CN217051894U - Treatment system for industrial wastewater containing trace nitrate and nitrite - Google Patents

Abstract

The utility model relates to a sewage treatment technical field especially relates to a contain trace nitrate, nitrite industrial waste water's processing system, including the hardness reduction unit that is used for reducing waste water quality hardness that sets gradually, a filter unit for filtering the edulcoration, a manganese sand de-ironing separator for getting rid of soluble iron ion in the waste water, carry out the ion exchange through anion exchange resin and detach the ion exchanger of nitrate and nitrite that contains in the quality of water, still including the clean water basin that is used for storing the clear water after ion exchanger handles, a sewage pond for storing manganese sand de-ironing separator and ion exchanger discharge sewage. The percentage of the clear water obtained after treatment can reach 95 percent, the percentage of the discharged sewage is less than 5 percent, the treatment rate and the removal rate of the sewage with low-concentration ions are high, and the high recycling rate can be achieved; the content of nitrate and nitrite in the treated clean water can be reduced to below 10mg/L, and the treated wastewater does not contain chloride ions and does not corrode stainless steel equipment when being recycled.

Description

Treatment system for industrial wastewater containing trace nitrate and nitrite

Technical Field

The utility model relates to the field of industrial wastewater treatment, in particular to a treatment system for industrial wastewater containing trace nitrate and nitrite.

Background

The production sewage can be discharged after reaching the standard after being treated, and if the industrial wastewater containing trace nitrate and nitrite enters other production systems for recycling, the industrial wastewater is enriched for a long time, which is easy to cause environmental protection or safety accidents. How to efficiently remove trace nitrate and nitrite contained in sewage, reduce the sewage amount, improve the utilization rate of water and reduce the pressure of industrial production water balance becomes an important task to be solved urgently.

At present, industrial wastewater is treated by a reverse osmosis method, the reverse osmosis method has better removal rate when used for treating high-concentration ion sewage, and if the reverse osmosis method is used for treating low-concentration industrial wastewater with nitrate content of less than or equal to 400mg/L and nitrite content of less than or equal to 150mg/L, the method has the following four defects: 1. the reverse osmosis treatment rate is low, the proportion of discharged concentrated water is 30-50%, and a large amount of wastewater is still generated after treatment; 2. the removal rate of the sewage with low-concentration ions is very low; 3. the internal clearance of the reverse osmosis membrane equipment is small, so that the reverse osmosis membrane equipment is easy to block and inconvenient to clean; 4. after the reverse osmosis membrane is polluted, hydrochloric acid and sodium hydroxide are needed to carry out regeneration treatment, and the treated wastewater contains chloride ions and is used for easily corroding stainless steel equipment in the recycling chemical production process, and simultaneously influencing the main content of products to cause unqualified product quality. Therefore, there is a great need for improvements and optimizations to the prior art.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a processing system who contains trace nitrate, nitrite industrial waste water to solve nitrate content and be less than or equal to 400mg/L, nitrite content and be less than or equal to 150 mg/L's low concentration industrial waste water treatment problem, reach and handle back nitrate content and be less than or equal to 10mg/L, nitrous acid is less than or equal to 10mg/L, produce less sewage simultaneously, improve the water utilization ratio, reduce water balance pressure.

In order to solve the technical problem, the utility model discloses the technical scheme who takes does:

contain the processing system of trace nitrate, nitrite industrial waste water, including what set gradually be used for reducing the waste water quality hardness of water fall the hardness unit, be used for filtering the filter unit of edulcoration, be arranged in getting rid of the manganese sand de-ironing separator of the dissolubility iron ion in the waste water, carry out the ion exchange through anion exchange resin and detach the ion exchanger of the nitrate that contains and nitrite in the quality of water, still including the clean water basin that is used for storing the clear water behind the ion exchanger handles, be used for storing the sewage basin of manganese sand de-ironing separator and ion exchanger discharge sewage.

