Biological Treatment Of Effluents Research Articles

EVALUATION OF UV/O3 AND UV/H2O2 PROCESSES FOR NONBIODEGRADABLE COMPOUNDS: IMPLICATIONS FOR INTEGRATION WITH BIOLOGICAL PROCESSES FOR EFFLUENT TREATMENT

Poorly biodegradable compounds reduce the efficiency of biological effluent treatment processes. These are often encountered in pharmaceutical and speciality chemical industries. Advanced oxidation technologies (AOT) are appropriate for the conversion of such compounds into biodegradable entities. Tetrahydrofuran, 1,4-dioxane, and pyridine are heterocyclic compounds that are known to be recalcitrant and nonbiodegradable. AOT were investigated for the destruction of these model compounds. Two forms of AOT, UV-O3 and UV-H2O2, were studied. UV-H2O2 treatment resulted in higher biodegradability for tetrahydrofuran; UV-O3 treatment resulted in higher biodegradability for 1,4-dioxane. For pyridine, neither treatment improved biodegradability. For efficient integration of AOT with biological processes for effluent treatment, it is necessary to evaluate the AOT with multiple objectives, such as level of destruction of target compound, level of reduction in COD, and enhancement of biodegradability. Due to the presence of multiple pollutants in real effluents and in AOT, kinetics of oxidation elucidated with single compounds is unlikely to be useful.

Effect of ozonation on chemical oxygen demand fractionation and color profile of textile wastewaters

AbstractFiltration and ultrafiltration with a size range of 2–1600 nm were used to evaluate the effect of ozonation on the particle size distribution‐based chemical oxygen demand (COD) and color profiles of textile wastewater before and after biological treatment. Ozonation induced a net effect of 9% COD reduction in the influent and 15% in the effluent. However, a more in‐depth evaluation based on particle size distribution and mass balance for the influent revealed different mechanisms of ozonation, which were interpreted as total oxidation in the soluble range, replenishment of soluble COD through solubilization of organics into simpler compounds and polymerization towards the upper size range (>220 nm). For the biological treatment effluent, the greatest effect of ozonation was in the lower particle size range (<8 nm). Ozone was very effective for color removal, giving 80–93% optical density reductions in the influent and 96–99% in the effluent, depending on the excitation wavelength selected. Ozonation of the influent removed practically all color fractions, except in the particulate range. In the effluent, the particulate fraction was removed by biological treatment and settling and consequently the remaining color were almost entirely removed by ozonation. Copyright © 2005 Society of Chemical Industry

염색폐수의 생물학적 전처리 조건변화에 의한 최적 펜톤시약 투입량 결정에 관한 연구

The consecutive combination process of a biological process as the pre-treatment and a chemical process as the post-treatment is applied for the dyeing wastewater. The poor efficiency of biological treatment using pure oxygen makes the chemical treatment cost high. It is necessary to improve the efficiency of biological treatment in order to reduce the cost of chemical treatment. The purpose of this paper is to find the minimum dose of chemical reagent to fit the Discharged Water Quality Standards for the different biological treatment effluents. Results revealed that the minimum dosage of Fenton's reagent lead to save the cost of chemical treatment based on the guideline dose in the treatment plant. The possible maximum saving reagents was up to <TEX>$70\%$</TEX> for the effluent of the pilot plant packed with the carrier imbedded microorganisms which were selected from the present treatment plant.

A novel approach for extraction of PCR-compatible DNA from activated sludge samples collected from different biological effluent treatment plants

This paper describes a method that facilitates the extraction of PCR-compatible DNA from different activated sludge samples. The approach involves a novel preprocessing step in DNA extraction, which removes potential PCR inhibitors. The sludge was washed with different ratios of acetone and petroleum ether after pretreatment with 0.01% Tween-20 at 50 °C. It was observed that an initial washing step with 50 mM Tris–HCl, pH 9.0, before the detergent–solvent step, improved the quality of the extracted DNA. The extraction protocol resulted in amplifiable amounts of DNA when 10 mg of a sludge sample was used, even in the presence of phenol as a sludge contaminant. The usefulness of the extracted template was demonstrated by carrying out different PCR reactions. The random amplified polymorphic DNA (RAPD) patterns demonstrated the diversity of sludge samples.

