阅读说明：本技术 一种硫酸生产废水回收利用的方法 (Method for recycling sulfuric acid production wastewater ) 是由 黄帮义 于 2020-03-09 设计创作，主要内容包括：本发明属于废水回收处理领域,具体公开了一种硫酸生产废水回收利用的方法,包括：含硫废水预处理,处理后获得硫废水预处理液；含硫废水取样分析,获取预处理液中硫酸盐的浓度,并加入药剂中和,中和后生成初液；压滤与二次处理,将初液置入压滤装置内进行压滤,压滤后得到硫酸钙滤饼,压滤后的压滤废液进行二次处理；打浆处理,将硫酸钙滤饼置入打浆装置内进行打浆,打浆中加入水,打浆后形成硫酸钙浆液；将硫酸钙浆液置入反应桶中进行分解反应,反应生成反应液与处理液；将反应液与处理液置入压滤装置内进行二次压滤,并在压滤后进行结晶过滤。本发明的回收方法简单且易实现,同时在处理过程中生成的碳酸钙以及二氧化碳可作为回收产物使用。(The invention belongs to the field of wastewater recovery treatment, and particularly discloses a method for recycling sulfuric acid production wastewater, which comprises the following steps: pretreating sulfur-containing wastewater to obtain sulfur-containing wastewater pretreatment liquid; sampling and analyzing the sulfur-containing wastewater, obtaining the concentration of sulfate in the pretreatment liquid, adding a medicament for neutralization, and generating a primary liquid after neutralization; performing filter pressing and secondary treatment, namely putting the primary liquid into a filter pressing device for filter pressing to obtain a calcium sulfate filter cake after filter pressing, and performing secondary treatment on filter pressing waste liquid after filter pressing; pulping, namely putting the calcium sulfate filter cake into a pulping device for pulping, adding water into the pulping, and pulping to form calcium sulfate slurry; placing the calcium sulfate slurry into a reaction barrel for decomposition reaction to generate reaction liquid and treatment liquid; and (3) placing the reaction liquid and the treatment liquid into a filter pressing device for secondary filter pressing, and performing crystallization filtration after filter pressing. The recovery method is simple and easy to realize, and simultaneously, the calcium carbonate and the carbon dioxide generated in the treatment process can be used as recovery products.)

1. A method for recycling sulfuric acid production wastewater is characterized by comprising the following steps:

s1: pretreating sulfur-containing wastewater, namely pressing the sulfur-containing wastewater into a filtering treatment container through a pressure pump, filtering the sulfur-containing wastewater to remove fine suspended matters in the wastewater, and filtering to obtain sulfur-containing wastewater pretreatment liquid;

s2: sampling and analyzing sulfur-containing wastewater, namely sampling and analyzing a sulfur-containing wastewater pretreatment solution in S1 to obtain the concentration of sulfate in the pretreatment solution, adding a medicament for neutralization, and generating a primary solution after neutralization;

s3: filter pressing and secondary treatment, namely putting the primary liquid in the S2 into a filter pressing device for filter pressing to obtain a calcium sulfate filter cake, and performing secondary treatment on filter pressing waste liquid after filter pressing;

s4: pulping, namely putting the calcium sulfate filter cake into a pulping device for pulping, adding water into the pulping, wherein the mass ratio of the water to the filter cake is 2-4:4-5, and pulping to form calcium sulfate slurry;

s5: placing the calcium sulfate slurry in the reaction barrel of S4 for decomposition reaction to generate reaction liquid and treatment liquid;

s6: and (3) placing the reaction liquid and the treatment liquid into a filter pressing device for secondary filter pressing, and performing crystallization filtration after the secondary filter pressing.

2. The method for recycling sulfuric acid production wastewater according to claim 1, wherein the S2 traditional Chinese medicine is calcium carbonate, and S2 specifically comprises: s21: sampling and analyzing the sulfur wastewater pretreatment liquid to obtain the concentration of sulfate; s22: adding the sulfur wastewater pretreatment liquid into a reaction container, adding a calcium carbonate medicament into the container, stirring to neutralize the calcium carbonate medicament, and generating calcium sulfate primary liquid and carbon dioxide after neutralization reaction.

3. The method for recycling sulfuric acid production wastewater according to claim 1, wherein the secondary treatment of the pressure filtration waste liquor in the S3 comprises: and (3) putting the filter pressing waste liquid into a crystallization reaction vessel for separation, and separating calcium sulfate crystal particles and a separation liquid.

4. The method for recycling sulfuric acid production wastewater according to claim 1, wherein the step S5 specifically comprises: s51: placing the calcium sulfate slurry into a reaction barrel; s52: adding ammonium carbonate into the reaction barrel, and reacting the ammonium carbonate with calcium sulfate to generate reaction liquid and treatment liquid, wherein the reaction liquid and the treatment liquid are ammonium sulfate saturated liquid and calcium carbonate emulsion respectively.

5. The method for recycling sulfuric acid production wastewater according to claim 4, wherein the mass ratio of ammonium carbonate to calcium sulfate in S51 is 2-5: 6-8.

6. The method for recycling sulfuric acid production wastewater according to claim 1, wherein the step S6 specifically comprises: s61: placing the reaction liquid and the treatment liquid into a filter pressing device for secondary filter pressing to obtain a calcium carbonate filter cake and an ammonium sulfate saturated liquid; s62: putting the saturated ammonium sulfate solution into a crystallization reaction container for crystallization and precipitation; s63: and (4) putting the crystal separated out into a centrifugal machine for centrifugal filtration until solid-liquid separation of ammonium sulfate is carried out to obtain ammonium sulfate solid.

