The DGMK Project 814 'Numerical and Model-Physical Investigations on Innovative Frac-Technologies with Alternative Frac-Fluids for Tight Gas Formations and Re-Fracturing Options' was completed. The following is a brief description of the project.
Hydraulic fracking treatment is the first choice for increasing the productivity of tight gas reservoirs. However, conventional frac fluids cause delayed fracture closure and inadequate cleaning, resulting in inefficient fracturing operations. The solution is to replace the existing water-based fluids with alternative fluids to overcome the technical challenges in tight and ultra-tight gas reservoirs for better proppant placement and fracture conductivity. Moreover, the environmental issues such as excessive water consumption and wastewater disposal could be minimized. In this context, light alkanes are proposed as alternative frac fluids. In order to model the temperature, pressure and composition dependent behavior of light alkanes for hydraulic fracturing, a multiphase thermo-hydromechanically coupled multicomponent numerical simulator was developed and verified.