CN110745989B

CN110745989B - Activated carbon flue gas purification acid-making wastewater zero-discharge process and system

Info

Publication number: CN110745989B
Application number: CN201911020674.7A
Authority: CN
Inventors: 刘义; 陈红; 黄伏根
Original assignee: Hunan Zhongye Changtian Energy Conservation And Environmental Protection Technology Co ltd
Current assignee: Hunan Zhongye Changtian Energy Conservation And Environmental Protection Technology Co ltd
Priority date: 2019-10-25
Filing date: 2019-10-25
Publication date: 2022-02-18
Anticipated expiration: 2039-10-25
Also published as: CN110745989A

Abstract

The activated carbon flue gas purification acid making wastewater zero discharge process and system are characterized in that acid making complex sewage is treated through the steps 1) to 4) in sequence, and the treated sewage is used as a substitute of industrial new water and is used for sintering mixed materials or slag flushing in a steel mill. The gas generated in the step 1) and the step 2) can be recycled for the second time. Under the action of the acid dehydration device, the sludge produced by the acid precipitation device is recycled, and the produced acid filtrate is recycled through a fifth pipeline. The deacidified sludge produced is recovered through a sixth pipeline. The scheme that this application provided can be directed against quality of water characteristics, and rational utilization technology improves treatment effeciency and operating stability, and it is low to reduce investment and running cost, reduces the operation maintenance degree of difficulty, reduces the pollution to the air simultaneously, can be reasonable distribute the utilization, retrieves waste gas waste material in the technology simultaneously and eliminates, is favorable to reduction in production cost, satisfies the environmental protection standard.

Description

Activated carbon flue gas purification acid-making wastewater zero-discharge process and system

Technical Field

The invention relates to a sewage treatment process, in particular to an activated carbon flue gas purification acid-making wastewater zero-discharge process, and belongs to the technical field of sewage treatment. The invention also relates to a zero discharge system for the waste water generated in the acid production by activated carbon flue gas purification

Background

With the increasing national requirements on the emission indexes of sintering flue gas of steel plants, more and more steel plants adopt an activated carbon method to purify the sintering flue gas at present, the process mainly adopts activated carbon and adds ammonia gas to adsorb and remove harmful substances such as sulfur dioxide, nitrogen oxides, dioxin and the like in the flue gas, the adsorbed activated carbon can generate high-concentration sulfur dioxide analytic gas through high-temperature analytic regeneration, and the sulfur dioxide analytic gas is commonly used for preparing concentrated sulfuric acid in order to realize the recycling of sulfur dioxide. In order to ensure the quality of sulfuric acid and the stability of an acid making system, a washing method is often adopted to wash and remove impurities from the analytic gas, so that a large amount of acid flue gas washing sewage, namely acid making sewage, is generated.

Since the analysis gas often contains a large amount of sulfur dioxide and a small amount of sulfur trioxide, the analysis gas can be dissolved into water in the washing process, so that the washing sewage is generally acidic. And the washing sewage components are easily affected by sintering flue gas components, an adsorbent and an analysis process, so that the types of the washing sewage components are various, and impurities in the analysis gas are complex and high in concentration, so that the acid-making washing sewage components are particularly complex.

Through long-term tracking research, the acid making sewage is determined to be complex acidic sewage with high suspended matter content, high COD (chemical oxygen demand), high ammonia nitrogen content, high heavy metal content, high chlorine content and high salt content. The pH value of the complex acidic sewage is 1-2, the content of suspended matters is 1000-5000 mg/L, the content of COD is 1000-5000 mg/L, the content of ammonia nitrogen is 10000-20000 mg/L, the content of ferrous ions is more than 200mg/L, the total concentration of calcium and magnesium is 100-400 mg/L, the content of chloride ions is 20000-50000 mg/L, and the concentration of salt is 100-300 g/L. At present, the sewage treatment process only stays in a research stage, a mature technology which can be used for reference is not available at home and abroad, and a case and experience for stable operation are not available in engineering.

At present, the sintering flue gas active carbon desulfurization acid-making sewage is an important link influencing the popularization of the active carbon flue gas purification technology, but because the water quality and the components of the sewage are complex, the existing sewage treatment process does not have a treatment process which is effective and stable in operation for the sewage. Many activated carbon flue gas purification projects which are put into operation have the problems that the acid-making sewage is difficult to treat and the treatment process is unstable. For example, when Taigang stainless steel is introduced to the flue gas desulfurization project of sintered activated carbon in the technical construction of Japan in 2006, Japanese shows that the acid production wastewater is complex in quality and difficult to treat. In the newly-built activated carbon flue gas desulfurization projects in various places in recent years, acid-making wastewater treatment systems do not operate well. The treatment of the wastewater generated in the acid preparation by the activated carbon becomes a worldwide problem. There is therefore a critical need to find better solutions.

How to provide an active carbon flue gas purification system acid waste water zero discharge system, it can be administered the complicated acid sewage of high suspended solid, high COD, high ammonia nitrogen, high heavy metal content, high salt content, can rational utilization and the waste gas waste material that produces among the recovery processing process, reduce the emission of waste gas waste material, improved the throughput of this processing system to the complicated sewage of system acid, practiced thrift the manufacturing cost of enterprise, the technical problem that technical staff in the field awaits a great deal of solution.

Disclosure of Invention

Aiming at the defects of the prior art, the treatment system can treat the complex acidic sewage with high suspended matters, high COD, high ammonia nitrogen, high heavy metal content and high salt content, can reasonably utilize and recycle the waste gas and waste materials generated in the treatment process, reduces the discharge of the waste gas and waste materials, improves the treatment capacity of the treatment system on the complex sewage for acid production, and saves the production cost of enterprises. The invention provides an activated carbon flue gas purification acid-making wastewater zero-discharge process, which comprises the following steps: 1) and precipitating the acid-making complex sewage in an acid precipitation device, and feeding the acid generated in the precipitation process into an acid gas recovery device for recovery through an acid gas return pipeline. 2) And (2) sequentially introducing the acid-making complex sewage precipitated by the acid precipitation device into a first neutralization tank, a first oxidation tank and a flocculation precipitation tank of the metal ion precipitation device for metal ion precipitation, and introducing ammonia gas generated in the first neutralization tank, the first oxidation tank and the flocculation precipitation tank into an ammonia gas recovery device for recovery. 3) And (3) introducing the acid-making complex sewage precipitated by the flocculation sedimentation tank into an ammonia removal device through a tenth pipeline for ammonia removal, and removing ammonia from the acid-making complex sewage in the ammonia removal device through an ultrafilter, a cartridge filter and an ammonia absorber in sequence. 4) And (3) introducing the acid-making complex sewage subjected to ammonia removal by the ammonia absorber into a second oxidation tank of the deep oxidation device for oxidation, and then introducing the oxidized sewage into a second neutralization tank for neutralization reaction to generate industrial water for later use. The industrial water is used for sintering mixed materials or slag flushing in steel works. In the step 1), acid bottom sludge generated in the acid precipitation device is introduced into a bottom sludge deacidification dehydration device, acid filtrate generated in the bottom sludge deacidification dehydration device is recycled through a fifth pipeline, and deacidified sludge generated in the bottom sludge deacidification dehydration device is recycled through a sixth pipeline.

According to the first embodiment of the invention, the zero discharge process of the acid making wastewater by activated carbon flue gas purification is provided:

a zero discharge process for activated carbon flue gas purification acid making wastewater comprises the following steps:

1) and precipitating the acid-making complex sewage in an acid precipitation device, and feeding the acid generated in the precipitation process into an acid gas recovery device for recovery through an acid gas return pipeline.

2) And (2) sequentially introducing the acid-making complex sewage precipitated by the acid precipitation device into a first neutralization tank, a first oxidation tank and a flocculation precipitation tank of the metal ion precipitation device for metal ion precipitation, and introducing ammonia gas generated in the first neutralization tank, the first oxidation tank and the flocculation precipitation tank into an ammonia gas recovery device for recovery.

3) And (3) introducing the acid-making complex sewage precipitated by the flocculation sedimentation tank into an ammonia removal device through a tenth pipeline for ammonia removal, and removing ammonia from the acid-making complex sewage in the ammonia removal device through an ultrafilter, a cartridge filter and an ammonia absorber in sequence.

4) And (3) introducing the acid-making complex sewage subjected to ammonia removal by the ammonia absorber into a second oxidation tank of the deep oxidation device for oxidation, and then introducing the oxidized sewage into a second neutralization tank for neutralization reaction to generate industrial water for later use. The industrial water is used for sintering mixed materials or slag flushing in steel works.

In the step 1), acid bottom sludge generated in the acid precipitation device is introduced into a bottom sludge deacidification dehydration device, acid filtrate generated in the bottom sludge deacidification dehydration device is recycled through a fifth pipeline, and deacidified sludge (rich in activated carbon powder and capable of being used as sintering fuel) generated in the bottom sludge deacidification dehydration device is recycled through a sixth pipeline.

Preferably, in the step 2), the alkaline bottom sludge generated in the flocculation sedimentation tank is introduced into a bottom sludge dealkalization dehydration device, alkaline filtrate generated in the bottom sludge dealkalization dehydration device is recovered through a seventh pipeline, and dealkalized sludge (rich in iron and capable of being used as sintered iron ore raw material for recovering iron resources) generated in the bottom sludge dealkalization dehydration device is recovered through an eighth pipeline.

Preferably, in the step 3), lye is added into the tenth pipeline through a lye supplementing device.

Preferably, in the step 3), the acid production complex sewage is firstly introduced into an ammonia removal device in the ammonia removal device to remove ammonia by blowing, and then ammonia is removed through an ultrafilter, a cartridge filter and an ammonia absorber in sequence.

Preferably, the absorption liquid generated in the ammonia absorber is introduced into a stripping device to strip ammonia.

Preferably, the ammonia gas discharged from the stripping device is introduced into the activated carbon adsorption tower through an eleventh pipeline to adsorb nitrogen oxides.

