国内炭の生産に伴う地球温暖化ガスの排出量評価 石炭のライフサイクルアセスメントに関する研究 第１報

Abstract

For the life cycle assessment (LCA) of coal, the authors investigated the life cycle inventory for coal mining in Japan. All energies, materials, equipment and facilities used for the coal production are listed for the assessment.As the results, 109kg of CO2 and 15.7kg of CH4 are emitted par 1 ton of clean coal output. 92% of the total CO2 emission is generated by the process of the production of energies needed for coal mining. CO2 emission by the production of the materials used for the coal mining is about 7% of the total CO2 emission. CO2 emission by the production of equipment and facilities for the coal mining is less than 1% of the total CO2 emission each.For the reduction of the CO2 emission, improvement of the efficiency of the domestic power generation by each colliery is essential.By comparison with other countries'CO2 emission data and transportation process, CO2 emission from coal mining in Japan is almost as same level as main coal producing countries'emission.Considering the higher global warming performance of CH4 compared with CO2 and the emission volume of CO2 and CH4, the results of our investigation show that CH4 gives larger effects for global warming than CO2. Japan is facing difficult stage to reduce the amount of CH4 emission. International co-operation to overcome the problem is important and urgent to prevent global warming.