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ABSTRACT The authors investigated the use of a pilot scale rotating biological contactor (RBC) and a pilot scale sequencing batch reactor (SBR) to nitrify landfill leachate with a mean ammonia nitrogen concentration of 202 mg L−1 and mean... more
ABSTRACT The authors investigated the use of a pilot scale rotating biological contactor (RBC) and a pilot scale sequencing batch reactor (SBR) to nitrify landfill leachate with a mean ammonia nitrogen concentration of 202 mg L−1 and mean BOD5 concentration of 50 mg L−1. The research was conducted under field conditions over a 14 month period. The research showed that, for this type of leachate, the RBC ammonia removal was superior to the SBR ammonia removal. The result appeared to be due to the low solids generation potential of this type of leachate, and the impacts of low temperature on the SBR system. Mixed liquor solids concentration appeared to be the critical factor in determining SBR ammonia removal. Full ammonia removal was achieved at RBC loading rates up to 4.5 g m−2 day−1, a hydraulic retention time of 0.3 days and a temperature of 18 °C. Full ammonia removal was achieved in the SBR unit at ammonia loading rates up to 400 g m−3 day−1 (0.6 g g MLSS−1 day−1), a hydraulic retention time of 0.7 days, and 20 °C. The effect of temperature on the RBC ammonia removal was modeled using the Arrhenius Equation with Θ = 1.111 and R2 = 0.88. Ammonia was effectively removed by the RBC system at temperatures as low as 2 °C. At temperatures exceeding 20 °C, RBC performance appeared to be inhibited. Phosphorus limitation appeared to reduce RBC performance at effluent soluble PO4-P concentrations less than 0.2 mg L−1. RBC mass removal rate was affected by influent ammonia concentration. Artificially increasing the influent ammonia concentration resulted in increased ammonia removal. Neither system effectively removed BOD5, COD, colour or metals. Removal for these parameters ranged from less than 0 to 40%.
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effects of moisture inputs on landfill gas production
During the management of municipal solid wastes there are a number of activities which result in emissions of greenhouse gases (GHGs) which are believed to cause to Global Warming. These are carbon dioxide (CO2), methane (CH4) and nitrous... more
During the management of municipal solid wastes there are a number of activities which result in emissions of greenhouse gases (GHGs) which are believed to cause to Global Warming. These are carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O. As all sectors of society will have to start reducing these emissions, effort is needed to address the greenhouse gas contribution resulting from waste management. A lifecycle analysis was performed to determine the GHG benefit of using composting in an Ontario municipality to divert organic waste (yard trimmings plus industrial organic waste such as lees from wine industry and renderings from animal processing plants) from landfill disposal and to determine the full emissions per tonne from landfilling, incinerating or backyard composting of food scraps. By excluding any carbon sequestering in landfills, it was found that 34,122 tCO2e (tonnes of carbon dioxide equivalent) could be prevented from being emitted over the next 12 years by ...
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Nitrous Oxide Emissions and the Anthropogenic Nitrogen in Wastewater and Solid Waste. [Journal of Environmental Engineering 128, 137 (2002)]. Philip K. Barton, James W. Atwater. Abstract. In the 20th century, human interference ...
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Sorption of endosulphan sulphate in soil organic matter was investigated using Standard Elliot soil humic acid (HA) and soil fulvic acid (FA) at two ionic strengths (0.001 and 0.01). It was observed that divalent calcium ion and ionic... more
Sorption of endosulphan sulphate in soil organic matter was investigated using Standard Elliot soil humic acid (HA) and soil fulvic acid (FA) at two ionic strengths (0.001 and 0.01). It was observed that divalent calcium ion and ionic strength affect the sorption of endosulphan sulphate in HA. All the experiments were carried out at pH 6.7 +/- 0.1. In the presence and absence of calcium (ionic strength 0.001), the solubility enhancement method was used to estimate the sorption coefficients of endosulphan sulphate in HA. For FA, the solubility enhancement method was used to estimate the sorption coefficients at an ionic strength of 0.001 (in the presence of calcium) and 0.01. The presence of calcium was found to significantly enhance (alpha = 0.01) the solubility of endosulphan sulphate in HA. Sorption coefficients at pH 6.7, obtained using the solubility enhancement method, were found to be 10-21 L/g in HA and 6 L/g in FA (in the presence of calcium). Increase in ionic strength from 0.001 to 0.01 decreased the sorption of endosulphan sulphate in HA. The effect of ionic strength and calcium on the sorption of endosulphan sulphate was most satisfactorily explained on the basis of the Donnan volume.
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Remedial and monitoring efforts at the site of a polychlorinated biphenyl (PCB) spill in Regina, Saskatchewan, Canada, has produced information in addition to that found in the original investigation and reported in this journal.... more
Remedial and monitoring efforts at the site of a polychlorinated biphenyl (PCB) spill in Regina, Saskatchewan, Canada, has produced information in addition to that found in the original investigation and reported in this journal. Additional pathways exist for horizontal movement of PCB within the underlying clays and silts. The PCB has moved horizontal at depth apparently under its own head
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Typically, the operation of a conventional fluidized bed relies on the balance of gravitational, buoyancy, and drag forces. In the absence of normal gravity, or under microgravity and variable gravity conditions, the gravitational force... more
Typically, the operation of a conventional fluidized bed relies on the balance of gravitational, buoyancy, and drag forces. In the absence of normal gravity, or under microgravity and variable gravity conditions, the gravitational force must be replaced with an alternative force to restore fluidization. Our work has shown that, given a suitable variable magnetic field design, the resulting magnetic field
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A study on the quality of water distributed within the Greater Vancouver Regional District (GVRD) was carried out to evaluate the effectiveness of previously implemented corrosion controls. In addition, the effect of temperature... more
A study on the quality of water distributed within the Greater Vancouver Regional District (GVRD) was carried out to evaluate the effectiveness of previously implemented corrosion controls. In addition, the effect of temperature fluctuations was investigated to determine if it influenced the efficacy of the control measures. The GVRD was divided into four distribution areas. The Capilano water had no corrosion control treatment. Seymour, Coquitlam, and Newton waters were treated with soda ash, resulting in a pH of 6.8, 6.9, and 8.1, respectively. Standing cold water and running hot and cold water samples were collected from the four zones and analyzed for lead, copper, and zinc concentrations. The source water did not influence the amount of lead at the tap. The source water did influence the amount of copper and zinc at the tap. The highest copper and zinc concentrations were found in the water with the lowest pH (Capilano) and the lowest concentrations in the water with the highes...
