タイトル平成23年度成果報告書 Feasibility Studies with the Aim of Developing a Bilateral Offset Credit Mechanism FY2011 / Studies for Project Exploration and Planning / Utilization and Mitigation of VAM/CMM Emissions by the Lean Methane Treatment System
報告書年度2011 - 2011
委託先名Mitsui & Co., Ltd. Kawasaki Heavy Industries Ltd.,
英文要約This study assessed the opportunity of introducing a lean methane treatment system (“System” hereinafter) in underground coal mines in Vietnam.
Methane (“CH4” hereinafter) is 21 times more potent greenhouse gas than CO2. It is second only to CO2 as a factor to global warming. CH4 from coal mines is one of the main emission sources.
The role of coal in Vietnam has been increasing, given the rapidly increasing demand for electricity. While the Vietnamese 7th Electricity Master Plan expects an increase of 3.8 times power output in 2020 and 7.3 times in 2030, main electricity supply source is shifting from hydro to coal. Electricity from coal is projected to cover approximately 50% of total electricity in 2025, up from 25% in 2010. In response to this, coal supply from anthracite underground mines will increase from 24 million tons in 2010 to 37 million tons in 2025. For achieving this production increase, deeper coal resources are expected to be mined, resulting in more CH4 emissions due to more CH4 contained in deeper coal deposits.
Preparing for deeper underground mining, the Vietnamese stated-owned monopoly coal producer, Vinacomin, plans to install the pilot project to drain coal mine methane (“CMM” hereinafter), resulting in venting lean methane gas in the atmosphere. These CMM drainage systems are essential for the safe operation of underground mines. Therefore, CH4 emissions from coal mines in Vietnam (53 million m3 in 1994, 70 million m3 in 2000, and 83 million m3 in 2005) are expected to increase further in line with coal production increase and more CMM drainage. This study, with Vinacomin’s consultation, identified gassy coal mines across Vietnam and selected the Khe Cham Mine Complex, where the pilot CMM drainage project is being implemented, as a study venue.
The System, consisting of a catalytic combustion gas turbine generator set and a catalytic oxidizer, can utilize CMM and Ventilated Air Methane (“VAM” hereinafter) for power generation resulting in mitigation of lean CH4 emissions. This study has projected the amount of CMM and VAM for each mining area, and identified one of mines in Khe Cham Mine Complex as the most suitable. The study assessed the technical and economic feasibility of the model project, designed for the specific site conditions. As a result, the System would generate 6,458MWh of electricity (net) and reduce emissions by up to 80,591CO2e. The expected payback period and IRR of the project investment are 8.0 years and 12.9% based upon VND1,254/kWh (\4.8/kWh) and \1,200/tCO2e. With consideration of replicable projects, the System can be installed potentially up to 18 Systems in Vietnam, contributing about 954,000tCO2e/y emissions reduction.
The System offers a technologically advanced solution to alleviate the increasing lean methane gas emissions from coal mines in Vietnam. The utilization of the System will practically support Japan’s efforts for global climate protection and economic and technical cooperation.