WorldWideScience

Sample records for central heating plants

  1. The Marstal Central Solar Heating Plant

    DEFF Research Database (Denmark)

    Heller, Alfred; Jochen, Dahm

    1999-01-01

    The central solar heating plant in Marstal is running since 1996 and has been monitored since. The resulting data from the plant is analysed and the plant performance evaluated. A TRNSYS-model (computersimulation) id prepared and validated based on the measured data from the plant. Acceptable good...

  2. Central solar heating plants with seasonal storage

    Energy Technology Data Exchange (ETDEWEB)

    Breger, D.S.; Sunderland, J.E.

    1989-03-01

    The University of Massachusetts has recently started a two year effort to identify and design a significant Central Solar Heating Plant with Seasonal Storage (CSHPSS) in Massachusetts. The work is closely associated with the U.S. participation in the International Energy Agency (IEA) Task on CSHPSS. The University is working closely with the Commonwealth of Massachusetts to assist in identifying State facilities as potential sites and to explore and secure State support which will be essential for product development after the design phase. Currently, the primary site is the University of Massachusetts, Amherst campus with particular interest in several large buildings which are funded for construction over the next 4-5 years. Seasonal thermal energy storage will utilize one of several geological formations.

  3. Optimisation of Control Strategy at the Central Solar Heating Plant in Marstal, Denmark

    DEFF Research Database (Denmark)

    Heller, Alfred

    1999-01-01

    The central solar heating plant at Marstal is monitored since 1996. The data is analysed with focus on the applied constrol strategy for the solar collector field. Variable flow is applied which is not the case at the other plants compared. The project analysed the performance, compared...... the performance with other control strategies and made proposals for furher enhancements....

  4. Central Heating Plant site characterization report, Marine Corps Combat Development Command, Quantico, Virginia

    Energy Technology Data Exchange (ETDEWEB)

    1990-08-01

    This report presents the methodology and results of a characterization of the operation and maintenance (O M) environment at the US Marine Corps (USMC) Quantico, Virginia, Central Heating Plant (CHP). This characterization is part of a program intended to provide the O M staff with a computerized artificial intelligence (AI) decision support system that will assist the plant staff in more efficient operation of their plant. 3 refs., 12 figs.

  5. Heat deposition into the superconducting central column of a spherical tokamak fusion plant

    Science.gov (United States)

    Windsor, C. G.; Morgan, J. G.; Buxton, P. F.

    2015-02-01

    A key challenge in designing a fusion power plant is to manage the heat deposition into the central core containing superconducting toroidal field coils. Spherical tokamaks have limited space for shielding the central core from fast neutrons produced by fusion and the resulting gamma rays. This paper reports a series of three-dimensional computations using the Monte Carlo N-particle code to calculate the heat deposition into the superconducting core. For a given fusion power, this is considered as a function of plasma major radius R0, core radius rsc and shield thickness d. Computations over the ranges 0.6 m ⩽ R0 ⩽ 1.6 m, 0.15 m ⩽ rsc ⩽ 0.25 m and 0.15 m ⩽ d ⩽ 0.4 m are presented. The deposited power shows an exponential dependence on all three variables to within around 2%. The additional effects of source profile, the outer shield and shield material are all considered. The results can be interpolated to 2% accuracy and have been successfully incorporated into a system code. A possible pilot plant with 174 MW of fusion is shown to lead to a heat deposition into the superconducting core of order 30 kW. An estimate of 1.7 MW is made for the cryogenic plant power necessary for heat removal, and of 88 s running time for an adiabatic experiment where the heat deposition is absorbed by a 10 K temperature rise.

  6. Exergy and Thermoeconomic Analyses of Central Receiver Concentrated Solar Plants Using Air as Heat Transfer Fluid

    Directory of Open Access Journals (Sweden)

    Claudia Toro

    2016-10-01

    Full Text Available The latest developments in solar technologies demonstrated that the solar central receiver configuration is the most promising application among concentrated solar power (CSP plants. In CSPs solar-heated air can be used as the working fluid in a Brayton thermal cycle and as the heat transfer fluid for a Rankine thermal cycle as an alternative to more traditional working fluids thereby reducing maintenance operations and providing the power section with a higher degree of flexibility To supply thermal needs when the solar source is unavailable, an auxiliary burner is requested. This configuration is adopted in the Julich CSP (J-CSP plant, operating in Germany and characterized by a nominal power of 1.5 MW, the heat transfer fluid (HTF is air which is heated in the solar tower and used to produce steam for the bottoming Rankine cycle. In this paper, the J-CSP plant with thermal energy storage has been compared with a hybrid CSP plant (H-CSP using air as the working fluid. Thermodynamic and economic performances of all the simulated plants have been evaluated by applying both exergy analysis and thermoeconomic analysis (TA to determine the yearly average operation at nominal conditions. The exergy destructions and structure as well as the exergoeconomic costs of products have been derived for all the components of the plants. Based on the obtained results, the thermoeconomic design evaluation and optimization of the plants has been performed, allowing for improvement of the thermodynamic and economic efficiency of the systems as well as decreasing the exergy and exergoeconomic cost of their products.

  7. Value impact assessment: A preliminary assessment of improvement opportunities at the Quantico Central Heating Plant

    Energy Technology Data Exchange (ETDEWEB)

    Brambley, M.R.; Weakley, S.A.

    1990-09-01

    This report presents the results of a preliminary assessment of opportunities for improvement at the US Marine Corps (USMC) Quantico, Virginia, Central Heating Plant (CHP). This study is part of a program intended to provide the CHP staff with a computerized Artificial Intelligence (AI) decision support system that will assist in a more efficient, reliable, and safe operation of their plant. As part of the effort to provide the AI decision support system, a team of six scientists and engineers from the Pacific Northwest Laboratory (PNL) visited the plant to characterize the conditions and environment of the CHP. This assessment resulted in a list of potential performance improvement opportunities at the CHP. In this report, 12 of these opportunities are discussed and qualitatively analyzed. 70 refs., 7 figs., 6 tabs.

  8. Boiling water reactor in a prestressed reinforced concrete vessel for an atomic central heating-and-power plant

    Energy Technology Data Exchange (ETDEWEB)

    Tokarev, Yu.I.; Sokolov, I.N.; Skvortsov, S.A.; Sidorov, A.M.; Krauze, L.V.

    1978-04-01

    The possibility of using a boiling water reactor in a prestressed reinforced concrete vessel for an atomic central heating-and-power plant (CHPP) was considered, with design features of the reactor intended for a two-purpose plant. A prestressed reinforced concrete vessel and integral arrangement of the primary circuit ensured reliability of the atomic CHPP using various CHPP flowsheets.

  9. The production of hot sanitary water by condensing boilers: Analysis of the seasonal experimental results of a central heating plant

    Energy Technology Data Exchange (ETDEWEB)

    Caliari, R.; Cirillo, E.; Lazzarin, R.; Piccininni, F.

    1988-12-01

    The use of condensing boilers in the production of hot sanitary water clearly evidences their advantages, since the highest operating temperatures are only around 60/degree/C. This paper examines performance test results relevant to a central heating plant (serving a residential area in Rovereto, Italy) with 112 kW of thermal power. The analysis reveals the excellent performance characteristics of the condensing boilers and points out the importance of proper management of the recirculation system.

  10. Do heat and smoke increase emergence of exotic and native plants in the matorral of central Chile?

    Science.gov (United States)

    Figueroa, Javier A.; Cavieres, Lohengrin A.; Gómez-González, Susana; Montenegro, Marco Molina; Jaksic, Fabian M.

    2009-03-01

    We studied the effect of heat shock and wood-fueled smoke on the emergence of native and exotic plant species in soil samples obtained in an evergreen shrubland of central Chile, located on the eastern foothills of the Coastal Range of Lampa. Immediately after collection samples were dried and stored under laboratory condition. For each two transect, 10 samples were randomly chosen, and one of the following treatments was applied: 1) Heat-shock treatment. 2) Plant-produced smoke treatment. 3) Combined heat-and-smoke treatment. 4) Control, corresponding to samples not subjected to treatment. Twenty-three species, representing 12 families, emerged from the soil samples. The best-represented families were Poaceae and Asteraceae. All of the emerged species were herbs, 21 were annuals, and 14 were exotic to Chile. Fire-related triggers used in this study did not increase the emergence and/or abundance of exotic species with respect to natives in soil samples. Interestingly, this study provides evidence that heat-shock can increase the emergence of native herbs.

  11. Gas power plants heat the public mind;Les centrales a gaz echauffent les esprits

    Energy Technology Data Exchange (ETDEWEB)

    Chauveau, L.

    2009-11-15

    Nuclear energy provides most part of the electricity produced in France but fossil thermal plants remain necessary to face peaking demand. The French government has planned to replace all the fossil plants by combined cycle gas plants that release far less CO{sub 2} than classic coal or oil plants. 31 new gas plants have been authorized and among them 2 are operating, 10 are being built and 8 are at the project stage. In some projects like in the little town of Verberie (Oise department) these projects are facing a strong local opposition. The objection of the opponents is two-fold: -) the plant will have a strong negative impact on the wild life particularly the population of boars and stags and -) this huge program of 31 gas plants contradict the government that committed itself to reduce the consumption of fossil energies and to favor renewable energies through its Grenelle environmental policy. (A.C.)

  12. Preliminary design study of a central solar heating plant with seasonal storage at the University of Massachusetts, Amherst

    Science.gov (United States)

    Breger, D. S.; Sunderland, J. E.

    1991-04-01

    This report documents the design development and selection of the final preliminary design of a Central Solar Heating Plant with Seasonal Storage (CSHPSS) for the University of Massachusetts in Amherst (UMass). The effort has been performed by the Department of Mechanical Engineering at UMass under contract with the U.S. Department of Energy. Phase 1 of this project was directed at site selection for the CSHPSS project and was reported earlier. This report focuses on the Phase 2 development of the site conditions and analytical study of project design, performance, and cost. The UMass site presents an excellent opportunity of a CSHPSS project in terms of land availability for a large collector array, a 100 foot deep deposit of soft, saturated clay for seasonal thermal energy storage, and appropriate low temperature heating loads. The project under study represents the first implementation of this solar technology in the United States and results from the International Energy Agency collaboration on CSHPSS since 1979. The preliminary design calls for a large 10,000 m(exp 2) parabolic trough collector array, 70,000 m(exp 3) storage volume in clay with heat transfer through 900 boreholes. Design optimization is based on computer simulations using MINSUN and TRNSYS. The design is expected to provide 95 percent of the 3500 MWh heating and hot water load. A project cost of $3.12 million (plus $240,000 for HVAC load retrofit) is estimated, which provides an annualized cost of $66.2/MWh per unit solar energy delivered. The project will proceed into an engineering phase in Spring 1991.

  13. Mobile central heating plant ensures the supply during the power-plant modernization. Planning-safe reconstruction; Mobile Heizzentrale sichert Versorgung waehrend Kraftwerksmodernisierung. Planungssicherer Umbau

    Energy Technology Data Exchange (ETDEWEB)

    Bernhard, Petra [Mobiheat GmbH, Friedberg (Germany). Presse- und Oeffentlichkeitsarbeit

    2012-09-15

    During the comprehensive energetic retrofitting of district heating plants in the spa resort of Badenweiler (Federal Republic of Germany) a mobile 2-MW heating plant from Mobilheat (Ebersberg, Federal Republic of Germany) was used for the heat supply. Thus, the installation of environmental friendly energy supply based on cogeneration plants could be implemented with planning security. This particularly was important because, among other things, the traditional spa resort, the Kurhaus as well as hotels and private customers depend on the heat supply system. These buildings have be supplied with thermal water also in the summer.

  14. Demonstration of the use of ADAPT to derive predictive maintenance algorithms for the KSC central heat plant

    Science.gov (United States)

    Hunter, H. E.

    1972-01-01

    The Avco Data Analysis and Prediction Techniques (ADAPT) were employed to determine laws capable of detecting failures in a heat plant up to three days in advance of the occurrence of the failure. The projected performance of algorithms yielded a detection probability of 90% with false alarm rates of the order of 1 per year for a sample rate of 1 per day with each detection, followed by 3 hourly samplings. This performance was verified on 173 independent test cases. The program also demonstrated diagnostic algorithms and the ability to predict the time of failure to approximately plus or minus 8 hours up to three days in advance of the failure. The ADAPT programs produce simple algorithms which have a unique possibility of a relatively low cost updating procedure. The algorithms were implemented on general purpose computers at Kennedy Space Flight Center and tested against current data.

  15. Power and Efficiency Analysis of a Solar Central Receiver Combined Cycle Plant with a Small Particle Heat Exchanger Receiver

    Science.gov (United States)

    Virgen, Matthew Miguel

    Two significant goals in solar plant operation are lower cost and higher efficiencies. To achieve those goals, a combined cycle gas turbine (CCGT) system, which uses the hot gas turbine exhaust to produce superheated steam for a bottoming Rankine cycle by way of a heat recovery steam generator (HRSG), is investigated in this work. Building off of a previous gas turbine model created at the Combustion and Solar Energy Laboratory at SDSU, here are added the HRSG and steam turbine model, which had to handle significant change in the mass flow and temperature of air exiting the gas turbine due to varying solar input. A wide range of cases were run to explore options for maximizing both power and efficiency from the proposed CSP CCGT plant. Variable guide vanes (VGVs) were found in the earlier model to be an effective tool in providing operational flexibility to address the variable nature of solar input. Combined cycle efficiencies in the range of 50% were found to result from this plant configuration. However, a combustor inlet temperature (CIT) limit leads to two distinct Modes of operation, with a sharp drop in both plant efficiency and power occurring when the air flow through the receiver exceeded the CIT limit. This drawback can be partially addressed through strategic use of the VGVs. Since system response is fully established for the relevant range of solar input and variable guide vane angles, the System Advisor Model (SAM) from NREL can be used to find what the actual expected solar input would be over the course of the day, and plan accordingly. While the SAM software is not yet equipped to model a Brayton cycle cavity receiver, appropriate approximations were made in order to produce a suitable heliostat field to fit this system. Since the SPHER uses carbon nano-particles as the solar absorbers, questions of particle longevity and how the particles might affect the flame behavior in the combustor were addressed using the chemical kinetics software Chemkin

  16. Production and Use of Densified Refuse-Derived Fuel (DRDF) in Military Central Heating and Power Plants.

    Science.gov (United States)

    1980-03-01

    facility in Los cations required for its reliable use. Subsequently, Gatos , CA. Nearly 21 tons of this material were fired in reasonably reliable cost... bacteria , viruses, and present. pathogens. Research at the Ames, Iowa, resource recov- ery facility found airborne bacteria counts in the plant There has...analysis cated that most of the bacteria (>90 percent of the procedures used render these results inconclusive. The fecal coliform) were associated with the

  17. Cleaning chemical and mechanical of heat exchangers in french nuclear plants; Limpieza mecanica y quimica de intercambiadores de calor en centrales nucleares francesas

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, J. t.; Guerra, P.; Carreres, C.

    2013-03-01

    This project was carried out under the frame of the approval of LAINSA as a supplier of EDF in France. The inspection performed on systems called the moisture separator reheaters (GSS) of CPO series reactor of EDF nuclear power plants has shown evidence of significant clogging due to deposits of magnetite inside the tubes of tube bundle. The pressure drop between inlet and outlet of the heating was close to maximum design criterion. This effect could result in equipment damage and loss of plant productivity. The aim of the work was the design, development, approval and implementation of a procedure for un blocking the tubes of the GSS respecting the integrity of materials and ensuring the harmlessness of cleaning procedures. The procedure used was to completely remove magnetite deposits in order to recover a passage diameter and a surface finish equivalent to the origin, thus avoiding the replacement of the GSS and obtaining a considerable reduction of costs. The achieve these objectives we have developed a procedure that is basically a mechanical pre-cleaning of all tubes of the GSS in order to unblock tem, followed by a chemical cleaning where magnetite is dissolved and crawled out of the tube bundle. The main results were: -Corrosion less than 10 microns. 100-110 Kg of magnetite removed by heat exchanger. -Final pressure drop similar to that of new equipment. -Waste water: 70 m{sup 3} per exchanger, which were managed by an authorized waste management company. This procedure has been applied successfully in 14 GSS type heat exchangers in Fessenheim and Bugey nuclear power plants in France between 2009 and 2011. This project demonstrates that the long experience of LAINSA in the Spanish nuclear industry along with the knowledge and experience in chemical cleaning of SOLARCA, have served to successfully work demanding and mature markets such as the French nuclear market, solving the problem of deposits of magnetite with an effective and safe method for the treated

  18. Diffusion and dispersion heat of hydrotermal discharge from power plant; Difusion y dispersion de calor de la descarga hidrotermal de una central termoelectrica

    Energy Technology Data Exchange (ETDEWEB)

    Rendon Villalobos, J. Rodolfo

    1996-12-31

    This study describe the numerical simulation results of hydrodynamical behavior of the surface discharge cooling water to the sea incoming from the Tuxpan Power Plant under two different meteorological and oceanographic conditions; Case I, southwest variable winds average speeds of 3 m s-1 and Case II, northwest variable winds average speeds of 11.10 m s-1 . The numerical simulations were made using a three-dimensional model of coastal circulation and heat exchange. The statistical analysis of the wind speed and direction time series measured from January 1, 1981 to December 31, 1983, shows that the larger part of the winds were predominantly from 180 degrees to 315 degrees. Therefore, the southerly winds induce a sea surface circulation towards the north which move the discharged heat water away from the intake. On the contrary, the north winds drives the hydrothermal effluent towards the intake. Comparisons between the numerical simulation results and field data show that under different meteorological and oceanographic conditions, representative of the Tuxpan Site, the model correctly predicts the hydrothermal effluents surface diffusion and Dispersion measured on August 19-20 and 21, 1992 (Case I) and November 26, 1992 (Case II). The model predicts the extent of the impacted areas with cooling water with a precision of {+-} 11%. For all analyzed cases, the real size of the impacted areas that might have adverse effects on the marine ecosystems was not gibber than 0.1 km{sup 2}. Thus, these possible adverse effects are considered to be of local significance only. The simulated vertical profiles of temperature show that the cooling water discharged remains mostly o the surface of the receiving water mass and reaches a maximum depth of 3.5 m. This floatability if a consequence of the low density and small Froude number (Fr << 1), at the discharge, that characterizes the Tuxpan Power Plant Effluent. [Espanol] Este estudio describe los resultados de la simulacion

  19. Heat pipe central solar receiver. Volume I. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Bienert, W. B.; Wolf, D. A.

    1979-04-01

    The objective of this project was the conceptual design of a Central Solar Receiver Gas Turbine Plant which utilizes a high temperature heat pipe receiver. Technical and economic feasibility of such a plant was to be determined and preliminary overall cost estimates obtained. The second objective was the development of the necessary heat pipe technology to meet the requirements of this receiver. A heat pipe receiver is ideally suited for heating gases to high temperatures. The heat pipes are essentially loss free thermal diffusers which accept a high solar flux and transform it to a lower flux which is compatible with heat transferred to gases. The high flux capability reduces receiver heating surface, thereby reducing receiver heat losses. An open recuperative air cycle with a turbine inlet temperature of 816/sup 0/C (1500/sup 0/F) was chosen as the baseline design. This results in peak metal temperatures of about 870/sup 0/C (1600/sup 0/F). The receiver consists of nine modular panels which form the semicircular backwall of a cavity. Gas enters the panels at the bottom and exits from the top. Each panel carries 637 liquid metal heat pipes which are mounted at right angle to the gas flow. The evaporators of the heat pipes protrude from the flux absorbing front surface of the panels, and the finned condensors traverse the gas stream. Capital cost estimates were made for a 10 MW(e) pilot plant. The total projected costs, in mid-1978 dollars, range from $1,947 to $2,002 per electrical kilowatt. On the same basis, the cost of a water/steam solar plant is approximately 50% higher.

  20. Stochastic modelling of central heating systems

    DEFF Research Database (Denmark)

    Hansen, Lars Henrik

    1997-01-01

    and the degree Erhvervsforsker (a special Danish degree, equivalent to ``Industrial Ph.D.''). The thesis is mainly concerned with experimental design and system identification for individual components in water based central heating systems. The main contribution to this field is on the nonlinear dynamic...

  1. Flexible implementation of upgrading with mobile central heating plants. Tailor-made solutions; Modernisierung mit mobilen Heizzentralen flexibel umsetzen. Massgeschneiderte Loesungen

    Energy Technology Data Exchange (ETDEWEB)

    Bernhard, Petra [Mobiheat GmbH, Kissing (Germany)

    2011-12-15

    Extensive upgrades or modifications require a temporary disconnection of power supply lines. In order to continuously provide heat in this case and in the case of an unforeseen emergency of heating Mobiheat GmbH (Friedberg, Federal Republic of Germany) provides mobile heat suppliers as a flexible solution for a timely and precise heat supply. The contribution under consideration describes the use of mobile heat suppliers at public utilities in district heating sector.

  2. Demand modelling for central heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Heller, A.

    2000-07-01

    Most researchers in the field of heat demand estimation have focussed on explaning the load for a given plant based on rather few measurements. This approach is simply the only one adaptable with the very limited data material and limited computer power. This way of dealing with the subject is here called the top-down approach, due to the fact that one tries to explain the load from the overall data. The results of such efforts are discussed in the report, leading to inspiration for own work. Also the significance of the findings to the causes for given heat loads are discussed and summarised. Contrary to the top-down approach applied in literature, a here-called bottom-up approach is applied in this work, describing the causes of a given partial load in detail and combining them to explain the total load for the system. Three partial load 'components' are discussed: 1) Space heating. 2) Hot-Water Consumption. 3) Heat losses in pipe networks. The report is aimed at giving an introduction to these subjects, but at the same time at collecting the previous work done by the author. Space heating is shortly discussed and loads are generated by an advanced simulation model. A hot water consumption model is presented and heat loads, generated by this model, utilised in the overall work. Heat loads due to heat losses in district heating a given a high priority in the current work. Hence a detailed presentation and overview of the subject is given to solar heating experts normally not dealing with district heating. Based on the 'partial' loads generated by the above-mentioned method, an overall load model is built in the computer simulation environment TRNSYS. The final tool is then employed for the generation of time series for heat demand, representing a district heating area. The results are compared to alternative methods for the generation of heat demand profiles. Results form this comparison will be presented. Computerised modelling of systems

  3. Central receiver solar thermal power system, Phase 1. CDRL Item 2. Pilot plant preliminary design report. Volume V. Thermal storage subsystem. [Sensible heat storage using Caloria HT43 and mixture of gravel and sand

    Energy Technology Data Exchange (ETDEWEB)

    Hallet, Jr., R. W.; Gervais, R. L.

    1977-10-01

    The proposed 100-MWe Commercial Plant Thermal Storage System (TSS) employs sensible heat storage using dual liquid and solid media for the heat storage in each of four tanks, with the thermocline principle applied to provide high-temperature, extractable energy independent of the total energy stored. The 10-MW Pilot Plant employs a similar system except uses only a single tank. The high-temperature organic fluid Caloria HT43 and a rock mixture of river gravel and No. 6 silica sand were selected for heat storage in both systems. The system design, installation, performance testing, safety characteristics, and specifications are described in detail. (WHK)

  4. Efficiency Analysis of Independent and Centralized Heating Systems for Residential Buildings in Northern Italy

    Directory of Open Access Journals (Sweden)

    Fabio Rinaldi

    2011-11-01

    Full Text Available The primary energy consumption in residential buildings is determined by the envelope thermal characteristics, air change, outside climatic data, users’ behaviour and the adopted heating system and its control. The new Italian regulations strongly suggest the installation of centralized boilers in renovated buildings with more than four apartments. This work aims to investigate the differences in primary energy consumption and efficiency among several independent and centralized heating systems installed in Northern Italy. The analysis is carried out through the following approach: firstly building heating loads are evaluated using the software TRNSYS® and, then, heating system performances are estimated through a simplified model based on the European Standard EN 15316. Several heating systems have been analyzed, evaluating: independent and centralized configurations, condensing and traditional boilers, radiator and radiant floor emitters and solar plant integration. The heating systems are applied to four buildings dating back to 2010, 2006, 1960s and 1930s. All the combinations of heating systems and buildings are analyzed in detail, evaluating efficiency and primary energy consumption. In most of the cases the choice between centralized and independent heating systems has minor effects on primary energy consumption, less than 3%: the introduction of condensing technology and the integration with solar heating plant can reduce energy consumption by 11% and 29%, respectively.

  5. Selection Guidelines for Central Heat Plant Controls.

    Science.gov (United States)

    1994-11-01

    21 PID Controllers ............................................... 22 Combustion Control...Therefore, closed-loop control is preferred for boiler control. PID Controllers Figure 9 shows the basic functions of a closed loop controller

  6. Indoor air pollution by different heating systems: coal burning, open fireplace and central heating.

    Science.gov (United States)

    Moriske, H J; Drews, M; Ebert, G; Menk, G; Scheller, C; Schöndube, M; Konieczny, L

    1996-11-01

    Investigations of indoor air pollution by different heating systems in private homes are described. Sixteen homes, 7 with coal burning, 1 with open fireplace (wood burning) and 8 with central heating have been investigated. We measured the concentrations of carbon monoxide, carbon dioxide and sedimented dust in indoor air, of total suspended particulates, heavy metals and of polycyclic aromatic hydrocarbons in indoor and outdoor air. Measurements were taken during winter (heating period) and during summer (non-heating period). Generally, we found higher indoor air pollution in homes with coal burning and open fireplace than in homes with central heating. Especially, the concentrations of carbon monoxide, sedimented dust and of some heavy metals were higher. In one case, we found also high indoor air pollution in a home with central heating. This apartment is on the ground floor of a block of flats, and the central heating system in the basement showed a malfunctioning of the exhaust system.

  7. Energy analysis of a central domestic hot water heating system equipped with condensing boilers

    Energy Technology Data Exchange (ETDEWEB)

    Cirillo, E.; Lazzarin, R.; Piccininni, F. (Bologna Univ. (Italy). Ist. di Fisica); Caliari, R. (Servizio Energia, Provincia Autonoma di Trento (IT))

    1990-01-01

    An experimental study was carried out on a central plant for the heating of domestic hot water for a block of 143 flats and 15 offices. The behaviour of the condensing boilers serving the plant was examined and the energy costs of recirculation and distribution were analysed. Since the losses due to recirculation are of the same order as the useful energy, the influence of the various parameters on the losses has been studied, and some methods of lowering them are proposed. (author).

  8. ENERGY EFFICIENCY OF DIFFERENT WAYS OF CENTRAL HEATING

    Directory of Open Access Journals (Sweden)

    A. E. Piir

    2015-01-01

    Full Text Available  The article shows the calculation comparison of fuel for producing of heat-line water with a help of different technological installations, transforming (converting high-grade heat from burning process of fuel or in the process of non-reversible heat exchange with coolant (heating agent, or with a help of heat engines, which allow to decrease losses of working efficiency and thus to reduce the use of fuel. There were considered five types of plants beginning from the  simplest  one  up  to  the  most  complex  in  two  variants,  when  the  heat  exchangers and machines are perfect (ideal and when equipment has the known degree of efficiency (perfection:1 water-heat boiler station, working on organic fuel;2 electrical boiler station, obtaining energy on power transmission lines from condensing power station;3 line heater of TPP, obtaining steam from heating turbine;4 line heater CPP, powered by steam from pressure reducing unit;5 heat pump, producing energy on power supply lines from TPP.In this article were investigated three ideal reversible ways of transformation of   high- grade heat into low-grade heat with a help of decreasing and increasing and combined (suggested by the authors heat transformers and their thermodynamic equivalence was shown in this article. And there were suggested universal installation for electric energy generation, cold and heat of two grades for heat-water supply and the heating process on the base of gascompressors   gas turbines. These results are so important (actual for power engineers of the countries with  increasing consumption  of organic  fuel and  its enhancement in  value and realizing programs of energy saving .The analysis shows, that the quality of produced low-grade heat per unit of used high-grade heat for ideal plants (installations is: electrical boiler unit – 0.7;  water boiler unit – 1.0; for heat pump, heating turbine, combined heat transformers   – 4

  9. Changes in the timing, length and heating degree days of the heating season in central heating zone of China

    Science.gov (United States)

    Shen, Xiangjin; Liu, Binhui

    2016-09-01

    Climate change affects the demand for energy consumption, especially for heating and cooling buildings. Using daily mean temperature (Tmean) data, this study analyzed the spatiotemporal changes of the starting date for heating (HS), ending date for heating (HE), length (HL) and heating degree day (HDD) of the heating season in central heating zone of China. Over China’s central heating zone, regional average HS has become later by 0.97 day per decade and HE has become earlier by 1.49 days per decade during 1960–2011, resulting in a decline of HL (‑2.47 days/decade). Regional averaged HDD decreased significantly by 63.22 °C/decade, which implies a decreasing energy demand for heating over the central heating zone of China. Spatially, there are generally larger energy-saving rate in the south, due to low average HDD during the heating season. Over China’s central heating zone, Tmean had a greater effect on HL in warm localities and a greater effect on HDD in cold localities. We project that the sensitivity of HL (HDD) to temperature change will increase (decrease) in a warmer climate. These opposite sensitivities should be considered when we want to predict the effects of climate change on heating energy consumption in China in the future.

  10. Thermal performance of solar district heating plants in Denmark

    DEFF Research Database (Denmark)

    Furbo, Simon; Perers, Bengt; Bava, Federico

    2014-01-01

    The market for solar heating plants connected to district heating systems is expanding rapidly in Denmark. It is expected that by the end of 2014 the 10 largest solar heating plants in Europe will be located in Denmark. Measurements from 23 Danish solar heating plants, all based on flat plate solar...... collectors mounted on the ground, shows measured yearly thermal performances of the solar heating plants placed in the interval from 313 kWh/m² collector to 493 kWh/m² collector with averages for all plants of 411 kWh/m² collector for 2012 and 450 kWh/m² collector for 2013. Theoretical calculations show...... of the cost/performance ratio for solar collector fields, both with flat plate collectors and with concentrating tracking solar collectors. It is recommended to continue monitoring and analysis of all large solar heating plants to document the reliability of the solar heating plants. It is also recommended...

  11. Enhancement of reproductive heat tolerance in plants.

    Directory of Open Access Journals (Sweden)

    John J Burke

    Full Text Available Comparison of average crop yields with reported record yields has shown that major crops exhibit annual average yields three- to seven-fold lower than record yields because of unfavorable environments. The current study investigated the enhancement of pollen heat tolerance through expressing an Arabidopsis thaliana heat shock protein 101 (AtHSP101 that is not normally expressed in pollen but reported to play a crucial role in vegetative thermotolerance. The AtHSP101 construct under the control of the constitutive ocs/mas 'superpromoter' was transformed into cotton Coker 312 and tobacco SRI lines via Agrobacterium mediated transformation. Thermotolerance of pollen was evaluated by in vitro pollen germination studies. Comparing with those of wild type and transgenic null lines, pollen from AtHSP101 transgenic tobacco and cotton lines exhibited significantly higher germination rate and much greater pollen tube elongation under elevated temperatures or after a heat exposure. In addition, significant increases in boll set and seed numbers were also observed in transgenic cotton lines exposed to elevated day and night temperatures in both greenhouse and field studies. The results of this study suggest that enhancing heat tolerance of reproductive tissues in plant holds promise in the development of crops with improved yield production and yield sustainability in unfavorable environments.

  12. International seminar on biomass and fossil fuels co-firing in power plants and heating plants in Europe; Seminaire international sur la cocombustion de biomasse et d'energies fossiles dans les centrales electriques et les chaufferies en Europe

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The aim of the European commission which has fixed to 12% the share of renewable energies in the total energy consumption up to 2010, is to develop the biomass sector. Co-firing is a solution that allows to increase significantly the use of biomass because it does not require important investments. Today, about 150 power plants in Europe use co-firing. An Altener project named 'Cofiring' has ben settled in order to bring together and analyze the European experience in this domain and to sustain and rationalize the design of future projects. The conclusions of this study, coordinated by VTT Energy and which involves CARMEN (Germany), CBE (Portugal), the Danish centre for landscape and planning, ITEBE (France), KOBA (Italy), SLU (Sweden), and EVA (Austria), were presented during this international seminar. (J.S.)

  13. Evaluation of solar-air-heating central-receiver concepts

    Energy Technology Data Exchange (ETDEWEB)

    Bird, S.P.; Drost, M.K.; Williams, T.A.; Brown, D.R.; Fort, J.A.; Garrett-Price, B.A.; Hauser, S.G.; McLean, M.A.; Paluszek, A.M.; Young, J.K.

    1982-06-01

    The potential of seven proposed air-heating central receiver concepts are evaluated based on an independent, uniform of each one's performance and cost. The concepts include: metal tubes, ceramic tubes, sodium heat pipes, ceramic matrix, ceramic domes, small particles, and volumetric heat exchange. The selection of design points considered in the analysis, the method and ground rules used in formulating the conceptual designs are discussed, and each concept design is briefly described. The method, ground rules, and models used in the performance evaluation and cost analysis and the results are presented. (LEW)

  14. Efficient Heat Use from Biogas CHP Plants. Case Studies from Biogas Plants in Latvia

    OpenAIRE

    Dzene, Ilze; Slotiņa, Lāsma

    2013-01-01

    This paper is focusing on efficient heat use from biogas plants. It gives an overview about various biogas heat use options and specifically addresses biogas heat use market in Latvia. In the end three examples from typical agricultural biogas plants in Latvia and their heat use plans are described.

  15. Genetic and epigenetic control of plant heat responses

    Directory of Open Access Journals (Sweden)

    Junzhong eLiu

    2015-04-01

    Full Text Available Plants have evolved sophisticated genetic and epigenetic regulatory systems to respond quickly to unfavorable environmental conditions such as heat, cold, drought, and pathogen infections. In particular, heat greatly affects plant growth and development, immunity and circadian rhythm, and poses a serious threat to the global food supply. According to temperatures exposing, heat can be usually classified as warm ambient temperature (about 22-27℃, high temperature (27-30℃ and extremely high temperature (37-42℃, also known as heat stress for the model plant Arabidopsis thaliana. The genetic mechanisms of plant responses to heat have been well studied, mainly focusing on elevated ambient temperature-mediated morphological acclimation and acceleration of flowering, modulation of plant immunity and circadian clock by high temperatures, and thermotolerance to heat stress. Recently, great progress has been achieved on epigenetic regulation of heat responses, including DNA methylation, histone modifications, histone variants, ATP-dependent chromatin remodeling, histone chaperones, small RNAs, long non-coding RNAs and other undefined epigenetic mechanisms. These epigenetic modifications regulate the expression of heat-responsive genes and function to prevent heat-related damage. This review focuses on recent progresses regarding the genetic and epigenetic control of heat responses in plants, and pays more attention to the role of the major epigenetic mechanisms in plant heat responses. Further research perspectives are also discussed.

  16. Thermoeconomic optimization of a Kalina cycle for a central receiver concentrating solar power plant

    DEFF Research Database (Denmark)

    Modi, Anish; Kærn, Martin Ryhl; Andreasen, Jesper Graa

    2016-01-01

    Concentrating solar power plants use a number of reflecting mirrors to focus and convert the incident solar energy to heat, and a power cycle to convert this heat into electricity. This paper evaluates the use of a high temperature Kalina cycle for a central receiver concentrating solar power plant...... and the economic perspectives, the results suggest that it is not beneficial to use the Kalina cycle for high temperature concentrating solar power plants....... with direct vapour generation and without storage. The use of the ammonia-water mixture as the power cycle working fluid with non-isothermal evaporation and condensation presents the potential to improve the overall performance of the plant. This however comes at a price of requiring larger heat exchangers...

  17. Layouts of trigeneration plants for centralized power supply

    Science.gov (United States)

    Klimenko, A. V.; Agababov, V. S.; Il'ina, I. P.; Rozhnatovskii, V. D.; Burmakina, A. V.

    2016-06-01

    One of the possible and, under certain conditions, sufficiently effective methods for reducing consumption of fuel and energy resources is the development of plants for combined generation of different kinds of energy. In the power industry of Russia, the facilities have become widespread in which the cogeneration technology, i.e., simultaneous generation of electric energy and heat, is implemented. Such facilities can use different plants, viz., gas- and steam-turbine plants and gas-reciprocating units. Cogeneration power supply can be further developed by simultaneously supplying the users not only with electricity and heat but also with cold. Such a technology is referred to as trigeneration. To produce electricity and heat, trigeneration plants can use the same facilities that are used in cogeneration, namely, gas-turbine plants, steam-turbine plants, and gas-reciprocating units. Cold can be produced in trigeneration plants using thermotransformers of various kinds, such as vaporcompression thermotransformers, air thermotransformers, and absorption thermotransformers, that operate as chilling machines. The thermotransformers can also be used in the trigeneration plants to generate heat. The main advantage of trigeneration plants based on gas-turbine plants or gas-reciprocating units over cogeneration plants is the increased thermodynamic power supply efficiency owing to utilization of the waste-gas heat not only in winter but also in summer. In the steam-turbine-based trigeneration plants equipped with absorption thermotransformers, the enhancement of the thermodynamic power supply efficiency is determined by the increase in the heat extraction load during the nonheating season. The article presents calculated results that demonstrate higher thermodynamic efficiency of a gas-turbine-based plant with an absorption thermotransformer that operates in the trigeneration mode compared with a cogeneration gas-turbine plant. The structural arrangements of trigeneration

  18. Penicillium allergic alveolitis: faulty installation of central heating.

    OpenAIRE

    Fergusson, R J; Milne, L J; Crompton, G K

    1984-01-01

    A married couple presented with an illness typical of allergic alveolitis. A careful search of their home revealed a leak in the central heating system with a heavy fungal growth on wet flooring and linoleum. Two species of Penicillium, P chrysogenum and P cyclopium, were isolated from floorboards, linoleum, and settle plates. Antibodies against both these fungi were demonstrated in the serum of both patients by an enzyme linked immunosorbent assay (ELISA). Allergic alveolitis caused by P chr...

  19. 77 FR 8178 - Test Procedures for Central Air Conditioners and Heat Pumps: Public Meeting

    Science.gov (United States)

    2012-02-14

    ...; ] DEPARTMENT OF ENERGY 10 CFR Part 430 Test Procedures for Central Air Conditioners and Heat Pumps: Public... discuss methodologies and gather comments on testing residential central air conditioners and heat pumps... residential central air conditioners and heat pumps that are single phase with rated cooling capacities...

  20. Heat pipe central solar receiver. Semiannual progress report, September 1, 1976--May 31, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Bienert, W. B.; Wolf, D. A.

    1977-09-01

    It is proposed to develop a solar-to-gas heat exchanger for a Central Solar Receiver Power Plant. The concept employs heat pipes to transfer the concentrated solar flux to the gaseous working medium of a Brayton cycle conversion system. During early phases of the program, an open air cycle with recuperator and a turbine inlet temperature of 800/sup 0/C was selected as the optimum design. The predicted cycle efficiency is 33 percent and the overall solar-to-electric efficiency is 20 percent. Three potential receiver configurations were also identified during the initial phases of the program. Optimum heat pipe diameter is approximately 5 cm for all three receiver configurations, and typical lengths are 2 to 3 meters. The required number of heat pipes for a 10 MWe receiver ranges from 2000 to 8000. Heat transport requirements per pipe vary from 4 to 18 Kw. Several wick structures were developed and evaluated in subscale heat pipe tests using sodium as the working fluid. One full scale heat pipe (5 cm diameter by 183 cm long) was developed and tested with sodium as the working fluid.

  1. Testing and plugging power plant heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Sutor, F. [Expando Seal Tools, Inc., Montgomeryville, PA (United States)

    1994-12-31

    Heat Exchanger tubes fail for any number of reasons including but certainly not limited to the cumulative effects of corrosion, erosion, thermal stress and fatigue. This presentation will attempt to identify the most common techniques for determining which tubes are leaking and then introduce the products in use to plug the leaking tubes. For the sake of time I will limit the scope of this presentation to include feedwater heaters and secondary system heat exchangers such as Hydrogen Coolers, Lube Oil Coolers, and nuclear Component Cooling Water, Emergency Cooling Water, Regenerative Heat Recovery heat exchangers.

  2. Baseload Nitrate Salt Central Receiver Power Plant Design Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Tilley, Drake [Abengoa Solar LLC, Lakewood, CO (United States); Kelly, Bruce [Abengoa Solar LLC, Lakewood, CO (United States); Burkholder, Frank [Abengoa Solar LLC, Lakewood, CO (United States)

    2014-12-12

    The objectives of the work were to demonstrate that a 100 MWe central receiver plant, using nitrate salt as the receiver coolant, thermal storage medium, and heat transport fluid in the steam generator, can 1) operate, at full load, for 6,400 hours each year using only solar energy, and 2) satisfy the DOE levelized energy cost goal of $0.09/kWhe (real 2009 $). To achieve these objectives the work incorporated a large range of tasks relating to many different aspects of a molten salt tower plant. The first Phase of the project focused on developing a baseline design for a Molten Salt Tower and validating areas for improvement. Tasks included a market study, receiver design, heat exchanger design, preliminary heliostat design, solar field optimization, baseline system design including PFDs and P&IDs and detailed cost estimate. The baseline plant met the initial goal of less than $0.14/kWhe, and reinforced the need to reduce costs in several key areas to reach the overall $0.09/kWhe goal. The major improvements identified from Phase I were: 1) higher temperature salt to improve cycle efficiency and reduce storage requirements, 2) an improved receiver coating to increase the efficiency of the receiver, 3) a large receiver design to maximize storage and meet the baseload hours objective, and 4) lower cost heliostat field. The second Phase of the project looked at advancing the baseline tower with the identified improvements and included key prototypes. To validate increasing the standard solar salt temperature to 600 °C a dynamic test was conducted at Sandia. The results ultimately proved the hypothesis incorrect and showed high oxide production and corrosion rates. The results lead to further testing of systems to mitigate the oxide production to be able to increase the salt temperature for a commercial plant. Foster Wheeler worked on the receiver design in both Phase I and Phase II looking at both design and lowering costs utilizing commercial fossil boiler

  3. Research on central heating system control strategy based on genetic algorithm

    Science.gov (United States)

    Ding, Sa; Yang, Jianhua; Lu, Wei; Duan, Zhipeng

    2017-03-01

    The central heating is a major way of warming in northeast China in winter, however, the traditional heating method is inefficient, intensifying the energy consumption. How to improve the heating efficiency and reduce energy waste attracts more and more attentions in our country. In this paper, the mathematical model of heat transfer station temperature control system was established based on the structure of central heating system. The feedforward-feedback control strategy was used to overcome temperature fluctuations caused by the pressurized heating exchange system. The genetic algorithm was used to optimize the parameters of PID controller and simulation results demonstrated that central heating temperature achieved well control effect and meet stabilization requirements.

  4. Heat flow, plant design and environmental protection

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R.; Patela, E.A.; Linhoff, B. (Linnhoff March Ltd. (GB))

    The modern requirements for energy management, minimum capital cost for plant design and the reduction of plant emissions are placing what would appear to be conflicting demands upon the plant engineers. However, there is an established technology that can provide assistance. Pinch Technology, developed a few years ago as a tool for saving energy in existing plants during the last period of escalating oil prices, has now become an established tool for debottlenecking, yield improvement and capital cost reduction. More recently, it has been shown that Pinch Technology can also be used with regard to flue gas emissions, waste minimization and the evaluation of waste treatment options. (author).

  5. Water recovery using waste heat from coal fired power plants.

    Energy Technology Data Exchange (ETDEWEB)

    Webb, Stephen W.; Morrow, Charles W.; Altman, Susan Jeanne; Dwyer, Brian P.

    2011-01-01

    The potential to treat non-traditional water sources using power plant waste heat in conjunction with membrane distillation is assessed. Researchers and power plant designers continue to search for ways to use that waste heat from Rankine cycle power plants to recover water thereby reducing water net water consumption. Unfortunately, waste heat from a power plant is of poor quality. Membrane distillation (MD) systems may be a technology that can use the low temperature waste heat (<100 F) to treat water. By their nature, they operate at low temperature and usually low pressure. This study investigates the use of MD to recover water from typical power plants. It looks at recovery from three heat producing locations (boiler blow down, steam diverted from bleed streams, and the cooling water system) within a power plant, providing process sketches, heat and material balances and equipment sizing for recovery schemes using MD for each of these locations. It also provides insight into life cycle cost tradeoffs between power production and incremental capital costs.

  6. Central receiver power plant: an environmental, ecological, and socioeconomic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Davison, M.; Grether, D.

    1977-06-01

    The technical details of the central receiver design are reviewed. Socio-economic questions are considered including: market penetration, air industrial sector model, demands on industry, employment, effluents associated with manufacture of components, strains due to intensive construction, water requirements, and land requirements. The ecological effects in the vicinity of the central receiver plant site are dealt with, with emphasis on effects on land surface, mammals, and reptiles and amphibians. Climatological considerations are reviewed including: desert types, effects of surface albedo modification, effects of aerosols, effects on evaporation rates, the heliostat canopy, effects on turbulent transfer rates, effects on the wind profile, a model of convection about a central receiver plant, and a global scenario. Drawings of heliostat and plant design are included in appendices. (MHR)

  7. Penetration of central heating boilers. Penetratie van centrale verwarmingsketels; Energiezuinige en milieuvriendelijke ketels in woningen

    Energy Technology Data Exchange (ETDEWEB)

    Bais, J.M.; Kant, A.D.; Rouw, M.

    1990-12-01

    The project 'Penetration options for new energy efficient and environment friendly heating techniques in the housing construction' aims at the calculation of market shares of heating techniques in houses for variable conditions. These conditions can be of economic, technical and social-scientific nature. The project concerns: a literature survey of prognoses of the housing supply, the heat demand, heating types and the number of individual central heating (ICV) boilers as well as a market segmentation based on property of the houses; a quantitative market research of the market section replacement/rebuilding by owners/occupants with regard to ICV boilers by means of Discrete Choice Analysis. Based on three policy scenarios the market shares and the penetration of ICV boilers can be determined by means of the analysis of data from the quantitative market survey; and, the calculation of the market shares of ICV boilers in the section new housing and replacement/rebuilding in rented houses, based on the same three scenarios as mentioned above and by means of the so-called Internal Interest Rate (IRV). 27 figs., 22 refs., 42 tabs., 2 apps.

  8. Plant reproduction in the Central Amazonian floodplains : challenges and adaptations

    OpenAIRE

    Ferreira, Cristiane da Silva; Fernandez Piedade, Maria Teresa; Wittmann, Astrid de Oliveira; Franco, Augusto César

    2010-01-01

    Background The Central Amazonian floodplain forests are subjected to extended periods of flooding and to flooding amplitudes of 10 m or more. The predictability, the length of the flood pulse, the abrupt transition in the environmental conditions along topographic gradients on the banks of major rivers in Central Amazonia, and the powerful water and sediment dynamics impose a strong selective pressure on plant reproduction systems. Scope In this review, we examine how the hydrological cycle i...

  9. Success factors for bioenergy production plants in district heating networks; Erfolgsfaktoren fuer Bioenergieanlagen mit Nahwaermenetz am Beispiel evaluierter Biomasseheizwerke

    Energy Technology Data Exchange (ETDEWEB)

    Leuchtweis, Christian [C.A.R.M.E.N. e.V., Straubing (Germany)

    2009-07-01

    Operators of heat supply plants who receive funds from the Bavarian State Ministry for Nutrition, Agriculture and Forestry are obliged to report annually on the operation of their heat supply plants over a period of up to twelve years (formerly five or seven years). For this purpose C.A.R.M.E.N. (Central Agricultural Resource Marketing and Energy Network) has compiled an extensive database which makes it possible to study the results from different perspectives.

