Dust removal water recycling system

Abstract

The utility model discloses a dedusting water recycling system which comprises a sodium chloride dedusting system, a sodium sulfate dedusting system, a reverse osmosis water tank, a sodium chloride raw water tank and a mixed salt dissolving tank, a water inlet of the sodium chloride dust removal system is communicated with the reverse osmosis pool through a water inlet pipe; a valve port of the three-way valve is communicated with a water outlet of the sodium chloride raw water tank; a water outlet of the sodium chloride dust removal system is communicated with a water inlet of the sodium sulfate dust removal system through a water pump; a water outlet of the sodium sulfate dust removal system is communicated with an inlet of the mixed salt dissolving tank. The system has the advantages that reverse osmosis produced water is used for replacing sodium chloride raw water, sodium chloride dust removal water can be continuously used for sodium sulfate dust removal, and then mixed salt is taken for dissolution and does not need to be discharged into a trench, so that the trench wastewater amount of the dust removal system is reduced, the daily operation pressure is relieved, and the reverse osmosis produced water consumption is reduced; and the overall recovery rate of the zero discharge device is improved.

Description

Technical Field:

[0001] The utility model relates to the field of water treatment, and particularly to a dust removal water circulation utilization system. Background Art:

[0002] During the pretreatment of factory wastewater (brine), the water produced by the nanofiltration membrane (NF) enters the sodium chloride raw water tank. The sodium chloride raw water is heated up through a plate heat exchanger, concentrated through a falling film evaporator and a forced circulation evaporator. After the solid-liquid ratio appears, it is sent to a thickener for solid-liquid separation. After the discharge of the thickener, it enters a centrifuge for primary dehydration (water content ≤ 5%). After primary dehydration, it enters a fluidized bed for secondary dehydration (water content ≤ 0.5%). An air intake is arranged at the top of the fluidized bed, and the main purpose is to ensure the smooth circulation of the gas inside the fluidized bed; the liquid separated by the thickener enters the first-effect and second-effect circulation concentration of the mixed salt in sequence, and then enters the mixed salt thickener and centrifuge for solid-liquid separation again, and the salt enters the mixed salt dissolving tank.

[0003] The NF concentrated water enters the sodium sulfate raw water tank. The sodium sulfate raw water is cooled through a freezing tank and a freezing crystallizer, and then sent to a mirabilite thickener for solid-liquid separation. After the discharge of the thickener, it enters a centrifuge for primary dehydration. After primary dehydration, it enters a sulfuric acid hot melt crystallizer, a sulfuric acid thickener, and a sulfuric acid centrifuge for solid-liquid separation, and secondary dehydration is carried out in a fluidized bed. An air intake is also arranged at the top of the fluidized bed; the liquid separated by the sulfuric acid thickener also enters the system of the first-effect and second-effect of the mixed salt, the mixed salt thickener, and the centrifuge. Finally, the salt enters the mixed salt dissolving tank and is dissolved into brine, and then returns to the pretreatment system.

[0004] For the above-mentioned fluidized bed dehydration, a part of the salt dust will enter through the air intake of the fluidized bed along with the gas. If not treated, it will be directly discharged into the atmosphere, causing environmental pollution. Therefore, a dust removal system is set up, and the reverse osmosis water produced by the pretreatment system is used for spraying to form a water curtain. When the salt dust passes through the water curtain, it dissolves in the water to achieve the purpose of dust removal.

[0005] The water curtain water source of the sodium chloride dust removal system comes from the reverse osmosis water produced by the pretreatment system, and the dust removal wastewater returns to the trench. The water curtain water source of the sodium sulfate dust removal system comes from the reverse osmosis water produced by the pretreatment system, and the dust removal wastewater also returns to the trench. These two streams of water cause the increase of the trench water volume and are difficult to treat. Content of the Utility Model:

[0006] The purpose of the utility model is to provide a dust removal water circulation utilization system.

[0007] The utility model is implemented by the following technical solutions:

[0008] A dust removal water circulation utilization system includes a sodium chloride dust removal system, a sodium sulfate dust removal system, a reverse osmosis water tank, a sodium chloride raw water tank, and a mixed salt dissolving tank;

[0009] The water inlet of the sodium chloride dust removal system is communicated with the reverse osmosis water tank through a water inlet pipe;

[0010] A three-way valve is provided on the water inlet pipe, and one valve port of the three-way valve is communicated with the water outlet of the sodium chloride raw water tank;

[0011] The water outlet of the sodium chloride dust removal system is communicated with the water inlet of the sodium sulfate dust removal system through a water pump, and the water outlet of the sodium sulfate dust removal system is communicated with the inlet of the mixed salt dissolution tank.

[0012] Preferably, a flow meter is arranged at the water outlet of the sodium chloride raw water tank, the three-way valve is an electric control valve, and the signal output end of the flow meter is connected with the signal input end of the three-way valve.

[0013] Advantages of the present utility model: Through this system, the water source is replaced from reverse osmosis produced water to sodium chloride raw water, and the sodium chloride dust removal water can be continuously used for sodium sulfate dust removal, and then mixed salt dissolution can be achieved without discharging it to the trench, reducing the trench waste water volume of the dust removal system, alleviating the daily operation pressure, reducing the consumption of reverse osmosis produced water, and improving the overall recovery rate of the zero discharge device; on the other hand, the waste liquid volume of the dust removal system is reduced, and after the waste liquid returns to the pretreatment system, the chloride ion ratio in the inlet water of the pretreatment system can be increased. Description of the drawings:

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present utility model, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0015] Figure 1 It is a schematic diagram of the overall structure of the present utility model.

