bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Integrated Dynamic Model and Control System for Activated Sludge Wastewater Treatment Plants Part II — Control Systems
Authors: Vitasovic Zdenko , Andrews John F. 
Published: March 2019

Abstract
Part I of this paper has presented an integrated dynamic model for the activated sludge process consisting of a mixture of standard engineering equations and theoretical mechanistic models. In this, Part II of the paper, the integrated model is used in computer simulations to explore process dynamics and integrated control strategies. The interactions of six individual controllers: DO, MCRT, the STOUR profile, settler flow, the compressor, and a pump station have been studied as well as interactions between plant components and design and operation. Among these interactions are those between fluctuations in the influent flow rate and the solids-liquid separator and STOUR in each portion of the biological reactor. The use of a variable volume biological reactor is proposed to damp the effects of flow rate fluctuations on the separator and thus improve effluent quality. Estimation of the STOUR profile and its use in process control is proposed for producing a sludge with more consistent settling characteristics. It is proposed that the use of separator flow control, air flow rate distribution, and step feed capabilities for process control be further explored by field studies for possible incorporation in new plant designs.
The Adaptation of Anaerobic Granulated Bed to Changes in Loading Rate and Liquid Upflow Velocity in UASB Reactors
Authors: Kosaric N. , Blaszczyk R. , Orphan L. 
Published: March 2019

Abstract
Four 20L UASB reactors, R1, R2, R3 and R4 were operated at different upflow velocities of 0.25, 1.0, 1.5, and 0.5 m/h, respectively. Changes in loading rate were achieved by removing part of granules from the bed at a constant volumetric feed rate of 6.2 g COD/(L day).
It was found that the granulated bed may adapt to the increased organic loading rate up to about 1.6 kg COD/(kg VSS day) and achieve a 100% conversion of the COD present (composed of volatile fatty acids). Increasing the loading rate over the above value can bring about a decreased COD conversion. At the organic loading rate of 1.6 kg COD/(kg VSS day), the accumulation of granules in reactors R1 and R4 was observed. At the same loading rate, no accumulation of granules was observed in reactor R2 (within 40 days) and in reactor R3 (within 55 days).
It was also found that a great number of large granules were washed out from reactors R1 and R4 when the loading rate of about 0.7 kg COD/(kg VSS day) was maintained for about 70 days.
A Comparison of the Aquatic Toxicity of Fenitrothion Flowable and Fenitrothion Liquid Technical Formulations
Authors: Ernst W.R. , Doe K.G. 
Published: March 2019

Abstract
Fenitrothion, a popular spruce budworm (Choristoneura fumiferarna) insecticide, has recently been produced as a “flowable” formulation which consists of finely milled particles of the active ingredient in suspension. In order to determine if such a formulation change could alter the chemical’s toxicity and bioconcentration potential to non-target aquatic fauna, a series of bioassays was undertaken. In acute (48- and 96-h LC50s) tests using rainbow trout (Oncorhynchus mykiss), threespine stickleback (Gasterosteus aculeatus), freshwater clams (Anodonta spp.), blue mussels (Mytilus edulis) and the water flea (Daphnia magna), the toxicity of conventional fenitrothion (liquid technical) formulations was not substantially different from that of the “flowable” (particulate) formulation. The exception was that the flowable formulation was less toxic than the liquid technical formulation to the freshwater clam by a factor of 1/3 to 1/5.
Bioconcentration factors to blue mussels for the flowable formulation (15 to 36) were approximately 1/8 to 1/2 the blue mussel bioconcentration factors previously reported for the liquid technical formulations. The results indicate that the flowable formulation does not represent an increased hazard to the aquatic organisms tested, compared with the conventional liquid technical formulations.
Impact of an Acid Spill on the Resident Fauna of the York River and its Recovery
Authors: Prairie R. , Schiefer K. , Moulins L.J. , Chapados V. 
Published: March 2019

