Coal, as known as the food of industry, has an indispensable role in the development of the national economy. Affected by the development of new energy technology and economic development and policy, in recent years, the growth of consumption of coal as an energy source has slowed down, but production and consumption are still at a historical high, and production and sales are still very huge.
Coal carbon whether in the production or use process, will produce a mixture of water and fine coal dust, such as coal industry coal washing wastewater, coal preparation plant slurry water, coal-fired power plant flushing wastewater, etc., and these coal washing wastewater mixtures are mainly characterized by the following:
1. high turbidity, fine particle size of solids, solid particles more negatively charged on the surface, due to the repulsive force of the same sex charge asked as well as by gravity and Brownian motion, so that these particles in the water to maintain the state of dispersion;.
2. Due to the interaction between the interface of solid particles in the coal slurry water (such as adsorption, dissolution, synthesis, etc.), so that the nature of the coal washing wastewater is quite complex, not only with the nature of the suspension, but also with the nature of the colloid.
3. The sludge resistance is large, the filtration water is poor, and the pressure filtration dewatering is difficult.
Therefore, the coal wastewater is particularly stable, standing for several months will not naturally settle, it is difficult to naturally clarify, after precipitation supernatant still with a large number of coal slurry and other suspended black liquid, and contains a variety of additives in the production and processing and heavy