超声波辅助煤泥脱水的研究

Study on ultrasonic-assisted coal slime dewatering

为了探索添加助滤剂以及超声波辅助处理后煤泥脱水效果的变化,以微细粒煤泥为研究对象,对煤泥性质进行了分析,综合考察了助滤剂用量、超声波频率、超声作用时间等因素对脱水效果的影响。试验结果表明:采用禾草沟选煤厂煤泥样品,在超声波与助滤剂共同作用下,当氣化钙用量为1600g/t,聚合氣化铝用量为1000g/t,聚丙烯酰胺用量为70g/t,超声波处理7min时,过滤脱水时间较空白试验减少45min,水分降低2个百分点;超声波的使用能有效减少脱水时间,并进一步降低滤饼的水分,但超声波处理时间过长反而降低了煤泥的脱水效果,其原因是超声波的空穴化和机械化学作用,使煤粒表面产生了新生的离子。

The ultrafine coal slime is taken as the object to explore the effects that can be obtained in de-watering of the material through addition of filter aid and ultrasonic-assisted trqatment.Analysis is made of the property of the slime and the combined influences on the effect of slime dewatering produced by such factors as dosage of filter aid,ultrasonie frequency and ultrasonic action time,among others.Results of test on dewatering of the slime of Hecaogou Coal Preparation Plant show that under the combined actions of filter aid and ultrasonic wave,and with the use of caleium chloride,polyaluminum chloride and polyacrylamide(PAM)respectively dosedat I,600g/t,1,000 g/t and 70 g/l,and a ultrasonie treatment time of 7 minutes,the moisture of the dewatered slime is two percentages lower than that of the untreated slime,and the filter dewatering time is cut by 45 minutes.It is found that ultrasonic treatment can lead to effective reduction of dew atering time and further cutdown of moisture of filter cake,But an excessively long ultrasonic treatment time has contrarily an adverse effect on the improvement of dewatering efficiency because of the presence of new ions on coal particle surface generated under the ultrasonic cavitation and mechanochemical effect.