Polyacrylamide PAM selection should focus on the following aspects: Generally speaking, anionic products and non-ionic products for alkaline, neutral or weak acid, the main material for the inorganic sludge, and the higher the solid content. The greater the amount of flocculant used. The molecular weight of the flocculant is chosen according to the floc size required for the process. The flocculant must be mixed and dissolved with the sludge before treatment. ) Can improve the floc strength by increasing the molecular weight of the flocculant. The degree of hydrolysis of the flocculant must be screened by experiment. The choice of flocculant must take full account of the requirements of the process and equipment.
Sludge dewatering agents are generally cationic polyacrylamide. Urban sewage treatment of urban sewage is usually used biological and physical law into the line, in which the biological method is widely used because of the high efficiency. Polyacrylamide PAM flocculants can be used in all stages of municipal wastewater treatment. Such as primary sedimentation treatment, secondary sedimentation treatment and concentration, the most widely used sludge dewatering stage. Add flocculants to increase the rate of sludge treatment. Reduce the water content of the sludge cake. Reduce the sludge volume and so on. The formation of floc filter good advantages. Anionic polyacrylamide is commonly used in the following wastewater treatment process: wastewater pretreatment, post-treatment, including pretreatment, including adsorption filtration, etc. According to the different nature of the sewage can be used oxidation, biological treatment, air float and so on. Due to the wide range of industrial effluents, the pollutants contained therein are very complex. The nature of the sewage varies greatly. Therefore, the selection and use of specific industrial wastewater treatment must be determined by a large number of laboratory tests and field tests. Polyacrylamide must be dissolved at a low temperature, a certain temperature and then add a row, the type of product and dosage should be based on water quality and water purification technology characteristics. By experiment. Polyacrylamide PAM adsorption bridge with strong ability, with multiple functional groups, flocculation effect is good, wide application range, less dosage, resulting in less sludge.
Sometimes according to the actual production situation, two or three flocculants in combination. The effect of anionic polyacrylamide flocculant is affected by many factors such as PH value of sewage, content of suspended solids, temperature and so on. The current flocculant unsafe and secondary pollution more and more attracted the attention of society. Polyacrylamide itself is not toxic. But some products which do not respond to the residual monomer toxicity is great. Therefore, the product used for drinking water treatment in its water content is strict, the current product residual monomer content requirements below 0.05. Water treatment processes include enrichment, sedimentation, flotation and filtration. In most cases it is required to add a coagulant before adding flocculant. Thereby producing a large volume of floc to increase the rate of solid-liquid separation. Industrial water in the case of low demand only need to concentrate and sedimentation.