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[en] This paper describes a simplified procedure that has been employed to determine the thickness of char-layer formed in a carbon-phenolic liner used in the divergent section of a rocket nozzle. The procedure consists of determining the local heat flux at the liner surface for a particular surface temperature and then analyzing the coupled heat transfer problem between the gaseous nozzle flow and the composite liner resulting in the formation of char layer
[en] The community consultation process was examined with reference to natural gas from coal (NGC) development in Alberta. It was suggested that NGC has a huge potential in Canada, and can be developed in an environmentally responsible manner which considers all stakeholders. However, water supply shortages and the effects of development on groundwater remain key stakeholder concerns in Alberta. Issues concerning water protection and handling were discussed, along with issues concerning surface disruption during resource development activities. An outline of road needs and pipeline corridors was presented. An outline of a typical NGC compressor station were given. Issues concerning public anxiety over air quality were discussed with reference to flaring and landowner complaints. It was noted NGC is not sour and contains no liquid hydrocarbons or foreign contaminants. A review of government regulations and best practices was presented with regards to flaring. Multi-stakeholder advisory committee practices were reviewed. It was concluded that Alberta is currently using a variety of consultation processes to enable better communications between industry and stakeholders. figs
[en] Forecasts have indicated that despite some uncertainties in Coalbed methane (CBM) technology and concerns over the environmental effects of CBM production, the CBM industry is expected to grow rapidly over the next decade. This conference reviewed a variety of CBM project management strategies adopted by Canadian companies, ranging from initial site assessment through to commercial production. Pipeline and infrastructure requirements for the CBM industry were reviewed, and an overview of CBM regulations was provided. Exploration techniques and recommended practices for CBM hydraulic fracturing were presented. It was noted that in addition to environmental concerns over surface water discharge of CBM produced water, subsurface management issues are being increasingly scrutinized by environmentalists. Various commercialization strategies for CBM production were also reviewed, including well spacing management techniques; infrastructure demands and capitalized costs. Factors to ensure cost-effective high volume production in the shale gas industry were also reviewed. Of the 23 presentations given at this conference, 8 were catalogued separately for inclusion in this database. refs., tabs., figs
[en] Highlights: • Biochar can extend the persistence of acetochlor in soil. • Root was the main enrichment site of acetochlor in plants. • 20 d-aged BC reduced the BCF of acetochlor in plants. • 20 d-aged BC enhanced the BCF of acetochlor in plants compared with 10 d-aged BC. Biochar (BC) can alter the fate and bioavailability of pesticides in soil. In this study, the effects of three types of BCs (made of crofton weed, wood chips and rice hull) on the sorption of acetochlor, a common herbicide, were investigated. The acetochlor sorption constants (Kf value) were 309.96 μg1−nLn/kg (biochars made of ricehull, BCR), 3.54 μg1−nLn/kg (biochars made of crofton weed, BCH) and 2.27 μg1−nLn/kg (biochars made of wood chips, BCW). The persistence of acetochlor was 8 times greater when 1% BCR was added to the soil. Moreover, the half-life of acetochlor increased with increasing amounts of BC in the soil. The soil was amended with BCH (made of crofton weed) for two different aging period (10 d and 20 d) to evaluate the effects of aged BC on acetochlor accumulation in maize seedlings (Zea mays L). Amendment with 10 d-aged BCH in soil decreased the bioaccumulation of acetochlor. However, the concentrations and bioconcentration factors in maize cultivated in 20 d-aged BCH-amended soils were significantly higher than those in soil with no BCH amendments and with 10 d-aged BCH amendments. These results imply that BC aged in soil for a long period can increase the bioaccumulation of acetochlor in plants and the influences of BC on environmental risks of pesticides must be further clarified.
[en] Hydrothermal carbonization (HTC) was performed on homogenized food waste (FW) in a batch reactor at 200, 230, and 260 °C for 30 min. Solid product, called hydrochar, was characterized by means of ultimate analysis, proximate analysis, higher heating value (HHV), and ash content. On the other hand, liquid products were analyzed by inductively coupled plasma (ICP), total carbon, and pH. HHV of FW was increased from 25.1 to 33.1 MJ kg−1 by HTC. Ash content is less than 3% for hydrochars as well as the raw FW. Fixed carbon increased from 18.8 to 22.4% with the increase of HTC temperature. Fuel characteristics indicate hydrochar as a potential solid fuel and carbon storage. Therefore, a simplified simulation model was created for a continuous process that performs HTC of 1 t of FW per day. It was determined that HTC of food waste has potential to be a viable process for the production of solid fuel, primarily due to ease of drying product char.
[en] The techniques employed in this project have successfully demonstrated the feasibility of preparing sorbents that achieve greater than 99% H(sub 2)S removal at temperatures 480 C and that retain their activity over 50 cycles. Fundamental understanding of phenomena leading to chemical deactivation and high regeneration light-off temperature has enabled us to successfully prepare and scale up a FHR-32 sorbent that showed no loss in reactivity and capacity over 50 cycles. This sorbent removed H(sub 2)S below 80 ppmv and lighted-off nicely at 480 C during regeneration. Overall the test is a success with potential for an optimized FHR-32 to be a candidate for Sierra-Pacific. An advanced attrition resistant hot-gas desulfurization sorbent that can eliminate the problematic SO(sub 2) tail gas and yield elemental sulfur directly has been developed. Attrition resistant Zn-Fe sorbent (AHI-2) formulations have been prepared that can remove H(sub 2)S to below 20 ppmv from coal gas and can be regenerated using SO(sub 2) to produce elemental sulfur
[en] Gas, manufactured from coal or oil was used to light and heat homes, industries, and streets of this country from the mid-1800s to the late 1940s or early 1950s. The era, with its associated gas lights, faded with the development of natural gas supplies and direct use of other fossil fuels. Today, Manufactured Gas Plant (MGP) sites are part of our history. Most of the MGPs were operated at a time when the state of the environmental sciences was much less sophisticated and the environmental regulations were much less stringent or nonexistent. While there was an awareness of potential environmental problems then the concerns were more qualitative (e.g., odor, color) and resulted in minimal treatment of process residuals. Inasmuch as there may be over a thousand MGP sites in the United States, it also became clear that utility research institutes such as the Gas Research Institute (GRI) and the Electric Power Research Institute (EPRI) should address key research and management issues related to site investigation, risk assessment, and site remediation. Information gained from these research initiatives would serve the industry as a whole, as well as other groups involved in the assessment of MGP sites. This paper provides and overview of these programs and identifies how additional information can be obtained
[en] During this time period, at WVU, we tried several methods to eliminate problems related to condensation of heavier products when reduced Mo-Ni-K/C materials were used as catalysts. We then resumed our kinetic study on the reduced Mo-Ni-K/C catalysts. We have also obtained same preliminary results in our attempts to analyze quantitatively the temperature-programmed reduction (TPR) spectra for C-supported Mo-based catalysts. We have completed the kinetic study for the sulfided Co-K-MoS /C catalyst. We have compared the results of methanol synthesis 2 using the membrane reactor with those using a simple plug-flow reactor. At UCC, the complete characterization of selected catalysts has been completed. The results suggest that catalyst pretreatment under different reducing conditions yield different surface compositions and thus different catalytic reactivities