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The present work involves a study on the thermal conductivity of nanoparticle-oil suspensions for three types of nanoparticles, namely, carbon nanotubes (CNTs), exfoliated graphite (EXG), and heat treated nanofibers (HTT) with PAO oil as the base fluid. To accomplish the above task, an experimental analysis is performed using a modern light flash technique (LFA 447) for measuring the thermal conductivity of the three types of nanofluids, for different loading of nanoparticles. The experimental results show a similar trend as observed in literature for nanofluids with a maximum enhancement of approximately 161% obtained for the CNT-PAO oil suspension. The overall percent enhancements for different volume fractions of the nanoparticles are highest for the CNT-based nanofluid, followed by the EXG and the HTT. The findings from this study for the three different types of carbon nanoparticles can have great potential in the field of thermal management. [ABSTRACT FROM AUTHOR]

The catalytic activity of Mn2O3, FeOOH and CeO2 nanoparticles was evaluated in the treatment of a synthetic petroleum refinery wastewater (SPRW) using O3 in a discontinuous reactor at 25°C and pH 5.5. The mineralization and partial chemical oxidation rates of SPRW using these metal oxides are in the same order of magnitude, and the catalytic activity in the mineralization of SPRW decreased in the order Mn2O3 > CeO2 > FeOOH. The mineralized fraction progressively increased with time in the catalytic process while in the non-catalytic process it remained constant. The effect of the operational conditions on the mineralization and partial chemical oxidation rates using Mn2O3 was investigated in detail. The mineralization rate was found to be lower than the partial oxidation rate due to the formation of partially oxidized by-products, and this is dependent on the solids dosage and pH. An investigation of the mechanism demonstrated that the enhancement effect could be attributed to the introduction of the manganese oxide nanoparticles, which could promote the utilization of O3 and/or enhance the formation of free radicals (•OH, •O2H and •O2−) on the solid surface and further accelerate the degradation of the organic compounds present in the wastewater. [ABSTRACT FROM AUTHOR]

The diversification of Canadian oil sands markets is imperative for the long-term economic growth of oil sands products. To ensure a competitive place in the global market, supply chain costs of oil sands must be as low as possible. This study conducts a comparative techno-economic analysis of potential pathways for the transportation of Canadian oil sands products (synthetic crude oil and diluted bitumen) to seaport destinations in the Asia-Pacific region. We developed data-intensive techno-economic models to estimate total supply chain costs from the production site in Alberta to ports in China, Japan, and India. Four pathways were developed using production (steam assisted gravity drainage), transportation (production-upgrader-port in Vancouver), upgrading, and shipping operations. A sensitivity analysis was conducted to identify cost ranges with their occurrence probability measures and evaluate the effect of key parameters for each stage of operation. Supply chain costs (C$ per barrel of bitumen) to China, Japan, and India are from 61–87, 60–86, and 62–90, respectively. Overall supply chain costs of dilbit (a blend of bitumen and diluent) and synthetic crude oil (SCO) are affected most by production and upgrading costs. The production and upgrading costs are influenced by capital cost, while pipeline lifetime and capacity highly impact transportation (pipeline) and shipping costs, respectively. The developed models can be used to predict total supply chain costs of different pathways in Canadian oil sand markets. [ABSTRACT FROM AUTHOR]

Esters were synthesized using synthetic petroleum acids and ethylene glycol. The esterification was carried out in various types of reactors in the presence of commercial Zeokar-600 catalyst. Physicochemical properties of the synthesized esters and of 5 and 10% compounds of these esters with the diesel fraction were determined. The esters obtained can be used as additives to diesel fuels to improve their performance properties. [ABSTRACT FROM AUTHOR]

This paper proposes a new integrated model for simultaneous design optimization of upgrading plants in the oil sands industry and the associating utility plants. In the past, work has been mainly focused on the energy infrastructure of upgrading plants, and predesigned power and hydrogen plants were considered as utility plants. The novelty of this work is the incorporation of a detailed polygeneration energy system model with the bitumen upgrading plant model. In this way, optimal configurations can be found to meet the various energy requirements of upgrading plants in the oil sands industry. On the basis of the proposed optimization model, optimal configurations under different scenarios are discussed. Effects of upgrading plant capacity, being able to export power to the public grid, natural gas and electricity prices, and the margin between diluted bitumen and synthetic crude oil prices are studied. According to the results, the presented model is a practical tool to design the optimal upgrading plant and its utility plant for the oil sands industry. [ABSTRACT FROM AUTHOR]

