1987 Volume 22 Issue 1 Pages 36-43
It was found from the observation of 0x/03 during past seven years at Shiogama Station that the decrease of sensitivity of an oxidant meter was caused by “fouling” on the countercurrent absorption tube, especially in summer. The authors found that bacteria existed in all the piping of oxidant meter, and taht the number of them was remarkably large in the countercurrent absorption tube. The authors examined the reactivity of iodine toward bacteria in the absorbing solution and found that bacteria removes iodine in the absorbing solution. And it was found that the concentration of iodine in the absorption solution was decreased in inverse proportion to the quantity of bacteria. A considerably large quantity of iodine is decreased even by the reaction of iodine with bacteria at 0°C within ten minutes. These results indicated that the decrease of measured value of oxidants is caused by bacteria.
