Evaluation of Alternatives to Conventional Disc Support Media for Rotating Biological Contactors

A variety of biofilm support media for rotating biological contactors, both aerobic and anaerobic. are reviewed in the light of experience gained from laboratory. pilot-scale and full-scale operations. Currently there is no clear economically superior replacement for conventional HDPE moulded discs for aerobic treatment plants. As little anaerobic full-scale operational work has been carried out it has been speculated that random-packed media and twin-walled polycarbonate sheets could provide a substitute support material in anaerobic treatment units.

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Anaerobic and Aerobic Treatment for AOX Removal

Water Science & Technology ◽

10.2166/wst.1994.0710 ◽

1994 ◽

Vol 29 (5-6) ◽

pp. 149-162 ◽

Cited By ~ 7

Author(s):

John F. Ferguson

Keyword(s):

Biological Treatment ◽

Anaerobic Treatment ◽

Reductive Dehalogenation ◽

Aerobic Treatment ◽

Abiotic Degradation ◽

In Series ◽

Kraft Mill ◽

Significant Chemical ◽

Aox Removal ◽

Aerobic And Anaerobic

A two-year study has focused on AOX removal from bleaching wastewaters in anaerobic and aerobic biological treatment, using bench scale bioreactors operated in parallel and in series. Significantly higher removals have been found in anaerobic than in aerobic treatment. Earlier work with dilute kraft bleaching wastes has been extended in additional laboratory tests and at a nearby kraft mill. 50-75% fractions of bleaching wastes were treated. Toxicity in the anaerobic process was encountered at 85% bleach waste fractions. Total AOX removal experienced in aerobic treatment is 30-35%, in anaerobic treatment 40-45%, and in an anaerobic/aerobic sequence 50-55%. Percentage removals were not sensitive to the fraction of bleaching wastewater. Several process modifications were attempted to try to obtain higher removals with only marginal success. Studies at a kraft mill confirmed the AOX removals that had been found in lab studies. AOX removal occurs by several mechanisms. There is a very significant chemical or abiotic degradation that occurs after neutralization, perhaps enhanced by reductants or other inorganic salts. Biological processes are much more significant in anaerobic than in aerobic treatment. Anaerobic reductive dehalogenation affects specific chlorinated compounds and catalyzed AOX degradation is facilitated by reduced coenzymes that are produced by bacteria. Removal by sorption or insolubilization is relatively minor in aerobic and anaerobic processes.

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Anaerobic-Aerobic Treatment of Industrial Wastewater

Water Science & Technology ◽

10.2166/wst.1988.0166 ◽

1988 ◽

Vol 20 (4-5) ◽

pp. 189-198 ◽

Cited By ~ 3

Author(s):

H. Bode

Keyword(s):

Experimental Work ◽

Industrial Wastewater ◽

Sugar Industry ◽

Anaerobic Treatment ◽

Full Scale ◽

The Other ◽

Aerobic Treatment ◽

Industrial Wastewaters ◽

Pulp Industry ◽

Aerobic Process

The paper evaluates the question of whether a combined anaerobic-aerobic or a solely aerobic treatment of some particular industrial wastewaters leads to better results. Therefore three different industrial wastewaters were treated in two different process lines: one line consisted of anaerobic treatment prior to aerobic treatment and in the other, only aerobic treatment was applied. The experiments were run with wastewater from:–the pectin industry–the sugar industry (beet sugar)–the animal pulp industry. The data presented in this paper were gained from experimental work which was conducted over a period of two years. Different scales of treatment plants were used. The anaerobic treatment was done in full- and semitechnical scale reactors, while the aerobic treatment took place in labscale and semitechnical scale plants. Surprisingly in all three cases the solely aerobic treatment led to slightly better results in terms of residual pollution. Finally the paper presents data gained from a recently built, full-scale anaerobic-aerobic process which treats pectin waste. The aerobic stage of the process was designed on the basis of the results from the experimental work which was mentioned above. The results from the former experimental work and from the full-scale operation are compared.