Preferably, in the step 1), the acid-making complex sewage is firstly introduced into a water quality adjusting device for water quality adjustment, and then is introduced into an acid precipitation device for precipitation. The supernatant is used as circulating spray water of a purification device of an acid making system to replace industrial fresh water so as to save water resources, and the precipitated bottom mud is dehydrated and then reused in sintering raw materials, so that solid waste is not generated, the supernatant is also used as sintering fuel, and the normal operation of a sintering system is not influenced.

Preferably, in the step 1), the acid gas generated by the water quality adjusting device is introduced into the acid in the acid gas return pipeline through the twelfth pipeline to recover the sulfur resource.

Preferably, in the step 1), the acid gas collected in the acid gas recovery device is introduced into a spray tower of an acid making system through a first pipeline to be sprayed and adsorbed to make acid.

Preferably, in the step 1), the supernatant produced in the acidic precipitation device is introduced into the spray tower of the acid making system through a ninth pipeline to adsorb the acid gas.

Preferably, in step 1), the fifth pipeline is led into a water quality adjusting device for recycling, and the acid filtrate generated in the bottom sediment deacidification and dehydration device is adjusted by the water quality adjusting device.

Preferably, the sixth pipeline is led into a sintering batching device for recycling, and the produced deacidified sludge is used for sintering batching.

Preferably, in the step 2), the seventh pipeline is led into a first neutralization tank for recycling, and the alkaline filtrate generated in the bottom sediment alkaline dewatering device is neutralized through the first neutralization tank.

Preferably, the eighth pipeline is led into a sintering batching device for recycling, and the generated dealkalized sludge is used for sintering batching to recycle iron resources.

Preferably, in the step 2), the ammonia gas recovered by the ammonia gas recovery device is introduced into the activated carbon adsorption tower through the second pipeline to adsorb nitrogen oxides.

In the first embodiment, the acid-making complex sewage is treated sequentially through the steps 1) to 4) and is used as a substitute of industrial fresh water for sintering mixed materials or slag flushing in steel works after being treated. And (3) standing the acid-making complex sewage in the step 1) in an acid precipitation device, and carrying sulfur precipitation with activated carbon. In the step 2), the sewage enters a metal element precipitation device, and in the metal element precipitation device, the metal elements of the sewage react, precipitate and are separated from the sewage. In the step 3), the sewage enters an ammonia removal device, and ammonium ions in the sewage react to become ammonia gas to be discharged. In the step 4), the sewage enters the deep oxidation device, and high COD in the sewage is oxidized and decomposed. In the step 1), gas generated in the precipitation process enters an acid gas recovery device through an acid gas return pipeline for recovery. And in the step 2), ammonia gas generated by the metal ion precipitation device enters an ammonia gas recovery device for recovery. Under the action of the acid gas recovery device and the ammonia gas recovery device, the gas generated in the step 1) and the step 2) can be recycled for the second time. Under the action of the acid dehydration device, the sludge produced by the acid precipitation device is recycled, and the produced acid filtrate is recycled through a fifth pipeline. The deacidified sludge produced is recovered through a sixth pipeline. And meanwhile, the air pollution is reduced, the air can be reasonably distributed and utilized, and meanwhile, waste gas and waste materials are recycled and eliminated in the process. Is beneficial to reducing the production cost and meets the environmental protection standard.

In the first embodiment, under the action of the alkaline dewatering device, the sludge produced by the flocculation sedimentation tank is subjected to recovery treatment, alkaline filtrate produced in the process is recovered through the seventh pipeline, and the produced dealkalized sludge is recovered through the eighth pipeline. That is to say, the precipitated sludge generated in the flocculation sedimentation tank of the metal ion precipitation device is effectively recycled and treated.

In the first embodiment, lye is added to the tenth pipe through lye supplementing means. The ammonium ions are more easily separated from the sewage in the form of ammonia gas by combining the hydroxide ions with the ammonium ions. Is beneficial to the ammonia stripping at the rear section.

In the first embodiment, the complex sewage generated in acid production is firstly introduced into the blowing-off device in the ammonia removal device to blow off ammonia, and the blowing-off device is used for blowing off the sewage with high efficiency, so that a large amount of ammonium ions in the sewage can be removed under the condition of low energy consumption.

The formula:

from the above formula, it can be known that when the ammonia gas is blown away, the equilibrium direction of the above formula is shifted to the right, i.e. the ammonium ions will continue to react with the hydroxide ions to combine into ammonia gas.

In the first embodiment, the ammonia gas discharged from the stripping device is introduced into the activated carbon adsorption tower to adsorb nitrogen oxide, which is beneficial to saving the use of extra ammonia gas in the activated carbon adsorption tower.

In the first embodiment, in the step 1), before entering the acid precipitation device, the sewage enters the water quality adjusting device for water quality adjustment, which is beneficial to the treatment of the sewage in the following steps.

In the first embodiment, in step 1), the acid gas collected in the acid gas recovery device is introduced into the spray tower of the acid making system through the first pipeline to be sprayed and adsorbed to make acid, and on the premise of effectively preventing sulfide leakage, the sulfur oxide is introduced back to the spray tower of the acid making system to perform the acid making process again, so that the loss of sulfur element can be prevented.

In a first embodiment, the supernatant produced in the acid precipitation unit is passed through a ninth conduit to an acid system spray tower to adsorb acid gases. The supernatant can be used as an adsorption liquid for adsorbing the acid gas, thereby reducing the waste of water resources. The supernatant is used as circulating spray water of a purification device of an acid making system to replace industrial fresh water so as to save water resources, and the precipitated bottom mud is dehydrated and then reused in sintering raw materials, so that solid waste is not generated, the supernatant is also used as sintering fuel, and the normal operation of a sintering system is not influenced.

In the first embodiment, the acidic filtrate generated in the acidic dehydration device is introduced into the water quality adjusting device through the fifth pipeline, and is adjusted in the water quality adjustment to reduce the discharge of acidic liquid.

In the first embodiment, the deacidified sludge and the dealkalized sludge produced in the acidic dehydration unit and the alkaline dehydration unit enter the sintering and batching unit through the sixth pipeline and the eighth pipeline for sintering and batching.

According to a second embodiment of the invention, a zero discharge system for acid making wastewater by activated carbon flue gas purification is provided:

the second implementation scheme provided by the invention has the characteristics of great engineering significance, strong pertinence of water quality, high treatment efficiency, stable operation, low investment and operation cost, convenience in operation and maintenance and the like. The invention has the beneficial effects that: fully aiming at the characteristics of water quality, advanced and reasonable process technology and great engineering application value, opens up a treatment process with practical significance for the treatment of the sewage generated in the acid production by the desulfurization of the sintering flue gas activated carbon, and provides technical support for the popularization of the sintering flue gas activated carbon purification technology.

The utility model provides an active carbon gas cleaning system acid waste water zero discharge system, this system includes: acid precipitation device, metal ion precipitation device, ammonia removal device, deep oxidation device, acid gas recovery device, ammonia recovery device. And the acid-making complex sewage is treated by the acid precipitation device, the metal ion precipitation device, the ammonia removal device and the deep oxidation device in sequence and then recycled or discharged. The acid-making complex sewage is communicated with the acid precipitation device through an original sewage pipeline. And an acid gas return pipeline of the acid gas recovery device is communicated with an exhaust port of the acid precipitation device. The exhaust outlet of the acid gas recovery device is communicated with the first pipeline. And an ammonia return air pipeline of the ammonia recovery device is communicated with an exhaust port of the metal ion precipitation device. And an air outlet of the ammonia gas recovery device is communicated with the second pipeline.

Preferably, the metal ion precipitation device includes: the first neutralization pond, the first oxidation pond, flocculation and precipitation pond. And the liquid inlet of the first neutralization pond is communicated with the liquid outlet of the acid precipitation device. The sewage passing through the acidic precipitation device sequentially passes through a first neutralization tank, a first oxidation tank and a flocculation precipitation tank in the metal ion precipitation device. The first oxidation pond is provided with an oxide inlet. The first oxidation pond is provided with a precipitator inlet.

Preferably, the communication between the ammonia return air pipeline of the ammonia recovery device and the exhaust port of the metal ion precipitation device is as follows: and an ammonia return air pipeline of the ammonia recovery device is communicated with an exhaust port of the first neutralization tank.

Preferably, the exhaust port of the first oxidation pond is connected with ammonia in the ammonia return pipeline through a third pipeline and/or the exhaust port of the flocculation sedimentation pond is connected with ammonia in the ammonia return pipeline through a fourth pipeline.

Preferably, the system further comprises: a bottom sludge deacidification dehydration device. An acid sludge pumping pipe of the bottom sludge deacidification dehydration device is communicated with a sludge discharge port of the acid precipitation device. And an acid filtrate discharge port of the bottom sludge deacidification and dehydration device is communicated with a fifth pipeline. And a deacidification sludge discharge port of the bottom sludge deacidification dehydration device is communicated with a sixth pipeline.

Preferably, the system further comprises: a bottom mud alkali-removing dehydration device. The alkaline sludge pumping pipe of the bottom sludge alkaline-removing dehydration device is communicated with a sludge discharge port of the flocculation sedimentation tank. And an alkaline filtrate discharge port of the bottom mud alkaline-removing dehydration device is communicated with a seventh pipeline. And a dealkalized sludge discharge port of the bottom sludge dealkalized dehydration device is communicated with an eighth pipeline.

Preferably, a clear liquid precipitation outlet of the acid precipitation device is communicated to a spraying liquid supplement inlet of a spraying tower of the acid making system through a ninth pipeline. The supernatant is used as circulating spray water of a purification device of an acid making system to replace industrial fresh water so as to save water resources, and the precipitated bottom mud is dehydrated and then reused in sintering raw materials, so that solid waste is not generated, the supernatant is also used as sintering fuel, and the normal operation of a sintering system is not influenced.

