CN-121974463-A - High-salt wastewater medicament and preparation method and application thereof

Abstract

The invention relates to the technical field of wastewater treatment, in particular to a high-salt wastewater medicament, a preparation method and application thereof. The high-salt wastewater medicament comprises a calcium-containing compound, an aluminum source compound and a crystallization structure regulator, wherein the molar ratio of calcium element to aluminum element in the calcium-containing compound to the aluminum source compound is 2:1-4:1, and the mass of the crystallization structure regulator is 10-30% of the total mass of the high-salt wastewater medicament. When the reagent is applied, the reagent is added into high-salt wastewater with the chloride ion concentration of 5-25 g/L, and Freund salt precipitation is generated through calcium-aluminum synergistic reaction, so that the efficient fixation and removal of chloride ions are realized. The preparation has the advantages of simple components, low cost, high chlorine removal efficiency and wide applicable concentration range, and after the crystallization regulator is added, the French salt precipitate can also be quickly settled, so that the volume of the precipitate is greatly reduced.

Inventors

• HE DEWEN
• TIAN SISI
• HE ZHIYUAN
• LIU YOUMING
• SONG KE
• LI XIONG
• HU ZHEWEI
• WU XIA

Assignees

• 中南大学
• 湖南亿康环保科技有限公司

Dates

Publication Date

20260505

Application Date

20260330

Claims (8)

1. 1. The high-salt wastewater medicament is characterized by comprising a calcium-containing compound, an aluminum source compound and a crystallization structure regulator, wherein the molar ratio of calcium element to aluminum element in the calcium-containing compound to the aluminum source compound is 2:1-4:1, and the mass of the crystallization structure regulator is 10-30% of the total mass of the high-salt wastewater medicament.
2. 2. The high salt wastewater treatment agent of claim 1, wherein the calcium-containing compound is one or both of calcium oxide and calcium hydroxide.
3. 3. The high-salt wastewater medicament according to claim 1, wherein the aluminum source compound is one or more of sodium metaaluminate, aluminum hydroxide and aluminum oxide.
4. 4. The high salt wastewater agent of claim 1, wherein the crystal structure modifier is one or both of sodium citrate and potassium sodium tartrate.
5. 5. The method for preparing the high-salinity wastewater medicament according to any one of claims 1 to 4, which is characterized by comprising the following steps: and mixing the calcium-containing compound, the aluminum source compound and the crystallization structure regulator to obtain the high-salt wastewater medicament.
6. 6. The use of the high-salt wastewater medicament according to any one of claims 1 to 4 for treating high-salt wastewater with chloride ion concentration of 5 to 25 g/L.
7. 7. A method for treating high-salt wastewater by using the high-salt wastewater medicament according to any one of claims 1-4, which is characterized in that the high-salt wastewater medicament is mixed with the high-salt wastewater, reacted for 60-120 min under the condition of 20-45℃, pH-11, and subjected to solid-liquid separation after standing.
8. 8. The method of claim 7, wherein the molar ratio of aluminum element in the high-salt wastewater medicament to chloride ion in the high-salt wastewater is 1:1-3.5:1.

Description

High-salt wastewater medicament and preparation method and application thereof Technical Field The invention relates to the technical field of wastewater treatment, in particular to a high-salt wastewater medicament, a preparation method and application thereof. Background In the production process of chemical industry, pharmacy, printing and dyeing industry, coal chemical industry and other industries, high-salt wastewater containing a large amount of chloride ions can be generated. If the wastewater is directly discharged, serious harm can be caused to water body environment, aquatic organisms and sewage treatment systems, such as pipeline equipment corrosion, microbial activity inhibition, soil salinization and the like. Therefore, the efficient removal of chloride ions in the high-salt wastewater is a key difficult problem for realizing wastewater recycling or standard discharge. Currently, common methods for treating high chlorine wastewater include membrane separation, evaporative crystallization, and chemical precipitation. Although the membrane method and the evaporation method have stable effects, the problems of high investment and operation cost, high energy consumption, easy scaling and the like exist, and the method is difficult to popularize generally. The "ultra-high lime aluminum process" among the chemical precipitation processes, which has demonstrated potential for use due to its relatively low cost, is precipitated by adding calcium and aluminum salts to form insoluble calcium chloroaluminate (Ca 4Al2Cl2(OH)12, freund's salt) to fix chloride ions. However, the prior art has problems of insufficient reaction efficiency, large dosage of the medicament, incomplete precipitation reaction and the like when treating wastewater with extremely high chloride ion concentration. The reason for this is that the core components and the proportion thereof cannot be systematically optimized for the water quality characteristics of high concentration chloride ions, resulting in failure to maximize the chlorine removal efficiency of the unit agent. Although the method can be improved by optimizing the molar ratio of calcium to aluminum, adding seed crystals and the like, the methods still belong to the conventional technical category, and the treatment efficiency is difficult to be greatly improved and the treatment cost is difficult to be reduced. Therefore, there is a need to develop a novel complex medicament with higher removal efficiency, better sedimentation performance and lower medicament consumption. Disclosure of Invention The invention aims to provide a high-salt wastewater medicament, a preparation method and application thereof, which obviously improve the crystallization process, precipitation form and solid-liquid separation performance of Freund's salt and solve the problems in the prior high-salt wastewater chloride ion removal technology by introducing a specific structure regulator component. In order to achieve the above object, the present invention provides the following technical solutions: According to one of the technical schemes, the high-salt wastewater medicament is composed of a calcium-containing compound, an aluminum source compound and a crystallization structure regulator, wherein the molar ratio of calcium element to aluminum element in the calcium-containing compound to the aluminum source compound is 2:1-4:1, and the mass of the crystallization structure regulator is 10-30% of the total mass of the high-salt wastewater medicament. The second technical scheme of the invention provides a preparation method of the high-salinity wastewater medicament, which comprises the following steps: and mixing the calcium-containing compound, the aluminum source compound and the crystallization structure regulator to obtain the high-salt wastewater medicament. The third technical scheme of the invention provides application of the high-salt wastewater medicament in treating high-salt wastewater with chloride ion concentration of 5-25 g/L. According to the fourth technical scheme, the method for treating the high-salt wastewater by the high-salt wastewater medicament is provided, the high-salt wastewater medicament and the high-salt wastewater are mixed, reacted for 60-120 min under the condition of 20-45℃, pH-11, and solid-liquid separation is carried out after standing. Compared with the prior art, the invention has the following beneficial effects: 1. The method has the advantages of strong pertinence and high efficiency, is particularly suitable for high-concentration chloride ion wastewater of 5-25 g/L by optimizing the proportion of calcium and aluminum components, and can realize efficient and stable removal in a wider concentration range. 2. The preparation has low cost, the raw materials are common industrial products, the sources are wide, the price is low, the preparation process does not need complex technology, and the treatment cost is greatly reduced. 3. The process has