bottom of the adjacent coarse grinding sedimentation tank C10. This embodiment shows three coarse grinding sedimentation tanks C10 arranged in sequence, with the water outlet at the top of each coarse grinding sedimentation tank C10 gradually decreasing in height from the ground. This allows the height of the water in each coarse grinding sedimentation tank C10 to gradually decrease, achieving overflow. Specifically, the clearer water in the upper layer of the coarse grinding sedimentation tank C10 flows by gravity to the coarse grinding sedimentation tank C10 of the next stage. After three rounds of sedimentation, the water in each coarse grinding sedimentation tank C10 gradually becomes clear until it can be used again in the coarse grinding process of the coarse grinding unit C.

[0047] See also Figure 5 and Figure 6In some embodiments, the coarse grinding filter press C40, the flat bed filter press J10, and the fine grinding filter press J70 each include a frame J11, a mesh belt J12 mounted on the frame J11, a bracket J13 positioned upstream of the frame J11 for supporting a roller around which a filter cloth 200 is wound, a storage portion J14 positioned downstream of the frame J11 for recovering the filter cloth 200, and a drive mechanism J15 for driving the mesh belt J12 to move the filter cloth 200 downstream. The bracket J13 is positioned upstream of the frame J11. During operation, sediment is discharged from the outlet of the pipe and falls onto the filter cloth 200. Water in the sediment is filtered by the filter cloth 200 and collected through the meshes of the mesh belt J12 into the membrane treatment device 10, the fine grinding circulation tank J20 below the frame J11, or the low-temperature vacuum evaporator 20. The sediment trapped on the filter cloth 200 moves downstream under the driving action of the driving mechanism J15 and the mesh belt J12, so that the filter cloth 200 is recovered into the storage part J14, and the clean filter cloth 200 is pulled out from the bracket J13, so that the filter cloth 200 located under the pipeline is new, and solid-liquid separation is achieved through the above arrangement.

[0048] See also Figure 5 and Figure 6 In some embodiments, the upper portion of the bracket J13 is provided with U-shaped grooves J131. The ends of the roller around which the filter cloth 200 is wound are respectively positioned within the two U-shaped grooves J131. The roller of the filter cloth 200 is perpendicular to the direction of movement of the mesh belt J12. The bracket J13 is used to support the roller of the filter cloth 200 at a certain height from the frame J11 to prevent the filter cloth 200 wound around the roller from becoming contaminated. The U-shaped grooves J131 are provided to support the ends of the roller. As the filter cloth 200 is pulled, the roller rotates within the U-shaped grooves J131, and the U-shaped grooves J131 act as a limiter to prevent the roller from falling out of the U-shaped grooves J131.

[0049] See also Figure 5 and Figure 6In some embodiments, the drive mechanism J15 includes a drive motor J151, a reducer J152 connected to the output end of the drive motor J151, a driving shaft J153 connected to the reducer J152, and a driven shaft J154 parallel to the driving shaft J153. The mesh belt J12 is wound between the driving shaft J153 and the driven shaft J154, and the driving shaft J153 and the driven shaft J154 respectively extend through both sides of the frame J11. When the drive motor J151 rotates in the forward direction, the driving shaft J153 rotates, which in turn rotates the mesh belt J12, which in turn rotates the driven shaft J154. The wetted filter cloth 200 has a certain weight, so the filter cloth 200, which has trapped sediment, clings to the mesh belt J12. The rotation of the mesh belt J12 pulls the filter cloth 200 downstream, allowing clean filter cloth 200 to be continuously drawn out.