Preferably, the first pipeline is communicated to an inlet of a flue gas pipeline to be adsorbed of a spray tower of the acid making system.

Preferably, the second pipeline is communicated to a flue gas inlet of the activated carbon adsorption tower.

Preferably, the liquid outlet of the flocculation sedimentation tank is communicated with the liquid inlet of the ammonia removal device through a tenth pipeline. The ammonia removal device comprises an ultrafilter, a cartridge filter and an ammonia absorber. The sewage passing through the metal ion precipitation device is treated by an ultrafilter, a cartridge filter and an ammonia absorber in turn in an ammonia removal device and then enters a deep oxidation device.

Preferably, the ammonia absorber comprises: deamination reaction cavity, deamination membrane, dilute acid inlet and absorption liquid outlet. The deamination membrane is arranged in the deamination reaction cavity. The absorption liquid inlet is arranged on the deamination reaction cavity at one side of the deamination membrane. The absorption liquid outlet is arranged on the deamination reaction cavity at the other side of the deamination membrane. Sewage passes through the cavity on one side of the absorption liquid inlet in the deamination reaction cavity and then enters the deep oxidation device.

Preferably, the ammonia removal device further comprises: an alkali liquor replenishing device. And a liquid outlet of the alkali liquor supplementing device is communicated to a tenth pipeline.

Preferably, a second pH value detection sensor is arranged on the tenth pipeline and is positioned at the downstream of the lye supplementing device.

Preferably, the ammonia removal device further comprises: and a stripping device. The blow-off device is arranged at the upstream of the ultrafilter. The liquid outlet of the flocculation sedimentation tank is communicated to the liquid inlet of the stripping device through a tenth pipeline. An ammonia gas outlet on the stripping device is communicated with the eleventh pipeline.

Preferably, the absorption liquid discharge port is communicated to the blow-off device.

Preferably, the eleventh pipeline is communicated to a flue gas inlet of the activated carbon adsorption tower.

Preferably, the system also comprises a water quality adjusting device, the water quality adjusting device is arranged on the original sewage pipeline, and the acid-making complex sewage is treated by the water quality adjusting device and then enters the acid precipitation device.

Preferably, the exhaust outlet of the water quality adjusting device is connected with the acid of the acid gas return pipeline through a twelfth pipeline.

Preferably, the acid liquor replenishing port of the water quality adjusting device is communicated with the fifth pipeline.

Preferably, the water quality adjusting device is provided with a water replenishing port. A first stirring mechanism is arranged in the water quality adjusting device.

Preferably, the acid sedimentation tank is provided with a suspended matter removing mechanism.

Preferably, the first neutralization tank is provided with an alkali liquor inlet and a first pH value detection sensor.

Preferably, a second stirring mechanism is arranged in the flocculation sedimentation tank.

Preferably, the first stirring mechanism and the second stirring mechanism are air stirring devices or mechanical stirring devices. The oxide inlet on the first oxidation pond is communicated with air. The precipitator inlet on the first oxidation pond is communicated with a carbonate storage device. The second oxidation tank is a catalytic oxidation device.

Preferably, the deep oxidation apparatus includes: a second oxidation pond and a second neutralization pond. And the sewage is treated in the advanced oxidation device sequentially through the second oxidation tank and the second neutralization tank and then is discharged outwards.

Preferably, the second neutralization tank is provided with a third pH detection sensor.

In a second embodiment, the wastewater can be effectively treated by the system. The sewage is kept stand in an acid precipitation device, and the activated carbon carries with sulfur for precipitation. And then the sewage enters a metal element precipitation device, and in the metal element precipitation device, the metal elements of the sewage react, precipitate and are separated from the sewage. Then the sewage enters an ammonia removal device, and ammonium ions in the sewage react to become ammonia gas to be discharged. And finally, the sewage enters the deep oxidation device, and high COD in the sewage is subjected to oxidative decomposition. Wherein, the sewage is the sewage containing a large amount of acidic pollutants and is in the metal elementIn the first neutralization pond of the element precipitation device, firstly adding alkali to adjust the pH value of the sewage to make the sewage alkaline, namely, a large amount of OH exists in the solution^-(hydroxide ion) to thereby form Fe (OH) in the wastewater₂(ferrous hydroxide) precipitation, and other metal hydroxide precipitation. The addition of a base also allows the ammonium ions in solution to react with the hydroxide ions under alkaline conditions to produce gaseous molecular ammonia. Then the sewage enters a first oxidation tank, in which reducing substances in the sewage react with additionally input oxides to obtain Fe²⁺(ferrous ion) Oxidation to Fe³⁺(ferric ion). Fe³⁺(ferric ions) with a large amount of OH generated in the first neutralization tank^-(hydroxide ion) binding to form Fe (OH)₃(iron hydroxide) precipitation. In the first oxidation pond, a precipitator is also added to precipitate calcium and magnesium metal elements in the sewage. Among the technical scheme of this application, get rid of the COD and need the extremely strong oxide of oxidability, because the reductibility of ammonium ion is stronger than COD, if under the condition of not getting rid of ammonia, directly carry out the oxidation to sewage and remove COD, will consume a large amount of oxides, improve sewage treatment's cost, and this scheme progressively gets rid of sulphur simple substance and metallic element in the sewage earlier, gets rid of ammonia again, adopts strong oxidizer to get rid of COD at last. The steps are simple, the thought is clear, and the control is convenient. Greatly reduces the cost of sewage treatment.

It should be noted that the chemical reaction equation of the precipitate generated by the combination of the metal ions, ammonium ions and hydroxyl ions in the wastewater is:

OH-+Fe²⁺＝Fe(OH)₂↓；

nOH^-+Mn⁺＝M(OH)n↓；

wherein M represents other metal ions in the sewage, and the function of adding alkali is to react with the metal ions in the sewage to generate precipitates.

In a second embodiment, there are specific examples of the first oxygenThe oxide added in the chemical pool is specifically air, namely air is introduced into the first oxidation pool, and the oxygen in the air is used for oxidizing Fe²⁺(ferrous ion). The precipitator put into the first oxidation pond is soluble salt containing carbonate. Soluble salts containing carbonate groups produce CO upon dissolution in water₃ ^2-(carbonate ion), CO₃ ^2-(carbonate ion) reacts with calcium and magnesium metal ions to generate precipitate.

The chemical equation for the reaction is:

4Fe(OH)₂+O₂+2H₂O＝4Fe(OH)₃；

CO₃ ^2-+Ca²⁺＝CaCO3↓；

CO₃ ^2-+Mg²⁺＝MgCO3↓；

in a second embodiment, the sewage enters a flocculation sedimentation tank, the sewage is uniformly reflected in the flocculation sedimentation tank through a second stirrer in the flocculation sedimentation tank, and after the sewage is fully mixed, the sewage is precipitated to remove sediments containing metal elements in the sewage.

In a second embodiment, the wastewater from which the sediment is removed in the flocculation sedimentation tank is passed to an apparatus for ammonia removal. In the ammonia removal device, particulate matters in sewage are removed through an ultra-filter and a cartridge filter, particularly the ultra-filter removes the particulate matters in the sewage, and the cartridge filter is used for preventing the particulate matters which are not filtered by the ultra-filter from entering an ammonia absorber. After the sewage absorbs ammonia through the ammonia absorber, the sewage only rich in COD reducing substances is discharged.

It is noted that the ultrafilter removes suspended matters in sewage to provide conditions for entering the deamination membrane, and the cartridge filter is used for preventing the deamination membrane from being blocked when the water produced by ultrafiltration is not good. The ammonia absorber further removes ammonia nitrogen in the sewage

In a second embodiment, an ammonia absorber comprises: deamination reaction cavity, deamination membrane, absorption liquid inlet and absorption liquid outlet. The deammoniation reaction cavity is divided into a dilute acid mixing cavity and an absorption cavity by the deammoniation membrane, an absorption liquid inlet is arranged in the dilute acid mixing cavity, and an absorption liquid outlet is arranged in the absorption cavity. The sewage entering the ammonia absorber also contains part of ammonia which is not separated. Diluted acid is added into the sewage to change ammonia in the sewage into ammonium ions which easily pass through the deamination membrane and are discharged from an absorption liquid outlet in the absorption cavity.

In a second embodiment, the first pipeline is provided with an alkali liquor supplementing device, so that the alkalinity of the sewage entering the ammonia removal device can be improved. The ammonia is discharged from the sewage in a gas form.

In a second embodiment, a second pH value detection sensor is arranged below the alkali liquor supplementing device, and the pH value of the sewage after the alkali liquor is supplemented is monitored in real time.

In a second embodiment, the ammonia removal unit further comprises a stripping unit, which is arranged upstream of the ultrafilter. The blowing-off device adopts a gas blowing deamination mode to separate ammonia molecules from sewage.

The alkali liquor replenishing device is used for increasing the pH value of the sewage to 10-13. The purpose is to make

The equilibrium reaction is moved to the right, so that ammonium ions in the wastewater are all converted into gaseous free ammonia, and then the ammonia is removed by a high-efficiency stripping process. The principle of efficient ammonia stripping is that air is blown into waste water to generate a large amount of bubbles, so that the bubbles and the waste water are fully contacted with each other, and ammonia molecules dissolved in water pass through a gas-liquid interface and are transferred to a gas phase to achieve the aim of removing ammonia.

In the second embodiment, as a specific example, the solution discharged from the discharge port of the absorbing liquid contains a part of ammonium ions, and the ammonium ions are introduced into the waste water containing a large amount of hydroxide ions, so that the ammonium ions react with the hydroxide ions to generate ammonia. And then removed by the stripping device.

In the second embodiment, the first neutralization tank is provided with a first pH detection sensor which can accurately know the pH value of the sewage after the alkali is added. Is beneficial to controlling the adding amount of the alkali.