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Anaerobic Treatment of Fibre Board Mill Wastewater

Water Science & Technology ◽

10.2166/wst.1985.0026 ◽

1985 ◽

Vol 17 (1) ◽

pp. 307-311 ◽

Cited By ~ 4

Author(s):

H Kroiss ◽

K Svardal

Keyword(s):

Pilot Scale ◽

Anaerobic Treatment ◽

Aerobic Treatment ◽

Pollution Load ◽

Removal Efficiencies ◽

Very High

The specific pollution load per ton of fibre board at an Austrian factory is in the range of 110 kg COD or 50 kg BOD5. Aerobic treatment would result in unacceptable costs (energy, nutrients, sludge handling). Semitechnical pilot scale investigations showed that anaerobic treatment can lower the BOD5 to about 80 % and the COD to about 75 %. But it was not possible to maintain these efficiencies over longer periods (several months). Labscale experiments resulted in stable and very high removal efficiencies (94 % BOD5, 86 % COD). Reliable neutralization was shown to be necessary for good results.

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Bacterial Population Dynamics in Dairy Waste during Aerobic and Anaerobic Treatment and Subsequent Storage

Applied and Environmental Microbiology ◽

10.1128/aem.01422-06 ◽

2006 ◽

Vol 73 (1) ◽

pp. 193-202 ◽

Cited By ~ 36

Author(s):

Jeffery A. McGarvey ◽

William G. Miller ◽

Ruihong Zhang ◽

Yanguo Ma ◽

Frank Mitloehner

Keyword(s):

Population Dynamics ◽

Population Structure ◽

Bacterial Population ◽

Oxygen Demand ◽

Anaerobic Treatment ◽

Rrna Gene ◽

Aerobic Treatment ◽

Dairy Waste ◽

Subsequent Storage ◽

Aerobic And Anaerobic

ABSTRACT The objective of this study was to model a typical dairy waste stream, monitor the chemical and bacterial population dynamics that occur during aerobic or anaerobic treatment and subsequent storage in a simulated lagoon, and compare them to those of waste held without treatment in a simulated lagoon. Both aerobic and anaerobic treatment methods followed by storage effectively reduced the levels of total solids (59 to 68%), biological oxygen demand (85 to 90%), and sulfate (56 to 65%), as well as aerobic (83 to 95%), anaerobic (80 to 90%), and coliform (>99%) bacteria. However, only aerobic treatment reduced the levels of ammonia, and anaerobic treatment was more effective at reducing total sulfur and sulfate. The bacterial population structure of waste before and after treatment was monitored using 16S rRNA gene sequence libraries. Both treatments had unique effects on the bacterial population structure of waste. Aerobic treatment resulted in the greatest change in the type of bacteria present, with the levels of eight out of nine phyla being significantly altered. The most notable differences were the >16-fold increase in the phylum Proteobacteria and the approximately 8-fold decrease in the phylum Firmicutes. Anaerobic treatment resulted in fewer alterations, but significant decreases in the phyla Actinobacteria and Bacteroidetes, and increases in the phyla Planctomycetes, Spirochetes, and TM7 were observed.

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Electrical Conductivity for Monitoring the Expansion of the Support Material in an Anaerobic Biofilm Reactor

Processes ◽

10.3390/pr8010077 ◽

2020 ◽

Vol 8 (1) ◽

pp. 77 ◽

Cited By ~ 1

Author(s):

Oscar Marín-Peña ◽

Alejandro Alvarado-Lassman ◽

Norma A. Vallejo-Cantú ◽

Isaías Juárez-Barojas ◽

José Pastor Rodríguez-Jarquín ◽

...