  10. 两种利用电厂热量采暖供热的方案比较%Comparison of Two Heating Programs by Using Power Plant Heat

    Institute of Scientific and Technical Information of China (English)

    林俊光; 任渊源; 张卫灵; 崔云素

    2013-01-01

    发电厂有大量的低温余热被浪费,而通过热泵则可以将发电厂循环水的余热回收利用,从而提高热利用效率。基于热泵技术提出了一种汽水双热源供热量可调的集中供热系统,并与常规热电厂供热系统进行对比,认为利用热泵回收发电厂余热具有节能、环保的双重效应。虽然汽水双热源供热量可调集中供热系统的初投资较高,但运行费用较低,仅需3年就可收回投资。%A great deal of low-temperature residual heat is wasted in power plant. Recycling the residual heat of circulating water by heat pump could increase the efficiency of heat utilization. The paper proposes a cen-tral heating system with steam and water heat sources and heat adjustability on the basis of heat pump tech-nology and it compares the central heating system with the conventional heating system in thermal power plants. The paper believes that residual heat recycling by heat pump can save the energy and protect the en-vironment. Though the investment in central heating system with steam and water heat sources and heat ad-justability is high, the cost for operation is lower, and the investment can be returned in three years.

  11. Optimization of operation for combined heat and power plants - CHP plants - with heat accumulators using a MILP formulation

    Energy Technology Data Exchange (ETDEWEB)

    Grue, Jeppe; Bach, Inger [Aalborg Univ. (Denmark). Inst. of Energy Technology]. E-mails: jeg@iet.auc.dk; ib@iet.auc.dk

    2000-07-01

    The power generation system in Denmark is extensively based on small combined heat and power plants (CHP plants), producing both electricity and district heating. This project deals with smaller plants spread throughout the country. Often a heat accumulator is used to enable electricity production, even when the heat demand is low. This system forms a very complex problem, both for sizing, designing and operation of CHP plants. The objective of the work is the development of a tool for optimisation of the operation of CHP plants, and to even considering the design of the plant. The problem is formulated as a MILP-problem. An actual case is being tested, involving CHP producing units to cover the demand. The results from this project show that it is of major importance to consider the operation of the plant in detail already in the design phase. It is of major importance to consider the optimisation of the plant operation, even at the design stage, as it may cause the contribution margin to rise significantly, if the plant is designed on the basis of a de-tailed knowledge of the expected operation. (author)

  12. Indirect heat integration across plants using hot water circles☆

    Institute of Scientific and Technical Information of China (English)

    Chenglin Chang; Yufei Wang; Xiao Feng

    2015-01-01

    Total site heat integration (TSHI) provides more opportunities for energy saving in industry clusters. Some design methods including direct integration using process streams and indirect integration using intermediate-fluid cir-cuits, i.e., steam, dowtherms and hot water, have been proposed during last few decades. Indirect heat integration is preferred when the heat sources and sinks are separated in independent plants with rather long distance. This improves energy efficiency by adaption of intermediate fluid circle which acts as a utility provider for plants in a symbiotic network. However, there are some significant factors ignored in conventional TSHI, i.e. the investment of pipeline, cost of pumping and heat loss. These factors simultaneously determine the possibility and perfor-mance of heat integration. This work presents a new methodology for indirect heat integration in low tempera-ture range using hot water circuit as intermediate-fluid medium. The new methodology enables the targeting of indirect heat integration across plants considering the factors mentioned earlier. An MINLP model with economic objective is established and solved. The optimization results give the mass flow rate of intermediate-fluid, diam-eter of pipeline, the temperature of the circuits and the matches of heat exchanger networks (HENS) automati-cally. Finally, the application of this proposed methodology is il ustrated with a case study.

  13. Uncertainties in the daily operation of a district heating plant

    DEFF Research Database (Denmark)

    Sorknæs, Peter

    Studies have found that district heating (DH) systems should play an important role in future sustainable energy systems, but that DH has to adapt to lower heat demands. This means adapting to reduced operation hours for units essential for DHs integration in other parts of the energy system...... Ringkøbing District Heating is used as a case to investigate what costs market uncertainties can incur on a DH plant. It is found that the market uncertainties in a 4 months simulated period increased Ringkøbing District Heatings costs by less than 1%. Several factors are however not included in this paper....

  14. Nuclear power plant waste heat utilization

    Energy Technology Data Exchange (ETDEWEB)

    Ryther, J.H.; Huke, R.E.; Archer, J.C.; Price, D.R.; Jewell, W.J.; Hayes, T.D.; Witherby, H.R.

    1977-09-01

    The possibility of using Vermont Yankee condenser effluent for commercial food growth enhancement was examined. It was concluded that for the Vermont Yankee Nuclear Station, commercial success, both for horticulture and aquaculture endeavors, could not be assured without additional research in both areas. This is due primarily to two problems. First, the particularly low heat quality of our condenser discharge, being nominally 72 +- 2/sup 0/F; and second, to the capital intensive support systems. The capital needed for the support systems include costs of pumps, piping and controls to move the heated water to growing facilities and the costs of large, efficient heat exchangers that may be necessary to avoid regulatory difficulties due to the 1958 Delaney Amendment to the U.S. Food, Drug and Cosmetics Act. Recommendations for further work include construction of a permanent aquaculture research laboratory and a test greenhouse complex based on a greenhouse wherein a variety of heating configurations would be installed and tested. One greenhouse would be heated with biogas from an adjacent anaerobic digester thermally boosted during winter months by Vermont Yankee condenser effluent. The aquaculture laboratory would initially be dedicated to the Atlantic salmon restoration program. It appears possible to raise fingerling salmon to smolt size within 7 months using water warmed to about 60/sup 0/F. The growth rate by this technique is increased by a factor of 2 to 3. A system concept has been developed which includes an aqua-laboratory, producing 25,000 salmon smolt annually, a 4-unit greenhouse test horticulture complex and an 18,000 square foot commercial fish-rearing facility producing 100,000 pounds of wet fish (brook trout) per year. The aqualab and horticulture test complex would form the initial phase of construction. The trout-rearing facility would be delayed pending results of laboratory studies confirming its commercial viability.

  15. How much Energy is Embodied in your Central Heating Boiler?

    Science.gov (United States)

    Koubogiannis, D.; Nouhou, C.

    2016-11-01

    Life Cycle Analysis (LCA) is an important tool in current research to quantitatively assess energy consumption and environmental impact of a building. In the context of LCA, the Embodied Energy (EE) related to the building and the corresponding Embodied CO2 emissions are valuable data. In such a case, these data concern the constitutive materials of the building and any subsystem, component or equipment in it. Usually, after calculating the mass of these materials, embodied energy values are estimated multiplying them by the corresponding EE coefficients concerning the production of these materials (EEMP). However, apart from transportation energy costs, another part of EE is that consumed for the manufacturing of any item as a finished product. The present work focuses on the manufacturing EE (EEMFG) of central heating boilers in Hellenic dwellings. Six typical boilers of different types are studied. Each of them is analyzed to its constitutive materials and its EEMP is estimated. For four of them, the boiler house where it was constructed in Greece was visited and data were collected. Based on them the corresponding boiler EEMFG values are estimated. The results concerning the EE for material production and manufacturing, as well as the results concerning the corresponding ECO2 values are discussed and assessed. Benchmark values correlating EE and ECO2 with the mass or the heat rate of the boiler are extracted.

  16. Implementing Geothermal Plants in the Copenhagen District Heating System

    DEFF Research Database (Denmark)

    Jensen, Louise Overvad; Hallgreen, Christine Erikstrup; Larsen, Esben

    2003-01-01

    The possibility of implementing geothermal heating in the Copenhagen district-heating system is assessed. This is done by building up general knowledge on the geological factors that influence the development of useable geothermal resources, factors concerning the exploration and utilization...... Danish district heating system is financially sustainable. Added to the other advantages concerning flexibility and the environment, geothermal heating is considered to be a serious proposal for the future power and heating system in Eastern Denmark. Keywords: Geothermal plants, Electricity surplus...... of geothermal energy in Denmark as well as the Danish potential, which, in former investigations, has been found to be around 100.000 PJ annually, and the economical potential is less, about 15 PJ/year. Since a considerable amount of the Danish power supply is tied to weather and the demand for heating...

  17. Analysis of the Impact of Decreasing District Heating Supply Temperature on Combined Heat and Power Plant Operation

    Directory of Open Access Journals (Sweden)

    Bolonina Alona

    2014-12-01

    Full Text Available District heating systems are widely used to supply heat to different groups of heat consumers. The district heating system offers great opportunities for combined heat and power production. In this paper decreasing district heating supply temperature is analysed in the context of combined heat and power plant operation. A mathematical model of a CHP plant is developed using both empirical and theoretical equations. The model is used for analysis of modified CHP plant operation modes with reduced district heating supply temperature. Conclusions on the benefits of new operation modes are introduced.

  18. Effects of passive heating on central blood volume and ventricular dimensions in humans

    DEFF Research Database (Denmark)

    Crandall, C.G.; Wilson, T.E.; Marving, J.;

    2008-01-01

    Mixed findings regarding the effects of whole-body heat stress on central blood volume have been reported. This study evaluated the hypothesis that heat stress reduces central blood volume and alters blood volume distribution. Ten healthy experimental and seven healthy time control (i.e. non-heat...... plus central vasculature (17 +/- 2%), thorax (14 +/- 2%), inferior vena cava (23 +/- 2%) and liver (23 +/- 2%) (all P Udgivelsesdato: 2008/1/1...

  19. Engineering central metabolism - a grand challenge for plant biologists.

    Science.gov (United States)

    Sweetlove, Lee J; Nielsen, Jens; Fernie, Alisdair R

    2016-12-22

    The goal of increasing crop productivity and nutrient-use efficiency is being addressed by a number of ambitious research projects seeking to re-engineer photosynthetic biochemistry. Many of these projects will require the engineering of substantial changes in fluxes of central metabolism. However, as has been amply demonstrated in simpler systems such as microbes, central metabolism is extremely difficult to rationally engineer. This is because of multiple layers of regulation that operate to maintain metabolic steady state and because of the highly connected nature of central metabolism. In this review we discuss new approaches for metabolic engineering that have the potential to address these problems and dramatically improve the success with which we can rationally engineer central metabolism in plants. In particular, we advocate the adoption of an iterative 'design-build-test-learn' cycle using fast-to-transform model plants as test beds. This approach can be realised by coupling new molecular tools to incorporate multiple transgenes in nuclear and plastid genomes with computational modelling to design the engineering strategy and to understand the metabolic phenotype of the engineered organism. We also envisage that mutagenesis could be used to fine-tune the balance between the endogenous metabolic network and the introduced enzymes. Finally, we emphasise the importance of considering the plant as a whole system and not isolated organs: the greatest increase in crop productivity will be achieved if both source and sink metabolism are engineered.

  20. Interaction of Plant Extracts with Central Nervous System Receptors

    Directory of Open Access Journals (Sweden)

    Kenneth Lundstrom

    2017-02-01

    Full Text Available Background: Plant extracts have been used in traditional medicine for the treatment of various maladies including neurological diseases. Several central nervous system receptors have been demonstrated to interact with plant extracts and components affecting the pharmacology and thereby potentially playing a role in human disease and treatment. For instance, extracts from Hypericum perforatum (St. John’s wort targeted several CNS receptors. Similarly, extracts from Piper nigrum, Stephania cambodica, and Styphnolobium japonicum exerted inhibition of agonist-induced activity of the human neurokinin-1 receptor. Methods: Different methods have been established for receptor binding and functional assays based on radioactive and fluorescence-labeled ligands in cell lines and primary cell cultures. Behavioral studies of the effect of plant extracts have been conducted in rodents. Plant extracts have further been subjected to mood and cognition studies in humans. Results: Mechanisms of action at molecular and cellular levels have been elucidated for medicinal plants in support of standardization of herbal products and identification of active extract compounds. In several studies, plant extracts demonstrated affinity to a number of CNS receptors in parallel indicating the complexity of this interaction. In vivo studies showed modifications of CNS receptor affinity and behavioral responses in animal models after treatment with medicinal herbs. Certain plant extracts demonstrated neuroprotection and enhanced cognitive performance, respectively, when evaluated in humans. Noteworthy, the penetration of plant extracts and their protective effect on the blood-brain-barrier are discussed. Conclusion: The affinity of plant extracts and their isolated compounds for CNS receptors indicates an important role for medicinal plants in the treatment of neurological disorders. Moreover, studies in animal and human models have confirmed a scientific basis for the

  1. Comparative ecobalancing accounting of semi-central house heat supply from wood residues; Vergleichende Oekobilanzierung der semi-zentralen Hauswaermebereitstellung aus Holzreststoffen

    Energy Technology Data Exchange (ETDEWEB)

    Biemann, Kirsten

    2015-07-01

    In 2008 almost 40 percent of the German final energy demand was used for room heating and hot water supply. To decrease environmental burdens and to save fossil resources a restructuring of the heating sector is needed. Therefore legislation enforces higher insulation standards of buildings and a more frequent use of renewable energies as well as heating networks. Wood as a renewable and storable energy source is an attractive fuel. However, it must be used as efficiently as possible because of limited wood supplies. Connecting buildings via a heating network is a good option since bigger heating plants can operate at higher efficiencies than small heaters. However, the higher insulation standards of the buildings often oppose the construction of a heating network, because heating networks work best with high energy demands and low network lengths. Therefore the environmental and economic feasibility of new heating networks needs to be checked beforehand. This thesis explores the environmental burdens of different semi- centralized heating networks using wood residues as fuel. A semi- centralized heating network is a network with no more than 500 customers and a heating plant with less than 5 MWth. While wood residues are used in the base load plant, peak load is covered by a gas heating plant. As a method to analyze the potential environmental burdens of the heat supply a life cycle assessment according to ISO 14040/44 is used. Opposed to former life cycle assessment studies, construction and operation of the network is included in the assessment. Even though the environmental impacts of the semi- centralized heating from wood residues are dominated by the heat supply, an observation of the impacts solely at the heating plant is not sufficient. By varying the boundary conditions of the heating network two main contributors to the environmental impacts are found. In addition to the heat production at the plant the type of the buildings in the settlement has a huge

  2. Psychophysical and cerebral responses to heat stimulation in patients with central pain, painless central sensory loss, and in healthy persons.

    Science.gov (United States)

    Casey, Kenneth L; Geisser, Michael; Lorenz, Jürgen; Morrow, Thomas J; Paulson, Pamela; Minoshima, Satoshi

    2012-02-01

    Patients with central pain (CP) typically have chronic pain within an area of reduced pain and temperature sensation, suggesting an impairment of endogenous pain modulation mechanisms. We tested the hypothesis that some brain structures normally activated by cutaneous heat stimulation would be hyperresponsive among patients with CP but not among patients with a central nervous system lesion causing a loss of heat or nociceptive sensation with no pain (NP). We used H(2)(15)O positron emission tomography to measure, in 15 healthy control participants, 10 NP patients, and 10 CP patients, increases in regional cerebral blood flow among volumes of interest (VOI) from the resting (no stimulus) condition during bilateral contact heat stimulation at heat detection, heat pain threshold, and heat pain tolerance levels. Both patient groups had a reduced perception of heat intensity and unpleasantness on the clinically affected side and a bilateral impairment of heat detection. Compared with the HC group, both NP and CP patients had more hyperactive and hypoactive VOI in the resting state and more hyperresponsive and hyporesponsive VOI during heat stimulation. Compared with NP patients, CP patients had more hyperresponsive VOI in the intralaminar thalamus and sensory-motor cortex during heat stimulation. Our results show that focal CNS lesions produce bilateral sensory deficits and widespread changes in the nociceptive excitability of the brain. The increased nociceptive excitability within the intralaminar thalamus and sensory-motor cortex of our sample of CP patients suggests an underlying pathophysiology for the pain in some central pain syndromes.

  3. Production of Virus-free Carnation Plants through Heat Therapy

    Directory of Open Access Journals (Sweden)

    Manisha Mangal

    2004-01-01

    Full Text Available The effect of exposure of carnation plants infected with carnation, latent virus (CLV to two temperature regimes (35 + 2 "C and 40 +2 "C for different periods (1 to 4 weeks revealed thatthe exposure to different temperatures for different periods has a negative correlation with the survival of plants. Whereas only 33.33 per cent plants survived after 4 weeks at 35 + 2 "C, the plants when exposed to 40+ 2 "C for the same period could not tolerate the heat shock. However, only those plants which were exposed to 35 + 2 "C for 4 weeks and those exposed to 40 + 2 "C for 3 weeks were free from CLV. However, because of better survival rate, the higher temperature regime of 40 + 2 "C is recommended for production of virus-tested carnation plants.

  4. Performance analysis of heating plants equipped with condensing boilers

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.M.; Schibuola, L.

    1986-01-01

    The behaviour of the condensing boilers is strictly bound to the temperature of the water coming back from the plant. This temperature depends on the control modes and on the meteorological conditions. The seasonal performance has been computed for a heating plant of a building equipped with a condensing boiler simulating the load at short time intervals through a suitable modification of TRNSYS. The study has been carried out in the climate of Padova. For other towns a rough estimate is proposed.

  5. FACTORS AFFECTING HEAT TOLERANCE IN CROSSBRED CATTLE IN CENTRAL BRAZIL

    Directory of Open Access Journals (Sweden)

    Concepta Margaret McManus

    2014-06-01

    Full Text Available This study compared the adaptation traits in common crosses of crossbred dairy cattle in central Brazil. Twenty animals of each of three genetic groups were used: zebu (Bos indicus, Simmental x Zebu (SZ and Holstein x Zebu (HZ. The test measured variations in rectal temperature (RT, respiration rate (RR and heart rate (HR of animals in the shade and after exposure to the sun, as well as mean daily milk production throughout the lactation period. The procedure was repeated three times. There were significant interactions between test group and genetic group for the traits investigated and the correlations among traits were low. The RR of the crossbred groups may be controlling body temperature in such a way as not to cause an increase in RT. Milk production influenced RR in crossbred cows exposed to the sun, confirming their poorer adaptation in comparison with zebu cows. We observed that the adaptation can be measured in terms of production within the same genetic group. In conclusion, the crosses with European breeds produced more milk than zebu, although they were influenced by heat/solar radiation.

  6. Investigation of bubble behaviours in wet central heating systems

    Directory of Open Access Journals (Sweden)

    Shefik Ali

    2014-03-01

    Full Text Available A series of experimental measurements has been conducted in order to investigate the bubble behaviours through the horizontal pipe line of the domestic wet central heating systems. Obtained results exposed the effect of 90 degree bend, buoyancy forces on bubbly two phase flow patterns and effect of velocity on void fractions and bubble diameters. Distance chosen for the first sight glass (HSG0 was sufficient enough to note the effect of 90 degree bend on void fraction patterns. Due to the effect of 90 degree bend, position of the peak void fractions across the pipe section lowers, with an increase in bulk fluid velocity. Bubbles tend to flow for longer distance at the bottom of the pipe section. Buoyancy force effect is demonstrated with figures for highest bulk fluid velocity at three different positions. Analysis of four different flow rates at two different saturation ratios show reduction for average bubble diameters and void fractions when bulk fluid velocity increases. An attempt to predict bubble dissolution rates across the horizontal pipeline of the system is made, however results show some uncertainties.

  7. Investigation of bubble behaviours in wet central heating systems

    Science.gov (United States)

    Shefik, Ali; Ge, Yunting

    2014-03-01

    A series of experimental measurements has been conducted in order to investigate the bubble behaviours through the horizontal pipe line of the domestic wet central heating systems. Obtained results exposed the effect of 90 degree bend, buoyancy forces on bubbly two phase flow patterns and effect of velocity on void fractions and bubble diameters. Distance chosen for the first sight glass (HSG0) was sufficient enough to note the effect of 90 degree bend on void fraction patterns. Due to the effect of 90 degree bend, position of the peak void fractions across the pipe section lowers, with an increase in bulk fluid velocity. Bubbles tend to flow for longer distance at the bottom of the pipe section. Buoyancy force effect is demonstrated with figures for highest bulk fluid velocity at three different positions. Analysis of four different flow rates at two different saturation ratios show reduction for average bubble diameters and void fractions when bulk fluid velocity increases. An attempt to predict bubble dissolution rates across the horizontal pipeline of the system is made, however results show some uncertainties.

  8. Analysis reports on the ecotoxicological evaluation of discharges of spent water at the cogeneration/central heating plants Alloeverket, Borgaas, Haendeloeverket, Moelnlycke, Saevenaes and Aelmhult; Analysrapporter avseende ekotoxikologisk bedoemning av utslaepp av utgaaende vatten vid Alloeverket, Borgaas, Haendeloeverket, Moelnlycke, Saevenaes och Aelmhult

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Jonas; Axby, Fredrik; Persson, Maarten; Rossander, Annelie; Schultz, Emma; Svaerd, Sara [Carl Bro AB, Kristianstad (Sweden)

    2007-04-15

    The discharges to water at six biofuelled Swedish cogeneration/district heating plants are evaluated in light of the EU Water Framework Directive concerning ecotoxicological impacts. Ecotoxicological data for the 33 prioritized substances are also reviewed.

  9. Aging management guideline for commercial nuclear power plants - heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Booker, S.; Lehnert, D.; Daavettila, N.; Palop, E.

    1994-06-01

    This Aging Management Guideline (AMG) describes recommended methods for effective detection and mitigation of age-related degradation mechanisms in commercial nuclear power plant heat exchangers important to license renewal. The intent of this AMG is to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR 54. This AMG is presented in a manner that allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

  10. Comparison of multitank storage DHW heating solar plants

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.; Rossetto, L.; Schibuola, L.

    1983-04-01

    Distribution of the hot storage in a multitank system may be a suitable way to assure stratification in DHW solar heating plants of medium and great sizes. The possible connections for the various tanks are manifold: three different working ways are considered in this paper. Performances are analyzed during one year through TRNSYS computing program and the results are compared.

  11. EFFICIENCY AND LIFETIME OF SOLAR COLLECTORS FOR SOLAR HEATING PLANTS

    DEFF Research Database (Denmark)

    The 12.5 m² flat plate solar collector HT, today marketed by Arcon Solvarme A/S, has been used in solar heating plants in Scandinavia since 1983. The collector is designed to operate in a temperature interval between 40°C and 90°C. The efficiency of the collector has been strongly improved since...... it was introduced on the market. The paper will present the increase of the efficiency of the collector due to technical improvements since 1983. Further, measurements from the spring of 2009 of the efficiency of two HT collectors, which have been in operation in the solar heating plant Ottrupgaard, Skørping......, Denmark since 1994 with a constant high flow rate and in the solar heating plant Marstal, Denmark since 1996 with a variable flow rate, will be presented. The efficiencies will be compared to the efficiencies of the collectors when they were first installed in the solar heating plants. The measurements...

  12. EFFICIENCY AND LIFETIME OF SOLAR COLLECTORS FOR SOLAR HEATING PLANTS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Chen, Ziqian; Furbo, Simon;

    2009-01-01

    The 12.5 m² flat plate solar collector HT, today marketed by Arcon Solvarme A/S, has been used in solar heating plants in Scandinavia since 1983. The collector is designed to operate in a temperature interval between 40°C and 90°C. The efficiency of the collector has been strongly improved since...... it was introduced on the market. The paper will present the increase of the efficiency of the collector due to technical improvements since 1983. Further, measurements from the spring of 2009 of the efficiency of two HT collectors, which have been in operation in the solar heating plant Ottrupgaard, Skørping......, Denmark since 1994 with a constant high flow rate and in the solar heating plant Marstal, Denmark since 1996 with a variable flow rate, will be presented. The efficiencies will be compared to the efficiencies of the collectors when they were first installed in the solar heating plants. The measurements...

  13. Plant Heat Adaptation: priming in response to heat stress [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Isabel Bäurle

    2016-04-01

    Full Text Available Abiotic stress is a major threat to crop yield stability. Plants can be primed by heat stress, which enables them to subsequently survive temperatures that are lethal to a plant in the naïve state. This is a rapid response that has been known for many years and that is highly conserved across kingdoms. Interestingly, recent studies in Arabidopsis and rice show that this thermo-priming lasts for several days at normal growth temperatures and that it is an active process that is genetically separable from the priming itself. This is referred to as maintenance of acquired thermotolerance or heat stress memory. Such a memory conceivably has adaptive advantages under natural conditions, where heat stress often is chronic or recurring. In this review, I will focus on recent advances in the mechanistic understanding of heat stress memory.

  14. Central heating pipes cause unwanted heating; CV-leidingen zorgen voor ongewenste opwarming

    Energy Technology Data Exchange (ETDEWEB)

    Wessels, R. [biq-stadsontwerp, Rotterdam (Netherlands); Nuijten, O. [ISSO, Rotterdam (Netherlands)

    2011-12-15

    Research has shown that the risk of hot spots in the drinking water pipes is very high. Hot spots are, for example, caused by central heating pipes that are too close to the water pipes. The water pipes may be 25 C for a long period, thus creating the risk of legionella growth. The various disciplines need to be careful in the design stage and building stage to prevent such situations from occurring. [Dutch] Onderzoek heeft uitgewezen dat het risico op 'hotspots' in de drinkwaterleidingen erg groot is. Hotspots worden bijvoorbeeld veroorzaakt door cv-leidingen die te dicht in de buurt van waterleidingen lopen. Die waterleidingen kunnen dan langdurig warmer zijn dan 25C en daardoor gevaar opleveren voor legionellagroei. Het vereist zorg van meerdere disciplines in de ontwerpfase en de bouwfase om deze situaties te vermijden.

  15. 16 CFR Appendix I to Part 305 - Heating Performance and Cost for Central Air Conditioners

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Heating Performance and Cost for Central Air Conditioners I Appendix I to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC... Manufacturer's rated heating capacity (Btu's/hr.) Range of HSPF's Low High Single Package Units Heat...

  16. 16 CFR 305.12 - Labeling for central air conditioners, heat pumps, and furnaces.

    Science.gov (United States)

    2010-01-01

    ... pumps, and furnaces. (a) Layout. All energy labels for central air conditioners, heat pumps, and... air conditioners and heat pumps. (1) Headlines and texts, as illustrated in the prototype and sample.... (ii) Each heat pump label, except as noted in paragraph (g)(4)(iii) of this section, shall contain...

  17. 75 FR 14368 - Energy Conservation Standards for Residential Central Air Conditioners and Heat Pumps: Public...

    Science.gov (United States)

    2010-03-25

    ... and heat pumps; the analytical framework, models, and tools that DOE is using to evaluate amended... Heat Pumps, EERE-2008-BT- STD-0006, 1000 Independence Avenue, SW., Washington, DC 20585-0121. Telephone... industrial equipment, including residential central air conditioners and heat pumps. (42 U.S.C. 6292(3))...

  18. Transient analysis of a molten salt central receiver (MSCR) in a solar power plant

    Science.gov (United States)

    Joshi, A.; Wang, C.; Akinjiola, O.; Lou, X.; Neuschaefer, C.; Quinn, J.

    2016-05-01

    Alstom is developing solar power tower plants utilizing molten salt as the working fluid. In solar power tower, the molten salt central receiver (MSCR) atop of the tower is constructed of banks of tubes arranged in panels creating a heat transfer surface exposed to the solar irradiation from the heliostat field. The molten salt heat transfer fluid (HTF), in this case 60/40%wt NaNO3-KNO3, flows in serpentine flow through the surface collecting sensible heat thus raising the HTF temperature from 290°C to 565°C. The hot molten salt is stored and dispatched to produce superheated steam in a steam generator, which in turn produces electricity in the steam turbine generator. The MSCR based power plant with a thermal energy storage system (TESS) is a fully dispatchable renewable power plant with a number of opportunities for operational and economic optimization. This paper presents operation and controls challenges to the MSCR and the overall power plant, and the use of dynamic model computer simulation based transient analyses applied to molten salt based solar thermal power plant. This study presents the evaluation of the current MSCR design, using a dynamic model, with emphasis on severe events affecting critical process response, such as MS temperature deviations, and recommend MSCR control design improvements based on the results. Cloud events are the scope of the transient analysis presented in this paper. The paper presents results from a comparative study to examine impacts or effects on key process variables related to controls and operation of the MSCR plant.

  19. Dynamic disturbance rejection controllers for neutral time delay systems with application to a central heating system

    Institute of Scientific and Technical Information of China (English)

    KOUMBOULIS Fotis N.; KOUVAKAS Nikolaos D.; PARASKEVOPOULOS Paraskevas N.

    2009-01-01

    In the present paper the problem of disturbance rejection of single input-single output neutral time delay systems with multiple measurable disturbances is solved via dynamic controllers. In particular, the general form of the controller matrices is presented, while the necessary and sufficient conditions for the controller to be realizable are offered. The proposed technique is applied to a test case neutral time delay central heating system. In particular, the nonlinear model of the plant and its linearized approximation are presented. Based on the linearized model, a two-stage controller is designed in order to regulate the room temperature and the boiler effluent temperature. The performance of the closed loop system is investigated through computational experiments.

  20. Large Combined Heat and Power Plants for Sustainable Energy System

    DEFF Research Database (Denmark)

    Lund, Rasmus Søgaard; Mathiesen, Brian Vad

    An energy supply based on 100% renewable energy in Denmark is the official goal for the Danish energy policy towards 2050. A smart energy system should be developed to integrate as much supply from fluctuating renewable sources and to utilise the scarce biomass resources as efficiently as possible....... CHP (combined heat and power) plants in Denmark will change their role from base load production to balancing the fluctuation in renewable energy supply, such as wind power and at the same time they have to change to renewable energy sources. Some solutions are already being planned by utilities...... in Denmark; conversion of pulverised fuel plants from coal to wood pellets and a circulating fluidised bed (CFB) plant for wood chips. From scientific research projects another solution is suggested as the most feasible; the combined cycle gas turbine (CCGT) plant. In this study a four scenarios...

  1. Heat Transfer and Latent Heat Storage in Inorganic Molten Salts for Concentrating Solar Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Mathur, Anoop [Terrafore Inc.

    2013-08-14

    A key technological issue facing the success of future Concentrating Solar Thermal Power (CSP) plants is creating an economical Thermal Energy Storage (TES) system. Current TES systems use either sensible heat in fluids such as oil, or molten salts, or use thermal stratification in a dual-media consisting of a solid and a heat-transfer fluid. However, utilizing the heat of fusion in inorganic molten salt mixtures in addition to sensible heat , as in a Phase change material (PCM)-based TES, can significantly increase the energy density of storage requiring less salt and smaller containers. A major issue that is preventing the commercial use of PCM-based TES is that it is difficult to discharge the latent heat stored in the PCM melt. This is because when heat is extracted, the melt solidifies onto the heat exchanger surface decreasing the heat transfer. Even a few millimeters of thickness of solid material on heat transfer surface results in a large drop in heat transfer due to the low thermal conductivity of solid PCM. Thus, to maintain the desired heat rate, the heat exchange area must be large which increases cost. This project demonstrated that the heat transfer coefficient can be increase ten-fold by using forced convection by pumping a hyper-eutectic salt mixture over specially coated heat exchanger tubes. However,only 15% of the latent heat is used against a goal of 40% resulting in a projected cost savings of only 17% against a goal of 30%. Based on the failure mode effect analysis and experience with pumping salt at near freezing point significant care must be used during operation which can increase the operating costs. Therefore, we conclude the savings are marginal to justify using this concept for PCM-TES over a two-tank TES. The report documents the specialty coatings, the composition and morphology of hypereutectic salt mixtures and the results from the experiment conducted with the active heat exchanger along with the lessons learnt during

  2. Small-Scale Combined Heat and Power Plants Using Biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Salomon-Popa, Marianne [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Energy Technology

    2002-11-01

    In this time period where energy supply and climate change are of special concern, biomass-based fuels have attracted much interest due to their plentiful supply and favorable environmental characteristics (if properly managed). The effective capture and continued sustainability of this renewable resource requires a new generation of biomass power plants with high fuel energy conversion. At the same time, deregulation of the electricity market offers new opportunities for small-scale power plants in a decentralized scheme. These two important factors have opened up possibilities for small-scale combined heat and power (CHP) plants based on biofuels. The objective of this pre-study is to assess the possibilities and technical limitations for increased efficiency and energy utilization of biofuels in small size plants (approximately 10 MWe or lower). Various energy conversion technologies are considered and proven concepts for large-scale fossil fuel plants are an especially important area. An analysis has been made to identify the problems, technical limitations and different possibilities as recognized in the literature. Beyond published results, a qualitative survey was conducted to gain first-hand, current knowledge from experts in the field. At best, the survey results together with the results of personal interviews and a workshop on the role of small-scale plants in distributed generation will serve a guideline for future project directions and ideas. Conventional and novel technologies are included in the survey such as Stirling engines, combustion engines, gas turbines, steam turbines, steam motors, fuel cells and other novel technologies/cycles for biofuels. State-of-the-art heat and power plants will be identified to clarify of the advantages and disadvantages as well as possible obstacles for their implementation.

  3. Heat-inducible RNAi for gene functional analysis in plants.

    Science.gov (United States)

    Masclaux, Frédéric; Galaud, Jean-Philippe

    2011-01-01

    Controlling gene expression during plant development is an efficient method to explore gene function and RNA interference (RNAi) is now considered as a powerful technology for gene functional analysis. However, constitutive gene silencing cannot be used with genes involved in fundamental processes such as embryo viability or plant growth and alternative silencing strategies avoiding these limitations should be preferred. Tissue-specific and inducible promoters, able to control gene expression at spatial and/or temporal level, can be used to circumvent viability problems. In this chapter, after a rapid overview of the inducible promoters currently used for transgenic approaches in plants, we describe a method we have developed to study gene function by heat-inducible RNAi. This system is easy to use and complementary to those based on chemical gene inducer treatments and might be useful for both research and biotechnological applications.

  4. Evaluation of a sulfur oxide chemical heat storage process for a steam solar electric plant

    Energy Technology Data Exchange (ETDEWEB)

    Dayan, J.; Lynn, S.; Foss, A.

    1979-07-01

    The purpose of this study was to develop and evaluate technically feasible process configurations for the use of the sulfur oxide system, 2 SO/sub 3/ reversible 2 SO/sub 2/ + O/sub 2/, in energy storage. The storage system is coupled with a conventional steam-cycle power plant. Heat for both the power plant and the storage system is supplied during sunlit hours by a field of heliostats focussed on a central solar receiver. When sunlight is not available, the storage system supplies the heat to operate the power plant. A technically feasible, relatively efficient configuration is proposed for incorporating this type of energy storage system into a solar power plant. Complete material and energy balances are presented for a base case that represents a middle range of expected operating conditions. Equipment sizes and costs were estimated for the base case to obtain an approximate value for the cost of the electricity that would be produced from such an installation. In addition, the sensitivity of the efficiency of the system to variations in design and operating conditions was determined for the most important parameters and design details. In the base case the solar tower receives heat at a net rate of 230 MW(t) for a period of eight hours. Daytime electricity is about 30 MW(e). Nighttime generation is at a rate of about 15 MW(e) for a period of sixteen hours. The overall efficiency of converting heat into electricity is about 26%. The total capital cost for the base case is estimated at about $68 million, of which about 67% is for the tower and heliostats, 11% is for the daytime power plant, and 22% is for the storage system. The average cost of the electricity produced for the base case is estimated to be about 11 cents/kW(e)-hr.

  5. Shrines in Central Italy conserve plant diversity and large trees.

    Science.gov (United States)

    Frascaroli, Fabrizio; Bhagwat, Shonil; Guarino, Riccardo; Chiarucci, Alessandro; Schmid, Bernhard

    2016-05-01

    Sacred natural sites (SNS) are instances of biocultural landscapes protected for spiritual motives. These sites frequently host important biological values in areas of Asia and Africa, where traditional resource management is still upheld by local communities. In contrast, the biodiversity value of SNS has hardly been quantitatively tested in Western contexts, where customs and traditions have relatively lost importance due to modernization and secularization. To assess whether SNS in Western contexts retain value for biodiversity, we studied plant species composition at 30 SNS in Central Italy and compared them with a paired set of similar but not sacred reference sites. We demonstrate that SNS are important for conserving stands of large trees and habitat heterogeneity across different land-cover types. Further, SNS harbor higher plant species richness and a more valuable plant species pool, and significantly contribute to diversity at the landscape scale. We suggest that these patterns are related not only to pre-existent features, but also to traditional management. Conservation of SNS should take into account these specificities, and their cultural as well as biological values, by supporting the continuation of traditional management practices.

  6. ENERGY STAR Certified Non-AHRI Central Air Conditioner Equipment and Air Source Heat Pump

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 5.0 ENERGY STAR Program Requirements for Air Source Heat Pump and Central Air Conditioner...

  7. Power contracting between two different partners. Biogas combined heat and power plants; Energie-Contracting zweier unterschiedlicher Partner. Biogas-Blockheizkraftwerk

    Energy Technology Data Exchange (ETDEWEB)

    Lennartz, Marc Wilhelm

    2013-06-15

    An agricultural consortium in the Eifel (Federal Republic of Germany) has adopted a comprehensive supply of a 7,000 m{sup 2} comprising hotel complex with combined heat and power. The old oil-fired central heating plant has been replaced by a biogas-powered combined heat and power plant (CHP). The hotel was directly connected to the CHP plant by means of a new, approximately 300 m long local heating network including buffer storage. Overall, the hotel operator saves approximately 300,000 L of heating oil annually. The energy demand of the hotel operator will be covered by more than 90 % by means of CHP plants. Thus 20 % of the heating costs is saved.

  8. New integrated gas turbine CHP (combined heat and power) and incinerator plant.

    Science.gov (United States)

    Briggs, R A; Yates, B

    1990-12-01

    Despite the complex nature of the project, the clients brief of a 14 month design and installation period was achieved within the approved budget of 2.5 million pounds. Early performance figures indicate that the scheme is on target to achieve the original payback of under four years. Queen Elizabeth Hospital: installation of integrated combined heat and power plant. Client: Central Birmingham Health Authority. Consulting Engineers/Project Managers: Yates, Edge and Partners. Architects: Temple Cox and Nichols. Structural Engineers: Peel and Fowler. Quantity Surveyor: West Midlands Regional Health Authority.

  9. THE PROPERTIES OF HOUSES IN TERMS OF GEOTHERMAL CENTRAL HEATING AND THE APPROACH OF DENIZLI TO GEOTHERMAL ENERGY

    Directory of Open Access Journals (Sweden)

    Halil KARAHAN

    1996-01-01

    Full Text Available Although the geothermal fluid, which is discharged into Büyük Menderes River after electric generation at Kızıldere Geothermal power plant, has been considered as a solution the air pollution problem of Denizli province, there has been no work carried out to determine the number of house, the area of house, the type of heating, coal consumption for each house, heat isolation, and centrally heated houses. The existing works includes only the applications at local places comparing to Denizli. In order to get maximum benefit from the planned project, it is necessary to collect data for Denizli and evaluate the data at the feasibility and application phases of the project. For this purpose questionnaire forms have been given to 15000 houses and offices at the different places in Denizli. The questionnaire forms were collected and the results have been evaluated and presented in graphics.

  10. First Experience from the World Largest fully commercial Solar Heating Plant

    DEFF Research Database (Denmark)

    Heller, Alfred; Furbo, Simon

    1997-01-01

    The first experience from the largest solar heating plant in the world is given. The plant is situated in Marstal and is has a total area of 8000 square m.......The first experience from the largest solar heating plant in the world is given. The plant is situated in Marstal and is has a total area of 8000 square m....

  11. Sustainability Assessment of a Self-Consumption Wood-Energy Chain on Small Scale for Heat Generation in Central Italy

    Directory of Open Access Journals (Sweden)

    Stefano Verani

    2015-06-01

    Full Text Available The sustainability of a small-scale self-consumption wood-energy chain for heat generation in central Italy was analyzed from a technical, economic and energetic point of view. A micro-chain was developed within the CRA-ING farm at Monterotondo (Rome, Italy: The purpose of this system was to produce biomass for supplying a heating plant within the CRA-ING property as a substitute for diesel fuel. A poplar short rotation coppice, established with clones AF2, AF6 and Monviso, fed the micro-chain. The rotation was biennial. The average plantation production (Mgd.m.·ha−1·year−1 was 10.2, with a maximum of 13.53 for the twin-rows AF2 and a minimum of 8.00 for the single-row Monviso. The economic assessment was based on the Net Present Value (NPV method and the equivalent annuity cost, and found an average saving of 15.60 €·GJ−1 of heat generated by the wood chips heating system in comparison with the diesel heating system over a 10 year lifetime of the thermal power plant. The energy assessment of the poplar plantation, carried out using the Gross Energy Requirements method, reported an energy output/input ratio of 12.3. The energy output/input ratio of the whole micro-chain was 4.5.

  12. Coal Gasification Processes for Retrofitting Military Central Heating Plants: Overview

    Science.gov (United States)

    1992-11-01

    inorganic material remainitig after coal is completely combusted. At high temperatures, the ash will melt and clinkers may form. The ash composition ...was employed until 1941 by more than 9000 producers worldwide. Units installed in 1933 and 1948 are currently operating in South Africa . In 1980...Springs. South Africa Vaal Potteries Ltd. 1 8.5 Bituminous Operational Meyerton, South Africa Union Steel Corporation 2 10 Bituminous Operational

  13. Central Control of Heat Pump for Smart Grid Purposes Tested on Single Family Houses

    DEFF Research Database (Denmark)

    Pedersen, Tom S.; Andersen, Palle; Nielsen, Kirsten M.

    2013-01-01

    A challenge in Denmark in the near future is to balance the electrical grid due to a large increase in the renewable energy production mainly from wind turbines. In this work a central control system using heat pumps in single family houses to help balancing the grid is investigated. The central...

  14. Performance analysis of a Kalina cycle for a central receiver solar thermal power plant with direct steam generation

    DEFF Research Database (Denmark)

    Modi, Anish; Haglind, Fredrik

    2014-01-01

    Solar thermal power plants have attracted increasing interest in the past few years - with respect to both the design of the various plant components, and extending the operation hours by employing different types of storage systems. One approach to improve the overall plant efficiency is to use...... without corroding the equipment by using suitable additives with the mixture. The purpose of the study reported here was to investigate if there is any benefit of using a Kalina cycle for a direct steam generation, central receiver solar thermal power plant with high live steam temperature (450 C...... direct steam generation with water/steam as both the heat transfer fluid in the solar receivers and the cycle working fluid. This enables operating the plant with higher turbine inlet temperatures. Available literature suggests that it is feasible to use ammonia-water mixtures at high temperatures...

  15. EFFICIENCY AND LIFETIME OF SOLAR COLLECTORS FOR SOLAR HEATING PLANTS

    OpenAIRE

    Fan, Jianhua; Chen, Ziqian; Furbo, Simon; Perers, Bengt; Karlsson, Björn

    2009-01-01

    The 12.5 m² flat plate solar collector HT, today marketed by Arcon Solvarme A/S, has been used in solar heating plants in Scandinavia since 1983. The collector is designed to operate in a temperature interval between 40°C and 90°C. The efficiency of the collector has been strongly improved since it was introduced on the market. The paper will present the increase of the efficiency of the collector due to technical improvements since 1983. Further, measurements from the spring of 2009 of the e...

  16. Large combined heat and power plants in sustainable energy systems

    DEFF Research Database (Denmark)

    Lund, Rasmus Søgaard; Mathiesen, Brian Vad

    2015-01-01

    In many countries, the electricity supply and power plant operation are challenged by increasing amounts of fluctuating renewable energy sources. A smart energy system should be developed to integrate as much energy supply from fluctuating renewable sources and to utilise the scarce biomass...... resources as efficiently as possible. Using the advanced energy systems analysis tool EnergyPLAN and Denmark as a case, this analysis defines which of the three assessed types of CHP plants connected to district heating systems is most feasible in terms of total socioeconomic costs and biomass consumption...... as an unsustainable level of biomass consumption. Therefore, the regulatory framework should generally be considered in long-term planning of sustainable CHP systems....

  17. Plants adapted to warmer climate do not outperform regional plants during a natural heat wave.

    Science.gov (United States)

    Bucharova, Anna; Durka, Walter; Hermann, Julia-Maria; Hölzel, Norbert; Michalski, Stefan; Kollmann, Johannes; Bossdorf, Oliver

    2016-06-01

    With ongoing climate change, many plant species may not be able to adapt rapidly enough, and some conservation experts are therefore considering to translocate warm-adapted ecotypes to mitigate effects of climate warming. Although this strategy, called assisted migration, is intuitively plausible, most of the support comes from models, whereas experimental evidence is so far scarce. Here we present data on multiple ecotypes of six grassland species, which we grew in four common gardens in Germany during a natural heat wave, with temperatures 1.4-2.0°C higher than the long-term means. In each garden we compared the performance of regional ecotypes with plants from a locality with long-term summer temperatures similar to what the plants experienced during the summer heat wave. We found no difference in performance between regional and warm-adapted plants in four of the six species. In two species, regional ecotypes even outperformed warm-adapted plants, despite elevated temperatures, which suggests that translocating warm-adapted ecotypes may not only lack the desired effect of increased performance but may even have negative consequences. Even if adaptation to climate plays a role, other factors involved in local adaptation, such as biotic interactions, may override it. Based on our results, we cannot advocate assisted migration as a universal tool to enhance the performance of local plant populations and communities during climate change.

  18. Modernization and efficiency of heat treatment and heating up plants; Modernisierung und Effizienz von Thermoprozessanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, Peter [LOI Thermprocess GmbH, Essen (Germany); Kuehn, Friedhelm [Ingenieurbuero fuer Waermebehandlung, Industrieoefen und Energieberatung, Muelheim (Germany)

    2010-10-15

    A goal of this contribution is to show, using examples of the thermal heat treatment industry and the thermal processing units used there (Beltype plants, routary hearth, walking hearth, walking beam, pusher type furnaces and gas carburizing plants as well as case hardening plants), which increases in efficiency within and outside of the actual thermal treatment process and the necessary thermal processing units for the order are available today. From the possibilities of the reduction of energy employment resulting from that, a high potential for the discharge of the environment can be derived. The economic effect concerning energy employment and saving possibilities will also be considered. Concluding, examples of case-hardening show which variants of a change of process present themselves partially in the future, in order to achieve substantial production increases and thus energy cost reductions. (orig.)

  19. PLANT COMMUNITIES WITH ARNICA MONTANA IN NATURAL HABITATS FROM THE CENTRAL REGION OF ROMANIAN EASTERN CARPATHIANS

    Directory of Open Access Journals (Sweden)

    Constantin MARDARI

    2015-12-01

    Full Text Available Arnica montana is a species of European Union interest, whose harvest from the wild and exploitation should be made under certain management measures. In Romania it is a vulnerable species due to excessive collection. It is a species with European areal occuring in pastures, meadows, forest glades, shrubs communities of mountain to the subalpine regions and, isolated, up to the alpine belt. Most of the plant communities with Arnica montana are semi-natural, with a floristic composition in which there are numerous rare or threatened species also supporting the need of their conservation. Our study was focused on a numerical classification (hierarchical, using Flexible ß algorithm and Bray-Curtis dissimilarity based on 48 plots, of the plant communities with Arnica montana from the central region of Romanian Eastern Carpathians and on the investigation of the effect of some environmental variables (Ellenberg indicator values, altitude, heat load index on their floristic composition (100 m2 scale. Vegetation – environment relationship was assessed via detrended correspondence analysis and canonical correspondence analysis with Monte Carlo test. Six plant communities with Arnica montana were identified (communities of Festuca rubra with Agrostis capillaris, Festuca nigrescens, Vaccinium myrtillus, Nardus stricta, Vaccinium gaultherioides and Juniperus sibirica with a floristic composition mainly shaped by altitude, temperature and soil nitrogen content. Details related to location and sites characteristics, diagnostic species, floristic composition, presence of other rare or threatened species and Arnica montana abundance were presented for all these plant communities.