In a second embodiment, a wastewater treatment plant for first-order treatment of a system, comprising: the water quality adjusting device adjusts the water content of the sewage and improves the uniformity of the sewage quality, and provides a proper water quality condition for the subsequent treatment. Regulating the water quantity of the sewage and the uniformity of the water quality. Is favorable for the treatment of sewage in the later period. Because the sewage is provided with some suspended impurities, the suspended impurities above the sewage are removed by the suspended matter removing mechanism.

In the second embodiment, COD is removed by oxidizing macromolecular refractory organics into low-toxic or non-toxic small molecular substances by COD reductants in the sewage at the end of the deep oxidation device.

The ammonia removal device removes ammonia from the sewage and enters the deep oxidation device to remove COD after the ammonia reaches the standard.

The advanced oxidation method adopted in the deep oxidation device is based on the principle that hydroxyl free radicals (OH) with strong oxidation capacity are generated (the oxidation reduction potential is +2.8V, the higher the oxidation reduction potential is, the stronger the oxidation capacity is), and under the reaction conditions of high temperature and high pressure, electricity, sound, light irradiation, catalysts and the like, macromolecular refractory organic matters are oxidized into low-toxicity or non-toxic micromolecular substances, so that COD is removed. And discharging the effluent of the deep oxidation device into a final second neutralization pond, adjusting the pH value to 6-9, and then recycling or discharging.

It is further described that COD is the amount of the reduced matter to be oxidized.

All the tanks can be grooves in the application, and the material of the tanks (grooves) can adopt glass fiber reinforced plastics, steel lining glue, steel lining glass fiber reinforced plastics or concrete lining anti-corrosion coatings and the like.

The mixer in this application can adopt air stirring and mechanical stirring, and steel lining glue or steel lining glass steel can be chooseed for use to mechanical stirring equipment material.

The flocculation sedimentation tank (tank) can be independently arranged by two tanks (tanks); or can be combined into a pool (groove) which is divided into two grids. However, stirring equipment is required to be arranged in the flocculation tank (trough): mechanical stirring or air stirring can be adopted.

The ultrafilter described in this application can be an internal ultrafiltration or an external ultrafiltration, and the internal ultrafiltration is preferably adopted because the ultrafilter has stronger anti-pollution and anti-blockage capacity and more stable operation.

The filter element of the ultrafilter in the application should preferably adopt PTFE material because it is better in corrosion-resistant, pollution-resistant and temperature-resistant performance.

The blowing-off device preferably adopts a rotary foam separation method, is operated at normal temperature and normal pressure, has higher mass transfer efficiency, stronger anti-blocking and anti-scaling capacity, lower cost and more convenient operation and maintenance.

In the application, the deamination membrane in the ammonia absorber adopts a hollow fiber membrane, the inner diameter of the hollow fiber microporous hydrophobic membrane is 100-2000 mu m, the wall thickness is 30-600 mu m, the microporous porosity of the membrane wall is 30-75%, the micropores are 0.01-1.0 mu m, the effective length is 20-200 cm, and the filling density of the hollow fiber membrane in the membrane component is 0.20-0.70.

The deamination membrane component is preferably made of PP (polypropylene), and under the current technical condition, the deamination membrane made of PP is more mature in application and more stable in operation.

The alkali liquor is preferably supplemented with sodium hydroxide solution, and the alkali liquor can be added in a tank or a pipe.

The absorption liquid can adopt acid absorption liquid such as dilute sulfuric acid, dilute phosphoric acid, dihydric phosphate and the like. Preferably, 20 to 30 percent (wt%) of dilute sulfuric acid is used, because dilute sulfuric acid is safer and has less heat of reaction to prevent the excessive temperature of the deamination film. In addition, because the raw water for preparing the acid contains a large amount of sulfate ions, new ions cannot be introduced when the ammonium sulfate solution generated by absorbing ammonia gas by the deamination film flows back. For example, phosphoric acid may cause the total phosphorus in the effluent to exceed the standard.

The advanced oxidation method can adopt photocatalytic oxidation, ozone catalytic oxidation and the like. Because the salt concentration range in the acid-making wastewater is 100-300 g/L, a biochemical process cannot be selected, and multiple pilot-scale studies show that the COD in the wastewater is not removed by a common electrochemical oxidation process or medicament oxidation such as Fenton oxidation, so that only an advanced catalytic oxidation process can be selected.

More specifically, the sewage to be removed by the technical scheme is complex acidic sewage with high elemental sulfur, high suspended matters, high COD, high ammonia nitrogen, high heavy metal content, high chlorine content and high salt content.

In the technical scheme, suspended matters and elemental sulfur are removed in a water quality adjusting device.

The main component of suspended matters in the sewage is activated carbon powder which enters the analysis gas after being heated and analyzed, and the activated carbon powder is analyzed and detected to adsorb elemental sulfur. If the activated carbon is not removed before neutralization, the elemental sulfur in the activated carbon powder is dissolved into the sewage in the neutralization process. Because of this, it is possible to reduce the number of the,

elemental sulfur undergoes a disproportionation reaction under alkalinity and further reacts with sulfite in the sewage to form thiosulfate.

The reaction involved is as follows:

3S+6OH^-＝2S^2-+SO3^2-+3H₂O

2S^2-+4SO₃ ^2-+6H⁺＝3S₂O₃ ^2-+3H₂O

the harm of the dissolved elemental sulfur entering the sewage is mainly to cause the blockage of a deamination film in the deamination film process. Although the deamination membrane is a hydrophobic breathable membrane, a small amount of sewage still enters the absorption liquid side due to the existence of osmotic pressure inside and outside membrane filaments, the absorption liquid is generally acidic and provides H & lt + & gt for reaction, the precipitated chalcogen is sulfur colloid and has the size of 1-100 nm, and the deamination membrane is difficult to be completely removed even if passing through a cartridge filter along with the recycling of absorption acid, and then crystals grow in the deamination membrane to cause the blockage of the deamination membrane.

S₂O₃ ^2-+2H⁺＝S+SO₂+H₂O

According to the actual process condition, the active carbon powder adopted in the sintering flue gas purification is mostly coal active carbon powder, the density is high, the active carbon powder is found to be easy to settle when standing in the actual engineering, and the particle size is small due to the fact that the particle size is centrally distributed between 5-50 microns, and the particle size is easy to float everywhere when being disturbed by external force. Therefore, the activated carbon powder can be well removed by adopting precipitation, and vertical flow type precipitation and inclined tube (inclined plate) precipitation are preferred, and mud scraping equipment is not required to be equipped.

And secondly, in the technical scheme, the heavy metal in the sewage is removed through a metal element precipitation device.

In this application, the first oxidation pond main part is that the ferrous hydroxide that will add the alkali production in the first neutralization pond deposits the oxidation into ferric hydroxide and deposits, improves the settling properties of metal deposit, improves the speed of deposit. This is mainly because the sludge volume formed by ferrous hydroxide is several times larger than that of ferric hydroxide sludge, resulting in a lower precipitation rate of ferrous hydroxide than ferric hydroxide. Wherein, first oxidation pond adopts the air as the oxidant because under current technical condition, can be used for the deamination membrane product material of engineering for a long time steadily mainly be polypropylene, and polypropylene oxidation resistance is relatively poor, if adopt other oxidants, such as ozone, hydrogen peroxide solution etc. there is the risk of oxidation deamination membrane.

Fe²⁺+OH-＝Fe(OH)₂↓

4Fe(OH)₂+O₂+2H₂O＝4Fe(OH)₃↓

Wherein the oxidation tank (tank) is located after the neutralization tank (tank) because the oxidation rate of ferrous iron to ferric iron proceeds very slowly at a pH below 6. Practice also proves that the air is directly blown into the acid making sewage with the pH value of 1-2 without adding alkaline solution, and ferrous ions are basically not oxidized.

In this application, ferric hydroxide is a good flocculant by itself, so no further flocculant needs to be added to the process. Sodium carbonate is added while air is aerated in the oxidation tank (groove), so that the sodium carbonate and the sewage can be better mixed by utilizing the stirring effect of the air, and the calcium and the magnesium can be better removed.

And thirdly, in the technical scheme, ammonia in the sewage is removed through an ammonia removal device.

In the first neutralization tank, the first alkali addition is required to meet the requirement of oxidation, and preferably the pH is controlled to be 9-10, and the second alkali supplement is required to meet the requirement of subsequent deamination, so that the pH is controlled to be 10-13, and preferably the pH is controlled to be 11-12. At the same time, the location of the second alkali supplementation is important, and care must be taken before, but not after, ultrafiltration. Because the ultrafiltration effluent contains a certain amount of dissolved metal ions, if alkali is supplemented again, the dissolved metal ions are separated out again, and frequent blockage of the security filter and the deamination membrane is caused. The practical application has been proved.

In addition, different processes are adopted according to the production requirements of different byproducts, the application range of the process can be expanded from the practical aspect, and the process has stronger engineering significance.

For example, for steel and iron enterprises with coking plants, the coking plants generally have ammonium sulfate concentration and crystallization processes, so dilute sulfuric acid can be directly used as an absorption liquid of a deamination membrane component without high-efficiency stripping to generate an ammonium sulfate product, and the ammonium sulfate product is transported to the coking plants to be concentrated and crystallized to produce nitrogen fertilizers. Not only solves the problem of the ammonium sulfate destination, but also does not need to add a set of equipment for concentration and crystallization, thereby greatly reducing the investment cost.

However, for steel enterprises without coking plants, a process combining high-efficiency stripping and deamination membrane is recommended, the high-efficiency stripping can only reduce the ammonia nitrogen concentration from 10000-20000 mg/L to 300-500 mg/L generally, and the deamination membrane can reduce the ammonia nitrogen concentration from 300-500 mg/L to less than 100mg/L, less than 15mg/L or less than 5 mg/L. Meanwhile, byproducts generated by the deamination film can be mixed with the incoming water to enter a high-efficiency stripping process because of less amount, the stable operation of high-efficiency stripping cannot be influenced, and 1-3% of ammonia generated by high-efficiency stripping can be recycled to the activated carbon adsorption process for denitration of sintering flue gas.

