CN205420021U - System for handle desulfurization waste water resource recovery in coordination - Google Patents

Abstract

The utility model discloses a system for handle desulfurization waste water resource recovery in coordination, including desulfurization waste water input pipeline, pH equalizing basin, reaction air supporting pond, reaction settling pond, na2CO3 charge device, electrolysis system chlorine device, oxidation reactor, chlorine residue annihilator and bipolar membrane electrodialysis ware. The utility model discloses can be effectual in the recovery desulfurization waste water ca2+, mg2+ resource and produce acid -base solution retrieval and utilization simultaneously, reduce treatment cost.

Description

A kind of desulfurization wastewater that processes works in coordination with the system of Resource recovery

Technical field

This utility model belongs to coal-burning power plant's Industrial Wastewater Treatment and resource circulation utilization technical field, relates to a kind of desulfurization wastewater that processes and works in coordination with the system of Resource recovery.

Background technology

Under the strictest environmental protection policy, power plant's industrial water is all reused through step, and the most surplus last a small amount of tail end wastewater, to realize wastewater zero discharge, it is necessary to the desalination reuse and the subsequent cure that realize tail end wastewater process.Desulfurization wastewater is one of salinity and the highest tail end wastewater of pollutant levels in tail end wastewater, the most economical, effective process desulfurization wastewater and is just particularly important.Desulfurization wastewater contains the Ca of a large amount of high concentrations²⁺、Mg²⁺Deng cause incrustation ion, Cl^-And some heavy metal ion, additionally the ammonia nitrogen in power plant desulfurization waste water and organic concentration are the most of a relatively high.These features bring the biggest challenge to techniques such as the process of desulfurization wastewater, concentrations.

In traditional desulfuration waste water treatment process, the general method using direct chemical precipitation, such as single-stage chemical precipitation method, two-stage chemical precipitation method etc..Directly chemical precipitation method is most popular technique during current heat-engine plant desulfurized discharged wastewater met the national standard processes, desulfurization wastewater pH is mainly adjusted to about 9.5 by feeding lime breast by it, adds flocculating agent, flocculation aid realizes heavy metal precipitation and the last qualified discharge of the removal of float simultaneously.These method chemical feeding quantities are big, and generating a large amount of body refuse needs to process further, increases process investment cost, and substantial amounts of Cl in desulfurization wastewater^-Cannot be effectively addressed, production and the corrosion of processing system and potential pollution problem can be brought.Additionally ammonia nitrogen and the Organic substance of desulfurization wastewater middle and high concentration does not simply fail to use traditional handicraft to remove, and also some process technique of desulfurization wastewater can be brought threat, such as polluted membrane processing system etc..

Meanwhile, Mg (OH)₂As a kind of important industrial chemicals, especially as the fire retardant (Fireretardant) of a kind of function admirable, more and more paid close attention to by people.In recent years for the consideration of environmental protection and energy saving, the technical study reclaiming magnesium resource in the waste water of Mg rich content get more and more, such as: with sulfate hypotype salt lake bittern as raw material, use the technique of ammonia process magnesium sinking-ammonium hydrogen carbonate carbonization-calcining to prepare light magnesium oxide.Additionally calcium carbonate is widely used in multiple industry as a kind of important Inorganic Chemicals equally, and current Chinese scholars focuses mostly in the research of gas-liquid carbonizatin method, and this process is with Ca (OH)₂Aqueous emulsion, as calcium source, is passed through CO₂Calcium carbonate product is prepared in gas carbonization.But this method needs to consume substantial amounts of limestone and coal, in view of the finiteness of mineral resources and non-renewable, some new process routes constantly occur, such as the side-product CaCl with soda industry₂And NH₄HCO₃As primary raw material, solwution method is used to prepare calcium carbonate.

The same resources such as a large amount of magnesium, calcium that contain in desulfurization wastewater, and a large amount of Ca in tradition desulfurization wastewater processing procedure²⁺、Mg²⁺Get rid of with body refuse form Deng all, the most utterly useless also add body refuse amount and processing cost.

