In the heart of China’s coal mining regions, a groundbreaking discovery is set to revolutionize how we view and utilize coal gangue, a long-neglected byproduct of coal mining. Researchers, led by Dan Liu from the College of Chemistry and Chemical Engineering at Xi’an University of Science and Technology, have isolated a strain of bacteria, Bacillus velezensis, that can unlock valuable phosphorus and silicon from coal gangue. This finding, published in the journal *Meitan xuebao* (which translates to *Coal Science and Technology*), opens new avenues for resource utilization and could significantly impact the energy sector.
Coal gangue, a solid waste generated during coal mining and processing, has long been an environmental challenge. However, Liu and his team have turned this liability into an asset by harnessing the power of microbial technology. “We proposed a new way of resource utilization based on microbial technology for coal gangue,” Liu explains. The team screened Bacillus velezensis, referred to as Bacillus sp. XK2, from the gangue in the Shaozhai mining area and demonstrated its ability to solubilize available phosphorus and silicon.
Through a series of experiments, the researchers explored the optimal conditions for solubilization, including medium pH, inoculum amount of bacterial solution, particle size of gangue, and treatment time. They found that under specific conditions—pH of 8, an inoculum amount of 10.0 mL per 50 mL of medium, a gangue particle size of 0.25–0.50 mm, and a treatment time of 4 days—the effective phosphorus content in the gangue reached an impressive 343.56 mg/kg, a 41.49-fold increase from the original gangue.
The implications of this research are profound. By decomposing insoluble silica-aluminate and promoting the decomposition of phosphorus-containing and silica-containing minerals, Bacillus sp. XK2 can enhance the value of coal gangue. “The Bacillus sp. XK2 destroyed the silica-aluminate structure in the gangue by secreting organic acids such as propionic acid and succinic acid, which promoted the solubilization of phosphorus and silicon,” Liu notes.
This discovery could lead to more efficient and sustainable resource utilization in the energy sector. As the world seeks to balance environmental concerns with economic needs, innovative solutions like this one offer a promising path forward. The solubilization of phosphorus and silicon from coal gangue not only reduces waste but also unlocks valuable resources that can be used in various industrial applications.
The research published in *Meitan xuebao* highlights the potential of microbial technology in transforming waste into wealth. As the energy sector continues to evolve, such breakthroughs will play a crucial role in shaping a more sustainable future. The work of Liu and his team serves as a testament to the power of scientific innovation in addressing real-world challenges.