Settling Velocity and Particle Size distribution- Coal Combustion. 1

[jjv2006]

I am in the process of designing a temporary wastewater sedimentation basin (settling tank) for a coal fired power plant. I am trying to get more information of particle size and settling velocity for coal combustion by-products. The data available based on literature review almost always suggests that it is dependant on the type of coal and the efficiency of the combustion process. Also, I was able to glean some data suggesting that particle size is less than 10 µ m with a varying range from 0 to 15 µm. Can anyone direct me on information regarding settling velocity information and their variation for various seasons (summer and winter) for Coal Combustion by-products, particularly coal ash and fly ash?. Any particular column tests for the same processes will also be of help to me.

Thanks in advance.

 

[davefitz]

The size willalao be a function of what part of the combutsion process it is extracted.

Furnace bottom ash can be much larger, up to 1 ft dia clinkers. This is 15-20% by weight of the ash

economizer hopper ash can be 100+ um in dia, with some popcorn ash up to 1/4" dia

precipitator ash is all other ash that has escaped the coarse separation of the economizer exit turns, use Stokes flow to roughly determine the max cut size or particle diameter to excape the 90 degree turn at the econ outlet, gas velocity about 50-75 fps.