And fourthly, in the technical scheme, removing COD in the water by using a deep oxidation device.

According to the scheme, the traditional blowing-off process and the novel membrane method deamination process are combined for removing ammonia nitrogen in wastewater, the deamination process and the advanced oxidation method are combined for removing COD, and the COD is removed by adopting the advanced oxidation method after the deamination reaches the standard, so that the treatment load of the advanced oxidation method is greatly reduced, and the investment cost is saved; on the other hand, the treatment efficiency of the advanced oxidation method is also improved.

If the advanced oxidation method is placed in front of the deamination, hydroxyl radicals generated by the advanced oxidation can not only oxidize COD, but also oxidize ammonia nitrogen, but the removal effect of the COD and the ammonia nitrogen is poor, namely the existence of the high ammonia nitrogen influences the efficiency of removing the COD by the advanced oxidation method. Meanwhile, when the ammonia nitrogen concentration entering the advanced oxidation process is increased due to fluctuation of the deamination effect, the advanced oxidation process is taken as security, the ammonia nitrogen with a certain concentration can be oxidized and decomposed to reach the standard, the special description of effluent is not influenced, the acid production wastewater has extremely complex water quality, no ready-made process reference exists in the world, and related wastewater treatment processes are only submitted and disclosed by people like Yangbao, Liuyi and the like in 2017 of the company at present, and the detail is CN108002580A, namely an acid flue gas washing wastewater treatment method and application thereof, and compared with the acid production wastewater treatment process: besides the innovative improvements in the above places, the invention has the outstanding innovative points that:

(1) when the byproduct absorption liquid generated by deamination does not go out, high-efficiency blowing-off and membrane deamination are combined, the waste absorption liquid generated by the membrane deamination flows back to the high-efficiency blowing-off process, the absorption liquid byproduct is converted into about 1-3% of ammonia gas, and the ammonia gas is directly blown into an active carbon adsorption tower by a fan for deamination. Because the process is a wastewater treatment process matched with activated carbon flue gas purification, the internal recycling solves the problem of resource recovery of ammonia gas, and no worry of no place placement of absorption liquid exists. This is a model of circular economy and greatly expands the application range of the process.

(2) According to the requirements of the discharge standard of pollutants for water in the steel industry (GB 13456-. The COD value of the acid-making wastewater is measured to be about 300mg/L after the acid-making wastewater is qualified by deamination in practice. According to the invention, firstly, the ammonia removal reaches the standard and then the advanced oxidation method is adopted to remove COD, so that on one hand, the treatment load of the advanced oxidation method is greatly reduced, the investment cost is saved, and on the other hand, the treatment efficiency of the advanced oxidation method is also improved. Meanwhile, when the ammonia nitrogen concentration entering the advanced oxidation process is increased due to fluctuation of the deamination effect, the advanced oxidation process is used as security, ammonia nitrogen with certain concentration can be oxidized and decomposed to reach the standard, and the quality of effluent water is not affected.

(3) The use of an oxidant in the deamination process requires special caution because oxidants other than oxygen can cause aging of the deamination film and it is reasonable to select aeration oxidation in the present invention. However, air oxidation of ferrous hydroxide consumes a large amount of alkalinity, so when the pH value is less than 5, the ferrous hydroxide hardly reacts with oxygen in the air, because air aeration oxidation is not feasible under acidic conditions, and good oxidation effect can be achieved only by neutralizing and adding the alkalinity while air aeration or increasing the pH to be more than 9 at one time. The engineering usually chooses to raise the pH to above 9 and then aerate to deoxidize ferrous iron. The method is also a local water quality obviously different from the method for treating the acidic flue gas washing wastewater and the application thereof.

The technical scheme provided by the invention has the following innovation points:

1. the sintering and activated carbon flue gas desulfurization device, the acid making system and the wastewater treatment system are cooperatively designed, so that zero discharge of three wastes and resource utilization are realized, and the repeated setting of the system process is avoided.

2. The waste water in the treatment process in the waste water treatment system is subjected to acid-base sectional treatment and respectively recycled water reuse

2. Acid-base waste gas generated in the wastewater treatment system is separately collected and respectively subjected to resource recycling

3. Acid-base sludge generated in the wastewater treatment system is dewatered separately and is recycled uniformly

4. The combination of high-efficiency stripping and membrane deamination can recover ammonia gas and directly recycle the ammonia gas to an adsorption tower for deamination without the problems of waste ammonium sulfate and waste ammonia water

5. According to the problems in the prior art, the invention provides a new technical scheme, which specifically comprises the following steps: detail 1: removing ammonia and COD; detail 2: ensuring the pH of the acid-making wastewater to be acidic; detail 3: before entering ultrafiltration, the pH value of the wastewater must be adjusted in advance once; detail 4, filtering device could not be used after acid precipitation; detail 5, oxidation of ferrous ions before deamination membrane can only use air, but not other oxidants.

Compared with the prior art, the invention has the following beneficial effects:

1. compared with the prior art, the method only adopts precipitation to remove the activated carbon powder, does not need mud scraping equipment or filtering equipment, is simple to operate and maintain, reduces equipment failure points and investment cost, and can achieve better engineering operation effect.

2. Compared with the prior art, because other oxidants such as ozone, hydrogen peroxide and the like can cause irreversible damage to the deamination film, air is used as the oxidant, and the production cost is saved.

3. Compared with the prior art, the ferrous hydroxide precipitate can be effectively converted into the ferric hydroxide precipitate by neutralization and oxidation, so that the sedimentation performance is improved, and the production efficiency is improved.

4. Compared with the prior art, the addition of flocculating agents such as PAM can significantly cause the blockage of ultrafiltration, cartridge filters and deamination membranes, and the running cost is increased. Thus, the flocculation property of the ferric hydroxide is utilized to accelerate the overall precipitation effect.

5. Compared with the prior art, the stirring device can be saved and the investment and the operation cost can be reduced by utilizing the mixing and stirring effect generated when the air is aerated to oxidize the ferrous iron.

6. Compared with the prior art, the secondary alkali supplement after ultrafiltration can cause frequent blockage of a security filter and a deamination membrane.

7. Compared with the prior art, the process can effectively solve the problem of removing the deamination byproduct. The process combining the high-efficiency stripping and the deamination membrane solves the problem that the sewage can not be deaminated to reach the standard by the high-efficiency stripping and also solves the problem that waste absorption liquid generated in the deamination membrane process cannot be removed, realizes complementation and greatly enlarges the application range of the process.

Drawings

FIG. 1 is a schematic overall flow chart of a zero discharge process of activated carbon flue gas purification acid production wastewater in an embodiment of the invention;

FIG. 2 is a schematic view of the overall structure flow of the system for zero discharge of wastewater from acid production by activated carbon flue gas purification in the embodiment of the present invention;

FIG. 3 is a detailed process diagram of a zero discharge system for acid production wastewater from activated carbon flue gas purification in an embodiment of the present invention;

FIG. 4 is a schematic diagram of a detailed process of an alkali liquor replenishing device in the zero discharge system for purifying the acid-making wastewater by using the activated carbon flue gas in the embodiment of the invention;

FIG. 5 is a detailed flow diagram of a blow-off device in the zero discharge system for purifying the acid-making wastewater by using the activated carbon flue gas in the embodiment of the invention;

fig. 6 is a schematic structural diagram of an ammonia absorber of the zero discharge system for purifying the acid making wastewater by using the activated carbon flue gas in the embodiment of the invention.

Reference numerals:

1: an acid precipitation unit; 101: a water quality adjusting device; 2: a metal element precipitation device; 201: a first neutralization tank; 202: a first oxidation tank; 203: a flocculation sedimentation tank; 3: an ammonia removal device; 301: an ultrafilter; 302: a cartridge filter; 303: an ammonia absorber; 30301: a deamination reaction chamber; 30302: a deamination film; 30303: an absorption liquid inlet; 30304: an absorption liquid discharge port; 304: an alkali liquor replenishing device; 305: a blow-off device; 4: a deep oxidation device; 401: a second oxidation tank; 402: a second neutralization tank; 5: an acid gas recovery unit; 6: an ammonia gas recovery device; 7: a bottom sludge deacidification dehydration device; 8: a bottom mud alkaline-removing dehydration device;

l0: a raw sewage pipeline; l1: a first conduit; l2: a second conduit; l3: a third pipeline; l4: a fourth conduit; l5: a fifth pipeline; l6: a sixth pipeline; l7: a seventh pipe; l8: an eighth conduit; l9: a ninth conduit; l10: a tenth conduit; l11: an eleventh pipe; l12: a twelfth duct; l is_Acid(s): an acid gas return duct; l is_{Acid mud}: an acidic sludge pumping pipe; l is_Ammonia: an ammonia return air pipeline; l is_{Alkali mud}: and (4) an alkaline mud pumping pipe.

A1: an activated carbon desorption tower; a2: an activated carbon adsorption tower; a3: a spray tower of an acid making system; a: industrial waste water; b: alkali liquor; c: air; d: sodium carbonate; e: water; f: sintering and batching; g: absorbing the liquid.

Detailed Description

1) precipitating the acid-making complex sewage in an acid precipitation device 1, wherein gas generated in the precipitation process passes through an acid gas return air pipeline L_Acid(s)And enters an acid gas recovery device 5 for recovery.

2) And (2) introducing the acid-making complex sewage precipitated by the acid precipitation device 1 into a first neutralization tank 201, a first oxidation tank 202 and a flocculation precipitation tank 203 of the metal ion precipitation device 2 in sequence for metal ion precipitation, and allowing ammonia gas generated in the first neutralization tank 201, the first oxidation tank 202 and the flocculation precipitation tank 203 to enter an ammonia gas recovery device 6 for recovery.

3) And (3) introducing the acid-making complex sewage precipitated by the flocculation sedimentation tank 203 into an ammonia removal device 3 through a tenth pipeline L10 for ammonia removal, and removing ammonia from the acid-making complex sewage in the ammonia removal device 3 sequentially through an ultrafilter 301, a cartridge filter 302 and an ammonia absorber 303.

