Improvement of Cooling Water Recirculating System and the Effect on Life Extension of Heat Exchanger Tubes
Hiroyasu MATSUDA, Masaru YOSHIDA and Yoshito KATSURA
Abstract:To reduce the corrosion by MIC(Microbiologically Influenced Corrosion) of the heat exchanger's carbon steel tubes in Mitsui Chemicals Osaka Factory(MCI Osaka),we improved the circulating cooling water systems. Furthermore we studied the ability of several kinds of inhibitors used in our water cooling system. To reduce MIC potential,we have changed the sterilizing method,that is,from the intermittent addition of NaClO bactericide to the continuous one.As the result of it,life of the heat exchangers was prolonged above twice. Additionally,we studied the ion selective property of synthetic iron rust membranes (ƒÀ|FeOOH) absorbing the inhibitorCsuch as OP(OrthoPhosphoric acid)CPBTC(2PhosphnoButane-1,2,4-TriCarboxylic acid ), HEDP(HydorxyEthilidene-1,1-DiPhosphonic acid) ,PAA(PolyAcrylic Acid) and etc. Cation Selective was increased in the order :OP