Flocculants generally have inorganic flocculants and organic flocculants. How to choose flocculants in wastewater treatment should be selected according to the characteristics of wastewater in specific industries. At the same time, it depends on which link the flocculant is added and what purpose it is used for.
Generally, when choosing inorganic flocculants, the composition and PH of the wastewater should be considered, and then the most suitable one (iron salt, aluminum salt or iron-aluminum salt, silicon-aluminum salt, silicon-iron salt, etc.) should be selected.
When choosing organic flocculants (such as polyacrylamide PAM), it mainly depends on whether anionic polyacrylamide, cationic polyacrylamide or nonionic polyacrylamide are used. Anionic polyacrylamide is generally divided into weak yin, medium yin, and strong yin depending on the degree of hydrolysis.
The selection of cations is generally used in sludge dewatering. The selection of cationic polyacrylamide is very important. Medium and strong cationic polyacrylamide is generally used in urban sewage treatment plants. Weak cations are generally selected for sludge dewatering in papermaking and printing plants, and strong cations are generally selected for pharmaceutical wastewater. And so on.
Each kind of wastewater has its own unique characteristics. Nonionic polyacrylamide is mainly used under weakly acidic conditions, and more nonionic PAM is used in printing and dyeing plants.
Polymersco reminds us that the selection of all these flocculants can only be determined based on the test. In the test, the approximate dosage is first determined, the flocculation and precipitation rate are observed, the treatment cost is calculated, and the economical and applicable flocculant is selected.
