The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform
Julia M. Foght - One of the best experts on this subject based on the ideXlab platform.
-
Draft genome sequences of campylobacterales (epsilonproteobacteria) obtained from methanogenic oil sands tailings pond metagenomes.
Genome Announcements, 2014Co-Authors: Julia M. FoghtAbstract:ABSTRACT Draft genome sequences of two Campylobacterales (Sulfurospirillum sp. strain SCADC and Sulfuricurvum sp. strain MLSB [Mildred Lake Settling Basin]) were obtained by taxonomic binning of metagenomes originating from an oil sands tailings pond. Both genomes contain soxABXYZ genes involved in sulfur oxidation, highlighting their potential roles in sulfur cycling in oil sands tailings ponds.
-
Mature fine tailings from oil sands processing harbour diverse methanogenic communities.
Canadian Journal of Microbiology, 2010Co-Authors: Tara Penner, Julia M. FoghtAbstract:Processing oil sands to extract bitumen produces large volumes of a tailings slurry comprising water, silt, clays, unrecovered bitumen, and residual solvent used in the extraction process. Tailings are deposited into large Settling Basins, where the solids settle by gravity to become denser mature fine tailings (MFT). A substantial flux of methane, currently estimated at ~40 million L/day, is being emitted from the Mildred Lake Settling Basin. To better understand the biogenesis of this greenhouse gas, the methanogenic consortia in MFT samples from depth profiles in 2 tailings deposits (Mildred Lake Settling Basin and West In-Pit) were analyzed by constructing clone libraries of amplified archaeal and bacterial 16S rRNA genes. The archaeal sequences, whose closest matches were almost exclusively cultivated methanogens, were comparable within and between Basins and were predominantly (87% of clones) affiliated with acetoclastic Methanosaeta spp. In contrast, bacterial clone libraries were unexpectedly dive...
-
a first approximation kinetic model to predict methane generation from an oil sands tailings Settling Basin
Chemosphere, 2008Co-Authors: Tariq Siddique, Michael D. Mackinnon, Phillip M Fedorak, Rajender Gupta, Julia M. FoghtAbstract:Abstract A small fraction of the naphtha diluent used for oil sands processing escapes with tailings and supports methane (CH 4 ) biogenesis in large anaerobic Settling Basins such as Mildred Lake Settling Basin (MLSB) in northern Alberta, Canada. Based on the rate of naphtha metabolism in tailings incubated in laboratory microcosms, a kinetic model comprising lag phase, rate of hydrocarbon metabolism and conversion to CH 4 was developed to predict CH 4 biogenesis and flux from MLSB. Zero- and first-order kinetic models, respectively predicted generation of 5.4 and 5.1 mmol CH 4 in naphtha-amended microcosms compared to 5.3 (±0.2) mmol CH 4 measured in microcosms during 46 weeks of incubation. These kinetic models also predicted well the CH 4 produced by tailings amended with either naphtha-range n -alkanes or BTEX compounds at concentrations similar to those expected in MLSB. Considering 25% of MLSB’s 200 million m 3 tailings volume to be methanogenic, the zero- and first-order kinetic models applied over a wide range of naphtha concentrations (0.01–1.0 wt%) predicted production of 8.9–400 million l CH 4 day −1 from MLSB, which exceeds the estimated production of 3–43 million l CH 4 day −1 . This discrepancy may result from heterogeneity and density of the tailings, presence of nutrients in the microcosms, and/or overestimation of the readily biodegradable fraction of the naphtha in MLSB tailings.
