Science.gov (United States)

Homestake Ore from the Ambrosia Lake District of New Mexico was treated in the Alkaline Leach-- Filtration Pilot Plant at Grand Junction, Colorado. Detailed information on grinding, leaching, flltration, and precipitation in connection with the processing of this ore is given. Autoclave leaching and continuous yellow cake precipitation were employed. The circuit liquors contnined organic material that was detrimental to clariflcation and precipitation and the results show that ihe ore was amenable to the Alkaline Leach--Filtration process only if a special additive was used. (auth)

Energy Technology Data Exchange (ETDEWEB)

COGNIS TERRAMET{reg_sign} soil leaching and Bescorp soil washing systems have been successfully combined to remediate an ammunition test burn area at the Twin Cities Army Ammunition Plant (TCAAP), New Brighton, MN. This cleanup is the first in the country to combine these two technologies, and this approach offers a permanent remedial solution. In Fall 1993, 1,600 tons of soil were remediated with an additional 10,000+ tons treated in 1994. The cleaned soil remained on-site, and the heavy metal contaminants were removed, recovered, and recycled. Eight heavy metals were removed from the contaminated soil achieving the very stringent cleanup criteria of <175 ppm for residual lead and achieving background concentrations for seven other heavy metals (antimony, cadmium, chromium, copper, mercury, nickel, and silver). In addition, both live and spent ordnance had to be removed in the soil treatment plant to meet the cleanup ...

Energy Technology Data Exchange (ETDEWEB)

The combination of wood gasification and high temperature fuel cells like solid oxide fuel cells (SOFC) is an interesting approach to achieve high electrical efficiencies (40%) in small scale combined heat and power plants. This combination is called 'Biomass - Integrated Gasification Fuel Cell System' (B-IGFC). The main challenge is the adjustment of the three main components gasification, gas cleaning and fuel cell. In this technology, the first proof of principle by combining a gasifier with a SOFC in a laboratory scale for more than 100 hours was achieved. During this period, no deactivation of the system was found. (author)

International Nuclear Information System (INIS)

Different types of radioactive liquid waste are being generated at Advanced Fuel Fabrication Facility (AFFF), Tarapur during the quality control analysis of the mixed oxide (MOX) fuel pellets. A laboratory scale study was performed for treatment of such waste. Some of the waste streams originating from U and Pu analysis contain components like sulphate and phosphate which interfere during chemical precipitation of alpha activity from the waste. Various chemical co-precipitation experiments were conducted based on alkaline precipitation. Reductive precipitation using sodium sulphite and Fe(II) was found to be promising and the same was suggested for plant scale treatment. (author)

Energy Technology Data Exchange (ETDEWEB)

This report presents the results of an assessment of uranium in situ leach mining costs through the application of process engineering and discounted cash flow analysis procedures. A computerized costing technique was developed to facilitate rapid cost analyses. Applications of the cost model will generate mine life capital and operating costs as well as solve for economic production cost per pound U/sub 3/O/sub 8/. Conversely, rate of return may be determined subject to a known selling price. The data bases of the cost model were designed to reflect variations in Texas versus Wyoming site applications. The results of applying the model under numerous ore deposit, operating, well field, and extraction plant conditions for Texas and Wyoming are summarized in the report. Sensitivity analysis of changes in key project parameters have also been tested and are included.

Energy Technology Data Exchange (ETDEWEB)

Air pollution constraints continue to intensify, resulting in solid waste volume increases. An example of this is coal burning power plant flue gas desulfurization by scrubbing. The aqueous suspensions of calcium sulfate hemihydrate or calcium sulfate dihydrate will exceed 200 million tons annually by the year 2000. Disposal of these wastes can have massive environmental effects, due to physical instability and leaching to groundwater. One alternate disposal technique is sulfopozzolanic fixation, converting the FGD waste by addition of fine coal ash and an alkaline earth additive, into a monolithic mass. 6 refs., 17 figs., 3 tabs.

International Nuclear Information System (INIS)

One of the design targets for the ITER Tokamak Exhaust Processing system is not to lose more than 10"-"5 g h"-"1 into the Normal Vent Detritiation System of the Tritium Plant. The plasma exhaust gas, therefore, needs to be processed in a way that an overall tritium removal efficiency of about 10"8 is reached. Such a high decontamination factor can only be achieved by multistage processes. The third step of the three step CAPER process developed at the TLK is based on a so-called permeator catalyst (PERMCAT) reactor, a direct combination of a Pd/Ag permeation membrane and a catalyst bed. The PERMCAT principle is based on isotopic swamping in a counter current mode. Previous tritium experiments employing laboratory scale PERMCAT reactors have revealed decontamination factors as high as 10"5 for the third CAPER step. First tritium tests with a technical scale PERMCAT reactor led to similar decontamination factors and clearly ...

Energy Technology Data Exchange (ETDEWEB)

The Oak Ridge National Laboratory (ORNL) is developing a treatment process for remote-handled (RH) liquid transuranic mixed waste governed by the concept of minimizing the volume of waste requiring disposal. This task is to be accomplished by decontaminating the bulk components so the process effluent can be disposed with less risk and expense. Practical processes have been demonstrated on the laboratory scale for removing cesium 137 and strontium 90 isotopes from the waste, generating a concentrated waste volume, and rendering the bulk of the waste nearly radiation free for downstream processing. The process is projected to give decontamination factors of 10{sup 4} for cesium and 10{sup 3} for strontium. Because of the extent of decontamination, downstream processing will be contact handled. The transuranic, radioactive fraction of the mixed waste stream will be solidified using a thin-film evaporator and/or microwave solidification system. ...

UK PubMed Central (United Kingdom)

The purpose of the work was to quantitatively characterize temperature effects on the bacterial leaching of sulfide ore material containing several sulfide minerals. The leaching was tested at eight...Full Text Available

International Nuclear Information System (INIS)

The development of crud removal technology has started with the finding of the resin aging effect that an old ion exchange resin, aged by long year of use in the condensate demineralizer, had an enhanced crud removal capability. It was confirmed that some physical properties such as specific surface area and water retention capacity were increased due to degradation caused by long year of contact with active oxygens in the condensate water. So, it was speculated that those degradation in the resin matrix enhanced the adsorption of crud particulate onto the resin surface, hence the crud removal capability. Based on this, crud removal resin with greater surface area was first developed. This resin has shown an excellent crud removal efficiency in an actual power plant, and the crud iron concentration in the condensate effluent was drastically reduced by this application. However, the cross-linkage of the cation resin had to be lowered in a delicate manner for that ...

International Nuclear Information System (INIS)

The persistence and binding of the insecticide in soil and its residual effect in tomato plant were studied under green house conditions using "1"4 C -labelled chemical. When the insecticide was applied topically on tomato plant, its residues were detected in different plant parts; the amounts of which varied according to the mode of application and time of sampling. At the end of the experimental period (45 days) about 10% of the applied dose was recovered in the aerial parts of the plant following foliar application as compared with 2.4% recovery after soil application. Soil application of lindane led to higher residual content in the fruits than foliar application. The insecticide was also found to dissipate than to leach to lower soil horizons and was confined to the upper layers with no pronounced degradation capacity. Time to 50% disappearance (Dt_5_0 value) for lindane was ...

Energy Technology Data Exchange (ETDEWEB)

Short communication

Energy Technology Data Exchange (ETDEWEB)

In this paper, a concept of technology that can be helpful for lowering the negative influence of the synthetic (based on the Solvay process) soda ash plant on the natural environment is presented. We describe the desulphurisation of combustion gases from the factory's power plant, which is based on their absorption in the overflow of distiller waste. The excess of lime milk, which is added in the process of ammonia regeneration from filter liquor, results in a strong alkalinity of distiller waste. The high pH of distiller waste favours absorption of acidic combustion gases. The laboratory-scale tests showed about 80% efficiency of the desulphurisation process. The suspension samples we obtained consist mainly of CaCO{sub 3}. We suggest using the obtained solid phase as an adsorbent-insert in Fluidised Bed Combustion technology (FBC). Based on raw material prices, production costs, and average sell prices of the ...

Energy Technology Data Exchange (ETDEWEB)

Recent research at the laboratory scale by a number of organizations in different countries has shown that with the use of particular types of solvents it is possible to achieve almost complete conversion of coal to liquid products under relatively mild process conditions. This work is reviewed and the conclusions to be drawn from it are summarized.

Energy Technology Data Exchange (ETDEWEB)

This paper reports the results of leaching experiments conducted with and without Thiobacillus ferroxidans at the same conditions in solution. The extent of leaching of ZnS with Bacteria is significantly higher than that without bacteria at high concentrations of ferrous ions. A porous layer of elemental sulfur is present on the surfaces of the chemically leached particles, which no sulfur is present on the surfaces of the bacterially leached particles. The analysis of the data using the shrinking-core model shows that the chemical leaching of ZnS is limited by the diffusion of ferrous ions through the sulfur product layer at high concentrations of ferrous ions. The analysis of the data shows that diffusion through the product layer does not limit the rate of dissolution when bacteria are present. This suggests that the action of T.ferroxidans in oxidizing the sulfur formed on the ...

International Nuclear Information System (INIS)

An effective procedure for removing _3H, Xe and Kr from irradiated fuels was demonstrated using Shippingport UO"2 fuel. The release characteristics of _3H, Kr, Xe, and I from irradiated nuclear fuel have been determined as a function of temperature and gaseous environment. Vacuum outgassing and a flowing gas stream have been used to vary the gaseous environment. Vacuum outgassing released about 99% of the _3H and 20% of both Kr and Xe within a 3 h at 1500_0C. Similar results were obtained using a carrier gas of He containing 6% H"2. However, a carrier gas containing only He resulted in the release of approximately 80% of the _3H and 99% of both Kr and Xe. These results indicate that the release of these volatile fission products from irradiated nuclear fuel is a function of the chemical composition of the gaseous environment. The rate of tritium release increased with increasing temperature (1100 to 1500_0C) and with the addition of hydrogen to the gas stream. Using crushed UO"2 fuel ...

Energy Technology Data Exchange (ETDEWEB)

The oil shales of the Eastern United States represent a very large energy resource that also lies close to the marketplace. Although estimates vary, one estimate shows that more than 400 billion barrels of oil are recoverable from surface-mineable Devonian oil shales in the states of Alabama, Indiana, Kentucky, Michigan, Ohio, and Tennessee. Conventional thermal retorting of Eastern and Western oil shales with comparable organic carbon contents results in a much lower oil yield for the Eastern shales. This discouraged research and development of this energy resource, until about ten years ago, when the Institute of Gas Technology discovered that retorting Eastern oil shales in a hydrogen-rich atmosphere at elevated pressures gives oil yields that are 2.5 times those possible by thermal retorting. Over the last ten years many research, development, and feasibility programs, both Government- and industry-funded, have been conducted to utilize the Eastern oil shale resources. The scope of ...