Utility model content

The purpose of this utility model is the shortcoming overcoming above-mentioned prior art, it is provided that a kind of desulfurization wastewater that processes works in coordination with the system of Resource recovery, and this system can effectively reclaim the Ca in desulfurization wastewater²⁺And Mg²⁺, and produce soda acid resource reusing in desulfurization wastewater treatment system.

For reaching above-mentioned purpose, the system that process desulfurization wastewater described in the utility model works in coordination with Resource recovery includes desulfurization wastewater input channel, pH regulator pond, reaction flotation tank, reaction settling basin, Na₂CO₃Chemicals dosing plant, preparing chlorine by electrolysis device, oxidation reactor, chlorine residue canceller and bipolar membrane electrodialysis device；

The alkali liquor outlet of bipolar membrane electrodialysis device is connected with the alkali liquor inlet of the alkali liquor inlet in pH regulator pond and reaction flotation tank, desulfurization wastewater input channel is connected with the entrance in pH regulator pond, the supernatant outlet in pH regulator pond is connected with the liquid inlet of reaction flotation tank, the bottom in pH regulator pond is provided with mud discharging mouth, the liquid outlet of reaction flotation tank is connected with the liquid inlet of reaction settling basin, Na₂CO₃The outlet of chemicals dosing plant is connected with the medicament entrance of reaction settling basin, the bottom of reaction settling basin is provided with precipitation outlet, the supernatant outlet of reaction settling basin is divided into two-way, wherein a road is connected with the entrance of preparing chlorine by electrolysis device, the outlet of another road and preparing chlorine by electrolysis device is all connected with the entrance of oxidation reactor, and the outlet of oxidation reactor is connected through the entrance of chlorine residue canceller with bipolar membrane electrodialysis device.

Also including that preliminary sedimentation tank, desulfurization wastewater input channel are connected with the entrance of preliminary sedimentation tank, the outlet of preliminary sedimentation tank is connected with the entrance in pH regulator pond.

The supernatant outlet in described pH regulator pond is connected by the liquid inlet of grade one filter with reaction flotation tank.

The outlet of oxidation reactor is connected with the entrance of bipolar membrane electrodialysis device through chlorine residue canceller and secondary filter successively.

The alkali liquor outlet of bipolar membrane electrodialysis device has alkali liquor storage pool, and the alkali liquor outlet of alkali liquor storage pool is connected with the alkali liquor inlet of the alkali liquor inlet in pH regulator pond and reaction flotation tank.

Also including acid solution storage pool and recovery system, the acid solution outlet of bipolar membrane electrodialysis device is connected with the entrance of acid solution storage pool, and the outlet of acid solution storage pool and the desalted water outlet of bipolar membrane electrodialysis device are all connected with recovery system.

This utility model has the advantages that

Process desulfurization wastewater described in the utility model works in coordination with the system of Resource recovery when operation, first passes through the pH value of pH regulator pond regulation desulfurization wastewater, then reclaims Mg (OH) by reaction flotation tank₂, the Ca in desulfurization wastewater is made the most again by reaction settling basin²⁺With CaCO₃Mode precipitate, thus realize Ca in desulfurization wastewater²⁺And Mg²⁺Recovery, simultaneously pH regulator pond and reaction flotation tank in use medicament be prepared from for raw material with desulfurization wastewater by bipolar membrane electrodialysis device, thus effectively reduce desulfurization wastewater process cost.Mg (OH) is reclaimed by reaction flotation tank₂Time, Mg (OH)₂Precipitation easily forms flco, it is achieved Mg (OH)₂Efficient recovery.It addition, this utility model carries out desalination by bipolar membrane electrodialysis device to desulfurization wastewater, produce acid and alkali liquor simultaneously, realize producing high-purity acid solution and alkali liquor while desalination, reclaim soda acid resource, reduce the medicament usage amount in desulfurization wastewater processing procedure, reduce processing cost.