4) The acid-making complex sewage after ammonia removal by the ammonia absorber 303 is firstly introduced into a second oxidation tank 401 of the deep oxidation device 4 for oxidation, and then introduced into a second neutralization tank 402 for neutralization reaction to generate the industrial water for standby. The industrial water is used for sintering mixed materials or slag flushing in steel works.

In the step 1), the acidic bottom sludge generated in the acidic precipitation device 1 is introduced into the bottom sludge deacidification and dehydration device 7, the acidic filtrate generated in the bottom sludge deacidification and dehydration device 7 is recovered through a fifth pipeline L5, and the deacidified sludge generated in the bottom sludge deacidification and dehydration device 7 is recovered through a sixth pipeline L6.

Preferably, in step 2), the alkaline bottom sludge produced by the flocculation sedimentation tank 203 is introduced into the bottom sludge alkaline-removal dewatering device 8, the alkaline filtrate produced in the bottom sludge alkaline-removal dewatering device 8 is recovered through a seventh pipeline L7, and the dealkalized sludge produced in the bottom sludge alkaline-removal dewatering device 8 is recovered through an eighth pipeline L8.

Preferably, in step 3), lye is added to the tenth conduit L10 through lye supplementing device 304.

Preferably, in step 3), the acid production wastewater is first introduced into the ammonia removal device 3 to be subjected to ammonia removal by blowing in the blowing device 305, and then ammonia is removed sequentially through the ultrafilter 301, the cartridge filter 302, and the ammonia absorber 303.

Preferably, the absorption liquid produced in the ammonia absorber 303 is introduced into a stripping apparatus 305 to strip ammonia.

Preferably, the ammonia gas discharged from the stripping apparatus 305 is introduced into an activated carbon adsorption tower through an eleventh pipeline L11 to adsorb nitrogen oxides.

Preferably, in step 1), the acid production complex wastewater is first introduced into the water quality adjusting device 101 to adjust the water quality, and then introduced into the acid precipitation device 1 to precipitate. The acid gas generated by the water quality adjusting device 101 is led into an acid gas return pipeline L through a twelfth pipeline L12_Acid(s)To recover sulfur resources.

Preferably, in step 1), the acid gas collected in the acid gas recovery unit 5 is introduced into the spray tower of the acid making system through the first pipeline L1 to perform spray adsorption acid making.

Preferably, in step 1), the supernatant produced in the acidic precipitation device 1 is passed through a ninth pipeline L9 to the spray tower of the acid making system to adsorb acid gas.

Preferably, in step 1), the fifth line L5 is led to the water quality control device 101 and recovered, and the water quality control device 101 controls the acidic filtrate generated in the bottom sediment deacidification dehydration unit 7.

Preferably, the sixth pipeline L6 is led into a sintering batching device for recycling, and the produced deacidified sludge is used for sintering batching.

Preferably, in the step 2), the seventh pipeline L7 is led to the first neutralization tank 201 for recycling, and the alkaline filtrate generated in the bottom sediment alkaline dewatering device 8 is neutralized by the first neutralization tank 201.

Preferably, the eighth pipeline L8 is led into a sintering batching device for recycling, and the generated dealkalized sludge is used for sintering batching to recycle iron resources.

Preferably, in the step 2), the ammonia gas recovered by the ammonia gas recovery device 6 is introduced into the activated carbon adsorption tower through the second pipeline L2 to adsorb nitrogen oxides.

the utility model provides an active carbon gas cleaning system acid waste water zero discharge system, this system includes: the device comprises an acid precipitation device 1, a metal ion precipitation device 2, an ammonia removal device 3, a deep oxidation device 4, an acid gas recovery device 5 and an ammonia gas recovery device 6. The complex sewage for acid production is treated by the acid precipitation device 1, the metal ion precipitation device 2, the ammonia removal device 3 and the deep oxidation device 4 in sequence and then recycled or discharged. The acid-making complex sewage is communicated with the acid precipitation device 1 through a raw sewage pipeline L0. The acid gas return duct L of the acid gas recovery device 5_Acid(s)Is communicated with the exhaust port of the acid precipitation device 1. The exhaust outlet of the acid gas recovery device 5 is communicated with the first pipe L1. Ammonia air return pipeline L of ammonia recovery device 6_AmmoniaIs communicated with the exhaust port of the metal ion precipitation device 2. The exhaust outlet of the ammonia gas recovery device 6 is communicated with the second pipe L2.

Preferably, the metal ion precipitation device 2 includes: a first neutralization pond 201, a first oxidation pond 202 and a flocculation sedimentation pond 203. The liquid inlet of the first neutralization pond 201 is communicated with the liquid outlet of the acid precipitation device 1. The sewage passing through the acid precipitation device 1 sequentially passes through a first neutralization tank 201, a first oxidation tank 202 and a flocculation precipitation tank 203 in the metal ion precipitation device 2. The first oxidation pond 202 is provided with an oxide inlet. The first oxidation pond 202 is provided with a precipitator inlet.

Preferably, the ammonia return air duct L of the ammonia recovery device 6_AmmoniaThe exhaust port communication with the metal ion precipitation device 2 is specifically as follows: ammonia air return pipeline L of ammonia recovery device 6_AmmoniaCommunicating with the exhaust port of the first neutralization tank 201.

Preferably, the exhaust port of the first oxidation pond 202 is connected to the ammonia return pipeline L through a third pipeline L3_AmmoniaAnd/or the exhaust port of the flocculation sedimentation tank 203 is connected into an ammonia return air pipeline L through a fourth pipeline L4_Ammonia。

Preferably, the system further comprises: a bottom sludge deacidification dehydration device 7. Acid sludge pumping pipe L of bottom sludge deacidification dehydration device 7_{Acid mud}Is communicated with a sludge discharge port of the acid precipitation device 1. The acid filtrate discharge port of the bottom sludge deacidification and dehydration device 7 is communicated with a fifth pipeline L5. The deacidification sludge discharge port of the bottom sludge deacidification and dehydration device 7 is communicated with a sixth pipeline L6.

Preferably, the system further comprises: and a bottom mud alkali-removing dehydration device 8. Alkaline sludge pumping pipe L of bottom sludge alkaline-removing dehydration device 8_{Alkali mud}Is communicated with a sludge discharge port of the flocculation sedimentation tank 203. The basic filtrate discharge port of the bottom sludge alkaline-removal dewatering device 8 communicates with a seventh pipe L7. The dealkalized sludge discharge port of the bottom sludge dealkalized dewatering device 8 is communicated with an eighth pipeline L8.

Preferably, the clear precipitate liquid outlet of the acid precipitation device 1 is communicated to the spray liquid supplement inlet of the spray tower of the acid making system through a ninth pipeline L9.

Preferably, the first pipeline L1 is communicated to an inlet of a flue gas pipeline to be adsorbed of a spray tower of the acid making system.

Preferably, the second pipeline L2 is communicated to the flue gas inlet of the activated carbon adsorption tower.

Preferably, the liquid outlet of the flocculation sedimentation tank 203 is communicated with the liquid inlet of the ammonia removal device 3 through a tenth pipeline L10. The ammonia removal device 3 includes an ultrafilter 301, a cartridge filter 302, and an ammonia absorber 303. The sewage passing through the metal ion precipitation device 2 is treated by an ultrafilter 301, a cartridge filter 302 and an ammonia absorber 303 in turn in an ammonia removal device 3 and then enters a deep oxidation device 4.

Preferably, the ammonia absorber 303 includes: a deamination reaction chamber 30301, a deamination membrane 30302, a dilute acid inlet 30303 and an absorption liquid outlet 30304. A deamination membrane 30302 is disposed within deamination reaction chamber 30301. An absorption liquid inlet 30303 is arranged on the deamination reaction chamber 30301 at one side of the deamination membrane 30302. An absorption liquid discharge port 30304 is provided on the deamination reaction chamber 30301 located on the other side of the deamination membrane 30302. The sewage passes through the cavity on one side of the absorption liquid inlet 30303 in the deamination reaction cavity 30301 and then enters the deep oxidation device 4.

Preferably, the ammonia removal device 3 further includes: a lye supplementing device 304. The liquid outlet of the lye supplementing device 304 is communicated to a tenth pipeline L10.

Preferably, a second pH detecting sensor is disposed on the tenth pipe L10 downstream of the lye supplementing device 304.

Preferably, the ammonia removal device 3 further includes: a blow-off device 305. The blow-off means 305 is arranged upstream of the ultrafilter 301. The outlet of the flocculation tank 203 is communicated to the inlet of the stripping device 305 through a tenth pipeline L10. An ammonia gas outlet on the stripping device 305 is communicated with an eleventh pipeline L11.

Preferably, the absorbent outlet 30304 is connected to the blow-off device 305.

Preferably, an eleventh pipe L11 is connected to the flue gas inlet of the activated carbon adsorption tower.

Preferably, the system further comprises a water quality adjusting device 101, the water quality adjusting device 101 is arranged on the original sewage pipeline L0, and the acid production complex sewage is treated by the water quality adjusting device 101 and then enters the acid precipitation device 1.

Preferably, the exhaust outlet of the water quality control device 101 is connected to the acid gas return duct L through a twelfth duct L12_Acid(s)。

Preferably, the acid solution supply port of the water quality control device 101 is communicated with the fifth pipeline L5.

Preferably, the water quality control device 101 is provided with a water replenishing port. A first stirring mechanism is arranged in the water quality adjusting device 101.

Preferably, the acid precipitation tank 102 is provided with a suspended matter removing mechanism.

Preferably, the first neutralization tank 201 is provided with an alkali solution inlet and a first pH detection sensor.

Preferably, a second stirring mechanism is arranged in the flocculation sedimentation tank 203.