International Nuclear Information System (INIS)

A preliminary investigation was conducted on ion specific membranes. This investigation concentrated on testing candidate organic compounds for transporting cesium ions through a membrane composed of the organic compound supported on a substrate. Solid PVC membranes were initially tried, but were found to be too slow. Thereafter, only liquid membranes were tested. These were faster and cesium concentration factors up to 2.96 were achieved in a single membrane cell. A cell with two membranes achieved a cesium concentration factor of 4.19. Cesium precipitation with sodium tetraphenyl borate in high sodium concentrations was explored. No interference from sodium was found until the sodium nitrite concentration reached 4.5 moles. Concurrently, cesium concentrations as high as 5.4 g/L were precipitated. Potassium tetraphenyl borate is being investigated for use in exchange columns for the removal of cesium from solutions. Initial investigations show that cesium removal is affected by [K"+] ...

Science.gov (United States)

A number of agricultural and engineering uses for fixated flue gas desulfurization (FGD) material exist; however, the potential for leaching of hazardous elements has limited widespread application and the processes controlling the leaching of this material are poorly understood. In this study, a flow-through rotating-disk system was applied to elucidate the relative importance of bulk diffusion, pore diffusion, and surface chemical reaction in controlling the leaching of fixated FGD material under pH conditions ranging from 2.2 to 6.8. Changing the hydrodynamics in the rotating disk system did not affect the leaching kinetics at both pH 2.2 and 6.8, indicating that bulk diffusion was not the kinetic-limiting step. Application of the shrinking core model (SCM) to the data suggested a surface reaction-controlled mechanism, rather than a pore diffusion mechanism. The leaching of ...

International Nuclear Information System (INIS)

One set of hypotheses offered to explain the decline of red spruce (Picea rubens Sarg.) in eastern North America focuses on the effect of acidic deposition on soil chemistry changes that may affect nutrient availability and root function. Long-term soils data suggests that soil acidification has occurred in some spruce stands over the past 50 yr, with plant uptake and cation leaching both contributing to the loss of cations. Studies of tree ring chemistry also have indicated changes in Ca/Al and Mg/Al ratios in red spruce wood, suggesting increases in the ionic strength of soil solution. Irrigation studies using strong acid inputs have demonstrated accelerated displacement of base cations from upper horizons. Spruce-fir (Abies spp.) nutrient budgets indicate that current net Ca and Mg leaching loss rates are of the same order of magnitude as losses to whole tree harvest removals, spread out over a 50-yr rotation. For most ...

Energy Technology Data Exchange (ETDEWEB)

The leached glass is subject to leachant attack and results in surface layer alteration which greatly affects the corrosion progress of glass forms. This work studied the composition change, precipitation, pitting corrosion as well as surface layer break and spallation of the leached glass forms. 6 conclusions can be made: 1. The extent of surface layer alteration is related to many factors such as temperature, pH, leachant chemistry, flow rate and leach duration, etc. 2. The alkali element Na is seriously depleted and the elements like U.Ti,Fe, Ca and Mg are enriched in the surface layer. The influence of media has such order: Fe{sub 2}O{sub 3} > Na-bentonite > Zeolite. 3. The precipitate formed in leach test for 56 days at 90 {infinity}C is mostly amorphous, but after 91 days has crystallized. There is K - Ca - Al - Si crystal,the amount of Al, K and Si is increasing, but the amount of ...

Energy Technology Data Exchange (ETDEWEB)

Energy from biomass is a CO{sub 2} neutral, sustainable form of energy. Anaerobic digestion is an established technology for converting biomass to biogas, which contains around 60% methane, besides CO{sub 2} and various contaminants. Most types of biomass contain material that cannot be digested; in woody biomass, this portion is particularly high. Therefore, conventional anaerobic digestion is not suited for the production of biogas from woody biomass. While wood is already being converted to energy by conventional thermal methods (gasification with subsequent methanation), dung, manure, and sewage sludge represent types of biomass whose energy potential remains largely untapped (present energetic use of manure in Switzerland: 0.4%). Conventional gas phase processes suffer from a low efficiency due to the high water content of the feed (enthalpy of vaporization). An alternative technology is the hydrothermal gasification: the water contained within the biomass serves as reaction ...

International Nuclear Information System (INIS)

The uptake of "9"9Tc by trees intercepting contaminated groundwater from a radioactive waste storage site was measured to identify the major "9"9Tc pools within the woodland ecosystem and to assess the relative mobility of "9"9Tc in the existing element cycle. The highest average "9"9Tc concentrations in vegetation were found in herbaceous plants. Tree wood was the major above-ground pool for "9"9Tc because of the high concentrations in wood as well as the large amount of wood relative to other biomass at the site. Technetium was not easily leached from the trees by rainfall and was not readily extractable from forest floor leaf litter by water. The relative importance of return pathways for "9"9Tc to the forest floor was leaf fall > stemflow > throughfall, indicating that "9"9Tc was conserved by the trees. Snails and millipedes from the leaf litter layer concentrated technetium 20- and 16-fold, respectively, above levels found in the ...

Energy Technology Data Exchange (ETDEWEB)

A residue of the sugar industry can be used in revegetation programs on metal contaminated sites. - Phytostabilisation of bare heavily contaminated substrate, such as abandoned mine sites, is considered a very appropriate technology in order to diminish erosion and dispersion of contaminants into the surroundings. In this short-term pot study, application of industrial sugar residue (ISR), a waste product of the sugar industry, proved to ameliorate spoils conditions for plant performance by elevating pH and immobilising several metals. Although arsenate concentrations were positively correlated to spoil pH and spoil treatment with ISR mobilised As, growth of both Phaseolus vulgaris and Holcus lanatus improved significantly after applications of 3.75 g ISR kg{sup -1} dry spoil. Nutrient uptake from the substrate, with the exception of potassium, was elevated by ISR. As a remediation technique ISR application could be effective although in As-contaminated sites ...

Energy Technology Data Exchange (ETDEWEB)

Co-combustion of chicken litter with coal was performed in a laboratory-scale fluidized bed combustor to investigate the effect of chicken litter addition on the partitioning behavior of mercury. Gaseous total and elemental mercury concentrations in the flue gas were measured online, and ash was analyzed for particle-bound mercury along with other elemental and surface properties. The mercury mass balance was between 85 and 105%. The experimental results show that co-combustion of chicken litter decreases the amount of elemental and total mercury in the gas phase. Mercury content in fly ash increases with an increasing chicken litter share. 22 refs., 6 figs., 5 tabs.

International Nuclear Information System (INIS)

Leachability of neutron irradiated fly ash is investigated as a method for studying element leaching properties of this material with various leaching media. Quantitative aspects of radiation damage are shown to be minor. Therefore, the technique should be applicable for this purpose. It is further shown that this technique affords significant advantages over the conventional post-leaching analysis with respect to utilization of natural solutions for the investigation of fly ash leachability. However, for a few elements such as Pb, Bi, V, and Al, the various nuclear parameters involved invalidate applicability of the present technique.

Energy Technology Data Exchange (ETDEWEB)

In studying the absorption of carbon dioxide by absorbents impregnated with alkanol amines, researchers used a laboratory-scale packed column to determine the overall gas-phase mass-transfer coefficients and enhancement factors. A model derived for the mechanism of the chemical reaction taking place in the interfacial layer accounts for the effect of the reaction upon the absorption rate better than other models.

British Library Electronic Table of Contents (United Kingdom)

The factors affecting the rate of silica leaching in alkaline aqueous media from surface silanized, nanoporous, amorphous, silica gels and from silanized silica gels that have been modified with polyamines to form the previously reported silica polyamine composites (SPCs), BP-1 and BP-2 have been investigated. Silanization with alkyl trichlorosilanes slows the rate of silica leaching relative to the unmodified silica gels. The use of bulkier aryl silanes somewhat decreases the silica leaching under the same conditions. Interestingly, after modification of the silanized silica with poly(allylamine) (PAA) to make BP-1, the leaching increases, but subsequent modification of the SPC with chloroacetic acid to make BP-2, quenches this increase. A mechanism explaining these results is discussed. ...

International Nuclear Information System (INIS)

This study presents a rapid and selective method for the recovery of lanthanides and yttrium, existing in economically interesting concentrations, from red mud, the byproduct of the alumina production. The leaching process is based on the extraction of these elements with diluted nitric acid from red mud under moderate conditions and without using any preliminary treatment. Several parameters such as leaching agents, contact time, temperature, pressure and solid to liquid ratio were investigated in order to achieve an optimum recovery. The process followed here was selected taking into account its efficiency for the selective recovery of yttrium and lanthanides, but also its suitability for the subsequent liquid-liquid extraction of the leaching solution for the separation of the individual lanthanides. The achieved recovery percentages were for Y about 90%, for the investigated heavy lanthanides (Dy, Er, Yb) up to 70%, for ...

International Nuclear Information System (INIS)

Model construction of the laboratory scale superconducting fault current limiter circuit (SFCL) has been performed. The SFCL is fault current limiter and used as electric network security. It mainly consists of a copper coil, a superconducting ring and an iron core that are concentrically arranged. The SFCL circuit is essentially a transformer where the secondary windings are being replaced by the ring of YBa_2Cu_3O_7_-_x superconductor (HTS). The ring has critical transition temperature Tc = 92 K and critical current Ic = 3.61 A. Characterization of the SFCL circuit is simulated by ANSYS version 5.4 software. The SFCL circuit consists of load and transformer impedances. The results show that the inductions of magnet field flux in the iron core of primer windings and ring disappear to one other before fault state. It means that impedance of the transformer is zero. After the condition a superconductivity behavior of the ring is disappear so ...

British Library Electronic Table of Contents (United Kingdom)

Abstract First results showing the viability of combining laser chemical processing (LCP) and aerosol jet printing (AJP) technologies to produce a high-efficiency front side for silicon solar cells are presented. LCP simultaneously opens the anti-reflection coating (ARC) and highly dopes the underlying silicon to create a selective emitter, while AJP is the first in a two-step fine-line contact formation procedure. The electrical properties as well as the morphology of the resulting structures are presented. Performance similar to that achieved with evaporated TiPdAg metallization is demonstrated. Copyright 2010 John Wiley & Sons, Ltd.

Energy Technology Data Exchange (ETDEWEB)

Separation of the bulk soluble chemical salts from the insoluble metal hydroxides and radionuclides is central to the strategy of disposing Hanford tank waste. Sludge washing and caustic leaching have been selected as the primary methods for processing the 230 million L (61,000,000 gal) of Hanford tank waste. These processes are very similar to those selected for processing waste at the West Valley Site in New York and the Savannah River Site in South Carolina. The purpose of sludge washing is to dissolve and remove the soluble salts in the waste. Leaching of the insoluble solids with caustic will be used to dissolve aluminum hydroxide and chromium hydroxide, and convert insoluble bismuth phosphate to soluble phosphate. The waste will be separated into a high-level solids fraction and a liquid fraction that can be disposed of as low-level waste after cesium removal. The washing and leaching operations involve batchwise ...

