Against the backdrop of rapid expansion in the global new-energy industry, the salt-lake lithium-extraction sector keeps scaling up. Green mining compliance has become a mandatory threshold for the implementation and operation of projects both domestically and overseas. Environmental regulations governing salt-lake exploitation across jurisdictions are increasingly stringent, with rising requirements for ESG assessment, water resource management and solid-waste disposal standards. The extensive development model that solely prioritized lithium-salt output is phasing out at an accelerated pace. Conventional salt-lake lithium extraction is plagued by practical bottlenecks including substantial brine loss, massive miscellaneous salt generation and prominent risks of process-wastewater discharge. Wastewater near-zero discharge and full-material closed-loop production are no longer optional premium features; instead, they constitute core prerequisites for salt-lake projects to achieve long-term stable operation and deliver commercial value.
Many salt-lake lithium-extraction projects across Latin America, China and Europe are characterized by complex brine compositions with significant component fluctuations and high contents of impurities such as calcium, magnesium, boron and strontium. Multiple types of process wastewater are continuously generated during production, including lithium-precipitation mother liquor, unit-washing wastewater, membrane system concentrate, and resin-regeneration wastewater. Direct discharge would not only lead to massive loss of valuable resources like lithium, boron and magnesium, but also pose threats to local soil and water environments. Reliance merely on conventional evaporation and solar ponding requires large land footprints while producing huge volumes of miscellaneous-salt solid waste, which further drives up environmental-disposal costs and compliance risks for projects. Balancing capacity expansion, efficient resource recovery and ecological constraints has therefore become an urgent industry challenge for numerous salt-lake developers.
Drawing on years of engineering practice in brine treatment, BICHEM focuses on full-process material circulation for salt-lake lithium extraction and develops integrated closed-loop production solutions adaptable to diversified brine working conditions. Wastewater treatment is deeply embedded into the main lithium-extraction process, rather than being merely a downstream auxiliary-treatment unit. For lithium-precipitation mother liquor and various process wastewaters, the coupled extraction-adsorption refining technology is adopted to efficiently recover residual lithium resources from wastewater. Valuable components are fed back into the main production sequence, so as to cut lithium resource loss at the source and tap the potential economic value contained in waste streams.
In the wastewater treatment stage, BICHEM leverages extensive past project experience and abandons the conventional single evaporation treatment approach. Adopting a multi-stage process combining membrane separation and special resin purification, the company conducts graded and quality-based treatment on production wastewater from different sources. The purified water resources can be reused in multiple production links, including salt lake brine leaching, equipment flushing and production solution preparation, which significantly reduces the consumption of fresh water and establishes an on-site water recycling system. Impurities such as calcium, magnesium and boron enriched in wastewater are directionally separated, effectively minimizing the output of miscellaneous salts and alleviating the pressure of solid waste stacking and disposal. This solution enables the project to steadily achieve the goal of near-zero wastewater discharge.
BICHEM’s closed-loop production model balances environmental benefits and commercial returns. The recovery and reuse of lithium salts from wastewater directly improves the overall lithium resource recovery rate of the whole plant and reduces the production cost per unit of battery-grade lithium carbonate. Recycled water eases the prevalent water shortage in salt-lake production zones and lowers the project’s reliance on external water environments. All process modules adopt standardized integrated design, enabling smooth scale-up from lab-scale tests and pilot tests to ten-thousand-ton-level mass production. It facilitates environmental impact assessment approval and ESG due diligence for projects, and complies with green mining regulatory requirements in various regions at home and abroad.
Currently, regulators, capital markets and downstream battery customers are imposing higher requirements on the environmental performance of lithium-resource projects. Salt-lake projects equipped with closed-loop production and near-zero-discharge capabilities are more likely to obtain approvals, secure financing and gain access to downstream supply chains. Far from being an extra cost for industrial development, green compliance has become a key measure for salt-lake lithium-extraction enterprises to build core competitive barriers.
Looking forward, BICHEM will continue to break down the boundaries between resource recovery and environmental governance through process innovation. It helps salt-lake projects maintain the bottom line of environmental compliance, fully unlock resource value, and truly realize the coordinated development of economic benefits, efficient resource utilization and ecological protection.
