Method for reducing coal water slurry gasification ash water suspended solids

Abstract

The invention provides a method for reducing coal water slurry gasification ash water suspended solids, which comprises the following steps: discharging coal water slurry gasification ash water into aclarification tank, adding a flocculant into the clarification tank, settling the suspended solids in the ash water under the action of the flocculant, and discharging the ash water in a clear liquidarea in the clarification tank into a high-density settling tank after settling; and enabling the ash water discharged into the high-density settling tank to be sequentially subjected to coagulationtreatment in a coagulation area in the high-density settling tank, secondary flocculation treatment in a flocculation area, sedimentation in a sedimentation area and sludge concentration treatment, and discharging the treated ash water into an ash water tank. The gasification ash water is treated in a mode of combining the clarification tank and the high-density settling tank, so that the contentof suspended solids in the coal water slurry gasification ash water is effectively reduced, the water quality is optimized, the scaling of pipelines in the system is delayed, the cleaning frequency ofequipment is reduced, and a guarantee is provided for high-load long-period operation of the production system.

Description

technical field [0001] The invention relates to the technical field of coal chemical industry, in particular to a method for reducing suspended matter in coal-water slurry gasification ash water. Background technique [0002] The gasified ash water produced by the gasification device is discharged into the ash water tank after being settled in the clarification tank. After being discharged from the ash water tank, most of the water is recycled as the production water of the gasification device, and a small part of the water is cooled and discharged to the sewage treatment plant for further treatment. Gray water discharge is 500m 3 / h. [0003] In the prior art, the suspended solids in the coal-water slurry gasification ash water are settled by adding flocculant to the clarifier, but the amount of flocculant used in this treatment method is relatively large. In terms of gray water circulation, the use of flocculant The amount is usually greater than or equal to 3PPm, result...

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Problems solved by technology

[0003] In the prior art, the suspended solids in the coal-water slurry gasification ash water are settled by adding flocculant to the clarifier, but the amount of flocculant used in this treatment method is relatively large. In terms of gray water circulation, the use of flocculant The amount is usually greater than or equal to 3PPm, resulting in higher costs, and the content of suspended solids in the gray water after settling in the clarifier is still high, and the products of coal combustion are the main source of suspended solids

After the above-mentioned gray water is discharged to the sewage treatment, the related equipment of the sewage treatment will be severely scaled, which will seriously affect the smooth operation of the sewage treatment

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