초록 ▼

A pipeline pumpable coal-water slurry having a novel combination of coal particles and carrier water is prepared by a method wherein the particle sizes and their distribution are controlled in accordance with a particle size distribution formula which is especially beneficial for providing a novel c

A pipeline pumpable coal-water slurry having a novel combination of coal particles and carrier water is prepared by a method wherein the particle sizes and their distribution are controlled in accordance with a particle size distribution formula which is especially beneficial for providing a novel coal compact with a minimum amount of void space between particles and a maximum amount of particle surface area with an advantageous amount of colloidal sized particles present. These features combine to enhance the dispersing effects generated by electrolytes and/or dispersing agents selected and added to the coal compact and/or slurry to provide a near maximum zeta potential to the particles in the slurry and to provide low viscosity to the resulting yield pseudoplastic coal-water slurry. Brookfield viscosities obtained, e.g. 1000 cps, or less, at 60 rpm with 75 wt. % coal, dry basis, make the coal-water slurry especially advantageous for transport by pipeline over long distances. The coal-water slurry can be provided at a high coal content so that the slurry can be burned directly without need for dewatering at its destination.

대표청구항 ▼

A coal compact comprising finely divided coal particles, characterized in that said coal compact comprises finely divided coal particles having a particle size in the range of 1180 m0.05 m5 wgt. % of the particles being of colloidal size, said particles in said compact having a particle size distrib

A coal compact comprising finely divided coal particles, characterized in that said coal compact comprises finely divided coal particles having a particle size in the range of 1180 m0.05 m5 wgt. % of the particles being of colloidal size, said particles in said compact having a particle size distribution substantially in accordance with the following formula: [Figure]CPFT = cumulative weight percent, dry basis, of particles finer than a particle mDm=diameter of particle mDL = diameter of largest particle in compact, sieve size or its equivalent, being from 38 to 1180 mDS = diameter of smallest particle in compact, SEM size or its equivalent, being from 0.05 to 3 mn = numerical exponent, with n being in the range of 0.2 to 0.7, and with all diameters sized in m60 weight percent of said coal and at least about 20 weight percent of said water, said suspension has a Brookfield viscosity at 60 revolutions per minute of less than 4000 centipoise.