Treatability Study of Electro-aggregation For Dyestuff Wastewater

• Main Authors: Lee, Chung-Che, 李宗哲
• Other Authors: Sue-Huai Gau
• Format: Others
• Language: zh-TW
• Published: 1998
• Online Access: http://ndltd.ncl.edu.tw/handle/20037493729460603884

碩士 === 淡江大學 === 水資源及環境工程學系 === 86 === The Electro-aggregation Method is a relatively new technique being developed recently. By the theory of employing the function of external electric field induced, the electric charge of contaminates will generate the sequence rearrangement forcing them to collide with each other for mutual condensation, and further enlarge the diameter of particles, and to achieve the effect of removing the contaminates. Researches indicated that such kind of process could achieve obvious treatment effect for many kinds o The experiment of the research was conducted by using the raw wastewater that flowed into the equalization tank of a 500 CMD dyeing factory. The operative parameters included the layers of electro-chemical reaction tank, operational voltage, pH inflow, dilution times of inflow water, and the retention time. The influence of the operative parameters on the removing efficiency of the contaminants, were discussed included COD, ADMI (true color), chloride, and soluble iron. The results indicated that, the stability of electrical current conveyed from the 5-layer reaction tank were steadier than that of 4-layer ones. In aspect of 4-layer reaction tank, under 5 times of dilution, better COD removal was obtained by no adjusting pH, i.e. raw water, and at pH 4. The operational voltage and retention time, are two strongly connected factors that influence the quality of the treated water. In the case of 4-layer reaction tank with 5 times of raw water dilution, if the inflow pH is not adjusted and the duration of retention time is 630 seconds, the better COD removal could be obtained. When the voltage was set at 150 V, which may run up to 55 %. If reducing the retention time to 252 seconds, only 40 % of COD removal could be achieved. In aspect of ADMI decrease, be Concerning the dilution times for the sample water which was treated by 4-layer electro-chemical reaction tank, the maximum COD removing rate could only reach 50% when the sample water was not being diluted. When we diluting the sample water 5 times, under certain conditions, the COD removing rate could run up to 63%. To ADMI, almost no effect would act on ADMI decrease if not being diluted; and in the case of 5 times dilution, ADMI could be reduced to 500 under certain operational conditions. Concerning the 2nd treatment, no obvious elevation of treatment effect (approx. 40%; correlative to raw water) was seen in the absence of dilution for these two treatments. When being diluted 5 times after the first treatment for further treatment once again, then the COD removing rate could be enhanced to 67%(correlative to raw water). Concerning the power consumption, most effective power saving could be achieved for 5-layer electro-chemical reaction with similar or even better treatment result and such phenomenon was becoming more obvious along with higher voltage. Moreover, the dilution time is also one of the affection factors because it has affected the electric conductivity. When being diluted in 5 times and 3 times respectively with 337 seconds of stay time and voltage at 200 V, the power consumption was 3863 kW-hr and 6835 kW-h