Effect of dispersant on properties of coal slime water slurry

The study is made with 2 kinds of slurry prepared with coal slime of different properties using respectively low-cost modified lignin and high-cost naphthalene sulfonate as dispersant. Then an analysis is made of the effect of dispersant on the rheological property, fixed-viscosity concentration, flowability and stability of each kind of slurry. Study result shows that the two dispersants vary in influence. With the use of naphthalene sulfonate as dispersant, the slurry prepared exhibits a better dispersion and much lower viscosity yet a relatively poor stability, while the use of modified lignin as dispersant can yield a quite contrary result—less satisfactory dispersion, better stability yet higher viscosity. It is observed that when both kinds of slurry are prepared with the use of the 2 dispersants in combination, neither slurry shows necessarily a noticeable increase in fixed-viscosity concentrate yet the fluidity and stability of both slurry are significantly improved. The use of the mixed dispersant is high in performance-cost ratio. In the future, it is considered to have the lignin modified after it first undergoes purification and have the two dispersants mixed in different proportions. Work will also be made on the use of the dispersants in combination with other additives and the development of highly adaptable additives.