Anaerobic treatment of wastewater with high suspended solids from a bulk drug industry using fixed film reactor (AFFR)

Three laboratory model anaerobic fixed film reactors, AFFR-A, B, and C, fed by a pretreated leachate, were monitored at 35 ± 5 °C for 10 months to estimate the effects of different concentrations and the forms of phosphate (ortho, organic, or condensed) on performances at 1.2–1.8 g COD/(d∙L) of reactor volume. Ortho phosphate (Na3PO4) supplement was added to the feed of AFFR-A, organic phosphate (sodium glycerophosphate: C3H7Na2O6P∙5H2O) to AFFR-B, and condensed phosphate (Na4P2O7) to AFFR-C at a feed COD/P value of about 6100 for 23 weeks (Phase I). When no PO4 deficiency was observed, the value was increased to 7700 in reactors A and B, but the PO4 supplement was terminated for reactor C, resulting in a value of 64 300 (Phase II). The average COD of C effluent was 599 mg/L as compared to 451 and 442 mg/L for reactors A and B, respectively, suggesting that a COD/P of 64 300 was too high. During Phase III, the COD/P ratios were changed in reactors A, B, and C, respectively, to 10 200, 15 200, and 34 300. The results indicate that the "optimal" ratio of COD/P lies perhaps between 15 000 and 34 300. Anaerobes did not prefer any one form of PO4 over the other two. Key words: anaerobic treatment, phosphate requirement, ortho phosphate, condensed phosphate, organic phosphate, leachate treatment, fixed film reactor.

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Anaerobic treatment of beet waste in a stationary fixed-film reactor

Agricultural Wastes ◽

10.1016/0141-4607(86)90092-2 ◽

1986 ◽

Vol 17 (3) ◽

pp. 175-187 ◽

Cited By ~ 6

Author(s):

M.F. Hamoda ◽

K.J. Kennedy

Keyword(s):

Anaerobic Treatment ◽

Fixed Film ◽

Film Reactor

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Anaerobic Treatment of a Petrochemical Wastewater from a Terephthalic Acid Plant

Water Science & Technology ◽

10.2166/wst.1992.0154 ◽

1992 ◽

Vol 25 (7) ◽

pp. 223-235 ◽

Cited By ~ 55

Author(s):

H. Macarie ◽

A. Noyola ◽

J. P. Guyot

Keyword(s):

Activated Sludge ◽

Terephthalic Acid ◽

Treatment Plant ◽

Tubular Reactor ◽

Anaerobic Treatment ◽

Cod Removal ◽

Acid Plant ◽

Aerobic Process ◽

Fixed Film ◽

Film Reactor

Anaerobic treatment of terephthalic acid plant wastewater was tested using two UASB reactors (T and U) and a downflow tubular fixed film reactor. UASB T was inoculated with sludge sampled from an anaerobic stabilization pond receiving waste activated sludge from a petrochemical industry treatment plant. UASB U and the fixed film reactor were inoculated with anaerobically adapted activated sludge from a municipal plant. Raw effluent had to be settled and neutralized before reactor feeding. Sedimentation resulted in 70% TSS and 37% COD removal. UASB digesters presented comparable treatment efficiencies with rather low COD removals: the best results were 46.4% for UASB T at 2.6 kg COD/m3.d and a hydraulic retention time (θ) of 2.7 days and 43.9% for UASB U at 2.2 kg COD/m3.d and θ of 3.2 days. The performance of the tubular reactor was much higher, 74.5% COD removal at 1.89 kg/m3.d and θ of 3.4 days. The better efficiencies of this last digester are explained mainly by a higher VSS content and a better resistance to toxicity caused by the aromatics present in the wastewater. A primary settling-anaerobic-aerobic process is proposed as an alternative to the conventional aerobic process for treating terephthalic wastewater, but disposal of solids from primary sedimentation and cost of neutralization have to be considered before application.

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Anaerobic treatment of domestic sewage with a rotating stationary fixed-film reactor

Water Research ◽

10.1016/0043-1354(88)90172-8 ◽

1988 ◽

Vol 22 (12) ◽

pp. 1585-1592 ◽

Cited By ~ 35

Author(s):

A. Noyola ◽

B. Capdeville ◽

H. Roques

Keyword(s):

Anaerobic Treatment ◽

Domestic Sewage ◽

Fixed Film ◽

Film Reactor

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Anaerobic treatment of a municipal landfill leachate

Canadian Journal of Microbiology ◽

10.1139/m97-135 ◽

1997 ◽

Vol 43 (10) ◽

pp. 937-944 ◽

Cited By ~ 2

Author(s):

Jean-Claude Frigon ◽

Jean-Guy Bisaillon ◽

Gilles Paquette ◽

Réjean Beaudet

Keyword(s):

Landfill Leachate ◽

Growth Parameters ◽

Oxygen Demand ◽

Anaerobic Treatment ◽

Cod Removal ◽

Organic Loading Rate ◽

Oil And Grease ◽

Municipal Landfill ◽

Fixed Film ◽

Film Reactor

Leachate from a municipal landfill site was treated in a laboratory using fixed-film cultures under anaerobic conditions. Serum-bottle cultures were used for optimization of the growth parameters. The reduction of the chemical oxygen demand (COD) of the leachate was faster at 29 °C compared with lower temperatures. Gradual acclimation of the microbial population to temperatures as low as 4 °C considerably increased the rate of COD removal at these temperatures. Addition of supplements to the leachate was not needed and it was not necessary to adjust the pH (5.9) for optimal COD reduction. Continuously fed reactors were also used to treat the leachate. The maximum organic loading rate of the reactor at 22 °C to obtain 85% COD removal was 2.1 kg COD∙m−3∙day−1, which corresponded to an hydraulic retention time of 1.5 days. After treatment under these conditions, the toxicity (Microtox method) of the leachate was completely eliminated and the required quality standards were met for iron, oil and grease, and phenols. The fermentative microorganisms in the biofilm of the reactor were evaluated to 4.6 × 107cells∙cm−2and identified as Streptococcus gallinarum, Clostridium glycolicum, Clostridium bifermentans or sadallii, Citrobacter amalonaticus, Bacteroides capillosus, and Eubacterium sp.Key words: anaerobic treatment, landfill, leachate, growth parameters, fixed-film reactor, microbiology.

