Biological Treatment Facilities Research Articles

SIMPLE METHOD OF DETECTION AND INTENSIVITY ESTIMATION OF ANAEROBIC PROCESSES ACCOMPANIED BY GAS RELEASE

The method of detection and intensivity estimation of anaerobic processes accompanied by formation of gases (CO2, CH4, H2, N2 etc.) is proposed. This method is realized in such a way: the PET-bottle is filled by 4/5 of its volume with the nutrients solution or wastewater, anaerobic bacteria, activated sludge or other anaerobic biocenoses. Thereafter by simply squeezing of a PET-bottle the air is removed from it and the bottle is tightly corked. The bottle is then placed into a thermostat and the levels of gas generated and accumulated in this anaerobic bioreactor are periodically measured. whenever necessary gas composition and concentration change of substances in the water (medium) are analyzed. Thanks to the method for the first time in Ukraine there has been identified the presence of ANAMMOx (Anaerobic Ammonium Oxidation) bacteria in activated sludge of biological treatment facilities. By this method the possibility of anaerobic treatment of beer-brewing wastewater with increased concentration of chloride-ion (up 2500 mg/l) was proved.

Analysis and retrofit design of biological wastewater treatment facilities using process simulation tools

Analysis and retrofit design of biological wastewater treatment facilities using process simulation tools

Tracking Airborne Legionella and Legionella pneumophila at a Biological Treatment Plant

Biological treatment plants are frequently used to degrade organic substances in wastewater from wood refinement processes. Aeration ponds in such plants provide an optimal growth environment for many microorganisms, including Legionella species. To investigate whether legionellae could be dispersed as aerosols from the ponds and transported by the wind, the wetted-wall cyclone SASS 2000(PLUS) and the impactors MAS-100 and STA-204 were used to collect air samples directly above, upwind, and downwind of aeration ponds during a 4-month period. Computational fluid dynamics was used a priori to estimate the aerosol paths and to determine suitable air-sampling locations. Several Legionella species, including Legionella pneumophila, were identified in air samples at the biological treatment plant using microbiological and molecular methods. L. pneumophila was identified up to distances of 200 m downwind from the ponds, but, in general, not upwind nor outside the predicted aerosol paths. The highest concentration level of viable legionellae was identified directly above the aeration ponds (3300 CFU/m3). This level decreased as the distance from the aeration ponds increased. Molecular typing indicated that a single clone of L. pneumophila was dispersed from the ponds during the period of the study. Thus, our study demonstrated that aerosols generated at aeration ponds of biological treatment facilities may contain L. pneumophila, which then can be transported by the wind to the surroundings. The methods used in this study may be generically applied to trace biological aerosols that may pose a challenge to environmental occupational health.

Newtown Creek Demonstration Project Wet Weather Operating Strategies

Newtown Creek Demonstration Project Wet Weather Operating StrategiesIn 2004, the Newtown Creek Wastewater Treatment Plant (WWTP), designed for 13.6 m3/sec average daily flow (ADF) was operating under an interim permit with new secondary treatment permit limits scheduled to go into effect in January 2008. The facility is currently undergoing a plant-wide upgrade that includes increasing the biological treatment facilities by 50% (from two to three treatment...Author(s)John FortinPaul PittPatrick O'ConnorFrank GiardinaJoseph HusbandCarl KochSourceWater PracticeSubjectArticlesDocument typeConference PaperPublisherWater Environment FederationPrint publication date Jun, 2008ISSN1933-1770SICI1933-1770(20080628)2:4L.1;1-DOI10.2175/193317708X335190Volume / Issue2 / 4Content sourceWater PracticeFirst / last page(s)1 - 17Copyright2008Word count81Subject keywordsWET WEATHERSTEP FEED GATE ADDITIONFINAL SETTLING TANKHYDRAULIC LOADINGSOLIDS LOADING

The use of Magallanic peat as non-conventional sorbent for EDTA removal from wastewater

Kraft mills are responsible for large volumes discharges of highly polluted effluents. Application of new bleaching processes (i.e. total chlorine-free (TCF) process) is already a feasible option to reduce environmental impacts. The current trend in the increase in the production of TCF pulp will proportionally increase the consumption of chelating agents. The most commonly used chelants, ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DPTA) are supposed to be relatively persistent substances, poorly degradable in biological treatment facilities and are subsequently considered as environmentally critical compounds. Adsorption could be used as a treatment technique to remove recalcitrant compounds from wastewaters. However, in most cases, sorbent and regeneration costs can make the whole process not economically feasible. The goal of this study was to evaluate the use of Magallanic peat as non-conventional sorbent for EDTA removal from wastewater. Adsorption studies were carried out considering a 2 3 factorial design. pH, temperature and sorbent/sorbate (S/S) relationship effects were evaluated in EDTA adsorption onto Magallanic peat. In addition, adsorption isotherm constants were determined according to the Langmuir and Freundlich models. The results showed that the optimal conditions for EDTA adsorption onto Magallanic peat were 20 °C, acid pH (4.0) and a low sorbent/sorbate ratio (0.1/100). At these conditions Magallanic peat showed an adsorption capacity for EDTA (Cs sat) of 128.2 mg/g, comparable and even better than activated carbon (Cs sat 56.5 mg/g). EDTA adsorption data at 60 °C obtained are not shown due to Magallanic peat degradation phenomena.

