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.

Degradation of chlorinated aromatic compounds in UASB reactors

1995 ◽  
Vol 31 (1) ◽  
pp. 249-259 ◽  
Author(s):  
Nina Christiansen ◽  
Hanne V. Hendriksen ◽  
Kimmo T. Järvinen ◽  
Birgitte K. Ahring
Keyword(s):  
Metabolic Pathways ◽  
Granular Sludge ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Ring Cleavage ◽  
Anaerobic Sludge ◽  
Chlorinated Phenols ◽  
Desulfomonile Tiedjei ◽  
Anaerobic Sludge Blanket ◽  
Uasb Reactors

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.

Toxicity of Sodium and Potassium Ions on Performance of UASB System

2014 ◽  
Vol 953-954 ◽  
pp. 1105-1108 ◽  
Author(s):  
Seni Karnchanawong ◽  
Kraiwet Kabtum
Keyword(s):  
Biogas Production ◽  
Cod Removal ◽  
Upflow Anaerobic Sludge Blanket ◽  
Synthetic Wastewater ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
Working Volume ◽  
Anaerobic Sludge Blanket ◽  
Uasb Reactors ◽  
Sodium And Potassium

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.

Modeling simultaneous removal of primary substrates and chlorinated phenols in upflow anaerobic sludge blanket reactors

2001 ◽  
Vol 28 (6) ◽  
pp. 910-921 ◽  
Author(s):  
K J Kennedy ◽  
Z Ning ◽  
L Fernandes
Keyword(s):  
Dynamic Model ◽  
Model Development ◽  
Oxygen Demand ◽  
Upflow Anaerobic Sludge Blanket ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
Chlorinated Phenols ◽  
Degradation Rates ◽  
Anaerobic Sludge Blanket ◽  
Uasb Reactors

A dynamic model describing the simultaneous degradation of easily degradable substrates (sucrose and acetic acid (HAc)) and 2,4-dichlorophenol (2,4-DCP) in upflow anaerobic sludge blanket (UASB) reactors was developed. The two critical factors considered in the model development were sorption and substrate interaction during degradation. Data obtained from experiments on the multiple substrate degradation in continuous UASB reactors were used to validate and verify the dynamic model. The model predicts the system responses for 2,4-DCP, 4-monochlorophenol (4-MCP), HAc, propionic acid (HPr), and chemical oxygen demand (COD) concentration in the effluent. The modeling results indicated that the degradation rates for 2,4-DCP and for cosubstrates, HAc and HPr, changed inversely as a function of the specific organic loading rate for UASB reactors.Key words: dynamic, modeling, UASB, 2,4-dichlorophenol, sorption, degradation, co-metablism.

scholarly journals A Comparative Study of Biogas Production from Cattle Slaughterhouse Wastewater Using Conventional and Modified Upflow Anaerobic Sludge Blanket (UASB) Reactors

2019 ◽  
Vol 17 (1) ◽  
pp. 283 ◽  
Author(s):  
Mohammed Ali Musa ◽  
Syazwani Idrus ◽  
Mohd Razif Harun ◽  
Tuan Farhana Tuan Mohd Marzuki ◽  
Abdul Malek Abdul Wahab
Keyword(s):  
Loading Condition ◽  
Biogas Production ◽  
Bacterial Species ◽  
High Strength ◽  
Upflow Anaerobic Sludge Blanket ◽  
Synthetic Wastewater ◽  
Anaerobic Sludge ◽  
Slaughterhouse Wastewater ◽  
Anaerobic Sludge Blanket ◽  
Uasb Reactors

Cattle slaughterhouses generate wastewater that is rich in organic contaminant and nutrients, which is considered as high strength wastewater with a high potential for energy recovery. Work was undertaken to evaluate the efficiency of the 12 L laboratory scale conventional and a modified upflow anaerobic sludge blanket (UASB) reactors (conventional, R1 and modified, R2), for treatment of cattle slaughterhouse wastewater (CSWW) under mesophilic condition (35 ± 1 °C). Both reactors were acclimated with synthetic wastewater for 30 days, then continuous study with real CSWW proceeds. The reactors were subjected to the same loading condition of OLR, starting from 1.75, 3, 5 10, 14, and 16 g L−1d−1, corresponding to 3.5, 6, 10, 20, 28, and 32 g COD/L at constant hydraulic retention time (HRT) of 24 h. The performance of the R1 reactor drastically dropped at OLR 10 g L−1d−1, and this significantly affected the subsequent stages. The steady-state performance of the R2 reactor under the same loading condition as the R1 reactor revealed a high COD removal efficiency of 94% and biogas and methane productions were 27 L/d and 89%. The SMP was 0.21 LCH4/gCOD added, whereas the NH3-N alkalinity ratio stood at 651 mg/L and 0.2. SEM showed that the R2 reactor was dominated by Methanosarcina bacterial species, while the R1 reactor revealed a disturb sludge with insufficient microbial biomass.