[0050] See also Figure 7 In some embodiments, the frame J11 is provided with a mounting bracket J160 spanning both sides of the frame J11, and a float liquid level sensor J165 is provided on the mounting bracket J160. The float liquid level sensor J165 is electrically connected to the driving mechanism J15; the float liquid level sensor J165 is located downstream of the bracket J13, and the float liquid level sensor J165 is used to sense the height of the sediment on the filter cloth 200. The float liquid level sensor J165 is located above the sediment. When the height of the sediment on the filter cloth 200 reaches the moving height, it means that the filter cloth 200 at this location is in a saturated state, that is, the filtration efficiency of the filter cloth 200 at this location is relatively low. At this time, the float liquid level sensor J165 transmits a signal to the drive mechanism J15, which drives the drive mechanism J15 to drive the mesh belt J12 and the filter cloth 200 to move downstream, so that the new and clean filter cloth 200 is located below the pipeline, and the water-containing sediment flowing out of the pipeline is quickly filtered, thereby avoiding excessive sediment deposition on the filter cloth 200 and affecting the filtration efficiency.

[0051] See also Figure 7In some embodiments, a support plate J161 is provided on the mounting frame J160, and the support plate J161 is connected to the mounting plate J162, and the float liquid level sensor J165 is provided on the mounting plate J162; the mounting plate J162 is provided with a waist-shaped hole J1621 extending along its length direction, and the support plate J161 is provided with a locking rod J163 passing through the upper and lower side walls of the support plate J161, the locking rod J163 passes through the waist-shaped hole J1621, and the end of the locking rod J163 is threadedly connected to a locking nut J164, and the side wall of the locking nut J164 abuts against the upper end surface or the lower end surface of the support plate J161. By setting a waist-shaped hole J1621 extending left and right on the mounting plate J162, the float liquid level sensor J165 can move left and right to fine-tune its position relative to the filter cloth 200, so that it can transmit accurate electrical signals to the drive mechanism J15 to drive the filter cloth 200 to move.

[0052] See also Figure 8 In some embodiments, tension adjustment mechanisms J170 are provided on both the upstream and downstream side walls of the frame J11. These mechanisms include a tension frame J171, a bearing J172 mounted on the tension frame J171, an adjustment nut J174 mounted on the side wall of the bearing J172, and a screw J173 threadedly connected to the adjustment nut J174. The tension frame J171 is provided with a threaded hole threadedly connected to the screw J173. The bearing J172 is rotatably connected to the corresponding end of the driving shaft J153 or the driven shaft J154. In actual use, avoidance holes are provided on both side walls of the frame J11, allowing the shaft to move back and forth within the avoidance holes (the upstream and downstream directions are the front and back directions). To loosen the tension on the driven shaft J154, the screw J173 is rotated, which drives the adjustment nut J174 upstream, causing the bearing J172 welded to the adjustment nut J174 and the driven shaft J154 to move upstream simultaneously. To tighten the tension on the driven shaft J154, the screw J173 is rotated in the opposite direction, causing the driven shaft J154 to rotate downstream. The adjustment operation for the driving shaft J153 is essentially the same as that for the driven shaft J154 and will not be further described here.

[0053] See also Figure 5In some embodiments, a retaining frame J111 is provided downstream of the frame J11, spanning both sides of the frame J11. The distal end of the filter cloth 200 is positioned in the gap between the retaining frame J111 and the bracket J13. The storage portion J14 is located below the retaining frame J111. The retaining frame J111 is provided to position the filter cloth 200, which has trapped sediment, so that it can be accurately placed into the storage portion J14. This prevents the filter cloth 200 from falling outside the storage portion J14, requiring workers to re-store the filter cloth 200. Specifically, to facilitate recycling of used filter cloth 200 by external cleaning companies, the storage portion J14 can be configured as a storage bag. When the storage bag is full, it is replaced with a new one, and the bags filled with filter cloth 200 are tied together and stored in a unified manner. Furthermore, the flat bed filter J10 and the fine grinding filter press J70 may share a storage portion J14 to reduce the workload of recycling the used filter cloth 200 .

