Evaluating the application ability of membrane-less microbial fuel cells in shrimp farming wastewater recirculation

Abstract

Microbial fuel cell (MFC) was considerable as a promising saline wastewater treatment which using microorganism to convert organic compounds to electrical energy. Most of wastewater generated from aquaculture farming contained highly saline effluents. In addition, the maintenance of good water quality was essential for optimum growth and survival of shrimp. This study aimed to evaluate the ability of Membrane-less Microbial Fuel Cells (MFCs) to treat wastewater for recirculation of shrimp culture wastewater, and improvement in the growth performance of Penaeus vannamei (White Leg Shrimp). Six MFCs models were built with locally available materials such as: polyvinyl chloride (PVC), anaerobic sludge, carbon cloth anode and cathode electrodes, granular graphite, glass wool and glass bead. This study compared two different treatments including: control (cultivation with no MFCs models) and MFCs models (application models with shrimp culture), run in continuous mode at room temperature (25⁰C – 30^oC). Each treatment was run in triplicate with shrimp at size PL₃₀-PL₄₅, average initial weight of 0.91 +/- 0 (g) and average initial length of 3.03 +/- 0.6 (cm). Experiments were set up using the 120 L tanks (working volume of 90 L), input with seawater at 20 ppt salinity, temperatures range of 22â—¦C to 26â—¦C, pH range of 7.5 to 9.4, and dissolve oxygen range of 5.5 to 7.2. The density of shrimp was 5 post larvae (PL) per liter. Research results achieved the removal of chemical oxygen demand, ammonia, nitrite and nitrate were up to 58.83%, 76.1%, 56.33% and 70.90%, respectively. The survival rate of shrimp was maintained, and growth rate was enhanced significantly compared with control treatment. The obtained results in this study presented that MFCs has ability to treat pre-circulation of shrimp culture wastewater and improved in the growth performance of Penaeus vannamei (White Leg Shrimp).