Effect of chemical treatment on soluble residual COD in textile wastewaters

The effect of chemical treatment on the magnitude of soluble residual COD in the biological treatment effluent is investigated for knit fabric finishing wastewater. Bentonite is selected for its potential to remove soluble COD together with color and particulate components. Chemical treatment using bentonite, when applied prior to biological treatment removes around 40% of the biodegradable as well as soluble inert COD initially present in the wastewater. As a chemical post-treatment, it acts as a polishing step, removing particulate matter and a minor portion of around 20% of the remaining soluble COD. These findings suggest chemical pre-treatment as a better alternative for the optimization of soluble COD removal.

Biological treatment of effluent containing textile dyes

Colour removal of textile dyes from effluent was evaluated using a laboratory ‘upflow anaerobic sludge blanket’ reactor. Several commercial dyes were selected to study the effect of dye structure on colour removal. The anaerobic reactor was fed with glucose, an easily biodegradable organic matter and selected individual dyes. Results show that some of the dyes are readily reduced under anaerobic conditions even at a high concentration of 700 mg/l. The average removal efficiency for acid dyes using this method was between 80 and 90% and that observed for the direct dye used was 81%. Laboratory experiments using the anaerobic reactor with disperse dyes, such as an anthraquinonebased dye, were unsuccessful even at low concentrations of 35 mg/l. Additional experiments were conducted to evaluate the toxicity of a selected disperse dye to an anaerobic environment. Results indicate that the purified dye is more toxic to the biomass than the commercial one.

Azo-dye degradation in an anaerobic-aerobic treatment system operating on simulated textile effluent.

Decolorisation of azo dyes during biological effluent treatment can involve both adsorption to cell biomass and degradation by azo-bond reduction during anaerobic digestion. Degradation is expected to form aromatic amines, which may be toxic and recalcitrant to anaerobic treatment but degradable aerobically. Methods for the quantitative detection of substituted aromatic amines arising from azo-dye cleavage are complex. A simple qualitative method is suggested as a way in which to investigate whether decolorisation is actually due to degradation, and whether the amines generated are successfully removed by aerobic treatment. Samples from a combined anaerobic-aerobic system used for treating a simulated textile wastewater containing the reactive azo dye Procion Red H-E7B were analysed by high-performance liquid chromatography/ultraviolet (HPLC-UV) methods. Anaerobic treatment gave significant decolorisation, and respiration-inhibition tests showed that the anaerobic effluent had an increased toxicity, suggesting azo-dye degradation. The HPLC method showed that more polar, UV-absorbing compounds had been generated. Aerobically, these compounds were removed or converted to highly polar compounds, as shown by HPLC analysis. Since the total organic nitrogen (TON) decreased aerobically as organic N-containing compounds were mineralised, aromatic amine degradation is suggested. Although only a simple qualitative HPLC method was used, colour removal, toxicity and TON removal all support its usefulness in analysing biotreatment of azo dyes.

Extraction of intact ribosomal RNA from anaerobic bioreactor samples for molecular ecological studies.

