Comparative Study of Different Media in the Treatment of Sago Wastewater using HUASB Reactor

摘要

Processing of sago generates enormous quantities of high strength wastewater requiring systematictreatment prior to disposal. The present study is an attempt to compare the three media such aspolypropylene ring, rosette filter and PVC carrier, in the treatment of sago wastewater using HybridUpflow Anaerobic Sludge Blanket (HUASB) reactor. Three HUASB reactors each with a volume ofabout 4.7 L and effective volume of 4.2 L was operated and packed with the above three mediaseparately in each reactor along with the effective microorganisms (EM) solution added in 1:1000 ratioof reactor volume. The initial OLR (Organic Loading Rate) range was about 0.75 kg.COD/m3.day andfurther increased. Various effluent characteristics like pH, COD, total suspended solids (TSS), VFA,alkalinity and biogas production were studied until the attainment of steady state. The pH of treatedeffluent during steady state condition was almost neutral for all the three reactors even though theinfluent had an acidic pH. The optimum HRT was found to be 10h for both polypropylene media andPVC carrier media and 8h for rosette filter media. The maximum COD and TSS removal efficiencies forthe reactor packed with polypropylene were as high as 88% and 77% in HUASB reactor in thepresence of effective microorganisms with an OLR of 9 kg.COD/m3.day. And for the reactor packedwith rosette filter, the maximum COD and TSS removal efficiencies were 84% and 76% in HUASBreactor in the presence of effective microorganisms with an OLR of 9 kg.COD/m3.day. Similarly, for thereactor packed with PVC carrier media, the maximum COD and TSS removal efficiencies were 86%and 78% in HUASB reactor in the presence of effective microorganisms with an OLR of 9 kg.COD/m3.day. The maximum gas production for these three reactors packed with polypropylene ring, rosettefilter and PVC carrier media were 2.8 L/d, 0.66 L/d and 1.7 L/d respectively in the presence of effectivemicroorganisms. It is found that from an overall assessment, the HUASB reactor packed withpolypropylene ring has proved superior in its performance compared to the HUASB reactor with otherpacking media.