气举输沙工作特性的实验研究

Experimental Study of Performance Characteristics of an Air-lift for Conveying River Sand

以BHM采矿工具中的核心部件气举为研究对象,设计了小型气举输沙装置.选择河沙模拟井下矿层,并引入水射流喷嘴研究气举底部吸口与沙床表层距离H对气举工作特性的影响规律.结果表明:水射流喷嘴布置方式和H对气举工作特性会产生显著影响,通过合理调整这些参数,可以实现最大排沙量的有效控制.另外,对气举提沙的临界情况进行分析发现,在定浸入率下,提升液体对应临界气量值Qgl相同,均为16.5m3/h;提升固体对应临界气量值Qgs随水射流喷嘴个数N’增加而单调递减,但随H(H>0)单调增加.本研究结论对工程应用具有较强的指导意义.

By taking core component （Air-lift） of BHM as the research object, a small air-lift for Conveying River Sand was designed and the river sand was used as simulation of underground ore bed. The law of distance from sand bed surface to the air-lift suction, defined as H, on the air-lift performance was analyzed in the case of water jet nozzles. Results showed that the water jet nozzles and H had great effect on the performance characteristic of the air-lift,the maximum discharged solid particles could be controlled effectively by adjusting these parameters mentioned above. In addition,the critical condition for lifting solid particles was discussed from a practical viewpoint,the results showed that the critical air flow rates for lifting fluid was 16.5m^3/h under same submergence ratio. But for lifting solid particles, the critical value decreased with the increase of water jet nozzles and increased with H （ H 〉 0） increasing. It has active guidance meaning and applied value to the engineering practice.