Preferably, the first stirring mechanism and the second stirring mechanism are air stirring devices or mechanical stirring devices. The oxidant inlet on the first oxidation tank 202 is in communication with air. The precipitator inlet on the first oxidation pond 202 is communicated with a carbonate storage device. The second oxidation pond 401 is a catalytic oxidation device.

Preferably, the deep oxidation apparatus 4 includes: a second oxidation pond 401 and a second neutralization pond 402. The sewage is treated by the second oxidation pond 401 and the second neutralization pond 402 in the deep oxidation device 4 in sequence and then is discharged outwards.

Preferably, a third pH detection sensor is provided on the second neutralization tank 402.

Example 1

1) precipitating the acid-making complex sewage in an acid precipitation device 1, wherein gas generated in the precipitation process passes through an acid gas return air pipeline L_Acid(s)The acid gas enters an acid gas recovery device 5 for recovery;

2) the acid-making complex sewage precipitated by the acid precipitation device 1 is sequentially introduced into a first neutralization tank 201, a first oxidation tank 202 and a flocculation precipitation tank 203 of a metal ion precipitation device 2 for metal ion precipitation, and ammonia gas generated in the first neutralization tank 201, the first oxidation tank 202 and the flocculation precipitation tank 203 enters an ammonia gas recovery device 6 for recovery;

3) leading the acid-making complex sewage precipitated by the flocculation sedimentation tank 203 into an ammonia removal device 3 through a tenth pipeline L10 for ammonia removal, and removing ammonia from the acid-making complex sewage in the ammonia removal device 3 through an ultrafilter 301, a cartridge filter 302 and an ammonia absorber 303 in sequence;

4) the acid-making complex sewage after ammonia removal by the ammonia absorber 303 is firstly introduced into a second oxidation tank 401 of the deep oxidation device 4 for oxidation, and then introduced into a second neutralization tank 402 for neutralization reaction to generate industrial water for standby; the industrial water to be used is used for sintering mixed materials or slag flushing in a steel mill;

Example 2

Example 1 is repeated except that in step 2), the alkaline bottom sludge produced in the flocculation sedimentation tank 203 is introduced into the bottom sludge dealkalization dewatering device 8, the alkaline filtrate produced in the bottom sludge dealkalization dewatering device 8 is recovered through a seventh pipeline L7, and the dealkalization sludge produced in the bottom sludge dealkalization dewatering device 8 is recovered through an eighth pipeline L8; in step 3), lye is added into the tenth pipeline L10 through the lye supplementing device 304.

Example 3

Example 2 is repeated except that in step 3), the acid production complex sewage is firstly introduced into the stripping device 305 in the ammonia removal device 3 for stripping ammonia, and then ammonia is removed through the ultrafilter 301, the cartridge filter 302 and the ammonia absorber 303 in sequence. Introducing the absorption liquid generated in the ammonia absorber 303 into a stripping device 305 for stripping ammonia; the ammonia gas discharged from the stripping device 305 is introduced into an activated carbon adsorption tower through an eleventh pipeline L11 to adsorb nitrogen oxides.

Example 4

Example 3 is repeated except that in the step 1), the acid-making complex sewage is firstly introduced into the water quality to be adjustedAfter the water quality is regulated in the device 101, the water is introduced into the acid precipitation device 1 for precipitation; the acid gas generated by the water quality adjusting device 101 is led into an acid gas return pipeline L through a twelfth pipeline L12_Acid(s)To recover sulfur resources.

Example 5

Example 4 is repeated except that in step 1), the acid gas collected in the acid gas recovery device 5 is introduced into the spray tower of the acid making system through the first pipeline L1 for spray adsorption to make acid; in the step 1), the supernatant produced in the acidic precipitation device 1 is introduced into a spray tower of an acid making system through a ninth pipeline L9 to adsorb acidic gas.

Example 6

Example 5 was repeated except that in step 1), the fifth line L5 was introduced into the water quality control device 101 and recovered, and the acid filtrate produced in the bottom sediment deacidification dehydration unit 7 was controlled by the water quality control device 101. The sixth pipeline L6 is led into a sintering batching device for recycling, and the produced deacidified sludge is used for sintering batching.

Example 7

Example 6 is repeated except that in step 2), the seventh line L7 is led to the first neutralization tank 201 for recovery, and the alkaline filtrate produced in the bottom sediment alkaline dewatering device 8 is neutralized by the first neutralization tank 201. And introducing the eighth pipeline L8 into a sintering batching device for recycling, and using the generated dealkalized sludge for sintering batching to recycle iron resources.

Example 8

Example 7 was repeated except that in step 2), the ammonia gas recovered by the ammonia gas recovering device 6 was introduced into the activated carbon adsorption tower through the second line L2 to adsorb nitrogen oxides.

Example 9

The utility model provides an active carbon gas cleaning system acid waste water zero discharge system, this system includes: the device comprises an acid precipitation device 1, a metal ion precipitation device 2, an ammonia removal device 3, a deep oxidation device 4, an acid gas recovery device 5 and an ammonia gas recovery device 6; the complex acid-making sewage is treated by the acid precipitation device 1, the metal ion precipitation device 2, the ammonia removal device 3 and the deep oxidation device 4 in sequence and then recycled or discharged; acid makingThe complex sewage is communicated with the acid precipitation device 1 through an original sewage pipeline L0; the acid gas return duct L of the acid gas recovery device 5_Acid(s)Is communicated with the exhaust port of the acid precipitation device 1; the exhaust outlet of the acid gas recovery device 5 is communicated with a first pipeline L1; ammonia air return pipeline L of ammonia recovery device 6_AmmoniaIs communicated with the exhaust port of the metal ion precipitation device 2; the exhaust outlet of the ammonia gas recovery device 6 is communicated with the second pipe L2.

Example 10

Example 9 was repeated except that the metal ion precipitation apparatus 2 included: a first neutralization tank 201, a first oxidation tank 202 and a flocculation sedimentation tank 203; the liquid inlet of the first neutralization pond 201 is communicated with the liquid outlet of the acid precipitation device 1; the sewage passing through the acidic precipitation device 1 sequentially passes through a first neutralization tank 201, a first oxidation tank 202 and a flocculation precipitation tank 203 in a metal ion precipitation device 2; an oxide inlet is arranged on the first oxidation pond 202; the first oxidation pond 202 is provided with a precipitator inlet. Ammonia air return pipeline L of ammonia recovery device 6_AmmoniaThe exhaust port communication with the metal ion precipitation device 2 is specifically as follows: ammonia air return pipeline L of ammonia recovery device 6_AmmoniaCommunicating with the exhaust port of the first neutralization tank 201. The exhaust port of the first oxidation pond 202 is connected into an ammonia return air pipeline L through a third pipeline L3_Ammonia. The exhaust port of the flocculation sedimentation tank 203 is connected with an ammonia return air pipeline L through a fourth pipeline L4_Ammonia。

Example 11

Example 10 is repeated except that the system further comprises: a bottom sludge deacidification dehydration device 7; acid sludge pumping pipe L of bottom sludge deacidification dehydration device 7_{Acid mud}Is communicated with a sludge discharge port of the acid precipitation device 1; an acid filtrate discharge port of the bottom sediment deacidification and dehydration device 7 is communicated with a fifth pipeline L5; the deacidification sludge discharge port of the bottom sludge deacidification and dehydration device 7 is communicated with a sixth pipeline L6. The system further comprises: a bottom sludge alkaline-removing dehydration device 8; alkaline sludge pumping pipe L of bottom sludge alkaline-removing dehydration device 8_{Alkali mud}Is communicated with a sludge discharge port of the flocculation sedimentation tank 203; the alkaline filtrate discharge port of the bottom sediment alkaline-removal dewatering device 8 is communicated with a seventh pipeline L7; dealkalized sludge discharge of bottom sludge dealkalization dehydration device 8The outlet is in communication with an eighth conduit L8.

Example 12

Example 11 was repeated except that the precipitated clear liquid drain port of the acid precipitation device 1 was communicated to the spray liquid supply port of the spray tower of the acid making system through the ninth pipe L9. The first pipeline L1 is communicated to an inlet of a flue gas pipeline to be adsorbed of a spray tower of the acid making system. The second pipe L2 communicates to the flue gas inlet of the activated carbon adsorption tower.

Example 13

Example 12 is repeated, except that the liquid outlet of the flocculation sedimentation tank 203 is communicated with the liquid inlet of the ammonia removal device 3 through a tenth pipeline L10; the ammonia removal device 3 comprises an ultrafilter 301, a cartridge filter 302 and an ammonia absorber 303; the sewage passing through the metal ion precipitation device 2 is treated by an ultrafilter 301, a cartridge filter 302 and an ammonia absorber 303 in turn in an ammonia removal device 3 and then enters a deep oxidation device 4. The ammonia absorber 303 includes: a deamination reaction cavity 30301, a deamination membrane 30302, a dilute acid inlet 30303 and an absorption liquid outlet 30304; the deamination membrane 30302 is arranged in the deamination reaction chamber 30301; an absorption liquid inlet 30303 is arranged on the deamination reaction cavity 30301 at one side of the deamination membrane 30302; an absorption liquid discharge port 30304 is arranged on the deamination reaction chamber 30301 positioned on the other side of the deamination membrane 30302; the sewage passes through the cavity on one side of the absorption liquid inlet 30303 in the deamination reaction cavity 30301 and then enters the deep oxidation device 4.

Example 14

Example 13 was repeated except that the ammonia removal unit 3 further included: a lye supplementing device 304; the liquid outlet of the lye supplementing device 304 is communicated to a tenth pipeline L10. A second pH detection sensor is arranged on the tenth pipeline L10 downstream of the lye supplementation device 304. The ammonia removal device 3 further includes: a blow-off device 305; the blow-off device 305 is arranged upstream of the ultrafilter 301; the liquid outlet of the flocculation sedimentation tank 203 is communicated to the liquid inlet of the stripping device 305 through a tenth pipeline L10; an ammonia gas outlet on the stripping device 305 is communicated with an eleventh pipeline L11. The absorption liquid discharge port 30304 is communicated to the stripping device 305. An eleventh duct L11 communicates to the flue gas inlet of the activated carbon adsorption column.