Energy Technology Data Exchange (ETDEWEB)

Cereal straw, a by-product in the production of agricultural crops, is considered as a potentially large source of energy supply with an estimated value of 47 x 10{sup 18} J worldwide. However, there is some debate regarding the actual amounts of straw which could be removed from arable soils without jeopardizing their quality, as well as the potential trade-offs in the overall straw-to-energy chain compared to the use of fossil energy sources. Here, we used a deterministic model of C and N dynamics in soil-crop systems to simulate the effect of straw removal under various sets of soil, climate and crop management conditions in northeastern France. Model results in terms of nitrate leaching, soil C variations, nitrous oxide and ammonia emissions were subsequently inputted into the life-cycle assessment (LCA) of a particular bio-energy chain in which straw was used to generate heat and power in a plant producing bio-ethanol from wheat grains. ...

Energy Technology Data Exchange (ETDEWEB)

The composition of alkaline and neutral boric acid containing evaporator concentrates resulting from the treatment of radioactive waste water in nuclear power plants with WWER reactors is described as well as the processing of these concentrates to a product suitable for final disposal. Tests with mock solutions of these evaporator concentrates have been performed at the laboratory and teststand scale to produce a dry residue by continuous thickening, which can be processed into a highly leach resistant product, suitable for final disposal, by cementation. Ca-compounds must be added to the evaporator concentrates prior to the drying in an rotary thin-film evaporator (RTFE). The tests showed that neutral evaporator concentrates can be dried in a RTFE with addition of small amounts of Ca-compounds. The alkaline evaporator concentrates with high boric acid and total salt load require a multiple amount of Ca-compounds and diluting water to perform ...

Energy Technology Data Exchange (ETDEWEB)

The Clean Water Act of 1977 directed EPA to establish standards for use and disposal of sewage sludge (biosolids). The application of biosolids to non-agricultural lands is becoming increasingly important as a method of waste disposal. Ecological endpoints at the population, community, and/or ecosystem level have not previously been emphasized in the development of regulatory standards for municipal sewage sludge. This risk assessment focuses on terrestrial endpoints in four ecosystem types to which substantial quantities of sludge have been applied or are expected to be applied in the future: northwest Douglas-fir forest, southeastern loblolly pine plantation, eastern deciduous forest, and semi-arid rangeland. Conceptual models suitable for all ecosystems were developed that depict the links among assessment endpoints. Estimates of risks to wildlife from contaminants and simulations of impacts of nitrogen in sewage sludge on the structure and function of forest communities are ...

International Nuclear Information System (INIS)

Arsenic was predominantly present as inorganic arsenite in the fronds of the hyperaccumulator Chinese brake. - Arsenic speciation is important not only for understanding the mechanisms of arsenic accumulation and detoxification by hyperaccumulators, but also for designing disposal options of arsenic-rich biomass. The primary objective of this research was to understand the speciation and leachability of arsenic in the fronds of Chinese brake (Pteris vittata L.), an arsenic hyperaccumulator, with an emphasis on the implications for arsenic-rich biomass disposal. Chinese brake was grown for 18 weeks in a soil spiked with 50 mg As kg"-"1 as arsenate (AsO_4"3"-), arsenite (AsO_3"3"-), dimethylarsinic acid (DMA), or methylarsonic acid (MMA). Plant samples were extracted with methanol/water (1:1) and arsenic speciation was performed using high performance liquid chromatography coupled with atomic fluorescence spectrometry. The impacts of air-drying on arsenic species and ...

Energy Technology Data Exchange (ETDEWEB)

Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily at a reasonable cost. A primary example of this is copper heap leaching, where there are no binders currently encountered in this acidic environment process. As a result, operators of many facilities see a large loss of process ...

Science.gov (United States)

The results of studies on: (1) development of suitable glass compositions for solidification and vitrification of high level radioactive wastes, and (2) the characteristics of these compositions, namely, leaching, mechanical properties, thermal conductivity, viscosity and homogeneity evaluation are reported. Inactive simulated purex waste was used for compositions reported herein. The data generated on leaching and other product characteristics of the selected vitrified waste products was used to evaluate the performance of corresponding experimental units and techniques with respect to their reproducibility and reliability.

International Nuclear Information System (INIS)

The reactor fuel cycle based on uranium is described. The various stages in the cycle include mining of uranium ores followed by crushing and grinding, leaching and purification of leach liquor by ion exchange resin process or solvent extraction process, refining of uranium concentrate (yellow cake) by digesting with HNO_3 and then solvent extracting uranyl nitrate with TBP, conversion of uranyl nitrate to uranium hexafluoride, production of uranium metal, uranium enrichment, fabrication of reactor fuel elements and reprocessing of the spent fuel. Chemical reactions wherever they are involved are explained. (M.G.B.).

International Nuclear Information System (INIS)

The bituminzation of decontamination and ion exchange resin stripping wastes with four grades of asphalt was investigated to determine the effects of asphalt type on the properties of the final products. All waste forms deformed readily under light loads indicating they would flow if not restrained. It was observed in all cases that product leaching rates increased as the hardness of the asphalt used to treat the waste increased. If bituminization is adopted for any Ontario Hydro aqueous radioactive wastes they should be treated with soft asphalt to obtain optimum leaching resistance and mechanical stability during interim storage should be provided by a corrosion resistant container.

International Nuclear Information System (INIS)

Spent nuclear wastes are inevitable issues to use nuclear power as a sustainable energy. Therefore, every country has their fuel cycles which are best for their environmental and/or political circumstances for the use of nuclear energy. These days agreements are made that spent nuclear fuels should be recycled to minimize waste volume and its toxicity all around the world. Republic of Korea also has a plan to recycle the spent nuclear fuels by using Gen-IV concept burner reactors and pyro-process plants. Not many options of national nuclear strategies are exist because Korea has too many people for its limited land space. KAERI already has been proposing a national fuel cycle concept called 'KIEP-21' that encompasses all the requirements of the advanced nuclear fuel cycle such as reduction of volume, toxicity, HLW heat load and so on. Authors suggest non-national fuel cycle concept called 'PyroGreen' for the sustainable nuclear energy system. PyroGreen is also ...

British Library Electronic Table of Contents (United Kingdom)

The fossil fuel consumption and pollutant emissions in a coal fired fluidized bed boiler could be reduced by biomass pyrolysis gas reburning. The influence of three kinds of biomass pyrolysis gases on the emission of N2O in a laboratory scale fluidized bed was investigated using the mechanism of GRI3.0 in this paper. The results showed that: the effect of sawdust pyrolysis gas reburning on N2O was more significant than that of rice husk and orange peel under the same conditions; the increase of initial oxygen content from 1% to 8% in flue gas would restrain the decomposition of N2O; the N2O decomposition was enhanced by increasing reaction temperature from 1073.15 K to 1323.15 K, and the decomposition rate may reach 99% at 1223.15 K.

Energy Technology Data Exchange (ETDEWEB)

Studies of CWF preparation at laboratory scale have been carried out using the type and amount of additives and coal content as process variables. Other factors such as particle size, time and rate of stirring were kept constant. CWF with 45 wt% of dry solids, heating value of 5,475 BTU/lb, and stable without the evidence of sedimentation for 9 weeks have been obtained using carboxy methyl cellulose (CMC) as the additive. Low coal content and low heating value can be increased by hydrothermal process on the elevated temperature and pressure. By this process, CWF with dry solid of 55 wt% and a heating value of 7,125 BTU/lb could be obtained. 6 refs., 8 figs., 2 tabs.

Energy Technology Data Exchange (ETDEWEB)

This paper reported on a study in which rapeseeds were separated into high quality seed for food oil and low quality seed for biofuels. A laboratory-scale oilseed screw press was then used to examine the effects of choke opening and seed preheating on the rapeseed pressing performance and the quality of food oil and biofuels oil. Oil recovery and chlorophyll content was found to increase as maximum pressure increased. In terms of pressing performance, the rapeseed heated by microwaves yielded more oil and chlorophyll than without heating. The NEB ratio of microwave heating press with an 8.0 mm choke opening was advantageous. Rapeseed oil extracted from low quality seeds was found to have a high acid value. The quality of oil extracted by oilseed screw press was found to be good and met the requirements of the Codex Alimentarius for edible oils.

British Library Electronic Table of Contents (United Kingdom)

This paper deals with surface defects of automobile outer panels, which alter significantly the vehicle quality. Such defects occur during springback, after forming or flanging steps, and are characterized by concave depression of small amplitude over the convex shape of the part. The aim of this work is to reproduce at the laboratory scale a surface defect that occurs after flanging on a geometry similar to a door upper corner. A dedicated device has been designed in order to generate small size surface defects during flanging of metallic thin sheets. The outer surface of the sample was digitalized and the spatial geometry of the defect was evaluated from curvature change along 2D profiles. This study shows that the flanging height does not influence significantly the surface defect geome...

Energy Technology Data Exchange (ETDEWEB)

This report describes the development of solidification systems for sodium nitrate waste. Sodium nitrate waste was solidified in the polymers polyethylene, polyester-styrene (PES), and water-extendible polyester-styrene (WEP). Evaluations were made of the properties of waste forms containing various amounts of sodium nitrate by leaching immersion in water, measuring compressive strengths and by the EPA Extraction Procedure. Results of the leaching test are presented as cumulative fraction leached (CFL), incremental leaching rate, and average leaching indices (LI). For waste forms containing 30 to 70 wt% sodium nitrate, the CFL ranged from 9.0 x 10/sup -3/ to 7.3 x 10/sup -1/ and the LI from 11 to 7.8. After ninety days immersion in water, the compressive strengths ranged from 720 psi to 2550 psi. The nitrate releases from these samples using the EPA Extraction Procedure were below ...

British Library Electronic Table of Contents (United Kingdom)

A study of the effect of a clayey soil modified in situ and ex situ with the cationic surfactant octadecyltrimethylammonium bromide (ODTMA), on the retention of linuron, atrazine and metalaxyl was carried out. Leaching of these compounds was studied in columns of a natural clayey soil and the same clayey soil modified by direct injection of the surfactant in situ, and in columns of a natural sandy soil and the same sandy soil modified by intercalation of a barrier of the clayey soil saturated ex situ with the surfactant. Breakthrough curves indicated the total immobilization of linuron in modified soils and a decrease in the leaching kinetics of atrazine and metalaxyl compared to what was obtained in the natural soil. The results indicate the use of the clayey soil modified in situ or ex s...

British Library Electronic Table of Contents (United Kingdom)

Leptospirillum ferriphilum and Acidithiobacillus caldus are two important acidophilic microorganisms involved in iron and sulfur oxidation during bioleaching. Cell adsorption to mineral surfaces is important for the direct leaching or contact leaching of minerals. In this study, we report the competitive adsorption of binary mixtures of L. ferriphilum LF-104 and A. caldus MTH-04 onto pyrite surfaces. The Langmuir adsorption parameter (CAm) indicated that these two bacteria underwent competitive adsorption to pyrite. Real-time quantitive PCR was used to quantify the relative amounts of L. ferriphilum and A. caldus adsorbed onto the surfaces of pyrite following exposure to a mixture of these two organisms. The adsorption of L. ferriphilum was not affected by A. caldus. However, adsorption of...

