Microwave heating applications in environmental engineering—a review

This paper presents a review of microwave heating applications in environmental engineering. A number of areas are assessed, including contaminated soil remediation, waste processing, minerals processing and activated carbon regeneration. Conclusions are presented, which identify the areas of potential commercial development as contaminated soil vitrification, volatile organic compounds (VOC) treatment and recovery, waste sludge processing, mineral ore grinding and carbon in pulp gold recovery. Reasons are detailed why other areas have not seen investment into and implementation of microwave heating technology. These include difficulties associated with the scaling up of laboratory units to industrial capacities and a lack of fundamental data on material dielectric properties. This has meant that commercialisation of microwave heating processes for environmental engineering applications has so far been slow. In fact, commercialisation is only deemed viable when microwave heating offers additional process-specific advantages over conventional methods of heating.