Polyacrylamide flocculants for water soluble polymer, insoluble in most organic solvents, has good flocculation sex, can reduce the friction resistance between liquid, by ion characteristic points can be divided into non-ionic and anionic, cationic and amphoteric four types.Polyacrylamide flocculant is widely applied in thickening, stable colloid, drag reduction, binding, film, biomedical materials and so on.In water treatment as a coagulant aid, flocculants and sludge dehydrating agent.Water as a drop in oil drilling, oil displacement agent.As retention aid in papermaking process, reinforcing agent.
Polyacrylamide flocculant is widely applied in thickening, stable colloid, drag reduction, binding, film, biomedical materials and so on.In water treatment as a coagulant aid, flocculants and sludge dehydrating agent.Water as a drop in oil drilling, oil displacement agent.As retention aid in papermaking process, reinforcing agent.
Polyacrylamide flocculant in wastewater treatment in the flocculation effect is due to its two characteristics: the molecular structure of the long chain (line) and polyacrylamide molecule contains a large number of active group.Polyacrylamide is straight chain polymer, because each molecule is made up of hundreds of thousands more monomer polymerization, molecular chain is quite long.If it is completely straight and its length than the average molecules (such as sugar cane), or ions such as ca2 + long more than tens of thousands of times.Because of its long, thin, bends or curled into irregular shape of the curve.This long molecular chains to outside out of many chemical reactive group: amide group conh2 and carboxyl - ˉ coo.Amide is ionic groups, but also good at vice valence bond formation and reactive adsorption and link up with other substances.Because of polyacrylamide molecular long, thin and there are many chemical reactive group, they can generate a lot of connection and precipitation particles to form a larger flocculate, the floc structure is like cotton, loose, amorphous, link each other but not very stable, inside there are a lot of space and a lot of fine network, containing a large amount of liquid, and the proportion of floc is quite close to it the existing liquid itself.Flocculate and network in all kinds of particles, this will be a variety of different components, different nature, different sizes of particles collection together.Therefore, a good flocculating agent to deal with the original particles in solution can be completely network, make the solution seems to be especially clear and transparent and luster.As a result of the floc size is larger, sedimentation and filtration is fast.Polyacrylamide flocculant in waste water and flocculation of colloid is by chemical adsorption and physical network these two forms.According to the mechanism, the high molecular weight, molecular polyacrylamide, can absorb more particles, strong ability to form a network, so the flocculation efficiency is better.Similarly, the proportion of polyacrylamide molecule carboxyl appropriate is also very important, because in the wastewater most negatively charged colloid, polyacrylamide requires just the right amount of carboxyl by calcium ion bridge and its effect.But if the carboxyl content too much, polyacrylamide molecule itself too negatively charged, molecular repulsive force between the phase itself is too big, also does not favor the flocculation effect.Polyacrylamide (PAM) is divided into the kinds of anionic, cationic, nonionic and amphoteric ionic, in wastewater treatment, polyacrylamide flocculant used to improve water treatment in the process of subsidence, clarification, filtration, the efficiency of the centrifugal process etc.
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