scholarly journals Micropollutant removal from black water and grey water sludge in a UASB-GAC reactor

2017 ◽  
Vol 77 (4) ◽  
pp. 1137-1148 ◽  
Author(s):  
A. Butkovskyi ◽  
L. Sevenou ◽  
R. J. W. Meulepas ◽  
L. Hernandez Leal ◽  
G. Zeeman ◽  
...  

Abstract The effect of granular activated carbon (GAC) addition on the removal of diclofenac, ibuprofen, metoprolol, galaxolide and triclosan in a up-flow anaerobic sludge blanket (UASB) reactor was studied. Prior to the reactor studies, batch experiments indicated that addition of activated carbon to UASB sludge can decrease micropollutant concentrations in both liquid phase and sludge. In continuous experiments, two UASB reactors were operated for 260 days at an HRT of 20 days, using a mixture of source separated black water and sludge from aerobic grey water treatment as influent. GAC (5.7 g per liter of reactor volume) was added to one of the reactors on day 138. No significant difference in COD removal and biogas production between reactors with and without GAC addition was observed. In the presence of GAC, fewer micropollutants were washed out with the effluent and a lower accumulation of micropollutants in sludge and particulate organic matter occurred, which is an advantage in micropollutant emission reduction from wastewater. However, the removal of micropollutants by adding GAC to a UASB reactor would require more activated carbon compared to effluent post-treatment. Additional research is needed to estimate the effect of bioregeneration on the lifetime of activated carbon in a UASB-GAC reactor.

2011 ◽  
Vol 64 (3) ◽  
pp. 610-617 ◽  
Author(s):  
Tarek Elmitwalli ◽  
Ralf Otterpohl

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.


2012 ◽  
Vol 9 ◽  
pp. 57-62
Author(s):  
Fiza Sarwar ◽  
Wajeeha Malik ◽  
Muhammad Salman Ahmed ◽  
Harja Shahid

Abstract: This study was designed using actual effluent from the sugary mills in an Up-flow Anaerobic Sludge Blanket (UASB) Reactor to evaluate treatability performance. The reactor was started-up in step-wise loading rates beginning from 0.05kg carbon oxygen demand (COD)/m3-day to 3.50kg-COD/m3-day. The hydraulic retention time (HRT) was slowly decreased from 96 hrs to eight hrs. It was observed that the removal efficiency of COD of more than 73% can be easily achieved at an HRT of more than 16 hours corresponding to an average organic loading rate (OLR) of 3.0kg-COD/m3-day, at neutral pH and constant temperature of 29°C. The average VFAs (volatile fatty acids) and biogas production was observed as 560mg/L and 1.6L/g-CODrem-d, respectively. The average methane composition was estimated as 62%. The results of this study suggest that the treatment of sugar mills effluent with the anaerobic technology seems to be more reliable, effective and economical.DOI: http://dx.doi.org/10.3126/hn.v9i0.7075 Hydro Nepal Vol.9 July 2011 57-62


2001 ◽  
Vol 44 (4) ◽  
pp. 79-82 ◽  
Author(s):  
L. F. Lopes ◽  
P. R. Koetz ◽  
M. S. Santos

Parboiled rice industry is one of main food industries in the south of Brazil. The main parts of the processing are the humidification and gelatinization of the grain. This procedure increases the productivity and nutritive and cooking values of the product. Some of these industries in the region utilize upflow anaerobic sludge blanket (UASB) reactors as a biological treatment for carbon removal. For nitrogen removal, the proposed system aims to eliminate an extra denitrification reactor, making this step in the top of the UASB, an anoxic zone of the reactor. Nitrification was performed in aerated mixed reactor of 3,6 L. A fraction of the NR was recycled in the top of UASB reactor above the sludge blanket. Recycled ratio varied from 0; 1:0.5; 1:1.0; to 1:1.5. The maximum removal efficiency of NTK was 80%. The results confirm the viability of the proposed system for denitrification.