[0054] See also Figure 4 In some embodiments, the membrane treatment device 10 includes a raw water tank 101, a sand filter 102, a carbon filter 103, a first safety filter 104, an ultrafiltration device 105, an ultrafiltration water tank 106, a second safety filter 107, a first-level reverse osmosis membrane 108, a first-level reverse osmosis water tank 109, and a second-level reverse osmosis membrane 110, which are connected in sequence; the concentrated water treated by the first-level reverse osmosis membrane 108 flows into the concentrated water collection tank 111, and the concentrated water collection tank 111 is connected to the low-temperature vacuum evaporator 20 through a pipeline; the water treated by the second-level reverse osmosis membrane 110 flows into the water storage tank 30.

[0055] The membrane treatment device 10 operates as follows: Refined wastewater flows through a wastewater lift pump (lift pump 1 shown in the figure) into a sloped bottomed refining settling tank J60. NaOH is added to the refining settling tank J60 to neutralize the wastewater's pH. PAC and PAM are then added to form large alum flakes, which are then removed. The supernatant from the refining settling tank J60 flows into the raw water tank 101. The sludge from the refining settling tank J60 is pumped into the refining filter press J70 via a diaphragm pump for squeezing and dehydration. The effluent from the refining filter press J70 flows back into the water storage tank 30, and the resulting solid hazardous waste can be transported for disposal.

[0056] Water entering the raw water tank 101 is pressurized by a boost pump and then enters a quartz sand filter (shown as sand filter 102) to remove suspended solids that could not be settled in the fine grinding sedimentation tank. The water then enters an activated carbon filter (shown as carbon filter 103), where excess chlorine is adsorbed and some microorganisms are treated. The water exiting the activated carbon filter enters the first safety filter 104 and then the ultrafiltration membrane in the ultrafiltration unit 105 for deep filtration. The ultrafiltration effluent enters the ultrafiltration tank 106. The SDI of the ultrafiltration water is less than 5, meeting the inlet water requirements of the reverse osmosis system.

[0057] The backwash water of the ultrafiltration uses the concentrated water of the secondary reverse osmosis membrane 110 as backwash water for backwashing, and the backwashing wastewater is discharged into the wastewater pool; the backwash water of the sand filter 102 and the carbon filter 103 uses their own inlet water as backwash water, and the backwashing wastewater is discharged into the wastewater pool.

[0058] The water in the ultrafiltration tank 106 is boosted by the reverse osmosis feed pump, then passes through the second safety filter 107 and enters the A membrane high-pressure pump for further pressure boosting. After being treated by the primary reverse osmosis membrane 108, the water enters the primary demineralized water tank (i.e., primary reverse osmosis water tank 109). To prevent scaling and clogging of the primary reverse osmosis membrane 108 and the effects of chloride ions on the membrane, an antiscalant and a reducing agent / fungicide are added at the reverse osmosis feed water outlet. The brine from the primary reverse osmosis membrane 108 is discharged into the brine collection tank 111 for collection and treatment.

[0059] The outlet water of the first-stage reverse osmosis water tank 109 is pressurized by the B membrane high-pressure pump and then enters the second-stage reverse osmosis membrane 110 for desalination treatment. The outlet water enters the water storage tank 30 for reuse, and the concentrated water is discharged into the raw water tank 101.

[0060] See also Figure 4 In some embodiments, the concentrated water collection tank 111 is connected to the tertiary reverse osmosis membrane 112. The water treated by the tertiary reverse osmosis membrane 112 flows through a pipeline to the primary reverse osmosis water tank 109. The concentrated water treated by the tertiary reverse osmosis membrane 112 flows back to the concentrated water collection tank 111.

[0061] The tertiary reverse osmosis membranes 112 primarily desalinate the brine from the brine collection tank 111, thereby increasing wastewater reuse. The brine from the brine collection tank 111 is pressurized by a C-membrane high-pressure pump and then flows into the two tertiary reverse osmosis membranes 112 for desalination. The water produced by the tertiary reverse osmosis membranes 112 flows into the primary reverse osmosis tank 109, where it flows back to the brine collection tank 111, continuously circulating the brine. When the conductivity of the brine collection tank 111 reaches 16 ms / cm, brine processing is suspended.