Newtown Creek Demonstration Project Wet Weather Operating Strategies

Newtown Creek Demonstration Project Wet Weather Operating StrategiesIn 2004, the Newtown Creek Wastewater Treatment plant, designed for 310 mgd average daily flow (ADF) was operating under an interim permit with new secondary treatment permit limits scheduled to go into effect in January 2008. The facility is currently undergoing a plant-wide upgrade that includes increasing the biological treatment facilities by 50% (from two to three batteries) and changing the...Author(s)John FortinPaul PittPatrick O'ConnorFrank GiardinaJoseph HusbandCarl KochSourceProceedings of the Water Environment FederationSubjectSession 10: I Can See Clearly Now: Clarifier Operation IlluminatedDocument typeConference PaperPublisherWater Environment FederationPrint publication date Oct, 2007ISSN1938-6478SICI1938-6478(20071001)2007:19L.831;1-DOI10.2175/193864707786831309Volume / Issue2007 / 19Content sourceWEFTECFirst / last page(s)831 - 849Copyright2007Word count79Subject keywordsWET WEATHERSTEP FEED GATE ADDITIONFINAL SETTLING TANKHYDRAULIC LOADINGSOLIDS LOADING

Analysis and retrofit design of biological wastewater treatment facilities using process simulation tools

Analysis and retrofit design of biological wastewater treatment facilities using process simulation tools

Eubacterial diversity of activated biomass from a common effluent treatment plant

A common effluent treatment plant (CETP) is a biological wastewater treatment facility that receives wastewater from different industries. The activated biomass in the CETP survives on a wide range of chemicals with no fixed wastewater characteristics. We carried out a diversity analysis of this activated biomass using culture as well as culture-independent techniques. Using culture-based techniques, strains belonging to 26 different genera from the phyla Proteobacteria, Actinobacteria and Firmicutes were isolated. The gamma-proteobacteria was the best represented class, with 36.5% of the isolates. Bacterial diversity was also analyzed culture-independently by means of sequence determination of cloned 16S rRNA genes. Twenty-one different genera from the phyla Proteobacteria, Firmicutes, Planctomycetes and Bacteroidetes were identified. The total diversity of the activated biomass was composed of members of five known phyla, represented by 37 genera, with the Proteobacteria constituting the most abundant phylum detected. However, a very large fraction of the diversity represented a hitherto unidentified bacterial population. More than half (50.2%) of the 16S rDNA clones represented unidentified non-culturable bacteria, underlining the vast untapped diversity of CETP communities. Our results also indicate that both culture-based and culture-independent techniques should be combined to cover the microbial diversity of complex ecosystems.

Assessment by Microscopy of the Coverage of Sludge Flocs by a Nano‐scale Surface Layer

AbstractFlocs are irregularly shaped suspended particles of complex structure and composition that occur naturally in aquatic systems. In water treatment facilities, the settling of flocs is extremely important. Transmission electron microscopy was used to quantify the formation of a nano‐scale surface layer on flocs from two laboratory bioreactors modelling a biological wastewater treatment facility. By comparing different floc populations, we demonstrated that flocs that settled quickly out of wastewater had a significant amount of this layer, whereas those with little nano‐scale surface layer had poor settling properties. This morphological feature of floc ultrastructure may permit engineering manipulations that promote floc settling.

Electron beam treatment of textile dyeing wastewater: operation of pilot plant and industrial plant construction

A pilot plant for treating 1000 m3/day of dyeing wastewater with e-beam has been constructed and operated since 1998 in Daegu, Korea together with the biological treatment facility. The wastewater from various stages of the existing purification process has been treated with an electron beam in this plant, and it gave rise to elaborating the optimal technology of the electron beam treatment of wastewater with increased reliability for instant changes in the composition of wastewater. Installation of the e-beam pilot plant resulted in decolorizing and destructive oxidation of organic impurities in wastewater, appreciable reduction of chemical reagent consumption, in reduction of the treatment time, and in increase in the flow rate limit of existing facilities by 30-40%. Industrial plant for treating 10,000 m3/day each, based upon the pilot experimental result, is under construction and will be finished by 2005. This project is supported by the International Atomic Energy Agency (IAEA) and Korean Government.

