Magnesium hydroxide as an alkali has a unique buffer and neutralization capacity, in the use of the process of pH value will not exceed 9, the neutralization process is gentle, the precipitation grain is large, the sedimentation speed is fast, the silt is easy to filter and discharge, thus reducing the volume of silt, reduce the processing cost. And it has strong adsorption capacity, high activity and low corrosion. These advantages make magnesium hydroxide in such as papermaking, printing and dyeing, leather, electroplating, urban sewage and fluoride containing acid wastewater treatment can be widely used, as a professional magnesium hydroxide manufacturers, the following will introduceMagnesium hydroxideApplication in sewage treatment.
1, acidic heavy metal wastewater treatment Mg (OH), due to the great specific surface area, in the treatment of acid-containing heavy metal wastewater, the effect is much better than the general magnesium hydroxide effect, 5min basically completed, the adsorption capacity reached 102 mg/g. At the same time, the recovered magnesium hydroxide can be used for the treatment of acid-containing heavy metal wastewater many times after roasting, and the utilization rate of raw materials can be improved in the actual wastewater treatment, which is in line with the idea of sustainable development in industry. The treatment effect of magnesium hydroxide method in treating acidic waste liquid is obviously better than that of limestone method. Although the unit price of magnesium hydroxide is higher than that of limestone, due to its light weight, strong adsorption capacity and large activity, the dosage of treatment agents is reduced and the operation cost is reduced by more than 25%. In addition, magnesium hydroxide as alkali has unique buffering and neutralizing ability, the pH value will not exceed 9 at the highest during use, and the neutralization process is gentle, the precipitated grains are large, the sedimentation speed is fast, and the silt is easy to filter and discharge, thus reducing the volume of silt sediment and reducing the processing cost; secondly, magnesium hydroxide has low corrosion resistance and has great advantages in equipment investment and maintenance.
2. Printing and dyeing wastewater Printing and dyeing wastewater is a kind of industrial wastewater with great harm to the environment. Its discharge is large, its composition is complex, and its color is deep, especially for various dyes with good water solubility and strong coloring power. It is difficult to use traditional treatment methods. Magnesium hydroxide is used to treat printing and dyeing wastewater. Dye wastewater is decolorized by adsorbing negatively charged anionic dyes with "F charge № IV". Its saturated adsorption capacity for direct gray dyes is 2.122 g/g,. The saturated adsorption capacity of direct red dye is as high as 2.045 g/g, and it has a good decolorization effect on dozens of dyes. 3. Magnesium hydroxide treatment of phosphate in domestic sewage and wastewater will promote the growth of algae and lead to hypoxia of fish. Ammonium will endanger the survival of marine organisms. The excessive discharge of phosphorus and ammonium has caused the major lakes and oceans in China to face serious eutrophication and red tides. The effect of magnesium hydroxide dephosphorization and ammonium removal is remarkable. Adding magnesium hydroxide to wastewater containing phosphate and ammonium according to a certain proportion can precipitate magnesium ammonia phosphate, so as to achieve the purpose of removal. Under the condition of pH ≤ 10.5, the removal rates of ammonia and phosphorus are 82% and 97%, respectively. The generated precipitate can also be used as fertilizer after filtration and separation.