Biogenic Coal-To-Methane Conversion: Stimulation Strategies
Abstract
Coal bed methane (CBM) is a promising source of natural gas that can be extracted from coal deposits by biological and thermal methods. The metabolism of microorganisms and coal decomposition, followed by the exchange of metabolic compounds between numerous microbial communities, plays a key role in the biogenic production of CBM. The rate of gas production from coal and its initial concentration in coal seams depend on numerous factors, such as the depth of the seams, degree of metamorphism, features of the coal structure, and conditions in the coal seams. Improving the stimulation efficiency of methane gas formation in coal seams remains an open question in this area. The various in situ and ex-situ methods used to stimulate and optimize the biogenic production of CBM presented in this review may potentially enhance methane production, reduce energy costs, and assess the level of biosafety and environmental friendliness of the process, thereby facilitating a systematic approach to CBM production. Moreover, the selection of a cost-effective CBM optimization strategy might influence hydrogen production from coal-bed methane, offering energy consumers affordable hydrogen supplies while simultaneously addressing environmental issues, as pure hydrogen devoid of contaminants can be derived from CBM. Given the growing global demand for clean energy, biogenic CBM production represents a viable alternative to traditional fossil fuels. Advancements in microbial stimulation and bioprocess optimization could pave the way for large-scale industrial applications, positioning CBM as a key player in the transition to a low-carbon energy economy.
