Blackwater biomethane recovery using a thermophilic upflow anaerobic sludge blanket reactor: Impacts of effluent recirculation on reactor performance

2020 ◽  
Vol 274 ◽  
pp. 111157 ◽  
Author(s):  
Lei Zhang ◽  
Bing Guo ◽  
Anqi Mou ◽  
Ran Li ◽  
Yang Liu
Keyword(s):  
Upflow Anaerobic Sludge Blanket ◽  
Anaerobic Sludge ◽  
Reactor Performance ◽  
Effluent Recirculation ◽  
Anaerobic Sludge Blanket

The periodic anaerobic baffled reactor

1998 ◽  
Vol 38 (8-9) ◽  
pp. 401-408 ◽  
Author(s):  
I. V. Skiadas ◽  
G. Lyberatos
Keyword(s):  
Upflow Anaerobic Sludge Blanket ◽  
Anaerobic Sludge ◽  
Switching Frequency ◽  
Reactor Performance ◽  
Active Biomass ◽  
Anaerobic Baffled Reactor ◽  
Stable Periodic ◽  
Reactor Type ◽  
Continuously Stirred Tank Reactor ◽  
Anaerobic Sludge Blanket

The most common bioreactor type used for anaerobic digestion is the Continuously Stirred Tank Reactor (CSTR). The main problem of this reactor type, i.e. the fact that the active biomass is continuously removed from the system leading to long retention times, has been overcome in a number of systems based on immobilization of the active biomass. Two represenstative types are the Upflow Anaerobic Sludge Blanket Reactor (UASBR) and the Anaerobic Baffled Reactor (ABR). The success of these reactor systems rests on the highly flocculated, well settling, compact methanogenic sludge granules which develop in these reactors. A novel reactor type named Periodic Anaerobic Baffled Reactor (PABR) has been designed, offering the following major advantage: it may be operated as an ABR, a UASBR or at an intermediate mode. The PABR hydraulic behavior has been characterized using residence time distribution experiments at different retention times. Simulating the PABR behavior, the dependence of the reactor performance on the switching frequency is determined as a function of the retention time. In particular, it is found that for high retention times the ABR mode is superior, whereas for low retention times, the UASBR mode should be preferred. In order to establish the accuracy of the predictions of the simulation study, the PABR behavior was experimentally verified using three different stable periodic states.

scholarly journals Design optimization of a simple, single family, anaerobic sewage treatment system

2017 ◽  
Vol 12 (1) ◽  
pp. 55-71
Author(s):  
Silvânia Lucas dos Santos ◽  
João Paulo de Oliveira Simões ◽  
Francisco Vieira Paiva ◽  
Adrianus van Haandel
Keyword(s):  
Large Scale ◽  
Sewage Treatment ◽  
Upflow Anaerobic Sludge Blanket ◽  
Septic Tank ◽  
Anaerobic Sludge ◽  
Single Family ◽  
Reactor Performance ◽  
Methanogenic Activity ◽  
Anaerobic Sludge Blanket ◽  
High Degree

Anaerobic sewage treatment systems, notably the upflow anaerobic sludge blanket reactor, have been applied successfully in Brazil in dozens of large scale units. In this paper a small reactor is proposed for use in single family houses, without a connection to a sewerage network. The proposed reactor is much smaller than the traditional septic tank and yet the treatment efficiency is much higher. It comprises a lower cylindrical digestion zone and an upper settling zone, connected by a transition zone. Several configurations with different digestion and settling zone diameters were tested to establish their influence on reactor performance. A high degree of organic matter removal was obtained with 250 L reactors with retention times of 6 to 12 hours. A large sludge mass was retained in the digestion zone and high treatment capacity was maintained throughout the study. Tests showed that sludge settled better in the reactor than it did after discharge with the effluent. In contrast the, methanogenic activity of the sludge in the reactor was the same as that of the sludge expelled.

scholarly journals Microbial dynamics in upflow anaerobic sludge blanket (UASB) bioreactor granules in response to short-term changes in substrate feed

Microbiology ◽  
2010 ◽  
Vol 156 (8) ◽  
pp. 2418-2427 ◽  
Author(s):  
William P. Kovacik ◽  
Johannes C. M. Scholten ◽  
David Culley ◽  
Robert Hickey ◽  
Weiwen Zhang ◽  
...  
Keyword(s):  
Phase 1 ◽  
Community Diversity ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Reactor Performance ◽  
Microbial Dynamics ◽  
Short Term ◽  
Clone Libraries ◽  
Anaerobic Sludge Blanket