Energy Technology Data Exchange (ETDEWEB)

Finland has some 10 million hectares of peatland, accounting for almost a third of its total area. Macroclimatic conditions have varied in the course of the Holocene growth and development of this peatland, and with them the habitats of the peat-forming plants. Temperatures and moisture conditions have played a significant role in determining the dominant species of mire plants growing there at any particular time, the resulting mire types and the accumulation and deposition of plant remains to form the peat. While in a natural state the mires of Finland have functioned as carbon dioxide sinks throughout the post-glacial period, but the ditching of peatland for forestry and agriculture, amounting to some 5,7 million hectares in Finland, has affected their water balance, especially over the last hundred years, and has thereby altered the quantity and species composition of the mire vegetation. The invasion of trees and woody ...

Energy Technology Data Exchange (ETDEWEB)

Molybdenum is separated from molybdenum-containing activated charcoal or char also containing small amounts of uranium obtained as a by-product in uranium leaching processes by stripping with an alkaline solution to provide a molybdenum containing solution containing substantially less than 500 ppm u/sup 3/o/sup 8/.

International Nuclear Information System (INIS)

To the crushed ore leaching is applied. The resulting solid-liquid mixture is fed to a hydro-cyclon grading facility; here the superfine grain is separated before the concentrated mixture can be filtered or centrifuged. The grading is done in several steps. From the liquid, ultimately ridded of the solid, uranium compounds are precipitated and the yellow cake is obtained. (DG).

Science.gov (United States)

The report gives results of a study of sintering and leaching mechanisms of fly ash/spent sodium sorbent mixtures from a dry injection flue gas desulfurization (FGD) process. It includes an estimate of the economics of pelletizing and sintering to handle the fly ash and spent sor...

British Library Electronic Table of Contents (United Kingdom)

Solid-state fermentation of soybean hulls supplemented with wheat bran using a co-culture of Trichoderma reesei and Aspergillus oryzae was performed. Three parameters - initial moisture content, incubation temperature, and initial pH - were optimized in culture flasks using response surface methodology. Parameter optimization was carried out with respect to filter paper activity and b-glucosidase activity in the culture. Temperature of 30^oC, pH of 5, and moisture content of 70% were found to be optimum. Optimized parameters were used for laboratory scale-up in static tray fermenters. The maximum filter paper activity of 10.7FPU/g-ds and b-glucosidase of 10.7IU/g-ds were obtained after 96-h incubation period in static tray fermenters in agreement with optimized activities at shake flask le...

Energy Technology Data Exchange (ETDEWEB)

Three inclined tubular digesters of 13- to 15-litre volume were operated at temperatures between 20 and 30 degrees C with hydraulic retention times of 10-15 days on pig slurry of 10%, 5% and 2.5% Total Solids content. Tube inclination of 16-20 degrees gave no scumming problems. Solids were retained, giving improved gas yields when compared with literature values for conventional stirred digesters. Solids retention is affected by the size of the digester exit and appears to be greater with slurry of low solids content. There is a link between the movement of solids and gas along, and out of, the digester which can lead to unstable oscillating gas production. Tracer studies showed soluble components of the slurry mixed throughout the whole volume of the digester in 25% of the hydraulic retention time or less. Solids moved in well dispersed plug flow. Gas production (both intrinsic and after the addition of acetate) was most rapid in the central section of the digester. Extra-cellular ...

International Nuclear Information System (INIS)

The rates of hydrogen release from simulated high-level liquid waste (SHLLW) during irradiation of "6"0Co #gamma#-rays have been studied using a laboratory-scale apparatus. The SHLLW used was made up of 28 different metal elements, the concentrations of which were determined from a computed data (ORIGEN-2) for a Purex spent fuel (burn-up of 4.5 GWd/t, cooling time of 4 years) except for those of corrosion products (Fe, Cr and Ni) and of chemical process additive (P). The nitrate ion concentration of the SHLLW was 4.97 M. The G-value of hydrogen release was 0.0164 for stirred conditions, but for nonstirred conditions with dose rate : 2.8 kGy/h and with the SHLLW solution height more than 8 cm, the following relation was found between the G-value and the solution height (d cm); G(H_2) = 0.100 d"-"1"."6. The G-values of oxygen and nitrogen releases were also determined. (author).

Energy Technology Data Exchange (ETDEWEB)

This report is to present the progress made on the project ''Establishment of an Environmental Control Technology Laboratory (ECTL) with a Circulating Fluidized-Bed Combustion (CFBC) System'' during the period January 1, 2005 through March 31, 2005. The following tasks have been completed. First, the renovation of the new Combustion Laboratory is nearly complete, and the construction of the Circulating Fluidized-Bed (CFB) Combustor Building is in the final stages. Second, the fabrication and manufacture of the CFBC Facility is being discussed with a potential contractor. Discussions with potential contactor regarding the availability of materials and current machining capabilities have resulted in the modification of the original designs. The selection of the fabrication contractor for the CFBC Facility is expected during the next quarter. Third, co-firing experiments conducted with coal and chicken waste have been initiated in the ...

Energy Technology Data Exchange (ETDEWEB)

Chemical-looping combustion is a promising technology for the combustion of gas or solid fuel with efficient use of energy and inherent separation of CO{sub 2}. Chemical-looping combustion of methane with calcium sulfate as a novel oxygen carrier was conducted in a laboratory scale fixed bed reactor. The effects of reaction temperature, gas flow rate, sample mass, and particle size on reduction reactions were investigated and an optimum operating condition was determined. The results show that this novel oxygen carrier has a high reduction reactivity and stability in a long-time reduction/oxidation test. The conversions of CH{sub 4} increased with a higher temperature, smaller gas flow rate, larger sample mass and smaller particle size. The suitable reaction temperature seems to be around 950 deg. C. Low temperatures lead to a low CH{sub 4} conversion, but a significant SO{sub 2} formation was observed at a higher temperature. The release of ...

International Nuclear Information System (INIS)

Ferritic/martensitic steel, modified 9Cr-1Mo steels have been used most extensively in the power generation industry throughout the world due to having superior high temperature properties such as high strength, creep resistance, and good microstructure stability. These steels are also the primary candidate for the RPVs(Reactor Pressure Vessels) of High Temperature Gas-Cooled Reactors. Currently, many studies has been conducted in laboratory-scale for mod. 9Cr-1Mo steels. However, there is a lack of the study on forged thick- section for RPVs. The differences in characteristics including the through thickness microstructure and mechanical properties between internal and external locations may occur during cooling after austenitization, because the thickness of RPVs is over about 200mm. Therefore, in order to use ferritic/martensitic steel as RPVs, a detailed assessment of the through thickness properties is needed. The purpose of this study is to investigate the ...

Energy Technology Data Exchange (ETDEWEB)

This study aims to develop a particulate model combining solid waste particle combustion and heavy metal vaporization from burning particles during MSW incineration in a fluidized bed. The original approach for this model combines an asymptotic combustion model for the carbonaceous solid combustion and a shrinking core model to describe the heavy metal vaporization. A parametric study is presented. The global metal vaporization process is strongly influenced by temperature. Internal mass transfer controls the metal vaporization rate at low temperatures. At high temperatures, the chemical reactions associated with particle combustion control the metal vaporization rate. A comparison between the simulation results and experimental data obtained with a laboratory-scale fluid bed incinerator and Cd-spiked particles shows that the heavy metal vaporization is correctly predicted by the model. The predictions are better at higher temperatures because of the temperature ...

Energy Technology Data Exchange (ETDEWEB)

When biomass is used as fuel for thermal conversion plants, minerals from the fuel can be responsible for major problems. Generally, these problems are associated with the existence and development of low melting compounds or eutectics, which form sticky layers. In a fluidised bed, this can result in bed-agglomeration and defluidisation. This causes local high temperature, which often accelerates the process. It ultimately can lead to a completely sintered bed content with a glassy phase gluing the bed particles together and shut-down of the plant. The main objective of the title project is to develop a methodology to predict ash/bed agglomeration and sintering problems, to indicate related problems and, furthermore, to identify solution methods to make different types of biomass streams more viable for energy production. Within the present study, selected fuels are subjected to different existing methods together with some new ones, in order ...

Energy Technology Data Exchange (ETDEWEB)

Acid mine drainage is a serious environmental problem caused by the oxidation of sulfide minerals that releases highly acidic, sulfate, and metals-rich drainage. In this study, alkaline industrial wastes were mixed with acid mine tailings in order to obtain neutral conditions. A series of column leaching tests were performed to evaluate the behavior of reactive mine tailings amended with alkaline-additions under dynamic conditions. Column tests were conducted of oxidized mine tailings combined with cement kiln dust, red mud bauxite, and mixtures of cement kiln dust with red mud bauxite. The pH results show the addition of 10% of alkaline materials permits the maintenance of near neutral conditions. In the presence of 10% alkaline material, the concentration of toxic metals such as Al, Cu, Fe, Zn are significantly reduced as well as the number of viable cells (Thiobacillus ferrooxidans) compared to control samples.

International Nuclear Information System (INIS)

A pretreatment flowsheet was tested for separating key radionuclide components from the sludge stored in one of the high level waste tanks (B-110) at the Hanford Site; this sludge resulted primarily from the bismuth phosphate process, which was one of the three major plutonium separation processes used at Handford. This test involved (1) washing with water, (2) caustic leaching, (3) acid dissolution, (4) separation of transuranic elements (TRUs) by extraction with octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide(CMPO), (5) separation of Sr by extraction with di-t-butylcyclohexano-18-crown-6, (6) separation of Cs from the acid-dissolved sludge solution by treatment with ammonium molybdophosphate (AMP), and (7) separation of Cs from the sludge wash and caustic leach solutions by ion exchange using a phenol-formaldehyde resin (CS-100). The results of the radionuclide separation steps indicated that the proposed flowsheet is a viable ...

Science.gov (United States)

Title list.

International Nuclear Information System (INIS)

Recovery of uranium by ion-exchange processes from impure acid leach liquors is described, which produce a concentrated and pure eluate employing 10% sulphuric acid elution. In situations where resin is loaded to 45 g/ltr or more the acid consumption at ambient temperature is less than 4 kg of H_2SO_4 per kilogram of U_3O_8. Precipitation with an alkali such as ammonia or magnesia produces a yellow cake of high purity. (author).

International Nuclear Information System (INIS)

In the early 1980s, AECL built a Waste Treatment Centre (WTC) for managing low-level solid and aqueous liquid wastes for converting CANDU wastes. At present, two liquid waste streams are being treated at the WTC. The liquid waste streams are volume-reduced by a combination of continuous crossflow microfiltration (MF), spiral wound reverse osmosis (SWRO) and tubular reverse osmosis (TRO) membrane technologies. The concentrate produced from the TRO system and the volume-reduced MF backwash solutions are evaporated while simultaneously adding bitumen in a thin-film evaporator. A water-free product of chemical and radiochemical salts and bitumen is removed in 200-L galvanized steel drums for storage. The radiation field of product drums on contact typically has a value of 0.5 to 3 R/h depending upon the feed concentration of radioactivity to the evaporator. The total solids content in the 200-L drum ranges from 25 to 35%. Encapsulated in the bitumen matrix are a variety of nonradiochemical ...

Energy Technology Data Exchange (ETDEWEB)

This is a collection of photographs of the plant which is now almost completed.

Science.gov (United States)

... qualified manufacturing employees. David Lichtinger, plant manager for Lord Corporation's aerospace products plant in ...