  20. Absorption chillers integration in a combined heat and power plant

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, J. C.; Fernandez, F.; Castells, F. [Barcelona Univ., Tarragona (Spain). Dept. d`Enginyeria Quimica i Bioqumica

    1996-11-01

    Inclusion of an absorption cycle within a combined heat and power plant (CHP) was evaluated. To determine the most suitable configuration of the energy network generation system and absorption chiller, a simulation and optimization model was constructed. To validate the optimization model, a case study using actual data from existing operating plants has been used. In the case described the cooling facilities from the absorption cycle were used to lower the inlet temperature to the compressor of the gas turbine to improve the overall plant efficiency. Waste steam from the steam network was used in the generator of the absorption chiller. A reduction in steam wastes, and an improvement in overall plant efficiency was observed. A simulation model of a single effect absorption chiller, using water-lithium bromide as the working fluid pair, was used to validate the methodology. Results showed that the benefits of integrating the absorption refrigeration cycle (ARC) depends directly on the refrigeration demand, and on the benefit produced by the waste steam recovered. The increase in power generation, allowing a reduction in primary energy consumption, showed a slight economic advantage over the conventional compression cycle. 13 refs., 7. tabs., 6 figs.

  1. Elimination of Oscillations in a Central Heating System using Pump Control

    DEFF Research Database (Denmark)

    Andersen, Palle; Pedersen, Tom Søndergaard; Stoustrup, Jakob;

    2000-01-01

    In central heating systems with thermostatic valve temperature control it is a well known fact that room temperature oscillations may occur when the heat demand becomes low due to the non-linear behavior of the control loop. This is not only discomforting but it also increases the energy cost...... of heating the room. Using the pump speed as an active part in control is it shown that the room temperature may be stabilized in a wider interval of heat demand. The idea is to control the pump speed in a way that keeps the thermostatic valve within a suitable operating area using an estimate of the valve...... position. The position is estimated from the pump terminals, using the pump flow and the pump differential pressure. The concept is tested on a small central heating test bench. The results show that it is possible to stabilize the room temperature even at part load conditions...

  2. Is sexual reproduction of high-mountain plants endangered by heat?

    Science.gov (United States)

    Ladinig, Ursula; Pramsohler, Manuel; Bauer, Ines; Zimmermann, Sonja; Neuner, Gilbert; Wagner, Johanna

    2015-04-01

    Strong solar irradiation in combination with still air and dry soil can cause prostrate high-mountain plants to heat up considerably and ultimately suffer heat damage. Such heat damage has been repeatedly shown for vegetative structures, but not for reproductive structures, which we expected to be particularly vulnerable to heat. Heat effects on cold-adapted plants may increase with rising global temperatures and the predicted increase in heat waves. We have tested the heat tolerance of reproductive versus vegetative shoots at different reproductive stages, comparing ten common plant species from different elevation belts in the European Alps. Plant samples were exposed to temperatures in 2-K steps of 30 min each between 42 and 56 °C. Heat damage was assessed by visual rating and vital staining. Reproductive shoots were on average 2.5 K less heat tolerant (LT50, i.e. the mean temperature causing 50 % heat damage, 47.2 °C) than vegetative shoots (mean LT50 49.7 °C). Initial heat injuries (mean LT10) were observed at 43-45 °C in heat-susceptible species and at 45-47 °C in more heat-tolerant species, in at least one reproductive stage. Generally, heat tolerance was significantly higher during fruiting than during the bud stages and anthesis. Prostrate species with acaulescent buds and flowers tolerated heat better than those with caulescent buds and flowers. Petals were the most heat-susceptible plant structure and mature pollen the most heat tolerant. Based on these data, heat tolerance of reproductive structures appears to be adapted to the prevailing maximum temperatures which the plants experience during different reproductive stages in their environment. During hot spells, however, heat tolerance thresholds may be exceeded. More frequent heat waves would decrease the reproductive output and, consequently, the competitiveness of heat-susceptible species.

  3. Identification and Characterization of Proteins Associated with Plant Tolerance to Heat Stress

    Institute of Scientific and Technical Information of China (English)

    Bingru Huang; Chenping Xu

    2008-01-01

    Heat stress is a major abiotic stress limiting plant growth and productivity in many areas of the world. Understanding mechanisms of plant adaptation to heat stress would facilitate the development of heat-tolerant cultivars for improving productivity in warm climatic regions. Protein metabolism involving protein synthesis and degradation is one of the most sensitive processes to heat stress. Changes in the level and expression pattern of some proteins may play an important role in plant adaptation to heat stress. The identification of stress-responsive proteins and pathways has been facilitated by an increasing number of tools and resources, including two-dimensional electrophoresis and mass spectrometry, and the rapidly expanding nucleotide and amino acid sequence databases. Heat stress may induce or enhance protein expression or cause protein degradation. The induction of heat-responsive proteins, particularly heat shock proteins (HSPs), plays a key role in plant tolerance to heat stress. Protein degradation involving various proteases is also important in regulating plant responses to heat stress. This review provides an overview of recent research on proteomic profiling for the identification of heat-responsive proteins associated with heat tolerance, heat induction and characteristics of HSPs, and protein degradation in relation to plant responses to heat stress.

  4. Optimizing Waste Heat Recovery for Class A Biosolids Production from a Combined Cycle Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Soroushian, Fred

    2003-07-01

    The City of Corona serves a rapidly growing area of Southern California, The City operates three wastewater treatment plants (WWTPs) that produce reclaimed water for unrestricted reuse. The sludge from the three WWTPs is transported to a central sludge treatment facility located at WWTP No. 1. The sludge treatment facility consists of sludge receiving, thickening, anaerobic digestion, and dewatering. In the year 2000, the City was faced with two crises. First, the California power shortage and escalating cost of power severely impacted the industry and businesses. Second, bans on Class B biosolids land application and the shutdown of a local privatized composting facility where the bulk of the City's biosolids were processed or reused forced the City to transport bulk waste a much greater distance. To cost-effectively respond to these crises, the City decided to start generating and supplying power to its constituents by constructing a nominal 30-megawatt (MW) power plant. The feasibility study proved that locating the power plant at the City's largest WWTP produced significant synergies. The reclaimed water from the WWTP could be used for power plant cooling, the waste heat from the power plant could be recovered and used in Class A biosolids processes, the digester gas could be used for supplementing the fuel needs of the sludge dryer, and the combined facilities operation was more efficient than physically separate facilities. This paper presents the results of this analysis as well as the construction and operational aspects of the project. (author)

  5. Solar augmentation for process heat with central receiver technology

    Science.gov (United States)

    Kotzé, Johannes P.; du Toit, Philip; Bode, Sebastian J.; Larmuth, James N.; Landman, Willem A.; Gauché, Paul

    2016-05-01

    Coal fired boilers are currently one of the most widespread ways to deliver process heat to industry. John Thompson Boilers (JTB) offer industrial steam supply solutions for industry and utility scale applications in Southern Africa. Transport cost add significant cost to the coal price in locations far from the coal fields in Mpumalanga, Gauteng and Limpopo. The Helio100 project developed a low cost, self-learning, wireless heliostat technology that requires no ground preparation. This is attractive as an augmentation alternative, as it can easily be installed on any open land that a client may have available. This paper explores the techno economic feasibility of solar augmentation for JTB coal fired steam boilers by comparing the fuel savings of a generic 2MW heliostat field at various locations throughout South Africa.

  6. Host plants of the tarnished plant bug (Heteroptera: Miridae) in Central Texas.

    Science.gov (United States)

    Esquivel, J F; Mowery, S V

    2007-08-01

    The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), has taken on added importance as a pest of cotton in the Cotton Belt after successful eradication efforts for the boll weevil (Anthonomus grandis grandis Boheman). Because the Southern Blacklands region of Central Texas is in advanced stages of boll weevil eradication, blooming weeds and selected row crops were sampled during a 3-yr study to determine lygus species composition and associated temporal host plants. L. lineolaris was the sole lygus species in the region. Thirteen previously unreported host plants were identified for L. lineolaris, of which 69% supported reproduction. Rapistrum rugosum L. Allioni and Ratibida columnifera (Nuttall) Wooton and Standley were primary weed hosts during the early season (17 March to 31 May). Conyza canadensis L. Cronquist variety canadensis and Ambrosia trifida L. were primary weed hosts during the midseason (1 June to 14 August) and late-season (15 August to 30 November), respectively. Sisymbrium irio L. and Lamium amplexicaule L. sustained L. lineolaris populations during the overwintering period (1 December to 16 March). The proportion of females and numbers of nymphs found in R. rugosum, C. canadensis, A. trifida, and S. irio suggests these weeds supported reproductive adults during the early, mid-, and late season and overwintering period, respectively. Medicago sativa L. was the leading crop host for L. lineolaris; Glycine max L. Merrill did not yield L. lineolaris. Few L. lineolaris were collected in Gossypium hirsutum L. These results provide a more comprehensive assessment of host plants contributing to L. lineolaris populations in central Texas.

  7. Designing for the home: a comparative study of support aids for central heating systems.

    Science.gov (United States)

    Sauer, J; Wastell, D G; Schmeink, C

    2009-03-01

    The study examined the influence of different types of enhanced system support on user performance during the management of a central heating system. A computer-based simulation of a central heating system, called CHESS V2.0, was used to model different interface options, providing different support facilities to the user (e.g., historical, predictive, and instructional displays). Seventy-five participants took part in the study and completed a series of operational scenarios under different support conditions. The simulation environment allowed the collection of performance measures (e.g., energy consumption), information sampling, and system control behaviour. Subjective user evaluations of various aspects of the system were also measured. The results showed performance gains for predictive displays whereas no such benefits were observed for the other display types. The data also revealed that status and predictive displays were valued most highly by users. The implications of the findings for designers of central heating systems are discussed.

  8. System design package for the solar heating and cooling central data processing system

    Science.gov (United States)

    1978-01-01

    The central data processing system provides the resources required to assess the performance of solar heating and cooling systems installed at remote sites. These sites consist of residential, commercial, government, and educational types of buildings, and the solar heating and cooling systems can be hot-water, space heating, cooling, and combinations of these. The instrumentation data associated with these systems will vary according to the application and must be collected, processed, and presented in a form which supports continuity of performance evaluation across all applications. Overall software system requirements were established for use in the central integration facility which transforms raw data collected at remote sites into performance evaluation information for assessing the performance of solar heating and cooling systems.

  9. Exhaust gas side corrosion of oil fired central heating boilers

    Energy Technology Data Exchange (ETDEWEB)

    Koebel, M.; Elsener, M.

    1987-09-01

    While Swiss boiler producers aim primarily at achieving low exhaust gas temperatures, in our northern neighbouring country, lower boiler water temperatures are being set as favourite objectives to be met. The first method aims at reducing the exhaust gas losses, i.e. of the heat content of the exhaust gases; the second one aims at reducing service life losses (= losses in the off-air of the boiler). Flue-gas caused corrosion, however, sets practical limits to the energy-saving reduction of the exhaust gas and boiler water temperatures. To be able to define this practical limit more exactly is the main goal of this project which is supported by NEFF and which is carried out in cooperation with the Institute for Energy Engineering of the ETHZ (Professor P. Suter). In addition to this, however, the author also head to find out about sill inexplained cases of corrosion in boilers which are being operated correctly, i.e. with comparably high boiler water and exhaust gas temperatures.

  10. Dosimetry in nuclear power plants; Dosimetria en centrales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Lastra B, J. A. [CFE, Central Laguna Verde, Km. 42.5 Carretera Cardel-Nautla, Veracruz (Mexico)

    2008-12-15

    To control the occupationally exposed personnel dose working at the Laguna Verde nuclear power plant, two types of dosemeters are used, the thermoluminescent (TLD) which is processed monthly, and the direct reading dosemeter that is electronic and works as daily control of personal dose. In the case of the electronic dosemeters of direct reading conventional, the readings and dose automatic registers and the user identity to which he was assigned to each dosemeter was to carry out the restricted area exit. In activities where the ionizing radiation sources are not fully characterized, it is necessary to relocate the personal dosemeter or assigned auxiliary dosemeters (TLDs and electronics) to determine the dose received by the user to both whole body and in any specific area of it. In jobs more complicated are used a tele dosimetry system where the radiation protection technician can be monitoring the user dose to remote control, the data transmission is by radio. The dosimetry activities are documented in procedures that include dosemeter inventories realization, the equipment and dosemeters calibration, the dosimetry quality control and the discrepancies investigation between the direct reading and TLD systems. TLD dosimetry to have technical expertise in direct and indirect dosimetry and two technicians in TLD dosimetry; electronic dosimetry to have 4 calibration technicians. For the electronic dosemeters are based on a calibrator source of Cesium-137. TLD dosemeters to have an automatic radiator, an automatic reader which can read up to 100 TLD dosemeters per hour and a semiautomatic reader. To keep the equipment under a quality process was development a process of initial entry into service and carried out a periodic verification of the heating cycles. It also has a maintenance contract for the equipment directly with the manufacturer to ensure their proper functioning. The vision in perspective of the dosimetry services of Laguna Verde nuclear power plant

  11. An examination of heat rate improvements due to waste heat integration in an oxycombustion pulverized coal power plant

    Science.gov (United States)

    Charles, Joshua M.

    Oxyfuel, or oxycombustion, technology has been proposed as one carbon capture technology for coal-fired power plants. An oxycombustion plant would fire coal in an oxidizer consisting primarily of CO2, oxygen, and water vapor. Flue gas with high CO2 concentrations is produced and can be compressed for sequestration. Since this compression generates large amounts of heat, it was theorized that this heat could be utilized elsewhere in the plant. Process models of the oxycombustion boiler, steam cycle, and compressors were created in ASPEN Plus and Excel to test this hypothesis. Using these models, heat from compression stages was integrated to the flue gas recirculation heater, feedwater heaters, and to a fluidized bed coal dryer. All possible combinations of these heat sinks were examined, with improvements in coal flow rate, Qcoal, net power, and unit heat rate being noted. These improvements would help offset the large efficiency impacts inherent to oxycombustion technology.

  12. Remote Measurement of Heat Flux from Power Plant Cooling Lakes

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, Alfred J.; Kurzeja, Robert J.; Villa-Aleman, Eliel; Bollinger, James S.; Pendergast, Malcolm M.

    2013-06-01

    Laboratory experiments have demonstrated a correlation between the rate of heat loss q" from an experimental fluid to the air above and the standard deviation σ of the thermal variability in images of the fluid surface. These experimental results imply that q" can be derived directly from thermal imagery by computing σ. This paper analyses thermal imagery collected over two power plant cooling lakes to determine if the same relationship exists. Turbulent boundary layer theory predicts a linear relationship between q" and σ when both forced (wind driven) and free (buoyancy driven) convection are present. Datasets derived from ground- and helicopter-based imagery collections had correlation coefficients between σ and q" of 0.45 and 0.76, respectively. Values of q" computed from a function of σ and friction velocity u* derived from turbulent boundary layer theory had higher correlations with measured values of q" (0.84 and 0.89). Finally, this research may be applicable to the problem of calculating losses of heat from the ocean to the atmosphere during high-latitude cold-air outbreaks because it does not require the information typically needed to compute sensible, evaporative, and thermal radiation energy losses to the atmosphere.

  13. Thermodynamic Analysis of a Ship Power Plant Operating with Waste Heat Recovery through Combined Heat and Power Production

    Directory of Open Access Journals (Sweden)

    Mirko Grljušić

    2014-11-01

    Full Text Available The goal of this research is to study a cogeneration plant for combined heat & power (CHP production that utilises the low-temperature waste energy in the power plant of a Suezmax-size oil tanker for all heating and electricity requirements during navigation. After considering various configurations, a standard propulsion engine operating at maximum efficiency and a CHP Plant with R245fa fluid using a supercritical organic Rankine cycle (ORC is selected. All the ship heat requirements can be covered by energy of organic fluid after expansion in the turbine, except feeder-booster heating. Hence, an additional quantity of working fluid may be heated using an after Heat Recovery Steam Generator (HRSG directed to the feeder-booster module. An analysis of the obtained results shows that the steam turbine plant does not yield significant fuel savings. However, a CHP plant with R245fa fluid using supercritical ORC meets all of the demands for electrical energy and heat while burning only a small amount of additional fuel in HRSG at the main engine off-design operation.

  14. Developing a strategy for improving efficiency in the heating sector in central and eastern Europe

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, A.S. [World Bank, Washington, DC (United States)

    1995-12-31

    Heating is a vital energy service in Central and Eastern Europe, but the current delivery mechanisms are riddled with problems. District heating (DH) in its present technical form and with the present management structures is an inefficient system which produces expensive heat. Customers cannot control it and react to overheating by opening windows, even in winter. DH facilities together with other forms of individual heating are responsible for air pollution, causing severe impacts on the health of urban residents. The issues relating to DH are discussed, the first World Bank activities and experiences with projects in Poland are analyzed, and the cornerstones of a strategy to support future World Bank financing and the development of sound heating policies in CEE are presented.

  15. Effective ways to modernize outdated coal heat power plants

    Science.gov (United States)

    Suchkov, S. I.; Kotler, V. R.; Batorshin, V. A.

    2016-12-01

    An analysis of the state of equipment of 72 outdated coal HPP (heat power plants) of a total capacity 14.3 GW with steam parameters before the turbines p before ≤ 9 MPa, t before = 420-540°C was performed. The equipment is characterized by a considerably low efficiency factor, even if it were converted to burning the natural gas, and by increased release of harmful substances. However, on the most part of the considered HPP, the steam turbines, unlike the boilers, have thus far retained the operation applicability and satisfactory reliability of performance. The analysis has shown that it makes sense to effectively modernize the outdated coal HPP by transformation of their equipment into combined-cycle plant (CCP) with coal gasification, which has high economic and ecological indicators due to thermodynamic advantage of the combined cycle and simpler purification of the generator gas in the process under pressure. As the most rational way of this transformation, the one was recognized wherein—instead of the existing boiler (boilers) or parallel to it—a gasification and gas turbine system is installed with a boiler-utilizer (BU), from which steam is fed to the HPP main steam pipe. In doing this, the basic part of the power station equipment persists. In the world, this kind of reconstruction of steam power equipment is applied widely and successfully, but it is by use of natural gas for the most part. It is reasonable to use the technology developed at Heat Engineering Research Institute (HERI) of hearth-steam gasification of coal and high-temperature purification of the generator gas. The basic scheme and measures on implementation of this method for modernization of outdated coal HPP is creation of CCP with blast-furnace of coal on the basis of accessible and preserved HPP equipment. CCP power is 120 MW, input-output ratio (roughly) 44%, emissions of hazardous substances are 5 mg/MJ dust, 20-60 mg/MJ SO2, and 50-100 mg/MJ NO x . A considerable decrease of

  16. [Heat-responsive mechanisms in plants revealed by proteomic analysis: A review].

    Science.gov (United States)

    Liu, Jun-ming; Zhao, Qi; Yin, Ze-peng; Xu, Chen-xi; Wang, Quan-hua; Dai, Shao-jun

    2015-08-01

    Heat stress is a major abiotic stress that limits plant growth and productivity. In recent years, proteomic investigations provide more information for understanding the sophisticated heat-responsive molecular mechanism in plants at systematic biological level. The heat-responsive proteomic patterns in several plants, i. e., model plants (Arabidopsis thaliana), staple food crops (soybean, rice and wheat), heat-tolerant plants (Agrostis stolonifera, Portulaca oleracea, and Carissa spinarum), grapevine, Populus euphratica, Medicago sativa, and Pinellia ternate, were reported. A total of 838 heat-responsive proteins have been identified in these studies. Among them, 534 proteins were induced and the expression of 304 proteins was reduced in plants under heat stress. In this paper, the diverse protein patterns in plants under various heat stress conditions (30-45 °C for 0-10 d) were analyzed integratively. This provided new evidences and clues for further interpreting the signaling and metabolic pathways, e.g., signaling, stress and defense, carbohydrate and energy metabolism, photosynthesis, transcription, protein synthesis and fate, membrane and transport, in heat-responsive networks, and laid a foundation for a holistic understanding of the molecular regulatory mechanism in plants in response to heat stress.

  17. Climate change scenarios of heat waves in Central Europe and their uncertainties

    Science.gov (United States)

    Lhotka, Ondřej; Kyselý, Jan; Farda, Aleš

    2017-01-01

    The study examines climate change scenarios of Central European heat waves with a focus on related uncertainties in a large ensemble of regional climate model (RCM) simulations from the EURO-CORDEX and ENSEMBLES projects. Historical runs (1970-1999) driven by global climate models (GCMs) are evaluated against the E-OBS gridded data set in the first step. Although the RCMs are found to reproduce the frequency of heat waves quite well, those RCMs with the coarser grid (25 and 50 km) considerably overestimate the frequency of severe heat waves. This deficiency is improved in higher-resolution (12.5 km) EURO-CORDEX RCMs. In the near future (2020-2049), heat waves are projected to be nearly twice as frequent in comparison to the modelled historical period, and the increase is even larger for severe heat waves. Uncertainty originates mainly from the selection of RCMs and GCMs because the increase is similar for all concentration scenarios. For the late twenty-first century (2070-2099), a substantial increase in heat wave frequencies is projected, the magnitude of which depends mainly upon concentration scenario. Three to four heat waves per summer are projected in this period (compared to less than one in the recent climate), and severe heat waves are likely to become a regular phenomenon. This increment is primarily driven by a positive shift of temperature distribution, but changes in its scale and enhanced temporal autocorrelation of temperature also contribute to the projected increase in heat wave frequencies.

  18. Advective heat transport associated with regional Earth degassing in central Apennine (Italy)

    Science.gov (United States)

    Chiodini, G.; Cardellini, C.; Caliro, S.; Chiarabba, C.; Frondini, F.

    2013-07-01

    In this work we show that the main springs of the central Apennine transport a total amount of heat of ˜2.2×109 J s-1. Most of this heat (57%) is the result of geothermal warming while the remaining 43% is due to gravitational potential energy dissipation. This result indicates that a large area of the central Apennines is very hot with heat flux values >300 mW m-2. These values are higher than those measured in the magmatic and famously geothermal provinces of Tuscany and Latium and about 1/3 of the total heat discharged at Yellowstone. This finding is surprising because the central Apennines have been thought to be a relatively cold area. Translated by CO2 rich fluids, this heat anomaly suggests the existence of a thermal source such as a large magmatic intrusion at depth. Recent tomographic images of the area support the presence of such an intrusion visible as a broad negative velocity anomaly in seismic waves. Our results indicate that the thermal regime of tectonically active areas of the Earth, where meteoric waters infiltrate and deeply circulate, should be revised on the basis of mass and energy balances of the groundwater systems.

  19. Preliminary design review package for the solar heating and cooling central data processing system

    Energy Technology Data Exchange (ETDEWEB)

    1976-05-25

    This preliminary design review package, consisting of the Software Performance Specification, Hardware Performance Specification, and the Verification Plan for the Central Data Processing System (CDPS), was prepared by the IBM Corporation. The Central Data Processing System, located at IBM's FSD facility in Huntsville, Alabama, provides the resources required to assess the performance of solar heating and cooling systems at remote sites. These sites include residential, commercial, government, and educational types of buildings, and the solar heating and cooling systems can be hot water, space heating, cooling, and combinations of these. The instrumentation data associated with these systems will vary according to the application and must be collected, processed, and presented in a form which supports continuity of performance evaluation across all applications.

  20. System design package for the solar heating and cooling central data processing system

    Energy Technology Data Exchange (ETDEWEB)

    1978-03-01

    This system design package for the Central Data Processing System consists of the Software Performance Specification, Hardware Performance Specification, Software Verification Plan, CDPS Development Program, Qualification and Acceptance Test Procedures, Qualification Test and Analysis Report, and Qualification and Acceptance Test Review. The Central Data Processing System, located at IBM's Federal System Division facility in Huntsville, Alabama, provides the resources required to assess the performance of solar heating and cooling systems installed at remote sites. These sites consist of residential, commercial, government, and educational types of buildings, and the solar heating and cooling systems can be hot-water, space heating, cooling, and combinations of these. The instrumentation data associated with these systems will vary according to the application and must be collected, processed, and presented in a form which supports continuity of performance evaluation across all applications.

  1. Power generation plant integrating concentrated solar power receiver and pressurized heat exchanger

    Science.gov (United States)

    Sakadjian, Bartev B; Flynn, Thomas J; Hu, Shengteng; Velazquez-Vargas, Luis G; Maryamchik, Mikhail

    2016-10-04

    A power plant includes a solar receiver heating solid particles, a standpipe receiving solid particles from the solar receiver, a pressurized heat exchanger heating working fluid by heat transfer through direct contact with heated solid particles flowing out of the bottom of the standpipe, and a flow path for solid particles from the bottom of the standpipe into the pressurized heat exchanger that is sealed by a pressure P produced at the bottom of the standpipe by a column of heated solid particles of height H. The flow path may include a silo or surge tank comprising a pressure vessel connected to the bottom of the standpipe, and a non-mechanical valve. The power plant may further include a turbine driven by heated working fluid discharged from the pressurized heat exchanger, and a compressor driven by the turbine.

  2. Preliminary design of the Carrisa Plains solar central receiver power plant. Volume III, Book 2. Design drawings

    Energy Technology Data Exchange (ETDEWEB)

    1983-12-31

    The design of the 30 MWe central receiver solar power plant to be located at Carrisa Plains, San Luis Obispo County, California, is summarized. The plant uses a vertical flat-panel (billboard) solar receiver located at the top of a tower to collect solar energy redirected by approximately 1900 heliostats located to the north of the tower. The solar energy is used to heat liquid sodium pumped from ground level from 610 to 1050/sup 0/F. The power conversion system is a non-reheat system, cost-effective at this size level, and designed for high-efficiency performance in an application requiring daily startup. Successful completion of this project will lead to power generation starting in 1986. This report consists of design drawings for this plant.

  3. Romania's experience in using woody residues as a combustible for central heating; L'experience roumaine de l'utilisation des residus ligneux comme combustible pour le chauffage central

    Energy Technology Data Exchange (ETDEWEB)

    Lavrov, G. [Inst. des Etudes et des Projets Energetiques (Romania)

    2004-06-01

    Romania's national policy for renewable resources promotes the use of clean and renewable energy. The national policy is intended to increase the national contribution of renewable energy sources and to develop non-conventional technologies for exploiting renewable resources. This paper described two examples where woody residues are used as a combustible for central heating. The first example describes a local industry in Campeni, a village of 10,000 people located near the Aires River, which produces 54,000 tons of ligneous waste each year. A central heating plant was modernized to accept this waste as a fuel. Two old boilers were replaced with two modern, Romanian-made boilers that produce a calorific output of 8,790 kJ/kg. The efficiency of the new boilers is 83 per cent. The benefits of this modernization have been a significant reduction in pollution of the Aires River by reducing the number of ligneous waste dumped into the river. Carbon dioxide and SOx emissions have also been reduced by replacing fossil fuel with biomass. The thermal comfort of the buildings served by the heating plant has also improved because the new boilers produce 88 per cent more heat. The second example focuses on the village of Tasca in Moldavia, a forest rich region of Romania where the wood dust from local saw mills has polluted the Bicaz and Damuc Rivers. A project was launched to develop an urban district heating system by installing a new 2.5 MW boiler fueled by sawdust and ligneous waste. Consumers were connected to the thermal energy distribution system. A separate system was created to collect waste from the sawmills. The benefits of this project have been a significant reduction in the pollution of the rivers, increased comfort levels in houses and a significant reduction in air pollution because the old individual and inefficient heating systems were replaced with an efficient central heating system. 1 tab.

  4. EFFICIENCY OF THE USE OF HEAT PUMPS ON THE CHP PLANTS

    Directory of Open Access Journals (Sweden)

    Juravleov A.A.

    2007-04-01

    Full Text Available The work is dedicated to the calculus of the efficiency of the use of heat pumps on the CHP plants. There are presented the interdependences between the pay-back period and NPV of heat pump and the price of 1 kWt of thermal power of heat pump and of the tariff of electricity.

  5. Earthquake-proof plants; Centrales a prueba de terremotos

    Energy Technology Data Exchange (ETDEWEB)

    Francescutti, P.

    2008-07-01

    In the wake of the damage suffered by the Kashiwazaki-Kariwa nuclear power plant as a result of an earthquake last July, this article looks at the seismic risk affecting the Spanish plants and the safety measures in place to prevent it. (Author)

  6. Temperature stress differentially modulates transcription in meiotic anthers of heat-tolerant and heat-sensitive tomato plants

    Directory of Open Access Journals (Sweden)

    Pezzotti Mario

    2011-07-01

    Full Text Available Abstract Background Fluctuations in temperature occur naturally during plant growth and reproduction. However, in the hot summers this variation may become stressful and damaging for the molecular mechanisms involved in proper cell growth, impairing thus plant development and particularly fruit-set in many crop plants. Tolerance to such a stress can be achieved by constitutive gene expression or by rapid changes in gene expression, which ultimately leads to protection against thermal damage. We have used cDNA-AFLP and microarray analyses to compare the early response of the tomato meiotic anther transcriptome to moderate heat stress conditions (32°C in a heat-tolerant and a heat-sensitive tomato genotype. In the light of the expected global temperature increases, elucidating such protective mechanisms and identifying candidate tolerance genes can be used to improve breeding strategies for crop tolerance to heat stress. Results The cDNA-AFLP analysis shows that 30 h of moderate heat stress (MHS alter the expression of approximately 1% of the studied transcript-derived fragments in a heat-sensitive genotype. The major effect is gene down-regulation after the first 2 h of stress. The microarray analysis subsequently applied to elucidate early responses of a heat-tolerant and a heat-sensitive tomato genotype, also shows about 1% of the genes having significant changes in expression after the 2 h of stress. The tolerant genotype not only reacts with moderate transcriptomic changes but also exhibits constitutively higher expression levels of genes involved in protection and thermotolerance. Conclusion In contrast to the heat-sensitive genotype, the heat-tolerant genotype exhibits moderate transcriptional changes under moderate heat stress. Moreover, the heat-tolerant genotype also shows a different constitutive gene expression profile compared to the heat-sensitive genotype, indicating genetic differences in adaptation to increased temperatures. In

  7. Methods for planning and operating decentralized combined heat and power plants

    Energy Technology Data Exchange (ETDEWEB)

    Palsson, H.

    2000-02-01

    In recent years, the number of decentralized combined heat and power (DCHP) plants, which are typically located in small communities, has grown rapidly. These relatively small plants are based on Danish energy resources, mainly natural gas, and constitute an increasing part of the total energy production in Denmark. The topic of this thesis is the analysis of DCHP plants, with the purpose to optimize the operation of such plants. This involves the modelling of district heating systems, which are frequently connected to DCHP plants, as well as the use of heat storage for balancing between heat and power production. Furthermore, the accumulated effect from increasing number of DCHP plants on the total power production is considered. Methods for calculating dynamic temperature response in district heating (DH) pipes have been reviewed and analyzed numerically. Furthermore, it has been shown that a tree-structured DH network consisting of about one thousand pipes can be reduced to a simple chain structure of ten equivalent pipes without loosing much accuracy when temperature dynamics are calculated. A computationally efficient optimization method based on stochastic dynamic programming has been designed to find an optimum start-stop strategy for a DCHP plant with a heat storage. The method focuses on how to utilize heat storage in connection with CHP production. A model for the total power production in Eastern Denmark has been applied to the accumulated DCHP production. Probability production simulations have been extended from the traditional power-only analysis to include one or several heat supply areas. (au)

  8. THE NITROGEN OXIDE CONCENTRATION DEPENDENCE ON HEAT LOSSES WITH EXIT SMOKE GASES OF HEAT-GENERATING PLANTS

    Directory of Open Access Journals (Sweden)

    A. A. Sedaev

    2012-04-01

    Full Text Available Problem statement. The most significant heat losses are losses associated with exit gases. It is these losses that determine the scale of heat emissions into the plant air with fuel combustion products and reduce the environmental safety of the plant. Many of the derived methods for reducing the nitrogen oxide emission associated with gas purification systems provide a high degree of smoke gas purification, but these methods are based on the use of various chemicals, which sharply reduces their environmental and operational characteristics.Results. The suggested method of simultaneous purification and recycling of gaseous emissions of heat-generating plants differs profitably from the existing ones. Its application will improve tech-nical and economic and also environmental characteristics of heat-generating plants and will make the characteristics of the energy enterprise a closer match to those of waste-free, environmentally-friendly and profitable enterprises.Conclusions. The obtained results confirm the fact that reduction of heat losses with exit gases re-sults in a reduction of nitrogen oxide emissions. Therefore, an increase in environmental safety of a boiler unit can be achieved in tandem with one in heat efficiency.

  9. Preliminary design of the Carrisa Plains solar central receiver power plant. Volume III, Book 1. Design description

    Energy Technology Data Exchange (ETDEWEB)

    1983-12-31

    The design of the 30 MWe central receiver solar power plant to be located at Carrisa Plains, San Luis Obispo County, California, is summarized. The plant uses a vertical flat-panel (billboard solar receiver located at the top of a tower to collect solar energy redirected by approximately 1900 heliostats located to the north of the tower. The solar energy is used to heat liquid sodium pumped from ground level from 610 to 1050/sup 0/F. The power conversion system is a non-reheat system, cost-effective at this size level, and designed for high-efficiency performance in an application requiring daily startup. Successful completion of this project will lead to power generation starting in 1986. This report discusses in detail the design of the collector system, heat transport system, thermal storage subsystem, heat transport loop, steam generation subsystem, electrical, instrumentation, and control systems, power conversion system, master control system, and balance of plant. The performance, facility cost estimate and economic analysis, and development plan are also discussed.

  10. Heat supply from municipal solid waste incineration plants in Japan: Current situation and future challenges.

    Science.gov (United States)

    Tabata, Tomohiro; Tsai, Peii

    2016-02-01

    The use of waste-to-energy technology as part of a municipal solid waste management strategy could reduce the use of fossil fuels and contribute to prevention of global warming. In this study, we examined current heat and electricity production by incineration plants in Japan for external use. Herein, we discuss specific challenges to the promotion of heat utilisation and future municipal solid waste management strategies. We conducted a questionnaire survey to determine the actual conditions of heat production by incineration plants. From the survey results, information of about 498 incineration plants was extracted. When we investigated the relationship between heat production for external use and population density where incineration plants were located, we found that regions with a population density heat. We also found that external use of such energy for factories, markets, and related use, was noted in cities with a population density of 2000 to 4000 persons (km(2))(-1). Several incineration plants have poor performance for heat production because there are few facilities near them to provide demand for the energy. This is the result of redundant capacity, and is reflected in the heat production performance. Given these results, we discussed future challenges to creating energy demand around incineration plants where there is presently none. We also examined the challenges involved in increasing heat supply beyond the present situation.

  11. Calculation and Designing of Up-to-Date Gas-Flame Plants for Metal Heating and Heat Treatment

    Directory of Open Access Journals (Sweden)

    V. I. Тimoshpolsky

    2008-01-01

    Full Text Available An analysis of development trends in the CIS machine-building industry and current status of the heating and heat treatment furnaces of main machine-building enterprises of the Republic of Belarus as of the 1st quarter of 2008 is given in the paper.The paper presents the most efficient engineering solutions from technological and economic point of view that concern calculation and designing of up-to-date gas-flame plants which are to be applied for modernization of the current heating and heat treatment furnaces of the machine-building enterprises in the Republic of Belarus.A thermo-technical calculation of main indices of the up-to-date gas-flame plant has been carried out in the paper.

  12. Puertollano IGCC Power Plant; Central de Gasificacion Integrada en Ciclo Combinado de Puertollano

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The Puertollano IGCC Power Plant, rated 335 MW and located in Puertollano, Ciudad Real, in the central area of Spain, is a project led by ELCOGAS, a company incorporated by the European utilities ENDESA, ELECTRICITE DE FRANCE, IBERDROLA HIDROCANTABRICO ELECTRICIDADE DE PURTUGAL, ENEL and NATIONAL POWER and the technology and equipment suppliers SIEMENS, KRUPP UHDE and BABCOCK WILCOX ESPANOLA. IGCC technology is based in a process of coal gasification to obtain a clean combustion synthetic gas, integrated with a combined cycle, agas and steam, electricity-generating unit. The energy efficiency which is aimed to achieve at the Plant is 46% in ISO conditions. The Gasification unit uses the process of pressurised entrained flow for coal gasification. The gas is produced by the reaction of coal with oxygen at high temperatures, of up to 1600 degree centigree. This process is capable of gasifying a wide variety of types and qualities of coal for the production of a synthetic fuel gas. In the case of Puertollano, the raw fuel is a 50% mixture by weight of local coal and petroleum coke. The oxygen needed in the process and the nitrogen used for covering the fuel is generated in the Air Separation. The Gas Cleaning and Sulphur Recovery Unit clean the gases from contaminants and solid particles before to send them to the Gas Turbine. The clean gas is burnt in gas turbine of the Combined Cycle Plant, producing electricity. The exhaust gases feed a heat recovery steam generator, which produces steam used to generate additional electricity in a conventional steam turbine. The gas turbine is capable of operating both with synthetic gas and with natural gas, allowing operation flexibility. The net output of the plant up to December 1999 was 3.061 GWh, from them 344 GWh were produced with synthetic gas. This project has an important technological value, being the first power plant which uses coal gasification to feed a combined cycle in Spain and being also the biggest power plant

  13. Solar Pilot Plant, Phase I. Preliminary design report. Volume II, Book 2. Central receiver optical model users manual. CDRL item 2. [HELIAKI code

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-05-01

    HELIAKI is a FORTRAN computer program which simulates the optical/thermal performance of a central receiver solar thermal power plant for the dynamic conversion of solar-generated heat to electricity. The solar power plant which this program simulates consists of a field of individual sun tracking mirror units, or heliostats, redirecting sunlight into a cavity, called the receiver, mounted atop a tower. The program calculates the power retained by that cavity receiver at any point in time or the energy into the receiver over a year's time using a Monte Carlo ray trace technique to solve the multiple integral equations. An artist's concept of this plant is shown.

  14. Operation and Maintenance Manual for the Central Facilities Area Sewage Treatment Plant

    Energy Technology Data Exchange (ETDEWEB)

    Norm Stanley

    2011-02-01

    This Operation and Maintenance Manual lists operator and management responsibilities, permit standards, general operating procedures, maintenance requirements and monitoring methods for the Sewage Treatment Plant at the Central Facilities Area at the Idaho National Laboratory. The manual is required by the Municipal Wastewater Reuse Permit (LA-000141-03) the sewage treatment plant.

  15. Codigestion of manure and industrial organic waste at centralized biogas plants: process imbalances and limitations

    DEFF Research Database (Denmark)

    Bangsø Nielsen, Henrik; Angelidaki, Irini

    2008-01-01

    The present study focuses on process imbalances in Danish centralized biogas plants treating manure in combination with industrial waste. Collection of process data from various full-scale plants along with a number of interviews showed that imbalances occur frequently. High concentrations...

  16. ENERGY STAR Certified Non-AHRI Central Air Conditioner Equipment and Air Source Heat Pump

    Science.gov (United States)

    Certified models meet all ENERGY STAR requirements as listed in the Version 5.0 ENERGY STAR Program Requirements for Air Source Heat Pump and Central Air Conditioner Equipment that are effective as of September 15, 2015. A detailed listing of key efficiency criteria are available at http://www.energystar.gov/index.cfm?c=airsrc_heat.pr_crit_as_heat_pumps Listed products have been submitted to EPA by ENERGY STAR partners that do not participate in the AHRI certification program. EPA will continue to update this list with products that are certified by EPA-recognized certification bodies other than AHRI. The majority of ENERGY STAR products, certified by AHRI, can be found on the CEE/AHRI Verified Directory at http://www.ceedirectory.org/

  17. Operation Performance of Central Solar Heating System with Seasonal Storage Water Tank in Harbin

    Institute of Scientific and Technical Information of China (English)

    YE Ling; JIANG Yi-qiang; YAO Yang; ZHANG Shi-cong

    2009-01-01

    This paper presented a preliminary research on the central solar heating system with seasonal stor-age(CSHSSS)used in cold climate in China.A mathematical model of the solar energy seasonal storage water tank used in the central solar heating system was firstly developed based on energy conservation.This was fol-lowed by the simulation of the CSHSSS used in a two-floor villa in Harbin,and analysis of the impacts on storage water temperature of tank volume,solar collector area,tank burial depth,insulation thickness around the tank,etc.The results show there is a relatively economical tank volume to optimize the system efficiency,which de-creases with increasing tank volume at the constant collector area,and increases with increasing collector area at the constant tank volume.Furthermore,the insulation thickness has obvious effect on avoiding heat loss,while the tank burial depth doesn't.In addition-the relationship between the solar collector efficiency and storage wa-ter temperature is also obtained,it decreases quickly with increasing storing water temperature,and then in-creases slowly after starting space heating system.These may be helpful for relevant design and optimization in cold climates in China and all over the world.

  18. Report of results of benchmarking survey of central heating operations at NASA centers and various corporations

    Science.gov (United States)

    Hoffman, Thomas R.

    1995-01-01

    In recent years, Total Quality Management has swept across the country. Many companies and the Government have started looking at every aspect on how business is done and how money is spent. The idea or goal is to provide a service that is better, faster and cheaper. The first step in this process is to document or measure the process or operation as it stands now. For Lewis Research Center, this report is the first step in the analysis of heating plant operations. This report establishes the original benchmark that can be referred to in the future. The report also provides a comparison to other organization's heating plants to help in the brainstorming of new ideas. The next step is to propose and implement changes that would meet the goals as mentioned above. After the changes have been implemented the measuring process starts over again. This provides for a continuous improvement process.

  19. Remote and Centralized Monitoring of PV Power Plants

    DEFF Research Database (Denmark)

    Kopacz, Csaba; Spataru, Sergiu; Sera, Dezso

    2014-01-01

    the inverters within each PV plant. The monitoring software stores the PV measurements in a data warehouse optimized for managing and data mining large amounts of data, from where it can be later visualized, analyzed and exported. By combining PV production measurements data with I-V curve measurements...

  20. Assessment of heat shock protein 70 induction by heat in alfalfa varieties and constitutive overexpression in transgenic plants.

    Directory of Open Access Journals (Sweden)

    Nicoletta Ferradini

    Full Text Available Heat shock proteins (HSPs are molecular chaperones involved in many cellular functions. It has been shown that mammalian cytosolic HSP70 binds antigenic peptides mediating the activation of the immune system, and that it plays a determining role in tumour immunogenicity. This suggests that HSP70 may be used for the production of conjugated vaccines. Human and plant HSPs share high sequence similarity and some important biological functions in vitro. In addition, plant HSPs have no endotoxic side effects. Extraction of HSP70 from plants for use as vaccine adjuvant requires enhancing its concentration in plant tissues. In this work, we explored the possibility to produce HSP70 in both transgenic and non-transgenic plants, using alfalfa as a model species. First, a transcriptional analysis of a constitutive and an inducible HSP70 genes was conducted in Arabidopsis thaliana. Then the coding sequence of the inducible form was cloned and introduced into alfalfa by Agrobacterium-mediated transformation, and the accumulation of the protein in leaf tissue of transgenic plants was demonstrated. We also tested diverse alfalfa varieties for heat-inducible expression of endogenous HSP70, revealing variety-specific responses to heat shock.

  1. Diversity of the Mountain Flora of Central Asia with Emphasis on Alkaloid-Producing Plants

    Directory of Open Access Journals (Sweden)

    Karimjan Tayjanov

    2017-02-01

    Full Text Available The mountains of Central Asia with 70 large and small mountain ranges represent species-rich plant biodiversity hotspots. Major mountains include Saur, Tarbagatai, Dzungarian Alatau, Tien Shan, Pamir-Alai and Kopet Dag. Because a range of altitudinal belts exists, the region is characterized by high biological diversity at ecosystem, species and population levels. In addition, the contact between Asian and Mediterranean flora in Central Asia has created unique plant communities. More than 8100 plant species have been recorded for the territory of Central Asia; about 5000–6000 of them grow in the mountains. The aim of this review is to summarize all the available data from 1930 to date on alkaloid-containing plants of the Central Asian mountains. In Saur 301 of a total of 661 species, in Tarbagatai 487 out of 1195, in Dzungarian Alatau 699 out of 1080, in Tien Shan 1177 out of 3251, in Pamir-Alai 1165 out of 3422 and in Kopet Dag 438 out of 1942 species produce alkaloids. The review also tabulates the individual alkaloids which were detected in the plants from the Central Asian mountains. Quite a large number of the mountain plants produce neurotoxic and cytotoxic alkaloids, indicating that a strong chemical defense is needed under the adverse environmental conditions of these mountains with presumably high pressure from herbivores.

  2. Experience with the operation of a solar central heating system in Friedrichshafen/Wiggenhausen-Sued; Betriebserfahrungen mit der solaren Nahwaermeversorgung in Friedrichshafen/Wiggenhausen-Sued

    Energy Technology Data Exchange (ETDEWEB)

    Stanzel, B.; Gawantka, F. [Technische Werke Friedrichshafen GmbH, Friedrichshafen (Germany)

    1998-12-31

    The ideas, concepts and pilot plants for solar central heating systems developed by the Institute for Thermodynamics and Thermal Engineering of Stuttgart University were implemented by the Steinbeis-Transfer Centre for Energy, Building and Solar Engineering. In order to improve the economic efficiency of solar central heating with long-term storage a pilot plant with a heat storage tank of 12,000 cubic metres was built in Wiggenhausen-Sued. The `Technische Werke Friedrichshafen` (TWF) is in charge of the project `Solar City Wiggenhausen-Sued`. This company built the plant and also operates and maintains it. (orig.) [Deutsch] Die Ideen, Konzepte und erste Pilotanlagen zur solaren Nahwaerme werden seit Mitte der achtziger Jahre vom Institut fuer Thermodynamik und Waermetechnik (ITW) der Universitaet Stuttgart entwickelt und vom Steinbeis-Transferzentrum Energie-, Gebaeude- und Solartechnik umgesetzt. Um die solare Nahwaermeversorgung mit Langzeit-Waermespeicher der Wirtschaftlichkeit etwas naeher zu bringen, wurde eine Pilotanlage mit einem 12.000 m{sup 3} grossen Waermespeicher in Wiggenhausen-Sued gebaut. Mit diesem Pilotprojekt soll neben der technischen Durchfuehrbarkeit die Kostendegression durch steigende Anlagengroesse nachgewiesen werden. Als Energiedienstleistungsunternehmen hat die Technische Werke Friedrichshafen GmbH (TWF) die technische und kaufmaennische Durchfuehrung des Projektes `Solarstadt Wiggenhausen-Sued` uebernommen. Sie errichtete, betreibt und wartet die Anlage. (orig.)