The upflow anaerobic sludge blanket (UASB) reactor is a microcosm for the methanogenic degradation of organic matter in anaerobic environments, and depends on the auto-formation of dense 3D biofilms of 1–3 mm in diameter, referred to as granular sludge (biogranules). Past research has shown that UASB and other methanogenic reactors are extremely stable functionally, but the underlying basis of the functional stability is not well understood. In this study, microbial dynamics in the communities residing in UASB biogranules were analysed to determine responses to short-term perturbations (change in reactor feed). The reactor was fed with simulated brewery wastewater (SBWW) for 1.5 months (phase 1), acetate/sulfate for 2 months (phase 2), acetate alone for 3 months (phase 3) and then a return to SBWW for 2 months (phase 4). Analysis of 16S rRNA, methanogen-associated mcrA and sulfate reducer-associated dsrAB gene-based-clone libraries showed a relatively simple community composed mainly of the methanogenic archaea (Methanobacterium and Methanosaeta), members of the green non-sulfur (Chloroflexi) group of bacteria and Syntrophobacter, Spirochaeta, Acidobacteria and Cytophaga-related bacterial sequences. The mcrA clone libraries were dominated throughout by Methanobacterium- and Methanospirillum-related sequences. Although the reactor performance remained relatively stable throughout the experiment, community diversity levels generally decreased for all libraries in response to a change from SBWW to acetate alone feed. There was a large transitory increase noted in 16S diversity at the 2 month sampling on acetate alone, entirely related to an increase in bacterial diversity. Upon return to SBWW conditions in phase 4, all diversity measures returned to near phase 1 levels. Our results demonstrated that microbial communities, even highly structured ones such as in UASB biogranules, are very capable of responding to rapid and major changes in their environment.

Herbal pharmaceutical wastewater treatment by a pilot scale upflow anaerobic sludge blanket (UASB) reactor

2009 ◽  
Vol 59 (11) ◽  
pp. 2265-2272 ◽  
Author(s):  
S. Satyanarayan ◽  
A. Karambe ◽  
A. P. Vanerkar
Keyword(s):  
Biogas Production ◽  
Oxygen Demand ◽  
High Strength ◽  
Cost Effective ◽  
Pilot Scale ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Reactor Performance ◽  
Anaerobic Sludge Blanket

Herbal pharmaceutical industry has grown tremendously in the last few decades. As such, literature on the treatment of this wastewater is scarce. Water pollution control problems in the developing countries need to be solved through application of cost effective aerobic/anaerobic biological systems. One such system—the upflow anaerobic sludge blanket (UASB) process which is known to be cost effective and where by-product recovery was also feasible was applied for treatment of a high strength wastewater for a period of six months in a pilot scale upflow anaerobic sludge blanket (UASB) reactor with a capacity of 27.44 m3. Studies were carried out at various organic loading rates varying between 6.26 and 10.33 kg COD/m3/day and hydraulic retention time (HRT) fluctuating between 33 and 43 hours. This resulted in chemical oxygen demand (COD), biochemical oxygen demand (BOD) and suspended solids (SS) removal in the range of 86.2%–91.6%, 90.0%–95.2% and 62.6%–68.0% respectively. The biogas production varied between 0.32–0.47 m3/kg COD added. Sludge from different heights of UASB reactor was collected and subjected to scanning electron microscopy (SEM). The results indicated good granulation with efficient UASB reactor performance.

