APPARATUS FOR TREATMENT OF SHIPS' BALLAST WATER

摘要

PURPOSE: A ballast water processing unit of a vessel is provided to produce a target chlorine density through the output of an electrolysis device automatically controlled at a rapid response time according to seawater influx flowed into the ballast without a separate seawater saline densitometer and chlorine densitometer when the target chlorine density is set. CONSTITUTION: A ballast water processing unit of a vessel comprises an electrolysis device which generates sodium hypochlorite by electrolyzing ballast water; an ammeter; a voltmeter; a flow meter(60); a control unit(10); a memory; and a target chlorine density input means. A database formed by accumulating the output voltage to the input voltage of the electrolysis device, and the electrolysis efficiency (the rate of an actual chlorine generation amount to a theoretical chlorine generation amount at an input current) is stored in the memory. The control unit computes seawater saline density with both end voltages of the electrolysis device measured at the voltmeter to the input current of the electrolysis device measured at the ammeter. The memory reads the electrolysis efficiency as a corresponding seawater saline density. Feedback compensation current which outputs an electrolysis volume reaching a target chlorine density at the seawater saline density and the seawater influx is computed by an equation: compensation current = (influx * target chlorine density * compensation constant)/electrolysis efficiency; and the feedback compensation current is output at the electrolysis device.