Example 15

The embodiment 14 is repeated, except that the system further comprises a water quality adjusting device 101, the water quality adjusting device 101 is arranged on the original sewage pipeline L0, and the acid production complex sewage is treated by the water quality adjusting device 101 and then enters the acid precipitation device 1. The exhaust outlet of the water quality adjusting device 101 is connected to the acid gas return pipeline L through a twelfth pipeline L12_Acid(s). The acid liquor replenishing port of the water quality adjusting device 101 is communicated with a fifth pipeline L5. A water replenishing port is arranged on the water quality adjusting device 101; a first stirring mechanism is arranged in the water quality adjusting device 101. The acid settling tank 102 is provided with a suspended matter removing mechanism.

Example 16

Example 15 was repeated except that the first neutralization tank 201 was provided with an alkali solution inlet and a first pH detecting sensor. A second stirring mechanism is arranged in the flocculation sedimentation tank 203.

Example 17

Example 16 was repeated except that the first stirring mechanism and the second stirring mechanism were air stirring devices or mechanical stirring devices; the oxide inlet on the first oxidation pond 202 is communicated with air; a precipitator inlet on the first oxidation pond 202 is communicated with a carbonate storage device; the second oxidation pond 401 is a catalytic oxidation device.

Example 18

Example 17 was repeated except that the deep oxidation apparatus 4 included: a second oxidation tank 401, a second neutralization tank 402; the sewage is treated by the second oxidation pond 401 and the second neutralization pond 402 in the deep oxidation device 4 in sequence and then is discharged outwards. The second neutralization tank 402 is provided with a third pH detection sensor.

Claims

1. The activated carbon flue gas purification acid-making wastewater zero-discharge process is characterized by comprising the following steps of:

1) precipitating the acid-making complex sewage in an acid precipitation device (1), wherein gas generated in the precipitation process passes through an acid gas return air pipeline (L)_Acid(s)) The acid gas enters an acid gas recovery device (5) for recovery, and the acid gas collected in the acid gas recovery device (5) is introduced into a spray tower of an acid making system through a first pipeline (L1) for spraying and adsorbing to make acid;

2) the acid-making complex sewage precipitated by the acid precipitation device (1) is sequentially introduced into a first neutralization tank (201), a first oxidation tank (202) and a flocculation precipitation tank (203) of a metal ion precipitation device (2) for metal ion precipitation, ammonia gas generated in the first neutralization tank (201), the first oxidation tank (202) and the flocculation precipitation tank (203) enters an ammonia gas recovery device (6) for recovery, and the ammonia gas recovered by the ammonia gas recovery device (6) is introduced into an activated carbon adsorption tower through a second pipeline (L2) for adsorption of nitrogen oxides;

3) introducing the acid-making complex sewage precipitated by the flocculation sedimentation tank (203) into an ammonia removal device (3) through a tenth pipeline (L10) for ammonia removal, and removing ammonia from the acid-making complex sewage in the ammonia removal device (3) through an ultrafilter (301), a cartridge filter (302) and an ammonia absorber (303) in sequence;

4) leading the acid-making complex sewage subjected to ammonia removal by the ammonia absorber (303) into a second oxidation pond (401) of the deep oxidation device (4) for oxidation, and then leading the acid-making complex sewage into a second neutralization pond (402) for neutralization reaction to generate industrial water for standby; the industrial water to be used is used for sintering mixed materials or slag flushing in a steel mill;

in the step 1), firstly, introducing the acid-making complex sewage into a water quality adjusting device (101) for water quality adjustment, and then introducing the acid-making complex sewage into an acid precipitation device (1) for precipitation; the acid gas generated by the water quality adjusting device (101) is led into the acid gas return pipeline (L12) through the twelfth pipeline (L12)_Acid(s)) To recover sulfur resources; acid bottom sludge generated in the acid precipitation device (1) is introduced into a bottom sludge acidity removal dehydration device (7), acid filtrate generated in the bottom sludge acidity removal dehydration device (7) is recycled through a fifth pipeline (L5), deacidified sludge generated in the bottom sludge acidity removal dehydration device (7) is recycled through a sixth pipeline (L6), the sixth pipeline (L6) is introduced into a sintering batching device for recycling, and the generated deacidified sludge is used for sintering batching;

in the step 2), the alkaline bottom sludge generated by the flocculation sedimentation tank (203) is introduced into a bottom sludge alkaline-removal dehydration device (8), alkaline filtrate generated in the bottom sludge alkaline-removal dehydration device (8) is recycled through a seventh pipeline (L7), dealkalized sludge generated in the bottom sludge alkaline-removal dehydration device (8) is introduced into a sintering batching device through an eighth pipeline (L8) for recycling, and the generated dealkalized sludge is used for sintering batching to recycle iron resources.

2. The activated carbon flue gas purification acid making wastewater zero discharge process as claimed in claim 1, wherein in the step 3), alkali liquor is added into the tenth pipeline (L10) through an alkali liquor supplementing device (304).

3. The activated carbon flue gas purification acid production wastewater zero discharge process according to claim 1, characterized in that in the step 3), the acid production complex sewage is firstly introduced into the stripping device (305) in the ammonia removal device (3) for stripping ammonia, and then ammonia is removed sequentially through the ultrafilter (301), the cartridge filter (302) and the ammonia absorber (303).

4. The activated carbon flue gas purification acid-making wastewater zero-emission process as claimed in claim 3, wherein the absorption liquid generated in the ammonia absorber (303) is introduced into a stripping device (305) for stripping ammonia; and introducing ammonia gas discharged from the stripping device (305) into an activated carbon adsorption tower through an eleventh pipeline (L11) to adsorb nitrogen oxides.

5. The activated carbon flue gas purification acid production wastewater zero emission process as claimed in any one of claims 1 to 4, wherein in the step 1), the fifth pipeline (L5) is introduced into the water quality adjusting device (101) for recycling, and the acid filtrate generated in the bottom sludge deacidification dehydration device (7) is adjusted by the water quality adjusting device (101).

6. The activated carbon flue gas purification acid-making wastewater zero-emission process as claimed in claim 5, wherein in the step 2), the seventh pipeline (L7) is introduced into the first neutralization tank (201) for recycling, and the alkaline filtrate generated in the bottom sludge alkaline dehydration device (8) is neutralized by the first neutralization tank (201).

7. An activated carbon flue gas purification acid-making wastewater zero discharge system for the process of any one of claims 1 to 6, which is characterized by comprising: the device comprises an acid precipitation device (1), a metal ion precipitation device (2), an ammonia removal device (3), a deep oxidation device (4), an acid gas recovery device (5) and an ammonia gas recovery device (6); the acid-making complex sewage is treated by the acid precipitation device (1), the metal ion precipitation device (2), the ammonia removal device (3) and the deep oxidation device (4) in sequence and then recycled or discharged; the acid-making complex sewage is communicated with the acid precipitation device (1) through an original sewage pipeline (L0);

an acid gas return duct (L) of the acid gas recovery device (5)_Acid(s)) Is communicated with the exhaust port of the acid precipitation device (1); the exhaust outlet of the acid gas recovery device (5) is communicated with a first pipeline (L1);

ammonia air return pipeline (L) of ammonia recovery device (6)_Ammonia) Is communicated with the exhaust port of the metal ion precipitation device (2); an exhaust outlet of the ammonia gas recovery device (6) is communicated with a second pipeline (L2);

the metal ion precipitation device (2) comprises: a first neutralization pond (201), a first oxidation pond (202) and a flocculation sedimentation pond (203); the liquid inlet of the first neutralization pond (201) is communicated with the liquid outlet of the acid precipitation device (1); the sewage passing through the acidic precipitation device (1) sequentially passes through a first neutralization tank (201), a first oxidation tank (202) and a flocculation precipitation tank (203) in a metal ion precipitation device (2); an oxide inlet is arranged on the first oxidation pond (202); a precipitator inlet is arranged on the first oxidation pond (202);

the system further comprises: a bottom sludge deacidification dehydration device (7); acid sludge pumping pipe (L) of bottom sludge acid-removing dehydration device (7)_{Acid mud}) Is communicated with a sludge discharge port of the acid precipitation device (1); an acid filtrate discharge port of the bottom sediment deacidification and dehydration device (7) is communicated with a fifth pipeline (L5); the deacidification sludge discharge port of the bottom sludge deacidification and dehydration device (7) is communicated with a sixth pipeline (L6);

the system further comprises: a bottom mud alkaline-removing dehydration device (8); alkaline sludge pumping pipe (L) of bottom sludge alkaline-removing dehydration device (8)_{Alkali mud}) Is communicated with a sludge discharge port of the flocculation sedimentation tank (203); an alkaline filtrate discharge port of the bottom sediment alkaline-removal dehydration device (8) is communicated with a seventh pipeline (L7); the dealkalized sludge discharge port of the bottom sludge dealkalization dehydration device (8) is communicated with an eighth pipeline (L8).

8. The activated carbon flue gas purification acid-making wastewater zero discharge system as claimed in claim 7, wherein the ammonia return air pipeline (L) of the ammonia recovery device (6)_Ammonia) The exhaust port communicated with the metal ion precipitation device (2) is specifically as follows: ammonia air return pipeline (L) of ammonia recovery device (6)_Ammonia) Is communicated with the exhaust port of the first neutralization tank (201).

9. The system for zero discharge of wastewater from acid production by purification of activated carbon flue gas as claimed in claim 7 or 8, wherein the exhaust port of the first oxidation tank (202) is connected to the ammonia return air pipeline (L3) through a third pipeline (L3)_Ammonia）。

10. The system for zero discharge of wastewater from acid production by flue gas purification with activated carbon as claimed in claim 9, wherein the exhaust port of the flocculation sedimentation tank (203) is connected to the ammonia return air pipeline (L4) via a fourth pipeline (L4)_Ammonia）。