Different Approaches for the Separation of Suspended Solids in Aquaculture System

• Published in: Journal of Water and Environment Technology Vol. 11; no. 2; pp. 59 - 70
• Main Authors: ERMUKDAKUL, Thanakorn, CHAWALOESPHONSIYA, Nattawin, BOONCHAYAANANT, Benjaporn, PUNGRASMI, Wiboonluk, PAINMANAKUL, Pisut
• Format: Journal Article
• Language: English
• Published: Tokyo Japan Society on Water Environment 2013; Japan Science and Technology Agency
• Subjects: aquaculture system; coagulation, filtration; sedimentation; separation; suspended solids
• ISSN: 1348-2165; 1348-2165
• DOI: 10.2965/jwet.2013.59

The objective of this research is to propose the suitable suspended solid (SS) treatment process for the wastewater of the actual aquaculture systems (tilapia ponds). Sedimentation, coagulation, and depth filtration were chosen and applied in this study. Sand and anthracite were used as media in the depth filtration; while alum was used as a coagulant in jar tests. The results showed that, at the optimal operating condition, sedimentation (overflow rate of 0.8 m/hr) and coagulation (alum concentration of 15 mg/L) can provide treatment efficiencies of 90% and 99.25%, respectively. However, several drawbacks (high detention time, decrease of pH value, sludge generation) were observed. Therefore, the depth filtration processes with single and dual media were applied at different media configurations. The highest treatment efficiency (92%) and moderate filtration performance (80 minutes operating time and 12 m/hr filtration rate) can be obtained with the combination of media between anthracite (2 mm effective size and 0.15 m in depth) and sand (0.8 mm effective size and 0.55 m in depth). Finally, sedimentation as pretreatment and aeration in batch mode along the media depth were proven to significantly enhance the overall filtration performance.