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Starting-Up of an Anaerobic Fixed-Film Reactor

Water Science & Technology ◽

10.2166/wst.1983.0173 ◽

1983 ◽

Vol 15 (8-9) ◽

pp. 305-308 ◽

Cited By ~ 44

Author(s):

M S Salkinoja-Salonen ◽

E.-J Nyns ◽

P M Sutton ◽

L van den Berg ◽

A D Wheatley

Keyword(s):

Fixed Film ◽

Film Reactor

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Vacuum Operation for Overloaded Anaerobic Treatment Systems

Water Science & Technology ◽

10.2166/wst.1989.0213 ◽

1989 ◽

Vol 21 (4-5) ◽

pp. 87-95

Author(s):

J. De Santis ◽

A. A. Friedman

Keyword(s):

Volatile Fatty Acids ◽

Loading Rate ◽

Anaerobic Treatment ◽

Optimum Operating ◽

Operating Pressure ◽

Simple Modification ◽

Anaerobic Reactors ◽

Fixed Film ◽

Solids Retention ◽

High Concentrations

Overloaded anaerobic treatment systems are characterized by high concentrations of volatile fatty acids and molecular hydrogen and poor conversion of primary substrates to methane. Previous experiments with fixed–film reactors indicated that operation with reduced headspace pressures enhanced anaerobic treatment. For these studies, four suspended culture, anaerobic reactors were operated with headspace pressures maintained between 0.5 and 1.0 atm and a solids retention time of 15 days. For lightly loaded systems (0.4 g SCOD/g VSS-day) vacuum operation provided minor treatment improvements. For shock organic loads, vacuum operation proved to be more stable and to support quicker recovery from upset conditions. Based on these studies and a companion set of bioassay tests, it was concluded that: (a) a loading rate of about 1.0 g SCOD/g VSS-day represents a practical loading limit for successful anaerobic treatment, (b) a headspace pressure of approximately 0.75 atm appears to be an optimum operating pressure for anaerobic systems and (c) simple modification to existing systems may provide relief for organically overloaded systems.

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Tertiary nitrification in pilot-plant plug-flow fixed-film reactors with long-term ammonium deficiency

Water Science & Technology ◽

10.2166/wst.1994.0746 ◽

1994 ◽

Vol 29 (10-11) ◽

pp. 61-67 ◽

Cited By ~ 2

Author(s):

M. Fruhen ◽

K. Böcker ◽

S. Eidens ◽

D. Haaf ◽

M. Liebeskind ◽

...

Keyword(s):

Pilot Plant ◽

Effective Means ◽

Plug Flow ◽

Nitrification Rate ◽

Industrial Project ◽

Transfer Processes ◽

Fixed Film ◽

Film Reactor ◽

Observation Period

The objective of this study is to investigate to what extent the nitrification capacity of a pilot-plant fixed-film reactor changes during extensive periods of nutrient supply deficiency. The examined pilot-plant was an upflow reactor filled with swelling clay of medium grain size (6 to 8 mm). The experiments revealed that the maximum nitrification rate remained practically constant during the first weeks after the onset of unregulated ammonium supply. The capacity declined slowly, dropping to approximately 66% of the initial capacity after about ten weeks. Still ammonium peaks of up to 8 mg/l were readily nitrified throughout the entire period of the experiment. The reduction in nitrification capacity during the observation period did not result from decay processes of biomass but from the reactor becoming blocked and thus hampering transfer processes. It could be observed that the detached organisms attached again further up. This semi-industrial project demonstrated that a plug-flow fixed-film reactor can be used as effective means of tertiary nitrification.

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Nitrate removal from water supplies using biodenitrification and GAC-sand filter systems

Water Science & Technology ◽

10.2166/wst.1994.0462 ◽

1994 ◽

Vol 30 (9) ◽

pp. 133-139 ◽

Cited By ~ 15

Author(s):

M. F. Dahab ◽

S. Sirigina

Keyword(s):

Activated Carbon ◽

Suspended Solids ◽

Nitrate Removal ◽

Total Suspended Solids ◽

Water Supply Systems ◽

Water Supplies ◽

Sand Filter ◽

Fixed Film ◽

Supply Systems ◽

The U.S

In this paper, a study on using fixed-film biological denitrification to remove nitrates from water supplies is reported. Fixed-film biological systems have not been used in water supply systems in the U.S. although they are proven to be efficient and economical for removing nitrates with the reason being the possibility of imparting residual organics, suspended solids and bacteria to the treated water. In this research, fixed-film upflow biodenitrification columns were operated under carbon-starved conditions and the effluent was treated with a granular activated carbon (GAC) and sand filter system (combined in one unit) to remove residual organics and suspended matter. The system resulted in an average effluent turbidity of 0.8 NTU, and COD and total suspended solids (TSS) concentrations of 5.7 and 0.6 mg/L, respectively.

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