Phosphoric acid cleaning is a common surface treatment method, which is widely used in machinery, electronics, chemical industry and other fields. If this wastewater is discharged without treatment, it will cause serious pollution to the environment. Therefore, the treatment process of phosphoric acid cleaning wastewater is particularly important.
Phosphoric acid cleaning wastewater treatment process
Chemical precipitation method: The chemical precipitation method is to convert the heavy metal ions in the wastewater into insoluble precipitate by adding a precipitant to the wastewater, and then remove it by precipitation, filtration and other methods. Commonly used precipitants include hydroxides, sulfides, etc. The chemical precipitation method has the advantages of simple operation and high treatment efficiency, but it also has the problems of chemical consumption and secondary pollution.
Adsorption method: The adsorption method uses the adsorption of adsorbents to remove pollutants in wastewater. Commonly used adsorbents include activated carbon, zeolite, diatomaceous earth, etc. The adsorption method has the advantages of simple operation and high removal efficiency, but the regeneration and replacement cost of adsorbent is high. In phosphoric acid cleaning wastewater, adsorption can be used to remove contaminants such as heavy metal ions and phosphates.
Biological treatment method: The biological treatment method converts the organic matter in the wastewater into harmless substances or intermediate products that are easy to separate through the metabolic action of microorganisms. Biological treatment methods mainly include activated sludge method, biofilm method, anaerobic biological treatment and other methods. The biological treatment method has the advantages of low treatment cost and simple operation, but the treatment time is long and the requirements for water quality are high. In phosphoric acid cleaning wastewater, biological treatment can be used to remove contaminants such as organophosphates.
Combined process: In order to improve the treatment efficiency and treatment effect of phosphoric acid cleaning wastewater, a combination of multiple processes is often used for treatment. Common combination processes include "chemical precipitation + adsorption", "biological treatment + adsorption", "chemical precipitation + biological treatment", etc. The combined process can give full play to the advantages of various processes, improve the treatment efficiency and reduce the treatment cost. In phosphoric acid cleaning wastewater, a combined process of "chemical precipitation + activated carbon adsorption" can be used to remove heavy metal ions through chemical precipitation, and then remove pollutants such as phosphate and organic matter through activated carbon adsorption.