-
A first approximation kinetic model to predict methane generation from an oil sands tailings Settling Basin
Chemosphere, 2008Co-Authors: Tariq Siddique, Michael D. Mackinnon, Phillip M Fedorak, Rajender Gupta, Julia M. FoghtAbstract:A small fraction of the naphtha diluent used for oil sands processing escapes with tailings and supports methane (CH4) biogenesis in large anaerobic Settling Basins such as Mildred Lake Settling Basin (MLSB) in northern Alberta, Canada. Based on the rate of naphtha metabolism in tailings incubated in laboratory microcosms, a kinetic model comprising lag phase, rate of hydrocarbon metabolism and conversion to CH4was developed to predict CH4biogenesis and flux from MLSB. Zero- and first-order kinetic models, respectively predicted generation of 5.4 and 5.1 mmol CH4in naphtha-amended microcosms compared to 5.3 (±0.2) mmol CH4measured in microcosms during 46 weeks of incubation. These kinetic models also predicted well the CH4produced by tailings amended with either naphtha-range n-alkanes or BTEX compounds at concentrations similar to those expected in MLSB. Considering 25% of MLSB's 200 million m3tailings volume to be methanogenic, the zero- and first-order kinetic models applied over a wide range of naphtha concentrations (0.01-1.0 wt%) predicted production of 8.9-400 million l CH4day-1from MLSB, which exceeds the estimated production of 3-43 million l CH4day-1. This discrepancy may result from heterogeneity and density of the tailings, presence of nutrients in the microcosms, and/or overestimation of the readily biodegradable fraction of the naphtha in MLSB tailings. © 2008 Elsevier Ltd. All rights reserved.
Tariq Siddique - One of the best experts on this subject based on the ideXlab platform.
-
a first approximation kinetic model to predict methane generation from an oil sands tailings Settling Basin
Chemosphere, 2008Co-Authors: Tariq Siddique, Michael D. Mackinnon, Phillip M Fedorak, Rajender Gupta, Julia M. FoghtAbstract:Abstract A small fraction of the naphtha diluent used for oil sands processing escapes with tailings and supports methane (CH 4 ) biogenesis in large anaerobic Settling Basins such as Mildred Lake Settling Basin (MLSB) in northern Alberta, Canada. Based on the rate of naphtha metabolism in tailings incubated in laboratory microcosms, a kinetic model comprising lag phase, rate of hydrocarbon metabolism and conversion to CH 4 was developed to predict CH 4 biogenesis and flux from MLSB. Zero- and first-order kinetic models, respectively predicted generation of 5.4 and 5.1 mmol CH 4 in naphtha-amended microcosms compared to 5.3 (±0.2) mmol CH 4 measured in microcosms during 46 weeks of incubation. These kinetic models also predicted well the CH 4 produced by tailings amended with either naphtha-range n -alkanes or BTEX compounds at concentrations similar to those expected in MLSB. Considering 25% of MLSB’s 200 million m 3 tailings volume to be methanogenic, the zero- and first-order kinetic models applied over a wide range of naphtha concentrations (0.01–1.0 wt%) predicted production of 8.9–400 million l CH 4 day −1 from MLSB, which exceeds the estimated production of 3–43 million l CH 4 day −1 . This discrepancy may result from heterogeneity and density of the tailings, presence of nutrients in the microcosms, and/or overestimation of the readily biodegradable fraction of the naphtha in MLSB tailings.
-
A first approximation kinetic model to predict methane generation from an oil sands tailings Settling Basin
Chemosphere, 2008Co-Authors: Tariq Siddique, Michael D. Mackinnon, Phillip M Fedorak, Rajender Gupta, Julia M. FoghtAbstract:A small fraction of the naphtha diluent used for oil sands processing escapes with tailings and supports methane (CH4) biogenesis in large anaerobic Settling Basins such as Mildred Lake Settling Basin (MLSB) in northern Alberta, Canada. Based on the rate of naphtha metabolism in tailings incubated in laboratory microcosms, a kinetic model comprising lag phase, rate of hydrocarbon metabolism and conversion to CH4was developed to predict CH4biogenesis and flux from MLSB. Zero- and first-order kinetic models, respectively predicted generation of 5.4 and 5.1 mmol CH4in naphtha-amended microcosms compared to 5.3 (±0.2) mmol CH4measured in microcosms during 46 weeks of incubation. These kinetic models also predicted well the CH4produced by tailings amended with either naphtha-range n-alkanes or BTEX compounds at concentrations similar to those expected in MLSB. Considering 25% of MLSB's 200 million m3tailings volume to be methanogenic, the zero- and first-order kinetic models applied over a wide range of naphtha concentrations (0.01-1.0 wt%) predicted production of 8.9-400 million l CH4day-1from MLSB, which exceeds the estimated production of 3-43 million l CH4day-1. This discrepancy may result from heterogeneity and density of the tailings, presence of nutrients in the microcosms, and/or overestimation of the readily biodegradable fraction of the naphtha in MLSB tailings. © 2008 Elsevier Ltd. All rights reserved.
