Finishing agent for coal washing water

Abstract

A treating agent for the coal-washing water is proportionally prepared from polyacrylamide and at least one of magnesium chloride, magnesium sulfate, sodium chloride, calcium chloride and calcium oxide through mixing and stirring.

Description

technical field [0001] The invention relates to a coal washing water treatment agent, in particular to the composition of a coal washing water treatment agent. Background technique [0002] The coal washing water after coal preparation contains a large amount of suspended solids. The suspended solids are extremely fine coal powder, mineral powder and other particles. The coal washing water needs to be treated to separate the suspended solids before it can meet the discharge standard or be recycled. The suspended solids in coal washing water are very fine particles, which are difficult to settle down. When treating coal washing water, it is necessary to add a treatment agent to the coal washing water to make the fine particles flocculate and settle down, so that the suspended solids can be separated. Among the treatment agents, polyacrylamide products are high-efficiency coal washing water treatment agents. When treating coal washing water, polyacrylamide products should be u...

AI Technical Summary

Problems solved by technology

In the coal washing water treatment agent used in combination with polyacrylamide and magnesium chloride, magnesium chloride is a water-soluble inorganic salt that dissolves quickly in the water in the dissolution tank, and polyacrylamide is a water-soluble polymer Compounds, polymers have a large molecular weight, and the molecules are accumulated in the structure of random coils. When polyacrylamide is dissolved in water, the molecular clusters of the random coil structure swell first, and then the polyacrylamide molecules can be recovered from the swelling. The final molecular clusters gradually diffuse into the water to form a polyacrylamide aqueous solution. The dissolution rate of polyacrylamide in the water in the dissolution tank is very slow. In addition, the dissolution rate of polyacrylamide in water is related to the fineness of polyacrylamide Larger, the smaller the particle size of polyacrylamide, the faster the dissolution rate in water. For example, the dissolution rate of polyacrylamide in water with a fineness of 40-100 mesh is much faster than that of polyacrylamide with a fineness of about 10 mesh. However, when the particles of polyacrylamide are too fine, the fine polyacrylamide particles will gather into groups due to the effect of surface tension after being put into water, and the surface of the gathered polyacrylamide groups will be wet, forming a sticky closed shell. The dry powder in the middle of the group cannot touch water, and it is more difficult to dissolve in water, so the particles of polyacrylamide used as a water treatment agent in the prior art are not very small, although the particles will not be aggregated into groups due to the effect of surface tension when placed in water , but the larger particles also make the dissolution rate of polyacrylamide in water slower, especially the polyacrylamide particles with larger particles are all wetted and swollen polyacrylamide particles will also gather together to become larger, viscous The swelling group of polyacrylamide particles makes it difficult for the polyacrylamide molecules of random coils to diffuse out of the swelling group and dissolve in water to become an aqueous solution of polyacrylamide

In order to prepare polyacrylamide aqueous solution in coal washing water treatment, relatively large polyacrylamide dissolving equipment is required. If polyacrylamide is not dissolved well, the swollen polyacrylamide will be lost with coal washing water, which will not only make expensive polyacrylamide Wasted in vain, the viscous colloidal polyacrylamide after swelling also makes it difficult to filter the separated coal slime suspension; moreover, polyacrylamide particles are easy to absorb moisture in the air, and the moisture-absorbing polyacrylamide flows The performance is not good, which affects the addition metering in production. In order to keep the polyacrylamide particles dry, there must be equipment for applying dry air to the polyacrylamide particles.

In order to fully dissolve polyacrylamide and keep polyacrylamide particles dry, the investment in coal washing water treatment equipment is relatively large.