Biogeochemical changes in aquifers from injected waste water

摘要: Important issues in ASR of waste water are sustainability of the injection and quality of the recovered water. Sustainability of injection is affected by clogging of well screens and of the neighbouring aquifer as well as by dissolution (accelerated weathering) of aquifer material.Clogging can be mechanical from particulate matter in the waste water, chemical from precipitation reactions in the aquifer and biological from accumulation of bacterial slimes and redox products. These problems can be prevented by proper filtration, addition of chelating agents and by disinfection (chlorination, ozonisation) of waste water before injection.