In this study, the total energy requirements associated with the production of bitumen from oil sands and its upgrading to synthetic crude oil (SCO) are modeled and quantified. The production scheme considered is based on the commercially applied steam assisted gravity drainage (SAGD) for bitumen extraction and delayed coking for bitumen upgrading. In addition, the model quantifies the greenhouse gas (GHG) emissions associated with the production of energy required for these operations from technologies utilized in the currently existing oil sands energy infrastructure. The model is based on fundamental engineering principles, and Aspen HYSYS and Aspen Plus simulations. The energy demand results are expressed in terms of heat, power, hydrogen, and process fuel consumption rates for SAGD extraction and bitumen upgrading. Based on the model’s output, a range of overall energy and emission intensity factors are estimated for a bitumen production rate of 112,500 BPD (or 93,272 BPD of SCO), which were determined to be 262.5–368.5 MJ/GJ SCO and 14.17–19.84 gCO 2 /MJ SCO , respectively. The results of the model indicate that the majority of GHG emissions are generated during SAGD extraction (up to 60% of total emissions) due to the combustion of natural gas for steam production, and the steam-to-oil ratio is a major parameter affecting total GHG emissions. The developed model can be utilized as a tool to predict the energy demand requirements for integrated SAGD/upgrading projects under different operating conditions, and provides guidance on the feasibility of lowering GHG emissions associated with their operation. [ABSTRACT FROM AUTHOR]

The Fischer-Tropsch synthesis was carried out over cobalt catalysts using gas from oil shale as a model. A broad hydrocarbon fraction can be obtained over cobalt catalysts using model mixtures (CO + CO + H + N ) from Leningrad and Kashpir oil shale products. A study was carried out on the effect of the synthesis gas composition, support and promoter type, temperature, pressure, and volumetric stock feed rate on catalyst efficiency, carbon monoxide conversion, as well as the selectivity and yield of the liquid products. Liquid hydrocarbon selectivity up to 88.7% was achieved with low methane selectivity (3.3%). The hydrocarbons obtained show chain growth probability up to 0.87. [ABSTRACT FROM AUTHOR]

In this study, the effect of Ca and Ce and Synergetic effects of these promoters on the catalytic properties of 15wt.% Co/CNTs catalyst in Fischer-Tropsch synthesis (FTS) are investigated. Catalysts with atomic ratios of 100Co, 100Co/2Ca, 100Co/2Ce and 100Co/1Ca/1Ce were prepared. Catalysts were characterized by BET, TPR, XRD and H2 chemisorption techniques. The FTS performance of the catalysts was studied in a fixed-bed micro-reactor under conditions of 220°C, 18bar, and H2/CO = 2 (v/v). Addition of small amounts of Ce to the Co/CNTs catalyst shifted both TPR peaks significantly to the lower temperatures. According to XRD results, average crystallite sizes of Co decreased in Co-Ce/CNTs and Co-Ce-Ca/CNTs catalysts. In Ca promoted catalyst in comparison with unprompted catalyst, the FTS activity decreased slightly and C5+ selectivity increased by about 12.5%. Addition of Ce increased the FTS activity by about 10.3% and increased C5+ selectivity from 72% to 77%. Synergistic effects of Ca and Ce in Co-Ca-Ce/CNTs, caused significant increase of C5+ selectivity to 80%. Explanations for the selectivity trends are provided based on the effects of Ce, Ca on structural and electronic properties of Co/CNTs catalysts. [ABSTRACT FROM AUTHOR]

In this paper, the influence on the system performance and greenhouse gas (GHG) emissions of different biomass pretreatment methods before gasification and Fischer-Tropsch (FT) crude production was evaluated. Entrained flow gasification has the benefit of producing a practically tar-free synthesis gas with nearly complete carbon conversion. This gasifier type requires a relatively dry fuel, with small particle size, at high pressure. The size can be acquired by milling, which is energy intensive and feeding is challenging. Torrefaction of biomass facilitates milling; it thus requires less electricity, however, the torrefaction process requires heat. Pyrolysis decomposes the biomass into gaseous, liquid, and solid parts, respectively. This further makes feeding easier, but comes with a greater heat demand than torrefaction. The impact of the different pretreatment methods on the overall energy system has been evaluated using process integration methodology. The results show that the excess heat from an FT process with a biomass input of 300 MW can replace the bark boiler in a large chemical pulp and paper mill, producing 350,000 tonnes of bleached paperboard annually. With the preconditions given for this study, thermal pretreatment of biomass may be beneficial in terms of wood-to-FT crude efficiency, with efficiencies up to 68 %, assuming 40 % electrical efficiency. Pretreatment using pyrolysis performed the best in regards to GHG emissions, if CO from acid gas removal was vented, while milling, with an annual reduction of around 700,000 tonnes of CO,, had the best results if the CO was captured and sequestrated. [ABSTRACT FROM AUTHOR]

Mobile distributed pyrolysis facilities have been proposed for delivery of a forest residue resource to bio-fuel facilities. This study examines the costs of producing hydrogen or synthetic petrol (gasoline) and diesel from feedstock produced by mobile facilities (bio-oil, bio-slurry, torrefied wood). Results show that using these feedstock can provide fuels at costs competitive to conventional bio-fuel production methods using gasification of a woodchip feedstock. Using a bio-oil feedstock in combination with bio-oil steam reforming or bio-oil upgrading can produce hydrogen or petrol and diesel at costs of 3.25 $ kg-1or 0.86 $ litre-1, respectively, for optimally sized bio-fuel facilities. When compared on an energy basis ($ GJ-1), hydrogen production costs tend to be lower than those for synthetic petrol or diesel production across a variety of bio-fuel production pathways. [ABSTRACT FROM AUTHOR]