Furthermore, the hardness reducing unit comprises a first regulating reservoir and a second regulating reservoir, wherein the first regulating reservoir is used for reducing the hardness of water by adding liquid caustic soda, the second regulating reservoir is used for regulating the PH value of the wastewater by introducing carbon dioxide gas, and the PH value of the wastewater is regulated to 7.5-8.5 by the second regulating reservoir.

Furthermore, the filtering unit comprises a first cloth bag filter and a second cloth bag filter, and a lifting pump for lifting the pressure of the wastewater is further arranged between the hardness reducing unit and the first cloth bag filter.

Furthermore, the manganese sand iron remover is connected with a backwashing pipe, and the backwashing pipe can supply water to backwash the manganese sand iron remover through the clean water tank.

Furthermore, the ion exchanger comprises a first ion exchanger and a second ion exchanger, and the first ion exchanger and the second ion exchanger are both connected with a backwashing pipe for backwashing, a caustic soda liquid pipe for regenerating the anion exchange resin and a forward washing pipe for washing away residual sodium hydroxide in the anion exchange resin.

Furthermore, a heat exchange device used for reducing the water temperature is arranged between the filtering unit and the manganese sand iron remover.

Furthermore, the heat exchange device comprises a first-stage heat exchanger for exchanging heat by adopting self-contained circulating water and a second-stage heat exchanger for exchanging heat by adopting circulating water for supplementing water.

Compared with the prior art, the beneficial effects of the utility model are that: when in treatment, the industrial wastewater containing nitrate and nitrite is treated by the hardness reducing unit to reduce the hardness of the wastewater, then the wastewater is filtered and purified by the filtering unit to remove impurities and precipitates in water quality, then the manganese sand iron remover is used for filtering and removing soluble iron ions in the water quality by adopting manganese sand, finally the treated wastewater enters the ion exchanger to carry out ion exchange with anion exchange resin in the ion exchanger, and nitrate and nitrite in the water quality are removed by ion exchange; the clean water treated by the ion exchanger is discharged into a clean water tank, can enter a circulating water system to be supplemented as soft water, or enter a waste heat boiler to be supplemented as boiler water, or enter a production system to be recycled, and the sewage discharged by the manganese sand iron remover and the ion exchanger is discharged into a sewage tank to be stored. The proportion of the clear water obtained after treatment can reach 95 percent, the proportion of the discharged sewage is less than 5 percent, namely 95 percent of the waste water can enter a circulating water system to be supplemented as soft water after treatment, or enter a waste heat boiler to be supplemented as boiler water, or enter a production system to be recycled, the treatment rate and the removal rate of the sewage with low-concentration ions are high, the high recycling rate can be achieved, and the generated waste water is little; and the content of nitrate and nitrite in the treated clean water can be reduced to below 10mg/L, the environmental protection requirement of sewage treatment can be met, a series of possible safety and environmental protection problems are avoided, meanwhile, the treated waste water does not contain chloride ions, stainless steel equipment cannot be corroded during recycling, and the influence on the main content of products and the quality of the products is avoided. In addition, the treatment system has simple structure, is not easy to block and is convenient to clean and regenerate.

Drawings

Fig. 1 is a system architecture diagram according to an embodiment of the present invention.

Detailed Description

The following further describes the embodiments of the present invention. It should be noted that the description of the embodiments is provided to help understanding of the present invention, but the present invention is not limited thereto. In addition, the technical features related to the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Referring to fig. 1, the treatment system of the embodiment is used for treating industrial wastewater containing nitrate and nitrite, and includes a hardness reducing unit 10 for reducing the hardness of the wastewater, a filtering unit 20 for filtering and removing impurities, a manganese sand iron remover 30 for removing soluble iron ions in the wastewater, an ion exchanger 40 for removing nitrate and nitrite contained in the water through ion exchange by anion exchange resin, a clean water tank for storing clean water treated by the ion exchanger 40, and a sewage tank for storing sewage discharged by the manganese sand iron remover 30 and the ion exchanger 40.

