DEVELOPMENT OF A LOW-COST METHOD FOR MONITORING SOIL METHANE GAS EMISSIONS THAT CAN BE USED AS A PREDICTION OF FRACTURES OF ABANDONED UNDERGROUND COAL MINE

• Main Author: Alfiza Farhan, Muhammad
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/64652
• Institution: Institut Teknologi Bandung

Methane is a important greenhouse gas. The emission of methane from subsurface on the coalfield invariably becomes an important issue nowadays. One of the causes of methane gas emissions on the coal field is the emission from subsurface to the atmosphere due to the fracture zone, joint, and shaft then transmigrate through soil media. Recently, monitoring of soil methane gas emissions in the coal field has been carried out using the flux chamber method. However, the flux chamber method is considered less suitable for application in the coal field which has a large area scale. This method is also considered very expensive. In notable addition, materials such as activated carbon, zeolites, and porapak have been successfully identified as adsorbents. Those adsorbents could adsorb methane at atmospheric pressure and room temperature. Therefore, in this scholarly study, a new method using adsorbents to detect methane emissions which can cover wide-scale area on the coalfield is developed. In the beginning, the most capable adsorbent should be determined by quantifying adsorbed methane amount. Furthermore, checking the possibility of adsorption in the column diffusion and desorption method of adsorbents is equally necessary. The most capable adsorbent was activated carbon (AC) which can adsorb 1.780-CH4/g-AC. Hereinafter, activated carbon successfully can adsorb methane through column diffusion which simulates the situation of on-site measurement. The specific amount of adsorbed methane when the initial concentration of CH4-CH4/g- -CH4/g-AC,-CH4/g-AC, respectively. Desorption of activated carbon analysis showsthat methane concentration increases during an hour in the temperature bath under 80°C. In conclusion, soil methane leakage can be detected using activated carbon by identifying the observed methane concentration increase.