Accompanying drawing explanation

Fig. 1 is schematic diagram of the present utility model.

Wherein, 1 be preliminary sedimentation tank, 2 be pH regulator pond, 3 be grade one filter, 4 be reaction flotation tank, 5 be reaction settling basin, 6 be preparing chlorine by electrolysis device, 7 be oxidation reactor, 8 be chlorine residue canceller, 9 be secondary filter, 10 be bipolar membrane electrodialysis device, 11 be acid solution storage pool, 12 for alkali liquor storage pool.

Detailed description of the invention

Below in conjunction with the accompanying drawings this utility model is described in further detail:

With reference to Fig. 1, the system that process desulfurization wastewater described in the utility model works in coordination with Resource recovery includes desulfurization wastewater input channel, pH regulator pond 2, reaction flotation tank 4, reaction settling basin 5, Na₂CO₃Chemicals dosing plant, preparing chlorine by electrolysis device 6, oxidation reactor 7, chlorine residue canceller 8 and bipolar membrane electrodialysis device 10；The alkali liquor outlet of bipolar membrane electrodialysis device 10 is connected with the alkali liquor inlet of the alkali liquor inlet in pH regulator pond 2 and reaction flotation tank 4, desulfurization wastewater input channel is connected with the entrance in pH regulator pond 2, the supernatant outlet in pH regulator pond 2 is connected with the liquid inlet of reaction flotation tank 4, the bottom in pH regulator pond 2 is provided with mud discharging mouth, the liquid outlet of reaction flotation tank 4 is connected with the liquid inlet of reaction settling basin 5, Na₂CO₃The outlet of chemicals dosing plant is connected with the medicament entrance of reaction settling basin 5, the bottom of reaction settling basin 5 is provided with precipitation outlet, the supernatant outlet of reaction settling basin 5 is divided into two-way, wherein a road is connected with the entrance of preparing chlorine by electrolysis device 6, the outlet of another road and preparing chlorine by electrolysis device 6 all entrances with oxidation reactor 7 are connected, and the entrance through chlorine residue canceller 8 with bipolar membrane electrodialysis device 10 that exports of oxidation reactor 7 is connected.

It should be noted that, this utility model also includes acid solution storage pool 11, recovery system and preliminary sedimentation tank 1, desulfurization wastewater input channel is connected with the entrance of preliminary sedimentation tank 1, the outlet of preliminary sedimentation tank 1 is connected with the entrance in pH regulator pond 2, the acid solution outlet of bipolar membrane electrodialysis device 10 is connected with the entrance of acid solution storage pool 11, and the outlet of acid solution storage pool 11 and the desalted water outlet of bipolar membrane electrodialysis device 10 are all connected with recovery system.

It addition, the supernatant outlet in described pH regulator pond 2 is connected by the liquid inlet of grade one filter 3 with reaction flotation tank 4；The outlet of oxidation reactor 7 is connected with the entrance of bipolar membrane electrodialysis device 10 through chlorine residue canceller 8 and secondary filter 9 successively；The alkali liquor outlet of bipolar membrane electrodialysis device 10 has alkali liquor storage pool 12, and the alkali liquor outlet of alkali liquor storage pool 12 is connected with the alkali liquor inlet of the alkali liquor inlet in pH regulator pond 2 and reaction flotation tank 4.

Specific operation process of the present utility model is:

