How to Choose Mine Water Treatment Technology

I. Current situation of industry and characteristics of mine water and sewage

Coal is an important basic energy and raw material in our country and plays an important strategic role in the national economy. In the primary energy structure of our country, coal accounts for more than 70%. Since the founding of the People's Republic of China 57 years ago, the total production of coal has exceeded 372 x 108 tons, which has made great contributions to the national economic and social development of our country. In the process of coal mining, a large number of mine water and water resources will inevitably be discharged and destroyed. At present, the amount of mine water discharged in China is about 4.2 billion m3, accounting for 80% of the whole mining industry (non-ferrous metallurgy, gold, chemical industry and other mines), while the utilization rate is about 26%. Most of the coal-rich areas in China are water-poor areas. Ten of the 13 coal bases with over 100 million tons planned for the 11th Five-Year Plan are water-deficient areas. The water shortage in these mining areas is very serious, and many coal mines are very short of water for production, even using unqualified water for production. The shortage of water resources has seriously restricted the economic development of these mining areas and the improvement of people's living standards.

Water Quality Characteristics of 1.1 Ferromanganese Mine Water

Coal mine water containing iron and manganese is mainly formed by infiltration of groundwater containing iron and manganese in stratum. Iron and manganese in mine water exist in the form of divalent iron or divalent manganese. Because of the influence of coal mining process, mine water containing iron and manganese in coal mine has different characteristics from groundwater containing iron and manganese.

2. Water quality characteristics of high turbidity mine water

(1) Coal mine water with high turbidity has high suspended matter content and poor sensory properties.

(2) The suspended solids in mine water with high turbidity have small particle size, light specific gravity and slow settling speed.

(3) It is difficult to form alum in coagulation process of mine water with high turbidity, and the settlement effect is poor.

3. Water quality characteristics of mine water with high salinity

Mine water with high salinity is the result of the contact between groundwater and carbonate and sulfuric acid strata in coal measure strata, which are dissolved in water. Ca 2+, Mg 2+, HCO 3-, CO32-, SO42-in mine water are increased, and some acid mine water and carbonate rock strata are neutralized, resulting in higher salinity. In some mining areas, the climate is dry, the annual evaporation is much larger than precipitation, the salinity of stratum is higher, the salinity of groundwater increases accordingly, and a few mining areas are in the mixed distribution area of seawater and mine water, so the salinity of mine water increases.