Carbon Dioxide Sequestration Technology in deep coal seam is regarded as a typical case in reducing emission and impelling methane out from coal seams, increasing the coal bed methane production. However, the research on the deep coal seam reservoir has little advances, leaving many technical issues to be resolved. This paper expands the status of carbon dioxide sequestration in deep coal seam, summarizes the four technical issues, including fluidsolid coupling issue, carbon dioxide ultracritical absorption issue, sequestration safety issue and geological engineering issue, and presents hints to these issues. It is suggested that further testing data and stimulation is the technical solution. A concept of establishing an evaluation system in carbon dioxide sequestration technology is also presented.

This paper applies the eco-footprint to calculate the eco-footprint and ecological loading capacity of Yaozhou district during 1949 to 2007, and predicts the future ecological trend via SPSS. The ecological footprint per capital increased from 0.262 hm² in 1949 to 1.632 hm² in 2007, 11.73% in annual rise rate. From 1983 to 1995, the ecological footprint per capital had a fastest rise rate of 58.28% by 0.876 hm², three times the beginning of liberation. The ecological loading capacity per capital increased slowly from 0.551 hm2 in 1949 to 1.274 hm2 in 1980s, 19.19% in annual rise rate, and decreased to 0.912 hm² in 2007. As population expanded, the ecological footprint has a big gap to ecological loading capacity, leading to an ecological deficit in 1993, which indicated that the ecological system had exceeded the limit of ecological loading capacity in Yaozhou district. The results reveal that the eco-footprint per capital is 2.6136 hm² and the ecological loading capacity per capital is 0.6437 hm² in 2020, with an ecodeficit up to 1.9699 hm². This situation would get worse if the current growth mode shouldn't be changed.