Start-up of a thermophilic methanol-fed UASB reactor: change in sludge characteristics

2002 ◽  
Vol 45 (10) ◽  
pp. 145-150 ◽  
Author(s):  
P.L. Paulo ◽  
B. Jiang ◽  
K. Roest ◽  
J.B. van Lier ◽  
G. Lettinga
Keyword(s):  
Granular Sludge ◽  
Community Analysis ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Sludge Characteristics ◽  
Loading Rates ◽  
Start Up ◽  
Laboratory Scale Reactor ◽  
Methanol Removal ◽  
Scale Reactor

Experiments were performed to study the change in sludge characteristics and sludge granulation during the start-up of a thermophilic methanol-fed upflow anaerobic sludge bed (UASB) reactor. The laboratory scale reactor, was inoculated with thermophilic granular sludge and operated at 55°C over 130 days at organic loading rates (OLR) varying from 2.7 to 47 gCOD.L−1.d−1. Physical characterisation was performed for both the seed and the cultivated sludge. Results demonstrated that a good quality, well settleable granular sludge was cultivated and retained in the reactor, allowing an OLR of 47 gCOD.L−1.d−1 with 93% of methanol removal, where 79% was converted into methane. Using a community analysis of the cultivated consortia, high numbers of rod-shaped hydrogenotrophic methanogens were enumerated. Biomass washout coincided with a high specific gas load, but was not detrimental to the system in the conditions tested.

The effect of extreme temperatures (70–80°C) on the effluent quality and sludge characteristics of UASB reactors

1997 ◽  
Vol 36 (6-7) ◽  
pp. 325-332 ◽  
Author(s):  
Raghida Lepistö ◽  
Jukka Rintala
Keyword(s):  
Volatile Fatty Acids ◽  
Granular Sludge ◽  
Anaerobic Sludge ◽  
Methanogenic Activity ◽  
Sludge Characteristics ◽  
Effluent Quality ◽  
Start Up ◽  
Thermomechanical Pulping ◽  
Increasing Temperature ◽  
Uasb Reactors

The study focused on the effluent quality and sludge characteristics during the start-up and operation of extreme thermophilic (70 to 80°C) upflow anaerobic sludge bed (UASB) reactors, inoculated with mesophilic and thermophilic granular sludge and fed with acetate, volatile fatty acids (VFA), and thermomechanical pulping (TMP) whitewater. Low effluent quality and long start-up periods were observed during the start-up of the 70 to 76°C, VFA-fed UASB reactors inoculated with mesophilic granulae, while better effluent quality and considerably shorter start-up periods were observed when thermophilic (55/70°C) inocula were used. With VFA feed, a significant amount of acetate was removed at 70°C and even at 80°C, while propionate removal was negligible. With TMP whitewater feed, low VFA effluent concentration was obtained at 70°C. The volatile solids (VS) and the VS/total solids (TS) content of the sludge decreased significantly during the first 2–3 months of operation when mesophilic inocula were used. The initial specific methanogenic activity (ISMA) of the extreme thermophilic sludge decreased with increasing temperature and was slightly higher on glucose than on acetate. At 70 to 80°C, various rod-like bacteria were dispersed through the granulae in either individual or in low density micro colonies surrounded with a varying degree of precipitates.

Start up of Thermophilic UASB (Upflow Anaerobic Sludge Blanket) Reactors Using Micro-Carrier and Mesophilic Granular Sludge

1992 ◽  
Vol 26 (3-4) ◽  
pp. 877-886 ◽  
Author(s):  
T. Ohtsuki ◽  
M. Watanabe ◽  
Y. Miyaji
Keyword(s):  
High Performance ◽  
Ph Dependence ◽  
Granular Sludge ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Phase System ◽  
Two Phase ◽  
Start Up ◽  
Initial Seed

Two start-up methods of thermophilic UASB reactor were investigated for fast start-ups; one utilized micro-carrier as an initial support material and the other used intact mesophilic UASB granules as an initial seed. With both methods thermophilic granules having high activity were obtained in less than 3 months, even with acidified wastewater. Maximum sludge load for VFA substrate and sugar substrate were 3.2 and 0.9 kgCOD/kgVSS/day, respectively. Pre-acidogenesis was indispensable for high-performance treatment of sugar-containing substrate. It was proven that with a two-phase system sludge load could be raised to 3.0 kgCOD/kgVSS/day for sugar containing wastewaters. Some features of obtained sludge were examined, including maximum substrate utilizing activities, temperature dependence, pH dependence, and activity deterioration under lower loading conditions.