  3. A new perspective on the 1930s mega-heat waves across central United States

    Science.gov (United States)

    Cowan, Tim; Hegerl, Gabi

    2016-04-01

    The unprecedented hot and dry conditions that plagued contiguous United States during the 1930s caused widespread devastation for many local communities and severely dented the emerging economy. The heat extremes experienced during the aptly named Dust Bowl decade were not isolated incidences, but part of a tendency towards warm summers over the central United States in the early 1930s, and peaked in the boreal summer 1936. Using high-quality daily maximum and minimum temperature observations from more than 880 Global Historical Climate Network stations across the United States and southern Canada, we assess the record breaking heat waves in the 1930s Dust Bowl decade. A comparison is made to more recent heat waves that have occurred during the latter half of the 20th century (i.e., in a warming world), both averaged over selected years and across decades. We further test the ability of coupled climate models to simulate mega-heat waves (i.e. most extreme events) across the United States in a pre-industrial climate without the impact of any long-term anthropogenic warming. Well-established heat wave metrics based on the temperature percentile threshold exceedances over three or more consecutive days are used to describe variations in the frequency, duration, amplitude and timing of the events. Casual factors such as drought severity/soil moisture deficits in the lead up to the heat waves (interannual), as well as the concurrent synoptic conditions (interdiurnal) and variability in Pacific and Atlantic sea surface temperatures (decadal) are also investigated. Results suggest that while each heat wave summer in the 1930s exhibited quite unique characteristics in terms of their timing, duration, amplitude, and regional clustering, a common factor in the Dust Bowl decade was the high number of consecutive dry seasons, as measured by drought indicators such as the Palmer Drought Severity and Standardised Precipitation indices, that preceded the mega-heat waves. This

  4. Economic and environmental efficiency of district heating plants

    DEFF Research Database (Denmark)

    Agrell, Per J.; Bogetoft, Peter

    2005-01-01

    heat, have arbitrary valuation.This study concerns the most developed European district heating and cogeneration system, the Danish.By assessing environmental and economic ef¿ciency, the impact of governmental, market and managerial imperfections are estimated.The principal methodological base...

  5. Calibration of Discrete Element Heat Transfer Parameters by Central Composite Design

    Science.gov (United States)

    Deng, Zongquan; Cui, Jinsheng; Hou, Xuyan; Jiang, Shengyuan

    2017-03-01

    The efficiency and precision of parameter calibration in discrete element method (DEM) are not satisfactory, and parameter calibration for granular heat transfer is rarely involved. Accordingly, parameter calibration for granular heat transfer with the DEM is studied. The heat transfer in granular assemblies is simulated with DEM, and the effective thermal conductivity (ETC) of these granular assemblies is measured with the transient method in simulations. The measurement testbed is designed to test the ETC of the granular assemblies under normal pressure and a vacuum based on the steady method. Central composite design (CCD) is used to simulate the impact of the DEM parameters on the ETC of granular assemblies, and the heat transfer parameters are calibrated and compared with experimental data. The results show that, within the scope of the considered parameters, the ETC of the granular assemblies increases with an increasing particle thermal conductivity and decreases with an increasing particle shear modulus and particle diameter. The particle thermal conductivity has the greatest impact on the ETC of granular assemblies followed by the particle shear modulus and then the particle diameter. The calibration results show good agreement with the experimental results. The error is less than 4%, which is within a reasonable range for the scope of the CCD parameters. The proposed research provides high efficiency and high accuracy parameter calibration for granular heat transfer in DEM.

  6. Wood pellet heating plants. Market survey. 4. upd. ed.; Hackschnitzel-Heizung. Marktuebersicht

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-15

    Wood pellets from the agriculture and forestry offer an enormous potential for the development of the use of bio energy in the private area as well as in industry and commerce. Within the market survey 'Wood pellet heating systems', the Fachagentur Nachwachsende Rohstoffe e.V. (Guelzow-Pruezen, Federal Republic of Germany) reported on the targets and measures of the Federal Government with respect to the heating with biomass, wood pellets as solid biofuels (standardization of solid biofuels, supply, features, evaluation), wood pellet heating plants, economic considerations, market survey on wood pellet heating plants as well as list of addresses for producers of wood pellet heating plants and suppliers of wood pellets.

  7. Role and regulation of autophagy in heat stress responses of tomato plants.

    Science.gov (United States)

    Zhou, Jie; Wang, Jian; Yu, Jing-Quan; Chen, Zhixiang

    2014-01-01

    As sessile organisms, plants are constantly exposed to a wide spectrum of stress conditions such as high temperature, which causes protein misfolding. Misfolded proteins are highly toxic and must be efficiently removed to reduce cellular proteotoxic stress if restoration of native conformations is unsuccessful. Although selective autophagy is known to function in protein quality control by targeting degradation of misfolded and potentially toxic proteins, its role and regulation in heat stress responses have not been analyzed in crop plants. In the present study, we found that heat stress induced expression of autophagy-related (ATG) genes and accumulation of autophagosomes in tomato plants. Virus-induced gene silencing (VIGS) of tomato ATG5 and ATG7 genes resulted in increased sensitivity of tomato plants to heat stress based on both increased development of heat stress symptoms and compromised photosynthetic parameters of heat-stressed leaf tissues. Silencing of tomato homologs for the selective autophagy receptor NBR1, which targets ubiquitinated protein aggregates, also compromised tomato heat tolerance. To better understand the regulation of heat-induced autophagy, we found that silencing of tomato ATG5, ATG7, or NBR1 compromised heat-induced expression of not only the targeted genes but also other autophagy-related genes. Furthermore, we identified two tomato genes encoding proteins highly homologous to Arabidopsis WRKY33 transcription factor, which has been previously shown to interact physically with an autophagy protein. Silencing of tomato WRKY33 genes compromised tomato heat tolerance and reduced heat-induced ATG gene expression and autophagosome accumulation. Based on these results, we propose that heat-induced autophagy in tomato is subject to cooperative regulation by both WRKY33 and ATG proteins and plays a critical role in tomato heat tolerance, mostly likely through selective removal of heat-induced protein aggregates.

  8. Role and Regulation of Autophagy in Heat Stress Responses of Tomato Plants

    Directory of Open Access Journals (Sweden)

    Jie eZhou

    2014-04-01

    Full Text Available As sessile organisms, plants are constantly exposed to a wide spectrum of stress conditions such as high temperature, which causes protein misfolding. Misfolded proteins are highly toxic and must be efficiently removed to reduce cellular proteotoxic stress if restoration of native conformations is unsuccessful. Although selective autophagy is known to function in protein quality control by targeting degradation of misfolded and potentially toxic proteins, its role and regulation in heat stress responses have not been analyzed in crop plants. In the present study, we found that heat stress induced expression of autophagy-related (ATG genes and accumulation of autophagosomes in tomato plants. Virus-induced gene silencing of tomato ATG5 and ATG7 genes resulted in increased sensitivity of tomato plants to heat stress based on both increased development of heat stress symptoms and compromised photosynthetic parameters of heat-stressed leaf tissues. Silencing of tomato homologs for the selective autophagy receptor NBR1, which targets ubiquitinated protein aggregates, also compromised tomato heat tolerance. To better understand the regulation of heat-induced autophagy, we found that silencing of tomato ATG5, ATG7 or NBR1 compromised heat-induced expression of not only the targeted genes but also other autophagy-related genes. Furthermore, we identified two tomato genes encoding proteins highly homologous to Arabidopsis WRKY33 transcription factor, which has been previously shown to interact physically with an autophagy protein. Silencing of tomato WRKY33 genes compromised tomato heat tolerance and reduced heat-induced ATG gene expression and autophagosome accumulation. Based on these results, we propose that heat-induced autophagy in tomato is subject to cooperative regulation by both WRKY33 and ATG proteins and plays a critical role in tomato heat tolerance, mostly likely through selective removal of heat-induced protein aggregates.

  9. Calculation of Efficiencies of a Ship Power Plant Operating with Waste Heat Recovery through Combined Heat and Power Production

    Directory of Open Access Journals (Sweden)

    Mirko Grljušić

    2015-05-01

    Full Text Available The aim of this research was to investigate the possibility of a combined heat & power (CHP plant, using the waste heat from a Suezmax-size oil tanker’s main engine, to meet all heating and electricity requirements during navigation. After considering various configurations, a standard propulsion engine operating at maximum efficiency, combined with a supercritical Organic Rankine cycle (ORC system, was selected to supply the auxiliary power, using R245fa or R123 as the working fluid. The system analysis showed that such a plant can meet all heat and electrical power requirements at full load, with the need to burn only a small amount of supplementary fuel in a heat recovery steam generator (HRSG when the main engine operates at part load. Therefore, it is possible to increase the overall thermal efficiency of the ship’s power plant by more than 5% when the main engine operates at 65% or more of its specified maximum continuous rating (SMCR.

  10. Application and design of an economizer for waste heat recovery in a cogeneration plant

    Directory of Open Access Journals (Sweden)

    Martić Igor I.

    2016-01-01

    Full Text Available Energy increase cost has required its more effective use. However, many industrial heating processes generate waste energy. Use of waste-heat recovery systems decreases energy consumption. This paper presents case study of waste heat recovering of the exhaust flue gas in a 1415 kWe cogeneration plant. This waste heat can be recovered by installing an economizer to heat the condensed and fresh water in thermal degasification unit and reduce steam use for maintaining the temperature of 105˚C for oxygen removal. Design methodology of economizer is presented.

  11. The Plant Heat Stress Transcription Factors (HSFs): Structure, Regulation, and Function in Response to Abiotic Stresses.

    Science.gov (United States)

    Guo, Meng; Liu, Jin-Hong; Ma, Xiao; Luo, De-Xu; Gong, Zhen-Hui; Lu, Ming-Hui

    2016-01-01

    Abiotic stresses such as high temperature, salinity, and drought adversely affect the survival, growth, and reproduction of plants. Plants respond to such unfavorable changes through developmental, physiological, and biochemical ways, and these responses require expression of stress-responsive genes, which are regulated by a network of transcription factors (TFs), including heat stress transcription factors (HSFs). HSFs play a crucial role in plants response to several abiotic stresses by regulating the expression of stress-responsive genes, such as heat shock proteins (Hsps). In this review, we describe the conserved structure of plant HSFs, the identification of HSF gene families from various plant species, their expression profiling under abiotic stress conditions, regulation at different levels and function in abiotic stresses. Despite plant HSFs share highly conserved structure, their remarkable diversification across plants reflects their numerous functions as well as their integration into the complex stress signaling and response networks, which can be employed in crop improvement strategies via biotechnological intervention.

  12. The plant heat stress transcription factors (HSFs: structure, regulation and function in response to abiotic stresses

    Directory of Open Access Journals (Sweden)

    Meng eGuo

    2016-02-01

    Full Text Available Abiotic stresses such as high temperature, salinity and drought adversely affect the survival, growth and reproduction of plants. Plants respond to such unfavorable changes through developmental, physiological and biochemical ways, and these responses require expression of stress-responsive genes, which are regulated by a network of transcription factors (TFs, including heat stress transcription factors (HSFs. HSFs play a crucial role in plants response to several abiotic stresses by regulating the expression of stress-responsive genes, such as heat shock proteins (Hsps. In this review, we describe the conserved structure of plant HSFs, the identification of HSF gene families from various plant species, their expression profiling under abiotic stress conditions, regulation at different levels and function in abiotic stresses. Despite plant HSFs share highly conserved structure, their remarkable diversification across plants reflects their numerous functions as well as their integration into the complex stress signaling and response networks, which can be employed in crop improvement strategies via biotechnological intervention.

  13. First experience gained with heat-pump utilization in animal-husbandry plants

    Energy Technology Data Exchange (ETDEWEB)

    Kuemmritz, W.; Schaeffel, W.

    1982-10-01

    For cleaning and desinfection of all milk-conducting plant parts, the LPG Tierproduktion at the town of Berlstedt (capacity of 2000 animal stands) needs a daily amount of c. 60 cbm of heated water. Recently 50% of this useful-water requirement has been covered by four small-size heat pumps WW 12 of a water/water configuration. In the heating house, two heat pumps have been installed on top of each other in each case. The circuit plan of the heat-pump facility is demonstrated. The facility operates at open and closed loop, contains two-step rotary pumps and heats useful water to 50-60/sup 0/C. Two heat pumps are operated via shift water throughout the year, the remaining two use brook water in summer and well water in winter as their heat source. 40 t of fuel oil were saved in 1981.

  14. Enhanced biogas recovery by applying post-digestion in large-scale centralized biogas plants

    DEFF Research Database (Denmark)

    Angelidaki, Irini; Hejnfelt, Anette; Ellegaard, L.

    2006-01-01

    The main objective of this study was to investigate the degradation efficiency of centralized biogas plants and provide guidance for the design of more efficient digester and post-digestion systems. These centralized biogas plants in Denmark digest manure together with organic waste from the food...... industry to generate biogas, which is used for electricity and thermal energy. A total of 20 such plants are currently active in Denmark, most of which were included in the investigation. From the plants, samples were obtained from various steps of the process. Samples were analysed and the residual biogas...... potential determined by batch post-digestion at various temperature levels. Results were correlated with plant characteristics and production statistics in order to judge the efficiency of various digestion concepts. A simplified model based on a two-step biogas production process was developed...

  15. RESTful M2M Gateway for Remote Wireless Monitoring for District Central Heating Networks

    Directory of Open Access Journals (Sweden)

    Bo Cheng

    2014-11-01

    Full Text Available In recent years, the increased interest in energy conservation and environmental protection, combined with the development of modern communication and computer technology, has resulted in the replacement of distributed heating by central heating in urban areas. This paper proposes a Representational State Transfer (REST Machine-to-Machine (M2M gateway for wireless remote monitoring for a district central heating network. In particular, we focus on the resource-oriented RESTful M2M gateway architecture, and present an uniform devices abstraction approach based on Open Service Gateway Initiative (OSGi technology, and implement the resource mapping mechanism between resource address mapping mechanism between RESTful resources and the physical sensor devices, and present the buffer queue combined with polling method to implement the data scheduling and Quality of Service (QoS guarantee, and also give the RESTful M2M gateway open service Application Programming Interface (API set. The performance has been measured and analyzed. Finally, the conclusions and future work are presented.

  16. Performance improvement of a 330MWe power plant by flue gas heat recovery system

    Directory of Open Access Journals (Sweden)

    Xu Changchun

    2016-01-01

    Full Text Available In a utility boiler, the most heat loss is from the exhaust flue gas. In order to reduce the exhaust flue gas temperature and further boost the plant efficiency, an improved indirect flue gas heat recovery system and an additional economizer system are proposed. The waste heat of flue gas is used for high-pressure condensate regeneration heating. This reduces high pressure steam extraction from steam turbine and more power is generated. The waste heat recovery of flue gas decreases coal consumption. Other approaches for heat recovery of flue gas, direct utilization of flue gas energy and indirect flue gas heat recovery system, are also considered in this work. The proposed systems coupled with a reference 330MWe power plant are simulated using equivalent enthalpy drop method. The results show that the additional economizer scheme has the best performance. When the exhaust flue gas temperature decreases from 153℃ to 123℃, power output increases by 6.37MWe and increment in plant efficiency is about 1.89%. For the improved indirect flue gas heat recovery system, power output increases by 5.68MWe and the increment in plant efficiency is 1.69%.

  17. Preliminary design of the Carrisa Plains solar central receiver power plant. Volume II. Plant specifications

    Energy Technology Data Exchange (ETDEWEB)

    Price, R. E.

    1983-12-31

    The specifications and design criteria for all plant systems and subsystems used in developing the preliminary design of Carrisa Plains 30-MWe Solar Plant are contained in this volume. The specifications have been organized according to plant systems and levels. The levels are arranged in tiers. Starting at the top tier and proceeding down, the specification levels are the plant, system, subsystem, components, and fabrication. A tab number, listed in the index, has been assigned each document to facilitate document location.

  18. Nitrogen Removal Efficiency at Centralized Domestic Wastewater Treatment Plants in Bangkok, Thailand

    Directory of Open Access Journals (Sweden)

    Pongsak Noophan

    2009-07-01

    Full Text Available In this study, influents and effluents from centralized domestic wastewater treatment systems in Bangkok (Rattanakosin, Dindaeng, Chongnonsi, Nongkhaem, and Jatujak were randomly collected in order to measure organic nitrogen plus ammonium-nitrogen (total Kjeldahl nitrogen, total organic carbon, total suspended solids, and total volatile suspended solids by using Standard Methods for the Examination of Water and Wastewater 1998. Characteristics of influent and effluent (primary data of the centralized domestic wastewater treatment system from the Drainage and Sewerage Department of Bangkok Metropolitan Administration were used to analyze efficiency of systems. Fluorescent in situ hybridization (FISH was used to identify specific nitrifying bacteria (ammonium oxidizing bacteria specific for Nitrosomonas spp. and nitrite oxidizing bacteria specific for Nitrobacter spp. and Nitrospira spp.. Although Nitrosomonas spp. and Nitrobacter spp. were found, Nitrospira spp. was most prevalent in the aeration tank of centralized wastewater treatment systems. Almost all of the centralized domestic wastewater treatment plants in Bangkok are designed for activated sludge type biological nutrient removal (BNR. However, low efficiency nitrogen removal was found at centralized wastewater treatment plants in Bangkok. Influent ratio of TOC:N at centralized treatment plant is less than 2.5. Centralized wastewater treatment systems have not always been used suitability and used successfully in some areas of Bangkok Thailand.

  19. Mapping regional distribution of land surface heat fluxes on the southern side of the central Himalayas using TESEBS

    Science.gov (United States)

    Amatya, Pukar Man; Ma, Yaoming; Han, Cunbo; Wang, Binbin; Devkota, Lochan Prasad

    2016-05-01

    Recent scientific studies based on large-scale climate model have highlighted the importance of the heat release from the southern side of the Himalayas for the development of South Asian Summer Monsoon. However, studies related to land surface heat fluxes are nonexistent on the southern side. In this study, we test the feasibility of deriving land surface heat fluxes on the central Himalayan region using Topographically Enhanced Surface Energy Balance System (TESEBS), which is forced by MODIS land surface products and Global Land Data Assimilation System (GLDAS) meteorological data. The model results were validated using the first eddy covariance measurement system established in the southern side of the central Himalayas. The derived land surface heat fluxes were close to the field measurements with mean bias of 15.97, -19.89, 8.79, and -20.39 W m-2 for net radiation flux, ground heat flux, sensible heat flux, and latent heat flux respectively. Land surface heat fluxes show strong contrast in pre monsoon, summer monsoon, post monsoon, and winter seasons and different land surface states among the different physiographic regions. In the central Himalayas, the latent heat flux is the dominant consumer of available energy for all physiographic regions except for the High Himalaya where the sensible heat flux is high.

  20. Effects of Autumn and Spring Heat Waves on Seed Germination of High Mountain Plants.

    Science.gov (United States)

    Orsenigo, Simone; Abeli, Thomas; Rossi, Graziano; Bonasoni, Paolo; Pasquaretta, Cristian; Gandini, Maurizia; Mondoni, Andrea

    2015-01-01

    Alpine plants are considered to be particularly vulnerable to climate change and related extreme episodes, such as heat waves. Despite growing interest in the impact of heat waves on alpine plants, knowledge about their effects on regeneration is still fragmentary. Recruitment from seeds will be crucial for the successful migration and survival of these species and will play a key role in their future adaptation to climate change. In this study, we assessed the impacts of heat waves on the seed germination of 53 high mountain plants from the Northern Apennines (Italy). The seeds were exposed to laboratory simulations of three seasonal temperature treatments, derived from real data recorded at a meteorological station near the species growing site, which included two heat wave episodes that occurred both in spring 2003 and in autumn 2011. Moreover, to consider the effect of increasing drought conditions related to heat waves, seed germination was also investigated under four different water potentials. In the absence of heat waves, seed germination mainly occurred in spring, after seeds had experienced autumn and winter seasons. However, heat waves resulted in a significant increase of spring germination in c. 30% of the species and elicited autumn germination in 50%. When heat waves were coupled with drought, seed germination decreased in all species, but did not stop completely. Our results suggest that in the future, heat waves will affect the germination phenology of alpine plants, especially conditionally dormant and strictly cold-adapted chorotypes, by shifting the emergence time from spring to autumn and by increasing the proportion of emerged seedlings. The detrimental effects of heat waves on recruitment success is less likely to be due to the inhibition of seed germination per se, but rather due to seedling survival in seasons, and temperature and water conditions that they are not used to experiencing. Changes in the proportion and timing of emergence

  1. Theoretical Design of Thermosyphon for Process Heat Transfer from NGNP to Hydrogen Plant

    Energy Technology Data Exchange (ETDEWEB)

    Piyush Sabharwall; Mike Patterson; Fred Gunnerson

    2008-09-01

    The Next Generation Nuclear Plant (NGNP) will most likely produce electricity and process heat, with both being considered for hydrogen production. To capture nuclear process heat, and transport it to a distant industrial facility requires a high temperature system of heat exchangers, pumps and/or compressors. The heat transfer system is particularly challenging not only due to the elevated temperatures (up to ~ 1300K) and industrial scale power transport (=50 MW), but also due to a potentially large separation distance between the nuclear and industrial plants (100+m) dictated by safety and licensing mandates. The work reported here is the preliminary analysis of two-phase thermosyphon heat transfer performance with alkali metals. A thermosyphon is a device for transporting heat from one point to another with quite extraordinary properties. In contrast to single-phased forced convective heat transfer via ‘pumping a fluid’, a thermosyphon (also called a wickless heat pipe) transfers heat through the vaporization / condensing process. The condensate is further returned to the hot source by gravity, i.e. without any requirement of pumps or compressors. With this mode of heat transfer, the thermosyphon has the capability to transport heat at high rates over appreciable distances, virtually isothermally and without any requirement for external pumping devices. Two-phase heat transfer by a thermosyphon has the advantage of high enthalpy transport that includes the sensible heat of the liquid, the latent heat of vaporization, and vapor superheat. In contrast, single-phase forced convection transports only the sensible heat of the fluid. Additionally, vapor-phase velocities within a thermosyphon are much greater than single-phase liquid velocities within a forced convective loop. Thermosyphon performance can be limited by the sonic limit (choking) or vapor flow and/or by condensate entrainment. Proper thermosyphon requires analysis of both.

  2. Failure of steam line causes determined by NDT testing in power and heating plants

    Directory of Open Access Journals (Sweden)

    Srdjan Bulatovic

    2013-10-01

    Full Text Available This paper examines leakage and damages of steam and provides an overview of NDT testing in order to determine the cause of steam lines failure in power plants and heating plants. This approach may be applied to similar structures and its application in preventive maintenance would help extend the life of steam pipes.

  3. Development of a solar thermal central heat receiver using molten salt

    Science.gov (United States)

    Tracey, T. R.

    1981-06-01

    The development and test of a 5 MWth solar heat receiver using a molten nitrate salt (60 percent NaNO3, 40 percent KNaNO3) as the heat transfer fluid is described. The application of the receiver concept in a central receiver solar power system is explained. The advantages of using molten nitrate salts as the receiver heat transfer fluid and the storage fluid are discussed. The problems associated with the receiver development including the need for high temperatures and combinations of creep and fatigue in the receiver tubes are discussed. Our approach to scaling from the 5 MWth test receiver to commercial receivers in the range of 200 MWth to 500 MWth is defined. The 5 MWth test system is described including the instrumentation used. The test facility which has a 60 m tower and 222 heliostats is described. The test results are presented. The receiver was in test for 500 hr at temperature and heat flux levels expected in commercial receiver systems.

  4. The central role of heat shock factor 1 in synaptic fidelity and memory consolidation.

    Science.gov (United States)

    Hooper, Philip L; Durham, Heather D; Török, Zsolt; Hooper, Paul L; Crul, Tim; Vígh, László

    2016-09-01

    Networks of neuronal synapses are the fundamental basis for making and retaining memory. Reduced synapse number and quality correlates with loss of memory in dementia. Heat shock factor 1 (HSF1), the major transcription factor regulating expression of heat shock genes, plays a central role in proteostasis, in establishing and sustaining synaptic fidelity and function, and in memory consolidation. Support for this thesis is based on these observations: (1) heat shock induces improvements in synapse integrity and memory consolidation; (2) synaptic depolarization activates HSF1; (3) activation of HSF1 alone (independent of the canonical heat shock response) augments formation of essential synaptic elements-neuroligands, vesicle transport, synaptic scaffolding proteins, lipid rafts, synaptic spines, and axodendritic synapses; (4) HSF1 coalesces and activates memory receptors in the post-synaptic dendritic spine; (5) huntingtin or α-synuclein accumulation lowers HSF1 while HSF1 lowers huntingtin and α-synuclein aggregation-a potential vicious cycle; and (6) HSF1 agonists (including physical activity) can improve cognitive function in dementia models. Thus, via direct gene expression of synaptic elements, production of HSPs that assure high protein fidelity, and activation of other neuroprotective signaling pathways, HSF1 agonists could provide breakthrough therapy for dementia-associated disease.

  5. Threatened plant species of the Nevada Test Site, Ash Meadows, central-southern Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Beatley, J.C.

    1977-04-01

    This report is a companion one to Endangered Plant Species of the Nevada Test Site, Ash Meadows, and Central-Southern Nevada (COO-2307-11) and deals with the threatened plant species of the same area. The species are those cited in the Federal Register, July 1, 1975, and include certain ones listed as occurring only in California or Arizona, but which occur also in central-southern Nevada. As with the earlier report, the purpose of this one is to record in detail the location of the past plant collections which constitute the sole or principal basis for defining the species' distributions and frequency of occurrence in southern Nye County, Nevada, and to recommend the area of the critical habitat where this is appropriate. Many of the species occur also in southern California, and for these the central-southern Nevada records are presented for consideration of the overall status of the species throughout its range.

  6. Building America Case Study: Multifamily Central Heat Pump Water Heaters, Davis, California

    Energy Technology Data Exchange (ETDEWEB)

    2017-03-08

    Although heat pump water heaters (HPWHs) have gained significant attention in recent years as a high efficiency electric water heating solution for single family homes, central HPWHs for commercial or multi-family applications are not as well documented in terms of measured performance and cost effectiveness. To evaluate this technology, the Alliance for Residential Building Innovation team monitored the performance of a 10.5 ton central HPWH installed on a student apartment building at the West Village Zero Net Energy Community in Davis, California. Monitoring data collected over a 16-month period were then used to validate a TRNSYS simulation model. The TRNSYS model was then used to project performance in different climates using local electric rates. Results of the study indicate that after some initial commissioning issues, the HPWH operated reliably with an annual average efficiency of 2.12 (Coefficient of Performance). The observed efficiency was lower than the unit's rated efficiency, primarily due to the fact that the system rarely operated under steady-state conditions. Changes in the system configuration, storage tank sizing, and control settings would likely improve the observed field efficiency. Modeling results suggest significant energy savings relative to electric storage water heating systems (typical annual efficiencies around 0.90) providing for typical simple paybacks of six to ten years without any incentives. The economics versus gas water heating are currently much more challenging given the current low natural gas prices in much of the country. Increased market size for this technology would benefit cost effectiveness and spur greater technology innovation.

  7. How a retrotransposon exploits the plant's heat stress response for its activation.

    Directory of Open Access Journals (Sweden)

    Vladimir V Cavrak

    2014-01-01

    Full Text Available Retrotransposons are major components of plant and animal genomes. They amplify by reverse transcription and reintegration into the host genome but their activity is usually epigenetically silenced. In plants, genomic copies of retrotransposons are typically associated with repressive chromatin modifications installed and maintained by RNA-directed DNA methylation. To escape this tight control, retrotransposons employ various strategies to avoid epigenetic silencing. Here we describe the mechanism developed by ONSEN, an LTR-copia type retrotransposon in Arabidopsis thaliana. ONSEN has acquired a heat-responsive element recognized by plant-derived heat stress defense factors, resulting in transcription and production of full length extrachromosomal DNA under elevated temperatures. Further, the ONSEN promoter is free of CG and CHG sites, and the reduction of DNA methylation at the CHH sites is not sufficient to activate the element. Since dividing cells have a more pronounced heat response, the extrachromosomal ONSEN DNA, capable of reintegrating into the genome, accumulates preferentially in the meristematic tissue of the shoot. The recruitment of a major plant heat shock transcription factor in periods of heat stress exploits the plant's heat stress response to achieve the transposon's activation, making it impossible for the host to respond appropriately to stress without losing control over the invader.

  8. Hygiene problems in practice. Pt. 2. Central freshwater heating systems; Hygieneprobleme in der Praxis. T. 2. Zentrale Trinkwassererwaermungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Kremer, Robert [DVGW-Fachausschuss Trinkwasserhygiene in Gebaeuden, Leverkusen (Germany)

    2009-02-15

    Hygienically safe freshwater heating is the subject of this two-installment article series. Relevant standards and regulations are discussed, and the legionella problem in central freshwater heating systems is gone into. The second part of the series describes dimensioning errors which result in overdimensioning, which in turn may quickly cause hygiene problems. (orig.)

  9. Plant hydraulics as a central hub integrating plant and ecosystem function: meeting report for 'Emerging Frontiers in Plant Hydraulics' (Washington, DC, May 2015).

    Science.gov (United States)

    Sack, Lawren; Ball, Marilyn C; Brodersen, Craig; Davis, Stephen D; Des Marais, David L; Donovan, Lisa A; Givnish, Thomas J; Hacke, Uwe G; Huxman, Travis; Jansen, Steven; Jacobsen, Anna L; Johnson, Daniel M; Koch, George W; Maurel, Christophe; McCulloh, Katherine A; McDowell, Nate G; McElrone, Andrew; Meinzer, Frederick C; Melcher, Peter J; North, Gretchen; Pellegrini, Matteo; Pockman, William T; Pratt, R Brandon; Sala, Anna; Santiago, Louis S; Savage, Jessica A; Scoffoni, Christine; Sevanto, Sanna; Sperry, John; Tyerman, Stephen D; Way, Danielle; Holbrook, N Michele

    2016-09-01

    Water plays a central role in plant biology and the efficiency of water transport throughout the plant affects both photosynthetic rate and growth, an influence that scales up deterministically to the productivity of terrestrial ecosystems. Moreover, hydraulic traits mediate the ways in which plants interact with their abiotic and biotic environment. At landscape to global scale, plant hydraulic traits are important in describing the function of ecological communities and ecosystems. Plant hydraulics is increasingly recognized as a central hub within a network by which plant biology is connected to palaeobiology, agronomy, climatology, forestry, community and ecosystem ecology and earth-system science. Such grand challenges as anticipating and mitigating the impacts of climate change, and improving the security and sustainability of our food supply rely on our fundamental knowledge of how water behaves in the cells, tissues, organs, bodies and diverse communities of plants. A workshop, 'Emerging Frontiers in Plant Hydraulics' supported by the National Science Foundation, was held in Washington DC, 2015 to promote open discussion of new ideas, controversies regarding measurements and analyses, and especially, the potential for expansion of up-scaled and down-scaled inter-disciplinary research, and the strengthening of connections between plant hydraulic research, allied fields and global modelling efforts.

  10. Reducing And Analysizing of Flow Accelerated Corrosion at Thermal Power Plant, Heat Recovery Steam Generators

    OpenAIRE

    Akın Avşaroğlu; Suphi URAL

    2017-01-01

    The purpose of this study is to Reducing and Analysing of Flow Accelerated Corrosion in Thermal Plant Heat Recovery Steam Generators. All these studies have been performed in a new and 16 year-old established Combined Cycle Power Plants in Turkey. Corrosion cases have been investigated due to Mechanical Outage Reports at Power Plant in 2011-2015. Flow Accelerated Corrosion study has been based on specific zone related with Economizer Low Pressure connection pipings. It was issued a performanc...

  11. Heat-Rate Improvement Obtained by Retubing Power-Plant Condenser Enhanced Tubes

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-21

    A utility will only retube a condenser with enhanced tubes if the incremental cost of the enhanced tubes can be offset with reduced fuel costs. The reduced fuel cost is obtained for some units because of the higher heat-transfer coefficient of enhanced tubes. They lead to improved condenser performance measured by a lower condenser pressure and therefore a more efficient power plant. However, the higher haet-transfer coefficients do not always guarantee that enhanced tubes will be more cost effective. Other issues must be considered such as the cooling-water flow reduction due to the increased pressure drop, the low-pressure turbine heat-rate variation with backpressure, and the cooling-water pump and system characteristics. These and other parameters must be considered to calculate the efficiency improvement of the power plant as commonly measured by the quantity known as the heat rate. Knowing the heat-rate improvement, the fuel cost, and the incremental increase of the enhanced tubes from the supplier, the payback time can be determined. This program calculates the heat-rate improvement that can be obtained by retubing a power plant condenser with enhanced tubes of a particular type called Korodense LPD made by Wolverine Tube, Inc. The fuel savings are easily established knowing the heat-rate improvement. All electrical utilities are potential users because a condenser is used as the heat sink for every power plant.

  12. HTRATE; Heat-Rate Improvement Obtained by Retubing Power-Plant Condenser Enhanced Tubes

    Energy Technology Data Exchange (ETDEWEB)

    Rabas, T.J. [Argonne National Lab., IL (United States)

    1990-06-01

    A utility will only retube a condenser with enhanced tubes if the incremental cost of the enhanced tubes can be offset with reduced fuel costs. The reduced fuel cost is obtained for some units because of the higher heat-transfer coefficient of enhanced tubes. They lead to improved condenser performance measured by a lower condenser pressure and therefore a more efficient power plant. However, the higher haet-transfer coefficients do not always guarantee that enhanced tubes will be more cost effective. Other issues must be considered such as the cooling-water flow reduction due to the increased pressure drop, the low-pressure turbine heat-rate variation with backpressure, and the cooling-water pump and system characteristics. These and other parameters must be considered to calculate the efficiency improvement of the power plant as commonly measured by the quantity known as the heat rate. Knowing the heat-rate improvement, the fuel cost, and the incremental increase of the enhanced tubes from the supplier, the payback time can be determined. This program calculates the heat-rate improvement that can be obtained by retubing a power plant condenser with enhanced tubes of a particular type called Korodense LPD made by Wolverine Tube, Inc. The fuel savings are easily established knowing the heat-rate improvement. All electrical utilities are potential users because a condenser is used as the heat sink for every power plant.

  13. Central station applications planning activities and supporting studies. [application of photovoltaic technology to power generation plants

    Science.gov (United States)

    Leonard, S. L.; Siegel, B.

    1980-01-01

    The application of photovoltaic technology in central station (utility) power generation plants is considered. A program of data collection and analysis designed to provide additional information about the subset of the utility market that was identified as the initial target for photovoltaic penetration, the oil-dependent utilities (especially muncipals) of the U.S. Sunbelt, is described along with a series of interviews designed to ascertain utility industry opinions about the National Photovoltaic Program as it relates to central station applications.

  14. Uranium accumulation by aquatic plants from uranium-contaminated water in Central Portugal.

    Science.gov (United States)

    Pratas, João; Favas, Paulo J C; Paulo, Carlos; Rodrigues, Nelson; Prasad, M N V

    2012-03-01

    Several species of plants have developed a tolerance to metal that enables them to survive in metal contaminated and polluted sites. Some of these aquatic plants have been reported to accumulate significant amounts of specific trace elements and are, therefore, useful for phytofiltration. This work focuses the potential of aquatic plants for the phytofiltration of uranium (U) from contaminated water. We observed that Callitriche stagnalis, Lemna minor, and Fontinalis antipyretica, which grow in the uraniferous geochemical province of Central Portugal, have been able to accumulate significant amounts of U. The highest concentration of U was found in Callitriche stagnalis (1948.41 mg/kg DW), Fontinalis antipyretica (234.79 mg/kg DW), and Lemna minor (52.98 mg/kg DW). These results indicate their potential for the phytofiltration of U through constructed treatment wetlands or by introducing these plants into natural water bodies in the uraniferous province of Central Portugal.

  15. Codigestion of manure and organic wastes in centralized biogas plants: status and future trends.

    Science.gov (United States)

    Angelidaki, I; Ellegaard, L

    2003-01-01

    Centralized biogas plants in Denmark codigest mainly manure, together with other organic waste such as industrial organic waste, source sorted household waste, and sewage sludge. Today 22 large-scale centralized biogas plants are in operation in Denmark, and in 2001 they treated approx 1.2 million tons of manure as well as approx 300,000 of organic industrial waste. Besides the centralized biogas plants there are a large number of smaller farm-scale plants. The long-term energy plan objective is a 10-fold increase of the 1998 level of biogas production by the year 2020. This will help to achieve a target of 12-14% of the national energy consumption being provided by renewable energy by the year 2005 and 33% by the year 2030. A major part of this increase is expected to come from new centralized biogas plants. The annual potential for biogas production from biomass resources available in Denmark is estimated to be approx 30 Peta Joule (PJ). Manure comprises about 80% of this potential. Special emphasis has been paid to establishing good sanitation and pathogen reduction of the digested material, to avoid risk of spreading pathogens when applying the digested manure as fertilizer to agricultural soils.

  16. Central Nervous System Effects of Ginkgo Biloba, a Plant Extract.

    Science.gov (United States)

    Itil, Turan M.; Eralp, Emin; Tsambis, Elias; Itil, Kurt Z.; Stein, Ulrich

    1996-01-01

    Extracts of Ginkgo biloba (EGb) are among the most prescribed drugs in France and Germany. EGb is claimed to be effective in peripheral arterial disorders and in "cerebral insufficiency." The mechanism of action is not yet well understood. Three of the ingredients of the extract have been isolated and found to be pharmacologically active, but which one alone or in combination is responsible for clinical effects is unknown. The recommended daily dose (3 x 40 mg extract) is based more on empirical data than on clinical dose-findings studies. However, despite these, according to double-blind, placebo-controlled clinical trials, EGb has therapeutic effects, at least, on the diagnostic entity of "cerebral insufficiency," which is used in Europe as synonymous with early dementia. To determine whether EGb has significant pharmacological effects on the human brain, a pharmacodynamic study was conducted using the Quantitative Pharmacoelectroencephalogram (QPEEG(R)) method. It was established that the pharmacological effects (based on a predetermined 7.5--13.0-Hz alpha frequency band in a computer-analyzed electroencephalogram = CEEG(R)) of EGb on the central nervous system (CNS) are significantly different than placebo, and the high and low doses could be discriminated from each other. The 120-mg, but particularly the 240-mg, single doses showed the most consistent CNS effects with an earlier onset (1 h) and longer duration (7 h). Furthermore, it was established that the electrophysiological effects of EGb in CNS are similar to those of well-known cognitive activators such as "nootropics" as well as tacrine, the only marketed "antidementia" drug currently available in the United States.

  17. Waste heat recovery options in a large gas-turbine combined power plant

    Science.gov (United States)

    Upathumchard, Ularee

    This study focuses on power plant heat loss and how to utilize the waste heat in energy recovery systems in order to increase the overall power plant efficiency. The case study of this research is a 700-MW natural gas combined cycle power plant, located in a suburban area of Thailand. An analysis of the heat loss of the combustion process, power generation process, lubrication system, and cooling system has been conducted to evaluate waste heat recovery options. The design of the waste heat recovery options depends to the amount of heat loss from each system and its temperature. Feasible waste heat sources are combustion turbine (CT) room ventilation air and lubrication oil return from the power plant. The following options are being considered in this research: absorption chillers for cooling with working fluids Ammonia-Water and Water-Lithium Bromide (in comparison) and Organic Rankine Cycle (ORC) with working fluids R134a and R245fa. The absorption cycles are modeled in three different stages; single-effect, double-effect and half-effect. ORC models used are simple ORC as a baseline, ORC with internal regenerator, ORC two-phase flash expansion ORC and ORC with multiple heat sources. Thermodynamic models are generated and each system is simulated using Engineering Equation Solver (EES) to define the most suitable waste heat recovery options for the power plant. The result will be synthesized and evaluated with respect to exergy utilization efficiency referred as the Second Law effectiveness and net output capacity. Results of the models give recommendation to install a baseline ORC of R134a and a double-effect water-lithium bromide absorption chiller, driven by ventilation air from combustion turbine compartment. The two technologies yield reasonable economic payback periods of 4.6 years and 0.7 years, respectively. The fact that this selected power plant is in its early stage of operation allows both models to economically and effectively perform waste heat

  18. The Impact of Implementation of Total quality Management on Plants' Productivity: Evidence from Poultry Processing Plants- Saudi Arabia- Central Region

    Directory of Open Access Journals (Sweden)

    ELHAJ ABDELMOULA.ELSIDDIG MUSA,

    2011-05-01

    Full Text Available Productivity index as an important business determinant factor for profitability and business performance has been studied in this research versus TQM varibles. The study highlighted out the impacts ofimplementation of TQM on productivity in poultry processing plants in Saudi Arabia – Central Region. The significance of this research represented in exploring the impact of TQM practices on Poultry Processing Plants' productivity. Seven determinants of TQM practices and their impacts were measured against productivity. The determinants included top management commitment, customer focus, rewards & training, continual improvement, cooperation & teamwork, prevention focus and measurement system. Data was collected by using Questionnaire tool. The Questionnaire is of closed ended questions. It consists of three parts, the first part is demographic information about the study sample, the second part about implementation of the total quality management and the third part is to measure productivity. A sample of three poultry processing plants that effectively implemented total quality management were purposively chosen out of eight plants in Saudi Arabia Central Region. The study respondents are purposively chosen which consists quality team, production supervisors, Total quality management and production managers. 73 respondents out 75 participated in the survey. The finding indicated that the TQM practices have positive impact on poultry processing plants' productivity.

  19. Application of microwave heating to a polyesterification plant

    NARCIS (Netherlands)

    Komorowska-Durka, M.

    2015-01-01

    Utilizing microwave irradiation, a fundamentally different method of the energy transfer, to the chemical process units can potentially be advantageous compared to the conventional heating, inter alia due to the selective nature of interaction of the microwaves with the matter. This doctoral dissert

  20. Shock Structure and Shock Heating in the Galactic Central Molecular Zone

    CERN Document Server

    Ott, Juergen; Jones, Paul; Meier, David S

    2014-01-01

    We present maps of a large number of dense molecular gas tracers across the Central Molecular Zone of our Galaxy. The data were taken with the CSIRO/CASS Mopra telescope in Large Projects in the 1.3cm, 7mm, and 3mm wavelength regimes. Here, we focus on the brightness of the shock tracers SiO and HNCO, molecules that are liberated from dust grains under strong (SiO) and weak (HNCO) shocks. The shocks may have occurred when the gas enters the bar regions and the shock differences could be due to differences in the moving cloud mass. Based on tracers of ionizing photons, it is unlikely that the morphological differences are due to selective photo-dissociation of the molecules. We also observe direct heating of molecular gas in strongly shocked zones, with a high SiO/HNCO ratios, where temperatures are determined from the transitions of ammonia. Strong shocks appear to be the most efficient heating source of molecular gas, apart from high energy emission emitted by the central supermassive black hole Sgr A* and t...

  1. Feedback quality and environmentally friendly use of domestic central heating systems.

    Science.gov (United States)

    Sauer, J; Schmeink, C; Wastell, D G

    2007-06-01

    The study examined the influence of system-embedded feedback on user behaviour during the environmentally friendly operation of a central heating system. A PC-based simulation, called CHESS, was developed to model the critical features of a central heating system. After having received 30 min of training on the simulation task, 60 participants worked on a series of operational scenarios under different levels of system feedback. In addition to the collection of various performance measures (e.g. energy consumption, energy wastage), a range of user variables was collected (e.g. environmental concern). As hypothesized, the results showed that increased feedback resulted in improved environmentally friendly performance and, more importantly, the specific feedback indicator influenced the type of strategy used to improve human - machine system performance. A major implication is that system designers need to develop feedback indicators that are chiefly influenced by user behaviour and are largely immune to factors that are beyond the user's control (e.g. weather conditions).

  2. Heat integration of an Olefins Plant: Pinch Analysis and mathematical optimization working together

    Directory of Open Access Journals (Sweden)

    M. Beninca

    2011-03-01

    Full Text Available This work explores a two-step, complexity reducing methodology, to analyze heat integration opportunities of an existing Olefins Plant, identify and quantify reduction of energy consumption, and propose changes of the existing heat exchanger network to achieve these goals. Besides the analysis of plant design conditions, multiple operational scenarios were considered to propose modifications for handling real plant operation (flexibility. On the strength of plant complexity and large dimension, work methodology was split into two parts: initially, the whole plant was evaluated with traditional Pinch Analysis tools. Several opportunities were identified and modifications proposed. Modifications were segregated to represent small and independent portions of the original process. One of them was selected to be re-analyzed, considering two scenarios. Reduction of problem dimension allowed mathematical methodologies (formulation with decomposition, applying LP, MILP and NLP optimization methods to synthesize flexible networks to be applied, generating a feasible modification capable of fulfilling the proposed operational scenarios.

  3. A preliminary classification of wetland plant communities in north-central Minnesota

    Science.gov (United States)

    Cowardin, L.M.; Johnson, D.H.

    1973-01-01

    A classification of wetland plant communities was developed for a study area in north-central Minnesota in order to analyze data on waterfowl use of habitat that were gathered by radio telemetry. The classification employs features of several earlier classifications in addition to new classes for bogs and lakeshore communities. Brief descriptions are given for each community, and the important plant species are listed. Discriminant function analysis was used for 40 plant species. Seventy-five percent of the stands studied were classified correctly by this technique. Average probabilities of assignment to communities were calculated and helped to identify distinct and poorly defined communities as well as the relationship among communities.

  4. Two-phase distribution in the vertical flow line of a domestic wet central heating system

    Directory of Open Access Journals (Sweden)

    Ge Y.T.

    2013-04-01

    Full Text Available The theoretical and experimental aspects of bubble distribution in bubbly two-phase flow are reviewed in the context of the micro bubbles present in a domestic gas fired wet central heating system. The latter systems are mostly operated through the circulation of heated standard tap water through a closed loop circuit which often results in water supersaturated with dissolved air. This leads to micro bubble nucleation at the primary heat exchanger wall, followed by detachment along the flow. Consequently, a bubbly two-phase flow characterises the flow line of such systems. The two-phase distribution across the vertical and horizontal pipes was measured through a consideration of the volumetric void fraction, quantified through photographic techniques. The bubble distribution in the vertical pipe in down flow conditions was measured to be quasi homogenous across the pipe section with a negligible reduction in the void fraction at close proximity to the pipe wall. Such a reduction was more evident at lower bulk fluid velocities.

  5. Two-phase distribution in the vertical flow line of a domestic wet central heating system

    Science.gov (United States)

    Fsadni, A.-M.; Ge, Y. T.

    2013-04-01

    The theoretical and experimental aspects of bubble distribution in bubbly two-phase flow are reviewed in the context of the micro bubbles present in a domestic gas fired wet central heating system. The latter systems are mostly operated through the circulation of heated standard tap water through a closed loop circuit which often results in water supersaturated with dissolved air. This leads to micro bubble nucleation at the primary heat exchanger wall, followed by detachment along the flow. Consequently, a bubbly two-phase flow characterises the flow line of such systems. The two-phase distribution across the vertical and horizontal pipes was measured through a consideration of the volumetric void fraction, quantified through photographic techniques. The bubble distribution in the vertical pipe in down flow conditions was measured to be quasi homogenous across the pipe section with a negligible reduction in the void fraction at close proximity to the pipe wall. Such a reduction was more evident at lower bulk fluid velocities.

