Abstract: The present invention provides a system that utilizes microwave heating to sterilize contaminated effluent. The system sterilizes the contaminated effluent by heating it to a minimum temperature for a minimum duration under pressure, and then discharging it to a sanitary drain as sterilized effluent. The process maximizes energy efficiency by using a heat exchanger to raise the temperature of the contaminated effluent with heat drawn from the sterilized effluent of the previous batch. All solids and particles originally present in the contaminated effluent pass through the system and are discharged as part of the sterilized effluent.