• Title/Summary/Keyword: eletrolysis

Search Result 4, Processing Time 0.023 seconds

Volume Reduction of Waste Water Sludge using Electrolysis (전기분해를 이용한 하수 슬러지 감량)

  • Lee, Byungheon;Bang, Myunghwan;Kim, Geonha
    • Journal of Korean Society on Water Environment
    • /
    • v.22 no.2
    • /
    • pp.264-270
    • /
    • 2006
  • In this research, volume reduction of activated sludge using electrolysis was studied to find an optimum condition using lab scale experiments. Wasted sludge was treated by electrolysis with controlling current density, chloride concentration, electrode distance, and reaction time. Volume of return sludge was reduced by 9.79% in average while maximum was 16.7%. Sludge volume reduction efficiency was affected by current density and reaction time. It was reversely proportional to the electrode distance. Especially current density was effective on the system performance significantly. Electric conductivity, salinity and COD were increased by electrolysis implying sludge disintegrated and converted to COD in part. An empirical equation for total solid removal efficiency by electrolysis was proposed by multiple linear regression analysis as: $TS_{rem}$(%) = 5.534 ${\times}$ current density (A/l) + 0.178 ${\times}$ reaction time (m) + 2.758.

Treatment of reactive dyes wastewater by electrochemical method (전기화학적인 방법에 의한 반응성 염료폐수의 처리)

  • Yu, Jae-Jeong;Jeon, Seong-Hwan;Park, Jeong-Min;Jeong, Jae-Ho;Park, Sang-Jeong;Min, Kyung-Sok
    • Journal of Korean Society on Water Environment
    • /
    • v.18 no.3
    • /
    • pp.245-251
    • /
    • 2002
  • Reactive dyes waste water, a toxic and refractory pollutant, was treated by an electrochemical method using $Ti/IrO_2$ as anode and Stainless Steel 316 as cathode. In this technique, sodium chloride as an electrolyte was added. A number of experiments were run in a batch system. Artificial samples (reactive blue 19, red 195, yellow 145) were used. Operation parameters, such as supporting electrolyte concentration, current density, pH and sample concentration have been investigated for their influences on COD and color removal efficiencies during electrolysis. After 5 and 90 minites of eletrolysis, color was reduced by 51.5% and 98.9% respectively. Under the condition of current density $10A/dm^2$, NaCl concentration 12mg/l and pH 3, 62.9% of $COD_{Cr}$ was removed after electrolysis for 90 minites. The optimum condition of color removal and COD reduction in this work was found to be the following : pH 3, sodium chloride concentration 20g/l, current density $10A/dm^2$. As a result, we confirmed to be effective to color removal and reduction of refractory organic material.

Characteristics of Copper-catalyzed Cyanide Decomposition by Electrolysis (전해법에 의한 구리함유 시안의 분해특성)

  • Lee Jin-Yeung;Yoon Ho-Sung;Kim Sung-Don;Kim Chul-Joo;Kim Joon-Soo;Han Choon;Oh Jong-Kee
    • Resources Recycling
    • /
    • v.13 no.1
    • /
    • pp.28-38
    • /
    • 2004
  • The characteristics of cyanide decomposition in aqueous phase by electric oxidization have been explored in an effort to develop a process to recycle waste water. Considering current efficiency and voltage, the free cyanide decomposition experiment by electric oxidization indicated that 5 V of voltage and copper catalytic Cu/CN mole ratio 0.05 was the most appropriate condition, where current efficiency was 26%, and decomposition speed was 5.6 mM/min. High voltage and excess copper addition increased decomposition speed a little bit but not current efficiency. The experiment of free cyanide density change proves that high density cyanide is preferred because speed and current efficiency increase with density. Also, the overall decomposition reaction could be represented by the first order with respcect to cyanide with the rate constant of $1.6∼7.3${\times}$10^{-3}$ $min^{-1}$ The mass transfer coefficient of electric oxidization of cyanide came out as $2.42${\times}$10^{-5}$ $min^{-1}$ Furthermore, the Damkohler number was calculated as 5.7 in case of 7 V and it was found that the mass transfer stage was the rate determining step.