During treatment, firstly, the industrial wastewater containing nitrate and nitrite is treated by the hardness reducing unit 10 to reduce the hardness of the wastewater, then the wastewater is filtered and purified by the filtering unit 20 to remove impurities and sediments in water, then the manganese sand iron remover 30 is used for filtering and removing soluble iron ions in the water by manganese sand, finally the treated wastewater enters the ion exchanger 40 to carry out ion exchange with anion exchange resin in the ion exchanger 40, and the nitrate and nitrite in the water are removed by the ion exchange; the clean water treated by the ion exchanger 40 is discharged into a clean water tank, and can enter a circulating water system to be supplemented as soft water, or enter a waste heat boiler to be supplemented as boiler water, or enter a production system to be recycled, and the sewage discharged by the manganese sand iron remover 30 and the ion exchanger 40 is discharged into a sewage tank to be stored.

The percentage of clean water obtained after the treatment can reach 95 percent, the percentage of discharged sewage is about 5 percent, namely 95 percent of the wastewater can enter a circulating water system to be supplemented as soft water after being treated, or enter a waste heat boiler to be supplemented as boiler water, or enter a production system to be recycled, and the recycling rate of water is high. And the content of nitrate and nitrite in the treated clean water can be reduced to below 10mg/L, so that the environmental protection requirement of sewage treatment can be met, and a series of safety and environmental protection problems possibly brought about are avoided. In addition, the treatment system has simple structure, is not easy to block, is convenient to clean and regenerate and is convenient to realize automatic control.

In some embodiments, the hardness reducing unit 10 comprises a first adjusting tank 11 for reducing the hardness of water by adding liquid alkali and a second adjusting tank 12 for adjusting the pH value by introducing carbon dioxide gas, wherein the second adjusting tank 12 adjusts the pH value of the wastewater to 8; when in treatment, the industrial wastewater containing nitrate and nitrite is discharged into a first regulating tank 11, a certain amount of liquid alkali is introduced, the liquid alkali is fully mixed and precipitated, and the water hardness is reduced, mainly the content of calcium ions and magnesium ions is reduced; and discharging the wastewater with the reduced hardness into a second regulating tank 12, introducing carbon dioxide gas, and regulating the pH value to about 8 to make the wastewater alkaline so as to facilitate subsequent treatment.

In order to facilitate adding liquid caustic soda and carbon dioxide gas, a liquid caustic soda adding device and a carbon dioxide pipeline are respectively configured in the first regulating reservoir 11 and the second regulating reservoir 12 of the embodiment, the carbon dioxide pipeline is connected with a carbon dioxide gas source, and the carbon dioxide gas source can be a carbon dioxide gas storage tank or a carbon dioxide preparation device.

In some embodiments, the filtering unit 20 includes a first cloth filter 21 and a second cloth filter 22, and a lift pump 23 for raising the pressure of the waste water is further disposed between the hardness-reducing unit 10 and the first cloth filter 21. Specifically, the lift pump 23 pumps the wastewater with the adjusted PH value out of the second adjusting tank, pressurizes the wastewater, and sends the wastewater to the first cloth bag filter 21 and the second cloth bag filter 22 for filtering twice, the first cloth bag filter 21 and the second cloth bag filter 22 have different filtering precisions, wherein the filtering precision of the second cloth bag filter 22 is higher than that of the first cloth bag filter 21, and impurities and precipitates in the water can be effectively removed through two stages of cloth bag filtering with different precisions.

In some embodiments, the manganese sand iron remover 30 is connected with a backwashing pipe 31, the backwashing pipe 31 can supply water to backwash the manganese sand iron remover 30 through a clean water tank, and the regeneration of the manganese sand iron remover can be realized through backwashing, so that the service cycle is prolonged, and the operation cost is reduced.

In some embodiments, the ion exchanger 40 includes a first ion exchanger 41 and a second ion exchanger 42, and the sewage treated by the foregoing processes is treated by the two ion exchangers simultaneously, so that the treatment efficiency is greatly improved, the clean water treated by the first ion exchanger 41 and the second ion exchanger 42 is discharged into the clean water tank through the clean water pipe 43, and the sewage is discharged into the sewage tank through the sewage pipe 44.