Michael D. Mackinnon - One of the best experts on this subject based on the ideXlab platform.
-
a first approximation kinetic model to predict methane generation from an oil sands tailings Settling Basin
Chemosphere, 2008Co-Authors: Tariq Siddique, Michael D. Mackinnon, Phillip M Fedorak, Rajender Gupta, Julia M. FoghtAbstract:Abstract A small fraction of the naphtha diluent used for oil sands processing escapes with tailings and supports methane (CH 4 ) biogenesis in large anaerobic Settling Basins such as Mildred Lake Settling Basin (MLSB) in northern Alberta, Canada. Based on the rate of naphtha metabolism in tailings incubated in laboratory microcosms, a kinetic model comprising lag phase, rate of hydrocarbon metabolism and conversion to CH 4 was developed to predict CH 4 biogenesis and flux from MLSB. Zero- and first-order kinetic models, respectively predicted generation of 5.4 and 5.1 mmol CH 4 in naphtha-amended microcosms compared to 5.3 (±0.2) mmol CH 4 measured in microcosms during 46 weeks of incubation. These kinetic models also predicted well the CH 4 produced by tailings amended with either naphtha-range n -alkanes or BTEX compounds at concentrations similar to those expected in MLSB. Considering 25% of MLSB’s 200 million m 3 tailings volume to be methanogenic, the zero- and first-order kinetic models applied over a wide range of naphtha concentrations (0.01–1.0 wt%) predicted production of 8.9–400 million l CH 4 day −1 from MLSB, which exceeds the estimated production of 3–43 million l CH 4 day −1 . This discrepancy may result from heterogeneity and density of the tailings, presence of nutrients in the microcosms, and/or overestimation of the readily biodegradable fraction of the naphtha in MLSB tailings.
-
A first approximation kinetic model to predict methane generation from an oil sands tailings Settling Basin
Chemosphere, 2008Co-Authors: Tariq Siddique, Michael D. Mackinnon, Phillip M Fedorak, Rajender Gupta, Julia M. FoghtAbstract:A small fraction of the naphtha diluent used for oil sands processing escapes with tailings and supports methane (CH4) biogenesis in large anaerobic Settling Basins such as Mildred Lake Settling Basin (MLSB) in northern Alberta, Canada. Based on the rate of naphtha metabolism in tailings incubated in laboratory microcosms, a kinetic model comprising lag phase, rate of hydrocarbon metabolism and conversion to CH4was developed to predict CH4biogenesis and flux from MLSB. Zero- and first-order kinetic models, respectively predicted generation of 5.4 and 5.1 mmol CH4in naphtha-amended microcosms compared to 5.3 (±0.2) mmol CH4measured in microcosms during 46 weeks of incubation. These kinetic models also predicted well the CH4produced by tailings amended with either naphtha-range n-alkanes or BTEX compounds at concentrations similar to those expected in MLSB. Considering 25% of MLSB's 200 million m3tailings volume to be methanogenic, the zero- and first-order kinetic models applied over a wide range of naphtha concentrations (0.01-1.0 wt%) predicted production of 8.9-400 million l CH4day-1from MLSB, which exceeds the estimated production of 3-43 million l CH4day-1. This discrepancy may result from heterogeneity and density of the tailings, presence of nutrients in the microcosms, and/or overestimation of the readily biodegradable fraction of the naphtha in MLSB tailings. © 2008 Elsevier Ltd. All rights reserved.
-
Methanogens and sulfate-reducing bacteria in oil sands fine tailings waste
Canadian Journal of Microbiology, 2000Co-Authors: Fervone M Holowenko, Michael D. Mackinnon, Phillip M FedorakAbstract:In the past decade, the large tailings pond (Mildred Lake Settling Basin) on the Syncrude Canada Ltd. lease near Fort McMurray, Alta., has gone methanogenic. Currently, about 60%-80% of the flux of gas across the surface of the tailings pond is methane. As well as adding to greenhouse gas emissions, the production of methane in the fine tailings zone of this and other Settling Basins may affect the performance of these Settling Basins and impact reclama - tion options. Enumeration studies found methanogens (10 5 -10 6 MPN/g) within the fine tailings zone of various oil sands waste Settling Basins. SRB were also present (10 4 -10 5 MPN/g) with elevated numbers when sulfate was avail- able. The methanogenic population was robust, and sample storage up to 9 months at 4°C did not cause the MPN val- ues to change. Nor was the ability of the consortium to produce methane delayed or less efficient after storage. Under laboratory conditions, fine tailings samples released 0.10-0.25 mL CH4 (at STP)/mL fine tailings. The addition of sul- fate inhibited methanogenesis by stimulating bacterial competition.
