Performance evaluation of an anaerobic hybrid reactor treating petrochemical effluent

Organic loading rate (OLR), Hydraulic Retention Time (HRT) and up flow velocity are important parameters significantly affecting microbial ecology and characteristics of anaerobic reactors. In this study, Performance of an anaerobic hybrid reactor (UASB/Filter) at mesophilic condition was evaluated in a 15.4 L reactor receiving petrochemical wastewater. The temperature of influent was adjusted by an inline heat exchanger at around 35 ˚C. The reactor was seeded with flocculent sludge from a UASB plant treating dairy wastewater. The sludge was acclimatized to petrochemical wastewater in twostage operation. After 39 weeks, a COD reduction of 70.3% was obtained at OLR=2.0 kg m-3 d-1 and HRT=18 h. Under steady state conditions, experiments were conducted at OLRs of between 0.5 and 24 kg TCOD m-3 d-1 , hydraulic retention times (HRT) of 4-48 h and up flow velocities 0.021-0.25 m h-1. Removal efficiencies in the range of 42-86% were achieved at feed TCOD concentrations of 1000- 4000 mg L-1 . The biogas production data used for determination of biogas production kinetics. The values of Gmax and GB estimated as 11.173 LL-1d -1 and 85.83 g L-1d -1 , respectively.

Thermophilic Anaerobic Digestion of Second Cheese Whey: Microbial Community Response to H2 Addition in a Partially Immobilized Anaerobic Hybrid Reactor

In this study, we investigated thermophilic (55 °C) anaerobic digestion (AD) performance and microbial community structure, before and after hydrogen addition, in a novel hybrid gas-stirred tank reactor (GSTR) implemented with a partial immobilization of the microbial community and fed with second cheese whey (SCW). The results showed that H2 addition led to a 25% increase in the methane production rate and to a decrease of 13% in the CH4 concentration as compared with the control. The recovery of methane content (56%) was reached by decreasing the H2 flow rate. The microbial community investigations were performed on effluent (EF) and on interstitial matrix (IM) inside the immobilized area. Before H2 addition, the Anaerobaculaceae (42%) and Lachnospiraceae (27%) families dominated among bacteria in the effluent, and the Thermodesulfobiaceae (32%) and Lachnospiraceae (30%) families dominated in the interstitial matrix. After H2 addition, microbial abundance showed an increase in the bacteria and archaea communities in the interstitial matrix. The Thermodesulfobiaceae family (29%)remained dominant in the interstitial matrix, suggesting its crucial role in the immobilized community and the SHA-31 family was enriched in both the effluent (36%) and the interstitial matrix (15%). The predominance of archaea Methanothermobacter thermoautrophicus indicated that CH4 was produced almost exclusively by the hydrogenotrophic pathway.

Kinerja Reaktor Hibrid Anaerob pada Kecepatan Tinggi dalam Mengolah Air Limbah Molasse

This research describes the performance of a laboratory scale anaerobic hybrid reactor (so called as Rehan) that combines an upflow anaerobic sludge blanket (UASB) in lower part and AF (anaerobic filter) filled with gravel or pebble in upper part of the reactor. It was operated at ambient temperature and high organic loading rate that varied from 8.26 to 34.05 g/l.day with average hydraulic retention time of 30 hours. The results showed that Rehan could achieve COD conversion of 50.19% to 79.34% with no sludge recirculation and 79.88% to 85.72% in mode of returned sludge. And so, a special phenomenon came up in the bottom of Rehan i.e. in suspended growth zone where the reduction of organic pollutant up to 65%. In this zone, the sludge concentration or volatile suspended solid was very high. But, when the organic loading about 40,000 mg/l COD, the performance of Rehan steeply came down, its efficiency became 50.19%. Nevertheless, in general, Rehan could treat the organic waste up to 25,000 mg/l COD.

An anaerobic hybrid bioreactor for biologically enhanced primary treatment of domestic wastewater under low temperatures

Anaerobic hybrid reactor system for the generation of methane-rich biogas and energy. An energy-positive alternative to conventional primary treatment of raw domestic wastewater.