Granule(powder) coal based fuel and preparation method thereof

Abstract

The invention discloses a grain(powder)-shaped coal-based fuel and the process for preparation, the coal-based fuel is prepared through adopting a wet fine grinding-dry rough grinding technique, namely the process for preparation comprises the following steps: mixing raw material coal and liquid whose mass ratio is (7-8):(2-3), and preparing into slurries with slurries through wet fine grinding, wherein the dosage of dispersing agent is 0.3-3% of the amount of dry coal in raw material coal, and the concentration of slurries is 70%-80%, coal particle content which is less than 74um in slurries is bigger than 90%, utilizing dry rough grinding to grind raw material coal and dispersing agent into dry coal powder, wherein dispersing agent is 0.3-3% of dry coal amount in raw material coal, coal particle content which is less than 74um in dry coal power is less than 50%, stirring the above slurries and the above dry coal powder according to 100:(30-80), controlling coal particles stacking efficiency in 60%-80%, shaping grain(powder)-shaped coal-based fuel, wherein maximum particle grain size is 300um, the content of coal particles which are less than 74um are bigger than 75%, and the content of coal is bigger 80%.

Description

technical field [0001] The invention relates to the harmless treatment of clean coal-based fuel and high-concentration organic waste liquid, in particular to granular (powder) coal-based fuel. High-concentration organic waste liquid refers to industrial waste water containing more than 1% organic harmful substances, or waste water whose COD exceeds 2000 mg / L. Background technique [0002] Coal-based fuels mainly include raw coal and coal-water slurry. Raw coal has large particle size, low combustion efficiency and serious pollution. As a clean fluid coal-based fuel, coal-water slurry has high combustion efficiency and low pollutant emissions, and can replace oil and coal for combustion. At present, it has been widely used in industrial kilns, boilers, ceramics and fertilizer industries. Coal-water slurry is a fluid coal-based fuel, which requires special storage and transportation equipment during transportation, and the storage and transportation costs are high. Since th...

AI Technical Summary

Problems solved by technology

The existing problems are: (1) when the wet grinding pulp is prepared, the sulfur-fixing agent is added together for grinding. Since the sulfur-fixing agent is a calcium-based sulfur-fixing agent, this type of sulfur-fixing agent has a great influence on the rheology of the coal-water slurry Large, can significantly increase the viscosity of coal water slurry, which is not conducive to flow

(2) There is no dispersant in the ground dry coal powder, because it is difficult to mix the wet-prepared coal-water slurry with dry coal powder evenly, so the dispersion of the dispersant in the solid-state coal-water slurry is uneven, resulting in partial solid When the coal water slurry is restored to slurry, there is insufficient amount of dispersant, which makes slurry difficult and affects the use of users

(3) The particle size distribution and corresponding stacking efficiency of the coal particles in the wet refining and dry coal powder are not controlled in the preparation process of this solid coal water slurry, but the particle size distribution range of the solid coal water slurry is pointed out. Therefore, It is difficult to ensure that CWS with excellent rheological properties can be obtained when returning to slurry

[0004] Chinese patent CN101029260 discloses a preparation method of instant coal-water slurry. The essence of the preparation method is to grind coal, additives and liquid in a certain proportion, but for coal with a water content of about 10-20%, dry grinding mine, its grinding efficiency is very low

[0005] In addition, my country's paper industry, printing and dyeing industry, brewing industry and some chemical industries will produce a large amount of organic high-concentration waste liquid, and the cost of purification of such waste liquid is extremely high