Wastewater utilization system and wastewater utilization method

摘要

PROBLEM TO BE SOLVED: To provide a drainage water utilization technique capable of obtaining hot water, for a desired purpose such as cleaning water, from drainage water with improved resource and energy saving performance.SOLUTION: A drainage utilization system 1 comprises: a UF membrane treatment system 11 to produce treat water through purification treatment of drainage water; a heat recovering heat exchanger 13 to increase a temperature of the treat water through heat exchange between the treat water and cooling water which flows into the heat exchanger with the temperature thereof higher than the treat water and is circulated between a cooling tower 32 and a cooling machine 31 in an air-conditioning system 3 which has the cooling machine 31 supplying and circulating cold water for air-conditioning by receiving a supply of cooling water from the cooling tower 32; and a heat recovering heat pump 14 to further increase the temperature of the treat water flowing therein with the temperature thereof increased by the heat recovering heat exchanger 13 after the treat water absorbs heat from the water returned to the cooling machine 31 of the air-conditioning system 3 and to supply the treat water with the temperature thereof increased to a hot water utilizing facility 4.