Abstract
As a result of a sulphuric acid spill in June 1982 at the Mines Gaspé operation in Murdochville, Québec, water quality of effluents being discharged into the headwaters of the York River was temporarily impaired. It rapidly became apparent that the aquatic fauna of this important Atlantic salmon river had been affected in some areas. This paper provides an overview of the results obtained in biological studies (Atlantic salmon population and benthic communities) carried out by Beak Consultants Ltd. and Noranda Technology Centre, annually, from 1982 to 1985. The biological and water chemistry surveys carried out during this four-year period indicated a short duration event of high dissolved metal levels, primarily copper, shortly after the spill, followed by a rapid improvement in water quality. Both the aquatic macroinvertebrate benthos and fish life in the river were negatively impacted. The nature and degree of this impact as well as the subsequent recolonization of aquatic habitats by both groups were observed and documented.
The most affected aquatic groups in 1982 were the youngest salmon age classes (0+ and 1+) along with the intermediate and sensitive benthic communities. This impact was mainly observed in the upper and middle river section. Maintenance of suitable water quality during the following years has permitted excellent survival rates for juvenile salmon and recolonization of benthic habitats by sensitive species. This has contributed to the gradual re-establishment of a natural aquatic fauna in the York River.
More recent surveys carried out since 1985 confirm that the quality of the York River ecosystem has been maintained and suggest that the survival rates observed for juvenile salmon are higher than the theoretical values usually used in salmon production models.
Coliphage Presence in Various Types of Potable Water in Thailand
Authors: Sivaborvorn Komol , Dutka B.J. 
Published: March 2019

Abstract
Three types of drinking water used in Thailand, tap water, rain water and deep well water (200 m) were tested for bacteriological and coliphage content. 13.5% of the samples contained only coliphage and 13% contained both coliphage and total coliforms. The incidence of coliphage in these potable water supplies reflect the probability of human pathogenic virus also surviving in these waters. The H2S paper-strip test was found to be an equally sensitive indicator of coliform presence compared to MF and MPN total coliform procedures.
The Saguenay Fjord: A Third Factor in the Toxic Chemical Contamination of the St. Lawrence River Estuary
Authors: Allan R.J. 
Published: March 2019

Abstract
The Saguenay Fjord enters the north shore of the St. Lawrence River estuary. The St. Lawrence River is one source of a variety of toxic metals and organic chemicals to its estuary. Some of these chemicals are transported by the river from its source in Lake Ontario and others are added along its course. However, the second major source of water inflow to the St. Lawrence Estuary is the Saguenay Fjord, which is by no means free of contamination. This paper overviews the types of toxic metals and organic chemical contamination and sources in the fjord proper and upstream in its drainage basin. The principal contaminants recorded in bottom sediments are polyaromatic hydrocarbons and mercury. An extensive forest products industry may also be a source of toxic chlorinated organic chemicals. The combined (peak) inputs of these chemicals to the Saguenay Fjord system was in the past and may have continued for many years, even decades. The relationship between the type of contaminants introduced in the past to the St. Lawrence estuary by the St. Lawrence River and the Saguenay Fjord may have implications concerning contamination of the beluga whale population which is located most frequently in the estuary near the fjord inflow.
Trends in Nutrients, Major Ions and Physical Water Quality Parameters in the Niagara River During the 1977–87 Period
Authors: Kuntz K.W. , Tsanis I.K. 
Published: March 2019

Abstract
This paper presents the seasonal and annual variations of the physical parameters, nutrients and major ions in the Niagara River for a period of eleven years, 1977–87. The discharge during this period was found to be steadily increasing and as a consequence the specific conductance was decreasing due to the higher dilution effect, as well as the lower concentrations of chloride and sodium. High concentrations of total phosphorus during the winter months corresponded with high turbidity. In addition, a steady decrease in total phosphorus concentrations was observed until 1984, while during the rest of the period concentrations were increasing. Nitrate nitrogen concentrations were found to be steadily increasing during the entire period except for 1987. Seasonal cycles of specific conductance, calcium, alkalinity, magnesium, and sulphate all showed decreases in April, May and June, during the high discharge period. Both chloride and sodium concentrations have decreased substantially during the 1977–85 period, the result of upstream industrial input decreases, but concentrations since then have levelled out.
Treatment of Oily Waters Using Peat
Authors: Viraraghavan T. , Mathavan G.N. 
Published: March 2019