Impact of activated sludge‐derived colloidal organic carbon on behavior of estrogenic agonist recombinant yeast bioassay

The impact of size-fractionated colloidal organic carbon (COC) originating from a biological wastewater treatment facility on the sensitivity of the yeast estrogen screen (YES) bioassay containing the human estrogen receptor (hER) gene was evaluated. Dose-response curves of serially diluted 17beta-estradiol (E2), both in the presence and absence of COC, were generated by the YES bioassay. The concentration of E2 leading to a 50% YES response (effective concentration 50%, or EC50) was used to evaluate quantitatively the estrogenic activity of the different COC-E2 mixtures. The EC50 values for all COC size fractions, including COC-free samples (<1 kD), were statistically greater than the controls using Milli-Q water. Normalized EC50 values significantly increased as a function of COC concentration for the larger size fractions (>0.22 microm), but were not significantly affected by smaller COC material at environmental levels (1-5 mg/L), while both colloidal polysaccharide concentrations and colloidal fluorophores (measured at an excitation/emission wavelength pair of 350 nm/450 nm) appear to have an important role in the sensitivity of the YES bioassay. Estimates of the colloid-associated E2 fraction did not predict accurately increases in EC50 values. Matrix effects of the specific environment being tested with the YES bioassay need to be evaluated closely due to the sensitivity of the hER and reporter plasmid.

Raising and Controlling Study of Dissolved Oxygen Concentration in Closed-type Aeration Tank

This study investigated the promotion and control of dissolved oxygen (DO) concentration of the closed-type aeration tank via practical experiments in the wastewater treatment system of a 5-star hotel in Taipei. As with limited and treasured space in Taiwan, before the completion of the sewer system construction in cities, to utilize the mat foundation under large buildings as the space of sewage treatment plant still has been one of the alternatives of those sewage treatments. However, aeration tanks constructed in the mat foundation of buildings have smaller effective water depth, which will cause a lower total transfer amount of DO. Controlling the total exhaust gas flow rate can increase the pressure on such closed-type aeration tanks. The DO concentration thus may increase according to Henry's Law. Furthermore, it may enable operators to adjust the DO concentration of the aeration tank more precisely and thus sustain optimal operating conditions in these treatment facilities. Practical experiments indicated that the DO concentration of aeration tank maintains an average of 3.8 mg l-1, obtaining the optimum operating conditions. The efficiency of the biological treatment facilities in the mat foundation could be markedly improved.

Investigation of Sorption Behavior between Pyrene and Colloidal Organic Carbon from Activated Sludge Processes

The sorption behavior of pyrene for different size fractions of colloidal organic carbon (COC) originating from two biological wastewater treatment facilities (a full-scale activated sludge system (FSAS) and a membrane bioreactor (MBR)) was investigated by fluorescence quenching. Fluorescence lifetime measurements demonstrated a dynamic quenching component in all samples, including the colloidal-free filtrates. COC sorption coefficients (Kcoc) for pyrene ranged from <1 x 10(3) L/kgcoc to 80 x 10(3) L/kgcoc and were comparable to values obtained in the literature for natural organic matter. Both linear and nonlinear behaviors were observed in the Freundlich-described converted isotherms (n = 0.89-2.1). The aromatic content of COC was quantified by the molar extinction coefficient at 280 nm (e280). Good correlations were observed between COC-pyrene sorption coefficients and e280 coefficients, suggesting that e280 may be a useful tool for predicting colloidal transport of hydrophobic organic compounds (HOCs) from activated sludge systems. The removal of COC from treated effluents may appreciably reduce the concentrations of HOCs discharged to receiving streams.

Sorption of 17beta-estradiol and 17alpha-ethinylestradiol by colloidal organic carbon derived from biological wastewater treatment systems.

Sorption coefficients (K(COC)) between 17beta-estradiol (E2), 17alpha-ethinylestradiol (EE2) and size-fractionated colloidal organic carbon (COC) derived from two biological wastewater treatment facilities were quantified by fluorescence quenching. The two wastewater treatment systems included a full-scale activated sludge system (FSAS) and a membrane bioreactor (MBR). The K(COC) coefficients were highly variable and ranged between (<1 to 179) x 10(3) L/kgCOC for E2 and (<1 to 430) x 10(3) L/kgCOC for EE2 and were higher than expected from the analytes octanol-water partition coefficient. Correlations between the molar extinction coefficients measured at 280 nm (e280) and K(COC) coefficients were weak but stronger for E2 compared to EE2. Attempts at correlating sorption behavior with colloidal protein and polysaccharide concentrations were only marginally successful (r2 approximately 0.4). These low correlations suggest that aromatic content, protein, or polysaccharide concentration can not adequately explain E2 and EE2 sorption behavior to COC and that other fractions of the organic matter pool play an important role in binding. A substantial portion of the aqueous E2 and EE2 concentrations (up to 60%) may be associated with colloidal material, suggesting that COC may play a role in the fate and transport of E2 and EE2 during the activated sludge process.

