Special Adsorption Process for Treating Fluorine-Containing Wastewater in the Glass Industry

The glass industry is an important industry in China and plays a crucial role in the country's economic development. During the "Tenth Five Year Plan" period, China's fixed assets investment grew rapidly, industrialization and urbanization accelerated, and the demand for construction glass, automotive glass, and glass products increased significantly. It has created great space for the development of the glass industry, and China's glass manufacturing capacity has jumped to the top in the world for more than ten years. During the deep processing and production of glass, some wastewater is generated, mainly concentrated in pre-treatment processes such as edge grinding, drilling, and cleaning, as well as a small amount of cooling circulating water. The main substances in glass wastewater are fluorine and heavy metals.

Sources and hazards of wastewater in the glass industry

The water consumption in the glass deep processing industry is mainly in the pre-treatment process, including edge grinding, drilling cooling water, and washing water. The wastewater generated by the pretreatment process contains a large amount of glass silica powder, as well as a small amount of silica powder, diamond grit, cutting kerosene, cleaning agents, and citric acid. This type of wastewater has the characteristics of large water volume, high concentration of glass powder, and difficult biochemical degradation. In addition, there are some additives and oils in the water, and most of the wastewater is acidic.

These wastewater have relatively light pollution compared to the chemical industry, but due to their large discharge volume and the presence of pollutants such as oil, SS, fluorine, and heavy metals in the discharged wastewater, these pollutants pose a serious threat to the natural environment and human health. For example, untreated fluorine-containing wastewater can enter the ecological environment, infiltrate into the soil, accumulate fluoride ions continuously, cause groundwater pollution, and then return to the human body through a series of ways, causing major diseases due to absorption by the human body. So, the wastewater from glass factories must be treated before discharge.

Common treatment methods for fluorine-containing wastewater in the glass industry

Chemical precipitation method

Chemical precipitation is the most commonly used method for treating fluorine-containing wastewater. It mainly involves adding a precipitant to the wastewater to convert fluoride ions into insoluble precipitates or form co precipitates through complexation. The solid-liquid separation process is used to remove fluoride ions.

Coagulation sedimentation method

The coagulation precipitation method refers to the addition of substances with coagulation ability or chemical reaction with fluoride ions, such as aluminum salts, iron salts, and other coagulants, to high concentration fluorine-containing water. The principle is that coagulants form a large number of positively charged colloidal particles in water, which adsorb negatively charged fluoride ions in the water. This method has the advantages of high efficiency, simple operation, and low power consumption, but it takes up a large area and the uncertainty of the dosage of chemicals, which can easily lead to secondary pollution of the water body.

Electrochemical method

Electrochemical fluoride removal can be divided into two categories: electrocoagulation and electrodialysis. Electrocoagulation is an electrolytic method in which an aluminum or iron electrode serves as the anode. Under the action of a direct current electric field on the surface, it hydrolyzes into different forms of hydroxides with coagulation properties, adsorbing fluoride ions and fluoride complexes in water to remove fluoride ions.

Haipu Technology - Special Adsorption Process for Treating Fluorine Containing Wastewater

In response to the common problems of introducing new ions and incomplete treatment in traditional processes, Haipu Company has independently developed a series of high-performance special adsorption materials. Through techniques such as imprinting pore making, the pore size of porous materials can be accurately adjusted. Through chemical modification, the selectivity of materials can be increased, and the anti pollution performance of materials can be enhanced. At present, this process has been scaled up in industry and successfully applied to the treatment of fluorine-containing wastewater in multiple glass industries.

Case study of fluorine-containing wastewater treatment in a certain glass industry: