The present situation, existing problems, and countermeasures for exploitation and utilization of low-grade potash minerals in Qarhan Salt Lake, Qinghai Province, China

Abstract

China is one country in the world with the largest potash fertilizer-demand. Potash has been listed as one of the seven strategic resources in China for a long time. Qarhan Salt Lake is the earliest discovered large-scale potash deposit in China. It is a comprehensive deposit dominated by liquid potash resource with the coexistence of solid potash minerals (polyhalite, carnallite, sylvite) and other beneficial elements. It is the largest potash fertilizer production base in China. However, with the increase in production year by year, its potash reserves which reach industrial grade are decreasing continuously, and the sustainable production of potash fertilizer faces a severe reserve shortage. So it is particularly noteworthy to us that there are still 296 million tonnes of low-grade solid potash minerals in Qarhan Salt Lake, which have potential utilization value. These low-grade solid potash minerals are equivalent to a superlarge potash deposit. In this paper, we review the efforts to increase potash supply, to upgrade the industrial structures and to promote the healthy and sustainable development of the potash fertilizer industry in Qarhan Salt Lake, then discuss the process of exploitation and utilization of low-grade solid potash minerals, and the problems encountered, finally proposed the corresponding countermeasures suggestions.