Polyacrylamide (PAM) and its application in water treatment
Water pollution control and governance is an important part of environmental protection and disposal of waste water treatment get pay more and more attention.
Polyacrylamide (PAM), a linear water soluble polymer, is a very important role in the field of water treatment due to the high molecular weight, water-soluble, regulation of molecular weight and various functional modification.
PAM and its derivatives can be used as effective flocculants, thickening agent, drag reduction agent, widely used in water processing, paper making, petroleum, coal, geology, construction and other industrial sectors.
In groundwater, surface water and sewage, impurities and pollutants usually exist as many particles which is too tiny to settle under gravity. Because natural sedimentation has been unable to meet the requirements, with the aid of chemicals accelerate the settlement of technology has been applied in production. For example, PAM molecule absorbs on several particles and make bigger floc, therefore, settlement of particles are accelerated.
Compared with the inorganic flocculant, PAM has severals important advantages: many varietions for various conditions, high efficiency, less dosage, less sludge generated, easy post-treatment. This makes it the most ideal flocculant.
It is about the dosage of inorganic coagulant 1/30 to 1/200.
PAM is sold in two main forms: powder and emulsion.
The powder PAM is easy to transport, but not easy to use (dissolvation devices is needed), while the emulsion is not easy to transport and has shorter storage life.
PAM has big solubility in water, but dissolves very slowly. Dissolvation costs several hours or overnight. Good mechanical mixing will help dissolve the PAM. Always slowly add PAM to stirred water - not water to PAM.
Heating can slightly increase the dissolution rate, but the temperature should not exceed 60°C.
The highest PAM concentration of the polymer solution is 0.5%, the concentration of low molecular PAM can be configured into 1% or a little higher.
Prepared PAM solution must be used in several days, otherwise the performance of flocculation will be affected.
Post time: Jun-03-2022