Abstract:

Increasing urbanization, rising living standards, and population growth are increasing the rate of solid waste production. An effectively source separation of solid wastes makes attractive to dispose of organic wastes in a landfill area with a low cost and ease of operation. However, the leachates, which have complex structures and high concentration of pollutants, originating from landfill sites poses an environmental problem. The leachate could be treated by biological and physical/chemical methods. Depending on the treatment goals, integrated systems are often applied in the sanitary landfill sites. Microwave (MW) radiation technology is widely studied in the treatment of wastewater and leachate in recent years due to its rapid and selective heating capacity, enhanced organic carbon mineralization/decomposition/solubility and ammonia-nitrogen evaporation. The rate of temperature rise, target temperature, application time, and power of MW affects the decomposition of landfill leachate. Studies indicated that the combination of MW radiation with other methods enhanced the decomposition of organic matter in the leachate. Formation of strong free radical in the Advanced Oxidation Processes (AOPs) process ensures effective and powerful dissolution of organic substances in the leachate. The hybrid MW-PS (persulphate) process is seen as an applicable method for the treatment of landfill leachate, considering the leachate volume and pollutant removal rate. In this review study, the MW process applied in the treatment of leachate generated in the landfill area was examined in terms of power consumption, efficiency, and operating cost. In addition, more effective and efficient combined MW/AOPs processes in the leachate treatment were also evaluated.

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