[0016] In the figure: sodium chloride dust removal system 1, sodium sulfate dust removal system 2, reverse osmosis water tank 3, sodium chloride raw water tank 4, mixed salt dissolution tank 5, water inlet pipe 6, three-way valve 7, water pump 8, flow meter 9. Specific embodiments:

[0017] The following will clearly and completely describe the technical solutions in the embodiments of the present utility model with reference to the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, rather than all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present utility model.

[0018] Such asFigure 1 As shown in the figure, a dust removal water circulation utilization system includes a sodium chloride dust removal system 1, a sodium sulfate dust removal system 2, a reverse osmosis water tank 3, a sodium chloride raw water tank 4, and a mixed salt dissolution tank 5;

[0019] The water inlet of the sodium chloride dust removal system 1 is connected to the reverse osmosis water tank 3 through a water inlet pipe 6; the water in the reverse osmosis water tank 3 is supplied to the sodium chloride dust removal system 1 through the water inlet pipe 6 and used as dust removal spray water.

[0020] A three-way valve 7 is provided on the water inlet pipe 6, and one valve port of the three-way valve 7 is connected to the water outlet of the sodium chloride raw water tank 4; the three-way valve 7 can be reversed to connect the sodium chloride raw water tank 4 with the sodium chloride dust removal system 1. The sodium chloride raw water is an unsaturated solution, and the chloride ion content is generally about 32000 mg / l. The sodium chloride raw water in the sodium chloride raw water tank 4 can be used as sodium chloride dust removal water.

[0021] The water outlet of the sodium chloride dust removal system 1 is connected to the water inlet of the sodium sulfate dust removal system 2 through a water pump 8, and the water outlet of the sodium sulfate dust removal system 2 is connected to the inlet of the mixed salt dissolution tank 5. After the sodium chloride raw water is used for dust removal in the sodium chloride dust removal system 1, the chloride ion content is about 54000 mg / l and the sulfate ion content is about 3200 mg / l, which can be used as dust removal water for the sodium sulfate dust removal system 2. It enters the sodium sulfate dust removal system 2 again through the water pump 8 for dust removal, and the sodium sulfate dust removal waste liquid enters the mixed salt dissolution tank 5 to be used as mixed salt dissolution brine and returns to the pretreatment system after being fully dissolved.

[0022] A flow meter 9 is provided at the water outlet of the sodium chloride raw water tank 4. The three-way valve 7 is an electrically controlled valve, and the signal output end of the flow meter 9 is connected to the signal input end of the three-way valve 7. When the flow meter 9 monitors that there is no sodium chloride raw water, the three-way valve 7 is switched to the reverse osmosis water tank 3 to use the water in the reverse osmosis water tank 3 to ensure the normal operation of the dust removal process.

[0023] Working principle: When the present utility model is in use, the three-way valve 7 is reversed to connect the sodium chloride raw water tank 4 with the sodium chloride dust removal system 1. The sodium chloride raw water is an unsaturated solution, and the chloride ion content is generally about 32000 mg / l. The sodium chloride raw water in the sodium chloride raw water tank 4 can be used as sodium chloride dust removal water. After the sodium chloride raw water is used for dust removal in the sodium chloride dust removal system 1, the chloride ion content is about 54000 mg / l and the sulfate ion content is about 3200 mg / l, which can be used as dust removal water for the sodium sulfate dust removal system 2. It enters the sodium sulfate dust removal system 2 again through the water pump 8 for dust removal, and the sodium sulfate dust removal waste liquid enters the mixed salt dissolution tank 5 to be used as mixed salt dissolution brine and returns to the pretreatment system after being fully dissolved.

[0024] In this system, the reverse osmosis product water is used to replace the sodium chloride raw water for the water source, and the sodium chloride dust removal water can continue to be used for sodium sulfate dust removal. Then, mixed salts are obtained for dissolution without discharging them into the trench, reducing the amount of trench wastewater in the dust removal system, alleviating the daily operation pressure, reducing the consumption of reverse osmosis product water, and increasing the overall recovery rate of the zero-discharge device. On the other hand, the amount of waste liquid in the dust removal system is reduced. After the waste liquid is returned to the pretreatment system, the ratio of chloride ions to sulfate ions in the influent of the pretreatment system can be increased from 3:1 to 5:1.

[0025] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A dust removal water recycling system, characterized in that: Including sodium chloride dust removal system, sodium sulfate dust removal system, reverse osmosis water pool, sodium chloride raw water pool, mixed salt dissolution tank; The water inlet of the sodium chloride dust removal system is connected to the reverse osmosis water tank through a water inlet pipe; The water inlet pipe is provided with a three-way valve, one valve port of the three-way valve is connected to the water outlet of the sodium chloride raw water tank; The water outlet of the sodium chloride dust removal system is connected to the water inlet of the sodium sulfate dust removal system through a water pump, and the water outlet of the sodium sulfate dust removal system is connected to the inlet of the mixed salt dissolution tank.

2. A dust removal water recycling system according to claim 1, characterized in that: A flow meter is arranged on the water outlet of the sodium chloride raw water pool, the three-way valve is an electrically controlled valve, and the signal output end of the flow meter is connected to the signal input end of the three-way valve.

Images