BioTechniquesVol. 27, No. 6 BenchmarksOpen AccessExtraction of Intact Ribosomal RNA from Anaerobic Bioreactor Samples for Molecular Ecological StudiesAshraf Ibrahim & Birgitte K. AhringAshraf IbrahimThe Technical University of Denmark, Lyngby, DenmarkSearch for more papers by this author & Birgitte K. Ahring*Address correspondence to Prof. Birgitte K. Ahring, Department of Biotechnology-BLD 227, The Technical University of Denmark, 2800 Lyngby, Denmark. Internet: E-mail Address: bka@ibt.dtu.dkThe Technical University of Denmark, Lyngby, DenmarkSearch for more papers by this authorPublished Online:22 Aug 2018https://doi.org/10.2144/99276bm10AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinkedInRedditEmail FiguresReferencesRelatedDetailsCited ByImproved rRNA extraction from biofouling and bioreactor samplesInternational Biodeterioration & Biodegradation, Vol. 174Rapid extraction of total RNA from an anaerobic sludge biocoenosis30 August 2013 | Folia Microbiologica, Vol. 59, No. 2Evaluation of molecular methods used for establishing the interactions and functions of microorganisms in anaerobic bioreactorsWater Research, Vol. 42, No. 3Optimization of RNA isolation from the archaebacterium Methanosarcina barkeri and validation for oligonucleotide microarray analysisJournal of Microbiological Methods, Vol. 67, No. 1Microbial population dynamics at effluent treatment plantsJournal of Environmental Monitoring, Vol. 7, No. 6A novel approach for extraction of PCR-compatible DNA from activated sludge samples collected from different biological effluent treatment plantsJournal of Microbiological Methods, Vol. 52, No. 3Molecular Ecology of Anaerobic Reactor Systems18 March 2003Effect of temperature increase from 55 to 65°C on performance and microbial population dynamics of an anaerobic reactor treating cattle manureWater Research, Vol. 35, No. 10 Vol. 27, No. 6 Follow us on social media for the latest updates Metrics Downloaded 121 times History Published online 22 August 2018 Published in print December 1999 Information© 2018 Author(s)PDF download

The Diffusion of Biological Waste-Water Treatment Plants in the Dutch Food and Beverage Industry

This article develops an economic model of environmental technology adoption decisions. The model is applied econometrically to the diffusion of biological waste-water treatment plants in the Dutch food and beverage industry. It shows that it is possible to explain the overall diffusion pattern of biological waste-water treatment plants in terms of a rational choice model in which prospective adopters trade off the costs of effluent treatment against the savings on effluent tax payments. Effluent charges are shown to be a significant positive factor in the timing of adoption of biological effluent treatment plants. This result is brought out by both the rational choice and the epidemic models. None of the models however can explain year-to-year changes in the ownership of biological waste-water treatment plants during the 1974–91 period, which suggests that there are other factors, not included in the model, that affect the timing of adoption.

The use of ozone to decolorize residual direct paper dyes in kraft paper machine whitewater

Production of colored kraft papers results in strongly colored paper machine spent Whitewaters (ww). The residual dyes prevent efficient recycle of the ww and necessitate periodic system cleanings. Many of the dyes are not adsorbed or degraded by biological effluent treatment and therefore discolor receiving waters. Ozone was tested as a bleaching agent for 15 direct paper dyes added at typical residual levels to kraft mill ww. These dyes included azo, polyazo, stilbene, benzothiazole and phthalocyanine direct dyes commonly used in Canadian dyed paper production. Ozone charges of 15 ‐100 mg/L rapidly bleached most of the dyes, although a few of the yellow stilbene and azo dyes were quite resistant. The efficiency of ozone‐mediated residual dye bleaching was altered substantially by the pH, the ww concentration, and the target dye's chemical structure. Preozonation of residual dye‐containing ww greatly decreased the color conferred to bleached kraft pulp fibers added to the ww. Thus, ozonation should permit much more ww recycle (less effluent) when changing colors on the paper machine. Depending on the availability of oxygen or ozone in a mill, and local ozone economics, ozone may be the most efficient, cost‐effective way to improve ww quality, increase ww recycle and minimize effluent color problems and environmental impact.

