| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a coagulant injection control system which can further shorten a time delay of feedback correction, is applicable even when raw water is highly turbid, and can calculate a proper coagulant injection rate. <P>SOLUTION: The coagulant injection control system of a water purification plant, provided with a flock forming pond to which a coagulant is injected into the raw water to form flocks, and a sedimentation basin and a filter basin where the flocks are separated and removed, includes: a raw water sensor for measuring at least the turbidity of the raw water; a sampling part for collecting coagulant injection water obtained by injecting the coagulant into the raw water; an aluminum measuring device for measuring the concentration of aluminum contained in the collected coagulant injection water; an injection ratio calculation function for calculating a basic coagulant injection rate, using the measurement of the turbidity by the raw water sensor; a first correction value calculation function for calculating the correction value of the coagulant injection rate from the measurement of the aluminum concentration and a target value; and an injection ratio correction function for deciding a coagulant injection rate as the sum of the calculated basic coagulant injection rate and a first correction value. <P>COPYRIGHT: (C)2012,JPO&INPIT |