Keyword(s):

Electrical Conductivity ◽

Volatile Fatty Acids ◽

Liquid Fraction ◽

Detection System ◽

Pilot Scale ◽

Anaerobic Treatment ◽

Biofilm Reactor ◽

Support Material ◽

Inverse Fluidized Bed ◽

Bed Expansion

This article describes the use of the electrical conductivity for measuring bed expansion in a continuous anaerobic biofilm reactor in order to prevent the exit of support material from the reactor with the consequent loss of biomass. The substrate used for the tests is obtained from a two-stage anaerobic digestion (AD) process at the pilot scale that treats the liquid fraction of fruit and vegetable waste (FVW). Tests were performed with the raw substrate before anaerobic treatment (S1), the effluent from the hydrolysis reactor (S2), and the effluent from the methanogenic reactor (S3) to evaluate its effect on the electrical conductivity values and its interaction with colonized support material. The tests were carried out in a 32 L anaerobic inverse fluidized bed reactor (IFBR), which was inoculated with colonized support material and using two industrial electrodes at different column positions. The results with the previously digested samples (S2 and S3) were satisfactory to detect the presence of support material at the points where the electrodes were placed since the electrical conductivity values showed significant changes of up to 0.5 V, while with substrate S1 no significant voltage differences were appreciated. These results demonstrate that electrical conductivity can be used as an economic and simple mean for monitoring the support material expansion in order to avoid over expansion in the IFBR. It was also demonstrated that the conditions of the substrate in the methanogenic stage (pH and presence of volatile fatty acids) do not affect the operation of the electrical conductivity detection system.

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The use of algal-bacterial biofilms to enhance nitrification rates in lagoons: experience under laboratory and pilot-scale conditions

Water Science & Technology ◽

10.2166/wst.2000.0639 ◽

2000 ◽

Vol 42 (10-11) ◽

pp. 187-194 ◽

Cited By ~ 11

Author(s):

B. M. McLean ◽

K. Baskaran ◽

M. A. Connor

Keyword(s):

Treatment Plant ◽

Pilot Scale ◽

Ammonia Removal ◽

Nitrifying Bacteria ◽

Bacterial Biofilms ◽

Support Material ◽

Removal Rates ◽

Support Surfaces ◽

Biofilm Support ◽

Lagoon Systems

Investigations were undertaken at the Western Treatment Plant (WTP), near Melbourne, Australia, to find ways of increasing overall ammonia and nitrogen removal rates in the WTP lagoon systems. Immobilisation of nitrifying bacteria in biofilms was one approach explored. Preliminary tests showed that algal/bacterial biofilms capable of achieving ammonia removal rates of 3 to 4 μg N/cm2·h would form on support surfaces immersed in the WTP lagoons. A laboratory-scale investigation was carried out to characterise the influence of parameters such as pH, temperature, COD level, dissolved oxygen concentration and incubation depth on biofilm performance. This study was followed by a pilot-scale investigation in a series of experimental ponds at the WTP. This compared the performance of three ponds, two containing 9360 m2 and 18240 m2 respectively of a geotextile biofilm support material and one containing no biofilm support material (the control pond). Ammonia removal rates comparable to those obtained in the preliminary tests were obtained when the biofilm support material was within the top 500 mm of the lagoon, i.e. in the photic zone. COD and suspended solids levels in the effluents from the biofilm containing ponds were substantially lower than those in the control pond effluent.

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Heating up trickling filters to tackle cold weather conditions

Water Science & Technology ◽

10.2166/wst.2000.0025 ◽

2000 ◽

Vol 41 (1) ◽

pp. 163-166 ◽

Cited By ~ 3

Author(s):

W. Gebert ◽

P.A. Wilderer

Keyword(s):

Waste Heat ◽

Treatment Plant ◽

Weather Conditions ◽

Pilot Scale ◽

Cold Weather ◽

Filling Material ◽

Trickling Filter ◽

Biofilm Thickness ◽

Trickling Filters ◽

Biofilm Support

The investigated effects of heating the filling material in trickling filters were carried out at the Ingolstadt wastewater treatment plant, Germany. Two pilot scale trickling filters were set up. Heat exchanger pipings were embedded in the filter media of one of these trickling filters, and the temperature in the trickling filter was raised. The other trickling filter was operated under normal temperature conditions, and was used as a control. The results clearly demonstrate that the performance of trickling filters cannot be constantly improved by heating the biofilm support media. A sustained increase of the metabolic rates did not occur. The decrease of the solubility of oxgen in water and mass transfer limitations caused by an increase of the biofilm thickness are the main reasons for that. Thus, the heating of trickling filters (e.g. by waste heat utilization) in order to increase the capacity of trickling filters under cold weather conditions cannot be recommended.

