SU1247070A1 - Method of preparing water and coal suspension for conveying along pipeline - Google Patents

Description

The invention relates to magistrade hydraulic transport of coal suspensions through a pipeline and can be used in the processes of preparation of highly concentrated and finely dispersed suspensions.

The purpose of the invention is to intensify the process of preparing the suspension and reducing the air content in it.

FIG. 1 is a diagram of an industrial implementation of a method for preparing a water-coal slurry; in fig. 2 - laboratory layout for the preparation of suspensions.

The installation contains a belt conveyor 1, a ball mill 2, a dispenser 3, a mixing tank 4, a vacuum unit 5, a dispenser 6 of water. In a mixing tank 4 with a crest 5 by an air nozzle 6 and a water nozzle 7, a paddle stirrer 8 is installed.

Example. The standard coal in the belt conveyor 1 is fed to the ball mill 2 and milled to a class of 0–200 µm, from the mill coal is supplied to the metering unit 3 and from the metering unit to the mixing tank 4. The suspension is prepared from 65 wt. h. coal and 35

weight. h of water. The coal is poured into the mixing tank 4, tightly sealed, and the coal powder is degassed through the water tank.

pipe 6 to less pressure

0.025 MPa; water is fed through a water nozzle 7 and stirred by a paddle stirrer 8 for 30 seconds at 1000 rpm.

When mixing fine coal (less than 0.2 mm) with water to form a suspension of maximum concentration on coal, a 65% specific surface area of the coal particles determines the minimum amount of water to create a water film, namely, the higher the specific surface area (lower particle size), the more water is required for wetting (and therefore

lower maximum suspension concentration).

For different types of coal, the porosity of the particles is up to 25%. In order to remove air from the surface of the particles, leaving it in the pores, it is necessary to create a pressure of less than 0.025 MPa, freeing the surface of the particles to be wetted with water. If the pressure is higher, then the air is not removed from the surface and mixing is deteriorated.

FIG, g

Compiled by T. Kruglov Editor N. Slobod nickname Tehred V. Kadar Proofreader M. Demsh

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VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Projectigt, 4

Claims (3)

1. METHOD FOR PREPARING A WATER-COAL SUSPENSION FOR TRANSPORTATION BY PIPELINE, including dry grinding of coal, fractionation of coal, loading of coal into a mixing tank, adding water and mixing coal with water, characterized in that, in order to intensify the process of preparing the suspension and reduce the air content in it, the mixing tank with coal powder is evacuated before adding water and during the entire mixing process, while the pressure in the mixing tank is maintained it is 0.025 MPa. 2. The method according to p. 1, characterized in that the particle size is adjusted to a size of less than 0.2 mm 3. The method of pop. 1, characterized in that the water is taken in an amount of 25-50% by weight of the suspension. > SU ,, „1247070