Impact of ozone pre-treatment on the performance of upflow anaerobic sludge blanket treating pre-treated grain distillery wastewater

2014 ◽  
Vol 70 (10) ◽  
pp. 1702-1708 ◽  
Author(s):  
L. Robertson ◽  
T. J. Britz ◽  
G. O. Sigge
Keyword(s):  
Unsaturated Fatty Acids ◽  
Oxygen Demand ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Reactor Performance ◽  
Distillery Wastewater ◽  
Pre Treatment ◽  
Anaerobic Sludge Blanket ◽  
Performance Results

Two 2 L laboratory-scale upflow anaerobic sludge blanket (UASB) reactors were operated for 277 days. The substrate of the control reactor (Rc) contained grain distillery wastewater (GDWW) that had undergone coagulant pre-treatment, and the substrate of the second UASB reactor consisted of GDWW that had undergone coagulant pre-treatment and ozone pre-treatment (Ro). Both reactors treated pre-treated GDWW successfully at ca. 9 kgCOD m−3 d−1. Chemical oxygen demand (COD) reductions of ca. 96% for Rc and 93% for Ro were achieved. Fats, oils and grease (FOG) reductions (%) showed variations throughout the study, and reductions of ca. 88 and 92% were achieved for Rc and Ro, respectively. Rc produced more biogas, and the methane percentage was similar in both reactors. UASB granule washout in Rc suggested possible toxicity of unsaturated fatty acids present in non-ozonated substrate. The feasibility of FOG removal was demonstrated as both reactors successfully treated pre-treated GDWW. Better results were obtained for Ro effluent during post-ozonation. The ozone pre-treatment possibly led to easier degradable wastewater, and better results could potentially be obtained when other post-treatment steps are applied. Ozone pre-treatment did not, however, show an added benefit in the reactor performance results.

scholarly journals Degradation of phenol and p-cresol in reactors

2000 ◽  
Vol 42 (5-6) ◽  
pp. 237-244 ◽  
Author(s):  
Herbert H.P. Fang ◽  
Gong-Ming Zhou
Keyword(s):  
Removal Efficiency ◽  
Retention Time ◽  
Hydraulic Retention Time ◽  
Phenol Concentration ◽  
Upflow Anaerobic Sludge Blanket ◽  
Anaerobic Sludge ◽  
Effluent Recirculation ◽  
Anaerobic Sludge Blanket

The effects of hydraulic retention time (HRT) and phenol concentration on the degradation of phenol and p-cresol in wastewater were investigated in two respective UASB (upflow anaerobic sludge blanket) reactors with effluent recirculation at 37 °C for over 440 days. After acclimation, nearly all the phenol and p-cresol at moderate concentrations could be degraded without carbohydrate as a co-substrate. Treating a wastewater containing 800 mg/l of phenol and 300 mg/l of p-cresol at HRT ranging 2–12 hours, the first reactor consistently removed 95% of phenol, 65% of p-cresol and 85% of COD at 8–12 hours of HRT; the efficiency, however, decreased at lower HRT. Treating wastewater containing a constant p-cresol concentration of 400 mg/l at 24 hours of HRT, the second reactor was able to remove 75–80% of COD when the phenol was 1200 and 1500 mg/l; the removal efficiency decreased as phenol concentration further increased. High levels of residual phenol and p-cresol in the effluent suppressed the activity of biogranules. The suppression of bioactivity was not permanent. Biomass was able to regain its activity fully after lowering the phenolic concentrations in the wastewater.

Removal of chlorinated phenols in upflow anaerobic sludge blanket reactors

1998 ◽  
Vol 38 (8-9) ◽  
pp. 359-367 ◽  
Author(s):  
Ronald L. Droste ◽  
Kevin J. Kennedy ◽  
Jingua Lu ◽  
Mercedes Lentz
Keyword(s):  
Acetic Acid ◽  
Upflow Anaerobic Sludge Blanket ◽  
Synthetic Wastewater ◽  
Anaerobic Sludge ◽  
Chlorinated Phenols ◽  
Reactor Performance ◽  
Chlorine Atoms ◽  
Toxic Agents ◽  
Anaerobic Sludge Blanket ◽  
Uasb Reactors

The dechlorination of chlorophenol (CP) compounds was investigated using upflow anaerobic sludge blanket reactors. A total of five trichlorophenols (TCPs) and a single dichlorophenol (DCP) were individually treated: 2,3,4-TCP; 2,3,5-TCP; 2,3,6-TCP; 2,4,5-TCP; 2,4,6-TCP; and 3,5-DCP. Synthetic wastewater composed of sucrose and acetic acid provided an alternate, readily biodegradable carbon source. Each chlorinated compound was concurrently fed to separate reactors. The parameters that were quantified include biogas composition, acetic acid concentration, COD, and VSS. The degree to which CPs were sorbed to the granular biomass in actively dechlorinating UASB reactors was found to be insignificant. CP compounds were able to be metabolized to mineral end products to a large extent at loadings where reactor performance was not impaired. Ortho chlorine atoms were most readily removed from CPs. CPs containing chlorine atoms in the para position were the most toxic agents with 2,4,5-TCP being the most toxic compound. Toxicity was reversible.

