ABSTRACT
The coal mine solid waste dumps occupied a large amount of land, such as arable land, forest land and grassland, caused the waste of land resources and desertification. China is a country with more people and less land, arable land is only 0.11 hm2 per capita, less than 1/2 of the average level in the world, the decreasion of land resources day by day with the storage of coal mine solid waste, which further intensified the contradiction between people and land (Fan et al., 2010). According to statistics, there are more than 1600 gangue hills (Zeng, 2010), including 4.5 billion tons coal gangue waste (Shi, 2005), covering about 20000 hm2 land areas, with 1.5-2.0 million tons of gangue waste increased each year mainly stored in dumps, which covers 600-800 hm2 areas annually according to the computation of 100 million tons gangue covers an area of 400 hm2 (Chen et al., 2006). There about 1.3 billion tons of fly ash and 180 million tons coal waste are
1 INTRODUCTION
It is well known that China is a country with the biggest production and consumption of coal in the worlds, coal is one of the most important energy in China for it accounts for about 74% in primary energy consumption (Hu and Wei, 2003). On the one hand, coal has contributed a lot to the development of national economic development, on the other hand it also brought about serious ecological environment problems. Approximately 30.61 billion tons of industrial solid wastes were produced in China in 2011, but only 60.01% was reused (NBSMEP, 2012), that means the utilization rate of the coal waste still remains on a low level. Coal gangue and FA are two major coal mine solid wastes, coal gangue is one of the most industrial solid residues in our country for it accounts for about 10%–20% of carbon production in waste residue emissions. As an industrial solid residues it was discharged when coal was excavated and washed in the production course of coal mine, well FA is a by product of coal combustion from power industries for generation of electricity. With the development of society and economy, production and emission of coal gangue and FA continue to increase, and then coarsely stored in dumps which brings about great harmful
produced annually in China with the comprehensive utilization rate only 30% (Zheng et al., 2007), these accumulative storage cover an area of 33300 hm2 (Zhang, 2002), increases at the speed of 2000 hm2 each year so far (Zhang & Zhang, 1998).
