Anaerobic and Aerobic Treatment for AOX Removal

1994 ◽  
Vol 29 (5-6) ◽  
pp. 149-162 ◽  
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.

Biotransformation of nitrocellulose under methanogenic conditions

1996 ◽  
Vol 34 (5-6) ◽  
pp. 327-334 ◽  
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.

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

1990 ◽  
Vol 22 (1-2) ◽  
pp. 113-117 ◽  
Author(s):  
A. J. Ware ◽  
M. B. Pescod ◽  
B. Storch
Keyword(s):  
Pilot Scale ◽  
Anaerobic Treatment ◽  
Full Scale ◽  
Aerobic Treatment ◽  
Support Material ◽  
Rotating Biological Contactors ◽  
Biofilm Support ◽  
Aerobic And Anaerobic

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.

Anaerobic-Aerobic Lagoon Treatment of Kraft Mill Effluent for Enhanced Removal of AOX

1993 ◽  
Vol 28 (3) ◽  
pp. 549-570 ◽  
Author(s):  
E.G.-H. Lee ◽  
M.F. Crowe ◽  
H. Stutz
Keyword(s):  
Treatment Process ◽  
Pilot Scale ◽  
Aerobic Treatment ◽  
Simple Modification ◽  
Kraft Mill Effluent ◽  
Kraft Mill ◽  
Removal Efficiencies ◽  
Adsorbable Organic Halide ◽  
Aox Removal ◽  
Kraft Effluent

Abstract A continuous-flow sequential anaerobic-aerobic lagoon treatment process was developed and evaluated for removal of adsorbable organic halide (AOX) from whole-mill kraft effluent at both laboratory and pilot-scale. The rationale underlying the development of the process was that the AOX removal efficiency of aerated lagoons currently in use might be significantly increased through relatively simple modification. Bench-scale studies showed that sequential anaerobic-aerobic treatment of whole-mill kraft effluent resulted in AOX-removal efficiencies of over 70% at hydraulic retention times (HRTs) of 10 days, 5 days and 2 days. In contrast, only 20%, 35% and 36% removal was obtained in a control aerobic lagoon. Pilot-scale studies showed that up to 65% removal of AOX from whole-mill kraft effluent was consistently obtained at HRTs ranging from 5 to 10 days. This compares with typical AOX removal efficiencies in conventional aerated lagoons of about 25%. Conversion of the anaerobic section in the pilot-scale lagoon from a simple sludge blanket to a combination of sludge blanket and submerged biofilm further increased AOX removal efficiencies to about 70%.

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

2006 ◽  
Vol 73 (1) ◽  
pp. 193-202 ◽  
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.

AOX Removal from Bleached Kraft Mill Wastewater: A Comparison of Three Biological Treatment Processes

1992 ◽  
Vol 26 (1-2) ◽  
pp. 387-396 ◽  
Author(s):  
E. R. Hall ◽  
W. G. Randle
Keyword(s):  
Biological Treatment ◽  
Operating Conditions ◽  
Gas Stripping ◽  
Treatment Processes ◽  
Organic Halogen ◽  
System Data ◽  
Kraft Mill ◽  
Removal Efficiencies ◽  
Comparison Of The Results ◽  
Aox Removal

Laboratory scale activated sludge (AS), facultative stabilization basin (FSB) and aerated stabilization basin (ASB) processes were operated under controlled parallel conditions to assess the AOX (adsorbable organic halogen) removal efficiencies attainable in each. A comparison of the results obtained under a variety of operating conditions indicated that higher removal efficiencies of total and filterable AOX were achieved in the FSB and ASB processes than in the AS system. Data are also presented to indicate the extent to which influent AOX was removed by biodegradation, biosorption and off-gas stripping.

Soluble microbial product formation during biological treatment of fermentation industry effluent

2000 ◽  
Vol 42 (1-2) ◽  
pp. 111-116 ◽  
Author(s):  
O. Goorany ◽  
I. Oztürk
Keyword(s):  
Molecular Weight ◽  
Biological Treatment ◽  
High Strength ◽  
Anaerobic Treatment ◽  
Product Formation ◽  
Microbial Product ◽  
Treatment Processes ◽  
Industry Effluent ◽  
Aerobic And Anaerobic ◽  
Raw Wastewater

The most important factor that affects the quality of effluents and overall organic matter removal in biological treatment processes is the presence of soluble microbial products (SMP) that are produced during biological treatment and remain in effluent. High strength wastewater from fermentation industry (FIE) was used as a slowly degradable substrate to investigate SMP formation in aerobic and anaerobic treatment. For SMP determination which forms a major part of residual soluble COD of the wastewater, the initial inert soluble COD (SI) was determined. It was found that SI/So is 0.122 and 0.164 for aerobic and anaerobic processes, respectively. During aerobic treatment of FIE for initialCOD (So) values varying between 1540–6645 mg COD/L, SMP are expected to vary within the range of 12.5–8.6% of So, respectively. In anaerobic treatment of the FIE, for values of 2670–6585 mg COD/L, SMP are expected to vary within the range of 9.8–6.2% of So, respectively. Molecular weight distribution analyses of raw wastewater, aerobic and anaerobic treatment effluent indicate that in both systems the effluent of FIE presents similar molecular weight fractions and are very high compared to raw wastewater.

