What is the amount of dispersant to add to the gasification ash water?
Thread Content
How is the amount of dispersant added to the gasification ash water determined?
It is determined based on the system’s graywater circulation rate; generally, it ranges from 50 to 100 ppm. If the quality of the water used in production is good, the ash content of the raw materials is low, and the dispersant chosen is appropriate, then 50 ppm should be sufficient. Otherwise, a level of 100 or even 120 ppm may be required.
The dosage of ash water dispersant is calculated based on the circulation volume, with a dosage concentration generally ranging from 60 to 100 ppm; the specific concentration depends on the quality of the ash water as well as the ash content in the coal used for gasification. Currently, the concentration of dispersant in the ash water system for water-coal slurry gasification can be kept below 80 ppm. In contrast, coal used for gasification in powder-coal gasification systems generally has a higher ash content, so the concentration of dispersant used can be increased appropriately; it is recommended to use a concentration of 80–100 ppm.