The alkali liquor of bipolar membrane electrodialysis device 10 output has respectively entered in pH regulator pond 2 and reaction flotation tank 4, desulfurization wastewater is in desulfurization wastewater input channel enters pH regulator pond 2, and the pH value of described desulfurization wastewater is regulated by alkali liquor, mud bottom pH regulator pond 2 leads to mud discharging mouth discharges, supernatant in pH regulator pond 2 enters in reaction flotation tank 4, by the pH value of liquid in alkali liquor regulation reaction flotation tank 4, the liquid in reaction flotation tank 4 is made fully to react, the Mg (OH) that reaction generates₂Precipitation is reclaimed by air supporting recovery process, and reacted liquid enters in reaction settling basin 5, and and Na₂CO₃The Na of chemicals dosing plant output₂CO₃Hybrid reaction generates CaCO₃Precipitation, described CaCO₃Precipitate the sedimentation tank mouth bottom reacted sedimentation tank 5 to reclaim, during after reaction, in reaction settling basin 5, liquid has respectively entered preparing chlorine by electrolysis device 6 and oxidation reactor 7, and it is electrolytically generated containing effective oxychloride liquid in preparing chlorine by electrolysis device 6, in oxidation reactor 7, it is input to liquid mixing in oxidation reactor 7 with reaction settling basin 5 containing effective oxychloride liquid, remove the ammonia nitrogen in mixed solution and Organic substance, remove the mixed liquor after ammonia nitrogen and Organic substance and enter into bipolar membrane electrodialysis device 10 after chlorine residue canceller 8 gets rid of excess free chlorine and impurity, and while realizing desalination in the desalting chamber of bipolar membrane electrodialysis device 10, isolate acid solution and alkali liquor, complete the collaborative recovery of desulfurization wastewater.

Bipolar membrane electrodialysis device 10 needs before using first to sour room and the alkali indoor injection demineralized water of bipolar membrane electrodialysis device 10.

Embodiment one

The water quality of the desulfurization wastewater that power plant produces is as shown in table 1:

Table 1

The desulfurization wastewater 10m that heat-engine plant desulfurized tower is discharged³/ h, removes some precipitated impurities in desulfurization wastewater through preliminary sedimentation tank 1；Desulfurization wastewater supernatant after preformed precipitate enters in pH regulator pond 2, adds alkali liquor regulation desulfurization wastewater pH value to 10, aqueous slkali dosage (in terms of NaOH) as 1.8g/L, the Mg in desulfurization wastewater as pH=10 simultaneously²⁺Substantially without precipitation；Enter reaction gas after the precipitations such as the desulfurization wastewater in pH regulator pond 2 enters grade one filter 3 after pH regulator, the heavy metal generated in elimination water and other float and float pond 4；In reaction flotation tank 4, being firstly added alkali liquor regulation desulfurization wastewater pH value to 11, based on NaOH, dosage is about 8.4g/L, fully 1/2Mg in the supernatant of water after reaction²⁺Ion concentration is only 1.25mmol/L, Mg²⁺Substantially all generation Mg (OH)₂Flco, and Ca²⁺Content is basically unchanged；Through air supporting effect by Mg (OH)₂Flco comes together in scum trough and reclaims, Mg (OH)₂After recovery completes, measure 1/2Ca in water²⁺Ion concentration is 90mmol/L, adds the Na of 4.8g/L₂CO₃Generate CaCO₃Precipitation, reclaims CaCO through reaction settling basin 5 precipitation₃Body refuse, Ca in desulfurization wastewater after reaction²⁺Concentration is down to 0.125mmol/L；Remove Ca²⁺And Mg²⁺After desulfurization wastewater be divided into two-way: wherein a road enters preparing chlorine by electrolysis device 6, utilizes the Cl of desulfurization wastewater middle and high concentration^-Producing the oxidation solution of effective chlorine 2g/L, converge with another road desulfurization wastewater in oxidation reaction pond subsequently, after haptoreaction 30min, ammonia nitrogen concentration is 10mg/L, and organic concentration is 11.4mg/L；After oxidation reactor 7 is by Organic substance and ammonia nitrogen removal, enter in bipolar membrane electrodialysis device 10 after fine suspension in chlorine residue canceller 8 and secondary filter 9 eliminate remaining effective chlorine and water again, and in bipolar membrane electrodialysis device 10 desalting processing, acid solution and concentration of lye that bipolar membrane electrodialysis device 10 is discharged control at 1mol/L, and be separately stored in acid solution storage pool 11 and alkali liquor storage pool 12, wherein aqueous slkali is back to pH regulator pond 2 and reaction flotation tank 4, and acid solution then enters in recovery system.

