Sequential anaerobic/aerobic biotreatment of bark leachate

2003 ◽  
Vol 48 (6) ◽  
pp. 203-209 ◽  
Author(s):  
J.C. Frigon ◽  
R. Cimpoia ◽  
S.R. Guiot
Keyword(s):  
Oxygen Demand ◽  
Anaerobic Treatment ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Phenol Removal ◽  
Aerobic Treatment ◽  
Hydraulic Residence Time ◽  
Operational Conditions ◽  
Fixed Film ◽  
Air Diffusion

Bark leachate is generated from sawmill operations such as log storage sites and contains polymeric tannins, carbohydrates, organic acids, phenolic and resin compounds. The present study was aimed at assessing the performance of a sequential anaerobic and aerobic treatment, for both chemical oxygen demand (COD) and phenol removal, under various combinations of operational conditions, in the continuous mode. After anaerobic treatment in a five litres upflow anaerobic sludge bed (UASB) reactor, the leachate was directed into two parallel aerobic reactors, either an activated sludge unit or a fixed film submerged filter (packed with polyethylene Flexirings), both of a volume of one litre and oxygenated by air diffusion. For a leachate of 22 gCOD/l, an overall COD removal of 96Ð98% was achieved at an hydraulic residence time (HRT) of 4 days for the anaerobic reactor and one day for either aerobic systems. The phenol concentration generally increased after anaerobic treatment but was below the detection limit (50 ppb) after aerobic polishing. Radiorespirometric microcosms with 14C-labelled phenol confirmed that phenol was mineralized in the aerobic reactors. The performances of both aerobic systems were similar for COD and phenol removal. Thus, a sequential anaerobic/aerobic treatment was able to effectively address the contamination of a bark leachate discharge, including phenols.

Anaerobic treatment of crude glycerol from biodiesel production

2015 ◽  
Vol 72 (8) ◽  
pp. 1383-1389 ◽  
Author(s):  
M. M. Nakazawa ◽  
W. R. S. Silva Júnior ◽  
M. T. Kato ◽  
S. Gavazza ◽  
L. Florencio
Keyword(s):  
Crude Glycerol ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Biogas Production ◽  
Oxygen Demand ◽  
Experimental Period ◽  
Anaerobic Treatment ◽  
Biodiesel Production ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Reactor Performance

In this study, we evaluated the use of an up-flow anaerobic sludge blanket (UASB) reactor to treat crude glycerol obtained from cottonseed biodiesel production. The laboratory-scale UASB reactor (7.0 L) was operated at ambient temperature of 26.5°C with chemical oxygen demand (COD) concentrations between 0.5 and 8.0 g/L. The volatile fatty acid contents, pH, inorganic salt contents and biogas production were monitored during a 280-day experimental period. Molecular biology techniques were used to assess the microbial diversity in the bioreactor. The reactor achieved COD removal efficiencies of up to 92% except during one phase when the efficiency decreased to 81%. Biogas production remained stable throughout the experimental period, when the fraction converted to methane reached values as high as 68%. The profile of the denaturing gradient gel electrophoresis (DGGE) bands suggested slight changes in the microbial community during reactor operation. The overall results indicated that the crude glycerol from biodiesel production can serve as a suitable substrate for anaerobic degradation with a stable reactor performance and biogas production as long as the applied organic loads are up to 8.06 kg COD/m3·d.

Effective carbon and nutrient treatment solutions for mixed domestic-industrial wastewater in India

2015 ◽  
Vol 72 (4) ◽  
pp. 651-657 ◽  
Author(s):  
S. Saha ◽  
N. Badhe ◽  
D. Seuntjens ◽  
S. E. Vlaeminck ◽  
R. Biswas ◽  
...  
Keyword(s):  
Nutrient Removal ◽  
Urban Areas ◽  
Treatment Options ◽  
Sewage Treatment ◽  
Oxygen Demand ◽  
Anaerobic Treatment ◽  
Fecal Coliforms ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Anaerobic Sludge Blanket

