The operation of two EGSB reactors under the application of different loads of oxytetracycline and florfenicol

2012 ◽  
Vol 66 (12) ◽  
pp. 2578-2585 ◽  
Author(s):  
Yudy Andrea Londoño ◽  
Diana Catalina Rodríguez ◽  
Gustavo Peñuela
Keyword(s):  
Bacterial Population ◽  
Oxygen Demand ◽  
Dairy Farm ◽  
Granular Sludge ◽  
Inhibitory Effect ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Pellet Size ◽  
Anaerobic Sludge Blanket

This study evaluated the effect of the antibiotics oxytetracycline (OTC) and florfenicol (FLO) on the operation of two EGSB (expanded granular sludge bed) reactors. The experiment was conducted for 210 d in reactor R1 and 245 d in reactor R2. The reactors were inoculated with granular sludge from a upflow anaerobic sludge blanket (UASB) reactor on a local dairy farm. The sludge had an average pellet size of 2.35 mm, good sedimentability and a high percentage of organic material. The antibiotic tolerance and the inhibitory action on the bacterial population were different for each antibiotic studied. The results showed a more severe inhibitory effect on microorganisms that were in contact with increases in loads of FLO than those that were in contact with increasing loads of OTC, a condition reflected in the chemical oxygen demand (COD) removal efficiency.

Acid Endurance and Sorption of Zn2+ of Anaerobic Granular Sludge Acclimated by Flue Gas Pretreatment Wastewater

2013 ◽  
Vol 634-638 ◽  
pp. 182-186
Author(s):  
Juan Wang ◽  
Qin Zhong
Keyword(s):  
Flue Gas ◽  
Ph Value ◽  
Granular Sludge ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Anaerobic Granular Sludge ◽  
Methanogenic Activity ◽  
Activity Inhibition ◽  
Anaerobic Sludge Blanket

With the aim to use anaerobic granular sludge, the methanogenic activity inhibition and recovery of anaerobic granular sludge from an industrial anaerobic reactor (s1) were investigated by measuring the methane volume at low pH. A lab-scale upflow anaerobic sludge blanket (UASB) reactor was inoculated with s1.s1 was used to remove Zn2+ in wastewater. The results show that activity of s1 is similar when the pH value is 6.5 to 7.0. The methane volume is obviously decreased when the pH value is 6.0. The activity is completely inhibited when the pH value is 4.5. The activity is fully recovered when the pH is above 6.5 and hardly recovers when the pH fell to 4.5. The main Zn2+ removal mechanism is chemical adsorption.

Impact of microaeration bioreactor on dissolved sulfide and methane removal from real UASB effluent for sewage treatment

2020 ◽  
Vol 81 (9) ◽  
pp. 1951-1960 ◽  
Author(s):  
C. S. Cabral ◽  
A. L. Sanson ◽  
R. J. C. F. Afonso ◽  
C. A. L. Chernicharo ◽  
J. C. Araújo
Keyword(s):  
Sewage Treatment ◽  
Oxygen Demand ◽  
Post Treatment ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Sulfide Removal ◽  
Dissolved Sulfide ◽  
Removal Efficiencies ◽  
Anaerobic Sludge Blanket

Abstract Two bioreactors were investigated as an alternative for the post-treatment of effluent from an upflow anaerobic sludge blanket (UASB) reactor treating domestic sewage, aiming at dissolved sulfide and methane removal. The bioreactors (R-control and R-air) were operated at different hydraulic retention times (HRT; 6 and 3 h) with or without aeration. Large sulfide and methane removal efficiencies were achieved by the microaerated reactor at HRT of 6 h. At this HRT, sulfide removal efficiencies were equal to 61% and 79%, and methane removal efficiencies were 31% and 55% for R-control and R-air, respectively. At an HRT of 3 h, sulfide removal efficiencies were 22% (R-control) and 33% (R-air) and methane removal did not occur. The complete oxidation of sulfide, with sulfate formation, prevailed in both phases and bioreactors. However, elemental sulfur formation was more predominant at an HRT of 6 h than at an HRT of 3 h. Taken together, the results show that post-treatment improved the anaerobic effluent quality in terms of chemical oxygen demand and solids removal. However, ammoniacal nitrogen was not removed due to either the low concentration of air provided or the absence of microorganisms involved in the nitrogen cycle.