5418166 Process and device for the biological treatment of effluents from wine cellars : Ehlinger Frederic Le Peco, France Assigned to Societe Degremont

5418166 Process and device for the biological treatment of effluents from wine cellars : Ehlinger Frederic Le Peco, France Assigned to Societe Degremont

5418166 Process and device for the biological treatment of effluents from wine cellars : Ehlinger Frederic Le Peco, France Assigned to Societe Degremont

5418166 Process and device for the biological treatment of effluents from wine cellars : Ehlinger Frederic Le Peco, France Assigned to Societe Degremont

ＮＨ３‐Ｎの硝化によるＢＯＤ５値への影響

BOD5 is an index used for evaluation of water environment and purification function of wastewater treatment facilities. This value indicates bio-chemical oxygen demand consuming by organic matter. However, the BOD5 measurement is affected by oxygen demand of nitrification and BOD5 sometimes indicates an abnormal higher value compared with COD(Mn).By examining the trend of DO, NOx-N in incubation bottles and analyzing the change of effluent water quality in wastewater treatment facilities, we obtained some results shown bellow.1. The nitrification in incubation bottle occurred in initial 2 days for cultivation period of 5 days and observed exponential increase of nitrate.2. The BOD5 values of effuents from wastewater treatment facilities often observed larger than the COD(Mn) value and sometimes take 3 times higher than COD(Mn) value.3. The reaction rate of nitrification in incubation bottle was affected by NH3-N concentration. At the higher concentration of NH3-N in BOD5 measurement sample, the rate was in inverse proportion to NH3-N concentration. At the lower NH3-N concentration, however, it was in direct proportion to NH3-N concentration.In case of being affected by nitrification in BOD5 measurement, it is difficult to evaluate effluent water quality and purification function of wastewater treatment facilities by effluent BOD5. So it is necessary to measure the values of ATU-BOD, NH3-N, NO2-N, NO3-N with BOD5 measurement for biological treatment effluents.

Influence of nutrient concentration in new operating criteria for biological removal of phosphorus from wastewaters

The actual practicability of biological treatment of effluents heavily polluted by phosphoric compounds is evaluated in this paper. Preliminary batch tests have shown that high COD levels inhibit phosphorus release during anaerobic conditions but allow, at the same time, a more efficacious removal during the subsequent aerobic stage. Removal yields exceeding 60% have been calculated for an influent COD level of about 840 mg/l. The A/O process, suitably modified so as to alternate aerobic and anaerobic phases in the same reactor, has been tested for the biological removal of phosphorus in synthetic wastewaters with high phosphate concentrations. The start-up phase, carried out with a synthetic solution having a starting phosphorus concentration of 10 mg/l, showed average phosphate and COD removals of 78 and 90%, respectively. The results obtained after reaching steady-state conditions, by feeding P concentrations up to 100 mg/l, seem to indicate this process as an excellent means of reducing phosphorus emissions into the environment and therefore may contribute to the solution of eutrophication-related problems. Removals higher than 90% have been assured for wastewaters containing phosphate levels up to 70 mg/l; at higher concentrations, the system proved capable of tolerating phosphate overloading for no more than 10 days; yield then rapidly fell to zero.

Instrumentation control and automation in the control of biological effluent treatment

The role of instrumentation, control, and automation (ICA) in the management, operation, and control of domestic and industrial wastewater treatment works is examined following an historical account of developments in the UK over the past two decades. Included also are aspects of process optimization and process selection, taking into account size and types of works and populations served. The particular ICA requirements of individual unit processes are examined and the effects of unattended operation and remote supervision are considered. Particular attention is paid to measurement technology, the shortcomings of available instruments and systems, and recent developments of relevance, with particular emphasis being placed on microelectronic and fibre- and electro-optic-based sensors and on the role of advanced commenting methods including expert systems. Progress with biologically based sensors is also discussed.