Improved nitrogen removal in upflow anaerobic sludge blanket (UASB) reactors by incorporation of Anammox bacteria into the granular sludge

2004 ◽  
Vol 49 (11-12) ◽  
pp. 69-76 ◽  
Author(s):  
J.E. Schmidt ◽  
D.J. Batstone ◽  
I. Angelidaki
Keyword(s):  
In Situ Hybridisation ◽  
Granular Sludge ◽  
Ammonia Removal ◽  
Appropriate Technology ◽  
Upflow Anaerobic Sludge Blanket ◽  
Anaerobic Sludge ◽  
The Third ◽  
Anammox Activity ◽  
Anaerobic Sludge Blanket ◽  
Uasb Reactors

Upflow anaerobic sludge blanket reactors may offer a number of advantages over conventional mixed-tank, SBR, and biofilm reactors, including high space-loading, low footprint, and resistance to shocks and toxins. In this study, we assessed the use of upflow anaerobic sludge blanket (UASB) reactor technology as applied to anaerobic ammonia removal, or Anammox. Four 200 ml UASB reactors were inoculated with 50% (by volume) anaerobic granular sludge and 50% flocular sludge from different sources (all with the potential for containing Anammox organisms). Tools used to assess the reactors included basic analyses, fluorescent in-situ hybridisation, and mathematical modelling, with statistical non-linear parameter estimation. Two of the reactors showed statistically identical Anammox activity (i.e., identical kinetic parameters), with good ammonia and nitrite removal (0.14 kgNHx m-3 reactor day-1, with 99% ammonia removal). The third reactor also demonstrated significant Anammox activity, but with poor identifiability of parameters. The fourth reactor had no statistical Anammox activity. Modelling indicated that poor identifiability and performance in the third and fourth reactors were related to an excess of reduced carbon, probably originating in the inoculum. Accumulation of Anammox organisms was confirmed both by a volume loading much lower than the growth rate, and response to a probe specific for organisms previously reported to mediate Anammox processes. Overall, the UASB reactors were effective as Anammox systems, and identifiability of the systems was good, and repeatable (even compared to a previous study in a rotating biological contactor). This indicates that operation, design, and analysis of Anammox UASB reactors specifically, and Anammox systems in general, are reliable and portable, and that UASB systems are an appropriate technology for this process.

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 Constraints, performance and perspectives of anaerobic sewage treatment: lessons from full-scale sewage treatment plants in Brazil

2019 ◽  
Vol 80 (3) ◽  
pp. 418-425 ◽  
Author(s):  
T. Bressani-Ribeiro ◽  
L. A. Chamhum-Silva ◽  
C. A. L. Chernicharo
Keyword(s):  
Sewage Treatment ◽  
Full Scale ◽  
Upflow Anaerobic Sludge Blanket ◽  
Operational Performance ◽  
Anaerobic Sludge ◽  
Anaerobic Reactors ◽  
Anaerobic Sludge Blanket ◽  
Operational Constraints ◽  
Uasb Reactors ◽  
Design Construction

Abstract There are hundreds of full-scale upflow anaerobic sludge blanket (UASB) reactors in operation in various parts of the tropical world, notably in India and Latin America, Brazil being the holder of the largest park of anaerobic reactors for sewage treatment in the world. Despite the recognized advantages of UASB reactors, there are problems that have prevented their maximum operational performance. Neglecting the existence and delaying the solution of these challenges can jeopardize the important advances made to date, impacting the future of anaerobic technology in Brazil and in other countries. This work aims to evaluate the operational performance of five full-scale UASB reactors in Brazil, taking into account a monitoring period ranging between two and six years. The main observed design, construction, and operational constraints are discussed. Some outlooks for important upcoming developments are also provided, considering that most of the observed drawbacks can be tackled without significant increases on reactor costs.

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