7. The method for recycling sulfuric acid production wastewater according to claim 2, wherein the carbon dioxide generated in the S22 can be used for preparing ammonium carbonate from ammonia and water.

Technical Field

The invention relates to the field related to wastewater recovery treatment, in particular to a method for recycling sulfuric acid production wastewater.

Background

Sulfuric acid is an important basic chemical raw material, is widely applied in the industries of chemical engineering, steel and the like, and is commonly used as a dehydrating agent, a reaction intermediate, a cleaning agent, a catalyst and the like in the industry. In many production processes, the utilization rate of sulfuric acid wastewater is low, and a large amount of sulfuric acid wastewater is discharged along with other wastewater; if the waste water is discharged into the environment without being treated, the water body or the soil can be acidified, the ecological environment is harmed, and a large amount of sulfuric acid resources are wasted.

Because the recovery cost of the sulfuric acid is high, many enterprises do not carry out recovery treatment on the sulfuric acid or discharge the sulfuric acid wastewater after adding the sulfuric acid wastewater into lime for neutralization treatment. These processes are not only costly, but also may cause environmental pollution and waste of resources.

Disclosure of Invention

The invention aims to provide a method for recycling sulfuric acid production wastewater, which aims to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme:

a method for recycling sulfuric acid production wastewater comprises the following steps:

s1: pretreating sulfur-containing wastewater, namely pressing the sulfur-containing wastewater into a filtering treatment container through a pressure pump, filtering the sulfur-containing wastewater to remove fine suspended matters in the wastewater, and filtering to obtain sulfur-containing wastewater pretreatment liquid;

s2: sampling and analyzing sulfur-containing wastewater, namely sampling and analyzing a sulfur-containing wastewater pretreatment solution in S1 to obtain the concentration of sulfate in the pretreatment solution, adding a medicament for neutralization, and generating a primary solution after neutralization;

s3: performing filter pressing and secondary treatment, namely putting the primary liquid into a filter pressing device for filter pressing to obtain a calcium sulfate filter cake after filter pressing, and performing secondary treatment on filter pressing waste liquid after filter pressing;

s4: pulping, namely putting the calcium sulfate filter cake into a pulping device for pulping, adding water into the pulping, wherein the mass ratio of the water to the filter cake is 2-4:4-5, and pulping to form calcium sulfate slurry;

s5: placing the calcium sulfate slurry in the reaction barrel of S4 for decomposition reaction to generate reaction liquid and treatment liquid;

s6: and (3) placing the reaction liquid and the treatment liquid into a filter pressing device for secondary filter pressing, and performing crystallization filtration after the secondary filter pressing.

As a preferred technical scheme of the invention, the S2 traditional Chinese medicine is calcium carbonate, and S2 specifically comprises: s21: sampling and analyzing the sulfur wastewater pretreatment liquid to obtain the concentration of sulfate; s22: adding the sulfur wastewater pretreatment liquid into a reaction container, adding a calcium carbonate medicament into the container, stirring to neutralize the calcium carbonate medicament, and generating calcium sulfate primary liquid and carbon dioxide after neutralization reaction.

As a preferable technical solution of the present invention, the secondary treatment of the pressure filtration waste liquid in S3 includes: and (3) putting the filter pressing waste liquid into a crystallization reaction vessel for separation, and separating calcium sulfate crystal particles and a separation liquid.

As a preferred technical solution of the present invention, S5 specifically includes: s51: placing the calcium sulfate slurry into a reaction barrel; s52: adding ammonium carbonate into the reaction barrel, and reacting the ammonium carbonate with calcium sulfate to generate reaction liquid and treatment liquid, wherein the reaction liquid and the treatment liquid are ammonium sulfate saturated liquid and calcium carbonate emulsion respectively.

As a preferable technical scheme of the invention, the mass ratio of ammonium carbonate to calcium sulfate in S51 is 2-5: 6-8.

As a preferred technical solution of the present invention, S6 specifically includes: s61: placing the reaction liquid and the treatment liquid into a filter pressing device for secondary filter pressing to obtain a calcium carbonate filter cake and an ammonium sulfate saturated liquid; s62: putting the saturated ammonium sulfate solution into a crystallization reaction container for crystallization and precipitation; s63: and (4) putting the crystal separated out into a centrifugal machine for centrifugal filtration until solid-liquid separation of ammonium sulfate is carried out to obtain ammonium sulfate solid.

As a preferable technical scheme of the invention, the carbon dioxide generated by S22 can be used for preparing ammonium carbonate from ammonia and water.

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

the recovery treatment method is simple and easy to implement, the recovery method is environment-friendly, sulfate in the wastewater can be recovered, sulfuric acid in the wastewater is separated, favorable conditions are created for biochemical treatment of the wastewater, and calcium carbonate and carbon dioxide generated in the treatment process can be used as recovery products, wherein the calcium carbonate can be repeatedly used in the recovery treatment method, the carbon dioxide can react with ammonia gas and water to generate ammonium carbonate salt, and the ammonium carbonate salt can be used as a chemical fertilizer, a printing and dyeing auxiliary agent and the like.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.