Toxicity and treatability of leachate: application of UASB reactor for leachate treatment from Okhla landfill, New Delhi

2012 ◽  
Vol 65 (10) ◽  
pp. 1887-1894 ◽  
Author(s):  
V. Singh ◽  
A. K. Mittal
Keyword(s):  
Oxygen Demand ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
New Delhi ◽  
Leachate Treatment ◽  
Feed Composition ◽  
Laboratory Scale Reactor ◽  
Anaerobic Sludge Blanket

This study reports applicability of upflow anaerobic sludge blanket (UASB) process to treat the leachate from a municipal landfill located in Delhi. A laboratory scale reactor was operated at an organic loading rate of 3.00 kg chemical oxygen demand (COD)/m3 d corresponding to a hydraulic retention time (HRT) of 12 h for over 8 months. The effect of toxicity of leachate, and feed composition on the treatability of leachate was evaluated. Average COD of the leachate, during the study period varied between 8,880 and 66,420 mg/l. Toxicity of the leachate used during a period of 8 months varied from LC50 1.22 to 12.35 for 96 h. The removal efficiency of soluble COD ranged between 91 and 67% for fresh leachate and decreased drastically from 90 to 35% for old leachate having high toxicity. The efficiency varied from 81 to 65%. The reactor performed more efficiently for the treatment of fresh leachate (less toxic, LC50 11.64, 12.35, and 12.15 for 96 h) as compared with old leachate (more toxic, LC50 1.22 for 96 h). Toxicity of the leachate affected its treatment potential by the UASB.

Advanced Reactor Design, Operation and Economy

1986 ◽  
Vol 18 (12) ◽  
pp. 99-108 ◽  
Author(s):  
Gatze Lettinga ◽  
Look Hulshoff Pol
Keyword(s):  
Suspended Solids ◽  
Granular Sludge ◽  
High Rate ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Internal Circulation ◽  
Inlet System ◽  
Anaerobic Sludge Blanket ◽  
Feed Inlet

Of the high rate anaerobic wastewater treatment systems the UASB (Upflow Anaerobic Sludge Blanket) reactor has found the widest application. Therefore the attention with respect to design, operation and economy will be focussed on this reactor type. In designing a UASB reactor specific attention is needed for the GSS (Gas-Solids Separator) device and the feed inlet system. For soluble wastewater generally no phase separation is required. Only for wastewaters high in suspended solids pre-acidification in a separate acidification reactor can be beneficial. Increasing attention is given to the development of modified UASB systems, such as a combination of a sludge bed reactor and an anaerobic filter. Other possible modified UASB systems may be found in a FS (Floating Settling) UASB reactor, the EGSB (Expanded Granular Sludge Bed) reactor and the UASB IC (Internal Circulation) reactor. As many factors are involved in the costs of a UASB reactor, only some rough data on reactor costs are presented.

Effect of micro-nutrients in anaerobic degradation of sulfate laden organics

2004 ◽  
Vol 31 (3) ◽  
pp. 420-431 ◽  
Author(s):  
S K Patidar ◽  
Vinod Tare
Keyword(s):  
Anaerobic Degradation ◽  
Oxygen Demand ◽  
Cod Removal ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Sulfide Concentration ◽  
Anaerobic Baffled Reactor ◽  
Sulfide Toxicity ◽  
Anaerobic Sludge Blanket

The effect of micro-nutrients, such as Fe, Ni, Zn, Co, and Mo, on anaerobic degradation of sulfate laden organics was investigated using bench-scale models of upflow anaerobic sludge blanket (UASB) reactor, anaerobic baffled reactor (ABR), and hybrid anaerobic baffled reactor (HABR), operating in varying conditions in ten phases (organic loading of 1.9–5.75 kg COD/(m3·d), sulfate loading of 0.54–1.88 kg SO42–/(m3·d), chemical oxygen demand (COD):SO42–ratio of 2.0–8.6). In the initial phase, no nutrient limitation was observed with COD removal of more than 94% in all three systems. Subsequently, increase in sulfate loading resulted in Ni and Co limitation and their supplementation restored COD removal in UASB system. However, baffled systems did not recover because of severe inhibition by sulfide. Results indicate that precipitation of nutrients could seriously deteriorate process performance, leading to failure even before sulfide concentration attains toxic level. The limitation of Fe coupled with high sulfate loading (1.88 kg SO42–/(m3·d)) resulted in growth of low-density, fragile, hollow, and granular biomass in UASB that washed out and caused process instability. Supplementation of Fe with other nutrients stabilized UASB process and also improved COD removal.Key words: anaerobic degradation, nutrients, UASB, ABR, HABR, sulfide toxicity, sulfate laden organics.

Mathematical modeling of upflow anaerobic sludge blanket (UASB) reactor treating domestic wastewater

2013 ◽  
Vol 67 (1) ◽  
pp. 24-32 ◽  
Author(s):  
Tarek Elmitwalli
Keyword(s):  
Chemical Oxygen Demand ◽  
Dynamic Model ◽  
Empirical Model ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Model Based ◽  
Anaerobic Sludge Blanket

