| Today ,waste water treatment and reuse usually using advanced treatment to clean waste water and then reusing them to cooling circulation water system, which needs to consume a large amount of energy and is very expensive and contributes a big economic burden to factories. In this study a tentative of utilizing industrial waste water to replenish circulating water system was advanced for to find economical and rational methods of energy conservation and discharge contraction. Biochemical, erosive and encrusted behavior of cooling circulation water system added in industrial wastewater and the corresponding means were approached. The rates of bacterial growth, corrosion and encrustment were all obvious increasing when waste water was added into the cooling circulation water system. It was dangerous that direct put waste water into circulation. For example, the bacterial population was 7．5 times the amount of what it had been a day before in the simulative cooling water which was added in 5% waste water, while the number was 21．7 times in 4 days, and the corrosion rate to carbon steel rised to 2．825mm/a. A lot of germicidal agents were researched and found them could perform the action of disinfection and algae removal, but needed a big use level and only maintained a short time. As a result, electrodes of oxidation resistant steel and a device of electrochemical disinfection and algae removal were created and structural and running parameter was optimized. Electrochemical oxidationg the simulative cooling water which contained waste water, the result showed that the device behaved effectively disinfection and algae removal: when the voltage was 3V and oxidized 30min, the rate of disinfection was 99．99%; oxidized 60min, there was not any bacteria in the water in a month. Besides, electrochemical oxidization could decrease COD, turbidity, colourity and heavy metal ions of the water. General reagents of cooling water treatment had a bad behavior to protect carbon steel in cooling water which contained waste water, so prepared a novel special inhibitor. In the pH=6．5～8．0 cooling water contained industrial waste, corrosion rate could decrease to 0．062 mm/a by put in the inhibitor, which was below 0．125 mm/a of the national standard. In the experimental process, a compromising analytical accuracy of COD determination method in possession was generated from the lowest to the highest concentration of COD to calculate the COD of a solution was found. A new method of spectrophotometric and multi-linear analysis of COD is described, which was a accurate, convenient and fast method, and the time that spent on the reflux was shorten from 2 h to 45 min.
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