METHOD FOR DETERMINING CHEMICAL FEEDING RATE OF COAGULATING AGENT AND CHEMICAL FEEDING CONTROLLER

摘要

PROBLEM TO BE SOLVED: To perform efficient COD removal by adding both of an inorganic coagulating agent and organic coagulating agent at the optimum amounts of addition meeting the target treatment value for COD removal, i.e., in the state optimum on both of a treatment cost and treatment efficiency regardless of the daily fluctuation in the quality of waste water in waste water treatment to obtain treated water by separation of solid from the liquid after adding the inorganic coagulating agent and the organic coagulating agent to the COD- containing waste water. SOLUTION: This method for determining the chemical feeding rate consists in setting the suspended solid concentration corresponding to the CODMN concentration of the treated water which is the target from the relation between the CODMN concentration and suspended solid concentration of the treated water of the waste water previously determined by a jar test and determining the required amounts of addition of the inorganic coagulating agent and/or the organic coagulating agent in such a manner that the suspended solid concentration of the treated water obtained by the waste water treatment attains this set value of the suspended solid concentration. The chemical feeding controller controls the amounts of addition of at least one of the inorganic coagulating agent and/or the organic coagulating agent in accordance with the necessary amounts of addition determined by this method.