Abstract
Peat offers itself as an effective medium in the treatment of oily waters, due to its known capacity to remove oil and its abundant availability in Canada. Horticultural peat produced by the Saskatchewan Minerals was used in this study to assess its potential for the removal of oil from various oil-in-water emulsions. The representative oil-in-water emulsions included the following: (1) Medium viscous (130 cP) standard mineral oil (SMO), (2) low viscous (50 cP) Midale crude oil (MCO), cutting oil (CO) and (4) refinery effluent (RE).
Batch kinetic studies were conducted to identify equilibrium time and isotherm patterns. The adsorption of oil by peat was well represented by the BET isotherm compared to the Langmuir and the Freundlich equations. Column studies were conducted using a 100 mm diameter, 600 mm long acrylic pipe with 300 mm depth peat bed. Initially eight-hour tests were run for three different flow rates of 12, 48 and 300 mL/min (2.13, 8.52 and 53.28 m/d). These column studies showed that removal of oil varied between 34 and 99 percent depending upon the influent oil concentration, the type of emulsion, and the flow rate.
Breakthrough studies were undertaken for an optimum flow rate of 50 mL/min (8.88 m/d) for SMO and MCO and 25 mL/min (4.44 m/d) for CO and RE to assess the ultimate capacity of peat under dynamic conditions. The data obtained from breakthrough studies were applied to scale-up and kinetic models to estimate the amount of peat required to remove oil from a flow rate of 150 m3/d of oily waters.
A Phytotoxicity Biosensor using Photosynthetic Membranes
Authors: Purcell Marc , Carpentier Robert 
Published: March 2019

Abstract
The potential of a photoelectrochemical cell employing photo-synthetic membranes in an application as a phytotoxicity biosensor is demonstrated. In this cell, a small volume (80 μl) of isolated thylakoid membranes is used to produce a photocurrent. The reduced species produced during photosynthetic electron transport are oxidized by soluble electroactive mediators which are reoxidized by a platinum working electrode. The photocurrent generated was inhibited by relatively low concentrations of herbicides, nitrite, sulfite and several heavy metals due to their inhibitory effect on photosynthetic electron transport. The cell sensitivity was enhanced when chlorophyll concentration was reduced and artificial electron acceptor concentration was increased.
Simple Models of the Circulation, Dissolved Metals, Suspended Solids and Nutrients in Halifax Harbour
Authors: Petrie Brian , Yeats Philip 
Published: March 2019

Abstract
Salinity data collected in monthly surveys over a two year period are used to model the horizontal circulation and vertical exchange in Halifax Harbour. The circulation is characterised by near-surface outflow and subsurface inflow at rates of order 1 cm s−1; vertical velocities are found to be up to 2 m d−1. Boundary conditions for 5 metals, suspended solids and nutrients are used with the circulation model to derive the distributions of these variables in the Harbour. The modelled distributions of Cu, suspended solids, nitrate and phosphate agree well with the observations. The derived distribution of Mn, Zn, Pb and Hg are less satisfactory, the differences arising because of the chemical dynamics of the former and the uncertainty of the boundary conditions for the latter three. Nitrogen, mostly in the form of ammonia, from sewage can account for a significant portion of the primary productivity in the Harbour; however, the model overestimates the observed winter concentrations of ammonia by a factor of 3.
Fate of Trifluralin in Anaerobic Sediment from an Alberta Farm Dugout
Authors: Fox M.E. , Tol C. Van , Prepas E.E. , Nagy E. , Murphy T.P. 
Published: March 2019

Abstract
Anaerobic surficial sediment from a farm dugout in central Alberta was treated with sufficient Treflan™6 herbicide added to yield 5 µg/g dry weight trifluralin (TRF) and maintained in the laboratory under anaerobic conditions. Samples collected at intervals over 32 days were analysed for trifluralin and related compounds. More than 95% of the trifluralin disappeared within two days but levels then stabilized and even increased slightly, suggesting regeneration from an initially unextractable form. A product of reductive transformation, α, α, α-trifluoro-5-nitro-N4, N4-dipropyltoluene-3,4-diamine (R1TRF), was identified. R1TRF was found from day 0, reached a maximum of 0.3 µg/g, then slowly declined over the duration of the study. A second reductive transformation product, α, α, α-trifluoro-N4, N4-dipropyltoluene-3,4,5-triamine (R2TRF), was also identified. This compound appeared transiently in low concentrations between day 2 and day 16 of the study. The findings of this study were used to explain the bioaccumulation of TRF and related compounds in leeches from a Treflan treated dugout.
Survival of Selected Aquatic Insects Exposed to Methoxychlor Treatment of the Saskatchewan River System
Authors: Dosdall Lloyd M. 
Published: March 2019