Phillip M Fedorak - One of the best experts on this subject based on the ideXlab platform.
-
a first approximation kinetic model to predict methane generation from an oil sands tailings Settling Basin
Chemosphere, 2008Co-Authors: Tariq Siddique, Michael D. Mackinnon, Phillip M Fedorak, Rajender Gupta, Julia M. FoghtAbstract:Abstract A small fraction of the naphtha diluent used for oil sands processing escapes with tailings and supports methane (CH 4 ) biogenesis in large anaerobic Settling Basins such as Mildred Lake Settling Basin (MLSB) in northern Alberta, Canada. Based on the rate of naphtha metabolism in tailings incubated in laboratory microcosms, a kinetic model comprising lag phase, rate of hydrocarbon metabolism and conversion to CH 4 was developed to predict CH 4 biogenesis and flux from MLSB. Zero- and first-order kinetic models, respectively predicted generation of 5.4 and 5.1 mmol CH 4 in naphtha-amended microcosms compared to 5.3 (±0.2) mmol CH 4 measured in microcosms during 46 weeks of incubation. These kinetic models also predicted well the CH 4 produced by tailings amended with either naphtha-range n -alkanes or BTEX compounds at concentrations similar to those expected in MLSB. Considering 25% of MLSB’s 200 million m 3 tailings volume to be methanogenic, the zero- and first-order kinetic models applied over a wide range of naphtha concentrations (0.01–1.0 wt%) predicted production of 8.9–400 million l CH 4 day −1 from MLSB, which exceeds the estimated production of 3–43 million l CH 4 day −1 . This discrepancy may result from heterogeneity and density of the tailings, presence of nutrients in the microcosms, and/or overestimation of the readily biodegradable fraction of the naphtha in MLSB tailings.
-
A first approximation kinetic model to predict methane generation from an oil sands tailings Settling Basin
Chemosphere, 2008Co-Authors: Tariq Siddique, Michael D. Mackinnon, Phillip M Fedorak, Rajender Gupta, Julia M. FoghtAbstract:A small fraction of the naphtha diluent used for oil sands processing escapes with tailings and supports methane (CH4) biogenesis in large anaerobic Settling Basins such as Mildred Lake Settling Basin (MLSB) in northern Alberta, Canada. Based on the rate of naphtha metabolism in tailings incubated in laboratory microcosms, a kinetic model comprising lag phase, rate of hydrocarbon metabolism and conversion to CH4was developed to predict CH4biogenesis and flux from MLSB. Zero- and first-order kinetic models, respectively predicted generation of 5.4 and 5.1 mmol CH4in naphtha-amended microcosms compared to 5.3 (±0.2) mmol CH4measured in microcosms during 46 weeks of incubation. These kinetic models also predicted well the CH4produced by tailings amended with either naphtha-range n-alkanes or BTEX compounds at concentrations similar to those expected in MLSB. Considering 25% of MLSB's 200 million m3tailings volume to be methanogenic, the zero- and first-order kinetic models applied over a wide range of naphtha concentrations (0.01-1.0 wt%) predicted production of 8.9-400 million l CH4day-1from MLSB, which exceeds the estimated production of 3-43 million l CH4day-1. This discrepancy may result from heterogeneity and density of the tailings, presence of nutrients in the microcosms, and/or overestimation of the readily biodegradable fraction of the naphtha in MLSB tailings. © 2008 Elsevier Ltd. All rights reserved.
