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Systems and economic analysis of microalgae ponds for conversion of CO{sub 2} to biomass. Quarterly technical progress report, September 1993--December 1993

Description: This report provides an economic analysis and feasibility study for the utilization by microalgal systems of carbon dioxide generated from coal-fired power plants. The resulting biomass could be a fuel substitute for fossil fuels.
Date: January 15, 1994
Creator: Benemann, J. R. & Oswald, W. J.
Partner: UNT Libraries Government Documents Department

Energy and protein production from pulp mill wastes. Annual report, June 15, 1977--June 15, 1978

Description: Studies on desugared spent sulfite liquor, DSSL, subjected to ozonation indicate that this complex organic substrate in water solution reacts readily with ozone to produce lower molecular weight organic fragments which can be metabolized by a variety of microorganisms. Ozone uptake is complete up to approximately 15 g/l and results in an increase of 35% BOD and a reduction of 16% COD. The production of BOD is pH dependent with a maximum occurring at aroung pH 3. The production of methane via fermentation of DSSL is greatly enhanced by the ozonation reaction. Methane production on raw DSSL is only 45.3 standard cc/1 of DSSL. After ozonation of the DSSL during which 15 g/l of ozone are reacted, the resulting product yields 1239 standard cc/1. The hypothesis that methane is produced from acetic acid, held by several prior workers, could not be corroborated in this study. Liquor remaining in the fermenter after gas production has essentially ceased in much richer in acetic acid than ozonated DSSL. Continuous fermentation studies operated to optimize gas production produced a fermentate containing 3.96 g/l of acetic acid. The production of protein accomplished through the growth of Torula yeast on DSSL is also enhanced by the ozonation reaction. Two variants show minimal growth on unozonated DSSL but cell densities of 5 g/l were obtained with the rough variant when this substrate has been ozonated. In contrast to the methane fermentation which showed high ozone consumption to be beneficial, the yeast prefer very minimal ozone reaction. Yeast growth was not vigorous on methane fermentate shown to be rich in acetic acid.
Date: June 15, 1978
Creator: Jurgensen, M.F. & Patton, J.T.
Partner: UNT Libraries Government Documents Department

Slag waste heat recovery and utilization in the elemental phosphorus industry. Final report, October 28, 1977--April 30, 1978

Description: Approximately 80 x 10/sup 12/ Btu/y of thermal energy are contained in molten slags produced by the elemental phosphorus industry, the iron and steel industry, the copper industry, and wet-bottom coal-fired boilers. This study evaluates the technical, economic, and environmental feasibility of recovering this wasted energy; the impact of slag waste-heat recovery on the industries in question; and the steps necessary to commercialize applicable heat recovery technology. The study considered two approaches to recovering thermal energy from phosphorus slag: the float chamber and the contact tower. Based on these approaches, nine energy recovery options for converting the energy in slag into other usable forms of energy were conceptualized and economically evaluated. All nine options are considered tecnically feasible and environmentally sound. The economics of the nine options are based on 33.9 kg/s (269,000 lb/h) of slag throughput and vary with both the energy from produced and the realizable total credits for different energy forms. Slag by-product credit is generally needed to make heat recovery economically attractive. Slag waste-heat recovery offers considerable potential for energy savings in the elemental phosphorus, iron and steel, and copper industries. Additional studies are recommended to determine if sufficient by-product credits can be obtained to justify this technology economically.
Date: May 15, 1978
Creator: Ctvrtnicek, T.E.; McCormick, R.J.; Serth, R.W.; Wojtowicz, A. & Zanders, D.L.
Partner: UNT Libraries Government Documents Department

District heating and cooling systems for communities through power plant retrofit and distribution network. Final report. Volume I. Text

Description: An analysis was performed investigating the potential of retrofitting Detroit Edison's Conners Creek power plant to supply district heating and cooling to an area surrounding the plant and within the City of Detroit. A detailed analysis was made of the types and ages of the buildings in the service area as a basis for establishing loads. The analysis of the power plant established possible modifications to the turbines to serve the load in the area. Based upon the service area data and plant retrofit schemes, a distribution system was developed incrementally over a 20-y period. An economic analysis of the system was performed to provide cash flows and payback periods for a variety of energy costs, system costs, and escalation rates to determine the economic viability of the system analyzed. The legal and regulatory requirements required of the district heating and cooling system owner in Michigan were also analyzed to determine what conditions must be met to own and operate the system.
Date: September 15, 1979
Partner: UNT Libraries Government Documents Department

Benson Beach Demonstration Project: Composition and Abundance of Biota at Three Alternative Sump Sites

Description: The Portland District of the U.S. Army Corps of Engineers is investigating plans to provide sediment to nourish beaches north of the Mouth of the Columbia River (MCR). Under the currently designed proposal, sediment dredged from the MCR will be temporarily stored at one of three proposed areas south of the North Jetty before being redredged and moved by a cutterhead pipeline dredge over the jetty to nourish Benson Beach. Resulting potential impacts to resident Dungeness crab (Cancer magister) and fishes represent one of the criteria for evaluating each of the alternative locations. To establish the species composition and relative abundance of crabs and fishes associated with each of the three proposed sump areas, researchers from the Pacific Northwest National Laboratory Marine Sciences Division completed nine field sampling trips from July 8, 2003, to November 1, 2003, for a total of 113 successful trawls comprising an area of over 7.4 ha (74,156 m2). This report documents the results of that effort. To understand the relative risk of losses to crab populations associated with dredging impacts at the sump alternative areas, it is recommended that a modified dredge impact model be developed using the data collected in this study. This model should estimate crab adult equivalent loss and associated error rates to gain a population-level perspective on the potential entrainment impacts at each of the three alternative sump areas. As well, a sustained survey of Dungeness crab distribution and movement within the Columbia River estuary would clarify the relative value of the sump areas as a migratory corridor for crab populations, and support management decisions relative to issues associated with dredged material handling and disposal.
Date: January 15, 2004
Creator: Williams, Greg D.; Pearson, Walter H.; Evans, Nathan R. & Anderson, Michael G.
Partner: UNT Libraries Government Documents Department

