Untreated Wastewater Heating and Cooling System Serves Community in Tokyo

The Koraku Pumping Station, managed by Tokyo's Bureau of Sewage, is equipped with the nation's first community heating and cooling system utilizing untreated wastewater at its environment-friendly wastewater treatment plant. The system serves an area of 21.6 hectares around the plant.

The plant contributes to environmental protection by taking advantage of the characteristics of wastewater temperature and not using fossil fuels. Because it efficiently recovers waste heat, it is also highly valued as a measure to counter the urban heat island effect.

Wastewater is stable in volume and its temperature is lower in summer and higher in winter than the air temperature. By using these characteristics through the medium of a heat pump, this system can reduce energy use by 40 percent, and emissions of nitrogen oxide and carbon oxide by 52 percent, and sulfur oxide by 65 percent. The system also effectively conserves water because it does not use water in a cooling tower.

The Bureau of Sewage has been using untreated wastewater for heating and cooling purposes at its 12 waste water treatment facilities across Tokyo since a building-based air conditioning system using sewage was first introduced at the Ochiai Wastewater Treatment Plant in January, 1987.



Posted: 2003/10/05 06:26:14 AM
Japanese version