  6. Controversy over Biomass Plant at Florida State Heats up

    Science.gov (United States)

    Mangan, Katherine

    2009-01-01

    This article reports that Florida State University officials are gearing up for what could be another bruising battle this month over a proposed biomass plant that could bring the campus cleaner, cheaper energy and monetary support for alternative-energy research. Or, it could bring noise and pollution to a nearby neighborhood, according to…

  7. A centralized hazardous waste treatment plant: the facilities of the ZVSMM at Schwabach as an example

    Energy Technology Data Exchange (ETDEWEB)

    Amsoneit, Norbert [Zweckverband Sondermuell-Entsorgung Mittelfranken, Rednitzhembach (Germany)

    1993-12-31

    In this work a centralized hazardous waste treatment plant is described and its infra-structure is presented. Special emphasis is given to the handling of the residues produced and the different treatment processes at the final disposal. 2 refs., 4 figs.

  8. Potential use of power plant reject heat in commercial aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    Olszewski, M.

    1977-01-01

    Current research and commercial activities in aquaculture operations have been reviewed. An aquaculture system using mostly herbivorous species in pond culture is proposed as a means of using waste heat to produce reasonably priced protein. The system uses waste water streams, such as secondary sewage effluent, animal wastes, or some industrial waste streams as a primary nutrient source to grow algae, which is fed to fish and clams. Crayfish feed on the clam wastes thereby providing a clean effluent from the aquaculture system. Alternate fish associations are presented and it appears that a carp or tilapia association is desirable. An aquaculture system capable of rejecting all the waste heat from a 1000-MW(e) power station in winter can accommodate about half the summer heat rejection load. The aquaculture facility would require approximately 133 ha and would produce 4.1 x 10/sup 5/ kg/year of fish, 1.5 x 10/sup 6/ kg/year of clam meat, and 1.5 x 10/sup 4/ kg/year of live crayfish. The estimated annual pretax profit from this operation is one million dollars. Several possible problem areas have been identified. However, technical solutions appear to be readily available to solve these problems. The proposed system shows considerable economic promise. Small scale experiments have demonstrated the technical feasibility of various components of the system. It therefore appears that a pilot scale experimental facility should be operated.

  9. Reducing And Analysizing of Flow Accelerated Corrosion at Thermal Power Plant, Heat Recovery Steam Generators

    Directory of Open Access Journals (Sweden)

    Akın Avşaroğlu

    2017-01-01

    Full Text Available The purpose of this study is to Reducing and Analysing of Flow Accelerated Corrosion in Thermal Plant Heat Recovery Steam Generators. All these studies have been performed in a new and 16 year-old established Combined Cycle Power Plants in Turkey. Corrosion cases have been investigated due to Mechanical Outage Reports at Power Plant in 2011-2015. Flow Accelerated Corrosion study has been based on specific zone related with Economizer Low Pressure connection pipings. It was issued a performance report. Results and lessons learnt from these studies will be used as a preventive action manner in all similar Plants.

  10. Fungal root endophyte associations of plants endemic to the Pamir Alay Mountains of Central Asia.

    Science.gov (United States)

    Zubek, Szymon; Nobis, Marcin; Błaszkowski, Janusz; Mleczko, Piotr; Nowak, Arkadiusz

    2011-06-01

    The fungal root endophyte associations of 16 species from 12 families of plants endemic to the Pamir Alay Mountains of Central Asia are presented. The plants and soil samples were collected in Zeravshan and Hissar ranges within the central Pamir Alay mountain system. Colonization by arbuscular mycorrhizal fungi (AMF) was found in 15 plant species; in 8 species it was of the Arum type and in 4 of the Paris type, while 3 taxa revealed intermediate arbuscular mycorrhiza (AM) morphology. AMF colonization was found to be absent only in Matthiola integrifolia, the representative of the Brassicaceae family. The AM status and morphology are reported for the first time for all the species analyzed and for the genera Asyneuma, Clementsia, and Eremostachys. Mycelia of dark septate endophytes (DSE) accompanied the AMF colonization in ten plant species. The frequency of DSE occurrence in the roots was low in all the plants, with the exception of Spiraea baldschuanica. However, in the case of both low and higher occurrence, the percentage of DSE root colonization was low. Moreover, the sporangia of Olpidium spp. were sporadically found inside the root epidermal cells of three plant species. Seven AMF species (Glomeromycota) found in the trap cultures established with soils surrounding roots of the plants being studied were reported for the first time from this region of Asia. Our results provide information that might well be of use to the conservation and restoration programmes of these valuable plant species. The potential application of beneficial root-inhabiting fungi in active plant protection projects of rare, endemic and endangered plants is discussed.

  11. High Flux Central Receivers of Molten Salts for the New Generation of Commercial Stand-Alone Solar Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Lata, J. M.; Rodriguez, M.; Alvarez de Lara, M.

    2006-07-01

    Molten salt technology represents nowadays the most cost-effective technology for electricity generation for stand-alone Solar Power Plants. Although this technology can be applied to both concentrating technologies, Parabolic TROUGH and Central Receiver Systems (CRS), CRS technology can take advantages from its high concentration, allowing to work at high temperatures and therefore with a reduction in the size and cost of the storage system. The Receiver System is the door for which the energy passes from the field collector to the thermal-electric cycle; it represents, therefore, the core of the CRS System. SENER and CIEMAT are joining forces to face up the challenge of sizing and designing a molten salt Receiver of high thermal efficiency, able to operate at high fluxes without compromising its durability (at least 25 years). The advances in design and studies of different materials, to operate at high fluxes using molten salts as heat transfer fluid, will be presented hereafter. (Author)

  12. Application of solar energy in heating and cooling of residential buildings under Central Asian conditions

    Directory of Open Access Journals (Sweden)

    Usmonov Shukhrat Zaurovich

    2014-04-01

    Full Text Available Solar radiation is the main source of thermal energy for almost all the processes developing in the atmosphere, hydrosphere, and biosphere. The total duration of sunshine in Tajikistan ranges from 2100 to 3170 hours per year. Solar collectors can be mounted on the roof of a house after its renovation and modernization. One square meter of surface area in Central Asia accounts for up to 1600 kW/h of solar energy gain, whilst the average gain is 1200 kW/h. Active solar thermal systems are able to collect both low- and high-temperature heat. Active systems require the use of special engineering equipment for the collection, storage, conversion and distribution of heat, while a low-grade system is based on the principle of using a flat solar collector. The collector is connected to the storage tank for storing the heated water, gas, etc. The water temperature is in the range 50-60 °C. For summer air conditioning in hot climates, absorption-based solar installations with open evaporating solution are recommended. The UltraSolar PRO system offers an opportunity to make a home independent of traditional electricity. Combining Schneider Electric power generation and innovative energy storage technology results in an independent power supply. Traditional power supply systems can be short-lived since they store energy in lead-acid batteries which have a negligible lifetime. Lead-acid batteries operate in a constant charge-discharge mode, require specific conditions for best performance and can fail suddenly. Sudden failure of lead acid batteries, especially in winter in the northern part of Tajikistan, completely disables the heating system of a building. Instead, it is recommended to use industrial lithium-ion batteries, which have a significantly longer life and reliability compared to lead-acid type. UltraSolar PRO are ideal and provide a complete package, low noise and compact lithium-ion power supply.

  13. [Root architecture of two desert plants in central Hexi Corridor of Northwest China].

    Science.gov (United States)

    Shan, Li-Shan; Li, Yi; Ren, Wei; Su, Shi-Ping; Dong, Qiu-Lian; Geng, Dong-Mei

    2013-01-01

    In this study, the root systems of desert plant species Reaumuria soongorica and Nitraria tangutorum in the central Hexi Corridor of Northwest China were excavated by shovel, and the characteristics of the plant root architecture were analyzed by using topology and fractal theory. The root topological indices of the two desert plants were small, and the root branching patterns were herringbone-like. The roots of the two desert plants had obvious fractal characteristics, with the fractal dimension of R. soongorica and N. tangutorum being (1.18 +/- 0.04) and (1.36 +/- 0.06), respectively. The root fractal dimension and fractal abundance were significantly positively correlated with the root average link length. The root average link lengths of the two plants were long, which enlarged the plants' effective nutrition space, and thus, made the plants adapt to the dry and infertile soil environment. The sums of the root cross-sectional areas before and after the root bifurcation of the two desert plants were equal, which verified the principle of Leonardo da Vinci. A total of 17 parameters of root architecture were analyzed by the principal component analysis. The parameters of root topological structure, numbers of root links, stepwise branching ratio, and root diameter could well present the root architecture characteristics of the two desert plants.

  14. Thermoeconomic Analysis of Hybrid Power Plant Concepts for Geothermal Combined Heat and Power Generation

    OpenAIRE

    Florian Heberle; Dieter Brüggemann

    2014-01-01

    We present a thermo-economic analysis for a low-temperature Organic Rankine Cycle (ORC) in a combined heat and power generation (CHP) case. For the hybrid power plant, thermal energy input is provided by a geothermal resource coupled with the exhaust gases of a biogas engine. A comparison to alternative geothermal CHP concepts is performed by considering variable parameters like ORC working fluid, supply temperature of the heating network or geothermal water temperature. Second law efficiency...

  15. 吸收式热泵用于热电联产改造新技术%The Co-production of New Technology Transformation of Usage of Absorption Hot-pump to Recycle Waste Heat in Heat Power Plant

    Institute of Scientific and Technical Information of China (English)

    茹毅; 王飞

    2012-01-01

    热电厂的循环冷却水系统存在大量的低位热能。热泵系统具有将低位热能提升为高位热能的能力。本文即是根据山西某热电厂的节能改造方案介绍了利用吸收式热泵系统回收电厂冷凝余热用于集中供热的新技术;并对新型供热系统做出能效和经济性评价,认为新技术应用具有经济和环境的双重效益,有广阔发展前景。%There is a large number of low level heat energy in the circulating cooling water system of thermal power plant.Heat pump system has the ability to improve the heat energy level from low order into high order.This article introduced the new technology,application to central heating,of usage of absorption high temperature heat pump system for recycling waste heat of condensation which based on the energy-saving reform plan of one heat-power plant in Shanxi province.Based on the new central heating systems the energy efficiency and economic evaluation be giving in this paper.Through the analysis shows that the application of new technology has the double effect in economic efficiency and environmental protection that has broad prospects for development.

  16. 10 CFR Appendix M to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Central Air Conditioners and Heat Pumps

    Science.gov (United States)

    2010-01-01

    ... of Central Air Conditioners and Heat Pumps M Appendix M to Subpart B of Part 430 Energy DEPARTMENT OF... Consumption of Central Air Conditioners and Heat Pumps 1. DEFINITIONS 2. TESTING CONDITIONS 2.1Test room... conditioners and heat pumps, and systems composed of multiple mini-split units (outdoor units located...

  17. Design and analysis of a cogeneration plant using heat recovery of a cement factory

    OpenAIRE

    2015-01-01

    There is a more potential in a cement factory for electric power generation using waste heat recovery compared to the other industries. A case study has been done at a cement factory having two units, 1600 TPD and 5500 TPD, identified three waste heat rejections at 176 °C, 330 °C and 420 °C and designed a suitable power plant configuration. In this work, an attempt has been made to quantify the power generation capacity with plant analysis. It has been resulted that 12.5 MW of power can be pr...

  18. Thermoeconomic Analysis of Hybrid Power Plant Concepts for Geothermal Combined Heat and Power Generation

    Directory of Open Access Journals (Sweden)

    Florian Heberle

    2014-07-01

    Full Text Available We present a thermo-economic analysis for a low-temperature Organic Rankine Cycle (ORC in a combined heat and power generation (CHP case. For the hybrid power plant, thermal energy input is provided by a geothermal resource coupled with the exhaust gases of a biogas engine. A comparison to alternative geothermal CHP concepts is performed by considering variable parameters like ORC working fluid, supply temperature of the heating network or geothermal water temperature. Second law efficiency as well as economic parameters show that hybrid power plants are more efficient compared to conventional CHP concepts or separate use of the energy sources.

  19. Steam generators and waste heat boilers for process and plant engineers

    CERN Document Server

    Ganapathy, V

    2014-01-01

    Incorporates Worked-Out Real-World ProblemsSteam Generators and Waste Heat Boilers: For Process and Plant Engineers focuses on the thermal design and performance aspects of steam generators, HRSGs and fire tube, water tube waste heat boilers including air heaters, and condensing economizers. Over 120 real-life problems are fully worked out which will help plant engineers in evaluating new boilers or making modifications to existing boiler components without assistance from boiler suppliers. The book examines recent trends and developments in boiler design and technology and presents novel idea

  20. Solar tower power plant using a particle-heated steam generator: Modeling and parametric study

    Science.gov (United States)

    Krüger, Michael; Bartsch, Philipp; Pointner, Harald; Zunft, Stefan

    2016-05-01

    Within the framework of the project HiTExStor II, a system model for the entire power plant consisting of volumetric air receiver, air-sand heat exchanger, sand storage system, steam generator and water-steam cycle was implemented in software "Ebsilon Professional". As a steam generator, the two technologies fluidized bed cooler and moving bed heat exchangers were considered. Physical models for the non-conventional power plant components as air- sand heat exchanger, fluidized bed coolers and moving bed heat exchanger had to be created and implemented in the simulation environment. Using the simulation model for the power plant, the individual components and subassemblies have been designed and the operating parameters were optimized in extensive parametric studies in terms of the essential degrees of freedom. The annual net electricity output for different systems was determined in annual performance calculations at a selected location (Huelva, Spain) using the optimized values for the studied parameters. The solution with moderate regenerative feed water heating has been found the most advantageous. Furthermore, the system with moving bed heat exchanger prevails over the system with fluidized bed cooler due to a 6 % higher net electricity yield.

  1. A Novel Modeling of Molten-Salt Heat Storage Systems in Thermal Solar Power Plants

    Directory of Open Access Journals (Sweden)

    Rogelio Peón Menéndez

    2014-10-01

    Full Text Available Many thermal solar power plants use thermal oil as heat transfer fluid, and molten salts as thermal energy storage. Oil absorbs energy from sun light, and transfers it to a water-steam cycle across heat exchangers, to be converted into electric energy by means of a turbogenerator, or to be stored in a thermal energy storage system so that it can be later transferred to the water-steam cycle. The complexity of these thermal solar plants is rather high, as they combine traditional engineering used in power stations (water-steam cycle or petrochemical (oil piping, with the new solar (parabolic trough collector and heat storage (molten salts technologies. With the engineering of these plants being relatively new, regulation of the thermal energy storage system is currently achieved in manual or semiautomatic ways, controlling its variables with proportional-integral-derivative (PID regulators. This makes the overall performance of these plants non optimal. This work focuses on energy storage systems based on molten salt, and defines a complete model of the process. By defining such a model, the ground for future research into optimal control methods will be established. The accuracy of the model will be determined by comparing the results it provides and those measured in the molten-salt heat storage system of an actual power plant.

  2. Solar heat storages in district heating networks

    Energy Technology Data Exchange (ETDEWEB)

    Ellehauge, K. (Ellehauge og Kildemoes, AArhus (DK)); Engberg Pedersen, T. (COWI A/S, Kgs. Lyngby (DK))

    2007-07-15

    This report gives information on the work carried out and the results obtained in Denmark on storages for large solar heating plants in district heating networks. Especially in Denmark the share of district heating has increased to a large percentage. In 1981 around 33% of all dwellings in DK were connected to a district heating network, while the percentage in 2006 was about 60% (in total 1.5 mio. dwellings). In the report storage types for short term storage and long term storages are described. Short term storages are done as steel tanks and is well established technology widely used in district heating networks. Long term storages are experimental and used in connection with solar heating. A number of solar heating plants have been established with either short term or long term storages showing economy competitive with normal energy sources. Since, in the majority of the Danish district heating networks the heat is produced in co-generation plants, i.e. plants producing both electricity and heat for the network, special attention has been put on the use of solar energy in combination with co-generation. Part of this report describes that in the liberalized electricity market central solar heating plants can also be advantageous in combination with co-generation plants. (au)

  3. 集中供热系统的自控%Automatic Control of Central Heating System

    Institute of Scientific and Technical Information of China (English)

    石宏伟

    2001-01-01

    介绍了在集中供热系统中,采用二次水供水温度自控、二次水循环泵变频调速、二次水循环量自控、二次网水力平衡控制、部分建筑供水温度分时自控等措施,进行节能技术改造的方法和节能效果。%This paper describes the measures of controlling temperature ofsecondary water, frequency converting of secondary circulation pumps, controlling flow of secondary water, controlling hydraulic balance of secondary network and controlling temperature of supply water of buildings according to time in central heating system. This paper also introduces the methods and effects of saving energy by technical reconstruction.

  4. Using flowering and heat-loss models for improving greenhouse energy-use efficiency in annual bedding plant production

    Science.gov (United States)

    In temperate climates, annual bedding plants are typically produced in heated greenhouses from late winter through early summer. Temperature, photoperiod, light intensity, and transplant date are commonly manipulated during commercial production so that plants are in flower for predetermined market ...

  5. Control of distributed heat transfer mechanisms in membrane distillation plants

    KAUST Repository

    Laleg-Kirati, Taous-Meriem

    2017-01-05

    Various examples are provided that are related to boundary control in membrane distillation (MD) processes. In one example, a system includes a membrane distillation (MD) process comprising a feed side and a permeate side separated by a membrane boundary layer; and processing circuitry configured to control a water production rate of the MD process based at least in part upon a distributed heat transfer across the membrane boundary layer. In another example, a method includes determining a plurality of estimated temperature states of a membrane boundary layer separating a feed side and a permeate side of a membrane distillation (MD) process; and adjusting inlet flow rate or inlet temperature of at least one of the feed side or the permeate side to maintain a difference temperature along the membrane boundary layer about a defined reference temperature based at least in part upon the plurality of estimated temperature states.

  6. Determining Reliability Parameters for a Closed-Cycle Small Combined Heat and Power Plant

    Directory of Open Access Journals (Sweden)

    Vysokomorny Vladimir S.

    2016-01-01

    Full Text Available The paper provides numerical values of the reliability parameters for independent power sources within the ambient temperature and output power range corresponding to the operation under the climatic conditions of Eastern Siberia and the Far East of the Russian Federation. We have determined the optimal values of the parameters necessary for the reliable operation of small CHP plants (combined heat and power plants providing electricity for isolated facilities.

  7. Optimization of a local district heating plant under fuel flexibility and performance

    DEFF Research Database (Denmark)

    Rudra, Souman; Rosendahl, Lasse; From, Niels

    2011-01-01

    Brovst is a small district in Denmark. Based on the case of Brovst, this paper analyses the role of district heating in future Renewable Energy Systems. The present use of fossil fuels in the Brovst DHP (district heating plant) represents an increasing environmental and climate-related load. So......, an investigation has been made to reduce the use of fossil fuels for district heating system and make use of the local renewable resources (Biogas, Solar and Geothermal) for district heating purpose. In this article, the techno-economic assessment is achieved through the development of a suite of models...... that are combined to give cost and performance data for this district heating system. Different local fuels have been analyzed for different perspectives to find the way to optimize the whole integrated system in accordance with fuel availability and cost. This paper represents the energy system analysis mode...

  8. Finned tubes in purified gas heat exchangers of flue gas desulfurization plant

    Energy Technology Data Exchange (ETDEWEB)

    O' Donnell, J. Jr.; Meyer, T.H.

    1985-01-01

    The use of helical rolled, corrosion resistant finned tubes in the purified gas heat exchangers of flue gas desulfurization plant has considerable economic advantages over conventional heat exchangers with smooth tubes. As a result of a threefold larger external surface and hence improved heat transfer properties, heat exchangers with finned tubes can be made considerably smaller. The weight and space requirements are reduced and the pressure drop also falls owing to the smaller diameter. Thus piping, pumps, and fittings can all be made smaller. Moreover, deposition on the finned tubes is considerably lower. It is found that finned tubes can be recommended in all cases where the difference in heat transfer coefficients between the inside and the outside of the tube is considerable. (orig.).

  9. A critical evaluation of semianalytic methods in the study of centrally heated, unresolved, infrared sources

    Science.gov (United States)

    Doty, Steven D.; Leung, Chun Ming

    1994-01-01

    We critically evaluate current methods of analysis in infrared (IR) astronomy and investigate the conditions under which these semianalytic methods are reliable. Specifically we examine the usual assumptions of homogeneities in dust density and temperature, and neglect of opacity effects when applied to internally heated, unresolved IR sources. To accomplish this, a series of radiation transport models for these sources have been constructed. The model results are treated as observed quantities and analyzed to derive the source parameters, using simple semianalytic methods. The discrepancies between the derived and actual model parameters can then be attributed to the limitations of the analysis methods and provide a measure of their reliability. Applying this approach to centrally heated, unresolved IR sources, we have studied in detail the following diagnostic problems: (1) determination of dust mass from monochromatic and integrated luminosities; (2) estimation of dust temperature distribution from color temperatures derived from the flux spectrum; and (3) determination of the empirical grain emissivity law (opacity function) for both continuum and spectral features.

  10. Effect of drought and heat stresses on plant growth and yield: a review

    Science.gov (United States)

    Lipiec, J.; Doussan, C.; Nosalewicz, A.; Kondracka, K.

    2013-12-01

    Drought and heat stresses are important threat limitations to plant growth and sustainable agriculture worldwide. Our objective is to provide a review of plant responses and adaptations to drought and elevated temperature including roots, shoots, and final yield and management approaches for alleviating adverse effects of the stresses based mostly on recent literature. The sections of the paper deal with plant responses including root growth, transpiration, photosynthesis, water use efficiency, phenotypic flexibility, accumulation of compounds of low molecular mass (eg proline and gibberellins), and expression of some genes and proteins for increasing the tolerance to the abiotic stresses. Soil and crop management practices to alleviate negative effects of drought and heat stresses are also discussed. Investigations involving determination of plant assimilate partitioning, phenotypic plasticity, and identification of most stress-tolerant plant genotypes are essential for understanding the complexity of the responses and for future plant breeding. The adverse effects of drought and heat stress can be mitigated by soil management practices, crop establishment, and foliar application of growth regulators by maintaining an appropriate level of water in the leaves due to osmotic adjustment and stomatal performance.

  11. Roles of Protein Synthesis Elongation Factor EF-Tu in Heat Tolerance in Plants

    Directory of Open Access Journals (Sweden)

    Jianming Fu

    2012-01-01

    Full Text Available EF-Tu proteins of plastids, mitochondria, and the cytosolic counterpart EF-1α in plants, as well as EF-Tu proteins of bacteria, are highly conserved and multifunctional. The functions of EF-Tu include transporting the aminoacyl-tRNA complex to the A site of the ribosome during protein biosynthesis; chaperone activity in protecting other proteins from aggregation caused by environmental stresses, facilitating renaturation of proteins when conditions return to normal; displaying a protein disulfide isomerase activity; participating in the degradation of N-terminally blocked proteins by the proteasome; eliciting innate immunity and triggering resistance to pathogenic bacteria in plants; participating in transcription when an E. coli host is infected with phages. EF-Tu genes are upregulated by abiotic stresses in plants, and EF-Tu plays important role in stress responses. Expression of a plant EF-Tu gene confers heat tolerance in E. coli, maize knock-out EF-Tu null mutants are heat susceptible, and over-expression of an EF-Tu gene improves heat tolerance in crop plants. This review paper summarizes the current knowledge of EF-Tu proteins in stress responses in plants and progress on application of EF-Tu for developing crop varieties tolerant to abiotic stresses, such as high temperatures.

  12. 15 Years of R&D in Central Solar Heating in Denmark

    DEFF Research Database (Denmark)

    Heller, Alfred

    2000-01-01

    and acceptance of higher energy price are necessary. Further technical development and push towards a market is required. Especially the development of economical storage technologies is decisive. Work with steel tanks, concrete tanks, aquifer storage, bore hole storage and most importantly, from a Danish view...... and the application of variable flow that lead to novelties in the control strategy. The plant is described and experiences are analysed. The presented cases show that the technology, under special conditions, can be economically competitive with other heating technologies. Under normal conditions, public funding......, pit water storage is presented and conclusions are drawn. R&D in the field of CSHPs call for international co-operation, knowledge transfer and not least financing. The structural and political climate that shapes the boundaries of the R&D activities and also makes up the dominant barrier...

  13. Perapion connexum (Schilsky, 1902 (Coleoptera, Apionidae in Central Europe, a case of plant expansion chase

    Directory of Open Access Journals (Sweden)

    Marek Wanat

    2012-03-01

    Full Text Available Perapion connexum (Schilsky is recorded for the first time from Hungary and Kyrgyzstan, and new distribution data from Ukraine and Russia are provided. Preliminary placements of this weevil in faunal checklists for Poland and Slovakia are here documented with detailed data. Its occurrence in Austria based on older evidence, is discussed. The neophytic and invasive in Central Europe sorrel Rumex confertus Willd. is confirmed to be its unique host plant in Poland. Morphology of the newcoming weevil is described and illustrated, and the key to all Central European species of Perapion is presented.

  14. Perapion connexum (Schilsky, 1902) (Coleoptera, Apionidae) in Central Europe, a case of plant expansion chase

    Science.gov (United States)

    Wanat, Marek; Podlussány, Attila; Schön, Karel

    2012-01-01

    Abstract Perapion connexum (Schilsky) is recorded for the first time from Hungary and Kyrgyzstan, and new distribution data from Ukraine and Russia are provided. Preliminary placements of this weevil in faunal checklists for Poland and Slovakia are here documented with detailed data. Its occurrence in Austria based on older evidence, is discussed. The neophytic and invasive in Central Europe sorrel Rumex confertus Willd. is confirmed to be its unique host plant in Poland. Morphology of the newcoming weevil is described and illustrated, and the key to all Central European species of Perapion is presented. PMID:22451784

  15. Aerial thermography studies of power plant heated lakes

    Energy Technology Data Exchange (ETDEWEB)

    Villa-Aleman, E.

    2000-01-26

    Remote sensing temperature measurements of water bodies is complicated by the temperature differences between the true surface or skin water and the bulk water below. Weather conditions control the reduction of the skin temperature relative to the bulk water temperature. Typical skin temperature depressions range from a few tenths of a degree Celsius to more than one degree. In this research project, the Savannah River Technology Center (SRTC) used aerial thermography and surface-based meteorological and water temperature measurements to study a power plant cooling lake in South Carolina. Skin and bulk water temperatures were measured simultaneously for imagery calibration and to produce a database for modeling of skin temperature depressions as a function of weather and bulk water temperatures. This paper will present imagery that illustrates how the skin temperature depression was affected by different conditions in several locations on the lake and will present skin temperature modeling results.

  16. Thermal analysis of heat and power plant with high temperature reactor and intermediate steam cycle

    Directory of Open Access Journals (Sweden)

    Fic Adam

    2015-03-01

    Full Text Available Thermal analysis of a heat and power plant with a high temperature gas cooled nuclear reactor is presented. The main aim of the considered system is to supply a technological process with the heat at suitably high temperature level. The considered unit is also used to produce electricity. The high temperature helium cooled nuclear reactor is the primary heat source in the system, which consists of: the reactor cooling cycle, the steam cycle and the gas heat pump cycle. Helium used as a carrier in the first cycle (classic Brayton cycle, which includes the reactor, delivers heat in a steam generator to produce superheated steam with required parameters of the intermediate cycle. The intermediate cycle is provided to transport energy from the reactor installation to the process installation requiring a high temperature heat. The distance between reactor and the process installation is assumed short and negligable, or alternatively equal to 1 km in the analysis. The system is also equipped with a high temperature argon heat pump to obtain the temperature level of a heat carrier required by a high temperature process. Thus, the steam of the intermediate cycle supplies a lower heat exchanger of the heat pump, a process heat exchanger at the medium temperature level and a classical steam turbine system (Rankine cycle. The main purpose of the research was to evaluate the effectiveness of the system considered and to assess whether such a three cycle cogeneration system is reasonable. Multivariant calculations have been carried out employing the developed mathematical model. The results have been presented in a form of the energy efficiency and exergy efficiency of the system as a function of the temperature drop in the high temperature process heat exchanger and the reactor pressure.

  17. Physiological, biochemical, and molecular mechanisms of heat stress tolerance in plants.

    Science.gov (United States)

    Hasanuzzaman, Mirza; Nahar, Kamrun; Alam, Md Mahabub; Roychowdhury, Rajib; Fujita, Masayuki

    2013-05-03

    High temperature (HT) stress is a major environmental stress that limits plant growth, metabolism, and productivity worldwide. Plant growth and development involve numerous biochemical reactions that are sensitive to temperature. Plant responses to HT vary with the degree and duration of HT and the plant type. HT is now a major concern for crop production and approaches for sustaining high yields of crop plants under HT stress are important agricultural goals. Plants possess a number of adaptive, avoidance, or acclimation mechanisms to cope with HT situations. In addition, major tolerance mechanisms that employ ion transporters, proteins, osmoprotectants, antioxidants, and other factors involved in signaling cascades and transcriptional control are activated to offset stress-induced biochemical and physiological alterations. Plant survival under HT stress depends on the ability to perceive the HT stimulus, generate and transmit the signal, and initiate appropriate physiological and biochemical changes. HT-induced gene expression and metabolite synthesis also substantially improve tolerance. The physiological and biochemical responses to heat stress are active research areas, and the molecular approaches are being adopted for developing HT tolerance in plants. This article reviews the recent findings on responses, adaptation, and tolerance to HT at the cellular, organellar, and whole plant levels and describes various approaches being taken to enhance thermotolerance in plants.

  18. Expression of E. coli heat-labile enterotoxin B subunit in transgenic tobacco plants

    Institute of Scientific and Technical Information of China (English)

    LIU Hong-li; ZHANG Zheng; LI Wen-sheng; ZHENG Jing; KONG Ling-hong; WANG Yi-li; SI Lü-sheng

    2005-01-01

    Objective: To construct plant transformation vector containing Escherichia coli heat-labile enterotoxin B subunit (LT-B) gene and generate LT-B transgenic tobacco plants. Methods: The LT-B coding sequence was amplified from pMMB68 by PCR, subcloned into middle vector pUCmT and binary vector pBI121 to obtain plant expression vector pBI-LTB, in which LT-B expression was controlled under the Cauliflower mosaic virus (CaMV) 35S promoter. The tobacco plants (Nicotiana tobacum L. Cuttivar Xanthi) were transformed by co-cultivating leaf discs method via Agrobacterium tumefaciens LBA4404 harboring the plant expression vector. The regenerated transgenic tobacco plants were selected by kanamycin and confirmed by PCR, Southern blot, Western blot and ELISA. Results: LT-B gene integrated in the tobacco genomic DNA and were expressed in 9 strains of transgenic tobacco plants. The yield was varied from 3.36-10.56 ng/mg total soluble tobacco leaf protein. Conclusion: The plant binary expression vector pBILTB was constructed successfully, and transgenic LT-B tobacco plants was generated, and confirmed by Southern blot. The protein LT-B expressed by engineered plants was identified by Western blot analysis and had the expected molecular weight of LT-B pentamer protein. This result is an important step close to developing an edible vaccine and supplying a mucasal immunoajuvant, which will contribute to the prevention of mucosa-route evading pathogen.

  19. Study of flue gas condensing for biofuel fired heat and power plants; Studie av roekgaskondensering foer biobraensleeldade kraftvaermeanlaeggningar

    Energy Technology Data Exchange (ETDEWEB)

    Axby, Fredrik; Gustafsson, J.O.; Nystroem, Johan; Johansson, Kent

    2000-11-01

    This report considers questions regarding flue gas condensing plants connected to bio-fuelled heat and power plants. The report consists of two parts, one where nine existing plants are described regarding technical issues and regarding the experience from the different plants. Part two is a theoretical study where heat balance calculations are made to show the technical and economical performance in different plant configurations and operating conditions. Initially the different parts in the flue gas condensing plant are described. Tube, plate and scrubber condensers are described briefly. The different types of humidifiers are also described, rotor, cross-stream plate heat exchanger and scrubber. Nine flue gas-condensing plants have been visited. The plants where chosen considering it should be bio-fuel fired plant primarily heat and power plants. Furthermore we tried to get a good dissemination considering plant configuration, supplier, geographical position, operating situation and plant size. The description of the different plants focuses on the flue gas condenser and the belonging components. The fuel, flue gas and condensate composition is described as well as which materials are used in the different parts of the plant. The experience from operating the plants and the reasons of why they decided to chose the actual condenser supplier are reported.

  20. Recycled Water Reuse Permit Renewal Application for the Central Facilities Area Sewage Treatment Plant

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Mike [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    This renewal application for a Recycled Water Reuse Permit is being submitted in accordance with the Idaho Administrative Procedures Act 58.01.17 “Recycled Water Rules” and the Municipal Wastewater Reuse Permit LA-000141-03 for continuing the operation of the Central Facilities Area Sewage Treatment Plant located at the Idaho National Laboratory. The permit expires March 16, 2015. The permit requires a renewal application to be submitted six months prior to the expiration date of the existing permit. For the Central Facilities Area Sewage Treatment Plant, the renewal application must be submitted by September 16, 2014. The information in this application is consistent with the Idaho Department of Environmental Quality’s Guidance for Reclamation and Reuse of Municipal and Industrial Wastewater and discussions with Idaho Department of Environmental Quality personnel.

  1. Portable pilot plant for evaluating marine biofouling growth and control in heat exchangers-condensers.

    Science.gov (United States)

    Casanueva, J F; Sánchez, J; García-Morales, J L; Casanueva-Robles, T; López, J A; Portela, J R; Nebot, E; Sales, D

    2003-01-01

    Biofouling frequently involves a serious impediment to achieving optimum operating conditions in heat exchangers-condensers. The economic coat and energy losses associated with this phenomenon are significant and the environmental impact of biocides must satisfy stringent regulations. A portable pilot plant has been designed in order to carry out in-situ experimental study as biofilm is formed under thermal and hydrodynamically controlled conditions. The pilot plant has an automatic monitoring, control and data acquisition system, which automatically processes data from indirect measure of fouling in terms of increased fluid frictional and heat transfer resistances. A particular method is used and proposed for direct measuring and biofilm characterization. Once we know the actual film thickness, we can calculate the effective thermal conductivity of the layer by using the appropriate heat transfer equations.

  2. Importance of heat transfer in an anaerobic digestion plant in a continental climate context.

    Science.gov (United States)

    Merlin, Gérard; Kohler, François; Bouvier, Maele; Lissolo, Thierry; Boileau, Hervé

    2012-11-01

    Investigation on the sensivity to temperature variations has been achieved on a full-scale experimental dairy wastewater treatment plant including an unheated but insulated upflow anaerobic sludge blanket. A simple steady-state heat transfer model based on energy balance has been designed to forecast the biogas production depending on ambient air and dairy wastewater temperatures variations. Energy balance has been described for any part of the digestion plant. Calculated heat losses were in the same range than observed losses with an uncertainty of about 10%. From the equalization tank to the digester the average heat loss under cold period was close to 10°C due to convection and conduction. Mesophilic conditions are not respected for couples of ambient air and wastewater temperatures ranging respectively from 8-35 to 35-29°C. Technical solutions are suggested to increase the biogas production.

  3. Rehabilitation of heat exchange equipment a key to power plant life extension and performance improvement

    Energy Technology Data Exchange (ETDEWEB)

    Taveau, F.; Huiban, A.M. [Alstom Power Heat Exchange, 78 - Velizy Villacoublay (France)

    2001-07-01

    With the current evolutions of the energy market and the life extension of the power plants, all the equipment initially supplied need one day or another partial or total rehabilitation. For heat exchange equipment, this includes the condensers, feed water heaters and various heat exchangers. Modernization is in particular necessary when in-service monitoring and periodic inspections show significant deteriorations of the tubes and cooling water leakages leading to forced outages or when tube and tube plate materials are no longer suited to cooling water characteristics or to updated specifications of the secondary system. Feedwater heaters and heat exchangers damaged by erosion/corrosion, vibrations, etc. can be re-designed, manufactured and replaced easily. The operation is more complex on condensers and requires technical surveys, study of alternative solutions and has a more direct impact on the global output of the power plant. That is why our conference will focus on the condenser refurbishment. (author)

  4. Heat rate curve approximation for power plants without data measuring devices

    Energy Technology Data Exchange (ETDEWEB)

    Poullikkas, Andreas [Electricity Authority of Cyprus, P.O. Box 24506, 1399 Nicosia (CY

    2012-07-01

    In this work, a numerical method, based on the one-dimensional finite difference technique, is proposed for the approximation of the heat rate curve, which can be applied for power plants in which no data acquisition is available. Unlike other methods in which three or more data points are required for the approximation of the heat rate curve, the proposed method can be applied when the heat rate curve data is available only at the maximum and minimum operating capacities of the power plant. The method is applied on a given power system, in which we calculate the electricity cost using the CAPSE (computer aided power economics) algorithm. Comparisons are made when the least squares method is used. The results indicate that the proposed method give accurate results.

  5. Heat rate curve approximation for power plants without data measuring devices

    Directory of Open Access Journals (Sweden)

    Andreas Poullikkas

    2012-01-01

    Full Text Available In this work, a numerical method, based on the one-dimensional finite difference technique, is proposed for the approximation of the heat rate curve, which can be applied for power plants in which no data acquisition is available. Unlike other methods in which three or more data points are required for the approximation of the heat rate curve, the proposed method can be applied when the heat rate curve data is available only at the maximum and minimum operating capacities of the power plant. The method is applied on a given power system, in which we calculate the electricity cost using the CAPSE (computer aided power economics algorithm. Comparisons are made when the least squares method is used. The results indicate that the proposed method give accurate results.

  6. Utilization of waste heat from rotary kiln for burning clinker in the cement plant

    Directory of Open Access Journals (Sweden)

    Sztekler Karol

    2016-01-01

    Full Text Available Cement subsector next to the glass industry is counted among one of the most energy-intensive industries, which absorbs approx. 12-15% of the total energy consumed by the industry. In the paper various methods of energy consumption reduction of in the cement industry are discussed. Cement production carries a very large emissions of greenhouse gases, where CO2 emissions on a global scale with the industry than approx. 5%. Great opportunity in CO2 emissions reduction in addition to the recovery of waste heat is also alternative fuels co-firing in cement kilns [1], [2]. In the cement sector interest in fitting-usable waste energy is growing in order to achieve high rates of savings and hence the financial benefits, as well as the environment ones [3]. In the process of cement production is lost irretrievably lot of energy and reduction of these losses on a global scale gives a visible saving of consumed fuel. The aim of this study is to investigate the possibility of waste heat use in Rudniki Cement Plant near to Czestochowa. After analyzing of all waste heat sources will be analyzed the heat emitted by radiation from the surface of the rotary kiln at the relevant facility. On the basis of thermal-flow calculations the most favorable radiative heat exchanger will be designed. The calculations based on available measurements provided by the cement plant, a thermal power of the heat exchanger, the heat exchange surface, the geometry of the heat exchanger, and other important parameters will be established. In addition the preliminary calculations of hydraulic losses and set directions for further work will be carried out. Direct benefits observed with the introduction of the broader heat recovery technology, is a significant increase in energy efficiency of the industrial process, which is reflected in the reduction of energy consumption and costs. Indirectly it leads to a reduction of pollution and energy consumption.

  7. Master Control and Data Acquisition System for a Solar Central Receiver Electric Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Soderstrand, M.A. (Sandia Labs., Albuquerque, NM); Darsey, D.M. (Aerospace Corp., El Segundo, CA); Rountree, R.C. (California Univ., Livermore); Sheahan, R.R. (Southern California Edison Co., Los Angeles)

    1979-09-01

    A design of the 10-megawatt electric Solar Central Receiver Power Plant currently under construction in Barstow, California is described. Consideration is given to the collector, receiver, and thermal storage subsystems. The circuits and systems concepts related to the Master Control and Data Acquisition Systems are emphasized. Implementation of the Master Control Subsystem, operational requirements, and software are discussed along with its status and expectations.

  8. Heat-induced release of epigenetic silencing reveals the concealed role of an imprinted plant gene.

    Directory of Open Access Journals (Sweden)

    Diego H Sanchez

    2014-11-01

    Full Text Available Epigenetic mechanisms suppress the transcription of transposons and DNA repeats; however, this suppression can be transiently released under prolonged heat stress. Here we show that the Arabidopsis thaliana imprinted gene SDC, which is silent during vegetative growth due to DNA methylation, is activated by heat and contributes to recovery from stress. SDC activation seems to involve epigenetic mechanisms but not canonical heat-shock perception and signaling. The heat-mediated transcriptional induction of SDC occurs particularly in young developing leaves and is proportional to the level of stress. However, this occurs only above a certain window of absolute temperatures and, thus, resembles a thermal-sensing mechanism. In addition, the re-silencing kinetics during recovery can be entrained by repeated heat stress cycles, suggesting that epigenetic regulation in plants may conserve memory of stress experience. We further demonstrate that SDC contributes to the recovery of plant biomass after stress. We propose that transcriptional gene silencing, known to be involved in gene imprinting, is also co-opted in the specific tuning of SDC expression upon heat stress and subsequent recovery. It is therefore possible that dynamic properties of the epigenetic landscape associated with silenced or imprinted genes may contribute to regulation of their expression in response to environmental challenges.

  9. Electric protections based in microprocessors in power plants; Protecciones electricas basadas en microprocesadores en centrales generadoras

    Energy Technology Data Exchange (ETDEWEB)

    Libreros, Domitilo; Castanon Jimenez, Jose Ismael [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1987-12-31

    This article is centered around the substitution of the conventional electric protections of a power plant in connection type unit for protections based in microprocessors. A general model of conventional protection of a power plant is described and the number of analogic and digital signals that intervene in that model are quantified. A model is setup for power plant protection with microprocessors, analyzing each one of the modules that would form it. Finally, the algorithms to carry on such protection are presented. [Espanol] Este articulo se centra en torno a la sustitucion de las protecciones electricas convencionales de una central generadora en conexion tipo unidad por protecciones basadas en microprocesadores. Se describe el modelo general de proteccion convencional de una central generadora y se cuantifica el numero de senales analogicas y digitales que interviene en dicho modelo. Se propone un modelo para proteccion de centrales generadoras mediante microprocesadores, analizandose cada uno de los modulos que lo conformarian. Finalmente, se presentan los algoritmos para realizar dicha proteccion.

  10. Drought versus heat: What's the major constraint on Mediterranean green roof plants?

    Energy Technology Data Exchange (ETDEWEB)

    Savi, Tadeja, E-mail: tsavi@units.it [Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, 34127 Trieste (Italy); Dal Borgo, Anna, E-mail: dalborgo.anna@gmail.com [Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, 34127 Trieste (Italy); Love, Veronica L., E-mail: vllove1@sheffield.ac.uk [Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, 34127 Trieste (Italy); Department of Landscape, University of Sheffield, Western Bank, Sheffield, South Yorkshire S10 2TN (United Kingdom); Andri, Sergio, E-mail: s.andri@seic.it [Harpo seic verdepensile, Via Torino 34, 34123 Trieste (Italy); Tretiach, Mauro, E-mail: tretiach@units.it [Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, 34127 Trieste (Italy); Nardini, Andrea, E-mail: nardini@units.it [Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, 34127 Trieste (Italy)

    2016-10-01

    Green roofs are gaining momentum in the arid and semi-arid regions due to their multiple benefits as compared with conventional roofs. One of the most critical steps in green roof installation is the selection of drought and heat tolerant species that can thrive under extreme microclimate conditions. We monitored the water status, growth and survival of 11 drought-adapted shrub species grown on shallow green roof modules (10 and 13 cm deep substrate) and analyzed traits enabling plants to cope with drought (symplastic and apoplastic resistance) and heat stress (root membrane stability). The physiological traits conferring efficiency/safety to the water transport system under severe drought influenced plant water status and represent good predictors of both plant water use and growth rates over green roofs. Moreover, our data suggest that high substrate temperature represents a stress factor affecting plant survival to a larger extent than drought per se. In fact, the major cause influencing seedling survival on shallow substrates was the species-specific root resistance to heat, a single and easy measurable trait that should be integrated into the methodological framework for screening and selection of suitable shrub species for roof greening in the Mediterranean. - Highlights: • The use of hardy shrub species for roof greening should be increased. • We monitored water status of 11 shrub species growing on shallow green roofs. • Species heat and drought tolerance, growth, and survival were studied. • High substrate temperature significantly affected plant survival. • Root resistance to heat could be used as trait for species selection for green roofs.

  11. Plants contain a novel multi-member class of heat shock factors without transcriptional activator potential.

    Science.gov (United States)

    Czarnecka-Verner, E; Yuan, C X; Scharf, K D; Englich, G; Gurley, W B

    2000-07-01

    Based on phylogeny of DNA-binding domains and the organization of hydrophobic repeats, two families of heat shock transcription factors (HSFs) exist in plants. Class A HSFs are involved in the activation of the heat shock response, but the role of class B HSFs is not clear. When transcriptional activities of full-length HSFs were monitored in tobacco protoplasts, no class B HSFs from soybean or Arabidopsis showed activity under control or heat stress conditions. Additional assays confirmed the finding that the class B HSFs lacked the capacity to activate transcription. Fusion of a heterologous activation domain from human HSF1 (AD2) to the C-terminus of GmHSFB1-34 gave no evidence of synergistic enhancement of AD2 activity, which would be expected if weak activation domains were present. Furthermore, activity of AtHSFB1-4 (class B) was not rescued by coexpression with AtHSFA4-21 (class A) indicating that the class A HSF was not able to provide a missing function required for class B activity. The transcriptional activation potential of Arabidopsis AtHSFA4-21 was mapped primarily to a 39 amino acid fragment in the C-terminus enriched in bulky hydrophobic and acidic residues. Deletion mutagenesis of the C-terminal activator regions of tomato and Arabidopsis HSFs indicated that these plant HSFs lack heat-inducible regulatory regions analogous to those of mammalian HSF1. These findings suggest that heat shock regulation in plants may differ from metazoans by partitioning negative and positive functional domains onto separate HSF proteins. Class A HSFs are primarily responsible for stress-inducible activation of heat shock genes whereas some of the inert class B HSFs may be specialized for repression, or down-regulation, of the heat shock response.

  12. Perspectives on deciphering mechanisms underlying plant heat stress response and thermotolerance

    Directory of Open Access Journals (Sweden)

    Kamila Lucia Bokszczanin

    2013-08-01

    Full Text Available Global warming is a major threat for agriculture and food safety and in many cases the negative effects are already apparent. The current challenge of basic and applied plant science is to decipher the molecular mechanisms of heat stress response and thermotolerance in detail and use this information to identify genotypes that will withstand unfavorable environmental conditions. Nowadays X-omics approaches complement the findings of previous targeted studies and highlight the complexity of heat stress response mechanisms giving information for so far unrecognized genes, proteins and metabolites as potential key players of thermotolerance. Even more, roles of epigenetic mechanisms and the involvement of small RNAs in thermotolerance are currently emerging and thus open new directions of yet unexplored areas of plant heat stress response. In parallel it is emerging that although the whole plant is vulnerable to heat, specific organs are particularly sensitive to elevated temperatures. This has redirected research from the vegetative to generative tissues. The sexual reproduction phase is considered as the most sensitive to heat and specifically pollen exhibits the highest sensitivity and frequently an elevation of the temperature just a few degrees above the optimum during pollen development can have detrimental effects for crop production. Compared to our knowledge on heat stress response of vegetative tissues, the information on pollen is still scarce. Nowadays, several techniques for high-throughput X-omics approaches provide major tools to explore the principles of pollen heat stress response and thermotolerance mechanisms in specific genotypes. The collection of such information will provide an excellent support for improvement of breeding programs to facilitate the development of tolerant cultivars. The review aims at describing the current knowledge of thermotolerance mechanisms and the technical advances which will foster new insights into

  13. A Model for Optimization and Analysis of Energy Flexible Boiler Plants for Building Heating Purposes

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, J.R.

