STUDY ON SINTERING PHENOMENA OF COAL ASH DURING BURNING URANIFERROUS COAL——I. SINTERING ACTION OF COAL ASH AND RESULTANT LOCK-UP OF URANIUM

In the range of 400- 1100℃ the combustion tests are carried out with three kinds of uraniferrous coal samples taken from different regions in China. The apparent densities and uranium extractions of ash products are determined. It has been proved that the ash products are sintered during burning; and the sintering process is in accordance with the formula of the Complex Sintering Action.During the sintering of ash the uranium is lock-up therein. As combustion temperature is increased, the sintering degree of ash is increased and more uranium is locked up, so that uranium extraction from ash obtained at higher ashing temperature is decreased. It has been found that the experimental formula between apparent density d which represents the sintering degree and uranium extraction 77 is as follows.For sample A,For sample B,For sample C,