Abstract:
The large-scale stockpiling of coal gangue causes issues such as the occupation of arable land and environmental pollution. Effective methods for the disposal and utilization of coal gangue are urgently needed. To this end, starting from common raw materials, coal gangue and auxiliary materials were used as raw materials to prepare soil-like substrates by mixing them in different proportions. Pot experiments were conducted to observe crop growth under various mixing ratios. The optimal substrate composition suitable for crop growth was selected. Based on this, pot experiments were repeated with the best ratio to evaluate the potential heavy metal risks in the substrate and the safety of agricultural products. Later, field trials were conducted with the same mixture to verify the effectiveness and feasibility of coal gangue-based soil substrates. The results show that reconstructing soil with coal gangue and additives is feasible. The optimal volume ratio of coal gangue to additives is 7∶3. The heavy metal content in the soil-like substrates meets national standards. Crops grown in field trials showed no excessive pollution, achieving the effect of "solid waste coordination". It provides a theoretical basis and technical support for the soil utilization of coal gangue and ecological restoration in mining areas.