The present study evaluates effectiveness of up-flow anaerobic sludge blanket (UASB) reactor followed by two post-anaerobic treatment options, namely free-surface, up-flow constructed wetland (FUP-CW) and oxygen-limited anaerobic nitrification/denitrification (OLAND) processes in treating sewage from the peri-urban areas in India receiving illegal industrial infiltrations. The UASB studies yielded robust results towards fluctuating strength of sewage and consistently removed 87–98% chemical oxygen demand (COD) at a hydraulic retention time of 1.5–2 d. The FUP-CW removed 68.5 ± 13% COD, 68 ± 3% NH4+-N, 38 ± 5% PO43−-P, 97.6 ± 5% suspended particles and 97 ± 13% fecal coliforms. Nutrient removal was found to be limiting in FUP-CW, especially in winter. Nitrogen removal in the OLAND process were 100 times higher than the FUP-CW process. Results show that UASB followed by FUP-CW can be an excellent, decentralized sewage treatment option, except during winter when nutrient removal is limited in FUP-CW. Hence, the study proposes bio-augmentation of FUP-CW with OLAND biomass for overall improvement in the performance of UASB followed by FUP-CW process.

Diversity and dynamics of ammonia-oxidizing bacterial communities in a sponge-based trickling filter treating effluent from a UASB reactor

2013 ◽  
Vol 68 (3) ◽  
pp. 650-657 ◽  
Author(s):  
E. F. A. Mac Conell ◽  
P. G. S. Almeida ◽  
A. M. Zerbini ◽  
E. M. F. Brandt ◽  
J. C. Araújo ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Oxygen Demand ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
Trickling Filter ◽  
Strong Concentration ◽  
Operational Conditions ◽  
N Removal

Changes in ammonia-oxidizing bacterial (AOB) population dynamics were examined in a new sponge-based trickling filter (TF) post-upflow anaerobic sludge blanket (UASB) reactor by denaturating gradient gel electrophoresis (DGGE), and these changes were linked to relevant components influencing nitrification (chemical oxygen demand (COD), nitrogen (N)). The sponge-based packing media caused strong concentration gradients along the TF, providing an ecological selection of AOB within the system. The organic loading rate (OLR) affected the population dynamics, and under higher OLR or low ammonium-nitrogen (NH4+-N) concentrations some AOB bands disappeared, but maintaining the overall community function for NH4+-N removal. The dominant bands present in the upper portions of the TF were closely related to Nitrosomonas europaea and distantly affiliated to Nitrosomonas eutropha, and thus were adapted to higher NH4+-N and organic matter concentrations. In the lower portions of the TF, the dominant bands were related to Nitrosomonas oligotropha, commonly found in environments with low levels of NH4+-N. From a technology point of view, changes in AOB structure at OLR around 0.40–0.60 kgCOD m−3 d−1 did not affect TF performance for NH4+-N removal, but AOB diversity may have been correlated with the noticeable stability of the sponge-based TF for NH4+-N removal at low OLR. This study is relevant because molecular biology was used to observe important features of a bioreactor, considering realistic operational conditions applied to UASB/sponge-based TF systems.

scholarly journals Performance of UASB reactors in two stages under different HRT and OLR treating residual waters of swine farming

2013 ◽  
Vol 33 (2) ◽  
pp. 367-378 ◽  
Author(s):  
Estevão Urbinati ◽  
Rose M. Duda ◽  
Roberto A. de Oliveira
Keyword(s):  
Oxygen Demand ◽  
Pilot Scale ◽  
Anaerobic Treatment ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
In Series ◽  
Two Stages ◽  
Uasb Reactors

In this study it was evaluated the effects of hydraulic retention time (HRT) and Organic Loading Rate (OLR) on the performance of UASB (Upflow Anaerobic Sludge Blanket) reactors in two stages treating residual waters of swine farming. The system consisted of two UASB reactors in pilot scale, installed in series, with volumes of 908 and 188 L, for the first and second stages (R1 and R2), respectively. The HRT applied in the system of anaerobic treatment in two stages (R1 + R2) was of 19.3, 29.0 and 57.9 h. The OLR applied in the R1 ranged from 5.5 to 40.1 kg CODtotal (m³ d)-1. The average removal efficiencies of chemical oxygen demand (COD) and total suspended solids (TSS) ranged, respectively, from 66.3 to 88.2% and 62.5 to 89.3% in the R1, and from 85.5 to 95.5% and 76.4 to 96.1% in the system (R1 + R2). The volumetric production of methane in the system (R1 + R2) ranged from 0.295 to 0.721 m³CH4 (m³ reactor d)-1. It was found that the OLR applied were not limiting to obtain high efficiencies of CODtotal and TSS removal and methane production. The inclusion of the UASB reactor in the second stage contributed to increase the efficiencies of CODtotal and TSS removal, especially, when the treatment system was submitted to the lowest HRT and the highest OLR.

