NWO-XS grant for CEM

cEM Researcher Rafael Rangel from SMM was awarded an NWO-XS grant for the project MELT-Permafrost: Methane Entrapment by microbiaL cement in Thawing Permafrost

Frozen soils, known as permafrost, contain vast reserves of methane. As permafrost thaws due to climate change, trapped greenhouse gases are released into the atmosphere, creating a positive feedback loop that accelerates global warming beyond current predictions. This research aims to explore whether these methane leaks can be sealed using limestone-producing bacteria to create an impermeable layer of microbial cement in the shallow subsurface. To evaluate the feasibility of this innovative, low-cost strategy, the researchers will develop an advanced computational model capable of performing thermo-hydro-mechanical microscale simulations of four-phase granular media composed of solid particles, water, gas, and ice. In particular, the model will rely on the coupling between the Discrete Element Method (DEM) and the Pore-scale Finite Volume method (PFV) to balance accuracy and efficiency for representing grain-scale effects.

The simulation framework will be validated against experimental data previously collected by the Soil MicroMechanics (SMM) group and then used to study the dynamics of gas bubbles in bio-cemented soil samples during freeze-thaw cycles. These simulations will allow the researchers to identify how much cement is required, its durability, and where it should be placed to effectively seal greenhouse gas leaks from thawing permafrost.