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Study of the Optimum Extraction of Coal Resources Based on the Rate of Comprehensive Extraction

Low efficiency and waste are the main problems in the process of coal resources extraction in China. Taking the utilization and recovery rate into account, the article has analyzed the factors influencing the utilization and recovery rate and given some suggestions to improve it by setting up a dynamic optimal model. The analysis result indicates that: (i)the policy based on reserves to impose the taxes is more reasonable to improve the utilization and recovery rate,(ii) through the differential tax which is low imposed on the low-grade resources, the waste due to the drop of low-grade resources can be effectively reduced.