Grey water treatment in upflow anaerobic sludge blanket (UASB) reactor at different temperatures

2011 ◽  
Vol 64 (3) ◽  
pp. 610-617 ◽  
Author(s):  
Tarek Elmitwalli ◽  
Ralf Otterpohl
Keyword(s):  
Oxygen Demand ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Septic Tank ◽  
Anaerobic Sludge ◽  
Grey Water ◽  
Methanogenic Activity ◽  
Operational Conditions ◽  
Anaerobic Sludge Blanket ◽  
Uasb Reactors

The treatment of grey water in two upflow anaerobic sludge blanket (UASB) reactors, operated at different hydraulic retention times (HRTs) and temperatures, was investigated. The first reactor (UASB-A) was operated at ambient temperature (14–25 °C) and HRT of 20, 12 and 8 h, while the second reactor (UASB-30) was operated at controlled temperature of 30 °C and HRT of 16, 10 and 6 h. The two reactors were fed with grey water from ‘Flintenbreite’ settlement in Luebeck, Germany. When the grey water was treated in the UASB reactor at 30 °C, total chemical oxygen demand (CODt) removal of 52–64% was achieved at HRT between 6 and 16 h, while at lower temperature lower removal (31–41%) was obtained at HRT between 8 and 20 h. Total nitrogen and phosphorous removal in the UASB reactors were limited (22–36 and 10–24%, respectively) at all operational conditions. The results showed that at increasing temperature or decreasing HRT of the reactors, maximum specific methanogenic activity of the sludge in the reactors improved. As the UASB reactor showed a significantly higher COD removal (31–64%) than the septic tank (11–14%) even at low temperature, it is recommended to use UASB reactor instead of septic tank (the most common system) for grey water pre-treatment. Based on the achieved results and due to high peak flow factor, a HRT between 8 and 12 h can be considered the suitable HRT for the UASB reactor treating grey water at temperature 20–30 °C, while a HRT of 12–24 h can be applied at temperature lower than 20 °C.

Evaluation of aerobic and anaerobic treatment of Kraft pulp mill effluent for organochlorines removal

2006 ◽  
Vol 1 (3) ◽  
Author(s):  
A. P. Buzzini ◽  
M. A. Nolasco ◽  
A. M. Springer ◽  
E. C. Pires
Keyword(s):  
Activated Sludge ◽  
Black Liquor ◽  
Oxygen Demand ◽  
Pulp Mill ◽  
Anaerobic Treatment ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Individual Values ◽  
Activated Sludge Reactor

The purposes of the experiments described in this paper were to evaluate the performance of an upflow anaerobic sludge blanket (UASB) activated sludge reactor, both bench scale reactors, in the treatment of wastewaters containing organochlorines compounds, which simulate a kraft plant wastewater. Both reactors received a wastewater prepared with diluted black liquor and a mixture of organochlorines: 2 Chlorophenol (2 CP); 2,4 Dichlorophenol (2,4 DCP); 2,6 Dichlorophenol (2,6 DCP); 2,4,6 Trichlorophenol (2,4,6 TCP); and Tetrachlorocatechol (TeCC). The activated sludge reactor also received 4, 5, 6 Trichloroguaiacol (4, 5, 6 TCG). The chemical oxygen demand (COD) and organochlorine concentrations in the effluent indicated that the two systems displayed a similar performance in terms of COD removal, with average efficiencies of 79% for the UASB reactor and of 77% for the activated sludge reactor. The average individual values for organochlorine removal efficiency, the first figure representing the UASB reactor removal, were: 99.9% and 91% for the 2 CP; 97% and 80% for the 2,4 DCP; 94% and 80% for the 2,6 DCP; 99% and 75% for the 2,4,6 TCP; and 93% and 90% for the TeCC. Both systems showed to be capable of treating pulp plant wastewaters containing chlorophenols, with a certain advantage for the anaerobic system from the standpoint of removal efficiencies.

scholarly journals Anaerobic treatment of coconut husk liquor for biogas production

2009 ◽  
Vol 59 (9) ◽  
pp. 1841-1846 ◽  
Author(s):  
R. C. Leitão ◽  
A. M. Araújo ◽  
M. A. Freitas-Neto ◽  
M. F. Rosa ◽  
S. T. Santaella
Keyword(s):  
Biogas Production ◽  
Oxygen Demand ◽  
Anaerobic Treatment ◽  
Raw Material ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Toxicity Tests ◽  
Anaerobic Sludge ◽  
Methanogenic Activity ◽  
Coconut Husk

