Zinc smelting wastewater environmental protection treatment system

Abstract

The utility model relates to smelting sewage treatment technical field, the utility model provides a kind of zinc smelting sewage environmental protection treatment system, sewage pool, sewage pool top is equipped with inlet, the outlet of deslagging of being equipped with by first spiral deslagging machine in the lower side wall of sewage pool, sewage pool lower side is connected with adjusting pool after first filter screen, adjusting pool lower side is connected with anoxic tank after second filter screen, anoxic tank one end lower side is connected with oxygen tank after third filter screen, oxygen tank is connected with air blower, residue in the bottom of oxygen tank is discharged to sludge pool through the outlet of sludge of oxygen tank side wall opening by second spiral deslagging machine, oxygen tank lower side is connected with MBR reaction pool after fourth filter screen, MBR reaction pool is connected with the clean water pool being arranged below by clean water pipe, utilize the link of step-by-step purification formed by gravity effect, ensure that sewage is in turn through physical deslagging, water quality adjustment, biological denitrification and phosphorus removal, membrane separation treatment link, reduce energy consumption and floor area, ensure the purification treatment efficiency and water quality stability of sewage.

Description

Technical Field

[0001] This utility model relates to the field of smelting wastewater treatment technology, and more specifically, to an environmentally friendly wastewater treatment system for zinc smelting. Background Technology

[0002] Zinc smelting, as a crucial basic industry, generates large amounts of wastewater containing heavy metal ions (such as zinc, lead, and cadmium), acidic substances, and complex organic matter during its production process. If this wastewater is discharged directly without effective treatment, it will cause irreversible pollution to soil, water bodies, and the ecological environment, threatening human health and ecological security.

[0003] Currently, the main treatment processes for zinc smelting wastewater include traditional activated sludge processes, anaerobic biological treatment processes, and biofilm processes. While the traditional activated sludge process is widely used, it suffers from high investment costs, high operating expenses, and large land area requirements. Furthermore, the sludge treatment process is complex and requires supporting anaerobic digestion facilities. Anaerobic biological treatment technology, although capable of degrading some organic matter, has limited treatment efficiency, and the effluent quality often fails to meet high discharge standards. It also has drawbacks such as large land area requirements and difficulties in collecting and treating waste gas. The biofilm process offers advantages such as ease of maintenance, energy saving, and low sludge production, but when high effluent quality requirements are needed, additional advanced treatment stages are required, leading to increased overall investment costs. In summary, existing treatment technologies generally suffer from relatively large land areas, low wastewater purification efficiency, and poor water quality stability, making it difficult to achieve efficient and economical deep purification and stable compliance with discharge standards for zinc smelting wastewater. Utility Model Content

[0004] The purpose of this invention is to provide an environmentally friendly wastewater treatment system for zinc smelting, which solves the problems of large footprint, low wastewater purification efficiency, and poor water quality stability of traditional zinc smelting wastewater treatment systems.

[0005] This utility model is achieved through the following technical solution: an environmentally friendly wastewater treatment system for zinc smelting, including a wastewater tank, an inlet at the top of the wastewater tank, a slag outlet on the lower side wall of the wastewater tank for slag removal by a first spiral slag remover, an equalization tank connected to the bottom of the wastewater tank after passing through a first filter screen, an anoxic tank connected to the bottom of the equalization tank after passing through a second filter screen, an aerobic tank connected to the bottom of one end of the anoxic tank after passing through a third filter screen, a blower connected to the aerobic tank, and slag at the bottom of the aerobic tank being discharged to a sludge tank through a sludge outlet on the side wall of the aerobic tank by a second spiral slag remover, and an MBR reactor connected to the bottom of the aerobic tank after passing through a fourth filter screen, the MBR reactor being connected to a clear water tank below it through a clear water pipe.

[0006] Furthermore, the clear liquid in the upper layer of the equalization tank is filtered by a vacuum filter and then introduced into the clear water tank.

[0007] Furthermore, a spray pipe connected to a vacuum filter is installed at the top of the clear water tank for cleaning the tank walls.

