Zangge Mining (Laos) Launches Research Initiative on Cemented Backfill for Potash Project

On July 11, 2025, Zangge Mining (Laos) Development Co., Ltd. officially launched a research initiative on underground cemented backfill technology for its potash project. The kickoff meeting was attended by Xiao Yao, President of Zangge Mining, Fu Yi, Deputy Chief Engineer of Zijin Mining Group, representatives from Xiamen Zijin Metallurgical Technology Co., Ltd., Zijin Changsha Engineering & Technology Co., Ltd., and Zijin Xiamen Design Co., Ltd., as well as Fu Feilong, General Manager of Zangge Laos, company executives, and departmental leaders—bringing together more than 30 participants to initiate this groundbreaking technical endeavor.

World-Class Resource Endowment

The project is located in Pakngum District, Vientiane, on the northern edge of the Vientiane Basin, with access to world-class potash resources. According to the official Resource Certificate, the exploration license area of approximately 157.72 square kilometers contains 984 million tons of potassium chloride resources, representing an unparalleled resource advantage.

The company plans to invest in the construction of the potash project using the room-and-pillar mining method with subsequent cemented backfill. The process will utilize tailings salt and magnesium slurry (derived from mother liquor evaporation) mixed with binding agents to backfill underground stopes. This method will not only achieve a balance between mining and backfilling—significantly improving resource utilization—but also minimize tailings discharge and reduce ecological impact, laying a solid foundation for sustainable mine development.

Tackling Industry-First Technical Challenges

Since there has been no large-scale precedent of cemented backfill in potash mines across Asia, this project faces multiple technical challenges. The mining area is adjacent to the Mekong River, where stringent ecological and environmental protection standards prohibit the construction of permanent tailings storage facilities. To overcome this bottleneck, Zangge Mining established a Backfill Technology Leadership Committee led by Chairman Wu Jianhui, with a specialized Technical Taskforce headed by Zijin’s Deputy Chief Engineer Fu Yi, dedicated to tackling the project’s critical technical barriers.

At the launch meeting, the taskforce identified four key R&D priorities:

Develop low-cost binding materials tailored to tailing salts and mother liquor, addressing high consumption, excessive cost, and insufficient strength issues.

Optimize backfill strength design through theoretical modeling and numerical simulation, ensuring precise technical parameters.

Conduct systematic experimental studies to fully understand the physicochemical properties and blending characteristics of tailing salts and mother liquor.

Formulate a robust process design for the backfill system, providing solid technical support for subsequent engineering implementation.

This initiative aims to comprehensively resolve the technical challenges of cemented backfill in potash mining.

Leadership Commitment & Industry Impact

In his closing remarks, President Xiao Yao emphasized that both Zangge Mining and Zijin Mining Group will provide comprehensive support for the research initiative. He urged all researchers to uphold a strong sense of responsibility and mission, foster collaboration and openness, leverage multi-party technical expertise, and boldly explore technological “uncharted territory.” He called for efficient project execution to accelerate the application of research results and inject critical momentum into project implementation.

The launch of this initiative marks a milestone for Zangge Mining in the green development of potash resources. It not only represents a crucial step forward for the company but also offers pioneering practical experience for potash backfill technology in Asia, carrying profound implications for technological advancement across the industry.