The market for coconut water causes environmental problems as it is one of the major agro-industrial solid wastes in some developing countries. With the aim of reusing the coconut husk, Embrapa developed a system for processing this raw material. During the dewatering stage Coconut Husk Liquor (CHL) is generated with chemical oxygen demand (COD) varying from 60 to 70 g/L due to high concentrations of sugars and tannins. The present study evaluated the feasibility of anaerobic treatment of CHL through Anaerobic Toxicity Assay and the operation of a lab-scale Upflow Anaerobic Sludge Blanket (UASB) reactor. Results showed that CHL can be treated through a UASB reactor operating with an OLR that reaches up to 10 kg/m3·d and that is maintained stable during the whole operation. With this operational condition, the removal efficiency was higher than 80% for COD and approximately 78% for total tannins, and biogas production was 20 m3 of biogas or 130 KWh per m3 of CHL. Seventy-five percent of the biogas composition was methane and toxicity tests demonstrated that CHL was not toxic to the methanogenic consortia. Conversely, increasing the concentration of CHL leads to increased methanogenic activity.

scholarly journals Biological treatment of whey in an UASFF bioreactor followed a three-stage RBC

2010 ◽  
Vol 16 (2) ◽  
pp. 175-182 ◽  
Author(s):  
Atiye Ebrahimi ◽  
Ghasem Najafpour ◽  
Maedeh Mohammadi ◽  
Babak Hashemiyeh
Keyword(s):  
Biological Treatment ◽  
High Strength ◽  
Anaerobic Treatment ◽  
Cod Removal ◽  
Anaerobic Sludge ◽  
Aerobic Treatment ◽  
Rotating Biological Contactor ◽  
Anaerobic Process ◽  
Fixed Film ◽  
Removal Efficiencies

Biological treatment of a high strength chesses whey wastewater was investigated in a series of aerobic-anaerobic experiments. Aerobic treatment of the wastewater was conducted in a three-stage rotating biological contactor (NRBC), while the anaerobic process was performed in an up-flow anaerobic sludge fixed film (UASFF) bioreactor. Various concentrations of wastewater with influent COD of 40,000 to 70,000 mg/L were introduced in to NRBC system. Treatability of the samples at various HRTs of 8, 12 and 16 h was evaluated in the NRBC reactor. The effluent streams of the NRBC system were introduced into UASFF bioreactor. Anaerobic treatment of the pretreated samples was investigated in an UASFF with the same HRTs of 8, 12 and 16 h. The obtained results revealed that more than 53, 69 and 78% of the influent COD (50,000 mg/L) were removed in NRBC reactor at HRTs of 8, 12 and 16 h, respectively. Maximum COD removal efficiencies of 96, 96.8, 97.4 and 96.4% were achieved in the combined systems at total HRT of 32 h for influent COD of 40,000, 50,000, 60,000 and 70,000 mg/L, respectively.

scholarly journals The effect of operational conditions on the hydrodynamic characteristics of the sludge bed in UASB reactors

2011 ◽  
Vol 64 (9) ◽  
pp. 1935-1941 ◽  
Author(s):  
R. C. Leitão ◽  
S. T. Santaellla ◽  
A. C. van Haandel ◽  
G. Zeeman ◽  
G. Lettinga
Keyword(s):  
Retention Time ◽  
Hydraulic Retention Time ◽  
Oxygen Demand ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Hydrodynamic Characteristics ◽  
Anaerobic Sludge ◽  
Fluidised Bed ◽  
Operational Conditions ◽  
Uasb Reactors

This work aims to evaluate the hydrodynamic properties of the sludge bed of Upflow Anaerobic Sludge Blanket (UASB) reactors based on its settleability and expansion characteristics. The methodologies used for the evaluation of the settleability of aerobic activated sludge, and for the expansibility of a sludge bed of Expanded Granular Sludge Bed reactors and Fluidised Bed Reactors were adapted and applied to the particular characteristics of the sludge of UASB reactors. An easy-to-build experimental set-up was developed to assess the parameters necessary for the equations of settleability and of expansibility. The results obtained from the sludges of seven differently operated reactors show that, for the treatment of low strength wastewater, settleability increased and expansibility decreased at decreased hydraulic retention time, from 6 to 1 h, and/or increased influent concentrations, from 136 to approximately 800 mg chemical oxygen demand/L. The results also show that it is useless to design an UASB reactor with a longer hydraulic retention time to cope with hydraulic shock loads, as a more expansible sludge will develop at such condition.