Abstract
Survival of aquatic insects was compared before and after exposure to methoxychlor treatment (0.3 mg·L−1 for 15 min) of the Saskatchewan River system at three sites downstream from injection (21, 38, and 107 km). Species studied were Isoperla bilineata (Say), Isoperla longiseta Banks (Plecoptera: Perlodidae), Hydropsyche alternans (Walker), Hydropsyche occidentalis Banks (Trichoptera: Hydropsychidae), Stenonema termination (Walsh), and Stenacron interpunctatum (Say) (Ephemeroptera: Heptageniidae). Survival of individuals exposed to treatment was species-dependent and related to distance from the methoxychlor injection point. At the km 21 site, survival of four of the six species studied declined significantly (P &lt; 0.05) over 15 days, relative to controls. At the km 38 and 107 sites, survival was not affected significantly (P &gt; 0.05) for any species studied.
Mercury and Organochlorinated Hydrocarbons in Surficial Sediments of the St. Francis
Authors: Sloterdijk Harm H. 
Published: March 2019

Abstract
In order to evaluate the role of Lake St. Francis as a depositional zone for toxic substances coming from Lake Ontario and the international section of the St. Lawrence River, a sediment survey was carried out in the early eighties. Samples from 98 stations were analyzed for particle size, organic carbon, mercury (Hg), polychlorinated biphenyls (PCB’s), and organo-chlorinated pesticides, and those from 10 stations for chlorobenzenes, pentachlorophenol, and polybrominated biphenyls. Only PCB’s and Hg were found at high concentrations, up to 1900 and 1500 ng·g−1, respectively. Although Lake Ontario remains a general source of contaminants (especially PCB’s and mirex) for the Quebec stretch of the St. Lawrence River, its contribution to Lake St. Francis is of less importance than that of local sources along the Canada/USA international section of the rivers, such as Cornwall (Hg) and the Massena area (PCB’s).
Evaluation of a Small-Scale Biofilm Process for Wastewater Treatment
Authors: Banerji Shankha K. , Cho Kye-Min 
Published: March 2019

Abstract
An innovative aerated biofilm process (ABP) was evaluated under laboratory conditions to treat synthetic wastewater. The particular system performed well (&gt;90% BOD removal) at fairly high BOD loading conditions (16.7 g BOD m−2d−1). The process did not require a separate secondary settling chamber to produce an effluent low in suspended solids (&lt;10 mgL−1). The amount of sludge produced was lower than other comparable systems — 0.3g total solids were produced per g of BOD removed at an organic removal rate of 8 g BOD m−2d−1. This process could be adopted for treating wastewater in small systems.
Sorption and Desorption of Cu(II) by Ganoderma Lucidum
Authors: Matheickal Jose T. , Iyengar Leela , Venkobachar C. 
Published: March 2019

Abstract
Experimental results on the uptake of Cu(II) by Ganoderma lucidum (M) and its alkali treated residue (Mc) indicated that the metal binding is a fast reaction. The pH of the sorption media affect the metal binding capacity. The equilibrium data for both M and Mc appear to fit well, the Langmuir isotherm. A simple mathematical model is developed based on adsorption equilibria and mass balance to predict the concentration of metal that can be desorbed. Disagreement between the model predicted and experimental desorption equilibria indicated that biosorption of Cu(II) by M and Mc is irreversible. EDTA and HCl are efficient eluants capable of recovering almost all the bound metal.
Aquatic Environmental Aspects of Non-Pesticidal Organotin Compounds
Authors: Maguire R. James 
Published: March 2019

Abstract
Non-pesticidal organotin compounds in Canadian commerce are those of monomethyltin, dimethyltin, monobutyltin, dibutyltin, monooctyltin and dioctyltin. A review is presented of the uses, methods of analysis, environmental occurrence and aquatic toxicity of these compounds, which are scheduled for assessment under the Canadian Environmental Protection Act. It is likely that the most important non-pesticidal route of entry of these compounds to the environment will be through leaching of organotin-stabilized poly(vinyl chloride) by water. Monomethyltin and dimethyltin are widespread in the global environment. Monobutyltin and dibutyltin have been found frequently in harbours, marinas and shipping channels in Canada and elsewhere, arising largely as degradation products from the use of the antifouling agent tributyltin which is now regulated in Canada. There are few reports in the literature on the occurrence of butyltin species as a result of non-pesticidal uses or uses of tributyltin other than as an antifouling agent. Monooctyltin and dioctyltin have not been found to date in Canada or elsewhere in environmental samples. Judging from concentrations which have been reported to date, it appears that the mono- and di-methyltin, butyltin and octyltin species pose no threat to aquatic organisms in Canada vis-à-vis acute toxicity. Data on the persistence of these species in aquatic environments are in some cases fragmentary or non-existent, but in general it appears that these species would not be persistent in aquatic environments, with half-lives estimated to be less than a few months at 20°C.
A Review of Approaches to Achieve Low Effluent Phosphorus Concentrations
Authors: Nutt Stephen G. 
Published: March 2019