Although the upflow anaerobic sludge blanket (UASB) reactor has been widely applied for domestic wastewater treatment in many developing countries, there is no sufficient mathematical model for proper design and operation of the reactor. An empirical model based on non-linear regression was developed to represent the physical and chemical removal of suspended solids (SS) in the reactor. Moreover, a simplified dynamic model based on ADM1 and the empirical model for SS removal was developed for anaerobic digestion of the entrapped SS and dissolved matter in the wastewater. The empirical model showed that effluent suspended chemical oxygen demand (CODss) concentration is directly proportional to the influent CODss concentration and inversely proportional to both the hydraulic retention time (HRT) of the reactor and wastewater temperature. For obtaining sufficient CODss removal, the HRT of the UASB reactor must be higher than 4 h, and higher HRT than 12 h slightly improved CODss removal. The dynamic model results showed that the required time for filling the reactor with sludge mainly depends on influent total chemical oxygen demand (CODt) concentration and HRT. The influent CODt concentration, HRT and temperature play a crucial role on the performance of the reactor. The results indicated that shorter HRT is needed for optimization of CODt removal, as compared with optimization of CODt conversion to methane. Based on the model results, the design HRT of the UASB reactor should be selected based on the optimization of wastewater conversion and minimization of biodegradable SS accumulation in the sludge bed, not only based on COD removal, to guarantee a stable reactor performance.

A downflow hanging sponge (DHS) reactor for faecal coliform removal from an upflow anaerobic sludge blanket (UASB) effluent

2015 ◽  
Vol 72 (11) ◽  
pp. 2034-2044 ◽  
Author(s):  
Rosa Elena Yaya Beas ◽  
Katarzyna Kujawa-Roeleveld ◽  
Jules B. van Lier ◽  
Grietje Zeeman
Keyword(s):  
Oxygen Demand ◽  
Faecal Coliform ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Loading Rates ◽  
Removal Capacity ◽  
Seed Crops ◽  
Anaerobic Sludge Blanket

This research was conducted to study the faecal coliforms removal capacity of downflow hanging sponge (DHS) reactors as a post-treatment for an upflow anaerobic sludge blanket (UASB) reactor. Three long-term continuous laboratory-scale DHS reactors, i.e. a reactor with cube type sponges without recirculation, a similar one with recirculation and a reactor with curtain type sponges, were studied. The porosities of the applied medium were 91%, 87% and 47% respectively. The organic loading rates were 0.86 kgCOD m−3 d−1, 0.53 kgCOD m−3 d−1 and 0.24 kgCOD m−3 d−1 correspondingly at hydraulic loading rates of 1.92 m3 m−2 d−1, 2.97 m3 m−2 d−1 and 1.32 m3 m−2 d−1, respectively (COD: chemical oxygen demand). The corresponding averages for faecal coliform removal were 99.997%, 99.919% and 92.121% respectively. The 1989 WHO guidelines standards, in terms of faecal coliform content for unrestricted irrigation (category A), was achieved with the effluent of the cube type DHS (G1) without recirculation. Restricted irrigation, category B and C, is assigned to the effluent of the cube type with recirculation and the curtain type, respectively. Particularly for organic compounds, the effluent of evaluated DHS reactors complies with USEPA standards for irrigation of so called non-food crops like pasture for milking animals, fodder, fibre, and seed crops.

Impact of aluminum chloride on process performance and microbial community structure of granular sludge in an upflow anaerobic sludge blanket reactor for natural rubber processing wastewater treatment

2016 ◽  
Vol 74 (2) ◽  
pp. 500-507 ◽  
Author(s):  
Nguyen Thi Thanh ◽  
Takahiro Watari ◽  
Tran Phuong Thao ◽  
Masashi Hatamoto ◽  
Daisuke Tanikawa ◽  
...  
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Natural Rubber ◽  
Microbial Community Structure ◽  
Aluminum Chloride ◽  
Granular Sludge ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Anaerobic Sludge Blanket

In this study, granular sludge formation was carried out using an aluminum chloride supplement in an upflow anaerobic sludge blanket (UASB) reactor treating natural rubber processing wastewater. Results show that during the first 75 days after the start-up of the UASB reactor with an organic loading rate (OLR) of 2.65 kg-COD·m−3·day−1, it performed stably with a removal of 90% of the total chemical oxygen demand (COD) and sludge still remained in small dispersed flocs. However, after aluminum chloride was added at a concentration of 300 mg·L−1 and the OLR range was increased up to 5.32 kg-COD·m−3·day−1, the total COD removal efficiency rose to 96.5 ± 2.6%, with a methane recovery rate of 84.9 ± 13.4%, and the flocs began to form granules. Massively parallel 16S rRNA gene sequencing of the sludge retained in the UASB reactor showed that total sequence reads of Methanosaeta sp. and Methanosarcina sp., reported to be the key organisms for granulation, increased after 311 days of operation. This indicates that the microbial community structure of the retained sludge in the UASB reactor at the end of the experiment gave a good account of itself in not only COD removal, but also granule formation.

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.

scholarly journals Black water treatment by an upflow anaerobic sludge blanket (UASB) reactor: a pilot study

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
Keyword(s):  
Removal Efficiency ◽  
Phase 1 ◽  
Oxygen Demand ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
Phase 3 ◽  
Black Water ◽  
Anaerobic Sludge Blanket

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.

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