    1996-05-01

    This doctoral thesis presents a model for optimization and analysis of boiler plants. The model optimizes a boiler plant with respect to the annual total costs or with respect to energy consumption. The optimum solution is identified for a given number of energy carriers and defined characteristics of the heat production units. The number of heat production units and the capacity of units related to each energy carrier or the capacity of units related to the same energy carrier can be found. For a problem comprising large variation during a defined analysis period the model gives the operating costs and energy consumption to be used in an extended optimization. The model can be used to analyse the consequences with respect to costs and energy consumption due to capacity margins and shifts in the boundary conditions. The model is based on a search approach comprising an operational simulator. The simulator is based on a marginal cost method and dynamic programming. The simulation is performed on an hourly basis. A general boiler characteristic representation is maintained by linear energy or cost functions. The heat pump characteristics are represented by tabulated performance and efficiency as function of state and nominal aggregate capacities. The simulation procedure requires a heat load profile on an hourly basis. The problem of the presence of capacity margins in boiler plants is studied for selected cases. The single-boiler, oil-fired plant is very sensitive to the magnitude of the losses present during burner off-time. For a plant comprising two oil-fired burners, the impact of a capacity margin can be dampened by the selected capacity configuration. The present incentive, in Norway, to install an electric element boiler in an oil-fired boiler plant is analysed. 77 refs., 74 figs., 12 tabs.

  14. Land surface and atmospheric conditions associated with heat waves over the Chickasaw Nation in the South Central United States

    Science.gov (United States)

    Lee, Eungul; Bieda, Rahama; Shanmugasundaram, Jothiganesh; Basara Richter, Heather

    2016-06-01

    Exposure to extreme heat was reconstructed based on regional land-atmosphere processes from 1979 to 2010 in the South Central U.S. The study region surrounds the Chickasaw Nation (CN), a predominantly Native American population with a highly prevalent burden of climate-sensitive chronic diseases. Land surface and atmospheric conditions for summer heat waves were analyzed during spring (March-April-May, MAM) and summer (June-July-August, JJA) based on the Climate and Ocean: Variability, Predictability, and Change maximum temperature definition for heat wave frequency (HWF). The spatial-temporal pattern of HWF was determined using empirical orthogonal function (EOF) analysis and the corresponding principle component time series of the first EOF of HWF. Statistically significant analyses of observed conditions indicated that sensible heat increased and latent heat fluxes decreased with high HWF in the South Central U.S. The largest positive correlations of sensible heat flux to HWF and the largest negative correlations of latent heat flux to HWF were specifically observed over the CN. This is a significantly different energy transfer regime due to less available soil moisture during the antecedent MAM and JJA. The higher sensible heat from dry soil could cause significant warming from the near surface (>2.0°C) to the lower troposphere (>1.5°C), and accumulated boundary layer heat could induce the significant patterns of higher geopotential height and enhance anticyclonic circulations (negative vorticity anomaly) at the midtroposphere. Results suggested a positive land-atmosphere feedback associated with heat waves and called attention to the need for region-specific climate adaptation planning.

  15. Ethnobotanical and ethnomedicinal uses of plants in the district of Acquapendente (Latium, Central Italy).

    Science.gov (United States)

    Guarrera, Paolo Maria; Forti, Gianluca; Marignoli, Silvia

    2005-01-15

    In the years 2002-2003 research was carried out concerning ethnomedicine in the Acquapendente district (Viterbo, Latium, central Italy), an area so far less frequently studied from the perspective of plant folk traditions. The district, from the ethnobotanical point of view, shows traces of the influences of the neighbouring regions. In this study 96 plant entities are described, belonging to 45 families, of which 64 are employed in human medicine, 15 in veterinary medicine, 22 in the feeding of domestic animals, 5 as antiparasitics and 5 for other uses. Some medicinal uses are linked to beliefs or residual forms of magic prescriptions (11 plants). Amongst the more notable uses the most interesting are those of: Verbena officinalis (rheumatic pains, wounds), Juglans regia (antiparasitic use for cheeses), Santolina etrusca (antimoth use), Stellaria media and Lupinus albus (birdseed for poultry and fodder for lambs), and Thymus longicaulis subsp. longicaulis (used to curdle milk).

  16. Ozone risk assessment for plants: Central role of metabolism-dependent changes in reducing power

    Energy Technology Data Exchange (ETDEWEB)

    Dizengremel, Pierre [Faculte des Sciences et Techniques, UMR1137 Ecologie et Ecophysiologie Forestieres, Nancy-Universite, BP239, F-54506 Vandoeuvre-les-Nancy Cedex (France)], E-mail: pierre.dizengremel@scbiol.uhp-nancy.fr; Le Thiec, Didier [INRA, UMR1137 Ecologie et Ecophysiologie Forestieres, Centre INRA de Nancy, F-54280 Champenoux (France)], E-mail: le_thiec@nancy.inra.fr; Bagard, Matthieu [Faculte des Sciences et Techniques, UMR1137 Ecologie et Ecophysiologie Forestieres, Nancy-Universite, BP239, F-54506 Vandoeuvre-les-Nancy Cedex (France)], E-mail: matthieu.bagard@scbiol.uhp-nancy.fr; Jolivet, Yves [Faculte des Sciences et Techniques, UMR1137 Ecologie et Ecophysiologie Forestieres, Nancy-Universite, BP239, F-54506 Vandoeuvre-les-Nancy Cedex (France)], E-mail: yves.jolivet@scbiol.uhp-nancy.fr

    2008-11-15

    The combination of stomatal-dependent ozone flux and total ascorbate level is currently presented as a correct indicator for determining the degree of sensitivity of plants to ozone. However, the large changes in carbon metabolism could play a central role in the strategy of the foliar cells in response to chronic ozone exposure, participating in the supply of reducing power and carbon skeletons for repair and detoxification, and modifying the stomatal mode of functioning. To reinforce the accuracy of the definition of the threshold for ozone risk assessment, it is proposed to also consider the redox pool (NAD(P)H), the ratio between carboxylases and the water use efficiency as indicators of the differential ozone tolerance of plants. - We propose reducing power, Rubisco/PEPc ratio and water use efficiency as additional indicators in ozone risk assessment for plants.

  17. Ethnomedicinal plants used by the people of Manang district, central Nepal

    Directory of Open Access Journals (Sweden)

    Chaudhary Ram P

    2006-10-01

    Full Text Available Abstract Background The district of Manang (2000 – 6000 m is located in the Central Himalayas, Nepal. The majority of local inhabitants of the area are Gurungs, of Tibetan origin. The remoteness of the region has resulted in continued use of plants as medicine in an area where the ethnobotany has sparsely been documented. Methods Interviews were conducted with amchi (Tibetan medicinal practitioners, local healers (including priests locally known as 'lamas', plant traders, and knowledgeable villagers (including herders regarding local plant names and their medicinal uses during several field visits (2002–2005. When convenient to the locals, a jungle or forest walk was done with the healers, allowing for both plant collection and detailed information gathering. Results This present research documented 91 ethnomedicinal plant species, belonging to 40 families under 73 genera, and 45 new ethnomedicinal plant species are added. These 91 locally used medicinal plants are found to treat 93 ailments. This study provides information on 45 plant species previously unknown for their medicinal uses in Manang. The indication for use, mode of preparation, dose and administration of medicine are described in detail for each species. Conclusion This wealth of ethnobotanical knowledge persists, and is being transferred to the next generation in some areas in upper Manang, in a country where this is often not the case. The senior amchi of the area (Karma Sonam Lama, who has been practicing Tibetan medicine for three generations, feels that it is of utmost importance to conserve the traditional healing system and to pass his knowledge on to the local community about the importance of medicinal plants. He hopes that this will lead to the conservation and sustainable management of medicinal plants in the villages. Over the duration of this research, the prices of several rare medicinal plants of Manang increased dramatically, highlighting both the scarcity and

  18. Heat flow and subsurface temperature distributions in central and western New York. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hodge, D.S.; Fromm, K.

    1984-01-01

    Initiation of a geothermal energy program in western and central New York requires knowledge of subsurface temperatures for targeting areas of potential resources. The temperature distribution in possible geothermal reservoirs, calculated from heat flow measurements and modeling techniques, shows that a large area of New York can be considered for exploitation of geothermal resources. Though the temperatures at currently accessible depths show the availability of only a low-temperature (less than 100/sup 0/C), direct-use resource, this can be considered as an alternative for the future energy needs of New York State. From analysis of bottom-hole-temperature data and direct heat flow measurements, estimates of temperatures in the Cambrian Sandstones provide the basis of the economic evaluation of the reservoir. This reservoir contains the extractable fluids needed for targeting a potential geothermal well site in the low-temperature geothermal target zone. In the northern section of the Appalachian basin, reservoir temperatures in the Cambrian are below 50/sup 0/C but may be over 80/sup 0/C in the deeper parts of the basin in southern New York State. Using a minimum of 50/sup 0/C as a useful reservoir temperature, temperatures in excess of this value are encountered in the Theresa Formation at depths in excess of 1300 meters. Considering a maximum depth for economical drilling to be 2500 meters with present technology, the 2500 meters to the Theresa (sea level datum) forms the lower limit of the geothermal resource. Temperatures in the range of 70/sup 0/C to 80/sup 0/C are predicted for the southern portion of New York State.

  19. District heating and cooling system for communities through power plant retrofit and distribution network. Final report, Phase I

    Energy Technology Data Exchange (ETDEWEB)

    1979-06-01

    The technical and economic feasibility of retrofitting thermal power plants in Minnesota to accommodate both heat and power generation for district heating was examined and is discussed. Three communities were identified as viable sites for co-generation district heating. (LCL)

  20. Preliminary issues associated with the next generation nuclear plant intermediate heat exchanger design

    Science.gov (United States)

    Natesan, K.; Moisseytsev, A.; Majumdar, S.

    2009-07-01

    The Next Generation Nuclear Plant, with emphasis on production of both electricity and hydrogen, involves helium as the coolant and a closed-cycle gas turbine for power generation with a core outlet/gas turbine inlet temperature of 850-950 °C. In this concept, an intermediate heat exchanger is used to transfer the heat from primary helium from the core to the secondary fluid, which can be helium, a nitrogen/helium mixture, or a molten salt. This paper assesses the issues pertaining to shell-and-tube and compact heat exchangers. A detailed thermal-hydraulic analysis was performed to calculate heat transfer, temperature distribution, and pressure drop inside both printed circuit and shell-and-tube heat exchangers. The analysis included evaluation of the role of key process parameters, geometrical factors in heat exchanger designs, and material properties of structural alloys. Calculations were performed for helium-to-helium, helium-to-helium/nitrogen, and helium-to-salt heat exchangers.

  1. Seawater desalination plant using nuclear heating reactor coupled with MED process

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A small size plant for seawater desalination using nuclear heating reactor coupled with MED process was developed by the Institute of Nuclear Energy Technology, Tsinghua University, China. This seawater desalination plant was designed to supply potable water demand to some coastal location or island where both fresh water and energy source are severely lacking. It is also recommended as a demonstration and training facility for seawater desalination using nuclear energy. The design of small size of seawater desalination plant couples two proven technologies: Nuclear Heating Reactor (NHR) and Multi-Effect Destination (MED) process. The NHR design possesses intrinsic and passive safety features, which was demonstrated by the experiences of the project NHR-5. The intermediate circuit and steam circuit were designed as the safety barriers between the NHR reactor and MED desalination system. Within 10~200 MWt of the power range of the heating reactor, the desalination plant could provide 8000 to 150,000 m3/d of high quality potable water. The design concept and parameters, safety features and coupling scheme are presented.

  2. Drought versus heat: What's the major constraint on Mediterranean green roof plants?

    Science.gov (United States)

    Savi, Tadeja; Dal Borgo, Anna; Love, Veronica L; Andri, Sergio; Tretiach, Mauro; Nardini, Andrea

    2016-10-01

    Green roofs are gaining momentum in the arid and semi-arid regions due to their multiple benefits as compared with conventional roofs. One of the most critical steps in green roof installation is the selection of drought and heat tolerant species that can thrive under extreme microclimate conditions. We monitored the water status, growth and survival of 11 drought-adapted shrub species grown on shallow green roof modules (10 and 13cm deep substrate) and analyzed traits enabling plants to cope with drought (symplastic and apoplastic resistance) and heat stress (root membrane stability). The physiological traits conferring efficiency/safety to the water transport system under severe drought influenced plant water status and represent good predictors of both plant water use and growth rates over green roofs. Moreover, our data suggest that high substrate temperature represents a stress factor affecting plant survival to a larger extent than drought per se. In fact, the major cause influencing seedling survival on shallow substrates was the species-specific root resistance to heat, a single and easy measurable trait that should be integrated into the methodological framework for screening and selection of suitable shrub species for roof greening in the Mediterranean.

  3. Design and analysis of a cogeneration plant using heat recovery of a cement factory

    Directory of Open Access Journals (Sweden)

    G.V. Pradeep Varma

    2015-03-01

    Full Text Available There is a more potential in a cement factory for electric power generation using waste heat recovery compared to the other industries. A case study has been done at a cement factory having two units, 1600 TPD and 5500 TPD, identified three waste heat rejections at 176 °C, 330 °C and 420 °C and designed a suitable power plant configuration. In this work, an attempt has been made to quantify the power generation capacity with plant analysis. It has been resulted that 12.5 MW of power can be produced with the available heat recovery against a cement factory demand of 15 MW. The available process heat for cement production and power generation has been estimated at a capacity range from 5000 to 9000 TPD. The analysis recommended a low steam pressure for power generation at above said heat recovery gas temperature.

  4. Heat Shock Proteins: Old and Novel Roles in Neurodegenerative Diseases in the Central Nervous System.

    Science.gov (United States)

    van Noort, Johannes M; Bugiani, Marianna; Amor, Sandra

    2016-10-31

    Heat shock proteins (HSPs) are families of molecular chaperones that play important homeostatic functions in the central nervous system (CNS) by preventing protein misfolding, promoting degradation of improperly folded proteins, and protecting against apoptosis and inflammatory damage especially during hyperthermia, hypoxia, or oxidative stress. Under stress conditions, HSPs are upregulated to protect cells from damage that accumulates during ageing as well as pathological conditions. An important, yet frequently overlooked function of some HSPs is their ability to function as extracellular messengers (also termed chaperokines) that modulate immune responses within the CNS. Given the strong association between protein aggregation, innate immune cell activation and neurodegeneration, the expression and roles of HSPs in the CNS is attracting attention in many neurodegenerative disorders including inflammatory diseases such as multiple sclerosis, protein folding diseases such as Alzheimer's disease and amyotrophic lateral sclerosis, and genetic white matter diseases. This is especially so since several studies show that HSPs act therapeutically by modulating innate immune activation and may thus serve as neuroprotective agents. Here we review the evidence linking HSPs with neurodegenerative disorders in humans and the experimental animal models of these disorders. We discuss the mechanisms by which HSP protect cells, and how the knowledge of their endogenous functions can be exploited to treat disorders of the CNS.

  5. Micro bubble formation and bubble dissolution in domestic wet central heating systems

    Directory of Open Access Journals (Sweden)

    Ge Yunting

    2012-04-01

    Full Text Available 16 % of the carbon dioxide emissions in the UK are known to originate from wet domestic central heating systems. Contemporary systems make use of very efficient boilers known as condensing boilers that could result in efficiencies in the 90-100% range. However, research and development into the phenomenon of micro bubbles in such systems has been practically non-existent. In fact, such systems normally incorporate a passive deaerator that is installed as a ‘default’ feature with no real knowledge as to the micro bubble characteristics and their effect on such systems. High saturation ratios are known to occur due to the widespread use of untreated tap water in such systems and due to the inevitable leakage of air into the closed loop circulation system during the daily thermal cycling. The high temperatures at the boiler wall result in super saturation conditions which consequently lead to micro bubble nucleation and detachment, leading to bubbly two phase flow. Experiments have been done on a test rig incorporating a typical 19 kW domestic gas fired boiler to determine the expected saturation ratios and bubble production and dissolution rates in such systems.

  6. Micro bubble formation and bubble dissolution in domestic wet central heating systems

    Science.gov (United States)

    Fsadni, Andrew M.; Ge, Yunting

    2012-04-01

    16 % of the carbon dioxide emissions in the UK are known to originate from wet domestic central heating systems. Contemporary systems make use of very efficient boilers known as condensing boilers that could result in efficiencies in the 90-100% range. However, research and development into the phenomenon of micro bubbles in such systems has been practically non-existent. In fact, such systems normally incorporate a passive deaerator that is installed as a `default' feature with no real knowledge as to the micro bubble characteristics and their effect on such systems. High saturation ratios are known to occur due to the widespread use of untreated tap water in such systems and due to the inevitable leakage of air into the closed loop circulation system during the daily thermal cycling. The high temperatures at the boiler wall result in super saturation conditions which consequently lead to micro bubble nucleation and detachment, leading to bubbly two phase flow. Experiments have been done on a test rig incorporating a typical 19 kW domestic gas fired boiler to determine the expected saturation ratios and bubble production and dissolution rates in such systems.

  7. Exergy analysis of a combined heat and power plant with integrated lignocellulosic ethanol production

    DEFF Research Database (Denmark)

    Lythcke-Jørgensen, Christoffer Ernst; Haglind, Fredrik; Clausen, Lasse Røngaard

    2014-01-01

    production. An exergy analysis is carried out for a modelled polygeneration system in which lignocellulosic ethanol production based on hydrothermal pretreatment is integrated in an existing combined heat and power (CHP) plant. The ethanol facility is driven by steam extracted from the CHP unit when feasible...... in the ethanol facility. The calculated standard exergy efficiency of the ethanol facility varied from 0.564 to 0.855, of which the highest was obtained for integrated operation at reduced CHP load and full district heating production in the ethanol facility, and the lowest for separate operation with zero...

  8. Chromatin changes in response to drought, salinity, heat, and cold stresses in plants

    Directory of Open Access Journals (Sweden)

    Jong-Myong eKim

    2015-03-01

    Full Text Available Chromatin regulation is essential to regulate genes and genome activities. In plants, the alteration of histone modification and DNA methylation are coordinated with changes in the expression of stress-responsive genes to adapt to environmental changes. Several chromatin regulators have been shown to be involved in the regulation of stress-responsive gene networks under abiotic stress conditions. Specific histone modification sites and the histone modifiers that regulate key stress-responsive genes have been identified by genetic and biochemical approaches, revealing the importance of chromatin regulation in plant stress responses. Recent studies have also suggested that histone modification plays an important role in plant stress memory. In this review, we summarize recent progress on the regulation and alteration of histone modification (acetylation, methylation, phosphorylation, and SUMOylation in response to the abiotic stresses, drought, high-salinity, heat, and cold in plants.

  9. Distribution pattern and conservation of threatened medicinal and aromatic plants of Central Himalaya, India

    Institute of Scientific and Technical Information of China (English)

    L. S. Kandari; K.S. Rao; R. K. Maikhuri; G. Kharkwal; K. Chauhan; C.P. Kala

    2011-01-01

    A study was conducted to examine the distribution pattern of four rhizomatous medicinal and aromatic plant species (MAPs) viz., Angelica glauca, Pleurospermum angelicoides, Rheum emodi and Arne- bia benthamii in different forest stands in Central Himalaya. Results show that A. Glauca and P. Angelicoides had a higher (50%) frequency at Chipkoan, Garpak and Phagati forest, R. Emodi had a higher (60%) fre- quency at Rishikund, Suki and Himtoli, and A. Benthamii had a higher (70%) frequency at Suki and Khambdhar The densities of A. Glauca (0.6 plants·m) and P. Angelicoides (0.5 plants·m) were higher at Chipkoan and Garpak sites than at other micro-sites, while densities of R. Emodi (0.8 plants·m) and A. Benthamii (1.0 plants·m) were higher at Suki and Khambdhar sites. A. Glauca had highest total basal covers (TBC) (1.2 cm·m) at Chipkoan, P. Angelicoides had highest TBC (0.92 cm·m) at Lati kharak site, A. Benthamii had the highest TBC (6.48 cm·m) at Khambdhar, and R. Emodi had highest TBC (4.53 cm·m) at Rishikund. For the four studied species, A. Glauca showed a contagious distribution, P. Angelicoides and R. Emodi showed the random and A. Benthamii showed the regular type of distribution.

  10. A Qualitative Survey of Five Antibiotics in a Water Treatment Plant in Central Plateau of Iran

    Directory of Open Access Journals (Sweden)

    Mohsen Heidari

    2013-01-01

    Full Text Available Introduction. This study aimed to survey a total of five common human and veterinary antibiotics based on SPE-LC-MS-MS technology in a water treatment plant at central plateau of Iran. Also two sampling techniques, passive and grab samplings, were compared in the detection of selected antibiotics. Materials and Methods. In January to March 2012, grab and passive samples were taken from the influent and effluent of a water treatment plant. The samples were prepared using solid-phase extraction (SPE, and extracts were analyzed by liquid chromatography tandem mass spectrometry (LC-MS-MS. Results. The results showed that enrofloxacin, oxytetracycline, and tylosin were not detected in none of the samples. However, ampicillin was detected in the grab and passive samples taken from the influent (source water of the plant, and ciprofloxacin was detected in passive samples taken from the influent and effluent (finished water of the plant. Conclusion. The results imply that passive sampling is a better approach than grab sampling for the investigation of antibiotics in aquatic environments. The presence of ampicillin and ciprofloxacin in source water and finished water of the water treatment plant may lead to potential emergence of resistant bacteria that should be considered in future studies.

  11. A Central Role for Thiols in Plant Tolerance to Abiotic Stress

    Directory of Open Access Journals (Sweden)

    Lyuben Zagorchev

    2013-04-01

    Full Text Available Abiotic stress poses major problems to agriculture and increasing efforts are being made to understand plant stress response and tolerance mechanisms and to develop new tools that underpin successful agriculture. However, the molecular mechanisms of plant stress tolerance are not fully understood, and the data available is incomplete and sometimes contradictory. Here, we review the significance of protein and non-protein thiol compounds in relation to plant tolerance of abiotic stress. First, the roles of the amino acids cysteine and methionine, are discussed, followed by an extensive discussion of the low-molecular-weight tripeptide, thiol glutathione, which plays a central part in plant stress response and oxidative signalling and of glutathione-related enzymes, including those involved in the biosynthesis of non-protein thiol compounds. Special attention is given to the glutathione redox state, to phytochelatins and to the role of glutathione in the regulation of the cell cycle. The protein thiol section focuses on glutaredoxins and thioredoxins, proteins with oxidoreductase activity, which are involved in protein glutathionylation. The review concludes with a brief overview of and future perspectives for the involvement of plant thiols in abiotic stress tolerance.

  12. District heating and cooling systems for communities through power-plant retrofit and distribution network. Volume 2. Tasks 1-3. Final report. [Downtown Toledo steam system

    Energy Technology Data Exchange (ETDEWEB)

    Watt, J.R.; Sommerfield, G.A.

    1979-08-01

    Each of the tasks is described separately: Task 1 - Demonstration Team; Task 2 - Identify Thermal Energy Source(s) and Potential Service Area(s); and Task 3 - Energy Market Analysis. The purpose of the project is to establish and implement measures in the downtown Toledo steam system for conserving scarce fuel supplies through cogeneration, by retrofit of existing base- or intermediate-loaded electric-generating plants to provide for central heating and cooling systems, with the ultimate purpose of applying the results to other communities. For Task 1, Toledo Edison Company has organized a Demonstration Team (Battelle Columbus Laboratories; Stone and Webster; Ohio Dept. of Energy; Public Utilities Commission of Ohio; Toledo Metropolitan Area Council of Governments; and Toledo Edison) that it hopes has the expertise to evaluate the technical, legal, economic, and marketing issues related to the utilization of by-product heat from power generation to supply district heating and cooling services. Task 2 gives a complete technical description of the candidate plant(s), its thermodynamic cycle, role in load dispatch, ownership, and location. It is concluded that the Toledo steam distribution system can be the starting point for developing a new district-heating system to serve an expanding market. Battelle is a member of the team employed as a subcontractor to complete the energy market analysis. The work is summarized in Task 3. (MCW)

  13. Central African biomes and forest succession stages derived from modern pollen data and plant functional types

    Directory of Open Access Journals (Sweden)

    J. Lebamba

    2009-07-01

    Full Text Available New detailed vegetation reconstructions are proposed in Atlantic Central Africa from a modern pollen data set derived from 199 sites (Cameroon, Gabon and Congo including 131 new sites. In this study, the concept of plant functional classification is improved with new and more detailed plant functional types (PFTs and new aggregations of pollen taxa. Using the biomisation method, we reconstructed (1 modern potential biomes and (2 potential succession stages of forest regeneration, a new approach in Atlantic Central African vegetation dynamics and ecosystem functioning reconstruction. When compared to local vegetation, potential biomes are correctly reconstructed (97.5% of the sites and tropical rain forest (TRFO biome is well identified from tropical seasonal forest (TSFO biome. When the potential biomes are superimposed on the White's vegetation map, only 76.4% of the sites are correctly reconstructed. But using botanical data, correspondence and cluster analyses, the 43 sites from Congo (Mayombe evidence more affinities with those of central Gabon and so they can also be considered as correctly reconstructed as TRFO biome and White's map should be revised. In terms of potential succession stages of forest regeneration, the mature forest (TMFO is well differentiated from the secondary forest (TSFE, but inside this latter group, the young and the pioneer stages are not clearly identified due probably to their low sampling representation. Moreover, linked to their progressive and mosaic character, the boundaries between two forest biomes or two forest stages are not clearly detected and need also a more intensive sampling in such transitions.

  14. Direct Heat-Flux Measurement System (MDF) for Solar central Receiver Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Ballestrin, J.

    2001-07-01

    A direct flux measurement system, MDF, has been designed, constructed and mounted on top of the SSPS-CRS tower at the Plataforma Solar de Almeria (PSA) in addition to an indirect flux measurement system based on a CCD camera. It's one of the main future objectives to compare systematically both measurements of the concentrated solar power, increasing in this way the confidence in the estimate of this quantity. Today everything is prepared to perform the direct flux measurement on the aperture of solar receivers: calorimeter array, data acquisition system and software. the geometry of the receiver determines the operation and analysis procedures to obtain the indecent power onto the defined area. The study of previous experiences with direct flux measurement systems ha been useful to define a new simpler and more accurate system. A description of each component of the MDF system is included, focusing on the heat-flux sensors or calorimeters, which enables these measurements to be done in a few seconds without water-cooling. The incident solar power and the spatial flux distribution on the aperture of the volumetric receiver Hitrec II are supplied by the above-mentioned MDF system. The first results obtained during the evaluation of this solar receiver are presented including a sunrise-sunset test. All these measurements have been concentrated in one coefficient that describes the global behavior of the Solar Power Plant. (Author) 18 refs.

  15. Medicinal plants used by the Yi ethnic group: a case study in central Yunnan

    Directory of Open Access Journals (Sweden)

    Li Sumei

    2009-04-01

    Full Text Available Abstract Background This paper is based on ethnomedicinal investigation conducted from 1999–2002 in Chuxiong, central Yunnan Province, Southwest China. The Yi medicine has made a great contribution to the ethnomedicinal field in China. Neither case studies nor integrated inventories have previously been conducted to investigate the traditional Yi plants. This paper aims to argue the status and features of medicinal plants used in traditional Yi societies through a case study. Methods The approaches of ethnobotany, anthropology, and participatory rural appraisal were used in the field surveys. Twenty-two informants in four counties were interviewed during eight field trips. Medicinal plant specimens were identified according to taxonomic methods. Results One hundred sixteen medicinal plant species were found to be useful by the local people in the treatment of various diseases or disorders, especially those relating to trauma, gastrointestinal disorders and the common cold. Among these 116 species, 25 species (21.55% were found to have new curative effects and 40 species (34.48% were recorded for their new preparation methods; 55 different species were used in treating wounds and fractures, and 47 were used to treat gastrointestinal disorders. Traditional Yi herbal medicines are characterized by their numerous quantities of herbaceous plants and their common preparation with alcohol. Conclusion Totally 116 species in 58 families of medicinal plants traditionally used by the Yi people were inventoried and documented. The characteristics of medicinal plants were analyzed. Some new findings (such as new curative effects and new preparation methods were recorded These newly gathered ethnobotanical and medicinal data are precious sources for the future development of new drugs, and for further phytochemical, pharmacological and clinical studies.

  16. Special considerations on operating a fuel cell power plant using natural gas with marginal heating value

    Energy Technology Data Exchange (ETDEWEB)

    Moses, L. Ng; Chien-Liang Lin [Industrial Technology Research Institute, Taiwan (China); Ya-Tang Cheng [Power Research Institute, Taiwan (China)

    1996-12-31

    In realizing new power generation technologies in Taiwan, a phosphoric acid fuel cell power plant (model PC2513, ONSI Corporation) has been installed in the premises of the Power Research Institute of the Taiwan Power Company in Taipei County of Taiwan. The pipeline gas supplying to the site of this power plant has a high percentage of carbon dioxide and thus a slightly lower heating value than that specified by the manufacturer. Because of the lowering of heating value of input gas, the highest Output power from the power plant is understandably less than the rated power of 200 kW designed. Further, the transient response of the power plant as interrupted from the Grid is also affected. Since this gas is also the pipeline gas supplying to the heavily populated Taipei Municipal area, it is conceivable that the success of the operations of fuel cells using this fuel is of vital importance to the promotion of the use of this power generation technology in Taiwan. Hence, experiments were set up to assess the feasibility of this fuel cell power plant using the existing pipeline gas in this part of Taiwan where fuel cells would most likely find useful.

  17. New gasification plants for combined heat and power in Denmark; Nye forgasningsanlaeg til kraftvarme i Danmark

    Energy Technology Data Exchange (ETDEWEB)

    Houmoeller, S.

    1997-12-31

    In Danish energy planning, the role of combined heat and power generation has been increasing. This has aroused an interest in gasification of biofuels. Several gasification techniques are being developed and the focus is on wood rather than straw. This conference paper describes the present projects in this field and lists the advantages and disadvantages of each technique. The tar content of the gas is a problem. A recent attempt has been made to decompose the tar in biogas plants. Gasification plants are supposed to be commercially available within a few years

  18. Conservation potential at heating plants and cooling plants by means of regular jet plants; Einsparungspotential bei Heizungs- und Kaelteanlagen durch geregelte Strahlpumpen

    Energy Technology Data Exchange (ETDEWEB)

    Kilpper, Renate [W. Baelz und Sohn GmbH, Heilbronn (Germany)

    2009-12-15

    Regular jet pumps also are well-known as three-way injector valves. The employment of these regular jet pumps for the regulation of heating systems, ventilation systems and refrigerant plants in the industry and in the building engineering of hospitals, schools and administration buildings increases ever more. High savings of electricity and armatures are possible due to this technology. A selection of jet pumps with flange connections and sleeve connections is possible.

  19. Carbon emission impact on the operation of virtual power plant with combined heat and power system

    Institute of Scientific and Technical Information of China (English)

    Yu-hang XIA; Jun-yong LIU; Zheng-wen HUANG; Xu ZHANG

    2016-01-01

    A virtual power plant (VPP) can realize the aggregation of distributed generation in a certain region, and represent distributed generation to participate in the power market of the main grid. With the expansion of VPPs and ever-growing heat demand of consumers, managing the effect of fluctuations in the amount of available renewable resources on the operation of VPPs and maintaining an economical supply of electric power and heat energy to users have been important issues. This paper proposes the allocation of an electric boiler to realize wind power directly converted for supplying heat, which can not only overcome the limitation of heat output from a combined heat and power (CHP) unit, but also reduce carbon emissions from a VPP. After the electric boiler is considered in the VPP operation model of the combined heat and power system, a multi-objective model is built, which includes the costs of carbon emissions, total operation of the VPP and the electricity traded between the VPP and the main grid. The model is solved by the CPLEX package using the fuzzy membership function in Matlab, and a case study is pre-sented. The power output of each unit in the case study is analyzed under four scenarios. The results show that after carbon emission is taken into account, the output of low carbon units is significantly increased, and the allocation of an electric boiler can facilitate the maximum absorption of renewable energy, which also reduces carbon emissions from the VPP.

  20. An Optimal Control Approach for an Overall Cryogenic Plant Under Pulsed Heat Loads

    CERN Document Server

    Gómez Palacin, Luis; Blanco Viñuela, Enrique; Maekawa, Ryuji; Chalifour, Michel

    2015-01-01

    This work deals with the optimal management of a cryogenic plant composed by parallel refrigeration plants, which provide supercritical helium to pulsed heat loads. First, a data reconciliation approach is proposed to estimate precisely the refrigerator variables necessary to deduce the efficiency of each refrigerator. Second, taking into account these efficiencies, an optimal operation of the system is proposed and studied. Finally, while minimizing the power consumption of the refrigerators, the control system maintains stable operation of the cryoplant under pulsed heat loads. The management of the refrigerators is carried out by an upper control layer, which balances the relative production of cooling power in each refrigerator. In addition, this upper control layer deals with the mitigation of malfunctions and faults in the system. The proposed approach has been validated using a dynamic model of the cryoplant developed with EcosimPro software, based on first principles (mass and energy balances) and the...

  1. Numerical simulation on heat transfer characteristics of the storage tank for concentrating solar power plant

    Directory of Open Access Journals (Sweden)

    Qianjun Mao

    2016-06-01

    Full Text Available Concentrating solar power plant coupling with energy storage is a new and emerging technology, which can solve two issues, that is, low flux density and intermittent of solar energy. Heat transfer characteristics of the storage tank in this system have a key effect on the system’s efficiency and cost. In this article, the heat transfer performance of a phase change thermal storage tank has been proposed, and the temperature distribution and liquid fraction of phase change material in the tank has numerically been investigated. The results show that the temperature increases with the increasing charge time. The results also show that there is a phase change process at the charge time of 200 min, and no phase change for the charge time of 250 and 300 min. The results of this article can provide a reference for future design and optimal operation of the storage tank in concentrating solar power plant.

  2. Mangrove plants in coastal area of Central Java: 2. Floristic composition and vegetation structure

    Directory of Open Access Journals (Sweden)

    KUSUMO WINARNO

    2005-07-01

    Full Text Available The study was intended to observe the vegetation composition and structure of mangrove plants on southern and northern coast of Central Java Province. This research was conducted in July till December 2003, at 20 sites. Laboratory assay was done in Laboratory of Biology Department, Faculty of Mathematics and Natural Sciences, and Central Laboratory of Mathematics and Natural Sciences, Sebelas Maret University (UNS Surakarta. Data was collected by using belt transect method, from coast line into landward. The result indicated that in common, the trees strata which also have shoots strata and strata of germs (seedlings; and bushes strata which also have strata of germs (seedlings, if they were compared to the same species then their important value tend to be stable. So it was predictable that in the disturbance condition, the preservation of mangrove was guaranteed, as long as there was no great change on a broad scale.

  3. Torrefaction of invasive alien plants: Influence of heating rate and other conversion parameters on mass yield and higher heating value.

    Science.gov (United States)

    Mundike, Jhonnah; Collard, François-Xavier; Görgens, Johann F

    2016-06-01

    With the aim of controlling their proliferation, two invasive alien plants, Lantana camara (LC) and Mimosa pigra (MP), both widespread in Africa, were considered for torrefaction for renewable energy applications. Using thermogravimetric analysis, the influence of heating rate (HR: 2.18-19.82°Cmin(-1)) together with variable temperature and hold time on char yield and HHV (in a bomb calorimeter) were determined. Statistically significant effects of HR on HHV with optima at 10.5°Cmin(-1) for LC and 20°Cmin(-1) for MP were obtained. Increases of HHV up to 0.8MJkg(-1) or energy yield greater than 10%, together with a 3-fold reduction in torrefaction conversion time could be achieved by optimisation of HR. Analysis of the torrefaction volatiles by TG-MS showed that not only hemicelluloses, but also lignin conversion, could influence the optimum HR value.

  4. Analysis and simulation of the drying-air heating system of a Brazilian powdered milk plant

    Directory of Open Access Journals (Sweden)

    C. P. Ribeiro Jr.

    2004-06-01

    Full Text Available Aiming at simulating air-heating systems, two algorithms were developed for the calculation of finned elliptical-tube heat exchangers, whose basic difference lies in the kind of hot fluid employed: saturated steam or hot liquid. In both cases, a crossflow unit, in which the cold fluid is mixed and always flows on the shell side, is considered. The hot fluid may exhibit multiple passes in the tubes and is assumed unmixed, except for the region between the passes. A comparison between calculated results and operating data on industrial exchangers indicated the adequacy of the algorithms developed. The codes were then introduced into the ASPEN Plus shell, enabling simulation of the steady-state operation of the whole drying-air heating system of a powdered milk plant. Moreover, a sensitivity analysis of this system was conducted for one of its operating parameters and the existence of an optimal value for this variable was clearly shown.

  5. Elevating optimal human nutrition to a central goal of plant breeding and production of plant-based foods.

    Science.gov (United States)

    Sands, David C; Morris, Cindy E; Dratz, Edward A; Pilgeram, Alice

    2009-11-01

    High-yielding cereals and other staples have produced adequate calories to ward off starvation for much of the world over several decades. However, deficiencies in certain amino acids, minerals, vitamins and fatty acids in staple crops, and animal diets derived from them, have aggravated the problem of malnutrition and the increasing incidence of certain chronic diseases in nominally well-nourished people (the so-called diseases of civilization). Enhanced global nutrition has great potential to reduce acute and chronic disease, the need for health care, the cost of health care, and to increase educational attainment, economic productivity and the quality of life. However, nutrition is currently not an important driver of most plant breeding efforts, and there are only a few well-known efforts to breed crops that are adapted to the needs of optimal human nutrition. Technological tools are available to greatly enhance the nutritional value of our staple crops. However, enhanced nutrition in major crops might only be achieved if nutritional traits are introduced in tandem with important agronomic yield drivers, such as resistance to emerging pests or diseases, to drought and salinity, to herbicides, parasitic plants, frost or heat. In this way we might circumvent a natural tendency for high yield and low production cost to effectively select against the best human nutrition. Here we discuss the need and means for agriculture, food processing, food transport, sociology, nutrition and medicine to be integrated into new approaches to food production with optimal human nutrition as a principle goal.

  6. Design and thermal analysis of a direct steam generation central-receiver solar thermal power plant

    OpenAIRE

    Garrido Camino, Carlos

    2013-01-01

    Thermo-solar central receiver power plants use radiation coming from the Sun, a clean energy source, to produce electricity. The best locations for this type of installations are the ones between 30º and 40º of latitude, both in the northern and southern hemisphere, what makes Spain to be one of the most suitable and attractive places all over the world for this energy source. However, this technology is not well developed yet comparing to other renewable energy sources such as wind energy or...

  7. Isolation and identification mould micoflora inhabiting plant leaf litter from Mount Lawu, Surakarta, Central Java

    Directory of Open Access Journals (Sweden)

    MUHAMMAD ILYAS

    2007-04-01

    Full Text Available A study on isolation and identification mould inhabiting plant leaf litter had been conducted. The objective of the study was to isolate and identify mould inhabiting plant leaf litter from Mount Lawu, Surakarta, Central Java. The mould isolation was based on washing and filtering with membrane isolation method. The result showed that 39 moulds generas with 55 species varians, one group identified in class level, and three groups of unidentified mould isolates had been isolated. Taxas distributions showed that there were endophyte and phytopatogen mould isolates had been isolated such as Fusarium, Pestalotiopsis, Phoma, and Coelomycetes. However, typical soil taxa and common saprobic fungi such as Aspergillus, Cunninghamella, Mucor, Paecilomyces, Penicillium, Rhizopus, and Trichoderma remain dominated the resulted isolates.

  8. Investigation of heat exchangers for energy conversion systems of megawatt-class space power plants

    Science.gov (United States)

    Ilmov, D. N.; Mamontov, Yu. N.; Skorohodov, A. S.; Smolyarov, V. A.; Filatov, N. I.

    2016-01-01

    The specifics of operation (high temperatures in excess of 1000 K and large pressure drops of several megapascals between "hot" and "cold" coolant paths) of heat exchangers in the closed circuit of a gasturbine power converter operating in accordance with the Brayton cycle with internal heat recovery are analyzed in the context of construction of space propulsion systems. The design of a heat-exchange matrix made from doubly convex stamped plates with a specific surface relief is proposed. This design offers the opportunity to construct heat exchangers with the required parameters (strength, rigidity, weight, and dimensions) for the given operating conditions. The diagram of the working area of a test bench is presented, and the experimental techniques are outlined. The results of experimental studies of heat exchange and flow regimes in the models of heat exchangers with matrices containing 50 and 300 plates for two pairs of coolants (gas-gas and gas-liquid) are detailed. A criterion equation for the Nusselt number in the range of Reynolds numbers from 200 to 20 000 is proposed. The coefficients of hydraulic resistance for each coolant path are determined as functions of the Reynolds number. It is noted that the pressure in the water path in the "gas-liquid" series of experiments remained almost constant. This suggests that no well-developed processes of vaporization occurred within this heat-exchange matrix design even when the temperature drop between gas and water was as large as tens or hundreds of degrees. The obtained results allow one to design flight heat exchangers for various space power plants.

  9. Performance investigation of a cogeneration plant with the efficient and compact heat recovery system

    KAUST Repository

    Myat, Aung

    2011-10-03

    This paper presents the performance investigation of a cogeneration plant equipped with an efficient waste heat recovery system. The proposed cogeneration system produces four types of useful energy namely: (i) electricity, (ii) steam, (iii) cooling and (iv) dehumidification. The proposed plant comprises a Capstone C30 micro-turbine which generates 24 kW of electricity, a compact and efficient waste heat recovery system and a host of waste heat activated devices namely (i) a steam generator, (ii) an absorption chiller, (iii) an adsorption chiller and (iv) a multi-bed desiccant dehumidifier. The numerical analysis for the host of waste heat recovery system and thermally activated devices using FORTRAN power station linked to powerful IMSL library is performed to investigate the performance of the overall system. A set of experiments, both part load and full load, of micro-turbine is conducted to examine the electricity generation and the exhaust gas temperature. It is observed that energy utilization factor (EUF) could achieve as high as 70% while Fuel Energy Saving Ratio (FESR) is found to be 28%.

  10. Performance investigation of a cogeneration plant with the efficient and compact heat recovery system

    Science.gov (United States)

    Myat, Aung; Thu, Kyaw; Kim, Young-Deuk; Choon, Ng Kim

    2012-06-01

    This paper presents the performance investigation of a cogeneration plant equipped with an efficient waste heat recovery system. The proposed cogeneration system produces four types of useful energy namely: (i) electricity, (ii) steam, (iii) cooling and (iv) dehumidification. The proposed plant comprises a Capstone C30 micro-turbine which generates 24 kW of electricity, a compact and efficient waste heat recovery system and a host of waste heat activated devices namely (i) a steam generator, (ii) an absorption chiller, (iii) an adsorption chiller and (iv) a multi-bed desiccant dehumidifier. The numerical analysis for the host of waste heat recovery system and thermally activated devices using FORTRAN power station linked to powerful IMSL library is performed to investigate the performance of the overall system. A set of experiments, both part load and full load, of micro-turbine is conducted to examine the electricity generation and the exhaust gas temperature. It is observed that energy utilization factor (EUF) could achieve as high as 70% while Fuel Energy Saving Ratio (FESR) is found to be 28%.

  11. Effect of heating strategy on power consumption and performance of a pilot plant anaerobic digester.

    Science.gov (United States)

    Espinosa-Solares, Teodoro; Valle-Guadarrama, Salvador; Bombardiere, John; Domaschko, Max; Easter, Michael

    2009-05-01

    The effect of heating strategy on power consumption and performance of a pilot plant anaerobic digester treating chicken litter, under thermophilic conditions, has been studied. Heating strategy was evaluated using three different spans (0.2 degrees C, 0.6 degrees C, and 1.0 degree C) for triggering the temperature control system from target temperature (56.7 degrees C). The hydraulic retention time in the pilot plant digester was in the range of 32 to 37 days, varying the total solids concentration fed from 5% to 6%. The results showed that under the experimental conditions, heating was the most energy-demanding process with 95.5% of the energy used. Increments up to 7.5% and 3.8%, respectively, on mechanical and heating power consumption, were observed as the span, for triggering the temperature control system from target temperature, was increased. Under the experimental conditions studied here, an increment of 30.6% on the global biodigester performance index was observed when a span of 1.0 degree C was compared to the one of 0.2 degrees C.

  12. Agave salmiana Plant Communities in Central Mexico as Affected by Commercial Use

    Science.gov (United States)

    Martínez Salvador, Martin; Mata-González, Ricardo; Morales Nieto, Carlos; Valdez-Cepeda, Ricardo

    2012-01-01

    Agave salmiana is a native plant species harvested for the commercial production of mezcal ( Agave spirits) in the highlands of central Mexico. The objective of this study was to identify vegetation changes in natural communities where A. salmiana has been differentially harvested for commercial purposes. Three plant community categories were identified in the state of Zacatecas based on their history of A. salmiana utilization: short (less than 10 years of use), moderate (about 25 years), and long (60 or more years). Species cover, composition, and density were evaluated in field surveys by use category. A gradient of vegetation structure of the communities parallels the duration of A. salmiana use. A. salmiana density was greatest (3,125 plants ha-1) in the short-use areas and less (892 plants ha-1) in the moderate-use areas, associated with markedly greater density of shrubs (200%) and Opuntia spp. (50%) in moderate-use areas. The main shrubs were Larrea tridentata, Mimosa biuncifera, Jatropha dioica and Buddleia scordioides while the main Opuntia species were Opuntia leucotricha and Opuntia robusta. A. salmiana density was least (652 plants ha-1) in the long-use areas where shrubs were less abundant but Opuntia spp. density was 25% higher than in moderate-use areas. We suggest that shrubs may increase with moderate use creating an intermediate successional stage that facilitates the establishment of Opuntia spp. Long-term Agave use is generating new plant communities dominated by Opuntia spp. (nopaleras) as a replacement of the original communities dominated by A. salmiana (magueyeras).

  13. Agave salmiana plant communities in central Mexico as affected by commercial use.

    Science.gov (United States)

    Martínez Salvador, Martin; Mata-González, Ricardo; Morales Nieto, Carlos; Valdez-Cepeda, Ricardo

    2012-01-01

    Agave salmiana is a native plant species harvested for the commercial production of mezcal (Agave spirits) in the highlands of central Mexico. The objective of this study was to identify vegetation changes in natural communities where A. salmiana has been differentially harvested for commercial purposes. Three plant community categories were identified in the state of Zacatecas based on their history of A. salmiana utilization: short (less than 10 years of use), moderate (about 25 years), and long (60 or more years). Species cover, composition, and density were evaluated in field surveys by use category. A gradient of vegetation structure of the communities parallels the duration of A. salmiana use. A. salmiana density was greatest (3,125 plants ha(-1)) in the short-use areas and less (892 plants ha(-1)) in the moderate-use areas, associated with markedly greater density of shrubs (200%) and Opuntia spp. (50%) in moderate-use areas. The main shrubs were Larrea tridentata, Mimosa biuncifera, Jatropha dioica and Buddleia scordioides while the main Opuntia species were Opuntia leucotricha and Opuntia robusta. A. salmiana density was least (652 plants ha(-1)) in the long-use areas where shrubs were less abundant but Opuntia spp. density was 25% higher than in moderate-use areas. We suggest that shrubs may increase with moderate use creating an intermediate successional stage that facilitates the establishment of Opuntia spp. Long-term Agave use is generating new plant communities dominated by Opuntia spp. (nopaleras) as a replacement of the original communities dominated by A. salmiana (magueyeras).

