分散剂和PAM促进长焰煤浮选的试验研究

为合理有效地利用长焰煤中的细粒煤泥，对其进行浮选试验研究，考察了分散剂和聚丙烯酰胺PAM对其浮选的促进作用。结果表明，作为动力用煤，长焰煤精煤灰分不能太低，宜为16~20%，煤油和仲辛醇用量分别应在1000 ~ 2000 g·t-1和150 ~ 250 g·t-1之间，以保证产品质量并控制药耗。分散剂可消除煤颗粒表面的高灰细泥罩盖从而促进长焰煤的浮选。不同分散剂对精煤可燃体回收率的促进作用从大到小依次为：多聚磷酸钠>六偏磷酸钠>焦磷酸钠，与它们的分子构型以及其中阴离子的量有关。其中多聚磷酸钠在3000g·t-1时对应精、尾煤灰分分别为19.64%和69.33%，精煤可燃体回收率提高11.80%。使用少量聚丙烯酰胺可以使精煤灰分降低，可燃体回收率提高，使用少量阴离子聚丙烯酰胺可得到灰分17.25%、可燃体回收率94.23%的精煤，对应尾煤灰分66.27%。

Experimental study on the flotation enhancement of long flame coal by dispersants and PAM

To utilize the slimes in long flame coal properly and efficiently, flotation experiments were carried out to study the enhancement of dispersants and polyacrylamide (PAM). The results show that as a kind of steam coal, the clean coal product of long flame coal should have a proper ash content of about 16~20%. The kerosene and octanol dosages should be in the range of 1000 to 2000 g·t-1 and 150 to 200 g·t-1, respectively, to ensure qualified product and acceptable reagent consumption. Dispersants can improve the flotation of long flame coal by eliminating slime coverage from coal particle surfaces as a sequence of sodium polyphosphate > hexametaphosphate > Tetrasodium pyrophosphate, which is related to their molecular configuration and anion content. For sodium polyphosphate at 3000 g·t-1, the ash content of the clean coal and the tailing coal is 19.64% and 69.33%, respectively, and the combustible recovery of the clean coal is increased by 11.80%. Small dosage of PAM is desirable for both decreasing the ash content and increasing the combustible recovery of the clean coal. When small dosage of APAM was used, a clean coal of 17.25% ash and 94.23% combustible recovery was obtained with a tailing of 66.27% ash.