-
Methanogens and sulfate-reducing bacteria in oil sands fine tailings waste
Canadian Journal of Microbiology, 2000Co-Authors: Fervone M Holowenko, Michael D. Mackinnon, Phillip M FedorakAbstract:In the past decade, the large tailings pond (Mildred Lake Settling Basin) on the Syncrude Canada Ltd. lease near Fort McMurray, Alta., has gone methanogenic. Currently, about 60%-80% of the flux of gas across the surface of the tailings pond is methane. As well as adding to greenhouse gas emissions, the production of methane in the fine tailings zone of this and other Settling Basins may affect the performance of these Settling Basins and impact reclama - tion options. Enumeration studies found methanogens (10 5 -10 6 MPN/g) within the fine tailings zone of various oil sands waste Settling Basins. SRB were also present (10 4 -10 5 MPN/g) with elevated numbers when sulfate was avail- able. The methanogenic population was robust, and sample storage up to 9 months at 4°C did not cause the MPN val- ues to change. Nor was the ability of the consortium to produce methane delayed or less efficient after storage. Under laboratory conditions, fine tailings samples released 0.10-0.25 mL CH4 (at STP)/mL fine tailings. The addition of sul- fate inhibited methanogenesis by stimulating bacterial competition.
Rajender Gupta - One of the best experts on this subject based on the ideXlab platform.
-
a first approximation kinetic model to predict methane generation from an oil sands tailings Settling Basin
Chemosphere, 2008Co-Authors: Tariq Siddique, Michael D. Mackinnon, Phillip M Fedorak, Rajender Gupta, Julia M. FoghtAbstract:Abstract A small fraction of the naphtha diluent used for oil sands processing escapes with tailings and supports methane (CH 4 ) biogenesis in large anaerobic Settling Basins such as Mildred Lake Settling Basin (MLSB) in northern Alberta, Canada. Based on the rate of naphtha metabolism in tailings incubated in laboratory microcosms, a kinetic model comprising lag phase, rate of hydrocarbon metabolism and conversion to CH 4 was developed to predict CH 4 biogenesis and flux from MLSB. Zero- and first-order kinetic models, respectively predicted generation of 5.4 and 5.1 mmol CH 4 in naphtha-amended microcosms compared to 5.3 (±0.2) mmol CH 4 measured in microcosms during 46 weeks of incubation. These kinetic models also predicted well the CH 4 produced by tailings amended with either naphtha-range n -alkanes or BTEX compounds at concentrations similar to those expected in MLSB. Considering 25% of MLSB’s 200 million m 3 tailings volume to be methanogenic, the zero- and first-order kinetic models applied over a wide range of naphtha concentrations (0.01–1.0 wt%) predicted production of 8.9–400 million l CH 4 day −1 from MLSB, which exceeds the estimated production of 3–43 million l CH 4 day −1 . This discrepancy may result from heterogeneity and density of the tailings, presence of nutrients in the microcosms, and/or overestimation of the readily biodegradable fraction of the naphtha in MLSB tailings.
-
A first approximation kinetic model to predict methane generation from an oil sands tailings Settling Basin
Chemosphere, 2008Co-Authors: Tariq Siddique, Michael D. Mackinnon, Phillip M Fedorak, Rajender Gupta, Julia M. FoghtAbstract:A small fraction of the naphtha diluent used for oil sands processing escapes with tailings and supports methane (CH4) biogenesis in large anaerobic Settling Basins such as Mildred Lake Settling Basin (MLSB) in northern Alberta, Canada. Based on the rate of naphtha metabolism in tailings incubated in laboratory microcosms, a kinetic model comprising lag phase, rate of hydrocarbon metabolism and conversion to CH4was developed to predict CH4biogenesis and flux from MLSB. Zero- and first-order kinetic models, respectively predicted generation of 5.4 and 5.1 mmol CH4in naphtha-amended microcosms compared to 5.3 (±0.2) mmol CH4measured in microcosms during 46 weeks of incubation. These kinetic models also predicted well the CH4produced by tailings amended with either naphtha-range n-alkanes or BTEX compounds at concentrations similar to those expected in MLSB. Considering 25% of MLSB's 200 million m3tailings volume to be methanogenic, the zero- and first-order kinetic models applied over a wide range of naphtha concentrations (0.01-1.0 wt%) predicted production of 8.9-400 million l CH4day-1from MLSB, which exceeds the estimated production of 3-43 million l CH4day-1. This discrepancy may result from heterogeneity and density of the tailings, presence of nutrients in the microcosms, and/or overestimation of the readily biodegradable fraction of the naphtha in MLSB tailings. © 2008 Elsevier Ltd. All rights reserved.