Feasibility study on the treatment of algae bloom in ballast water by dielectric barrier discharge (DBD) process

This study evaluates the feasibility of treating algal bloom in ballast water by a Dielectric Barrier Discharge (DBD) process. The effects of the treatment on the concentration of chlorophyll a and the total organic carbon (TOC) contents were investigated. Cell morphology was used to support the experimental results. 8 algae cultures, as well as real algal bloom water from a fish farm were treated with the DBD system. Chlorophyll a and cell morphology studies indicated that the DBD system was effective in treating algal bloom as the reactive species generated attacked the cell wall of the culture causing cell disruption and mortality. The rate of reduction of chlorophyll a’s concentration decreases with concentration for both the commercial cultures and the real algae water. Therefore DBD system is applicable in treatment of algal bloom in ballast water. TOC analysis revealed that the cell disruption might release organic compound such as toxins that were residing within the cell which can pass through the filter with a pore size of 0.45µm. When the cell wall was disrupted, these organic contents or toxins were released into the solution leading to an increase in TOC with respect to time as observed. Besides attacking the cell wall of the remaining life cultures, the reactive species also oxidise these organic contents which leads to decrease in TOC at subsequent time. The change in TOC with respect to time varied with type of cultures.Bachelor of Engineering (Environmental Engineering