CERN Document Server

Applied and fundamental aspects of plant cell, tissue, and organ culture

UK PubMed Central (United Kingdom)

BackgroundSenescence is integral to the flowering plant life-cycle. Senescence-like processes occur also in non-angiosperm land plants, algae and photosynthetic prokaryotes. Increasing...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

This is the first time that the adsorption of binary mixtures of polycyclic aromatic hydrocarbons (PAHs) has been studied. This study was carried out at laboratory scale in an experimental apparatus specially designed for this aim: with gas-phase fluorescence, a new detection procedure was used. Experimental conditions, mainly in terms of temperature (150C) and contaminant concentration (approximately 1 ppmv), close to the ones observed in energy generation systems, were applied. The PAH adsorption process interpretation was carried out by recording the experimentally obtained breakthrough curves. After the detection parameter optimization, the influence of adsorbate characteristics in the hot gas cleaning of PAH was studied. In this system, the adsorption of 10 binary mixtures of five PAH (naphthalene (Np), fluorene (Fu), phenanthrene (Phe), fluoranthene (Fl), and pyrene (Py)) on an activated carbon was investigated. It was found that the ...

Energy Technology Data Exchange (ETDEWEB)

Three reactive materials were evaluated at laboratory scale to identify the optimum treatment reagent for use in a Permeable Reactive Barrier Treatment System at Rocky Flats Environmental Technology Site (RFETS). The contaminants of concern (COCS) are uranium, TCE, PCE, carbon tetrachloride, americium, and vinyl chloride. The three reactive media evaluated included high carbon steel iron filings, an iron-silica alloy in the form of a foam aggregate, and a peculiar humic acid based sorbent (Humasorb from Arctech) mixed with sand. Each material was tested in the laboratory at column scale using simulated site water. All three materials showed promise for the 903 Mound Site however, the iron filings were determined to be the least expensive media. In order to validate the laboratory results, the iron filings were further tested at a pilot scale (field columns) using actual site water. Pilot test results were similar to laboratory results; ...

Energy Technology Data Exchange (ETDEWEB)

Plans for the disposal of radioactive liquid and solid wastes presently stored in double-shell tanks at the Hanford Site call for retrieval and processing of the waste to create forms suitable for permanent disposal. Waste will be retrieved from a tank using a submerged slurry pump in conjunction with one or more rotating slurry jet mixer pumps. Pacific Northwest Laboratory (PNL) has conducted tests using simulated waste slurries to assess the effects of a impinging slurry jet on the corrosion rate of the tank wall and floor, an action that could potentially compromise the tank`s structural integrity. Corrosion processes were investigated on a laboratory scale with a simulated neutralized cladding removal waste (NCRW) slurry and in a subsequent test with simulated neutralized current acid waste (NCAW) slurry. The test slurries simulated the actual NCRW and NCAW both chemically and physically. The tests simulated those conditions expected to ...

Energy Technology Data Exchange (ETDEWEB)

In order to produce a quality grout from LLW using hydraulic cements, proper conditioning of the waste is essential for complete cement curing. Several technologies were investigated as options for conditions. Since the LLW is dilute, removal of all, or most, of the water will significantly reduce the final waste volume. Neutralization of the LLW is also desirable since acidic liquids to not allow cement to cure properly. The nitrate compounds are very soluble and easily leached from solid waste forms; therefore, denitration is desirable. Thermal and chemical denitration technologies have the advantages of water removal, neutralization, and denitration. The inclusion of additives during thermal treatment were investigated as a method of forming insoluable waste conditions.

International Nuclear Information System (INIS)

In this report, research and development results on the bituminization of radioactive wastes are closely reviewed, especially those regarding waste treatment technologies, waste solidifying procedures and the characteristics of asphalt and solidified forms. A new concept of the bituminization method is suggested in this report which can improve the characteristics of solidified forms. Stable solid forms with high leach resistance, high thermal resistance and good compression strength were produced by the suggested bituminization method, in which spent polyethylene from agricultural farms was added. This report can help further research and development of improved bituminized forms of radioactive wastes that will maintain long term stabilities in disposal sites. (author). 59 refs., 19 tabs., 18 figs

British Library Electronic Table of Contents (United Kingdom)

In this paper we provide a geochemical investigation on 34 groundwater samples in the Mt. Vulture volcanic aquifer representing one of the most important groundwater resources of the southern Italy pumped for drinking and irrigation supply. The present study includes the first data on the abundance and mobility of minor and trace elements and the thermodynamic considerations on water-rock interaction processes in order to evaluate the conditions of alkali basalt weathering by waters enriched in magma-derived CO2. The results highlight the occurrence of two hydrofacies: bicarbonate alkaline-earth and alkaline waters deriving from low-temperature leaching of volcanic rocks of Mt. Vulture, and bicarbonate-sulfate-alkaline waters (high-salinity waters) related to prolonged water circulation in...

British Library Electronic Table of Contents (United Kingdom)

Abstract Aims: To develop a new nano composite of multi walled carbon nanotubes (MWNTs) with enhanced antimicrobial activity. Methods and Results: A novel antimicrobial nanocomposite [MWNT epilson polylysine (MEPs)] was synthesized via covalent attachment of epilson polylysine on MWNTs with hexamethylene diisocyanate (HDI) as the coupling agent. UV visible spectra and Fourier transform infrared spectra (FT IR) investigations indicate that MEPs is stable, with epilson polylysine leaching effectively eliminated. When compared to MWNTs, the new nano composite MEPs exhibits enhanced antimicrobial activities. In 20 mg l 1 suspensions, significant increases of 72 1, 64 5 and 69% against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus can be observed. The deposited film of MEPs...

British Library Electronic Table of Contents (United Kingdom)

A electrogenerated chemiluminescence (ECL) sensor for itopride was developed based on tris(2,2-bipyridyl)ruthenium(II) (Ru(bpy)32+)-doped silica (RuDS) nanoparticles/biopolymer chitosan composites membrane modified glassy carbon electrode (GCE). The RuDS nanoparticles (52+-5nm) were prepared by a modified Stber synthesis method and were characterized by electrochemical, fluorometric and transmission electron microscopy technology. The Ru(bpy)32+ encapsulation interior of the silica nanoparticle maintains its electrochemical activities and also reduces Ru(bpy)32+ leaching from the silica matrix when immersed in water due to the electrostatic interaction. The ECL analytical performances of this ECL sensor for itopride based on its enhancement ECL emission of Ru(bpy)32+ were investigated in d...

British Library Electronic Table of Contents (United Kingdom)

Changes in the properties of solonetzic soil associations (chestnut solonetzic soils and chestnut solonetzes) in the dry steppe after their reclamation have been studied for 30 years. The reclamation included the deep three-tier plowing and the approach of rotary tillage. A single rotary tillage operation resulted in the formation of fine aggregates of equal sizes in the plow layer; any morphological features of the restoration of solonetzic pedogenesis are absent. The atmospheric moisture easily penetrates into the soil, and soluble salts are leached off to a great depth. In 30 years since the soil amelioration with the use of a PMS-70 rotary tiller, the humus content has increased up to 3.3% in the upper 20-cm-thick layer and up to 2.4% in the layer of 20?40 cm. The content of adsorbed N...

Energy Technology Data Exchange (ETDEWEB)

Acid mine drainage is probably the most important problem facing the mining industry. In this study, the authors evaluated different techniques for the remediation of mine tailings. An in situ characterization of the Aldermac mine tailings was conducted and the results were presented in this poster presentation. The site characterization was performed to determine the extent of the contamination, and sampling of soils was also performed for laboratory experiments in soil covers. The authors described the methodology followed in the laboratory experiments. Chemical analysis of the leaching water was performed to determine its composition in metals. Microbiological analysis was also conducted, as well as the determination of the water saturation index. The authors indicated that they will analyze the results further. tabs., 12 figs.

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

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KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

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KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

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KoreaScience (Korea)

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KoreaScience (Korea)

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KoreaScience (Korea)

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International Nuclear Information System (INIS)

Finnish (May 1971). Finland Kilpelaeinen, JE Imatran Voima Osakeyhtio,

Science.gov (United States)

This paper is dedicated to the treatment of sludge occurring in frame of the Egyptian produced from oil and gas production. The activity levels of three radium isotopes: Ra-226 (of U-series), Ra-228 and Ra-224 (of Th-series) in the solid TENORM waste (sludge) were first evaluated and followed by a sequential treatment for all radium species (fractions) presented in TENORM. The sequential treatment was carried out based on two approaches 'A' and 'B' using different chemical solutions. The results obtained indicate that the activity levels of all radium isotopes (Ra-226, Ra-228 and Ra-224) of the environmental interest in the TENORM waste sludge were elevated with regard to exemption levels established by IAEA [International Atomic Energy Agency (IAEA), International basic safety standards for the protection against ionizing radiation and for the safety of radiation sources. GOV/2715/Vienna, 1994]. Each approach of the sequential treatment was performed through four steps using different ...

International Nuclear Information System (INIS)

A preliminary geologic investigation was conducted to determine if Triassic sedimentary rocks of the Sanford basin and Colon cross structure in North Carolina are favorable hosts for uranium deposits. Rocks of adjacent Carolina slate belt were also examined as a potential source of uranium. On the basis of favorability criteria for sandstone-type uranium deposits, and geologic and geophysical investigations of the study area, the most favorable sites for further investigation are (1) at the contacts between the Pekin and Cumnock and between the Pekin and Sanford Formations near the Colon cross structure and (2) at the base of the Jonesboro fault, which lies below the Sanford Formation, northwest of Sanford. The highly weathered granites southeast of the Jonesboro fault were a source of the detritus deposited on the cross structure and may have been a primary source of uranium. Uranium leached from the coarse sediment (Pekin Formation) of the cross structure may ...

Energy Technology Data Exchange (ETDEWEB)

The chemical fixation of tritium in stearic acid followed by embedding the tritiated stearic acid into an epoxy resin proved to be a good method for permanent waste disposal of tritium gas. Tc-126 and Tc-136 hardener were used for this purpose. The polymerization temperature of the polymer products was found to be highly decreased by adding stearic acid and slightly decreased by adding stearic acid or by raising the temperature of the leachant medium and slightly decreased by irradiation. On the other hand, small improvement in the compressive strength of the polymer products was achieved by adding silica powder. The polymer product showed high flame points above 573 K although it contains stearic acid. DTA and TG analysis indicate that the thermal stability of polymer products containing stearic acid and silica powder is better than samples containing only stearic acid. Stearic acid was found to possess good resistance to irradiation and the amount of hydrogen and oxygen gases ...

Energy Technology Data Exchange (ETDEWEB)

All power plant engineers face the problem of peak power demands. Pumped storage plants are used to generate peak load power by pumping up water utilizing off-peak energy of hydrothermal and thermonuclear plants. This is a reference to cover hydroelectric power generation with emphasis on engineering to meet peak power demands by means of pumped storage plants, tidal power plants, and low head power generation. Text covers hydrology, mechanical and electrical equipment, accessories such as penstocks and valves, and civil engineering considerations. Contains descriptions of several existing plants. Includes 200 diagrams and 50 photographs.