Biological treatment of effluents from a coal tar refinery using immobilized biomass

AbstractAn airlift‐loop reactor with a fluidized bed was used for the microbiological removal of a complex mixture of aromatic substances originating from coal tar process waters. A specially adapted mixed microbial culture derived from several soil and sludge samples was immobilized on fluidized sand particles and retained in a reactor at high biomas concentrations of 3 to 16 g dry matter per liter, depending on the COD‐load. In a two‐stage pilot plant, those aromatic substances which passed through the first stage either unaltered or only partially oxidized were effectively eliminated by the immobilized biomass in the second stage. Whereas most of the waste water components such as phenols and quinoline were already degraded by a conventional activated sludge system in the first stage, the majority of nitrogen‐containing aromatic bases could be sufficiently eliminated with specially adapted micro‐organisms in the second stage. Although the COD‐feed load was increased to 12 and 15 kg m−3 d−1 in the first and second stages, respectively, it was removed to the extent of 87% on the average with an overall residence time varying between 11.5 and 29 h.

Sequential degradation of chlorophenols by photolytic and microbial treatment

Using the radiolabeled model pollutants 2,4-dichlorophenol (DCP) and 2,4,5-trichlorophenol (TCP) the authors demonstrated that the brief UV (300-nm) photolysis greatly facilitates the removal of the two chlorophenols from sewage through accelerated mineralization and binding of polar products. The addition of 0.1 M H/sub 2/O/sub 2/ strongly accelerated the photolysis process resulting in the half-lives of 1.68 and 0.87 min for DCP and TCP, respectively. In natural sunlight, half-lives of the chlorophenols were less than 1 day when H/sub 2/O/sub 2/ was present. During 4 days of incubation in activated sewage sludge, only 3% of unphotolyzed DCP and 1% of unphotolyzed TCP were mineralized. Mineralization rose to 79 and 59%, respectively, after photolysis in the presence of H/sub 2/O/sub 2/. Photolysis without H/sub 2/O/sub 2/ resulted in removal of chlorophenols from solution chiefly by binding. Increased mineralization and binding were observed also upon incubation of photolyzed chlorophenols in soil. Disruption of carbon-halogen bonds by brief photolysis followed by traditional biological effluent treatment offers an alternative to activated charcoal treatment for removal of xenobiotics from industrial effluents.

The recovery of platinum metals by the water hyacinth

Abstract Model experiments on the recovery of platinum metals from solution by water plants have been carried out, in particular using the free floating water hyacinth. It has been demonstrated that this plant removes platinum metals from nutrient solution. Preliminary experiments using a treated trade effluent demonstrated that plant species were able to remove the traces of platinum metals remaining in solution in the effluent. The possibility of the large scale use of such processes is discussed. The water hyacinth is a likely candidate for the biological treatment of effluent, and the background to its use is reviewed briefly.

Research and development of membrane technologies and their applications in Japan

Several projects concerning membrane developments and applications supported by various Japanese Ministries will be explained. Interesting membranes, which have been developed in these projects are pervaporation membranes for alcohol separation, gas separation membranes for hydrogen separation and ultrafiltration membranes for high temperature sterilization. Membranes applied to various biotechonologies are also explained. One example is in the alcohol fermentation process, where UF is used for recovery of enzymes, RO for concentration of sugar and pervaporation process for recovery of alcohol from fermentation broth. The other example is in the biological effluent treatment process, where UF membranes will be used instead of sedimentation. Other interesting applications of UF, and new membranes made of porous ceramics and glass will be explained. Finally recent results of our works, including natures of dynamically formed membranes, those of charged ultrafiltration membranes and membrane distillation process, will be reported.

Phosphorus removal by activated alumina

Activated alumina effectively removed orthophosphates from effluent of biological sewage treatment plant and from synthetic aqueous solutions in continuous flow and batch systems. Acidic and basic treatment of the activated alumina significantly improved the sorption capacity for phosphorus removal. The sorption capacity of an activated alumina columnar packed bed was found to be 30 mg PO 4 −3 per gram alumina, up to the breakthrough of 1000 bed volumes. Langmuir adsorption isotherms from biological treatment effluent showed that Alcoa F-1 acidic and basic activated alumina have a very high orthophosphate adsorption capacity of 179 meq PO 4 −3/100 g alumina. The mechanism of orthophosphate removal on activated alumina is mainly ion exchange accompanied by chemical reactions, precipitation and formation of complexes.