dc.description.abstract | Petroleum has been the major energy resource and chemical raw material since the mid of 20th century and definitely related to the contemporary economical and civilization development. Meanwhile, increasing distillation, cracking and re-composition of refinery process has led large amount of wastewater generation in general, Refinery wastewater is high in SS and oil content. However, traditional wastewater treatment processes for refinery wastewater take large space and cost. Hence, finding a potential new approach for effectively treating refinery wastewater is very important.
Electro-aggregation and floatation(EAF) method is one of the new established wastewater treatment processes. Applying of electricity field to induce a dipolarization effect among the pollutants in wastewater is available in the EAF process. A patented special flow channel arrangement makes the become depolarized pollutants self-aggregation and forms larger flocks which can be further removed by floatation separation.
In this study a 250 CMD capacity module was setup to treat wastewater from the equalization tank of a refinery plant. The specific aim was to study the removal efficiency for SS, COD and oil by using a complete EAF plant. Total operational cost was also well evaluated.
Results showed that SS, COD and oil removal efficiency was 55.7%, 57.3% and 61.9%, respectively under low content of waste influent(average COD 801 mg/L), however, 96.0%, 84.6% and 80.0%, respectively, under high content of waste influent(average COD 33868 mg/L). In operation costs were 0.64NT$ for chemical used, 1.2NT$ for electricity consumption and 8.8NT$ for sludge treatment when low content of waste influent was treated, and 0.31NT$, 1.0NT$ and 26.2NT$, respectively, were needed for treating high content of waste influent. As a result of high oil removal efficiency, it is suggested that EFA method was a proper approach for treating high oil content refinery wastewater. | en_US |