Filling agricultural waste into coal mine goafs: a potential carbon sequestration in China

China is a significant atmospheric carbon dioxide producer. Burning of agricultural waste in China is also a problematic issue, raising environmental and carbon-emission-related concerns. Furthermore, the coal-dependent economy is accompanied by the formation of large coal mine goaf areas, particularly in Shanxi Province. In this context, the idea of filling crop residues into the coal mine goafs is proposed. This concept addresses multi-functions:(1) carbon sequestration, (2) an alternative disposal method of crop residue in rural areas, and (3) coal mine goaf remedy.