[0062] When the RO (membrane treatment) water output drops by more than 15%, the pressure drop increases by more than 20%, or the desalination rate drops significantly, the system needs to be chemically cleaned. Therefore, a chemical cleaning pipeline is also installed. Generally, the system should be chemically cleaned every 3 to 6 months of normal operation.

[0063] In summary, the present invention first performs a preliminary sedimentation on the wastewater generated during the fine grinding stage and filters the precipitate. A portion of the resulting recycled water is then reused in the coarse grinding water reservoir C20, while the remaining portion undergoes further purification and filtration. This allows the recycled water with fewer impurities in the coarse grinding water reservoir C20 to be extracted and recycled to the coarse grinding unit C, thereby improving the utilization rate of the recycled water and reducing the load on the wastewater treatment system. The acidic wastewater is first filtered through the flat-bed filter J10. The filtered water flows into the fine grinding circulation tank J20, where it is mixed with the liquid in the preparation tank J30 to form the grinding liquid, which is then reused in the fine grinding unit J. The remaining portion of the filtered water containing the precipitate enters the fine grinding neutralization tank J50 and the fine grinding sedimentation tank J60 for neutralization and purification. The water in the upper layer of the fine grinding sedimentation tank J60 is desalinated by the membrane treatment device 10, while the water in the lower layer is filtered a second time by the fine grinding filter press J70, resulting in recycled water with lower conductivity. This recycled water is then pumped to the water storage tank 30 for future use. The water in the water storage tank 30 can be reused on the grinding head of the fine grinding unit J for cleaning; it can also be reused in the chemical solution tank J30 for preparing grinding fluid; it can also be pumped to the cleaning unit Q for use in the final cleaning process; it can also be used to clean the acid mist tower J80 and replace the water in the acid mist tower J80. A low-temperature vacuum evaporator 20 is provided to evaporate water and concentrate high-boiling-point substances. The acid mist tower J80 is used to neutralize the acid mist generated by the grinding head. A drive mechanism J15 is provided to drive the mesh belt J12 and filter cloth 200 downstream, ensuring that the filter cloth 200 located below the pipe is clean. A U-shaped groove J131 is provided to limit the roller. The rotation of the drive motor J151 drives the mesh belt J12, causing the filter cloth 200, which is tightly attached to the mesh belt J12, to move downstream. A float level sensor J165 is provided to automatically start and stop the drive mechanism J15. The mounting plate J162 and waist-shaped hole J1621 are used to fine-tune the position of the float level sensor J165. A tension adjustment mechanism J170 is used to adjust the tension of the driving shaft J153 or the driven shaft J154. A limit frame J111 is provided to ensure that the filter cloth 200 accurately falls into the storage portion J14.

[0064] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying 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 therefore should not be understood as limiting the present invention.

[0065] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first," "second," or "third" may explicitly or implicitly include one or more of such features. In the description of the present invention, "plurality" means more than two, unless otherwise specifically defined.

[0066] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections, or mutual communication; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0067] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of the present invention, and all such changes or substitutions should fall within the scope of protection of the present invention.