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Biotransformation of nitrocellulose under methanogenic conditions

Water Science & Technology ◽

10.2166/wst.1996.0567 ◽

1996 ◽

Vol 34 (5-6) ◽

pp. 327-334 ◽

Cited By ~ 2

Author(s):

David L. Freedman ◽

Bryan M. Caenepeel ◽

Byung J. Kim

Keyword(s):

Biological Treatment ◽

Enrichment Culture ◽

Basal Medium ◽

Anaerobic Biodegradation ◽

Anaerobic Treatment ◽

Acid Digestion ◽

Energetic Compounds ◽

Nitrate Ester ◽

Digestion Technique ◽

Aerobic And Anaerobic

Treatment of wastewater containing nitrocellulose (NC) fines is a significant hazardous waste problem currently facing manufacturers of energetic compounds. Previous studies have ruled out the use of biological treatment, since NC has appeared to be resistant to aerobic and anaerobic biodegradation. The objective of this study was to examine NC biotransformation in a mixed methanogenic enrichment culture. A modified cold-acid digestion technique was used to measure the percentage of oxidized nitrogen (N) remaining on the NC. After 11 days of incubation in cultures amended with NC (10 g/L) and methanol (9.9 mM), the % N (w/w) on the NC decreased from 13.3% to 10.1%. The presence of NC also caused a 16% reduction in methane output. Assuming the nitrate ester on NC was reduced to N2, the decrease in CH4 represented almost exactly the amount of reducing equivalents needed for the observed decrease in oxidized N. An increase in the heat of combustion of the transformed NC correlated with the decrease in % N. There was no statistically significant decrease in % N when only NC was added to the culture, or in controls that contained only the sulfide-reduced basal medium. The biotransformed NC has a % N comparable to nonexplosive nitrated celluloses, suggesting that anaerobic treatment may be a technically feasible process for rendering NC nonhazardous.

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Enhancing nitrogen removal efficiency in a dyestuff wastewater treatment plant with the IFFAS process: the pilot-scale and full-scale studies

Water Science & Technology ◽

10.2166/wst.2017.522 ◽

2017 ◽

Vol 77 (1) ◽

pp. 70-78 ◽

Cited By ~ 4

Author(s):

Yanjun Mao ◽

Xie Quan ◽

Huimin Zhao ◽

Yaobin Zhang ◽

Shuo Chen ◽

...

Keyword(s):

Wastewater Treatment ◽

Activated Sludge ◽

Removal Efficiency ◽

Nitrogen Removal ◽

Treatment Plant ◽

Oxygen Demand ◽

Pilot Scale ◽

Full Scale ◽

Nitrification And Denitrification ◽

Dyestuff Wastewater

Abstract The activated sludge (AS) process is widely applied in dyestuff wastewater treatment plants (WWTPs); however, the nitrogen removal efficiency is relatively low and the effluent does not meet the indirect discharge standards before being discharged into the industrial park's WWTP. Hence it is necessary to upgrade the WWTP with more advanced technologies. Moving bed biofilm processes with suspended carriers in an aerobic tank are promising methods due to enhanced nitrification and denitrification. Herein, a pilot-scale integrated free-floating biofilm and activated sludge (IFFAS) process was employed to investigate the feasibility of enhancing nitrogen removal efficiency at different hydraulic retention times (HRTs). The results showed that the effluent chemical oxygen demand (COD), ammonium nitrate (NH4+-N) and total nitrogen (TN) concentrations of the IFFAS process were significantly lower than those of the AS process, and could meet the indirect discharge standards. PCR-DGGE and FISH results indicated that more nitrifiers and denitrifiers co-existed in the IFFAS system, promoting simultaneous nitrification and denitrification. Based on the pilot results, the IFFAS process was used to upgrade the full-scale AS process, and the effluent COD, NH4+-N and TN of the IFFAS process were 91–291 mg/L, 10.6–28.7 mg/L and 18.9–48.6 mg/L, stably meeting the indirect discharge standards and demonstrating the advantages of IFFAS in dyestuff wastewater treatment.

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