[0008] Furthermore, the spray pipes are arranged in a horizontal ring along the inner wall of the clear water tank.

[0009] Furthermore, a denitrification agent tank is installed in the anoxic tank.

[0010] Furthermore, a flocculant addition box is installed in the aerobic tank.

[0011] Furthermore, several activated carbon adsorption columns are evenly distributed within the MBR reactor.

[0012] Furthermore, the mesh size of the first, second, third, and fourth filters gradually increases.

[0013] This utility model has at least the following advantages and beneficial effects:

[0014] (1) By rationally connecting the sewage tank, equalization tank, anoxic tank, aerobic tank, MBR reactor and clear water tank in layers, a step-by-step purification chain is formed by gravity, ensuring that the sewage passes through key treatment links such as physical slag removal, water quality adjustment, biological nitrogen and phosphorus removal, and membrane separation in sequence, effectively reducing energy consumption and land area, and ensuring the purification efficiency and water quality stability of the sewage.

[0015] (2) The upper layer of clear water in the equalization tank is drawn out through a vacuum filter. After filtration, the tank wall of the clear water tank is flushed and cleaned to reduce the treatment load of the MBR reactor, avoid the safety risks of manual cleaning, and improve the convenience of operation and maintenance.

[0016] (3) By filtering through the first, second, third and fourth filters, a gradient filtration system is formed to avoid clogging of a single filter due to excessive load and to improve the stability of the filtration system. Attached Figure Description

[0017] Figure 1 This utility model provides a schematic diagram of the layout of an environmentally friendly wastewater treatment system for zinc smelting.

[0018] Attached diagram labels: 1-Wastewater tank, 10-Inlet, 11-Sludge outlet, 12-First spiral sludge remover, 13-First filter screen, 2-Equalization tank, 21-Second filter screen, 3-Anoxic tank, 31-Third filter screen, 32-Denitrification agent tank, 4-Aerobic tank, 40-Sludge outlet, 41-Blower, 42-Second spiral sludge remover, 43-Fourth filter screen, 44-Flocculant addition tank, 5-Sludge tank, 6-MBR reactor, 60-Clear water pipe, 61-Activated carbon adsorption column, 7-Clear water tank, 71-Spray pipe, 8-Vacuum filter. Detailed Implementation

[0019] The specific implementation method is described below with reference to the accompanying drawings.

[0020] Example

[0021] like Figure 1 As shown in this embodiment, a zinc smelting wastewater environmental protection treatment system is disclosed, including a wastewater tank 1. The top of the wastewater tank 1 is provided with an inlet 10. The lower side wall of the wastewater tank 1 is provided with a slag outlet 11 for slag discharge through a first spiral slag remover 12. The wastewater tank 1 is connected to an equalization tank 2 after passing through a first filter screen 13. The equalization tank 2 is connected to an anoxic tank 3 after passing through a second filter screen 21. The lower part of one end of the anoxic tank 3 is connected to an aerobic tank 4 after passing through a third filter screen 31. The aerobic tank 4 is connected to a blower 41. The residue at the bottom of the aerobic tank 4 is discharged to a sludge tank 5 through a sludge outlet 40 opened on the side wall of the aerobic tank 4 by a second spiral slag remover 42. The aerobic tank 4 is connected to an MBR reactor 6 after passing through a fourth filter screen 43. The MBR reactor 6 is connected to a clear water tank 7 set below it through a clear water pipe 60. Specifically, the inlet 10 at the top of wastewater tank 1 receives zinc smelting wastewater, and a first spiral slag remover 12 is installed at its lower part. The first spiral slag remover 12 consists of a motor and spiral blades, used to push the residue deposited at the bottom of wastewater tank 1 towards the slag outlet 11 for discharge, achieving preliminary solid-liquid separation and preventing subsequent filter screen clogging. After being filtered by the first filter screen 13, the wastewater enters the equalization tank 2 below wastewater tank 1 to regulate the water quality and quantity, balancing the uneven wastewater quality (such as heavy metal concentration and pH value) and quantity caused by day-night production fluctuations, avoiding impact on subsequent treatment units, and providing system stability. Then, the wastewater flows downward through the second filter screen 21 into the anoxic tank 3, which is in a low-aeration environment, for denitrification. Using organic matter in the wastewater or an added carbon source, denitrifying bacteria convert nitrate nitrogen into nitrogen gas. After denitrification treatment, the wastewater enters the aerobic tank 4 from the lower part of one side of the anoxic tank 3, passing through the third filter screen 31. The aerobic tank 4 is supplied with sufficient oxygen by a blower 41, utilizing aerobic microorganisms to degrade organic matter. A second spiral sludge remover 42, also composed of a motor and spiral blades, is installed at the bottom of the aerobic tank 4 to discharge the remaining sludge after biological treatment, achieving continuous sludge cleaning and reducing manual intervention. The treated water enters the MBR reactor 6 after being filtered through the fourth filter screen 43 at the bottom. Combining membrane separation (ultrafiltration membrane) with the bioreactor, the membrane module traps microbial flocs and large molecular pollutants, achieving efficient sludge-water separation, and the effluent quality meets reuse standards. By rationally connecting the wastewater tank 1, equalization tank 2, anoxic tank 3, aerobic tank 4, MBR reactor 6, and clear water tank 7 in a layered manner, a step-by-step purification chain is formed by utilizing gravity. This ensures that the wastewater passes through key treatment stages such as physical sludge removal, water quality adjustment, biological nitrogen and phosphorus removal, and membrane separation in sequence, effectively reducing energy consumption and land area, and ensuring the efficiency of wastewater purification and water quality stability.

