水质硬度对煤泥浮选的影响

Effect of water hardness on coal flotation

用循环水和自来水作为浮选试验用水,用石膏和硫酸钾作为水质调整剂,通过实验室和工业试验,研究水质硬度对煤泥浮选的影响.结果表明:水质硬度是影响煤和黏土颗粒之间分散稳定性的关键因素.随着水质硬度的升高,浮选精煤灰分提高了1%~2%,但精煤产率没有明显变化.水质硬度小于35°DH时,水质硬度越高,煤和黏土颗粒之间的凝聚作用越强,精煤灰分越高;水质硬度大于35°DH时,这种凝聚作用不再增强,精煤灰分也不再提高.

Laboratory experiments and industrial scale tests were designed to study the effect of water hardness on coal flotation in recycling water and tap water. The gypsum and potassium sulphate were used as modifying agents to adjust the water quality. The results show that the water hardness is a key factor that influences the dispersion stability between coal and clay par- ticles. The ash content of flotation clean coal was increased by 1 ^--2 ~ with the increasing of water hardness, and there is no obvious change for the yield of flotation clean coal. At the wa- ter hardness below 35 ~DH, the coagulation between coal and clay particles and the ash content of flotation clean coal generally increase with the increasing of water hardness. Further increas- ing the water hardness doesfft further enhance the coagulation between clay and coal particles, and the ash content of flotation clean coal.