Pemodelan Reaktor Hibrid Anaerob Pengolah Molasse Pada Pembebanan Organik Tinggi

2020 ◽  
Author(s):  
Gede H Cahyana
Keyword(s):  
Fluidized Bed ◽  
Fixed Bed ◽  
High Rate ◽  
Upflow Anaerobic Sludge Blanket ◽  
Anaerobic Sludge ◽  
Expanded Bed ◽  
Anaerobic Sludge Blanket

Telah dikembangkan reaktor anaerob kecepatan tinggi (high rate) yang merupakan modifikasi reaktor konvensional. Di antaranya berupa (bio)reaktor pertumbuhan tersuspensi (contoh: UASB, Upflow Anaerobic Sludge Blanket) dan reaktor pertumbuhan lekat (Fixed Bed atau Biofilter, Fluidized Bed, Expanded Bed, Rotating Biodisc dan Baffled Reactor). Kedua tipe reaktor di atas memiliki sejumlah kelebihan dan kekurangan. Untuk mengoptimalkan nilai positifnya (terutama untuk keperluan desain) maka reaktor tersebut, pada penelitian ini, disusun menjadi satu urutan yang disebut Reaktor Hibrid Anaerob (Rehan) yakni UASB di bawah dan AF di atasnya. Lebih lanjut, penelitian ini diharapkan dapat memberikan informasi tentang kinerja Rehan dalam mengolah air limbah (substrat) yang konsentrasi zat organiknya (COD) sangat tinggi dan suatu model matematika yang dapat mewakili reaktor tersebut.

The treatment of iron oxalate leach liquors in a UASB with sulfate reduction

1997 ◽  
Vol 36 (6-7) ◽  
pp. 383-390 ◽  
Author(s):  
J. E. Teer ◽  
D. J. Leak ◽  
A. W. L. Dudeney ◽  
A. Narayanan ◽  
D. C. Stuckey
Keyword(s):  
Bacterial Species ◽  
Upflow Anaerobic Sludge Blanket ◽  
Anaerobic Sludge ◽  
Desulfovibrio Vulgaris ◽  
Hydrogenotrophic Methanogenesis ◽  
Irreversible Effects ◽  
High Concentrations ◽  
A Minor ◽  
Anaerobic Sludge Blanket ◽  
Reducing Bacteria

The presence of small amounts of iron (>0.013% Fe) in sand creates problems in the manufacture of high quality glass. Removal by hot sulphuric acid is possible, but creates environmental problems, and is costly. Hence organic acids such as oxalic have been investigated since they are effective in removing iron, and can be degraded anaerobically. The aim of this work was to identify key intermediates in the anaerobic degradation of oxalate in an upflow anaerobic sludge blanket reactor (UASB) which was removing iron from solution in the sulphide form, and to determine the bacterial species involved. 2-bromoethanesulfonic acid (BES) and molybdenum were selected as suitable inhibitors for methanogenic and sulphate reducing bacteria (SRB) respectively. 40mM molybdenum was used to inhibit the SRB in a reactor with a 12hr HRT. Total SRB inhibition took place in 20 hrs, with a complete breakthrough of influent sulphate. The lack of an immediate oxalate breakthrough confirmed Desulfovibrio vulgaris subspecies oxamicus was not the predominant oxalate utilising species. Nevertheless, high concentrations of molybdenum were found to inhibit oxalate utilising bacteria in granular reactors but not in suspended population reactors; this observation was puzzling, and at present cannot be explained. Based on the intermediates identified, it was postulated that oxalate was degraded to formate by an oxalate utilising bacteria such as Oxalobacter formigenes, and the formate used by the SRBs to reduce sulphate. Acetate, as a minor intermediate, existed primarily as a source of cell carbon for oxalate utilising bacteria. Methanogenic inhibition identified that 62% of the CH4 in the reactor operated at 37°C originated from hydrogenotrophic methanogenesis, whilst this figure was 80% at 20°C. Possible irreversible effects were recorded with hydrogenotrophic methanogens.

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