APLIKASI PROSES DIGESTASI ANAEROBIK LUMPUR BIOLOGI INSTALASI PENGOLAHAN AIR LIMBAH INDUSTRI KERTAS

2014 ◽  
Vol 4 (02) ◽  
Author(s):  
Rina S. Soetopo ◽  
Sri Purwati ◽  
Henggar Hardiani ◽  
Mukharomah Nur Aini ◽  
Krisna Adhitya Wardhana
Keyword(s):  
Oxygen Demand ◽  
Total Solid ◽  
Pilot Scale ◽  
Organic Content ◽  
Solid Content ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Organic Loading ◽  
Total Solid Content ◽  
Average Value

A continuous pilot scale study has been conducted to investigate the effectiveness of anaerobic digestion of biological sludge. The sludge has a total solid content of 0.53% - 1.1%, pH of 7.20 to 7.32. Its organic content is about 97 %, The research were conducted in two stages, which are acidification (performed in 3 m3 the Continously Stirred Tank Reactor/CSTR at pH of 5.5 to 6.0) and methanation (performed in 5 m3 the Up Flow Anaerobic Sludge Blanket/UASB reactor at pH 6.5 to 7.0). The retention time (RT) was gradually shortened from 6 days to 1 day for acidification and from 8 days to 2 days for methanation. The results showed that operating the CSTR at the RT of 1 day and the organic loading of 8.23 g Volatile Solid (VS)/m3.day could produce Volatile Fatty Acid (VFA) at an average value of 17.3 g/kg VS.day. Operating the UASB reactor at the RT of 2 days and the organic loading (Chemical Oxygen Demand/COD) of 2.4 kg COD/m3.day could produce biogas at an average value of 66.3 L/day, with an average methane content of 69.9%, methane rate of 0.17 L CH4/g COD reduction or 19.06 L CH4/kg VS. Furthermore, methanation could reduce COD at an average value of 51.2 %, resulting in the effluent average value of COD filtrate and COD total of 210.1 mg/L and 375.2 mg /L, respectively.Keywords: acidification, methanation, CSTR, UASB, biogas ABSTRAKPercobaan digestasi anaerobik lumpur IPAL biologi industri kertas secara kontinyu skala pilot telah dilakukan di industri kertas dengan tujuan mengkaji efektivitas proses digestasi anaerobik dalam mengolah lumpur tersebut. Lumpur yang digunakan memiliki total solids sekitar 0,53% – 1,1%, pH netral (7,20 – 7,32) dengan komponen utama senyawa organik sekitar 97%. Percobaan dilakukan dalam dua tahap yaitu asidifikasi dalam reaktor CSTR berkapasitas 3 m3 pada pH 5,5 – 6,0 dan metanasi dalam reaktor UASB berkapasitas 5 m3 pada pH 6,5 – 7,0. Percobaan dilakukan dengan waktu retensi yang dipersingkat secara bertahap dari 6 hari ke 1 hari untuk proses asidifikasi dan dari 8 hari ke 2 hari untuk proses metanasi. Hasil percobaan menunjukkan bahwa pengoperasian reaktor CSTR dengan waktu retensi 1 hari dan beban organik 8,3 g VS/m3.hari dapat menghasilkan VFA rata-rata 17,3 g/kg VS.hari dengan kisaran 8,36 – 30,59 g/kg VS.hari, sedangkan pengoperasian reaktor UASB pada waktu retensi 2 hari dan beban organik 2,4 kg COD/m3.hari dapat menghasilkan biogas rata-rata 66,3 L/hari dengan kadar metana rata-rata 69,9% atau 0,17 L CH4/g COD reduksi atau 19,06 L CH4/kg VS. Selain itu proses metanasi dapat menurunkan COD terlarut rata-rata 51,2%, dengan konsentrasi efluen COD terlarut  rata-rata 210,1 mg/L dan COD total rata-rata 375,2 mg/L.Kata kunci: asidifikasi, metanasi, CSTR, UASB, biogas

Sign in / Sign up

Export Citation Format

Share Document