Optimizing the start-up phase for granular activated sludge using bio char / sludge char powder
No Thumbnail Available
Insinööritieteiden korkeakoulu | Master's thesis
Master's Programme in Water and Environmental Engineering (WAT)
AbstractAerobic Granular Sludge (AGS) technology emerged as sustainable technology for treatment of variable characteristic municipal and industrial wastewater. However, AGS granulation time and stability issues need investigation. In instant research, the enhancement of the AGS granulation was investigate using commercially available Bio char (BC) and sludge char (SC). Laboratory scale Sequence Batch Reactor (SBR) operated with 4-hour cyclic regime was used for start-up phase analysis of AGS granulation. The nucleating material (BC/SC) dosage of 1 g/L was introduced twice in the reactor for accelerating granulation of aerobic sludge. Experimental work proved the possibility of acceleration of granulation using nucleating material. Reactors operated with nucleating material showed granules in less than a week, the earliest granule was seen on 4th day. The porous property of BC and later high surface area of SC provided good sites for microbe adhesion and agglomeration. Microscopic examination of granulation on the 21st day showed BC and SC presence in the inner core of granules which provided site for microbial colonization. Good granular size range between 0.05-2 mm were seen in the start-up phase. The flaky structured granules were also seen which need further investigation. The nutrient removal efficiency of reactor operated with BC on day 72 showed removal of Chemical Oxygen Demand (COD) 80 %, Total Nitrogen (TN) 70%, and Total Phosphorus (TP) 20%. The results showed that granulation time can be improved by using SC and BC as nucleating material.
Thesis advisorAl-Juboori, Raed
aerobic granular sludge, sludge char, biochar, wastewater treatment