To prevent decomposition of a formable chemical liquid such as a sodium hypochlorite aq. soln. by supplying a chemical liquid from a reservoir tank of the chemical liquid through a transporting pipe under pressure to pass through a pressure controlling valve and injecting the passed chemical liquid to city water near the water distribution port.
The city water treating facility is composed of a controlling building 11 and a treating pond 12. The chemical liquid is supplied from a reservoir tank 14 of the chemical liquid in or near the controlling building 11 through a transporting pipe 19 under pressure by using a weighing pump 15 which acts by a diaphragm method, electromagnetic method, ultrasonic method or the like. The chemical liquid supplied under pressure is injected to the city water through a chemical liquid injecting port near the city water distribution port 21 of a treating pond 12. The transporting pipe 19 is equipped with a pressure controlling valve 22 so as to control the pressure of the chemical liquid when the liquid is injected from the chemical liquid injecting part 20. Thereby, decomposition of a foaming chemical liquid such as a sodium hypochlorite aq. soln. can be prevented, and controlling property for injection of a foaming chemical liquid can be improved.
FUJIMOTO HIROSHI
SHIBAURA OSAMU
TANI TATATOMI
MITSUI CHEMICALS INC