2021 ◽  
Vol 6 (4) ◽  
pp. 17-34
Author(s):  
Glenda A. Espinoza ◽  
◽  
Verónica Almaguer-Cantú ◽  
Refugio B. García-Reyes ◽  
Edna R. Meza ◽  
...  

Azo dyes are susceptible to be treated by reductive biotransformation process under anaerobic conditions. The process can be accelerated by the addition of quinones and humic substances acting as redox mediators (RM). In this study, the anthraquinone-2-sulfonate (AQS) was immobilized on granular activated carbon (GAC) to evaluate the reductive biotransformation of congo red (CR) in an up-flow anaerobic sludge blanket reactor (UASB). The syudy was divided in five stages, where the reactors with immobilized RM and without RM were operated under different salinity levels (1% and 3%) and hydraulic retention times (HRT = 5 and 10 h). The reactor with immobilized RM (GAC-AQS) achieved a decolorization efficiency of 96.1% and substrate consumption of 98.8% with a HRT = 15 h and 1% of salinity. Nonetheless, with a salinity of 3% and the same HRT, the efficiency was similar (95.6%). The reactor provided with unmodified GAC achieved values below those observed in the reactor GAC-AQS, with decolorization efficiencies of 90.8% and 75.8%, and substrate consumption of 97.1% and 88.4%, for the stages IV and V, respectively. The microbial consortium sued was able to promote the biotransformation of azo dye and no inhibitory effects were identified.


1995 ◽  
Vol 31 (1) ◽  
pp. 249-259 ◽  
Author(s):  
Nina Christiansen ◽  
Hanne V. Hendriksen ◽  
Kimmo T. Järvinen ◽  
Birgitte K. Ahring

Data on anaerobic degradation of chloroaromatic compounds in Upflow Anaerobic Sludge Blanket Reactors (UASB-reactor) are presented and compared. Special attention is given to the metabolic pathways for degradation of chlorinated phenols by granular sludge. Results indicate that PCP can be degraded in UASB-reactors via stepwise dechlorination to phenol. Phenol will subsequently be converted to benzoate before ring cleavage. Dechlorination proceeds via different pathways dependent upon the inocula used. Results are further presented on the design of special metabolic pathways in granules which do not possess this activity using the dechlorinating organism, Desulfomonile tiedjei. Additionally, it is shown that it is possible to immobilize Dechlorosporium hafniense, a newly isolated dechlorinating anaerobe, into granular sludge, thereby introducing an ability not previously present in the granules.


2019 ◽  
Vol 80 (8) ◽  
pp. 1505-1511 ◽  
Author(s):  
Nathalie Dyane Miranda Slompo ◽  
Larissa Quartaroli ◽  
Grietje Zeeman ◽  
Gustavo Henrique Ribeiro da Silva ◽  
Luiz Antonio Daniel

Abstract Decentralized sanitary wastewater treatment has become a viable and sustainable alternative, especially for developing countries and small communities. Besides, effluents may present variations in chemical oxygen demand (COD), biochemical oxygen demand (BOD) and total nitrogen values. This study describes the feasibility of using a pilot upflow anaerobic sludge blanket (UASB) reactor to treat wastewater with different organic loads (COD), using black water (BW) and sanitary wastewater, in addition to its potential for preserving nutrients for later recovery and/or reuse. The UASB reactor was operated continuously for 95 weeks, with a hydraulic retention time of 3 days. In Phase 1, the reactor treated simulated BW and achieved 77% CODtotal removal. In Phase 2, treating only sanitary wastewater, the CODtotal removal efficiency was 60%. Phase 3 treated simulated BW again, and CODtotal removal efficiency was somewhat higher than in Phase 1, reaching 81%. In Phase 3, the removal of pathogens was also evaluated: the efficiency was 1.96 log for Escherichia coli and 2.13 log for total coliforms. The UASB reactor was able to withstand large variations in the organic loading rate (0.09–1.49 kg COD m−3 d−1), in continuous operation mode, maintaining a stable organic matter removal.


2021 ◽  
Vol 47 (1) ◽  
pp. 174-180
Author(s):  
Henrique Sousa do Nascimento ◽  
Geísa Vieira Vasconcelos Magalhães ◽  
José Demontier Vieira de Souza-Filho ◽  
Ronaldo Stefanutti ◽  
Ari Clecius Alves de Lima ◽  
...  