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Water quality, Health insurance, Communicable Diseases, Adolescent, Social Class, and 28 moreLogistic Regression, Water Supply, Humans, Child, Infectious Disease, Federal Government, Female, Male, Cohort Study, Young Adult, Infant, Surface Water, Endemic Diseases, Ontario, Newborn Infant, Aged, Middle Aged, Adult, Public health systems and services research, Sewage, Odds ratio, Water Quality, Water Microbiology, Low Income, Sewer System, Logistic Models, Cohort Studies, and Gastrointestinal Diseases
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Remedial and monitoring efforts at the site of a polychlorinated biphenyl (PCB) spill in Regina, Saskatchewan, Canada, has produced information in addition to that found in the original investigation and reported in this journal.... more
Remedial and monitoring efforts at the site of a polychlorinated biphenyl (PCB) spill in Regina, Saskatchewan, Canada, has produced information in addition to that found in the original investigation and reported in this journal. Additional pathways exist for horizontal movement of PCB within the underlying clays and silts. The PCB has moved horizontal at depth apparently under its own head
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Soil vapour transport to indoor air is an important potential exposure pathway at many sites impacted by subsurface volatile organic compounds (VOCs). The inclusion of biodegradation in vadose zone transport models for benzene, toluene... more
Soil vapour transport to indoor air is an important potential exposure pathway at many sites impacted by subsurface volatile organic compounds (VOCs). The inclusion of biodegradation in vadose zone transport models for benzene, toluene and xylene (BTX) and fuel hydrocarbons has been proposed; however, there is still significant uncertainty regarding biodegradation rates and the local effects of buildings or ground
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ABSTRACT
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A multi-layer sampler, developed on the basis of a previously described dialysis membrane technique, was used to passively sample groundwater nitrate (NO3) in two unconfined aquifers. Monthly sampling performed over a 3 month period at... more
A multi-layer sampler, developed on the basis of a previously described dialysis membrane technique, was used to passively sample groundwater nitrate (NO3) in two unconfined aquifers. Monthly sampling performed over a 3 month period at each location has shown the feasibility of using this technique over extended depth, and that it can provide a detailed and highly repeatable characterization of
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Property‐value guarantees (PVGs) by the proponent of a waste facility may be an effective tool to compensate nearby property owners if the facility impacts property values adversely. A review of the theory, and of 13 empirical... more
Property‐value guarantees (PVGs) by the proponent of a waste facility may be an effective tool to compensate nearby property owners if the facility impacts property values adversely. A review of the theory, and of 13 empirical property‐value studies, shows inconsistent results. For a ...
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ABSTRACT Vadose zone in situ diffusion coefficients were measured at a former petrochemical plant (Chatterton research site) using a push-pull test and helium tracer. The test is relatively simple to perform, utilizes relatively... more
ABSTRACT Vadose zone in situ diffusion coefficients were measured at a former petrochemical plant (Chatterton research site) using a push-pull test and helium tracer. The test is relatively simple to perform, utilizes relatively inexpensive materials and field equipment, and requires only a few hours to complete each series of tests. In situ diffusion coefficients are derived using an analytical solution for spherical diffusion from a point source, assuming instantaneous injection of the tracer. The results of push-pull tests conducted at the Chatterton research site indicate that measured effective diffusion coefficients in sand fill with moisture content between 5 and 12% (by weight) ranged from about 0.01 to 0.07 cm2sec−1. A good comparison was obtained between the measured gas-phase tortuosity and that predicted using a common empirical relationship, with measured tortuosity factors consistently being about twice the predicted values. While further comparisons need to be conducted for various moisture contents and different soil types, the results of this study suggest that the push-pull test is an effective tool for estimating diffusion coefficients and can be used to validate empirical relationships for diffusion coefficient.
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Nuisance impacts from waste facilities can aggravate community resistance because odor, noise and visual impacts trigger more serious concerns about impacts on community health, image and property values (1). In order to assess nuisances,... more
Nuisance impacts from waste facilities can aggravate community resistance because odor, noise and visual impacts trigger more serious concerns about impacts on community health, image and property values (1). In order to assess nuisances, initial site selection processes for municipal landfills should use screening models to determine potential nuisance impact zones. Predicted impact zones could provide a basis to plan
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... CHRIS ZEISS Departttletzt of Civil Etlgitreeritzg, The Utzive,:~ity of Albe~rr, Edttlotztot1, Alta. ... minor noise effects, proven impacts are moderate, but spread over a larger distance from the site. ... physical emissions, except... more
... CHRIS ZEISS Departttletzt of Civil Etlgitreeritzg, The Utzive,:~ity of Albe~rr, Edttlotztot1, Alta. ... minor noise effects, proven impacts are moderate, but spread over a larger distance from the site. ... physical emissions, except for the concern about odor at the garbage burner, where no ...