[0022] Furthermore, in a specific implementation, the upper clear liquid in the equalization tank 2 provided in this embodiment of the invention is drawn into the clear water tank 7 after being filtered by the vacuum filter 8. Specifically, the vacuum filter 8 can adopt existing technology and consists of a filter cloth, a vacuum pump, and a filter chamber. The vacuum pump generates negative pressure, drawing the upper clear liquid from the equalization tank 2 through the filter cloth and trapping fine suspended solids. The negative pressure environment accelerates the filtration rate, reduces the treatment load on the MBR reactor 6, and extends the membrane cleaning cycle. The vacuum filter 8 can be installed in the cavity between the upper part of the MBR reactor 6 and the side of the aerobic tank 4, reducing the occupied area.

[0023] Preferably, a spray pipe 71 connected to a vacuum filter 8 is installed at the top of the clear water tank 7 for cleaning the tank wall. Specifically, the spray pipe 71 is arranged in a horizontal ring along the inner wall of the clear water tank 7. The spray pipe 71 is made of stainless steel. The clear water filtered by the vacuum filter 8 has a high water pressure, which can be used to flush and clean the tank wall through the evenly distributed nozzles on the spray pipe 71. This can remove impurities such as calcium and magnesium ions and microbial mucus attached to the wall of the clear water tank 7, avoid the safety risks of manual cleaning, and improve the convenience of operation and maintenance.

[0024] Furthermore, in specific implementation, a denitrification agent tank 32 is provided within the anoxic tank 3 provided in this embodiment of the invention. Specifically, the volume of the denitrification agent tank 32 is designed according to the wastewater flow rate, and it is equipped with a flow metering pump (such as an electromagnetic diaphragm pump) to automatically add carbon source agents (such as methanol and sodium acetate) based on the online monitored nitrate nitrogen concentration, controlling the carbon-to-nitrogen ratio (C / N) of the anoxic tank 3 to be 4-6:1. This solves the common problem of insufficient carbon source in zinc smelting wastewater (such as low organic matter content in industrial wastewater), ensuring that the denitrification reaction proceeds fully.

[0025] Furthermore, in specific implementation, a flocculant addition tank 44 is provided in the aerobic tank 4 provided in this embodiment of the present invention. Specifically, the flocculant addition tank 44 can be made of corrosion-resistant material (such as PE plastic), and stores PAC (polyaluminum chloride) or PAM (polyacrylamide). It is quantitatively added to the aerobic tank 4 by a screw pump. The flocculant causes colloidal particles in the sewage to aggregate into large flocs through charge neutralization and bridging. Combined with the MBR membrane filtration of the subsequent MBR reactor 6, it reduces suspended solids and effluent turbidity.