Pollution loads and inert COD in the laying chicken industry

1999 ◽  
Vol 40 (1) ◽  
pp. 207-213
Author(s):  
F. Germirli Babuna ◽  
E. Çekyay ◽  
G. Eremektar ◽  
D. Orhon
Keyword(s):  
Biological Treatment ◽  
Anaerobic Treatment ◽  
Organic Load ◽  
Residual Fraction ◽  
Aerobic Treatment ◽  
High Nitrogen ◽  
Nitrogen And Phosphorus ◽  
Intermittent Mode ◽  
As Toxicity ◽  
Pollution Loads

Modern laying chicken plants generate strong wastewaters of limited flow rate, with COD concentrations up around to 10 g l−1, with a soluble portion of 50% and high nitrogen and phosphorus contents. The unit wastewater flow is as low as 0.003-0.005 1 chicken−1 day−1 and the unit organic load is assessed as 0.03 g COD chicken−1 day−1. COD fractionation reveals that the soluble residual portion accounts for 350 mg l−1 in the chicks step and 980 mg l−1 in the laying step for aerobic treatment. When anaerobic treatment is applied this residual fraction is likely to exhibit an increase of around 60 to 80 %. These observations underline the significance and the need of setting effluent limitations attainable by biological treatment, if evidence is presented that they do not pose appreciable environmental problems such as toxicity, colour, etc. This is especially true for laying chicken plant effluents, due to their intermittent mode of generation and their limited volume.

Combined Anaerobic/Aerobic Treatment of Peroxide Bleached TMP Mill Effluent

1994 ◽  
Vol 29 (5-6) ◽  
pp. 381-389 ◽  
Author(s):  
W. J. B. M. Driessen ◽  
C.-O. Wasenius
Keyword(s):  
Biological Treatment ◽  
Pulp Mill ◽  
Anaerobic Treatment ◽  
Aerobic Treatment ◽  
Pulp And Paper Mills ◽  
Paper Mills ◽  
Loading Rates ◽  
Volumetric Loading ◽  
Extensive Pilot

In this paper combined anaerobic/aerobic treatment is illustrated by two examples at integrated pulp and paper mills with peroxide bleached TMP pulp production. The concept of combined biological treatment is to treat the more polluted effluents from the TMP pulp mill in an anaerobic reactor and subsequently to mix them with the less concentrated effluent, for treatment by an aerobic process. Extensive pilot research was done to confirm the feasibility of anaerobic treatment of peroxide bleached TMP mill effluent COD removal efficiencies of 55-60% were achieved at volumetric loading rates of up to 20 kg/m3/d. Possible toxic effects from peroxide could easily be neutralized by removal in a preacidification tank. Long term full scale experience proved that combined anaerobic aerobic treatment is an attractive and reliable method for treatment of peroxide bleached TMP mill effluent.

scholarly journals Biological treatment of whey in an UASFF bioreactor followed a three-stage RBC

2010 ◽  
Vol 16 (2) ◽  
pp. 175-182 ◽  
Author(s):  
Atiye Ebrahimi ◽  
Ghasem Najafpour ◽  
Maedeh Mohammadi ◽  
Babak Hashemiyeh
Keyword(s):  
Biological Treatment ◽  
High Strength ◽  
Anaerobic Treatment ◽  
Cod Removal ◽  
Anaerobic Sludge ◽  
Aerobic Treatment ◽  
Rotating Biological Contactor ◽  
Anaerobic Process ◽  
Fixed Film ◽  
Removal Efficiencies

Biological treatment of a high strength chesses whey wastewater was investigated in a series of aerobic-anaerobic experiments. Aerobic treatment of the wastewater was conducted in a three-stage rotating biological contactor (NRBC), while the anaerobic process was performed in an up-flow anaerobic sludge fixed film (UASFF) bioreactor. Various concentrations of wastewater with influent COD of 40,000 to 70,000 mg/L were introduced in to NRBC system. Treatability of the samples at various HRTs of 8, 12 and 16 h was evaluated in the NRBC reactor. The effluent streams of the NRBC system were introduced into UASFF bioreactor. Anaerobic treatment of the pretreated samples was investigated in an UASFF with the same HRTs of 8, 12 and 16 h. The obtained results revealed that more than 53, 69 and 78% of the influent COD (50,000 mg/L) were removed in NRBC reactor at HRTs of 8, 12 and 16 h, respectively. Maximum COD removal efficiencies of 96, 96.8, 97.4 and 96.4% were achieved in the combined systems at total HRT of 32 h for influent COD of 40,000, 50,000, 60,000 and 70,000 mg/L, respectively.

CHEMICAL PULPING. Oxidative degradation of AOX in softwood-based kraft mill effluents from E C F bleachin g

2012 ◽  
Vol 27 (4) ◽  
pp. 707-713 ◽  
Author(s):  
Jukka Pekka lsoaho ◽  
Suvi Tarkkanen ◽  
Raimo Alen ◽  
Juha Fiskari
Keyword(s):  
Reaction Time ◽  
Oxidative Degradation ◽  
Cost Effective ◽  
Process Conditions ◽  
Main Process ◽  
Chemical Pulping ◽  
Kraft Mill ◽  
Organic Halogens ◽  
Aox Removal ◽  
Adsorbable Organic Halogens

Abstract Softwood-based kraft mill bleaching effluents from the initial bleaching stages D0 and E1 (the bleaching sequence being D0E 1D 1 E2D2) were treated by the oxidative Fenton method (H20rFeS04) to decompose organic pollutants contammg adsorbable organic halogens (AOX). Experiments designed using the Taguchi method were applied to predict the process conditions that would result in a cost-effective and adequate removal of AOX. In addition to the composition and concentration of the reagents (H202 and Fe2+), the main process parameters selected were temperature and reaction time, while pH was adj usted to an approximate value of 4 (the volumetric ratio of the mixed effluents D0:E 1 was 3 :2). The results indicated that an AOX removal of about 70% for this mixture ( corresponding to about 50% for the mill) was achieved when the eftluent samples were treated for 60 min at 70°C with H202 and Fe2+ at a concentration of 1 600 mg/1 and 28 mg/1, respectively.

Sign in / Sign up

Export Citation Format

Share Document