Start-up of a thermophilic upflow anaerobic sludge bed (UASB) reactor with mesophilic granular sludge

1992 ◽  
Vol 37 (1) ◽  
pp. 130-135 ◽  
Author(s):  
Jules B. van Lier ◽  
Katja C. F. Grolle ◽  
Alfons J. M. Stams ◽  
Everly Conway de Macario ◽  
Gatze Lettinga
Keyword(s):  
Granular Sludge ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Start Up

Removal of COD from Piggery Wastewater Using a Lab-Scale UASB Reactor

2012 ◽  
Vol 534 ◽  
pp. 221-224
Author(s):  
Fei Yan ◽  
Jin Long Zuo ◽  
Tian Lei Qiu ◽  
Xu Ming Wang
Keyword(s):  
Granular Sludge ◽  
Cod Removal ◽  
Upflow Anaerobic Sludge Blanket ◽  
Synthetic Wastewater ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Volume Loading ◽  
Piggery Wastewater ◽  
Start Up ◽  
Anaerobic Sludge Blanket

It took 55 days to start up a lab-scale upflow anaerobic sludge blanket (UASB) reactor at ambient temperature 27-28 oC by using the synthetic wastewater, and piggery wastewater was used as the influent after the reactor start-up. From day 120 onwards, COD removal efficiency maintained in the range of 85% to 95% with 6.79-9.66 kg COD/ (m3•d) of volume loading, and the effluent COD concentration ranged between 400 mg/L and 600 mg/L. Granular sludge formation was observed in the reactor after 40-day operation, and the sludge diameter reached 2-4 mm in the 120 day-old reactor. The pH changes in the influent had little influence on COD removal from piggery wastewater using the UASB reactor.

High-Rate Anaerobic Treatment of Industrial Wastewaters

1991 ◽  
Vol 24 (1) ◽  
pp. 69-74 ◽  
Author(s):  
J. Rintala
Keyword(s):  
Granular Sludge ◽  
Anaerobic Treatment ◽  
High Rate ◽  
Upflow Anaerobic Sludge Blanket ◽  
Synthetic Wastewater ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Industrial Wastewaters ◽  
Start Up ◽  
Uasb Reactors

Anaerobic mesophilic treatment of synthetic (a mixture of acetate and methanol) and thermomechanical pulping (TMP) wastewater was studied in laboratory-scale upflow anaerobic sludge blanket (UASB) reactors and filters with emphasis on the process start-up. The reactors were inoculated with nongranular sludge. The start-up of mesophilic and thermophilic processes inoculated with mesophilic granular sludge was investigated in UASB reactors fed with diluted vinasse. The start-up proceeded faster in the filters than in the UASB reactors with TMP and synthetic wastewater. Loading rates of over 15 kgCODm−3d−1 with 50-60 % COD removal efficiencies were achieved in 10 days in the mesophilic and in 50 days in the thermophilic UASB reactor treating vinasse. The results show that high-rate anaerobic treatment can be applied to different types of industrial wastewaters under varying conditions.

Optimal process pattern for simultaneous sulfur, nitrogen and carbon removal

2009 ◽  
Vol 59 (4) ◽  
pp. 833-837 ◽  
Author(s):  
Chuan Chen ◽  
Aijie Wang ◽  
Nanqi Ren ◽  
Xuliang Deng ◽  
Duu-Jong Lee
Keyword(s):  
Elemental Sulfur ◽  
Removal Rate ◽  
Granular Sludge ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Loading Rates ◽  
Process Pattern ◽  
High Removal Rate ◽  
Anaerobic Sludge Blanket

Denitrifying sulfide removal (DSR) process incorporates interactions between autotrophic and heterotrophic denitrifiers and reveals difficulty to achieve high removal rate of nitrogen and sulfur in practice. We compared the DSR performance of an expanded granular sludge bed (EGSB) reactor and an upflow anaerobic sludge blanket (UASB) reactor, both fed with wastewaters comprising sulfide, nitrate and acetate. The EGSB reactor can sustain at higher loading rates than UASB reactor, probably owing to the less elemental sulfur production rate for the latter in operation.

Pilot-scale thermophilic anaerobic treatment of wastewaters from seasonal vegetable processing industry

1997 ◽  
Vol 36 (2-3) ◽  
pp. 279-285 ◽  
Author(s):  
J. A. Rintala ◽  
S. S. Lepistö
Keyword(s):  
Pilot Study ◽  
Food Industry ◽  
Buffer Capacity ◽  
Granular Sludge ◽  
Pilot Scale ◽  
Anaerobic Treatment ◽  
Cod Removal ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Loading Rates

Thermophilic anaerobic treatment of food industry wastewaters was studied using a 0.65 m3 upflow anaerobic sludge bed (UASB) reactor. The reactor was operated at 55°C and placed on the premises of a factory manufacturing deep-frozen goods from vegetables. The hot (>80-90°C) and concentrated (COD 14-79 g/l) wastewater streams, deriving from steam peeling and blanching of carrot and potato were used. The UASB reactor was inoculated with a small amount of granular sludge from a full-scale mesophilic UASB reactor. Prior to inoculation, the inoculum was acclimated to 55°C for 2 days. The reactor was fed with a mixture of wastewaters diluted to the desired COD. The reactor was started with loading rates of about 1.2 kgCOD/m3d. After the initial acidification of the process, apparently due to insufficient buffer capacity, the COD removal started to improve and reached 60% within 35 days of inoculation. At the end of the 70 days run, more than 80% COD removal was achieved with loading rates of about 4 kgCOD/m3d. The pilot-study run was limited due to the end of the seasonal production in the target factory. The results of the pilot study together with the results from the intensive laboratory studies suggest the feasibility of thermophilic anaerobic treatment for the studied wastewaters.