UK PubMed Central (United Kingdom)

The rolB gene of Agrobacterium rhizogenes, whose expression stimulates the formation of roots by transformed plant tissues and other growth alterations in transgenic plants, codes for a beta-glucosidase...Full Text Available

UK PubMed Central (United Kingdom)

Plants have too long been ignored as useful screening and monitoring systems of environmental mutagens. However, there are about a dozen reliable, some even unique, plant genetic systems that can increase...Full Text Available

UK PubMed Central (United Kingdom)

The effect of plant water deficit on ethylene production by intact plants was tested in three species, beans (Phaseolus vulgaris L.), cotton (Gossypium hirsutum L.)...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

This paper evaluates a new power tower concept that offers significant benefits for commercialization of power tower technology. The concept uses a molten nitrate salt centralreceiver plant to supply heat, in the form of combustion air preheat, to a conventional combined-cycle power plant. The evaluation focused on first commercial plants, examined three plant capacities (31, 100, and 300 MWe), and compared these plants with a solar-only 100-MWe plant and with gas-only combined-cycle plants in the same three capacities. Results of the analysis point to several benefits relative to the solar-only plant including low energy cost for first plants, low capital cost for first plants, reduced risk with respect to business uncertainties, and the potential for new markets. In addition, ...

Energy Technology Data Exchange (ETDEWEB)

Originally designed exclusively for peak load covering, pumped storage plants are now faced with new challenges brought about by the deregulation of the electricity market and the substantial growth of wind power capacity. Today's pumped storage plants are started more frequently and often for shorter periods of time. The grid controlling tasks have increased the importance of the role played by this type of power plant and improved sales considerably. But the operational demands have grown substantially as well. This paper discusses the ensuing adaptation of power plant operation as well as options available to power plant operators. (orig.)

Energy Technology Data Exchange (ETDEWEB)

The purpose of the chapter is to explain briefly the various considerations that enter into determining the general layout or arrangement of typical hydroelectric powerplants, pumping plants, and pumped-storage plants. Some of the important factors that affect or determine the location, type, and layout of the plant and the selection of the major items of equipment included in the installation are outlined in this chapter. The first consideration in the design of a powerplant, pumping plant, or pumped-storage plant is that it adequately perform its function and be structurally safe. The structure is also designed to give a pleasing architectural appearance.

Energy Technology Data Exchange (ETDEWEB)

Identifying stable isotope variation and mineralogical changes in fractured rock may help establish the history of climatic and geomorphological processes that might affect the isolation properties of a waste repository site. This study examines the use of the stable isotope ratios of oxygen ({sup 18}O/{sup 16}O) and carbon ({sup 13}C/{sup 12}C) in authigenic minerals as hydrogeochemical tools tracing low-temperature rock-water interaction in variably-saturated fractured stuff. Isotopic compositions of fracture-filling and rock matrix minerals in the Apache Leap tuff, near Superior, Arizona were concordant with geothermal temperatures and in equilibrium with water isotopically similar to present-day meteoric water and groundwater. Oxygen and carbon isotope ratios of fracture-filling, in unsaturated fractured tuff, displayed an isotopic gradient believed to result from near-surface isotopic enrichment due to evaporation rather than the effects of rock-water interaction. Oxygen isotope ...

Energy Technology Data Exchange (ETDEWEB)

Coal bed natural gas (CBNG) development in the Powder River (PR) Basin produces modestly saline, highly sodic wastewater. This study assessed impacts of wetting four textural groups (0-11%, 12-22%, 23 -33%, and > 33% clay (g clay/100 g soil) x 100%))with simulated PR or CBNG water on water retention. Soils received the following treatments with each water quality: a single wetting event, five wetting and drying events, or five wetting and drying events followed by leaching with salt-free water. Treated samples were then resaturated with the final treatment water and equilibrated to -10, -33, -100, -500, or -1,500 kPa. At all potentials, soil water retention increased significantly with increasing clay content. Drought-prone soils lost water-holding capacity between saturation and field capacity with repeated wetting and drying, whereas finer textured soils withstood this treatment better and had increased water-retention capacity at lower matric potentials.

Energy Technology Data Exchange (ETDEWEB)

The International Atomic Energy Agency (IAEA) started the Coordinated Research Program entitled ```The Safety Assessment of Near-Surface Radioactive Waste Disposal Facilities.`` The program is aimed at improving the confidence in the modeling results for safety assessments of waste disposal facilities. The program has been given the acronym NSARS (Near-Surface Radioactive Waste Disposal Safety Assessment Reliability Study) for ease of reference. The purpose of this report is to present the ORNL modeling results for the first test case (i.e., Test Case 1) of the IAEA NSARS program. Test Case 1 is based on near-surface disposal of radionuclides that are subsequently leached to a saturated-sand aquifer. Exposure to radionuclides results from use of a well screened in the aquifer and from intrusion into the repository. Two repository concepts were defined in Test Case 1: a simple earth trench and an engineered vault.

Energy Technology Data Exchange (ETDEWEB)

Monitoring of groundwater quality from boreholes in and around the former Yotsugi open-pit mining site in the Ningyo-toge Environmental Engineering Center, JNC, have been carried out to estimate extent and quality of contaminated water plume from the buried heap-leaching residue. In this report, data collected from 1979 to 1998 fiscal year were listed and their spatial and time variation of physicochemical parameters, uranium and radium were also summarized. Additionally, groundwater sampler has been improved and analytical method has been modified. Some results from groundwater quality were; 1. Generally, electric conductivity and concentrations of uranium and radium outside of the site tend to lower than one from the inside area. 2. Data from borehole No. 13, installed outside of the site, exceptionally little higher than one from the inside area. (author)

Energy Technology Data Exchange (ETDEWEB)

Applications using microwave energy in the chemical processing industry have increased within the last ten years. Recently, interest in waste treatment applications process development, especially solidification, has grown. Microwave waste processing offers many advantages over conventional waste treatment technologies. These advantages include a high density, leach resistant, robust waste form, volume and toxicity reduction, favorable economics, in-container treatment, good public acceptance, isolated equipment, and instantaneous energy control. The results from the {open_quotes}cold{close_quotes} demonstration scale testing at the Rocky Flats nuclear weapons facility are described. Preliminary results for a transuranic (TRU) precipitation sludge indicate that volume reductions of over 80% are achievable over the current immobilization process. An economic evaluation performed demonstrated cost savings of $11.68 per pound compared to the immobilization process ...

Environmental Research Database

ObjectivesThe overall objective of the proposal is to test the conclusions reached in a recent article by Magnani, Mencuccini et al (2007), in which we proposed for the first time that the Net Ecosystem Productivity (NEP) of forests of the temperate and boreal region does not depend on temperature or rainfall but, rather, on nitrogen deposition (Ndep) from the atmosphere. It is widely accepted that Ndep can increase forest C sequestration, however the results from our 2007 paper reported a sensitivity dC/ [continued...]DescriptionCombustion of fossil fuels and use of fertilisers in agriculture has increased the amount of nitrogen compounds present in the atmosphere and the biosphere. More atmospheric nitrogen is converted into reactive nitrogen by anthropogenic activities than by all natural processes combined. This phenomenal historical increase in nitrogen deposition is responsible for several serious environmental problems, such as soil acidification and nitrogen saturation, nitrate ...

Energy Technology Data Exchange (ETDEWEB)

The presence of iron and manganese in underground water due to rock leaching may cause problems in drinking water. the oxidation of these metals produces precipitates which alter water quality (by making it cloudy and bad testing) and may even block supply pipes. This article presents a way eliminating this problem which was tried out in the conduits of Cantillana, a municipality in the province of Seville, Spain. Cleaning the pipes with a mixture of H{sub 2}O{sub 2} + water changes the characteristics of the deposits from flocculant and absorbent to sandy following which they are washed away by the pressure of the water. Once the pipes have been cleaned, a minimal amount of maintenance will prevent the formation of new deposits. This article thus a relatively simple and economical solution for recovering water quality as an alternative to the complicated replacement of the whole network. (Author) 7 refs.

British Library Electronic Table of Contents (United Kingdom)

The effects of anthropogenic (nitrogen fertilization) and natural [soil texture, pH content of humus, ammonium nitrogen (N-NH4), and the available forms of phosphorus (P), potassium (K), magnesium (Mg)] factors on nitrate nitrogen (NO3-N) content and distribution were shown. The dependencies between these factors and the content of NO3-N in soil were estimated in three soil layers: 0-30 cm; 31-60 cm; 61-90 cm. The research was carried out in 2004-2006, and the soil samples were taken from 411 places throughout eastern Poland in two seasons: spring and autumn. The concentration of NO3-N significantly depended on the year of investigation, season of the year, and depth of sampling. Distribution of NO3-N in the soil profile indicates possibility of NO3 leaching during winter and early spring....

CERN Document Server

Design of energy efficient schemes for data gathering is an important concern for lifetime enhancement of wireless sensor networks. Variation in the distances of nodes from the Base Station and differences in inter-nodal distances are primary factors causing unequal energy dissipation among the nodes. Thus energy difference between the various nodes increases with time resulting in degraded network performance. The LEACH and PEGASIS schemes which provided elegant solutions to the problem suffer basic drawbacks due to randomization of cluster heads and greedy chain formation respectively. In this paper, we propose an Optimized Lifetime Enhancement (OLE) Scheme which shows enhanced performance over these schemes. OLE increases the network performance by ensuring a sub-optimal energy dissipation of the individual nodes despite their random deployment. It employs modern heuristics like particle swarm optimization instead of the greedy algorithm as in PEGASIS to ...

UK PubMed Central (United Kingdom)

OBJECTIVE--The study was performed to examine the influence of the exposure to magnetic fields in the potrooms of an electrolysis plant on the occurrence of musculoskeletal symptoms among the employees....Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Eighteen species of Thai rutaceous plants were investigated for their essential oil contents and compositions. Of these plants, four genera belong to the tribe Citreae. Monoterpenes and sesquiterpenes were commonly found in the essential oils of these plants species while phenylpropanoids were present only as minor components. The distribution of these monoterpenes and sesquiterpenes in each plant produce its characteristic smell. The plants of Clauseneae appeared to be rich sources of sesquiterpenes while these of Citreae were found to contain both monoterpenes and sesquiterpenes. In terms of chemical composition, one hundred and forty-three components were detected from the 18 selected rutaceous plants. The distribution and diversity of these components among the selected plants have been discussed. (author)

Energy Technology Data Exchange (ETDEWEB)

This report presents the results of a study on Operation and Maintenance (O M) practices in hydroelectric pumped storage plants. The objective of this project, which was sponsored by EPRI, is to record the practical knowledge on the O M of a number of the domestic and foreign pumped storage plants which has been accumulated by their operating staff. Civil, geotechnical, mechanical and electrical aspects of O M of the thirty-five plants visited are discussed, and some general conclusions, as warranted by the commonality of the problems, are drawn. These conclusions may be useful to the planners and designers of future pumped storage projects. In general, due to their layout, diversity and different modes of operation, the plants have few common problems which, in most cases, are limited to the mechanical and electrical aspects of the plants' operation. The data on ...