  14. Evaluation and demonstration of decentralized space and water heating versus centralized services for new and rehabilitated multifamily buildings. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Belkus, P. [Foster-Miller, Inc., Waltham, MA (US); Tuluca, A. [Steven Winter Associates, Inc., Norwalk, CT (US)

    1993-06-01

    The general objective of this research was aimed at developing sufficient technical and economic know-how to convince the building and design communities of the appropriateness and energy advantages of decentralized space and water heating for multifamily buildings. Two main goals were established to guide this research. First, the research sought to determine the cost-benefit advantages of decentralized space and water heating versus centralized systems for multifamily applications based on innovative gas piping and appliance technologies. The second goal was to ensure that this information is made available to the design community.

  15. Ozone pollution during heat wave periods over last 15 years in Central Europe

    Science.gov (United States)

    Struzewska, J.; Kaminski, J. W.; Jefimow, M.

    2012-04-01

    Periods characterized with the high ozone concentrations are usually associated with very high air temperature and antycyclonic conditions or meridional circulation. A 15-year (1997 - 2011) maximum daily temperature records from GSOD NOAA archive was analyzed for 20 stations in Central Europe. For each year the number of days with the maximum temperature exceeding 25oC and 30oC was calculated. For years with a positive anomaly of the number of the hot days the data were analyzed to identify exact dates and the duration of such events. This allows classification of the high temperature period as "heat waves" (periods with maximum temperature exceeding 30oC lasting at least 3 consecutive days) and hot weather periods (periods with maximum temperature exceeding 25oC and high daily average temperature). These two types of high temperature are usually associated with different air masses inflow - subtropical from the south or transformed polar from westerly directions. This indicates also the differences in contribution of transboundary transport of ozone and its precursors. For selected high temperature episodes the ozone pollution was assessed based on AirBase (1997-2009) and national database (2010-2011). The analysis covered the 8-hour running average and daily maximum concentration of ozone near the surface. Also, the contribution to the SOMO35 index during selected episodes will be calculated as a diagnostic for adverse health effects. Since the two analyzed types of hot weather periods have different origin in terms of synoptic scale situation, an attempt will be made to answer whether there are differences in the intensity of ozone episodes during selected hot weather periods. The outcome from the study will be useful for the interpretation of modelling results for air quality in future climate.

  16. Wastewater treatment plant in Buholz, Lucerne: operational optimisation of a combined heat and power unit, remote heating for RUAG Aerospace; ARA Buholz, 6000 Luzern. Betriebsoptimierung BHKW. Fernwaermeleitung RUAG Aerospace

    Energy Technology Data Exchange (ETDEWEB)

    Christen, R.

    2004-07-01

    This preliminary report for the Swiss Federal Office of Energy (SFOE) presents the results of a study made on the use of sewage gas generated at central Switzerland's largest wastewater treatment and sludge incineration plant. Experience gained with the previously used combined heat and power (CHP) unit and the use of gas in a heating boiler is looked at. Operational experience gained after the implementation of a first set of measures is commented on. The optimisation measures taken are discussed and the use of waste heat to provide energy for a nearby facility of the RUAG Aerospace company is described. The report also describes a catalyzer system installed in a second phase of the project to clean the waste gas from the sludge incineration plant. Also, the system used for the preparation of the sewage gas to make it suitable for injection into the local natural gas mains is described. The results of measurements made on the success of the project are presented and commented on and the ecological profits of the plant are discussed.

  17. Central heating in Norway. A study of the market trends for the period 2008-2011; Vannbaaren varme i Norge. Et studium av markedsutviklingen i perioden 2008-2011

    Energy Technology Data Exchange (ETDEWEB)

    Haarberg, Karl Johan; Hansen, Eivind; Bjoerneng, Heidi; Vasvik, Truls

    2012-11-01

    Under floor heating distribution buildings gives the flexibility to accept multiple forms of renewable energy, whether from district heating, biomass, solar collectors or heat pumps. Central heating is therefore a joker for a flexible energy. This is why Prognosesenteret commissioned by Enova has conducted a survey on central heating systems aimed at plumbers over a 5-year period. (eb)

  18. The Photovoltaic Heat Island Effect: Larger solar power plants increase local temperatures

    Science.gov (United States)

    Barron-Gafford, Greg A.; Minor, Rebecca L.; Allen, Nathan A.; Cronin, Alex D.; Brooks, Adria E.; Pavao-Zuckerman, Mitchell A.

    2016-01-01

    While photovoltaic (PV) renewable energy production has surged, concerns remain about whether or not PV power plants induce a “heat island” (PVHI) effect, much like the increase in ambient temperatures relative to wildlands generates an Urban Heat Island effect in cities. Transitions to PV plants alter the way that incoming energy is reflected back to the atmosphere or absorbed, stored, and reradiated because PV plants change the albedo, vegetation, and structure of the terrain. Prior work on the PVHI has been mostly theoretical or based upon simulated models. Furthermore, past empirical work has been limited in scope to a single biome. Because there are still large uncertainties surrounding the potential for a PHVI effect, we examined the PVHI empirically with experiments that spanned three biomes. We found temperatures over a PV plant were regularly 3–4 °C warmer than wildlands at night, which is in direct contrast to other studies based on models that suggested that PV systems should decrease ambient temperatures. Deducing the underlying cause and scale of the PVHI effect and identifying mitigation strategies are key in supporting decision-making regarding PV development, particularly in semiarid landscapes, which are among the most likely for large-scale PV installations. PMID:27733772

  19. The Photovoltaic Heat Island Effect: Larger solar power plants increase local temperatures.

    Science.gov (United States)

    Barron-Gafford, Greg A; Minor, Rebecca L; Allen, Nathan A; Cronin, Alex D; Brooks, Adria E; Pavao-Zuckerman, Mitchell A

    2016-10-13

    While photovoltaic (PV) renewable energy production has surged, concerns remain about whether or not PV power plants induce a "heat island" (PVHI) effect, much like the increase in ambient temperatures relative to wildlands generates an Urban Heat Island effect in cities. Transitions to PV plants alter the way that incoming energy is reflected back to the atmosphere or absorbed, stored, and reradiated because PV plants change the albedo, vegetation, and structure of the terrain. Prior work on the PVHI has been mostly theoretical or based upon simulated models. Furthermore, past empirical work has been limited in scope to a single biome. Because there are still large uncertainties surrounding the potential for a PHVI effect, we examined the PVHI empirically with experiments that spanned three biomes. We found temperatures over a PV plant were regularly 3-4 °C warmer than wildlands at night, which is in direct contrast to other studies based on models that suggested that PV systems should decrease ambient temperatures. Deducing the underlying cause and scale of the PVHI effect and identifying mitigation strategies are key in supporting decision-making regarding PV development, particularly in semiarid landscapes, which are among the most likely for large-scale PV installations.

  20. The Photovoltaic Heat Island Effect: Larger solar power plants increase local temperatures

    Science.gov (United States)

    Barron-Gafford, Greg A.; Minor, Rebecca L.; Allen, Nathan A.; Cronin, Alex D.; Brooks, Adria E.; Pavao-Zuckerman, Mitchell A.

    2016-10-01

    While photovoltaic (PV) renewable energy production has surged, concerns remain about whether or not PV power plants induce a “heat island” (PVHI) effect, much like the increase in ambient temperatures relative to wildlands generates an Urban Heat Island effect in cities. Transitions to PV plants alter the way that incoming energy is reflected back to the atmosphere or absorbed, stored, and reradiated because PV plants change the albedo, vegetation, and structure of the terrain. Prior work on the PVHI has been mostly theoretical or based upon simulated models. Furthermore, past empirical work has been limited in scope to a single biome. Because there are still large uncertainties surrounding the potential for a PHVI effect, we examined the PVHI empirically with experiments that spanned three biomes. We found temperatures over a PV plant were regularly 3–4 °C warmer than wildlands at night, which is in direct contrast to other studies based on models that suggested that PV systems should decrease ambient temperatures. Deducing the underlying cause and scale of the PVHI effect and identifying mitigation strategies are key in supporting decision-making regarding PV development, particularly in semiarid landscapes, which are among the most likely for large-scale PV installations.

  1. Design of Biomass Gasification and Combined Heat and Power Plant Based on Laboratory Experiments

    Science.gov (United States)

    Haydary, Juma; Jelemenský, Ľudovít

    Three types of wooden biomass were characterized by calorimetric measurements, proximate and elemental analysis, thermogravimetry, kinetics of thermal decomposition and gas composition. Using the Aspen steady state simulation, a plant with the processing capacity of 18 ton/h of biomass was modelled based on the experimental data obtained under laboratory conditions. The gasification process has been modelled in two steps. The first step of the model describes the thermal decomposition of the biomass based on a kinetic model and in the second step, the equilibrium composition of syngas is calculated by the Gibbs free energy of the expected components. The computer model of the plant besides the reactor model includes also a simulation of other plant facilities such as: feed drying employing the energy from the process, ash and tar separation, gas-steam cycle, and hot water production heat exchangers. The effect of the steam to air ratio on the conversion, syngas composition, and reactor temperature was analyzed. Employment of oxygen and air for partial combustion was compared. The designed computer model using all Aspen simulation facilities can be applied to study different aspects of biomass gasification in a Combined Heat and Power plant.

  2. Application of artificial neural networks to the condition monitoring and diagnosis of a combined heat and power plant

    Energy Technology Data Exchange (ETDEWEB)

    Fast, M. [Division of Thermal Power Engineering, Department of Energy Sciences, Lund University, P.O. Box 118, S-221 00 Lund (Sweden); Palme, T. [Department of Mechanical and Structural Engineering and Materials Science, University of Stavanger, N-4036 Stavanger (Norway)

    2010-02-15

    The objective of this study has been to create an online system for condition monitoring and diagnosis of a combined heat and power plant in Sweden. The system in question consisted of artificial neural network models, representing each main component of the combined heat and power plant, connected to a graphical user interface. The artificial neural network models were integrated on a power generation information manager server in the computer system of the combined heat and power plant, and the graphical user interface was made available on workstations connected to this server. The plant comprised a Siemens SGT800 gas turbine with a heat recovery steam generator as well as a bio-fueled boiler and its steam cycle. Steam from the heat recovery steam generator and the bio-fueled boiler expanded together in a common steam turbine, producing both electricity and heat. The artificial neural network models were trained with operational data from the components of the combined heat and power plant. Accurate predictions from the ANN (Artificial neural network) models in combination with an undemanding integration in the power plant's computer system were some of the main conclusions from this study. (author)

  3. Lifetime of solar collectors in solar heating plants; Levetid for solfangere i solvarmecentraler

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Z.; Fan, J.; Perers, B.; Furbo, S.

    2009-10-15

    Two HT solar collectors, which have been in operation at high temperature levels in Ottrupgaard solar heating plant for 15 years and in Marstal solar heating plant for 13 years, were in the spring of 2009 tested with regard to efficiency. The collectors were also inspected with the aim to evaluate the life time of the collectors. An old version of the HT solar collector, which has been in operation in a Swedish test facility since 1982, was tested with regard to the thermal performance. The measurements showed that the efficiencies of the solar collectors from the two Danish solar heating plants have been decreased since the installation. The reductions of the yearly thermal performance of the solar collectors are at a temperature level of 40 centigrade Celsius, 1% and 4%, respectively, for the Marstal collector and the Ottrupgaard collector. At a temperature level of 60 centigrade Celsius the reduction of the yearly thermal performance is 10% and 11%, respectively, for the Marstal collector and the Ottrupgaard collector. At a temperature level of 80 centigrade Celsius the reduction is 27% and 23%, respectively, for the Marstal collector and the Ottrupgaard collector. Based on the inspection, it is estimated that the reason for the reduction of thermal performance is the condition of the Teflon foil and the installation of the Teflon foil. The Teflon foil is wrinkled and folded and expanded in such a way that the distance between the absorber and the Teflon foil is far too small. Further, cracks in the Teflon foil have been observed. The thermal performance of the Swedish solar collector in the test facility is after 26 years of operation reduced compared to the thermal performance of the collector when it was first installed. For this collector the reduction in thermal performance is only 2-5%. The collectors from Ottrupgaard solar heating plant and from Marstal solar heating plant were in a very good condition with exception of the above mentioned problems with

  4. Heat shock protein 90 in plants: molecular mechanisms and roles in stress responses.

    Science.gov (United States)

    Xu, Zhao-Shi; Li, Zhi-Yong; Chen, Yang; Chen, Ming; Li, Lian-Cheng; Ma, You-Zhi

    2012-11-23

    The heat shock protein 90 (Hsp90) family mediates stress signal transduction, and plays important roles in the control of normal growth of human cells and in promoting development of tumor cells. Hsp90s have become a currently important subject in cellular immunity, signal transduction, and anti-cancer research. Studies on the physiological functions of Hsp90s began much later in plants than in animals and fungi. Significant progress has been made in understanding complex mechanisms of HSP90s in plants, including ATPase-coupled conformational changes and interactions with cochaperone proteins. A wide range of signaling proteins interact with HSP90s. Recent studies revealed that plant Hsp90s are important in plant development, environmental stress response, and disease and pest resistance. In this study, the plant HSP90 family was classified into three clusters on the basis of phylogenetic relationships, gene structure, and biological functions. We discuss the molecular functions of Hsp90s, and systematically review recent progress of Hsp90 research in plants.

  5. Impact of plant shoot architecture on leaf cooling: a coupled heat and mass transfer model.

    Science.gov (United States)

    Bridge, L J; Franklin, K A; Homer, M E

    2013-08-01

    Plants display a range of striking architectural adaptations when grown at elevated temperatures. In the model plant Arabidopsis thaliana, these include elongation of petioles, and increased petiole and leaf angles from the soil surface. The potential physiological significance of these architectural changes remains speculative. We address this issue computationally by formulating a mathematical model and performing numerical simulations, testing the hypothesis that elongated and elevated plant configurations may reflect a leaf-cooling strategy. This sets in place a new basic model of plant water use and interaction with the surrounding air, which couples heat and mass transfer within a plant to water vapour diffusion in the air, using a transpiration term that depends on saturation, temperature and vapour concentration. A two-dimensional, multi-petiole shoot geometry is considered, with added leaf-blade shape detail. Our simulations show that increased petiole length and angle generally result in enhanced transpiration rates and reduced leaf temperatures in well-watered conditions. Furthermore, our computations also reveal plant configurations for which elongation may result in decreased transpiration rate owing to decreased leaf liquid saturation. We offer further qualitative and quantitative insights into the role of architectural parameters as key determinants of leaf-cooling capacity.

  6. Heat Shock Protein 90 in Plants: Molecular Mechanisms and Roles in Stress Responses

    Directory of Open Access Journals (Sweden)

    You-Zhi Ma

    2012-11-01

    Full Text Available The heat shock protein 90 (Hsp90 family mediates stress signal transduction, and plays important roles in the control of normal growth of human cells and in promoting development of tumor cells. Hsp90s have become a currently important subject in cellular immunity, signal transduction, and anti-cancer research. Studies on the physiological functions of Hsp90s began much later in plants than in animals and fungi. Significant progress has been made in understanding complex mechanisms of HSP90s in plants, including ATPase-coupled conformational changes and interactions with cochaperone proteins. A wide range of signaling proteins interact with HSP90s. Recent studies revealed that plant Hsp90s are important in plant development, environmental stress response, and disease and pest resistance. In this study, the plant HSP90 family was classified into three clusters on the basis of phylogenetic relationships, gene structure, and biological functions. We discuss the molecular functions of Hsp90s, and systematically review recent progress of Hsp90 research in plants.

  7. Correct safety requirements during the life cycle of heating plants; Korrekta saekerhetskrav under vaermeanlaeggningars livscykel

    Energy Technology Data Exchange (ETDEWEB)

    Tegehall, Jan; Hedberg, Johan [Swedish National Testing and Research Inst., Boraas (Sweden)

    2006-10-15

    The safety of old steam boilers or hot water generators is in principle based on electromechanical components which are generally easy to understand. The use of safety-PLC is a new and flexible way to design a safe system. A programmable system offers more degrees of freedom and consequently new problems may arise. As a result, new standards which use the Safety Integrity Level (SIL) concept for the level of safety have been elaborated. The goal is to define a way of working to handle requirements on safety in control systems of heat and power plants. SIL-requirements are relatively new within the domain and there is a need for guidance to be able to follow the requirements. The target of this report is the people who work with safety questions during new construction, reconstruction, or modification of furnace plants. In the work, the Pressure Equipment Directive, 97/23/EC, as well as standards which use the SIL concept have been studied. Additionally, standards for water-tube boilers have been studied. The focus has been on the safety systems (safety functions) which are used in water-tube boilers for heat and power plants; other systems, which are parts of these boilers, have not been considered. Guidance has been given for the aforementioned standards as well as safety requirements specification and risk analysis. An old hot water generator and a relatively new steam boiler have been used as case studies. The design principles and safety functions of the furnaces have been described. During the risk analysis important hazards were identified. A method for performing a risk analysis has been described and the appropriate content of a safety requirements specification has been defined. If a heat or power plant is constructed, modified, or reconstructed, a safety life cycle shall be followed. The purpose of the safety life cycle is to plan, describe, document, perform, check, test, and validate that everything is correctly done. The components of the safety

  8. Exergoeconomic performance optimization of an endoreversible intercooled regenerative Brayton combined heat and power plant coupled to variable-temperature heat reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Bo; Chen, Lingen; Sun, Fengrui [College of Naval Architecture and Power, Naval University of Engineering, Wuhan 430033 (China)

    2012-07-01

    An endoreversible intercooled regenerative Brayton combined heat and power (CHP) plant model coupled to variable-temperature heat reservoirs is established. The exergoeconomic performance of the CHP plant is investigated using finite time thermodynamics. The analytical formulae about dimensionless profit rate and exergy efficiency of the CHP plant with the heat resistance losses in the hot-, cold- and consumer-side heat exchangers, the intercooler and the regenerator are deduced. By taking the maximum profit rate as the objective, the heat conductance allocation among the five heat exchangers and the choice of intercooling pressure ratio are optimized by numerical examples, the characteristic of the optimal dimensionless profit rate versus corresponding exergy efficiency is investigated. When the optimization is performed further with respect to the total pressure ratio, a double-maximum profit rate is obtained. The effects of the design parameters on the double-maximum dimensionless profit rate and corresponding exergy efficiency, optimal total pressure ratio and optimal intercooling pressure ratio are analyzed in detail, and it is found that there exist an optimal consumer-side temperature and an optimal thermal capacitance rate matching between the working fluid and the heat reservoir, respectively, corresponding to a thrice-maximum dimensionless profit rate.

  9. Exergoeconomic performance optimization of an endoreversible intercooled regenerative Brayton combined heat and power plant coupled to variable-temperature heat reservoirs

    Directory of Open Access Journals (Sweden)

    Bo Yang, Lingen Chen, Fengrui Sun

    2012-01-01

    Full Text Available An endoreversible intercooled regenerative Brayton combined heat and power (CHP plant model coupled to variable-temperature heat reservoirs is established. The exergoeconomic performance of the CHP plant is investigated using finite time thermodynamics. The analytical formulae about dimensionless profit rate and exergy efficiency of the CHP plant with the heat resistance losses in the hot-, cold- and consumer-side heat exchangers, the intercooler and the regenerator are deduced. By taking the maximum profit rate as the objective, the heat conductance allocation among the five heat exchangers and the choice of intercooling pressure ratio are optimized by numerical examples, the characteristic of the optimal dimensionless profit rate versus corresponding exergy efficiency is investigated. When the optimization is performed further with respect to the total pressure ratio, a double-maximum profit rate is obtained. The effects of the design parameters on the double-maximum dimensionless profit rate and corresponding exergy efficiency, optimal total pressure ratio and optimal intercooling pressure ratio are analyzed in detail, and it is found that there exist an optimal consumer-side temperature and an optimal thermal capacitance rate matching between the working fluid and the heat reservoir, respectively, corresponding to a thrice-maximum dimensionless profit rate.

  10. Robustness analysis of an air heating plant and control law by using polynomial chaos

    Energy Technology Data Exchange (ETDEWEB)

    Colón, Diego [University of São Paulo, Polytechnic School, LAC -PTC, São Paulo (Brazil); Ferreira, Murillo A. S.; Bueno, Átila M. [São Paulo State University - Sorocaba Campus, Sorocaba (Brazil); Balthazar, José M. [São Paulo State University - Rio Claro Campus, Rio Claro (Brazil); Rosa, Suélia S. R. F. de [University of Brasilia, Brasilia (Brazil)

    2014-12-10

    This paper presents a robustness analysis of an air heating plant with a multivariable closed-loop control law by using the polynomial chaos methodology (MPC). The plant consists of a PVC tube with a fan in the air input (that forces the air through the tube) and a mass flux sensor in the output. A heating resistance warms the air as it flows inside the tube, and a thermo-couple sensor measures the air temperature. The plant has thus two inputs (the fan's rotation intensity and heat generated by the resistance, both measured in percent of the maximum value) and two outputs (air temperature and air mass flux, also in percent of the maximal value). The mathematical model is obtained by System Identification techniques. The mass flux sensor, which is nonlinear, is linearized and the delays in the transfer functions are properly approximated by non-minimum phase transfer functions. The resulting model is transformed to a state-space model, which is used for control design purposes. The multivariable robust control design techniques used is the LQG/LTR, and the controllers are validated in simulation software and in the real plant. Finally, the MPC is applied by considering some of the system's parameters as random variables (one at a time, and the system's stochastic differential equations are solved by expanding the solution (a stochastic process) in an orthogonal basis of polynomial functions of the basic random variables. This method transforms the stochastic equations in a set of deterministic differential equations, which can be solved by traditional numerical methods (That is the MPC). Statistical data for the system (like expected values and variances) are then calculated. The effects of randomness in the parameters are evaluated in the open-loop and closed-loop pole's positions.

  11. Optimization of Combine Heat and Power Plants in the Russian Wholesale Power Market Conditions

    Directory of Open Access Journals (Sweden)

    I. A. Chuchueva

    2015-01-01

    Full Text Available The paper concerns the relevant problem to optimize the combine heat and power (CHP plants in the Russian wholesale power market conditions. Since 1975 the CHP plants specialists faced the problem of fuel rate or fuel cost reduction while ensuring the fixed level of heat and power production. The optimality criterion was the fuel rate or fuel cost which has to be minimized. Produced heat and power was paid by known tariff. Since the power market started in 2006 the power payment scheme has essentially changed: produced power is paid by market price. In such condition a new optimality criterion the paper offers is a profit which has to be maximized for the given time horizon. Depending on the optimization horizon the paper suggests four types of the problem urgency, namely: long-term, mid-term, short-term, and operative optimization. It clearly shows that the previous problem of fuel cost minimization is a special case of profit maximization problem. To bring the problem to the mixed-integer linear programming problem a new linear characteristic curves of steam and gas turbine are introduced. Error of linearization is 0.6%. The formal statement of the problem of short-term CHP plants optimization in the market conditions is offered. The problem was solved with IRM software (OpenLinkInternational for seven power plants of JSC “Quadra”: Dyagilevskaya CHP, Kurskaya CHP-1, Lipetskaya CHP-2, Orlovskaya CHP, Kurskaya CHP NWR, Tambovskaya CHP, and Smolenskaya CHP-2.The conducted computational experiment showed that a potential profit is between 1.7% and 4.7% of the fuel cost of different CHP plants and depends on the power plant operation conditions. The potential profit value is 2–3 times higher than analogous estimations, which were obtained solving fuel cost minimization problem. The perspectives of the work are formalization of mid-term and long-term CHP plants optimization problem and development of domestic software for the new problem

  12. Combined heat and power plants with parallel tandem steam turbines; Smaaskalig kraftvaerme med parallellkopplade tandemturbiner

    Energy Technology Data Exchange (ETDEWEB)

    Steinwall, Pontus; Norstroem, Urban; Pettersson, Camilla; Oesterlin, Erik

    2004-12-01

    We investigate the technical and economical conditions for a concept with parallel coupled tandem turbines in small scale combined heat and power plants fired with bio-fuel and waste. Performance and heat production costs at varying electricity prices for the concept with two smaller tandem coupled steam turbines has been compared to the traditional concept with one single multi-staged turbine. Three different types of plants have been investigated: - Bio fuelled CHP plant with thermal capacity of 15 MW{sub th}; - Waste fired CHP plant with thermal capacity of 20 MW{sub th}; - Bio fuelled CHP plant with thermal capacity of 25 MW{sub th}. The simple steam turbines (Curtis turbines) used in the tandem arrangement has an isentropic efficiency of about 49 to 53% compared to the multi-staged steam turbines with isentropic efficiency in the range of 59% to 81%. The lower isentropic efficiency for the single staged turbines is to some extent compensated at partial load when one of the two turbines can be shut down leading to better operational conditions for the one still in operation. For concepts with saturated steam at partial load below 50% the tandem arrangements presents higher electricity efficiency than the conventional single turbine alternative. The difference in annual production of electricity is therefore less than the difference in isentropic efficiency for the two concepts. Production of electricity is between 2% and 42% lower for the tandem arrangements in this study. Investment costs for the turbine island has been calculated for the two turbine concepts and when the costs for turbines, generator, power transmission, condensing system, piping system, buildings, assembling, commissioning and engineering has been added the sum is about the same for the two concepts. For the bio-fuelled plant with thermal capacity of 15 MW{sub th} the turbine island amount to about 10-12 MSEK and about 13-15 MSEK for the waste fired plant with a thermal capacity of 20 MW

  13. Technology data for energy plants. Individual heating plants and energy transport

    Energy Technology Data Exchange (ETDEWEB)

    2012-05-15

    The present technology catalogue is published in co-operation between the Danish Energy Agency and Energinet.dk and includes technology descriptions for a number of technologies for individual heat production and energy transport. The primary objective of the technology catalogue is to establish a uniform, commonly accepted and up-to-date basis for the work with energy planning and the development of the energy sector, including future outlooks, scenario analyses and technical/economic analyses. The technology catalogue is thus a valuable tool in connection with energy planning and assessment of climate projects and for evaluating the development opportunities for the energy sector's many technologies, which can be used for the preparation of different support programmes for energy research and development. The publication of the technology catalogue should also be viewed in the light of renewed focus on strategic energy planning in municipalities etc. In that respect, the technology catalogue is considered to be an important tool for the municipalities in their planning efforts. (LN)

  14. A Novel approach for Low temperature Condenser waste heat Utilization in winter air conditioning for overall Performance Improvement of a Power Plant in Northern India

    Directory of Open Access Journals (Sweden)

    Rajendra Kumar Yadav

    2014-10-01

    Full Text Available The objective of this paper to highlight the scope of utilization of waste heat of condenser for winter air conditioning in and around thermal power stations. The vast amount of low grade condenser waste heat can be used to provide winter air conditioning by utilizing the existing system of year round central air conditioning without additional heavy capital expenditure .The present case study is about North India where peak winter lasts about 90 days . The waste heat utilization for winter conditioning will not only save large amount of electrical energy being used in electrical heaters but also generate additional revenue by selling out extra/spared power ,increase thermal energy utilization ,improve performance of the plant .The novel method of winter air conditioning will also reduce the heat load of the cooling towers, avoid pumping and blow down power as the returning water from air conditioning system can be used as blow down to maintain cooling water parameters in the plant.

  15. Plant biodiversity of beech forests in central-northern Italy: a methodological approach for conservation purposes

    Directory of Open Access Journals (Sweden)

    Marcantonio M

    2012-07-01

    Full Text Available Forests are reckoned essentials as biodiversity reservoirs and carbon sinks. Current threats to forest ecosystems (e.g., climate changes, habitat loss and fragmentation, management changes call for monitoring their biodiversity and preserving their ecological functions. In this study, we characterized plants diversity of five beech forests located in central and north Apennines mountain chain, using results by a probabilistic sampling. In order to achieve our goals, we have considered species richness and abundance, taxonomic distinctness and species composition, using both old and new analytical approaches. Results have shown how: (1 the forest type dominated by Fagus sylvatica is characterized by high complexity, with marked compositional, structural and biodiversity differences; (2 beech forests of Pigelleto di Piancastagnaio and Valle della Corte show the highest plants diversity values. The ecological characteristics of these areas, which sustain high diversity values, are unique and of great conservation interest; (3 the use of species richness as the only diversity measure have not allowed an efficient differentiation between studied areas. Indeed, the use of different indexes and analytical methods is required to detect multiple characteristics of biological diversity, as well as to carry out efficient biodiversity surveys aimed to develop optimal conservation strategies. In the future, we plan to apply the sampling methodology and the analytical approach used in this paper to characterize plants diversity of similar forest types.

  16. Techno-economic analysis of using corn stover to supply heat and power to a corn ethanol plant - Part 2: Cost of heat and power generation systems

    Energy Technology Data Exchange (ETDEWEB)

    Mani, Sudhagar [University of Georgia; Sokhansanj, Shahabaddine [ORNL; Togore, Sam [U.S. Department of Energy; Turhollow Jr, Anthony F [ORNL

    2010-03-01

    This paper presents a techno-economic analysis of corn stover fired process heating (PH) and the combined heat and power (CHP) generation systems for a typical corn ethanol plant (ethanol production capacity of 170 dam3). Discounted cash flow method was used to estimate both the capital and operating costs of each system and compared with the existing natural gas fired heating system. Environmental impact assessment of using corn stover, coal and natural gas in the heat and/or power generation systems was also evaluated. Coal fired process heating (PH) system had the lowest annual operating cost due to the low fuel cost, but had the highest environmental and human toxicity impacts. The proposed combined heat and power (CHP) generation system required about 137 Gg of corn stover to generate 9.5 MW of electricity and 52.3 MW of process heat with an overall CHP efficiency of 83.3%. Stover fired CHP system would generate an annual savings of 3.6 M$ with an payback period of 6 y. Economics of the coal fired CHP system was very attractive compared to the stover fired CHP system due to lower fuel cost. But the greenhouse gas emissions per Mg of fuel for the coal fired CHP system was 32 times higher than that of stover fired CHP system. Corn stover fired heat and power generation system for a corn ethanol plant can improve the net energy balance and add environmental benefits to the corn to ethanol biorefinery.

  17. Techno-economic analysis of using corn stover to supply heat and power to a corn ethanol plant - Part 2: Cost of heat and power generation systems

    Energy Technology Data Exchange (ETDEWEB)

    Mani, S. [Biological and Agricultural Engineering, Driftmier Engineering Center, University of Georgia, Athens, GA 30602 (United States); Sokhansanj, S.; Turhollow, A.F. [Environmental Sciences Division, Oak Ridge National Laboratory, P. O. Box 2008, Oak Ridge, TN 37831 (United States); Tagore, S. [Office of Biomass Program, U.S. Department of Energy, Washington, DC 20585 (United States)

    2010-03-15

    This paper presents a techno-economic analysis of corn stover fired process heating (PH) and the combined heat and power (CHP) generation systems for a typical corn ethanol plant (ethanol production capacity of 170 dam{sup 3}). Discounted cash flow method was used to estimate both the capital and operating costs of each system and compared with the existing natural gas fired heating system. Environmental impact assessment of using corn stover, coal and natural gas in the heat and/or power generation systems was also evaluated. Coal fired process heating (PH) system had the lowest annual operating cost due to the low fuel cost, but had the highest environmental and human toxicity impacts. The proposed combined heat and power (CHP) generation system required about 137 Gg of corn stover to generate 9.5 MW of electricity and 52.3 MW of process heat with an overall CHP efficiency of 83.3%. Stover fired CHP system would generate an annual savings of 3.6 M$ with an payback period of 6 y. Economics of the coal fired CHP system was very attractive compared to the stover fired CHP system due to lower fuel cost. But the greenhouse gas emissions per Mg of fuel for the coal fired CHP system was 32 times higher than that of stover fired CHP system. Corn stover fired heat and power generation system for a corn ethanol plant can improve the net energy balance and add environmental benefits to the corn to ethanol biorefinery. (author)

  18. MODULAR AUTOMATED COMPLEX OF THE SOLAR WATER HEATING PLANT FOR AGRICULTURAL OBJECTS

    Directory of Open Access Journals (Sweden)

    Gazalov V. S.

    2015-11-01

    Full Text Available The article deals with the system, providing automatic control of the solar water heating system with the abilities to store in internal memory and to transmit by the cellular network the information about the conditions of the plant and the occurring failure conditions. The common principles of the building the automatic system with the modular principles are shown. The article solves the issue about the quality of the water supply through the quality parameters which provided by the considered system. The methods of the active and passive loss minimizing of the heat of the water in the tank are shown. The usage of the active loss minimizing system was considered. The block-scheme of the implementation of the automatic system with described abilities are shown. The compulsory and auxiliary blocks of the automatic system are shown. The algorithm of the checking of the water supply quality parameters was presented. The study considers methods of the storing of the parameters of the working conditions of the plant and the occurring failure modes as well as the remote information of the attending personnel by the cellular networks. The advantages of the conducting of the system log are shown. The preliminary calculation of the memory capacity for storing the system log was completed. The advantages of the described automatic system with relation to the constructing, controlling, service and research of the described solar water heating systems are shown

  19. Feasibility Assessment of Using Power Plant Waste Heat in Large Scale Horticulture Facility Energy Supply Systems

    Directory of Open Access Journals (Sweden)

    Min Gyung Yu

    2016-02-01

    Full Text Available Recently, the Korean government has been carrying out projects to construct several large scale horticulture facilities. However, it is difficult for an energy supply to operate stably and economically with only a conventional fossil fuel boiler system. For this reason, several unused energy sources have become attractive and it was found that power plant waste heat has the greatest potential for application in this scenario. In this study, we performed a feasibility assessment of power plant waste heat as an energy source for horticulture facilities. As a result, it was confirmed that there was a sufficient amount of energy potential for the use of waste heat to supply energy to the assumed area. In Dangjin, an horticultural area of 500 ha could be constructed by utilizing 20% of the energy reserves. In Hadong, a horticulture facility can be set up to be 260 ha with 7.4% of the energy reserves. In Youngdong, an assumed area of 65 ha could be built utilizing about 19% of the energy reserves. Furthermore, the payback period was calculated in order to evaluate the economic feasibility compared with a conventional system. The initial investment costs can be recovered by the approximately 83% reduction in the annual operating costs.

  20. Habitat Range of two Alpine Medicinal Plants in a Trans-Himalayan Dry Valley, Central Nepal

    Institute of Scientific and Technical Information of China (English)

    Bharat Babu SHRESTHA; Pramod Kumar JHA

    2009-01-01

    Understanding of the habitat range of threatened Himalayan medicinal plants which are declining in their abundance due to high anthropogenic disturbances is essential for developing conservation strategies and agro-technologies for cultivation. In this communication, we have discussed the habitat range of two alpine medicinal plants, Aconitum naviculare (Briihl) Stapf and Neopierorhiza scrophulariiflora (Pennel) Hong in a trans-Himalayan dry valley of central Nepal, Manang district. They are the most prioritized medicinal plants of the study area in terms of ethnomedicinal uses. A. naviculare occurs on warm and dry south facing slopes between 4090-4650 m asl along with sclerophyllous and thorny alpine scrubs, while N. serophulariiflora is exclusively found on cool and moist north facing slope between 4o0o and 4400 m asl where adequate water is available from snow melt to create a suitable habitat for this wetland dependent species. The soil in rooting zone of the two plants differs significantly in organic carbon (OC), organic matter (OM), total nitrogen (N) and carbon to nitrogen (C/N) ratio. Due to cool and moist condition of N. scrophulariiflora habitat, accumulation of soil OC is higher, but soil N content is lower probably due to slow release from litter, higher leaching loss and greater retention in perennial live biomass of the plant. The C/N ratio of soil is more suitable in A. navuculare habitat than that of N scrophulariiflora for N supply. Warm and sunny site with N rich soft can be suitable for cultivation of A. naviculare, while moist and cool site with organic soil for N. scrophulariiflora. The populations of both the plants are fragmented and small. Due to collection by human and trampling damage by livestock, the population of A. naviculare was found absent in open areas in five of the six sampling sites and it was confined only within the bushes of alpine scrubs. For N. serophulariiflora, high probability of complete receding of small glaciers may

  1. Heat Shock Proteins: A Review of the Molecular Chaperones for Plant Immunity

    Directory of Open Access Journals (Sweden)

    Chang-Jin Park

    2015-12-01

    Full Text Available As sessile organisms, plants are exposed to persistently changing stresses and have to be able to interpret and respond to them. The stresses, drought, salinity, chemicals, cold and hot temperatures, and various pathogen attacks have interconnected effects on plants, resulting in the disruption of protein homeostasis. Maintenance of proteins in their functional native conformations and preventing aggregation of non-native proteins are important for cell survival under stress. Heat shock proteins (HSPs functioning as molecular chaperones are the key components responsible for protein folding, assembly, translocation, and degradation under stress conditions and in many normal cellular processes. Plants respond to pathogen invasion using two different innate immune responses mediated by pattern recognition receptors (PRRs or resistance (R proteins. HSPs play an indispensable role as molecular chaperones in the quality control of plasma membrane-resident PRRs and intracellular R proteins against potential invaders. Here, we specifically discuss the functional involvement of cytosolic and endoplasmic reticulum (ER HSPs/chaperones in plant immunity to obtain an integrated understanding of the immune responses in plant cells.

  2. Preliminary design of the Carrisa Plains solar central receiver power plant. Volume III, Book 3. Appendices. Part 2

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S. K.

    1983-12-31

    The auxiliary heat transport systems of the Carrisa Plains Solar Power Plant (CPSPP) comprise facilities which are used to support plant operation and provide plant safety and maintenance. The facilities are the sodium purification system, argon cover gas system, sodium receiving and filling system, sodium-water reaction product receiving system, and safety and maintenance equipment. The functions of the facilities of the auxiliary system are described. Design requirements are established based on plant operating parameters. Descriptions are given on the system which will be adequate to perform the function and satisfy the requirements. Valve and equipment lists are included in the appendix.

  3. The market potential for solar heating plants in some European countries

    Energy Technology Data Exchange (ETDEWEB)

    Zinko, H; Bjaerklev, J.; Margen, P. [ZW Energiteknik AB, Nykoeping (Sweden)

    1996-03-01

    This study evaluates the market potential for solar collectors for residential heating in six European countries: Sweden, Denmark, Germany, Netherlands, Italy and Greece. The study is based on statistical information about the population, buildings, energy consumption and climatic conditions in the respective regions. The market potential was determined for systems supplying hot water and space heating in small houses and multi family houses, as well as for central block heating and district heating systems. Only systems with diurnal storage were taken into account. The technical potential was derived by analyzing the available roof areas, making allowance construction obstacles, unfavourable orientation, shadowing etc. Furthermore, commercial considerations, such as cost of competing energy sources, e.g. cogeneration and other low cost sources were considered. In accordance with our expectations, we assumed that the solar costs will decrease by 30 to 50% and that the market will increase by 30%/year during the next ten years, due to growing energy prices and by public financial support in an initial phase. It was found that there exists a commercial solar energy market in Greece for small systems and that the market could be nearly commercial in Italy. In the other countries the market must be stimulated by subsidies in order to take off. The total net potential for solar collectors in the six countries was found to about 100 Mm{sup 2} for small systems, and 60 Mm{sup 2} for large systems, corresponding to about 70 TWh/year. In a rough estimate we can say that the net solar collector market potential is about 1 m{sup 2}/inhabitant in north and central Europe, and 0.5m{sup 2} in south Europe. Although systems for seasonal storage were not included in our analysis, it is probable that these systems will increase the net market potential by a factor of 2-3. 9 refs

  4. Optimization of heating systems. Up on the way to a series-produced individual heating plant; Optimierung von Heizungssystemen. Auf dem Weg zur serienmaessig individuellen Heizungsanlage

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, R. [Bosch Thermotechnik GmbH, Wetzlar (Germany). Produktmanagement Buderus Deutschland

    2008-07-01

    Normal utilization grades of almost 110% referring to the lower heating value H-1 characterize modern thermal energy generators. However, the average yearly utilization rate of medium and larger heating plants only range at barely 70% according to a current analysis. An overall concept can provide remedy. The solution present in this contribution consists of modules that can be combined. These module contain all components like pumps, actuators, armatures, feeler and insulation. (orig.)

  5. Optimum power yield for bio fuel fired combined heat and power plants

    Energy Technology Data Exchange (ETDEWEB)

    Broden, Henrik; Nystroem, Olle; Joensson, Mikael

    2012-05-15

    Plant owners, suppliers, research institutions, industry representatives and (supporting) authorities are continuing to question the viability of what can be expected by increasing the steam data and the efficiency of cogeneration plants. In recent years, the overall conditions for investment in CHP have changed. Today, there is access to new materials that allow for more advanced steam data while maintaining availability. Although the financial environment with rising prices of electricity, heating and fuel along with the introduction of energy certificates and the interest in broadening the base of fuel has changed the situation. At the same time as the increased interest in renewable energy production creates competition among energy enterprises to find suppliers, increased prices for materials and labor costs have also resulted in increased investment and maintenance costs. Research on advanced steam data for biomass-fired power cogeneration plants has mainly emphasized on technical aspects of material selection and corrosion mechanisms based on performance at 100 % load looking at single years. Reporting has rarely been dealing with the overall economic perspective based on profitability of the CHP installations throughout their entire depreciation period. In the present report studies have been performed on how the choice of steam data affects the performance and economy in biomass-fired cogeneration plants with boilers of drum type and capacities at 30, 80 and 160 MWth with varied steam data and different feed water system configurations. Profitability is assessed on the basis of internal rate of return (IRR) throughout the amortization period of the plants. In addition, sensitivity analyses based on the most essential parameters have been carried out. The target group for the project is plant owners, contractors, research institutions, industry representatives, (supporting) authorities and others who are faced with concerns regarding the viability of what

  6. Fuel-oil cogeneration plant for textile Industry. Central de cogeneracion a fueloleo para industria textil

    Energy Technology Data Exchange (ETDEWEB)

    Navarro Larrauri, M.; Diez Hernandez, J.; Villasante Diaz, A. (IDOM, Ingenieria y Consultoria, S.A. (Spain))

    1993-10-01

    Aznar S.A. is a textile factory especially sensitive to electricity distribution failures. They produce the subsequent shut down at the manufacturing process and several hours of maintenance tasks. A cogeneration plant has been installed to provide electricity and thermal energy to the process. Since the location is far from Natural Gas pipelines the system includes fuel-oil as energy source. Annual electricity production will be 23.300 MWh and 6.400 MWh of them will be exported into the grid. Fuel-oil consumption at the heat exchanger is reduced by 47%, but the whole factory consumption increases a 247% due to the high consumption of the engine. This increase is compensated by revenues from selling electricity and electricity savings. These facts, together with maintenance cost saving leads to a pay back time of 3.3. years. (Author)

  7. Exergy analysis of thermoelectric power plants; Analisis exergetico de centrales termicas

    Energy Technology Data Exchange (ETDEWEB)

    Chejne J, Farid; Florez E, Whady F.; Ordonez R, Juan C.; Botero, G.; Edgar, A. [Universidad Pontificia Bolivariana, Medellin (Colombia). Grupo de Energia y Termodinamica

    1997-12-31

    An analysis of an electric energy generation plant based on first and second law of thermodynamics has been done. In this paper, a detailed approach to the concepts of quantity and quality of energy is presented. Usually, when energy is in an organized form (high quality energy like work), it does not degrade the environment, therefore, the associated cost to improve it is null. In contrast, the conversion process of unorganized energy (i.e. low quality such as heat), has an implicit impact on the surroundings. The analysis address the need for studying industrial processes having into account the availability or exergy in order to understand systems which degrade or destroy the quality of an energy resource. (author) 8 refs., 3 figs., 1 tab.; e-mail: fchejne at janua.upb.edu.co

  8. Investigation of thermal energy transport from an anisotropic central heating element to the adjacent channels: A multipoint flux approximation

    KAUST Repository

    Salama, Amgad

    2015-02-01

    The problem of heat transfer from a central heating element pressed between two clad plates to cooling channels adjacent and outboard of the plates is investigated numerically. The aim of this work is to highlight the role of thermal conductivity anisotropy of the heating element and/or the encompassing plates on thermal energy transport to the fluid passing through the two channels. When the medium is anisotropic with respect to thermal conductivity; energy transport to the neighboring channels is no longer symmetric. This asymmetry in energy fluxes influence heat transfer to the coolant resulting in different patterns of temperature fields. In particular, it is found that the temperature fields are skewed towards the principal direction of anisotropy. In addition, the heat flux distributions along the edges of the heating element are also different as a manifestation of thermal conductivity anisotropy. Furthermore, the peak temperature at the channel walls change location and magnitude depending on the principal direction of anisotropy. Based on scaling arguments, it is found that, the ratio of width to the height of the heating system is a key parameter which can suggest when one may ignore the effect of the cross-diagonal terms of the full conductivity tensor. To account for anisotropy in thermal conductivity, the method of multipoint flux approximation (MPFA) is employed. Using this technique, it is possible to find a finite difference stencil which can handle full thermal conductivity tensor and in the same time enjoys the simplicity of finite difference approximation. Although the finite difference stencil based on MPFA is quite complex, in this work we apply the recently introduced experimenting field approach which construct the global problem automatically.

  9. Effects of N on Plant Response to Heat-wave: A Field Study with Prairie Vegetation

    Institute of Scientific and Technical Information of China (English)

    Dan Wang; Scott A. Heckathorn; Kumar Mainali; E. William Hamilton

    2008-01-01

    More intense, more frequent, and longer heat-waves are expected in the future due to global warming, which could have dramatic ecological impacts. Increasing nitrogen (N) availability and its dynamics will likely impact plant responses to heat stress and carbon (C) sequestration in terrestrial ecosystems. This field study examined the effects of N availability on plant response to heat-stress (HS) treatment in naturally-occurring vegetation. HS (5 d at ambient or 40.5 ℃) and N treatments (±N) were applied to 16 1 m2 plots in restored prairie vegetation dominated by Andropogon gerardii (warm-season C4 grass) and Solidago canadensis (warm-season C3 forb). Before, during, and after HS, air, canopy, and soil temperature were monitored; net CO2 assimilation (Pn), quantum yield of photosystem Ⅱ (φPsⅡ), stomatal conductance (gs), and leaf water potential (Ψw) of the dominant species and soil respiration (Rsolf) of each plot were measured daily during HS. One week after HS, plots were harvested, and C% and N% were determined for rhizosphere and bulk soil, and above-ground tissue (green/senescent leaf, stem, and flower). Photosynthetic N-use efficiency (PNUE) and N resorption rate (NRR) were calculated. HS decreased Pn, gs, Ψw, and PNUE for both species, and +N treatment generally increased these variables (±HS), but often slowed their poat-HS recovery. Aboveground biomass tended to decrease with HS in both species (and for green leaf mass in S. canadensis), but decrease with +N for ,4. gerardii and increase with +N for S. canadensis. For A. gerardii, HS tended to decrease N% in green tissues with +N, whereas in S. canadensis, HS increased N% in green leaves.Added N decreased NRR for A. gerardii and HS increased NRR for S. canadensis. These results suggest that heat waves,though transient, could have significant effects on plants, communities, and ecosystem N cycling, and N can influence the effect of heat waves.

