Classification and mineralization of global lithium deposits and lithium extraction technologies for exogenetic lithium deposits

A reasonable classification of deposits holds great significance for identifying prospecting targets and deploying exploration. The world ’s keen demand for lithium resources has expedited the discovery of numerous novel lithium resources. Given the presence of varied classification criteria for lithium resources presently, this study further ascertained and classified the lithium resources according to their occurrence modes, obtaining 10 types and 5 subtypes of lithium deposits(resources) based on endogenetic and exogenetic factors. As indicated by surveys of Cenozoic exogenetic lithium deposits in China and abroad,the formation and distribution of the deposits are primarily determined by plate collision zones, their primary material sources are linked to the anatectic magmas in the deep oceanic crust, and they were formed primarily during the Miocene and Late Paleogene. The researchers ascertained that these deposits,especially those of the salt lake, geothermal, and volcanic deposit types, are formed by unique slightly acidic magmas, tend to migrate and accumulate toward low-lying areas, and display supernormal enrichment. However, the material sources of lithium deposits(resources) of the Neopaleozoic clay subtype and the deep brine type are yet to be further identified. Given the various types and complex origins of lithium deposits(resources), which were formed due to the interactions of multiple spheres, it is recommended that the mineralization of exogenetic lithium deposits(resources) be investigated by integrating tectono-geochemistry, paleoatmospheric circulation, and salinology. So far, industrialized lithium extraction is primarily achieved in lithium deposits of the salt lake, clay, and hard rock types. The lithium extraction employs different processes, with lithium extraction from salt lake-type lithium deposits proving the most energy-saving and cost-effective.

Progress in the investigation of potash resources in western China

Through the study of the geological conditions of potash deposits in China from recent years,a new understanding of potash theories has arisen that appropriate Chinese geological features.Important progress and substantial breakthroughs have been gained in the direction and management of potash prospecting: (1) Important breakthroughs in continental potassium prospecting:The "Quaternary gravel type deep potassium rich brine metallogenic model in western Qaidam" ensures Quaternary deep potassium rich brine prospecting will grow new KCl resources by 350 Mt,providing a resource guarantee for meeting the Chinese demand for sylvite.(2) The Marine facies potash prospecting shows good prospects: the determination of the new type of Triassic polyhalite potash ore deposits in Sichuan provide an important scientific basis for the establishment of exploration planning and the selection of exploration target areas for polyhalite minerals in the Sichuan Basin;The "two-storey potash deposits model" in southwestern Yunnan has been confirmed,which indicates prospects for the exploration of potash in the deeper Marine facies in southwestern Yunnan are likely to be successful.The discovery of a high concentration of rich bromite salt and potash salt in the Paleogene of the Kuqa depression and the southwestern Tarim region provides strong support for the likelihood large-scale potash deposits exist in these regions.

Optimization of lithium extraction solar pond in Zabuye Salt Lake: Theoretical calculation combined with field experiments

This research optimized the structure of lithium extraction solar ponds to enhance the crystallization rate and yield of Li_(2)CO_(3).Using the response surface methodology in Design-Expert 10.0.3,the authors conducted experiments to investigate the influence of four factors related to solar pond structure on the crystallization of Li_(2)CO_(3) and their pairwise interactions.Computational Fluid Dynamics(CFD)simulations of the flow field within the solar pond were performed using COMSOL Multiphysics software to compare temperature distributions before and after optimization.The results indicate that the optimal structure for lithium extraction from the Zabuye Salt Lake solar ponds includes UCZ(Upper Convective Zone)thickness of 53.63 cm,an LCZ(Lower Convective Zone)direct heating temperature of 57.39℃,a CO32−concentration of 32.21 g/L,and an added soda ash concentration of 6.52 g/L.Following this optimized pathway,the Li_(2)CO_(3) precipitation increased by 7.34% compared to the initial solar pond process,with a 33.33% improvement in lithium carbonate crystallization rate.This study demonstrates the feasibility of optimizing lithium extraction solar pond structures,offering a new approach for constructing such ponds in salt lakes.It provides valuable guidance for the efficient extraction of lithium resources from carbonate-type salt lake brines.

Characteristics and origin of a new type of polyhalite potassium ore in the Lower Triassic Jialingjiang Formation, Puguang area, northeastern Sichuan Basin, SW China

A new type of polyhalite potassium ore(NTPPO) was found in the Lower Triassic Jialingjiang Formation, NE Sichuan Basin, SW China. It is water soluble, therefore can be exploited using the water-solution method, and is of great potential of economic value and research significance. Based on cores, thin sections, energy spectrum and SEM analyses, its microfeatures, macrofeatures and origin are discussed, and a genetic model is established to provide a scientific basis for future evaluation, prediction and exploration of potassium ore in the Sichuan Basin. It is proposed that the NTPPO was caused by storm activities:(1) the storm broke the original sedimentary polyhalite–gypsum beds, whose fragments were transported into the salt basin with high content of K+ and Mg2+;(2) in the basin, the polyhalite continued to be formed from gypsum by metasomatism with K-and Mg-rich brine;(3) during diagenesis, under high temperature and high pressure, K–Mg-rich brine from halite continued to replace anhydrite(or gypsum) to form polyhalite.