This study evaluated the use of two anaerobic bioreactors in the production of biogas from malt bagasse waste. Bioreactor B1 was loaded with a mixture of 600mL of anaerobic sludge, 300g of organic waste, taken from an upflow anaerobic sludge blanket (UASB) reactor, and 300g of malt bagasse residue. Bioreactor B2 was loaded with a mixture of 600g of organic waste and 600mL of anaerobic sludge taken from an UASB reactor. The anaerobic digestion processes lasted for 10 weeks and the produced methane fraction was measured in 5 occasions. Bioreactor B1 presented low methane production (7.2%) but Bioreactor B2 showed a much more signif- icant percentage, reaching up to 48.3%. The experiments were capable of reproducing largescale operational conditions, enabling increased results in biogas capturing and processing, strengthening sustainability and energy efficiency. The experiment also showed the importance of studying different types of organic waste, seeking optimization of anaerobic digestion pro- cesses.


2006 ◽  
Vol 53 (9) ◽  
pp. 45-54 ◽  
Author(s):  
Tarek Elmitwalli ◽  
Yucheng Feng ◽  
Joachim Behrendt ◽  
Ralf Otterpohl

The potential of anaerobic digestion in ecological and decentralised sanitation has been investigated in this research. Different anaerobic digestion systems were proposed for the treatment of sewage, grey water, black water and faeces. Moreover, mathematical models based on anaerobic digestion model no.1 (ADM1) were developed for determination of a suitable design for each system. For stable performance of an upflow anaerobic sludge blanket (UASB) reactor treating sewage, the model results indicated that optimisation of wastewater conversion to biogas (not COD removal) should be selected for determination of the hydraulic retention time (HRT) of the reactor. For the treatment of sewage or black water in a UASB septic-tank, the model results showed that the sludge removal period was the main parameter for determination of the HRT. At such HRT, both COD removal and wastewater conversion are also optimised. The model results demonstrated that for treatment of faeces in an accumulation (AC) system at temperature ≥25 °C, the filling period of the system should be higher than 60 days. For maximisation of the net biogas production (i.e. reduction of biogas losses as dissolved in the effluent), the separation between grey water, urine and faeces and reduction of water consumption for faeces flushing are required. Furthermore, the faeces and kitchen organic wastes and grey water are digested in, respectively, an AC system and UASB reactor, while the urine is stored.


2014 ◽  
Vol 953-954 ◽  
pp. 1105-1108 ◽  
Author(s):  
Seni Karnchanawong ◽  
Kraiwet Kabtum

The objective of this study was to investigate the toxicity of Na+and K+ions on performance of upflow anaerobic sludge blanket (UASB) system. Three laboratory-scale UASB reactors, 15.8 - l working volume, were employed with 1 reactor operated as control. They were loaded at organic loading rate (OLR) of 5 kg COD/(m3-d), treating synthetic wastewater with COD concentration ~ 5000 mg/l. Na+and K+ions were added in the range of 1010 - 7180 and 41 - 7320 mg/l, respectively. No toxicity was observed at influent Na+and K+concentrations up to 3340 and 2750 mg/l, respectively. Slight inhibitions on COD removal were founded at Na+and K+concentrations of 4610 and 3920 mg/l, respectively, but moderate effect on biogas production had occurred. When Na+and K+concentrations were increased to 7180 and 7320 mg/l, respectively, strong inhibitions were observed with COD removal dropped to 45.5 and 48.8 %, respectively. Ratios of biogas productions, as compared to the control reactor, were dropped to 0.31 and 0.32, respectively. Increasing cation concentrations had more detrimental effect on biogas production than COD removal.


2009 ◽  
Vol 59 (11) ◽  
pp. 2265-2272 ◽  
Author(s):  
S. Satyanarayan ◽  
A. Karambe ◽  
A. P. Vanerkar

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.


Sign in / Sign up

Export Citation Format

Share Document