Efficient positive-pressure pneumatic conveying system of pebble coal

Abstract

The invention relates to an efficient positive-pressure pneumatic conveying system of pebble coal for pebble coal discharge of a medium-speed coal pulverizer in a heat-engine plant. The efficient positive-pressure pneumatic conveying system of the pebble coal comprises a pebble coal bunker of which the upper end is connected with a pebble coal outlet of the medium-speed coal pulverizer, wherein the outlet at the lower end of the pebble coal bunker is connected with a feeding device; the inlet at the front end of the feeding device is connected with a compressed air pipeline; the outlet at the rear end of the feeding device is connected with the pebble coal bunker via a transfer pipeline; and a gas outlet of the pebble coal bunker exhausts through a dust remover. According to the efficient positive-pressure pneumatic conveying system, the defects of an original negative-pressure pneumatic conveying system are solved; the entire system is low in energy consumption, small in noise, high in reliability and strong in delivery capacity, and the delivery capacity of the system can be reinforced by a loose duct. Meanwhile, the situation that a solving method is provided when the system is broken down is ensured, and a vibrating screen of the pebble coal bunker can effectively remove the material which is not suitable for pneumatic conveying, and ensures that the system is not blocked.

Description

technical field [0001] The invention relates to a high-efficiency pebble coal positive pressure pneumatic conveying system used for pebble coal discharge from a medium-speed coal mill in a thermal power plant. Background technique [0002] Medium-speed coal mills are widely used in power plant boiler units due to their low investment and good economy. The medium-speed coal mill will produce pebble coal during operation. The pebble coal mainly comes from gangue, pyrite, etc., which are dense and difficult to grind in the raw coal. When the coal mill is running, it falls below the wind ring, is sent into the pebble coal hopper by the scraper, and is discharged from the pebble coal discharge port at the lower part. . If the pebble coal is not discharged in time, it will accumulate in a large amount in the coal mill, which will easily cause the coal mill to fail and shut down. [0003] Pebble coal is mainly composed of gangue, crushed coal, stones, coal powder and other sundr...

AI Technical Summary

Problems solved by technology

[0006] 1. The negative pressure pneumatic conveying system needs a high-power Roots blower as the power source, which has high energy consumption;

[0007] 2. The air velocity at the end of the system is high, which is very easy to cause wear and tear on the pipeline and equipment, resulting in the failure of the system to work normally;

[0008] 3. Most of the screw feeders still use the screw feeder as the pebble coal feeding tool, which cannot be transported for large-size pebble coal. As the rotating part, the screw feeder is very prone to failure and wear when conveying the pebble coal;

[0009] 4. The effective dynamic pressure difference of the negative pressure system is at most one atmospheric pressure, which limits the conveying capacity of the pneumatic conveying system;

[0010] 5. The noise of the Roots blower is very loud, becoming a new noise source of the power plant

[0011] Traditional positive pressure pneumatic conveying systems generally use bin pumps or screw feeders as feeding equipment. Due to the special physical characteristics of pebble coal, it is difficult for bin pumps and screw feeders to achieve normal feeding of pebble coal.

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