Modeling and Evaluation of Biological Wastewater Treatment Facilities - What Role can Process Simulators Play?

The role of process simulation in designing, evaluating, and optimizing wastewater treatment facilities is discussed. Alternatives for controlling VOC emissions from treatment plants and removing dissolved solids from clarified effluent streams are evaluated

Degradation potential of musty odour in a drinking water source by a biofilm method

The purpose of this study was to evaluate the degradation potential of 2-methylisoborneol (MIB) and its producer by a biofilm process. The cyanobacteria Phormidium tenue was isolated from the biofilm in a biological treatment facility for water supply. MIB was efficiently removed by the facility and the removal ratio was about 70% during the investigation period of 2 years. There was a favourable correlation between the removal rate of P. tenue and the number of micro-organisms, especially ciliates on the biofilm. But a high rise of pH value due to sudden proliferation of cyanobacteria induced a reduction in removal of P. tenue and MIB. It was found that the ciliate protozoa and pH value were very important factors for the removal of MIB and P. tenue .

Biodegradation of microcystis and microcystins by indigenous nanoflagellates on biofilm in a practical treatment facility

The potential for degradation of Microcystis and microcystins by organisms in biofilm in a practical biological treatment facility combined with conventional treatment processes was examined. Viable cells of Microcystis viridis, which produced microcystin LR, RR and YR, were degraded in 6 to 10 days by the addition of biofilm collected in early summer, midsummer and autumn. Monas sp. grew remarkably well compared with other organisms in the samples of all seasons. Therefore, we conclude that Monas sp. was indigenous animals in the biological treatment facility and was able to degrade Microcystis cells. Some previous studies reported the predation of Microcystis cells by Monas guttula in pure culture conditions (monoxenic culture). We clarified that Monas sp. can grow and prey on Microcystis cells even in mixed culture including many kinds of other organisms in biofilm in a practical treatment facility. Also, intracellular microcystin LR, RR and YR in Microcystis cells could be degraded simultaneously with high reduction of Microcystis cells by organisms in biofilm.

Degradation of microcystin by biofilm in practical treatment facility

Potential for degradation of microcystin by biofilm was examined by some batch experiments using biofilm scraped from practical biological treatment facility combined with conventional treatment processes. The viable cells of Microcystis viridis, which produced microcystin LR, RR and YR were degraded at 6 to 10 days by the addition of biofilm. Biofilm collected in summer season had especially higher potential for degradation of Microcystis with complete degradation at 6 days. In all seasons, Monas spp. grew remarkably, accompanied with the higher decrease of the viable cells of Microcystis and the micro-animals were considered as a main predator for Microcystis cells. Intracellular microcystin LR, RR, YR were degraded simultaneously with high reduction of Microcystis cells. Dissolved microcystin LR of 1,000 microg l(-1) was effectively degraded by indigenous aquatic bacteria on biofilm during 5 days, the degradability became higher with the increase in the concentration of microcystin LR. From the results of our research, it was clarified that the aggregated microorganisms consisting of biofilm had high potential for degradation of intracellular and dissolved microcystin.

A Steady-State Model for the Design of Biological Wastewater Treatment Facilities

A steady-state model for carbon oxidation and nitrogen removal suitable for the design of wastewater and sludge suspended growth and wastewater attached growth biological processes is proposed. The model is based on the WEF-ASCE model for combined BOD5 and nitrogen oxidation activated sludge processes. Kinetic and stoichiometric coefficients have been calibrated from data of municipal wastewater treatment plants. Results of model evaluation are presented through four case studies involving full-scale wastewater treatment plants. The case studies have been selected to show the model applicability to different scenarios: from simple small plant to complex large plant or from domestic influent wastewater to major industrial contributions.

Role of Microorganisms in Biofilm on Degradation of Musty Odor Producing Phormidium tenue.

In this study, potential of biodegradation of musty odor producing Phormidium tenue by biofilm was examined. The biofilm was scraped from a honeycomb-like tube settled in the biological treatment facility of Kasumigaura Waterworks and P. tenue which produces 2-methylisoborneol (MIB) was isolated from Lake Kasumigaura. P. tenue of 80 mgl-1 and 103μgl-1 of the mllsty odor compound, MIB were degraded by the biofilm within 8 days. It was found that several protozoa such as Monas guttula, Holostica sp., Tetrahymena sp., and Stylonychia sp. in the biofilm actively predated on the P. tenue, subsequently the eluted MIB from the strains was perfectly assimilated by bacteria in the biofilm.