Energy Technology Data Exchange (ETDEWEB)

Many higher plants produce economically important organic compounds such as oils, resins, tannins, natural rubber, gums, waxes, dyes, flavors and fragrances, pharmaceuticals, and pesticides. However, most species of higher plants have never been described, much less surveyed for chemical or biologically active constituents, and new sources of commercially valuable materials remain to be discovered. Advances in biotechnology, particularly methods for culturing plants cells and tissues, should provide new means for the commercial processing of even rare plants and the chemicals they produce. These new technologies will extend and enhance the usefulness of plants as renewable resources of valuable chemicals. In the future, biologically active plant-derived chemicals can be expected to play an increasingly significant role in the commercial development of new ...

International Nuclear Information System (INIS)

... reactor intake canals intake structures nuclear power plants safety seismic

Energy Technology Data Exchange (ETDEWEB)

This paper focuses on the application and features of a unified multi-machine train condition monitoring and diagnostic system as applied to a 340 MW repowered combined cycle power plant. Modifications during repowering of the plant required the addition of gas turbines, and design changes to the boiler and steam turbine. Operational procedure during startup also had to be developed. In order to improve the economics of operation, enhancement of both plant operational efficiency and availability were required. Thus it was decided to implement an on-line plant-wide multi-machine Condition Monitoring System. In this paper, the details of the condition monitoring system and some of the design details of the power plant are presented. Requirements of a condition monitoring system applicable to a combined cycle plant are also covered. Salient system design features ...

Energy Technology Data Exchange (ETDEWEB)

Fully-fired combined cycle plants utilizing the high temperature gas turbine discharge as gas intake for a coal-fired steam generator were developed in the 1960's. Long-term experience and the excellent reliability statistics of the gas turbines of these plants have proven that the thermodynamic, economical and ecological advantages of combined cycle units over conventional units strongly suggest such plants for fossil-fuel applications. This paper describes the design and operation of these plants. Topics are Gersteinwerk Unit K combined-cycle power plant, plant design concept, design criteria and performance, gas turbines, steam generators, steam turbines, various modes of operation, typical plant start-up, environmental considerations, prototype plants and topping old steam turbine ...

International Nuclear Information System (INIS)

Published in summary form only.

Energy Technology Data Exchange (ETDEWEB)

Some general topical information (generating capacity and electric power generation, development and structure of electric power consumption, frequency and peak load, exchange of electricity) is followed by an account of the situation of coal-fired power plants, hydroelectric power plants and nuclear power plants, and a brief discussion of the environmental situation (emissions and wastes, immissions, and air pollution abatement measures for power plants). (orig./UA).

KoreaScience (Korea)

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International Nuclear Information System (INIS)

Technetium transfer from soil to edible parts of various agricultural plants is studied with application of the "9"5"mTc radioactive tracer. The samples of agricultural plants were grown on andesol typical for Japan soil. The technetium transfer factor to edible parts of cultivated lettuce was higher as compared to non foliate cultures. Relative low transfer factor were observed for fruit and pod like plants. the transfer factors for root crops were of intermediate value

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

KoreaScience (Korea)

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International Nuclear Information System (INIS)

1973. 43 p. United States Anon. American Society of Mechanical

International Nuclear Information System (INIS)

The general requirements applicable to the quality assurance of the Finnish nuclear power plants are presented in the Council of State Decision (395/91) and in the guide YVL 1.4. This guide specifies the quality assurance requirements to be applied during the operation of the nuclear power plants as well as of the other nuclear facilities. Quality assurance applies to all the activities and organizations with a bearing on the safe operation of the nuclear power plants. (5 refs.).

KoreaScience (Korea)

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Wastenet

...Assemblages of plants and invertebrate animals of tumulus (organic mound) springs of the Swan Coastal Plain Assemblages of plants and invertebrate animals of tumulus ...organic mound) springs of the Swan Coastal Plain [Skip navigation links] About us | Contact us | Publications |...ecological communities Assemblages of plants and invertebrate animals of tumulus (organic mound) springs of the Swan Coastal Plain Advice to the Minister for the ...of the 'Assemblages of plants and invertebrate animals of tumulus (organic mound) springs of the Swan Coastal Plain' community sufficient to distinguish it from ...

International Science & Technology Center (ISTC)

Development of a Plant for Neon Isotopes Separation by Low-Temperature Rectification Method

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

Short communication.

KoreaScience (Korea)

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International Nuclear Information System (INIS)

This is a manuscript for a lecture contents: 1. Steam power and fundamentals of the steam power process, 2. conventional, nuclear and other steam generation processes, 3. cooling systems for steam power plants, 4. gas turbine power plants and combined-cycle power plants, 5. cogeneration, 6. development of thermal power plants and environmental effects. (orig.).

KoreaScience (Korea)

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Wastenet

for municipal waste iron ore sinter plants incinerators for clinical waste facilities of the non-ferrous metal

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

Short communication

KoreaScience (Korea)

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DEFF Research Database (Denmark)

Udgivelsesdato: October 2004

Energy Technology Data Exchange (ETDEWEB)

Adding capacity to coal-fired plants in small increments of an overall integrated program may be the solution to the 10-year lead time required for the construction of a new plant. A preliminary study evaluates the technical and economic feasibility of a modular natural gas and coal-fired combined-cycle power plant which can be installed in three distinct phases. The plant sizes are suitable for large industrial and utility applications. The Modular Block Power Plant (MBPP) concept offers the advantages of phase construction, lower capital cost, lower cost electricity, lower air emissions, lower water requirements, and reduced solid waste discharge. Other advantages include part load availability, reduced coal inventory requirements, and easier plant siting. 11 figures, 4 tables.

Science.gov (United States)

The focus of the March-April issue is on plant maintenance and plant life extension. Major articles/reports in this issue include: Spent fuel: myths and facts, by Jeffrey S. Merrifield, U.S. Nuclear Regulatory Commission; Critical pipe replacement procedure, by Geoff Gilmore, Climax Portable Machine Tools Inc.; Improving maintenance performance, by Larry Meyer and Joe Giuffre, DC Cook Nuclear Plant, American Electric Power; Equipment deficiency intolerance index, by Douglas F. Helms, Tennessee Valley Authority; Plant profile: I and C modernization at Dukovany, by Josef Rosol, CEZ Dukovany NPP, Czech Republic; and, Report: new plant activities.

International Nuclear Information System (INIS)

The design, construction and operation of a pilot plant are often important stages in the development of a project for the production of uranium concentrates. Since building and operating a pilot plant is very costly and may not always be required, it is important that such a plant be built only after several prerequisites have been met. The main purpose of this guidebook is to discuss the objectives of a pilot plant and its proper role in the overall project. Given the wide range of conditions under which a pilot plant may be designed and operated, it is not possible to provide specific details. Instead, this book discusses the rationale for a pilot plant and provides guidelines with suggested solutions for a variety of problems that may be encountered. This guidebook is part of a series of Technical Reports on uranium ore processing being prepared by the ...

British Library Electronic Table of Contents (United Kingdom)

Research in concentrated thermal solar power plants of all types and, in particular, those based on central receiver, namely solar tower plants, has experienced great impetus in the last decade, reaching full commercial operation with the PS10 plant in Spain. In spite of previous demonstration plants testing different receivers and power cycle layouts, this first commercial power plant adopted a cavity receiver generating saturated steam and therefore penalising cycle efficiency in order to gain plant reliability. According to the experience gained, if a competitive Levelised Cost of Electricity is to be reached, capital and maintenance costs must be reduced and efficiencies must be increased. To achieve these goals, modifying the power cycle is deemed essential, whether using superheated ...

Energy Technology Data Exchange (ETDEWEB)

Binary geothermal plants were investigated for providing electrical power for MX missile bases. A number of pure hydrocarbons and hydrocarbon mixtures were evaluated as working fluids for geothermal resource temperatures of 365, 400, and 450/sup 0/F. Cycle thermodynamic analyses were conducted for pure geothermal plants and for two types of coal-geothermal hybrid plants. Cycle performance results were presented as net geofluid effectiveness (net plant output in watts per geofluid flow in 1 bm/hr) and cooling water makeup effectiveness (net plant output in watts per makeup water flow in 1 bm/hr). A working fluid containing 90% (mass) isobutane/10% hexane was selected, and plant statepoints and energy balances were determined for 20MW(e) geothermal plants at each of the three resource temperatures. Working fluid heaters and condensers were ...

Energy Technology Data Exchange (ETDEWEB)

A case study of a small-scale hydroelectric plant to identify implementation problems is presented. The Montello hydroelectric plant is described including the background and history of the plant, the physical characteristics, the financial history and costs, operation, regulatory agencies, and the problems encountered in its operation. The analyses of the energy and capacity (demand) credits for the Montello hydroelectric plant when it is added to the Wisconsin Power and Light Company generating system is described. The WP and L base case and the results of the analyses are discussed. (WHK)

International Nuclear Information System (INIS)

The elemental analysis of some plant samples have been carried out in Trabzon region (Turkey) using energy-dispersive X-ray fluorescence (EDXRF) spectrometry. We have analyzed plant samples for nine stations using 1.85 GBq 55Fe radioactive sources. We have found that potassium and calcium within 0.3-1.4% and 0.3-2.8% were present in concentration in plants for every station, respectively. The concentration of Cl and Ti generally changed according to the plant species and the sampling station.

International Nuclear Information System (INIS)

Despite the fact that there is still a potential to improve the efficiency of classic brown coal power plants by various measures from 36% to approx. 40-41%, the essential big increase of the efficiency to values of approx. 46% can only be achieved by the transition to combined gas and steam turbine processes. This means for the solid fuel brown coal that a gasification is integrated into the power plant process. The combined cycle power plant with an integrated brown coal gasification represents this new power plant concept. The applied High Temperature Winkler method (HTW-method) is an advancement of the Winkler method that works at environmental pressure and was developed by the Rheinbraun AG. (orig./DG).

Energy Technology Data Exchange (ETDEWEB)

This report summarizes work performed on this project from October 2004 through March 2005. In previous work, a surfactant modified zeolite (SMZ) was shown to be an effective system for removing BTEX contaminants from produced water. Additional work on this project demonstrated that a compost-based biofilter could biodegrade the BTEX contaminants found in the SMZ regeneration waste gas stream. However, it was also determined that the BTEX concentrations in the waste gas stream varied significantly during the regeneration period and the initial BTEX concentrations were too high for the biofilter to handle effectively. A series of experiments were conducted to determine the feasibility of using a passive adsorption column placed upstream of the biofilter to attenuate the peak gas-phase VOC concentrations delivered to the biofilter during the SMZ regeneration process. In preparation for the field test of the SMZ/VPB treatment system in New Mexico, a pilot-scale SMZ system was also ...

International Nuclear Information System (INIS)

The present guidelines supplement the 'VGB guidelines for the reduction of noise in thermal power plants' with indications for the ordering and quality assurance of the individual noise-producing machines and equipment of power plant operation. These guides are to simplify the commissioning and delivering for the orderer and deliverer. In addition, these guidelines are to lead to a successful cooperation of all parties in the reduction of the sound radiation. A precondition for this is an explanation of the sound technical demands which must be made on the single machines or mechanical equipment in power plant systems. A protection of the neighbourhood as well as operational personnel against noise according to the state of technology is to be achieved by a clear form of ordering and quality assurance. The ordering and assurance procedure for all aggregates in the region of the grounds of a power plant ...