Biphase turbine bottoming cycle for a diesel engine

Description: Application of a two-phase turbine system to waste heat recovery was examined. Bottoming cycle efficiencies ranging from 15 to 30% were calculated for a 720/sup 0/F diesel exhaust temperature. A single stage demonstration unit, designed for non-toxic fluids (water and DowTherm A) and for atmospheric seals and bearings, had a cycle efficiency of 23%. The net output power was 276 hp at 8,100 rpm, increasing the total shaft power from 1,800 hp for the diesel alone, to 2,076 hp for the combined system. A four stage organic turbine, for the same application, had a rotational speed of 14,700 rpm while a four stage steam turbine had 26,000 rpm. Fabrication drawings were prepared for the turbine and nozzle. The major improvement leading to higher cycle efficiency and lower turbine rpm was found to be the use of a liquid component with lower sensible heat. A reduction in capital cost was found to result from the use of a contact heat exchanger instead of tube-fin construction. The cost for a contact heat exchanger was only $35-52/kWe compared to $98/kWe for a tube-fin heat exchanger. Design drawings and materials list were prepared. A program resulting in the demonstration of a two-phase bottoming system was planned and the required cost estimated. The program would result in a feasibility test of the nozzle and turbine at the end of the first year, a laboratory performance test of the bottoming system by the end of the second year and a field demonstration test and laboratory endurance test of the bottoming system during the third year. The blowdown test rig for the first year's program and test turbine were designed.
Date: February 15, 1977
Creator: Ahmad, S. & Hays, L.
Partner: UNT Libraries Government Documents Department

The production of chemicals from food processing wastes using a novel fermenter separator. Annual progress report, January 1993--March 1994

Description: The basic objective of this project is to convert waste streams from the food processing industry to usable fuels and chemicals using novel bioreactors. These bioreactors should allow economical utilization of waste (whey, waste sugars, waste starch, bottling wastes, candy wastes, molasses, and cellulosic wastes) by the production of ethanol, acetone/butanol, organic acids (acetic, lactic, and gluconic), yeast diacetyl flavor, and antifungal compounds. Continuous processes incorporating various processing improvements such as simultaneous product separation and immobilized cells are being developed to allow commercial scale utilization of waste stream. The production of ethanol by a continuous reactor-separator is the process closest to commercialization with a 7,500 liter pilot plant presently sited at an Iowa site to convert whey lactose to ethanol. Accomplishments during 1993 include installation and start-up of a 7,500 liter ICRS for ethanol production at an industry site in Iowa; Donation and installation of a 200 liter yeast pilot Plant to the project from Kenyon Enterprises; Modeling and testing of a low energy system for recovery of ethanol from vapor is using a solvent absorption/extractive distillation system; Simultaneous saccharification/fermentation of raw corn grits and starch in a stirred reactor/separator; Testing of the ability of `koji` process to ferment raw corn grits in a `no-cook` process.
Date: March 15, 1994
Creator: Dale, M. C.; Venkatesh, K. V.; Choi, H.; Salicetti-Piazza, L.; Borgos-Rubio, N.; Okos, M. R. et al.
Partner: UNT Libraries Government Documents Department


Description: As advanced gasification technology is increasingly adopted as an energy source, disposal of the resulting slag will become a problem. We have shown that gasifier slag can be incorporated into foamed glass, which is currently being manufactured as an abrasive and as an insulating material. The slag we add to foamed glass does not simply act as filler, but improves the mechanical properties of the product. Incorporation of gasifier slag can make foamed glass stronger and more abrasion resistant.
Date: March 15, 2006
Creator: Norton, Olin Perry; Palmer, Ronald A. & Ramsey, W. Gene
Partner: UNT Libraries Government Documents Department

Utilization of coal associated minerals. Quarterly report No. 10, January 1-March 31, 1980

Description: In the preceding quarterly report, it was reported that while sampling the Solvent Refined Coal II (SRC II) pilot plant at Fort Lewis, Washington, the plant went down and vacuum bottoms waste material representing the minerals flow at the last steady state condition were obtained. This plant has been sampled again and samples of the incoming feed coal, sized coal and vacuum bottoms waste material were obtained. As part of our effort to trace the same mineral suite through mining, preparation and conversion, new samples of feed coal, cleaned coal and refuse were obtained from the District 4 commercial preparation plant. This preparation plant supplies coal to the SRC II pilot plant at Fort Lewis, Washington. A study of the thermal insulating properties of fired flyash based structural materials was completed and is included.
Date: July 15, 1980
Creator: Slonaker, J. F.; Buttermore, W. H.; Carlisle, J. A.; Durham, D. L.; Muter, R. B. & Alderman, J. K.
Partner: UNT Libraries Government Documents Department