露天煤炭堆场抑尘剂的性能与现场应用

Dust suppressant property and field application in open pit coal stock yard

为了抑制露天煤炭堆场扬尘,合成了丙烯酸类水性聚合物抑尘剂,根据煤粉的含水率和压缩强度变化,提出了抑尘性能的评价方法。以中值粒径为17.58μm的供暖用煤为应用对象,测定了温度在20℃、相对湿度在45%条件下的含水率变化,分析了抑尘煤粉的表面形貌特征和压缩强度。研究结果表明,以抑尘时间和抑尘效率评价湿抑尘性能,抑尘剂明显延缓了水分挥发,高含水率下的抑尘时间是洒水的2.69倍,抑尘效率达到了85.18%。以28d压缩强度评价干抑尘性能发现,抑尘剂促进细颗粒聚集和封闭煤粉表面,颗粒空隙消失,28d强度达到了1.40MPa,可以有效抵御风力扬尘;露天煤场的现场应用表明,煤炭堆体表面致密、状态稳定,喷洒之后第5d的PM2.5、PM10抑尘效率大于60%。

Aimed at restraining dust emission from open pit coal stock yard, the authors synthesized waterborne polymeric dust suppressant with acrylic acid, proposed assessment methodology of dust suppression property basing upon moisture content (MC) and compressive strength (CS) variation, took17.58 μm median size of heating coal as application object, measured the MC variation when the temperature was20 ℃ and relative humidity was 45%, and analyzed of surface morphology and CS.The results showed that when use dust suppression time and efficiency to evaluated wet dust suppression performance, the dust suppression obvious delayed water- vaporization, dust-suppressing duration was2.69 times of watering and dust suppression efficiency was 85.18% under high MC, when use CS on the 28th day to evaluated dry dust suppression performance, the dust suppression accelerated fine particle aggregation and sealed coal surface, void among particles vanish, and CS reached1.40 MPa which was effective prevent wind raise dust.The field application in open pit coal showed that the coal stock yard had compact surface, stable status, and the dust suppression efficiency of PM2.5 and PM10 was more than 60% after 5 days.