The “three wastes” produced in coal washing operation mainly refer to coal slime, coal gangue and coal washing wastewater (coal slime water), among which coal washing wastewater is the most serious harm to the environment and the most difficult to dispose. However, due to the huge water consumption of coal washing and the coal slime water generated after coal washing contains a variety of pollution substances, if the effective scientific disposal can not be directly discharged, it will cause a large amount of water waste, but also pollute the surface water and groundwater. In addition, when the coal washing wastewater is discharged into the natural water body, the suspended particles contained in it will make the natural water body turbid, significantly reduce the transmittivity, inhibit the photosynthesis of algae and other aquatic plants in the water body, slow down their growth rate, and then lead to the decrease of the oxygen concentration in the water body, weaken the self-purification ability of the water body, and lead to the death of a large number of aquatic organisms in the long run. Have a serious negative impact on the environment.
PAM is a polyacrylamide used in coal washing wastewater and coal slime wastewater. It is a linear polymer, harmless, non-corrosive, and soluble in water. When aqueous solution is mixed with slime water, the active group on the polyacrylamide molecular chain will adsorb the surface of fine particles in slime water, so as to connect the particles to form a larger flocculent, and accelerate the sedimentation rate of slime water.
For the treatment of slime water, it is necessary to add appropriate amount to effectively exert its flocculation effect. Measurements can be made on the basis of selected slime water. Because there are many specifications and technical indicators of sewage treatment agent, it is necessary to carry out small-scale test and final test on the product when the technical parameters of the product are not clear. There is no need to conduct final test for products that fail the minor test. Products that pass the mini-test also need to pass the final test to check the actual performance.
