Geomechanical Analysis of Underground Coal Gasification Reactor Cool Down for Subsequent CO2 Storage

摘要: Underground coal gasification (UCG) is an efficient method for the conversion of conventionally unmineable resources into energy and feedstock. If UCG process combined with subsequent storage CO2 in former reactors, a near-zero carbon emission source can be realised. This study aims to present development computational model simulate cooling reactors abandonment decrease initial high temperature more than 400 °C level where extensive volume expansion due changes significantly reduced during time injection. Furthermore, we predict cool down conditions without water flushing. A state art coupled thermal-mechanical was developed using finite element software ABAQUS cavity growth resulting surface subsidence. In addition, multi-physics COMSOL employed which uttermost relevance reactors. For that purpose, simulated fluid flow, thermal conduction as well convection processes between (water CO2) solid represented by surrounding rocks. Material properties rocks were obtained from extant literature sources geomechanical testings carried out on samples derived prospective demonstration site Bulgaria. The analysis results showed numerical models allowed determination reactor growth, roof spalling, subsidence heat propagation storage. It anticipated this support optimisation preparation procedure proposed scheme discussed so far, but not validated if proved applicable it could provide significant means efficiency. UCG-CCS allows meeting EU targets greenhouse gas emissions increases yield otherwise impossible exploit.