Abstract
Total phosphorus (TP) concentration limits substantially lower than currently imposed on municipal WPCP effluents may need to be achieved in specific areas of Ontario to protect water quality. The capability to achieve low effluent TP levels (&lt;0.20 mg/L) on a consistent basis has not been widely demonstrated in Ontario. To determine the feasibility of achieving the concentration limits being considered, a review of the capabilities of proven and innovative technologies was undertaken.
As a result of this review, it was recommended that: (i) full-scale demonstration tests of the capability of post-precipitation plus filtration to achieve effluent TP levels less than 0.1 mg/L should be undertaken at several selected Ontario WPCPs; (ii) full-scale testing of multiple-point chemical precipitation operating options (i.e. pre-precipitation plus simulation precipitation, pre-precipitation plus post-precipitation, etc.) should be undertaken at selected Ontario WPCPs to define the capabilities and benefits associated with the various operational modes; (iii) the cost and effectiveness of post-precipitation in conjunction with tertiary filters should be compared to that of post-precipitation in conjunction with tertiary solids contact flocculator clarifiers and post-precipitation in conjunction with filters and solids contact clarifiers to determine the most appropriate process train for meeting low effluent TP limits; (iv) the cost and effectiveness of activated alumina for polishing municipal treatment plant effluents to TP concentrations below 0.1 mg/L should be compared to that of conventional chemical post-precipitation processes; and, (v) the potential impacts of high chemical dosages on the sludge management processes (digestion and land utilization) and on effluent toxicity should be evaluated.
Destruction of Pollutants and Microorganisms in Water by UV Light and Hydrogen Peroxide
Authors: Sundstrom D.W. , Weir B.A. , Barber T. A. , Klei H. E. 
Published: March 2019

Abstract
This project investigated the destruction of organic compounds and microorganisms in water by ultraviolet catalyzed oxidation using hydrogen peroxide as the oxidizing agent. The combination of UV light and hydrogen peroxide was effective in decomposing all of the organic compounds studied. The rates of destruction increased with increasing peroxide concentration and UV light intensity, and were highly dependent on chemical structure. The destruction of mixtures of organic compounds showed strong interactions between reacting components. The inactivation of E. coli and B. subtilis spores by UV light and/or hydrogen peroxide was studied in flat plate reactors. By using thin liquid films, the combination of UV light and peroxide greatly increased the rates of inactivation of both microorganisms. The results were correlated by a mixed second order kinetic model.
Degradation of Nitrobenzene and Nitrophenols in Homogeneous Aqueous Solution
Authors: Lipczynska-Kochany Ewa 
Published: March 2019

Abstract
Degradation reactions of aqueous nitrobenzene (1), 2-nitrophenol (2), and 2,4-dinitrophenol (3) by means of the photolysis in the presence of the Fenton reagent (FeCL2/H2O2) (I) were investigated. The results were compared with those for 4-nitrophenol (4) as well as for direct photolysis (II), the photolysis in the presence of hydrogen peroxide (III) and the dark Fenton reaction (IV) of (1)–(3), reported elsewhere. In all the cases, decomposition of the aromatic nitrocompounds was observed. The best results were obtained when the solutions of nitrophenols 2–4, containing the Fenton reagent, were irradiated with the polychromic UV light. The rates of the compounds 1–4 degradation depend on their electronic structures in the ground and excited states. The mechanisms of the degradation of 1–4 by means of direct photolysis, the Fenton reaction, the photochemical reactions in the presence of hydrogen peroxide and the Fenton reaction are discussed. The developed method I is concluded to be more effective than II–IV, and therefore recommended for the elimination of the compounds 1–4 from waters and wastewaters.