Anaerobic Thermophilic (55°C) Treatment of TMP Whitewater in Reactors Based on Biomass Attachment and Entrapment

1999 ◽  
Vol 40 (11-12) ◽  
pp. 67-75 ◽  
Author(s):  
Sigrun J. Jahren ◽  
Jukka A. Rintala ◽  
Hallvard Ødegaard
Keyword(s):  
Granular Sludge ◽  
Biofilm Reactor ◽  
Upflow Anaerobic Sludge Blanket ◽  
Hybrid Reactor ◽  
Anaerobic Sludge ◽  
Loading Rates ◽  
Anaerobic Reactors ◽  
Multi Stage ◽  
Degradation Rates ◽  
Thermomechanical Pulping

Thermomechanical pulping (TMP) whitewater was treated in thermophilic (55°C) anaerobic laboratory-scale reactors using three different reactor configurations. In all reactors up to 70% COD removals were achieved. The anaerobic hybrid reactor, composed of an upflow anaerobic sludge blanket (UASB) and a filter, gave degradation rates up to 10 kg COD/m3d at loading rates of 15 kg COD/m3d and hydraulic retention time (HRT) of 3.1 hours. The anaerobic multi-stage reactor, consisting of three compartments, each packed with granular sludge and carrier elements, gave degradation rates up to 9 kg COD/m3d at loading rates of 15-16 kg COD/m3d, and HRT down to 2.6 hours. Clogging and short circuiting eventually became a problem in the multi-stage reactor, probably caused by too high packing of the carriers. The anaerobic moving bed biofilm reactor performed similar to the other reactors at loading rates below 1.4 kg COD/m3d, which was the highest loading rate applied. The use of carriers in the anaerobic reactors allowed short HRT with good treatment efficiencies for TMP whitewater.

scholarly journals Microbial Diversity Dynamics in a Methanogenic-Sulfidogenic UASB Reactor

2021 ◽  
Vol 18 (3) ◽  
pp. 1305
Author(s):  
E. Fernández-Palacios ◽  
Xudong Zhou ◽  
Mabel Mora ◽  
David Gabriel
Keyword(s):  
Paper Industry ◽  
Chemical Species ◽  
Methanogenic Archaea ◽  
Granular Sludge ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Rrna Gene ◽  
Sulfate Reducing ◽  
Long Run

In this study, the long-term performance and microbial dynamics of an Upflow Anaerobic Sludge Blanket (UASB) reactor targeting sulfate reduction in a SOx emissions treatment system were assessed using crude glycerol as organic carbon source and electron donor under constant S and C loading rates. The reactor was inoculated with granular sludge obtained from a pulp and paper industry and fed at a constant inlet sulfate concentration of 250 mg S-SO42−L−1 and a constant C/S ratio of 1.5 ± 0.3 g Cg−1 S for over 500 days. Apart from the regular analysis of chemical species, Illumina analyses of the 16S rRNA gene were used to study the dynamics of the bacterial community along with the whole operation. The reactor was sampled along the operation to monitor its diversity and the changes in targeted species to gain insight into the performance of the sulfidogenic UASB. Moreover, studies on the stratification of the sludge bed were performed by sampling at different reactor heights. Shifts in the UASB performance correlated well with the main shifts in microbial communities of interest. A progressive loss of the methanogenic capacity towards a fully sulfidogenic UASB was explained by a progressive wash-out of methanogenic Archaea, which were outcompeted by sulfate-reducing bacteria. Desulfovibrio was found as the main sulfate-reducing genus in the reactor along time. A progressive reduction in the sulfidogenic capacity of the UASB was found in the long run due to the accumulation of a slime-like substance in the UASB.

scholarly journals Simple estimation of granule size distribution and sludge bed porosity in a UASB reactor

2013 ◽  
Vol 10 (1) ◽  
pp. 73-79
Keyword(s):  
Size Distribution ◽  
Granular Sludge ◽  
Granule Size ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Reactor Performance ◽  
Efficient Operation ◽  
Mathematical Algorithm ◽  
Bed Porosity

Granular sludge is the key factor for an efficient operation of an upflow anaerobic sludge blanket (UASB) reactor. In order to monitor the granularity of anaerobic sludge, the determination of the granule size distribution is of vital importance. Another critical parameter for the UASB reactor performance is the sludge bed porosity. For this reason, several techniques have been proposed, however they are either tedious, imprecise or expensive and hardly applicable in full scale treatment plants. There was then the need for a simple and low cost technique. This technique involves the determination of the settling velocities of a sludge sample and of extrapolating the corresponding diameters using a mathematical algorithm. In the proposed algorithm, the granules density was calculated, the flow regime was examined and finally the granule size distribution was obtained. Some very important correlations were suggested by the experimental results. The granule density and diameter as well as the sludge bed porosity were strongly correlated with the VSS/TSS ratio.

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