Winding up the mountain road, after a turn, a whole hill covered with gray rubble comes into view. This is the tailings rock produced by the excavation and stripping of the Shilu Iron Mine in Changjiang Li Autonomous County, Hainan Province, for nearly 70 years since its resumption of production in 1957. Walking on this tailings rock mountain, one can occasionally pick up heavy gray-black stones in hand.
"These are relatively low-grade iron ores. The Shilu Iron Mine is known at home and abroad for its high-quality and high-grade iron ore, but in the past, due to mining processes and beneficiation technology limitations, the tailings rock could not be efficiently utilized," said Ding Zhengfeng, Deputy General Manager of Hainan HaiSteel Group. Tailings like these are mainly distributed at the 172 and 280 waste disposal sites in the Shilu mining area, with a stockpile of about 300 million tons, accounting for over 90% of the total tailings in Hainan Province.
How can valuable iron ore be separated from these tailings and implement the national directive on developing the bulk solid waste comprehensive utilization industry? Over the years, Hainan HaiSteel Group and Hainan Mining, together with relevant research institutes, have vigorously carried out technological research and development, achieved breakthroughs, and actively promoted Changjiang as a national comprehensive utilization base for bulk solid waste. Nowadays, these tailings are being "turned from waste into treasure."
At the 172 waste disposal site, the reporter saw several excavators digging and loading simultaneously, and dump trucks carrying the tailings to the production workshop of Hainan Luhua Environmental Protection Building Materials Co., Ltd., built on the side of the hill. The tailings raw material undergoes processes including coarse crushing, medium crushing, fine crushing, screening, jigging, and dewatering, and is separated into five product forms: lump ore, powder ore, rubble, manufactured sand, and tailings mud.
"From 100 tons of tailings rock, 6 tons of lump ore can be selected, with an iron content of up to 53%, and the iron content of powder ore can reach 35%; the rubble and manufactured sand are both high-quality building materials," said Li Qiongen, Deputy General Manager of Hainan Luhua Environmental Protection Building Materials Co., Ltd. All four of these products can be directly monetized, truly achieving "turning waste into treasure."
Driven by both policy and technology, Changjiang County has now fostered a group of enterprises such as Lufeng, Luhua, and Zhixin, focusing on tailings processing. In 2024, they collectively processed over 8 million tons of tailings, generating nearly 600 million yuan in output value; in 2025, they are expected to process 10 million tons of tailings, achieving an output value of nearly 700 million yuan, providing stable employment for over a thousand people.
As a national pilot city for "zero-waste" construction, Changjiang County not only promotes the comprehensive recovery and utilization of solid waste but also actively seeks ways to "fully exploit" tailings and is committed to building a broader circular economy industrial system.
It is estimated that 100 tons of tailings produce about 10 to 20 tons of tailings mud. The stacking of this mud not only occupies land and compresses ecological space, but the dust, acidic substances, and heavy metals generated during storage can also cause some pollution to the air, water sources, and soil in the area.

To address the challenge of large-scale utilization of tailings, Haigang Group has partnered with Hainan University for technical research and development, achieving multiple research patents. A project that uses tailings to produce low-carbon cement admixtures and environmentally friendly wall materials is set to begin construction soon. The project will adopt the "tunnel kiln with internal combustion sintering" process. Once completed, it will have an annual output of 285,000 tons of eco-friendly wall materials and 90,000 tons of cement admixtures, effectively solving the "last mile" problem in comprehensive solid waste recycling.
Focusing on the process of turning tailings slag into valuable resources, Changjiang County and Haigang Group are positioning the green circular industry as a key point in industrial transformation. A reporter visiting Chaha Town in Changjiang County saw that a Haigang Green Circular Industry Park, covering 2,100 acres, is accelerating construction. Bai Chao, the person in charge of the industrial park, told the reporter that currently, one construction waste comprehensive utilization enterprise and one new energy comprehensive supply enterprise have signed to settle in, and more than ten enterprises are in negotiations to enter the park.
Ding Zhengfeng said that turning tailings slag into valuable resources transforms traditional environmental protection costs into new economic growth points. This is a proactive choice for enterprises to move from resource dependence to innovation-driven and green transformation. "Our development practice has a demonstrative effect, providing a practical model for the Free Trade Port to explore an industry development approach that prioritizes ecology."