Evaluation on the Availability of Treated Sewage Water as an Unused Energy Source in a Super High-rise Complex Building

Because the super high-rise complex building would be designed vertically with a mixed-use space, a large amount of unpurified domestic sewage could be discharged continuously outside the building site. The waste heat from the sewage water can be used for low temperature heating and high temperature cooling sources for HVAC system such as radiant heating and cooling system, and domestic hot water services. This study aims to evaluate the availability of treated sewage water as an unused energy source in a super high-rise complex building. For this purpose, current sewage treatment methods were analyzed to clarify the alternatives of heat source, and thermal energy potentials were evaluated according to the quantity of treated water and seasonal temperature variation. In conclusion, it was forecasted that the treated sewage water could be more effective for using the heating sources rather than the cooling sources because the temperature differences in spring and winter between treated sewage water and outdoor air was larger than those in summer. Also the thermal energy potentials were estimated from 20,900 MJ/day to 62,700 MJ/day according to the building use patterns.