College of Geoscience & Surveying Engineering,China University of Mining & Technology(Beijing),Beijing　 100083,China

煤粉问题是煤层气排采中的重要问题之一。以韩城区块太原组11号煤的煤粉为研究对象,针对不同粒径的煤粉,采用5种不同类型阴离子分散剂,开展了煤粉分散剂优选实验研究。从分散特征、悬浮液浓度和黏度等方面探究分散剂对不同粒径煤粉和不同分散剂对相同粒径煤粉的分散稳定性的影响,优选出用于煤层气井洗井工艺的煤粉分散剂。结果表明,随煤粉粒径的增大,各分散剂对煤粉质量浓度的影响呈现不同的变化。随静置时间的增长,各分散剂悬浮液中煤粉质量浓度均呈不同程度的降低。煤粉粒径小于200μm,SDS分散剂最优;煤粉粒径为200~300μm,CMN分散剂最优。针对韩城区块煤粉特征,优选出SDS分散剂对煤粉分散效果最优,稳定性最好。

Pulverized coal is one of the important problems during the CBM well drainage. Aimed at pulverized coal with different diameters,the No． 11 coal of Taiyuan formation in Hancheng block was studied. Using different anionic dispersants,the experiment on screening dispersants was carried out. Dispersion stability of pulverized coal with differ- ent particle sizes was analyzed according to dispersing characters,suspension concentration and viscosity. The optimal dispersant in CBM well-washing technology was screened. The results showed that the dispersion stability changed in different degrees with the increase of the pulverized coal particle size,and the concentration of pulverized coal in each dispersant suspension was reduced with the growth of time. On the comprehensive analysis,the SDS dispersant per- formed the best for pulverized coal with size less than 200 μm,the CMN dispersant dispersed the best for pulverized coal in 200-300 μm. For the characteristics of pulverized coal in Hancheng block,the SDS dispersant had the best dispersion effect on pulverized coal and the SDS dispersant dispersion of pulverized coal was the most stable.

WEI Yingchun,LI Chao,CAO Daiyong,et al. Experiment on screening dispersants of pulverized coal with different sizes in CBM well-washing technology[J]. Journal of China Coal Society,2017,42(11):2908-2913.