[0026] Furthermore, in a specific implementation, a plurality of activated carbon adsorption columns 61 are evenly distributed within the MBR reactor 6 provided in this embodiment of the present invention. Specifically, the activated carbon adsorption columns 61 are made of granular activated carbon, filled within a detachable frame, and evenly arranged within the MBR reactor 6. They purify wastewater through a dual process of physical adsorption (microporous structure) and biodegradation (attached microorganisms). The activated carbon adsorption does not interfere with the membrane module within the MBR reactor 6. The adsorption columns retain large molecular pollutants before the membrane module, reducing membrane surface contamination, extending the membrane cleaning cycle, and lowering the membrane replacement frequency.

[0027] Furthermore, in specific implementations, the mesh size of the first filter 13, second filter 21, third filter 31, and fourth filter 43 provided in this embodiment of the present invention gradually increases. Specifically, the first filter 13, second filter 21, third filter 31, and fourth filter 43 are all made of stainless steel. The first filter 13 can use an 80-mesh filtration to intercept coarse suspended particles; the second filter 21 can use a 120-mesh filtration to further trap fine impurities; the third filter 31 can use a 150-mesh filtration to prevent the loss of biological packing material; and the fourth filter 43 can use a 200-mesh filtration to ensure that the wastewater entering the MBR is free of large particles, thus extending the membrane module's lifespan. The first filter 13, second filter 21, third filter 31, and fourth filter 43 form a gradient filtration system, avoiding clogging of a single filter due to excessive load and improving the stability of the filtration system.

Claims

1. An environmentally friendly wastewater treatment system for zinc smelting, characterized in that, The system includes a sewage tank (1), with an inlet (10) at the top and a slag outlet (11) on the lower side wall for slag removal by a first spiral slag remover (12). Below the sewage tank (1), a regulating tank (2) is connected via a first filter screen (13). Below the regulating tank (2), an anoxic tank (3) is connected via a second filter screen (21). One end of the anoxic tank (3) is connected via a third filter screen (31). There is an aerobic tank (4), which is connected to a blower (41). The residue at the bottom of the aerobic tank (4) is discharged to the sludge tank (5) through the sludge outlet (40) opened on the side wall of the aerobic tank (4) by the second spiral sludge remover (42). The aerobic tank (4) is connected to an MBR reactor (6) below it through a fourth filter screen (43). The MBR reactor (6) is connected to the clear water tank (7) set below it through a clear water pipe (60).

2. The environmental protection system for zinc smelting wastewater treatment according to claim 1, characterized in that, The clear liquid in the upper layer of the regulating tank (2) is drawn and filtered by the vacuum filter (8) and then introduced into the clear water tank (7).

3. The environmental protection system for zinc smelting wastewater treatment according to claim 2, characterized in that, The top of the clear water tank (7) is equipped with a spray pipe (71) connected to the vacuum filter (8) for cleaning the tank wall of the clear water tank (7).

4. The environmental protection system for treating zinc smelting wastewater according to claim 3, characterized in that, The spray pipe (71) is arranged in a horizontal ring along the inner wall of the clear water pool (7).

5. The environmental protection system for treating zinc smelting wastewater according to claim 1, characterized in that, The anoxic tank (3) is equipped with a denitrification agent tank (32).

6. The environmental protection system for treating zinc smelting wastewater according to claim 1, characterized in that, The aerobic tank (4) is equipped with a flocculant addition box (44).

7. The environmental protection system for treating zinc smelting wastewater according to claim 1, characterized in that, The MBR reactor (6) is equipped with several activated carbon adsorption columns (61) evenly distributed within it.

8. The environmental protection system for treating zinc smelting wastewater according to claim 1, characterized in that, The mesh counts of the first filter (13), the second filter (21), the third filter (31), and the fourth filter (43) gradually increase.

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