Claims

1. A steel strip grinding and polishing wastewater treatment system, characterized in that: It includes a coarse grinding sedimentation tank, a coarse grinding water storage tank, a coarse grinding lifting pump and a coarse grinding filter press. The upper part of the coarse grinding sedimentation tank is connected to the coarse grinding water storage tank, and the coarse grinding water storage tank reuses water to the coarse grinding unit through the coarse grinding lifting pump. The lower part of the coarse grinding sedimentation tank is connected to the coarse grinding filter press, and the water after solid-liquid separation in the coarse grinding filter press flows back to the coarse grinding water storage tank; the steel belt grinding and polishing wastewater treatment system also includes a flat bed filter, a fine grinding circulation tank, a centrifugal pump, a wastewater storage barrel, a fine grinding neutralization barrel, a fine grinding sedimentation barrel, a fine grinding filter press, and a water storage barrel connected in sequence. The grinding circulation pool is also connected to a preparation water barrel, the water in the upper part of the fine grinding sedimentation barrel and the coarse grinding wastewater in the coarse grinding water storage tank are connected to the membrane treatment device through a pipeline, and the membrane treatment device is connected to the water storage barrel; the water treated by the membrane treatment device and the water treated by the fine grinding filter press are transported to the low-temperature vacuum evaporator through a pipeline, and the water treated by the low-temperature vacuum evaporator is transported to the water storage barrel; it also includes an acid mist tower connected to the water storage barrel, the inlet end of the acid mist tower is connected to the fine grinding unit, and the outlet end of the acid mist tower is connected to the wastewater storage barrel; The coarse grinding filter press, the flat bed filter press and the fine grinding filter press all include a frame, a mesh belt arranged on the frame, a bracket arranged at the upstream of the frame and used to support a roller body around which a filter cloth is wound, a storage portion arranged at the downstream of the frame and used to recover the filter cloth, and a driving mechanism for driving the mesh belt to move the filter cloth toward the downstream direction; the bracket is located at the upstream of the frame; a U-shaped groove is provided on the upper part of the bracket, and the two ends of the roller body around which the filter cloth is wound are respectively arranged in two of the U-shaped grooves; the roller body of the filter cloth is perpendicular to the moving direction of the mesh belt.

2. The steel strip grinding and polishing wastewater treatment system according to claim 1 is characterized in that: It also includes a circulating water pool connected to the cleaning waste water of the cleaning unit through a pipeline, and the outlet end of the circulating water pool is connected to the coarse grinding sedimentation tank.

3. The steel strip grinding and polishing wastewater treatment system according to claim 1, characterized in that: The coarse grinding sedimentation tank is arranged in multiple stages, and adjacent coarse grinding sedimentation tanks are connected by pipes. The distance between the water outlet at the top of each stage and the top of the corresponding coarse grinding sedimentation tank gradually increases, and the corresponding pipe extends into the bottom of the adjacent coarse grinding sedimentation tank.

4. The steel strip grinding and polishing wastewater treatment system according to claim 1, characterized in that: The frame is provided with a mounting bracket spanning both sides of the frame, and a float liquid level sensor is provided on the mounting bracket, and the float liquid level sensor is electrically connected to the driving mechanism; the float liquid level sensor is located downstream of the bracket, and the float liquid level sensor is used to sense the height of the sediment on the filter cloth; the mounting bracket is provided with a support plate, and the support plate is connected to the mounting plate, and the float liquid level sensor is provided on the mounting plate; the mounting plate is provided with a waist-shaped hole extending along its length direction, and the support plate is provided with a locking rod passing through the upper and lower side walls of the support plate, the locking rod passes through the waist-shaped hole, and the end of the locking rod is threadedly connected to a locking nut, and the side wall of the locking nut abuts against the upper end face or the lower end face of the support plate.

5. The steel strip grinding and polishing wastewater treatment system according to claim 1, characterized in that: The membrane treatment device includes a raw water tank, a sand filter, a carbon filter, a first safety filter, an ultrafiltration device, an ultrafiltration water tank, a second safety filter, a first-level reverse osmosis membrane, a first-level reverse osmosis water tank, and a second-level reverse osmosis membrane connected in sequence; the concentrated water treated by the first-level reverse osmosis membrane flows to the concentrated water collection tank, and the concentrated water collection tank is connected to the low-temperature vacuum evaporator through a pipeline; the water treated by the second-level reverse osmosis membrane flows to the water storage tank.

6. The steel strip grinding and polishing wastewater treatment system according to claim 5, characterized in that: The concentrated water collection tank is connected to the three-stage reverse osmosis membrane. The water treated by the three-stage reverse osmosis membrane flows through the pipeline to the first-stage reverse osmosis water tank, and the concentrated water treated by the three-stage reverse osmosis membrane flows back to the concentrated water collection tank.

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