| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a chemical injection device which injects a chemical such as a sterilizing agent with reduced concentration unevenness, and a water-feeding unit. <P>SOLUTION: The chemical injection device includes a flow rate-detecting means for detecting a flow rate in a water pipe, an injection pump for injecting the chemical, and a control means for operating the injection pump according to the flow rate. If a calculated operating frequency of the injection pump is not less than a lower limit, then the injection pump is operated with the calculated operating frequency. If the operating frequency is less than the lower limit, then the injection pump is operated with a predetermined minimum frequency. The water-feeding unit has the chemical injection device, a water-feeding pump, a filtrating device, and the like. The water pipe is provided with the filtrating device disposed downstream of an injection position of the chemical injection device. The chemical is such a chemical as sterilizes and oxidizes raw water. <P>COPYRIGHT: (C)2012,JPO&INPIT |