In the present embodiment, a backwash pipe for backwashing, a caustic pipe for regenerating the anion exchange resin, and a forward wash pipe for washing off residual sodium hydroxide in the anion exchange resin are connected to each of the first ion exchanger 41 and the second ion exchanger 42. After the two ion exchangers run for a certain time, the ion exchangers can be backwashed through a backwash pipe, and then the anion exchange resin is regenerated through a liquid alkali pipe by adopting liquid alkali; and finally, washing the resin through a washing tube to remove residual sodium hydroxide in the resin. The back washing pipe, the liquid caustic soda pipe and the forward washing pipe are respectively provided with a back washing pump, a liquid caustic soda pump and a forward washing pump so as to connect the back washing pump, the liquid caustic soda pump and the forward washing pump with the PLC and the DCS, the PLC is used for realizing field control and remote automatic operation of the DCS, and the discharged sewage can enter the production system of the workshop for recycling.

In some embodiments, a heat exchange device 50 for reducing the temperature of water is further disposed between the filter unit 20 and the manganese sand iron remover 30. Specifically, the heat exchange device 50 comprises a first-stage heat exchanger 51 for exchanging heat by using self-contained circulating water and a second-stage heat exchanger 52 for exchanging heat by using circulating water for supplementing water, and after two-stage heat exchange, the water temperature can be reduced to a proper temperature for subsequent direct recycling.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. It will be apparent to those skilled in the art that various changes, modifications, substitutions and alterations can be made in the embodiments without departing from the principles and spirit of the invention, and the scope of the invention is to be accorded the full scope of the claims.

Claims (7)

1. The treatment system for the industrial wastewater containing the trace nitrate and the nitrite is characterized by comprising a hardness reducing unit (10) for reducing the water hardness of the wastewater, a filtering unit (20) for filtering and removing impurities, a manganese sand iron remover (30) for removing soluble iron ions in the wastewater, an ion exchanger (40) for removing nitrate and nitrite contained in the water through ion exchange by anion exchange resin, a clear water tank for storing clear water treated by the ion exchanger (40), and a sewage tank for storing sewage discharged by the manganese sand iron remover (30) and the ion exchanger (40), which are sequentially arranged.

2. The system for treating industrial wastewater containing micro nitrate and nitrite according to claim 1, wherein the hardness reducing unit (10) comprises a first adjusting tank (11) for reducing the water hardness by adding liquid alkali and a second adjusting tank (12) for adjusting the pH value by introducing carbon dioxide gas, and the second adjusting tank (12) adjusts the pH value of the wastewater to 7.5-8.5.

3. The system for treating industrial wastewater containing micro nitrate and nitrite according to claim 1, wherein the filtering unit (20) comprises a first cloth bag filter (21) and a second cloth bag filter (22), and a lift pump (23) for raising the pressure of wastewater is further arranged between the hardness reducing unit (10) and the first cloth bag filter (21).

4. The system for treating industrial wastewater containing trace nitrate and nitrite according to claim 1, wherein the manganese sand iron remover (30) is connected with a backwashing pipe (31), and the backwashing pipe (31) can backwash the manganese sand iron remover (30) through the clean water tank.

5. The system for treating industrial wastewater containing trace nitrate and nitrite according to claim 1, wherein the ion exchanger (40) comprises a first ion exchanger (41) and a second ion exchanger (42), and a backwash pipe for backwashing, a caustic pipe for regenerating the anion exchange resin and a forward washing pipe for washing away residual sodium hydroxide in the anion exchange resin are connected to each of the first ion exchanger (41) and the second ion exchanger (42).

6. The system for treating industrial wastewater containing trace nitrate and nitrite as claimed in any one of claims 1 to 5, wherein a heat exchange device (50) for reducing water temperature is further arranged between the filtering unit (20) and the manganese sand iron remover (30).

7. The system for treating industrial wastewater containing trace nitrate and nitrite as claimed in claim 6, wherein the heat exchange device (50) comprises a primary heat exchanger (51) for exchanging heat with self-contained circulating water and a secondary heat exchanger (52) for exchanging heat with supplemented water of circulating water.

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