Energy Technology Data Exchange (ETDEWEB)

This Maintenance Implementation Plan (MIP) has been developed for maintenance functions associated with the B Plant/WESF (Waste Encapsulation Storage Facility) complex. The objective of this plan is to provide baseline information for establishing and identifying WHC conformance programs and policies applicable to implementation of DOE order 4330.4B guidelines. In addition, this maintenance plan identifies the actions necessary to develop a cost-effective and efficient maintenance program at B Plant/WESF. The B Plant WESF facility complex consists of three main facilities and several support structures located in the 200 East Area of the Hanford site. B Plant is a transition facility that is required to ensure safe storage and management of WESF (operating facility) cesium and strontium capsules. B Plant/WESF also contains substantial radiological inventory from previous campaigns. ...

Energy Technology Data Exchange (ETDEWEB)

The competitiveness of a new nuclear plant vs. a new oil or gas fired combined cycle plant or a coal fired plant in East-Asia, is reviewed in the paper. Both the nuclear and the fossil fired plants are evaluated as either utility financed or independent power producer (IPP) financed. Two types of advanced light water reactors (ALWRs) are considered in this paper, namely evolutionary ALWRs (1200 MWe size) and passive ALWRs (600 MWe class). A range of capital and total generation costs for each plant type is reported here. The comparison centers on three elements of overall competitiveness: generation costs, hard currency requirements, and employment requirements. Each of these aspects is considered perspective. Year-by-Year generation cost history over the plant lifetime is shown in some cases. It is found here that a utility financed evolutionary and passive ...

International Nuclear Information System (INIS)

The world's fleet of nuclear power plants is, on average, more than 20 years old. Even though the design life of a nuclear power plant is typically 30-40 years, it is quite feasible that many plants will be able to operate in excess of their design lives, provided that nuclear power plant engineers demonstrate by analysis, trending, equipment and system upgrades, increased vigilance, testing and ageing management that the plant will operate safely. In the operation of nuclear power plants, safety should be always the prime consideration. Plant operators and regulators must always ensure that plant safety is maintained, and where possible enhanced, during a plant's operating lifetime. Nuclear power plant life management (PLiM) has gained increased attention over the past decade, ...

Energy Technology Data Exchange (ETDEWEB)

This engineering report compiles information on types and quantities of liquid waste discharged from B-Plant directly to cribs, ditches, reverse wells, etc., that are associated with B-Plant. Waste discharges to these cribs via overflow form 241-B, 241-BX, and 241-BY tank farms, and waste discharged to these cribs from sources other than B-Plant are discussed.Discharges from B-Plant to other cribs, unplanned releases, or waste remaining in tanks are not included in the report. Waste stream composition information is used to predict quantities of individual chemicals sent to cribs. This provides an accurate mass balance of waste streams from B-Plant to these cribs. These predictions are compared with known crib inventories as a verification of the process.

British Library Electronic Table of Contents (United Kingdom)

Summary 1. Plants express multiple defensive traits, but little is known about the genetic stability and phenotypic plasticity of these traits in nature. To investigate sources of variation and their potential ecological consequences for herbivores, we combined field observations of cyanogenic lima bean with laboratory experiments. 2. Field studies in South Mexico revealed a distinct variability of cyanogenic traits within and among wild lima bean populations. To differentiate among genetic variation and the impact of ambient conditions on plant phenotypes, we used seed grown plants as well as clones propagated from high (HC) and low cyanogenic (LC) wild type plants. 3. In growth chamber experiments, we cultivated plants under three intensities each of drought and salt stress, nutrient sup...

Energy Technology Data Exchange (ETDEWEB)

In order to determine the viability of any Liquids from Coal (LFC) commercial venture, TEK-KOL and its partner, Mitsubishi Heavy Industries (MHI), have put together a technical and economic feasibility study for a commercial-size LFC Plant located at Zeigler Coal Holding Company`s North Rochelle Mine site. This resulting document, the ENCOAL Mild Coal Gasification Plant: Commercial Plant Feasibility Study, includes basic plant design, capital estimates, market assessment for coproducts, operating cost assessments, and overall financial evaluation for a generic Powder River Basin based plant. This document and format closely resembles a typical Phase II study as assembled by the TEK-KOL Partnership to evaluate potential sites for LFC commercial facilities around the world.

Energy Technology Data Exchange (ETDEWEB)

This paper develops optimal bidding strategies for a pumped-storage plant in a pool-based electricity market. In the competitive regime, when compared to simple hydroelectric generator, profit of the pumped-storage plant is maximized by operating it as a generator when market clearing price is high and as a pump when the price is low. Based on forecasted hourly market clearing price, a multistage looping algorithm to maximize the profit of a pumped-storage plant is developed, considering both the spinning and non-spinning reserve bids and meeting the technical operating constraints of the plant. The proposed model is adaptive for the nonlinear three-dimensional relationship between the power produced, the energy stored, and the head of the associated reservoir. Different operating cycles for a realistic pumped-storage plant are considered and simulation results are reported and ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Steam generation is an integral part of most chemical process plants; however, the steam plant often is or can be overlooked in the area of hazard analysis. The reasons for this oversight are obvious: steam generation is considered to be an old and well-understood process, and steam boiler systems are often not considered to pose the same hazards as other plant units. However, modern steam boiler systems are fueled with natural gas, pulverized coal, and/or fuel oil; each of which poses significant fire and explosion hazards. For example, a moderately sized chemical plant's boiler house may have two or three boilers operating at 240 MMBTU/hr, with each using approximately 11 ton/hr of subbituminous pulverized coal feed. Chemical plants rely on equipment design and installation, mai...

Science.gov (United States)

The Wolsung-1 CANDU 600 MWe plant is now in operation. This paper provides an update on the design, construction and commissioning progress reported at last year's conference. The accomplishments of the past year are highlighted with emphasis on how the s...

UK PubMed Central (United Kingdom)

For terrestrial animals and plants, a fundamental cost of living is water vapor lost to the atmosphere during exchange of metabolic gases. Here, by bringing together previously developed models for...Full Text Available

UK PubMed Central (United Kingdom)

Several years of research on seven different plants (five terrestrial and two aquatic species) suggest that the beneficial effects of atmospheric CO₂ enrichment may be divided into three...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Japan has upwards of 40 pumped storage plants in operation and new river sites are becoming scarce, but peak demand is still rising. A plant under construction in Okinawa offers a solution: make use of the head between the coastal cliffs and sea level, using seawater as the medium. (author)

International Nuclear Information System (INIS)

Requirements for the installation, inspection, and testing that assure the quality of important components of a nuclear power plant during construction are presented.

UK PubMed Central (United Kingdom)

Digestion of plant chromatin from Brassica pekinensis and Matthiola incana with staphylococcus nuclease leads to a DNA repeat of 175 plus or minus 8 and a core size of 140 base pairs. DNase I digestion...Full Text Available

International Nuclear Information System (INIS)

In this paper, the compulsory site requirements and the site design assumptions which are being used for the present ITER plant are briefly described. A set of different parameters from the site design assumptions is also described, which was adopted as an additional exercise for cost sensitivity analysis of the ITER plant for these parameters. (orig.)

Energy Technology Data Exchange (ETDEWEB)

In this study, sensitivity analysis of 100 MWth chemical looping combustion combined cycle (CLC-CC) plant based on fuel cost were performed. By performance analysis, net efficiency of natural gas/syngas fueled CLC-CC plant was 53-54%, corresponding to previous research. We used Chemical Engineering Plant Cost Index and Guthrie method to evaluate plant cost. For syngas fueled CLC-CC plant, the plant cost was higher since lower heating value (LHV) of syngas was lower than that of natural gas and cost of electricity (COE) was also higher since the cost of syngas was higher than that of natural gas. By sensitivity analysis, it was shown that the cost of syngas should be less than 5.3 $/GJ in order to make COE lower than 5.8 c/kWh which was COE of natural gas CLC-CC plant. 15 refs., 2 figs., 5 tabs.

UK PubMed Central (United Kingdom)

Rhizosphere acidification by Fe-deficient bean (Phaseolus vulgaris L.) plants was induced by trace amounts of divalent metal ions (Zn, Mn). The induction of this Fe-efficiency reaction...Full Text Available

International Nuclear Information System (INIS)

This guide describes an acceptable method of complying with the Commission's regulations with regard to the quality assurance requirements for the packaging, shipping, receiving, storage, and handling of items for water-cooled nuclear power plants.

UK PubMed Central (United Kingdom)

A new method is described for continuously measuring cell turgor pressure (P), hydraulic conductivity (L_p), and volumetric elastic modulus (ε) in higher plant cells, using a pressure...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

This article puts the case for coal fired combined cycle gas turbine (CCGT) power plants. The need to gasify the coal for the CCGT, use of fluidised bed combustors or gasification systems, the difference in prices of coal and natural gas, and coal and natural gas reserves are discussed. (UK)

Energy Technology Data Exchange (ETDEWEB)

The article describes control and monitoring concepts in which the delegation of responsibility is becoming more decisive than ever (automation hierarchy), and which are capable of optimized, automatic control of process events in pumped storage plants. 8 refs.

Wastenet

Pumped storage plants 20 are a relatively common type.They use a dam to create an upper reservoir ...Some pumped storage plants use the same water turbine and electric generator for both operating periods.That is,

UK PubMed Central (United Kingdom)

Auxin modulates diverse plant developmental pathways through direct transcriptional regulation and cooperative signaling with other plant hormones. Genetic and biochemical approaches have clarified...Full Text Available

UK PubMed Central (United Kingdom)

Chrysomelid leaf beetles use chemical defenses to overcome predatory attack and microbial infestation. Larvae of Chrysomela lapponica that feed on willow sequester plant-derived salicin...Full Text Available

International Nuclear Information System (INIS)

This standard provides the general requirements used in the design, construction, testing, and commissioning of concrete containment structures for CANDU nuclear power plants designated as class containment and is directed to the owners, designers, manufacturers, fabricators, and constructors of the concrete components and parts.

Energy Technology Data Exchange (ETDEWEB)

The various steps of gas treatment in the Sasol II coal liquefaction plant are discussed: CO/sub 2/ removal, separation of the hydrocarbon fractions and the recirculated hydrogen by low-temperature decomposition, production of pure hydrogen by alternating pressure absorption.

UK PubMed Central (United Kingdom)

Traditional plant use in Nepal has been documented for millennia. The importance of plants as medicine has not diminished in any way in recent times, and traditional medicines are still the most important...Full Text Available

UK PubMed Central (United Kingdom)

We investigated the effects of wastewater treatment plant (WWTP) discharge on the ecology of bacterial communities in the sediment of a small, low-gradient stream in South Australia. The quantification...Full Text Available

UK PubMed Central (United Kingdom)

We discuss the relationship between the dynamically changing tension gradients required to move water rapidly through the xylem conduits of plants and the proportion of conduits lost through embolism...Full Text Available