After the coagulant is put into the water, the proper hydraulic conditions need to be created to successfully complete the coagulation action. The whole coagulation process is divided into two stages, one stage is called mixing; the second stage is called flocculation. These two stages have different requirements for water turbulence. The mixing stage generally does not exceed 2 minutes, so after the coagulant is put into use, the water must be vigorously stirred, so that the flocculant can be quickly mixed with the water, resulting in a hydrolytic shrinkage reaction. The flocculation stage requires proper turbulence in the water flow to further collide and aggregate the flocculants,* eventually forming larger flocculants. However, the turbulence in the flocculation stage should be weakened to avoid the flocculant breaking under long-term high-intensity mixing.

If the inorganic coagulant is combined with polyacrylamide PAM, the inorganic coagulant is easily neutralized by static electricity, because the PAM has a weak ability to collect the micropolymer flocculant alone. When a polymer with a certain particle size is formed, PAM can fully play the role of bridge. The flocculants are electrically neutralized, bringing the flocculants close to each other, forming large and dense flocculants. At this time, polyacrylamide is a coagulant, so polyacrylamide also becomes a coagulant. Polyacrylamide (PAM) is a polymeric flocculant that produces stable flocculants by bridging adsorption. That is, the small and uniform particles and clay particles in the dispersed phase are adsorbed by the active functional groups on the carbon chain of PAM to form flocculation and connect with each other to form a coarse flocculant. High flocculation strength, less interstitial water, compact flocculation structure, easy to settle.

When a coagulant is used in combination with a polymer flocculant (coagulant aid PAM), iron salts and aluminum salts are usually added first to make suspended solids or colloidal particles produce micropolymers at intervals of no more than 1 minute, and then PAM is added to produce more Great flocculant. This can not only save the amount of coagulant, but also improve the coagulation effect.

Shandong Welldone, as one of the top ten manufacturers of polyacrylamide in China, can provide customers with the required anionic, cationic and non-ionic polyacrylamide. If you are interested in a certain product, don’t be hesitate to contact us.