Implementation result: use PROCESS FOR TREATMENT desulfurization wastewater of the present utility model, through Ca²⁺、Mg²⁺After recycling, Mg in water²⁺For 1.25mmol/L, Ca²⁺For 0.125mmol/L；Reclaim Mg (OH)₂And CaCO₃Purity, all 90%, is added medicament and is only a small amount of Na₂CO₃, after process, in desulfurization wastewater, ammonia nitrogen is that 10mg/L, TOC drop to the follow-up process of dropping to of 11.4mg/L, Organic substance and ammonia nitrogen and provide condition, and the acid solution obtained and the concentration of alkali liquor are the acid-base solution of 1mol/L.

Claims (6)

1. one kind processes desulfurization wastewater and works in coordination with the system of Resource recovery, it is characterised in that include desulfurization wastewater input channel, pH regulator pond (2), reaction flotation tank (4), reaction settling basin (5), Na₂CO₃Chemicals dosing plant, preparing chlorine by electrolysis device (6), oxidation reactor (7), chlorine residue canceller (8) and bipolar membrane electrodialysis device (10)；

The alkali liquor outlet of bipolar membrane electrodialysis device (10) is connected with the alkali liquor inlet of pH regulator pond (2) and the alkali liquor inlet of reaction flotation tank (4), desulfurization wastewater input channel is connected with the entrance of pH regulator pond (2), the supernatant outlet in pH regulator pond (2) is connected with the liquid inlet of reaction flotation tank (4), the bottom in pH regulator pond (2) is provided with mud discharging mouth, the liquid outlet of reaction flotation tank (4) is connected with the liquid inlet of reaction settling basin (5), Na₂CO₃The outlet of chemicals dosing plant is connected with the medicament entrance of reaction settling basin (5), the bottom of reaction settling basin (5) is provided with precipitation outlet, the supernatant outlet of reaction settling basin (5) is divided into two-way, wherein, one tunnel is connected with the entrance of preparing chlorine by electrolysis device (6), the outlet of another road and preparing chlorine by electrolysis device (6) all entrances with oxidation reactor (7) are connected, and the outlet of oxidation reactor (7) is connected through the entrance of chlorine residue canceller (8) with bipolar membrane electrodialysis device (10).

Process desulfurization wastewater the most according to claim 1 works in coordination with the system of Resource recovery, it is characterized in that, also include preliminary sedimentation tank (1), desulfurization wastewater input channel is connected with the entrance of preliminary sedimentation tank (1), and the outlet of preliminary sedimentation tank (1) is connected with the entrance of pH regulator pond (2).

Process desulfurization wastewater the most according to claim 1 works in coordination with the system of Resource recovery, it is characterized in that, the supernatant outlet of described pH regulator pond (2) is connected by the liquid inlet of grade one filter (3) with reaction flotation tank (4).

Process desulfurization wastewater the most according to claim 3 works in coordination with the system of Resource recovery, it is characterized in that, the outlet of oxidation reactor (7) is connected with the entrance of bipolar membrane electrodialysis device (10) through chlorine residue canceller (8) and secondary filter (9) successively.

Process desulfurization wastewater the most according to claim 1 works in coordination with the system of Resource recovery, it is characterized in that, the alkali liquor outlet of bipolar membrane electrodialysis device (10) has alkali liquor storage pool (12), and the alkali liquor outlet of alkali liquor storage pool (12) is connected with the alkali liquor inlet of pH regulator pond (2) and the alkali liquor inlet of reaction flotation tank (4).

Process desulfurization wastewater the most according to claim 1 works in coordination with the system of Resource recovery, it is characterized in that, also include acid solution storage pool (11) and recovery system, the acid solution outlet of bipolar membrane electrodialysis device (10) is connected with the entrance of acid solution storage pool (11), and the outlet of acid solution storage pool (11) and the desalted water outlet of bipolar membrane electrodialysis device (10) are all connected with recovery system.