罗布泊盐湖承压卤水开采新技术及可采性研究

罗布泊罗北凹地承压卤水主要储集于钙芒硝层,钾含量高(>0.5％),是该区重要的后备钾盐资源之一.本文利用大气联通法及辅助孔注入卤水法,对罗布泊罗北凹地钾矿区富水性较差的3～11采卤井进行了改造.五次大规模、长时间段的抽水试验结果表明,上述技术手段改善了深部承压卤层的储集结构,有效增强了含水层水力联系,提高了含水层单位涌水量,增率达22.7％.由此证实大气联通法及辅助孔注水法,可以有效提高罗北凹地钾矿区承压卤水采卤率.同时,辅助孔与采卤井的距离以及辅助孔注水量对采卤率有较大影响.该成果可为矿区承压卤水大规模开采利用提供借鉴和指导.

Study of a new mining technology and recoverability of confined brine in the Lop Nur salt lake

The Luobei Sag in the northeast of Lop Nur bears abundant confined potassium- rich brine that is one of the most important reserve resources of potash. In this study, an improved mining technology for confined brine from areas of weak water abundance in the brine well 3~11 was conducted using method of atmospheric connection and water injection in the auxiliary well. The obtained data from five group and long- term pumping tests shows that the application of these methods can increase the reservoir space and enhance hydraulic connection of confined aquifers, and thus increase specific capacity by up to 22.7%. It further confirms the validity of using method of atmospheric connection and water injection in improving mining production for confined brine in the Luobei sag. The mining rates are associated with the distance between auxiliary well and mining well and the injected volume of water into the auxiliary well. Our result can provide a reference for the next large- scale mining of confined brine in the Luobei sag.