  10. Advances in processing technologies for titanium heat exchanger tubes of fossil and nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Likhareva, T.P.; Tchizhik, A.A.; Chavchanidze, N.N. [Polzanov Central Boiler and Turbine Institute, St. Petersburg (Russian Federation)

    1998-12-31

    The advances in processing technologies for titanium heat exchangers with rolled and welded tubes of fossil and nuclear power plants in Russia are presented. The special methodology of investigations with constant small strain rate have been used to study the effects of mixed corrosion and creep processes in condensers cooled by sea or synthetic sea waters. The results of corrosion creep tests and K1scc calculations are given. The Russian science activities concerning condensers manufactured from titanium show the possibilities for designing structures with very high level service reliability in different corrosion aggressive mediums with high total salt, Cl-ion and oxygen contents. (orig.)

  11. CORRELATION ANALYSIS OF SURFACE TEMPERATURE OF ROOFTOPS, STREETSCAPES AND URBAN HEAT ISLAND EFFECT: CASE STUDY OF CENTRAL SYDNEY

    Directory of Open Access Journals (Sweden)

    Ehsan Sharifi

    2015-01-01

    Full Text Available Cities are frequently experiencing artificial heat stress, known as the Urban Heat Island (UHI effect. The UHI effect is commonly present in cities due to increased urbanization, where anthropogenic heat and human modifications have altered the characteristics of surfaces and atmosphere. Urban structure, land cover and metabolism are underlined as UHI key contributors and can result in higher urban densities being up to 10°C hotter compared to their peri-urban surroundings. The UHI effect increases the health-risk of spending time outdoors and boosts the need for energy consumption, particularly for air-conditioning during summer. Under investigation is what urban features are more resilient to the surface layer Urban Heat Island (sUHI effect in precinct scale. In the context of Sydney, this ongoing research aims to explore the most heat resilient urban features at precinct scale. This UHI investigation covers five highdensity precincts in central Sydney and is based on a nocturnal remote-sensing thermal image of central Sydney taken on 6 February 2009. Comparing the surface temperature of streetscapes and buildings’ rooftops (dominant urban horizontal surfaces, indicates that open spaces and particularly streetscapes are the most sensitive urban elements to the sUHI effect. The correlations between street network intensity, open space ratio, urban greenery ratio and the sUHI effect is being analysed in Sydney’s high-density precincts. Results indicate that higher open space ratio and street network intensity correlate significantly to higher sUHI effect at precinct scale. Meanwhile, 10% increase in the urban greenery can effectively decrease the precinct temperature by 0.6°C.

  12. Screening of the topical anti-inflammatory activity of some Central American plants.

    Science.gov (United States)

    Sosa, S; Balick, M J; Arvigo, R; Esposito, R G; Pizza, C; Altinier, G; Tubaro, Aurelia

    2002-07-01

    Hexane, chloroform and methanol extracts of seven herbal drugs used in the folk medicine of Central America against skin disorders (Aristolochia trilobata leaves and bark, Bursera simaruba bark, Hamelia patens leaves, Piper amalago leaves, and Syngonium podophyllum leaves and bark) were evaluated for their topical anti-inflammatory activity against the Croton oil-induced ear oedema in mice. Most of the extracts induced a dose-dependent oedema reduction. The chloroform extract of almost all the drugs exhibited interesting activities with ID(50) values ranging between 108 and 498 micro g/cm(2), comparable to that of indomethacin (93 micro g/cm(2)). Therefore, the tested plants are promising sources of principles with high anti-inflammatory activity.

  13. The economic and environmental impacts of biofuel taxes on heating plants in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Braennlund, R.; Kristroem, B.; Sisask, A.

    1998-12-31

    Sweden`s energy policy is currently based on a large-scale introduction of biofuels. Following a 1980 nuclear power referendum, the current plan is to phase out nuclear power, replacing nuclear energy with renewable energy sources. This policy is supported by various tax breaks for biofuels. There is an ongoing discussion about a restructuring of the energy tax system, which will have far-reaching impact on the markets for biofuels. This paper evaluates the impact of changes in current energy taxation by analyzing a panel of approximately 150 district heating plants in Sweden. We estimate plant-specific production functions and derive the economic repercussions of the tax. We also estimate the resulting changes of emissions of sulfur, NOX and particulates and assess the externality costs Arbetsrapport 258. 6 refs, 4 figs, 11 tabs

  14. Amaranthus cruentus L. is suitable for cultivation in Central Italy: field evaluation and response to plant densities

    Directory of Open Access Journals (Sweden)

    Paolo Casini

    2014-12-01

    Full Text Available The aim of this study was to determine the possibility of amaranth cultivation in Central Italy and to determine the optimum plant density. Field trials were carried out in 2011 and 2012 under non-irrigated conditions in Tuscany (43° 18’ N, 11° 47’ E. Twelve accessions of two amaranth species (Amaranthus cruentus L. and A. hypochondriacus L. were utilised. Genotypes were evaluated over a two-year period using a RCB design with three replicates. The effects of plant density were investigated in 2012. A with a split-plot design was used, where the A. cruentus accessions (AMES 5148, PI 511719 and PI 643045 constituted the main plots. Plant densities (7.5, 15, 30 and 60 plants m–2 constituted the subplots. Plants were transplanted at the 3-4 true leaf stage. Morphological traits were determined using 5 plants selected from the two central rows of the sampling area. Plots were hand-harvested and cleaned with a mechanical grid with appropriate sieve diameters. A. cruentus was shown to be more suitable to the Central Italy agro-ecological conditions than A. hypochondriacus. The accessions derived from Mexico (PI 477913, PI 576481, PI 643045, PI 643053, and PI 6495079, Guatemala (PI 511719 and Puerto Rico (AMES 5148, had both higher grain yields and a greater stability over the two-year period, with a mean grain production ranging from 2.8 to 3.2 t ha–1. The severe climatic stress in 2012 (high temperatures and aridity, resulted in a 43-60% reduction in seed production compared to that of the previous year. Under these conditions, PI 511719, AMES 26015, AMES 5386, AMES 5148, PI 477913 yielded on average 1.9 t ha–1. Yields of A. hypochondriacus were negligible in both years, probably attributable to greater photoperiod sensitivity, resulting in reduced flowering and delayed maturity. By increasing density up to 60 and 30 plants m–2 for PI 511719 and AMES 5148, respectively, grain production was increased by 55%. As the plant population

  15. Thermodynamic cycles of nuclear power plants; Les cycles thermodynamiques des centrales nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Normand, T.; Andreani, J.; Tejedor, V.

    2010-07-01

    Above all a nuclear power plant is a thermal system whose efficiency relies on the thermodynamic cycle that turns the heat produced by the fission of uranium nuclei into electricity. The thermodynamic yield is an essential parameter to dimension a power plant. This book is dedicated to the presentation of the thermodynamic cycles that have been chosen in the different types of French PWR: CP0, P4, N4 and EPR. These cycles are classical steam cycles that have been used and optimized for 40 years, but they are physically limited and do not respond to the expectations of future generations of reactors. The last part deals with the thermodynamic cycles that might be involved in the fourth generation of nuclear reactors: cycles with super-critical steam, direct cycles for high temperature gas, indirect gas cycles, and cycles with super-critical CO{sub 2}. The first part of the book gives an account of the situation of nuclear power in France. (A.C.)

  16. Comparative analysis of surface urban heat island effect in Central Sydney

    OpenAIRE

    E Sharifi; Lehmann, Steffen

    2014-01-01

    The Urban Heat Island (UHI) effect can result in higher urban densities being significantly hotter (frequently more than 4 °C, even up to 10 °C) compared to their peri-urban surroundings. Such artificial heat stress increases the health risk of spending time outdoors and boosts the need for energy consumption, particularly for cooling during summer. Urban structure, land cover and metabolism are underlined as key contributors in city scale. Under question is which urban configurations can mak...

  17. Solar space and water heating system at Stanford University Central Food Services Building. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-05-01

    This active hydronic domestic hot water and space heating system was 840 ft/sup 2/ of single-glazed, liquid, flat plate collectors and 1550 gal heat storage tanks. The following are discussed: energy conservation, design philosophy, operation, acceptance testing, performance data, collector selection, bidding, costs, economics, problems, and recommendations. An operation and maintenance manual and as-built drawings are included in appendices. (MHR)

  18. Heat flow and its coalbed gas effects in the central-south area of the Huaibei coalfield, eastern China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Based on an analysis of the present geo-temperature field and the thermal conductivity (K) of 62 samples from the central-south area of the Huaibei coalfield in eastern China, we calculated the heat flow and plotted its distribution map. The results show that the average heat flow in the research area is about 60 mW/m2. It is different from other major energy basins in the North China Plate, but has close relationship with the regional geology and the deep geological setting. The heat flow is comparatively higher in the southeastern, central, and northwestern areas than in the northeastern and southwestern areas. The geo-temperature distribution map of the bottom interface of the Permian coal measure was drawn by calculating its embedding depth and geo-temperature gradients. Finally, the present gas generation condition of the Permian coal measure is discussed by associating with the temperature condition, the vitrinite reflectance (Ro), the metamorphism of coal and tectonic-burial evolution. The study indicates all present characters of the Permian coal measure, such as lower present temperature, higher Ro value, middle-high rank coals, and uplift and extension events after the coal measure sediment, are favorable for the generation of secondary biogenic gas, but not thermogenic gas or primary biogenic gas.

  19. Reconnaissance heat flow and Geothermal gradient study in north central Owyhee county, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Blackwell, D.D.

    1975-09-01

    Temperature data were obtained in 41 wells, thermal conductivity in 12 wells, and published data were synthesized in order to investigate the geothermal character of an area in northern Owyhee County, Idaho. This area includes the Bruneau and Grand View-Castle Creek KGRA's and is characterized by a large number of warm water artesian irrigation wells. In the Oreana-Grand View areas the geothermal gradient to 3000 feet is 4.0 {+-} 1 F/100 ft and the heat flow is about 2.1 {+-} .2 HFU (about normal for the western US). The southern part of the Oreana area along the upper part of Castle Creek and the Little Valley-Bruneau areas have geothermal gradients ranging from 5 to 8 F/100 ft and heat flow values from 50% to 100% above the regional average. Part of the Murphy area has a geothermal gradient of about 4.0 F/100 ft and normal heat flow while the other part has gradients of 6 to 10 F/100 ft and above-regional heat flow. The high values may be directly or indirectly (via geothermal systems) associated with shallow magmatic heat sources, or with regional ground water flow. If local magmatic heat sources are present they may occur along the southern hingeline of the Snake River Plains. Suggests for further work are included.

  20. Thermal analysis of the heat recuperator of a combined cycle thermoelectric central; Analisis termico del recuperador de calor de una central termoelectrica de ciclo combinado

    Energy Technology Data Exchange (ETDEWEB)

    Romero Paredes, Hernando; Sanchez, I.; Lazcano, L. C.; Ambriz, Juan Jose; Alvarez, M. [Universidad Autonoma Metropolitana-Iztapalapa, Mexico, D. F. (Mexico); Gonzalez, O. [Comision Federal de Electricidad, Tula (Mexico)

    1996-12-31

    The thermoelectric centrals of the combined cycle type (Brayton Cycle and Rankine Cycle) present a series of opportunities to increase the efficiency of the combined cycle or of the generated power. This paper shows the methodology for the performance of energy balances in a heat recuperator (H. R.), typically employed in the combined cycle stations operating in Mexico, for the assessment of the energy harnessing in the different sections conforming a H. R. The effect of the installation of evaporative coolers and/or an absorption cooling system at the gas turbine compressor intake on the steam generation in the heat recuperator, is evaluated. This extra generation of steam is quantified for its potential use in the same absorption refrigeration system. From the assessment, it follows up that the steam generation in the H.R. is inversely proportional to the ambient temperature and that, although the increased amount of steam generated can not be harnessed in total by the steam turbine, the remaining fraction is good enough to cover the heat demand for the operation of the refrigeration system. [Espanol] Las centrales termoelectricas del tipo ciclo combinado (ciclo Brayton y ciclo Rankine) presentan un conjunto de oportunidades para incrementar la eficiencia del ciclo combinado o bien la potencia generada. En el presente trabajo se expone la metodologia para realizar los balances de energia en un recuperador de calor (R.C.) tipicamente utilizado en las Centrales de Ciclo Combinado (CCC) que operan en Mexico, para evaluar el aprovechamiento de la energia en las diferentes secciones que conforman un R.C. Se evalua el efecto que tiene la instalacion de enfriadores evaporativos y/o un sistema de enfriamiento por absorcion en la succion del compresor de la turbina de gas sobre la generacion de vapor en el recuperador de calor. Se cuantifica esta generacion extra de vapor para su posible utilizacion en el mismo sistema de refrigeracion por absorcion. De la evaluacion se

  1. Heat flow diagrams with and without a deaerator for steam turbine plants with T-250/300-23.5 turbines

    Science.gov (United States)

    Valamin, A. E.; Kultyshev, A. Yu.; Shibaev, T. L.; Gol'dberg, A. A.; Stepanov, M. Yu.

    2016-11-01

    A T-250/300-240 turbine (currently known as T-250/300-23.5), which is operated at 31 steam turbine plants, is the largest in the world extraction turbine (by the heating extraction load) and one of the largest by the nominal capacity. All steam turbine plants equipped with T-250/300-23.5 turbines of different modifications are operated in large cities of Russia and the neighboring countries covering a significant part of the needs of cities for the electric power and almost fully supplying them with heat power. The design life of a significant part of the operated steam turbine plants of this family is either expired or almost expired. It refers to both the turbine unit (including a turbine and a generator) and the turbine plant equipment. For steam turbine plants equipped with T-250/300-23.5 turbines, which were initially designed and mounted for work with deaerators at electric power stations, the heat flow diagrams with and without a deaerator were compared. The main advantages and disadvantages of each scheme were shown. It was concluded that, for the newly constructed power units with supercritical steam parameters, it is preferable to use the heat flow diagram without a deaerator; for the upgraded blocks, if there are no objective reasons for the removal of a deaerator, it is recommended to keep the existing heat flow diagram of a turbine plant.

  2. Effect of volume loading on the Frank-Starling relation during reductions in central blood volume in heat-stressed humans

    DEFF Research Database (Denmark)

    Bundgaard-Nielsen, Morten; Wilson, T E; Seifert, Thomas;

    2010-01-01

    from whom pulmonary capillary wedge pressure (PCWP), central venous pressure and SV (via thermodilution) were obtained while central blood volume was reduced via lower-body negative pressure (LBNP) during normothermia, whole-body heating (increase in blood temperature 1 degrees C), and during whole......During reductions in central blood volume while heat stressed, a greater decrease in stroke volume (SV) for a similar decrease in ventricular filling pressure, compared to normothermia, suggests that the heart is operating on a steeper portion of a Frank-Starling curve. If so, volume loading...... of heat-stressed individuals would shift the operating point to a flatter portion of the heat stress Frank-Starling curve thereby attenuating the reduction in SV during subsequent decreases in central blood volume. To investigate this hypothesis, right heart catheterization was performed in eight males...

  3. 2010 Annual Wastewater Reuse Report for the Idaho National Laboratory Site's Central Facilities Area Sewage Treatment Plant

    Energy Technology Data Exchange (ETDEWEB)

    Mike lewis

    2011-02-01

    This report describes conditions, as required by the state of Idaho Wastewater Reuse Permit (#LA-000141-03), for the wastewater land application site at Idaho National Laboratory Site’s Central Facilities Area Sewage Treatment Plant from November 1, 2009, through October 31, 2010. The report contains the following information: • Site description • Facility and system description • Permit required monitoring data and loading rates • Status of special compliance conditions • Discussion of the facility’s environmental impacts. During the 2010 permit year, approximately 2.2 million gallons of treated wastewater was land-applied to the irrigation area at Central Facilities Area Sewage Treatment plant.

  4. 2012 Annual Wastewater Reuse Report for the Idaho National Laboratory Site's Central facilities Area Sewage Treatment Plant

    Energy Technology Data Exchange (ETDEWEB)

    Mike Lewis

    2013-02-01

    This report describes conditions, as required by the state of Idaho Wastewater Reuse Permit (#LA-000141-03), for the wastewater land application site at Idaho National Laboratory Site’s Central Facilities Area Sewage Treatment Plant from November 1, 2011, through October 31, 2012. The report contains the following information: • Site description • Facility and system description • Permit required monitoring data and loading rates • Status of compliance conditions and activities • Discussion of the facility’s environmental impacts. During the 2012 permit year, no wastewater was land-applied to the irrigation area of the Central Facilities Area Sewage Treatment Plant.

  5. Transgenic tobacco plants overexpressing a grass PpEXP1 gene exhibit enhanced tolerance to heat stress.

    Directory of Open Access Journals (Sweden)

    Qian Xu

    Full Text Available Heat stress is a detrimental abiotic stress limiting the growth of many plant species and is associated with various cellular and physiological damages. Expansins are a family of proteins which are known to play roles in regulating cell wall elongation and expansion, as well as other growth and developmental processes. The in vitro roles of expansins regulating plant heat tolerance are not well understood. The objectives of this study were to isolate and clone an expansin gene in a perennial grass species (Poa pratensis and to determine whether over-expression of expansin may improve plant heat tolerance. Tobacco (Nicotiana tabacum was used as the model plant for gene transformation and an expansin gene PpEXP1 from Poa pratensis was cloned. Sequence analysis showed PpEXP1 belonged to α-expansins and was closely related to two expansin genes in other perennial grass species (Festuca pratensis and Agrostis stolonifera as well as Triticum aestivum, Oryza sativa, and Brachypodium distachyon. Transgenic tobacco plants over-expressing PpEXP1 were generated through Agrobacterium-mediated transformation. Under heat stress (42°C in growth chambers, transgenic tobacco plants over-expressing the PpEXP1 gene exhibited a less structural damage to cells, lower electrolyte leakage, lower levels of membrane lipid peroxidation, and lower content of hydrogen peroxide, as well as higher chlorophyll content, net photosynthetic rate, relative water content, activity of antioxidant enzyme, and seed germination rates, compared to the wild-type plants. These results demonstrated the positive roles of PpEXP1 in enhancing plant tolerance to heat stress and the possibility of using expansins for genetic modification of cool-season perennial grasses in the development of heat-tolerant germplasm and cultivars.

  6. Naturalization of central European plants in North America: species traits, habitats, propagule pressure, residence time.

    Science.gov (United States)

    Pyšek, Petr; Manceur, Ameur M; Alba, Christina; McGregor, Kirsty F; Pergl, Jan; Stajerová, Katerina; Chytrý, Milan; Danihelka, Jiří; Kartesz, John; Klimesova, Jitka; Lucanova, Magdalena; Moravcová, Lenka; Nishino, Misako; Sadlo, Jiri; Suda, Jan; Tichy, Lubomir; Kühn, Ingolf

    2015-03-01

    The factors that promote invasive behavior in introduced plant species occur across many scales of biological and ecological organization. Factors that act at relatively small scales, for example, the evolution of biological traits associated with invasiveness, scale up to shape species distributions among different climates and habitats, as well as other characteristics linked to invasion, such as attractiveness for cultivation (and by extension propagule pressure). To identify drivers of invasion it is therefore necessary to disentangle the contribution of multiple factors that are interdependent. To this end, we formulated a conceptual model describing the process of invasion of central European species into North America based on a sequence of "drivers." We then used confirmatory path analysis to test whether the conceptual model is supported by a statistical model inferred from a comprehensive database containing 466 species. The path analysis revealed that naturalization of central European plants in North America, in terms of the number of North American regions invaded, most strongly depends on residence time in the invaded range and the number of habitats occupied by species in their native range. In addition to the confirmatory path analysis, we identified the effects of various biological traits on several important drivers of the conceptualized invasion process. The data supported a model that included indirect effects of biological traits on invasion via their effect on the number of native range habitats occupied and cultivation in the native range. For example, persistent seed banks and longer flowering periods are positively correlated with number of native habitats, while a stress-tolerant life strategy is negatively correlated with native range cultivation. However, the importance of the biological traits is nearly an order of magnitude less than that of the larger scale drivers and highly dependent on the invasion stage (traits were associated

  7. Carbon dioxide enrichment alleviates heat stress by improving cellular redox homeostasis through an ABA-independent process in tomato plants.

    Science.gov (United States)

    Li, X; Ahammed, G J; Zhang, Y Q; Zhang, G Q; Sun, Z H; Zhou, J; Zhou, Y H; Xia, X J; Yu, J Q; Shi, K

    2015-01-01

    Plant responses to elevated CO₂ and high temperature are critically regulated through a complex network of phytohormones and redox homeostasis. However, the involvement of abscisic acid (ABA) in plant adaptation to heat stress under elevated CO₂ conditions has not been thoroughly studied. This study investigated the interactive effects of elevated CO₂ (800 μmol·mol(-1) ) and heat stress (42 °C for 24 h) on the endogenous level of ABA and the cellular redox state of two genotypes of tomato with different ABA biosynthesis capacities. Heat stress significantly decreased maximum photochemical efficiency of PSII (Fv/Fm) and leaf water potential, but also increased levels of malondialdehyde (MDA) and electrolyte leakage (EL) in both genotypes. Heat-induced damage was more severe in the ABA-deficient mutant notabilis (not) than in its parental cultivar Ailsa Craig (Ailsa), suggesting that a certain level of endogenous ABA is required to minimise the heat-induced oxidative damage to the photosynthetic apparatus. Irrespective of genotype, the enrichment of CO₂ remarkably stimulated Fv/Fm, MDA and EL in heat-stressed plants towards enhanced tolerance. In addition, elevated CO₂ significantly strengthened the antioxidant capacity of heat-stressed tomato seedlings towards a reduced cellular redox state for a prolonged period, thereby mitigating oxidative stress. However, elevated CO₂ and heat stress did not alter the endogenous level of ABA or the expression of its biosynthetic gene NCED2 in either genotype, indicating that ABA is not involved in elevated CO₂ -induced heat stress alleviation. The results of this study suggest that elevated CO₂ alleviated heat stress through efficient regulation of the cellular redox poise in an ABA-independent manner in tomato plants.

  8. Small heat-shock proteins and leaf cooling capacity account for the unusual heat tolerance of the central spike leaves in Agave tequilana var. Weber.

    Science.gov (United States)

    Luján, Rosario; Lledías, Fernando; Martínez, Luz María; Barreto, Rita; Cassab, Gladys I; Nieto-Sotelo, Jorge

    2009-12-01

    Agaves are perennial crassulacean acid metabolism (CAM) plants distributed in tropical and subtropical arid environments, features that are attractive for studying the heat-shock response. In agaves, the stress response can be analysed easily during leaf development, as they form a spirally shaped rosette, having the meristem surrounded by folded leaves in the centre (spike) and the unfolded and more mature leaves in the periphery. Here, we report that the spike of Agave tequilana is the most thermotolerant part of the rosette withstanding shocks of up to 55 degrees C. This finding was inconsistent with the patterns of heat-shock protein (Hsp) gene expression, as maximal accumulation of Hsp transcripts was at 44 degrees C in all sectors (spike, inner, middle and outer). However, levels of small HSP (sHSP)-CI and sHSP-CII proteins were conspicuously higher in spike leaves at all temperatures correlating with their thermotolerance. In addition, spike leaves showed a higher stomatal density and abated more efficiently their temperature several degrees below that of air. We propose that the greater capacity for leaf cooling during the day in response to heat stress, and the elevated levels of sHSPs, constitute part of a set of strategies that protect the SAM and folded leaves of A. tequilana from high temperatures.

  9. Integration of solar process heat into an existing thermal desalination plant in Qatar

    Science.gov (United States)

    Dieckmann, S.; Krishnamoorthy, G.; Aboumadi, M.; Pandian, Y.; Dersch, J.; Krüger, D.; Al-Rasheed, A. S.; Krüger, J.; Ottenburger, U.

    2016-05-01

    The water supply of many countries in the Middle East relies mainly on water desalination. In Qatar, the water network is completely fed with water from desalination plants. One of these power and desalination plants is located in Ras Abu Fontas, 20 km south of the capital Doha. The heat required for thermal desalination is provided by steam which is generated in waste heat recovery boilers (HRB) connected to gas turbines. Additionally, gas fired boilers or auxiliary firing in the HRBs are used in order to decouple the water generation from the electricity generation. In Ras Abu Fontas some auxiliary boilers run 24/7 because the HRB capacity does not match the demand of the desalination units. This paper contains the techno-economic analysis of two large-scale commercial solar field options, which could reduce the fuel consumption significantly. Both options employ parabolic trough technology with a nominal saturated steam output of 350 t/h at 15 bar (198°C, 240 MW). The first option uses direct steam generation without storage while the second relies on common thermal oil in combination with a molten salt thermal storage with 6 hours full-load capacity. The economic benefit of the integration of solar power depends mainly on the cost of the fossil alternative, and thus the price (respectively opportunity costs) of natural gas. At a natural gas price of 8 US-/MMBtu the internal rate of return on equity (IRR) is expected at about 5%.

  10. Life-cycle assessment of a Waste-to-Energy plant in central Norway: Current situation and effects of changes in waste fraction composition.

    Science.gov (United States)

    Lausselet, Carine; Cherubini, Francesco; Del Alamo Serrano, Gonzalo; Becidan, Michael; Strømman, Anders Hammer

    2016-12-01

    Waste-to-Energy (WtE) plants constitute one of the most common waste management options to deal with municipal solid waste. WtE plants have the dual objective to reduce the amount of waste sent to landfills and simultaneously to produce useful energy (heat and/or power). Energy from WtE is gaining steadily increasing importance in the energy mix of several countries. Norway is no exception, as energy recovered from waste currently represents the main energy source of the Norwegian district heating system. Life-cycle assessments (LCA) of WtE systems in a Norwegian context are quasi-nonexistent, and this study assesses the environmental performance of a WtE plant located in central Norway by combining detailed LCA methodology with primary data from plant operations. Mass transfer coefficients and leaching coefficients are used to trace emissions over the various life-cycle stages from waste logistics to final disposal of the ashes. We consider different fractions of input waste (current waste mix, insertion of 10% car fluff, 5% clinical waste and 10% and 50% wood waste), and find a total contribution to Climate Change Impact Potential ranging from 265 to 637gCO2eq/kg of waste and 25 to 61gCO2eq/MJ of heat. The key drivers of the environmental performances of the WtE system being assessed are the carbon biogenic fraction and the lower heating value of the incoming waste, the direct emissions at the WtE plant, the leaching of the heavy metals at the landfill sites and to a lesser extent the use of consumables. We benchmark the environmental performances of our WtE systems against those of fossil energy systems, and we find better performance for the majority of environmental impact categories, including Climate Change Impact Potential, although some trade-offs exist (e.g. higher impacts on Human Toxicity Potential than natural gas, but lower than coal). Also, the insertion of challenging new waste fractions is demonstrated to be an option both to cope with the excess

  11. EXPERIMENTAL RESEARCH AND DESIGN ON HEAT TRANSFER OF EVAPORATOR USED IN THE LARGE QUICK FREEZE PLANT

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The evaporator is the main part of a quick-freeze equipment. There are many factors influencing the heat transfer coefficient of an evaporator. The most important factors among them are the fin shape, tube diameter, distance of fin space, frost, and velocity of air flow etc. They mainly influence the thermal efficiency of an evaporator, and therefore its thermal efficiency has direct relationship with the whole efficiency of the quick freeze plant. Evaporators with different structural types have different heat transfer efficiency. In order to obtain high efficiency structure of evaporator, 8 evaporator models with different fin shape, tube diameter and tube arrangement are analyzed and compared. The calculation results show that the integral waved fins, equilateral-triangle arranged small diameter tubes and varying fin-spacing has the highest heat transfer coefficient. The experimental result also shows that the evaporator with this type of structure has better thermal efficiency. The experimental result is in good agreement with the calculation result. It can instruct engineering design for usual designer. A real quick-freeze equipment is designed and put into production. The result shows that, compared with traditional domestic quick-freeze equipments, this equipment decreases by 40% in size and by 20% in energy consumption.

  12. Costs of urban area retrofit to district heating and cooling systems: north-central cities

    Energy Technology Data Exchange (ETDEWEB)

    Santini, D J; Davis, A A; Marder, S M

    1978-03-01

    This study considers the major urbanized areas of six U.S. cities (Washington, D.C.; St. Louis; Cleveland; Milwaukee; Detroit; Chicago) to arrive at reasonably accurate estimates of costs required to retrofit them with district heating and cooling systems. Only costs associated with heating and hot water are addressed here. Demand estimates and energy-supply analyses are made, and component capital costs are estimated to arrive at annualized system costs. Finally, a comparison of alternative energy-delivery options is made, and estimates of scarce-fuel savings are derived. 39 refs., 12 figs., 14 tables.

  13. Relationship between Aflatoxin Contamination and Physiological Responses of Corn Plants under Drought and Heat Stress

    Directory of Open Access Journals (Sweden)

    Nacer Bellaloui

    2012-11-01

    Full Text Available Increased aflatoxin contamination in corn by the fungus Aspergillus flavus is associated with frequent periods of drought and heat stress during the reproductive stages of the plants. The objective of this study was to evaluate the relationship between aflatoxin contamination and physiological responses of corn plants under drought and heat stress. The study was conducted in Stoneville, MS, USA under irrigated and non-irrigated conditions. Five commercial hybrids, P31G70, P33F87, P32B34, P31B13 and DKC63-42 and two inbred germplasm lines, PI 639055 and PI 489361, were evaluated. The plants were inoculated with Aspergillus flavus (K-54 at mid-silk stage, and aflatoxin contamination was determined on the kernels at harvest. Several physiological measurements which are indicators of stress response were determined. The results suggested that PI 639055, PI 489361 and hybrid DKC63-42 were more sensitive to drought and high temperature stress in the non-irrigated plots and P31G70 was the most tolerant among all the genotypes. Aflatoxin contamination was the highest in DKC63-42 and PI 489361 but significantly lower in P31G70. However, PI 639055, which is an aflatoxin resistant germplasm, had the lowest aflatoxin contamination, even though it was one of the most stressed genotypes. Possible reasons for these differences are discussed. These results suggested that the physiological responses were associated with the level of aflatoxin contamination in all the genotypes, except PI 639055. These and other physiological responses related to stress may help examine differences among corn genotypes in aflatoxin contamination.

  14. Effective heat transport of Gulf Stream to subarctic North Atlantic during Miocene cooling: evidence from "Köppen signatures" of fossil plant assemblages

    Directory of Open Access Journals (Sweden)

    T. Denk

    2013-08-01

    Full Text Available Shallowing of the Panama Sill and the closure of the Central American Seaway initiated the modern Loop Current/Gulf Stream circulation pattern during the Miocene but no direct evidence has yet been provided for effective heat transport to the northern North Atlantic during that time. Climatic signals from 11 precisely-dated plant-bearing sedimentary rock formations in Iceland, spanning 15–0.8 million years (Myr, resolve the impacts of the developing Miocene global thermohaline circulation on terrestrial vegetation in the subarctic North Atlantic region. "Köppen signatures" were implemented to express climatic properties of fossil plant taxa and their potential modern analogues using the principal concept of the generic Köppen–Geiger climate system, which is based on plant distribution patterns. Using Köppen signatures and the correlation between Köppen climate zones and major global vegetation zones, fossil assemblages were used to trace major vegetation shifts. This evidence was combined with evidence from tectonics and palaeoceanography. In contrast to the global climatic trend, the vegetation record reveals no cooling between ~ 15 and 12 Myr, whereas periods of climatic deterioration between 12–10 Myr, 8–4 Myr, and in the Pleistocene are in phase with increased pulses of ice-rafted debris in the Northern Hemisphere. The observed sequence of climate change in the northern North Atlantic can only be explained by an effective Gulf Stream-mediated heat transport from the middle Miocene onwards.

  15. An ethnobotanical study of plants used for the treatment of livestock diseases in Tikamgarh District of Bundelkhand, Central India

    Institute of Scientific and Technical Information of China (English)

    Raj Kumar Verma

    2014-01-01

    Objective: To explore and document the information regarding usage of ethnoveterinary medicinal plants utilized by rural farmers and traditional herbal healers for livestock healthcare in Tikamgarh District of Bundelkhnad, Central India. Methods: The remote villages of Tikamgarh district were regularly visited from July 2011 to June 2012. Following the methods of Jain and Goel (1995) information regarding the usage of ethnoveterinary medicinal plants was collected.Results:various plant parts and their combinations for the treatment of more than 36 diseases in the studied area. Trees (17 species) were found to be the most used Ethnoveterinary medicinal plants followed by herbs (15 species), shrubs (6 species) and grasses (3) in descending order. The most common diseases cough, diarrhoea and fever were treated by 04 ethnoveterinary medicinal plant species.Conclusions:The present study recommended that the crop and medicinal plant genetic A total of 41 plant species in 39 genera and 25 families were used traditionally with resources cannot be conserved and protected without conserving/managing of the agro-ecosystem or natural habitat of medicinal plants and the socio-cultural organization of the local people. The same may be applied to protect indigenous knowledge, related to the use of medicinal and other wild plants. Introduction of medicinal plants in degraded government and common lands could be another option for promoting the rural economy together with environmental conservation, but has not received attention in the land rehabilitation programs in this region.

  16. WEATHER CONDITIONS OF MAIZE VEGETATION IN CONNECTION WITH THE PLANTING DATES IN THE ARID ZONE OF CENTRAL CISCAUCASUSIA

    Directory of Open Access Journals (Sweden)

    Kravchenko R. V.

    2016-02-01

    Full Text Available There were reviewed the results of the study of the dependence of main phenological phases of development of corn hybrids of different maturity groups of the selection of Krasnodar Research Institute of Agriculture named after P.P. Lukyanenko in the arid zone of Central Ciscaucasia (Ross 199, Ross 299, Krasnodar 382 and Krasnodar 410 and the AllRussian Research Institute of Corn (Mashuk 170, Newton, RIC 345 and Eric, as well as early-middle Rossiyskaya 1 from the changes of average daily air temperature of planting dates and preplant seed treatment by the preparation "TMTD-plus", containing the growth promoter called Krezatsin in its composition. The studies were conducted in accordance with the thematic plan of scientific researches of the department of crop and forage production of Stavropol State Agrarian University. The technology of maize growing on the experimental plot corresponds to the standard technology for this area and culture. The sowing was performed in three stages. The first (early sowing period was at t = + 7 ... +8 ° C. The second (recommended – was at t = + 10 ... + 12 ° C. The third (later sowing period was at t = +15 ° C. There was identified a high inverse correlation between the average daily air temperature and the duration of the intraphase periods of maize propagation. Thus, at the shifting of maize sowing dates with the second half of May on the second half of April we have optimization of heat regime in the generative period and rising of the efficiency of use of thermal resources of the region. There was marked the acceleration of development of corn seedlings when the average daily air temperatures was up to 12 ° C at the samples with the application of the disinfectant TMTD-plus

  17. Detection of carbon nanotubes in plant roots through microwave-induced heating

    Science.gov (United States)

    Irin, Fahmida; Shrestha, Babina; Canas, Jaclyn; Saed, Mohammad; Green, Micah

    2012-02-01

    We demonstrate a novel technique for quantitative detection of CNTs in biological samples by utilizing the thermal response of CNTs under microwave irradiation. In particular, rapid heating of CNTs due to microwave absorption was employed to quantify the amount of CNTs present in alfalfa plant roots. Alfalfa roots were prepared by injecting a known amount of CNTs (single walled and multi walled) and exposed to 30-50 W microwave power to generate calibration curves (temperature rise vs. CNT mass). These calibration curves serve as a characterization tool to determine the unknown amount of CNTs absorbed by alfalfa plant roots grown in CNT-laden soil with superior accuracy and sensitivity. Moreover, the threshold for detectable CNT concentration is much lower than common analytical methods of detecting nanomaterials, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy. Considering the lack of effective detection methods for CNT uptake in plants, this method is not only unique but also practical, as it addresses a major problem in the field of nanotoxicology risk assessment.

  18. Scale Resistant Heat Exchanger for Low Temperature Geothermal Binary Cycle Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Hays, Lance G. [Energent Corporation, Santa Ana, CA (United States)

    2014-11-18

    Phase 1 of the investigation of improvements to low temperature geothermal power systems was completed. The improvements considered were reduction of scaling in heat exchangers and a hermetic turbine generator (eliminating seals, seal system, gearbox, and lube oil system). A scaling test system with several experiments was designed and operated at Coso geothermal resource with brine having a high scaling potential. Several methods were investigated at the brine temperature of 235 ºF. One method, circulation of abradable balls through the brine passages, was found to substantially reduce scale deposits. The test heat exchanger was operated with brine outlet temperatures as low as 125 ºF, which enables increased heat input available to power conversion systems. For advanced low temperature cycles, such as the Variable Phase Cycle (VPC) or Kalina Cycle, the lower brine temperature will result in a 20-30% increase in power production from low temperature resources. A preliminary design of an abradable ball system (ABS) was done for the heat exchanger of the 1 megawatt VPC system at Coso resource. The ABS will be installed and demonstrated in Phase 2 of this project, increasing the power production above that possible with the present 175 ºF brine outlet limit. A hermetic turbine generator (TGH) was designed and manufacturing drawings produced. This unit will use the working fluid (R134a) to lubricate the bearings and cool the generator. The 200 kW turbine directly drives the generator, eliminating a gearbox and lube oil system. Elimination of external seals eliminates the potential of leakage of the refrigerant or hydrocarbon working fluids, resulting in environmental improvement. A similar design has been demonstrated by Energent in an ORC waste heat recovery system. The existing VPC power plant at Coso was modified to enable the “piggyback” demonstration of the TGH. The existing heat exchanger, pumps, and condenser will be operated to provide the required

  19. Centralized cooling mode based on cogeneration power plant and hot water pi pe network%基于热电厂与热水管网的集中供冷模式

    Institute of Scientific and Technical Information of China (English)

    滕树龙; 赵玉清; 战家乙; 孙健

    2014-01-01

    Describes a new way for summer cooling based on the central heating system of combined heat and power generation.The characteristic is that the absorption heat pump driven by steam extracted from steam turbine is set up in cogeneration power plant.The absorption heat pump is used for recovering waste heat in exhausted steam of steam turbine or circulating cooling water.Network water is heated by cascade utilization.At the user' s heating station,absorption chillers driven by hot water and solution-humidifying air handling units are set up to undertake building cooling load in summer.By this way,high temperature hot water from cogeneration power plant is used to drive refrigeration units in summer,which can improve the equipment utilization rate of the central heating system and reduce the power load of cities in summer.%介绍了一种利用热电联产集中供热系统实现夏季供冷的模式,其特点是在热电厂设置汽轮机抽汽驱动的吸收式热泵,回收汽轮机乏汽或循环冷却水余热,梯级加热热网水;在用户热力站设置热水型吸收式制冷机和溶液调湿型空气处理机,承担用户夏季空调冷负荷。该方式夏季利用热电厂的高温热水驱动制冷机,可提高集中供热系统的设备利用率,降低夏季城市的供电负荷。

  20. Population dynamics in central and edge populations of a narrowly endemic plant.

    Science.gov (United States)

    Aikens, Melissa L; Roach, Deborah A

    2014-07-01

    Species' range limits can be caused by environmental gradients, and in such cases, abundance is thought to be highest in the center of a species range and decline towards the edge (the abundant-center model). Although in theory decreased abundance is caused by a decline in performance at the edge, it has been shown that performance and abundance are not necessarily related. Few studies have compared abundance and performance in center and edge populations of endemic species, whose ranges may be restricted by the availability of specialized habitat rather than environmental gradients across their range. Additionally, range-wide studies that examine both northern and southern edge populations are rare. We used Roan Mountain rattlesnake-root (Prenanthes roanensis), a perennial plant endemic to the Southern Appalachians (USA), to compare abundance and performance between central populations and populations at the northern and southern edges of the range. To account for multiple fitness components across the life cycle, we measured performance of edge populations as vital-rate contributions to population growth rate compared to the center. Abundance did not decline at the range edge, but some vital-rate contributions were lower in edge populations compared to central populations. However, each edge population differed in which vital-rate contributions were lower compared to the center. Our results do not support the abundant-center model, and it appears that local factors are important in structuring the range of this endemic species. It is important to recognize that when implementing conservation or management plans, populations in close proximity may have substantial variation in demographic rates due to differences in the local environment.

  1. 2015 Annual Wastewater Reuse Report for the Idaho National Laboratory Site’s Central Facilities Area Sewage Treatment Plant

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Michael George [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-02-01

    This report describes conditions, as required by the state of Idaho Wastewater Reuse Permit (#LA-000141-03), for the wastewater land application site at the Idaho National Laboratory Site’s Central Facilities Area Sewage Treatment Plant from November 1, 2014, through October 31, 2015.

  2. A New Method to Determine Central Wavelength and Optimal Bandwidth for Predicting Plant Nitrogen Uptake in Winter Wheat

    Institute of Scientific and Technical Information of China (English)

    YAO Xin-feng; YAO Xia; TIAN Yong-chao; NI Jun; LIU Xiao-jun; CAO Wei-xing; ZHU Yan

    2013-01-01

    Plant nitrogen (N) uptake is a good indicator of cropNstatus. In this study, a new method was designed to determine the central wavelength, optimal bandwidth and vegetation indices for predicting plantNuptake (gNm-2) in winter wheat (Triticum aestivum L.). The data were collected from the ground-based hyperspectral reflectance measurements in eight field experiments on winter wheat of different years, eco-sites, varieties,Nrates, sowing dates, and densities. The plantNuptake index (PNUI) based on NDVI of 807 nm combined with 736 nm was selected as the optimal vegetation index, and a linear model was developed with R2 of 0.870 and RMSE of 1.546 gNm-2 for calibration, and R2 of 0.834, RMSE of 1.316 gNm-2, slope of 0.934, and intercept of 0.001 for validation. Then, the effect of the bandwidth of central wavelengths on model performance was determined based on the interaction between central wavelength and bandwidth expansion. The results indicated that the optimal bandwidth varies with the changes of the central wavelength and with the interaction between the two bands in one vegetation index. These findings are important for prediction and diagnosis of plantNuptake more precise and accurate in crop management.

  3. Comparative analysis of the performance of string and central inverter topology at a large PV utility plant with varying topography

    DEFF Research Database (Denmark)

    Paasch, Kasper; Nymand, Morten; Kjær, Søren Bækhøj

    2015-01-01

    MPPT) and a series of small central inverters (60 kW, 1 MPPT) in the same PV plant under varying irradiation conditions and also including the potential detrimental effect of the horizontally tilt of the solar panels due to area topography variation. It has been shown that the gain from using multiple...

  4. Comparative analysis of cooling systems for energy equipment of combined heat and power plants and nuclear power plants

    Science.gov (United States)

    Reutov, B. F.; Lazarev, M. V.; Ermakova, S. V.; Zisman, S. L.; Kaplanovich, L. S.; Svetushkov, V. V.

    2016-07-01

    In the 20th century, the thermal power engineering in this country was oriented toward oncethrough cooling systems. More than 50% of the CHPP and NPP capacities with once-through cooling systems put into operation before the 1990s were large-scale water consumers but with minimum irretrievable water consumption. In 1995, the Water Code of the Russian Federation was adopted in which restrictions on application of once-through cooling systems for newly designed combined heat and power plants (CHPPs) were introduced for the first time. A ban on application of once-through systems was imposed by the current Water Code of the Russian Federation (Federal law no. 74-FZ, Art. 60 Cl. 4) not only for new CHPPs but also for those to be modified. Clause 4 of Article 60 of the Water Code of the Russian Federation contravenes law no. 7-FZ "On Protection of the Environment" that has priority significance, since the water environment is only part of the natural environment and those articles of the Water Code of the Russian Federation that are related directly to electric power engineering, viz., Articles 46 and 62. In recent decades, the search for means to increase revenue charges and the economic pressure on the thermal power industry caused introduction by law of charges for use of water by cooling systems irrespective of the latter's impact on the water quality of the source, the environment, the economic efficiency of the power production, and the living conditions of the people. The long-range annual increase in the water use charges forces the power generating companies to switch transfer once-through service water supply installations to recirculating water supply systems and once-through-recirculating systems with multiple reuse of warm water, which drastically reduces the technical, economic, and ecological characteristic of the power plant operation and also results in increasing power rates for the population. This work comprehensively substantiates the demands of

  5. Energy-effective method for low-temperature deaeration of make-up water on the heating supply system of heat power plants

    Science.gov (United States)

    Sharapov, V. I.; Pazushkina, O. V.; Kudryavtseva, E. V.

    2016-01-01

    The technology for low-temperature deaeration of make-up water of heating supply systems is developed that makes it possible to substantially enhance the energy efficiency of heat power plants (HPPs). As a desorbing agent for deaeration of make-up water of heating supply systems, it is proposed to use not steam or superheated water but a gas supplied to boiler burners. Natural gas supplied to steam boilers of HPPs has very low or often negative temperature after reducing devices. At the same time, it is virtually corrosive gas-free (oxygen and carbon dioxide) and, therefore, can be successfully used as the desorbing agent for water deaeration. These factors make it possible to perform deaeration of make-up water of heating supply systems at relatively low temperatures (10-30°C). Mixing of the cold deaerated make-up water with the return delivery water results in a significant decrease in the temperature the return delivery water before a lower delivery heater of a dual-purpose turbine plant, increase in the power output with the heat consumption, and, consequently, enhancement in the operation efficiency of the HPP. The article presents the calculation of the consumption of gas theoretically required for deaeration and reveals the evaluation of the energy efficiency of the technology for a typical energy unit of thermal power station. The mass transfer efficiency of the deaeration of the make-up water of heating supply systems is estimated for the case of using natural gas as the desorbing agent for which the specific gas consumption required theoretically for deaeration is calculated. It is shown that the consumption of natural gas used as fuel in boilers of HPPs is sufficient for the deaeration of any volumes of the make-up water of heating supply systems. The energy efficiency of the developed technology is evaluated for a typical heat power-generating unit of the HPP with a T-100-12.8 turbine. The calculation showed that the application of the new technology

  6. An Overview of Atmospheric Fluidized Bed Combustion Systems as Applied to Army Scale Central Heat Plants

    Science.gov (United States)

    1992-11-01

    turbulence, offers several advantages: less volatilization of alkali components, reduced chance for hot spots on boiler and shell surfaces, less...properties. Pretreating limestone-based sulfur sorbents to open the pores for sulfur dioxide diffusion can be done by precalcination. Treating the sorbents...Carpet waste Coal washing waste Biomass waste Sulfur-laden waste gases Vegetable compost Paint sludge "• Lower power requirements for fuel

  7. Central Heat and Power Plant Coal Dust and Silica Risk Management, Eielson Air Force Base, Alaska

    Science.gov (United States)

    2014-12-11

    autoimmune diseases and in death from other nonmalignant respiratory diseases , including chronic obstructive pulmonary disease . There are some... Occupational Safety and Health Administration Occupational Exposure to Respirable Crystalline Silica; Proposed Rule. This consultative letter is in...strategies, occupational and environmental exposure limits, and air sampling methods as they apply to CHPP operations. 15. SUBJECT TERMS Silica

  8. Accumulation and Soil-to-Plant Transfer Factor of Lead and Manganese in some Plant Species in Semnan Province, Central Iran

    Directory of Open Access Journals (Sweden)

    Mohamad Sakizadeh

    2016-04-01

    Full Text Available Background: Heavy metals have detrimental effects on the health of human being. The values of manganese (Mn and lead (Pb in some plant species and soil samples in an arid area of Iran were evaluated in this study. Methods: The values of Pb and Mn in 94 plant samples from 8 plant species and the related soil samples in 2010 were considered in Shahroud and Damghan, central Iran. Moreover, the soil-to-plant transfer factors of these two elements were investigated. Results: Except for barley, the values of Pb in all of the considered plants were higher than the standard level of 0.3 mg/kg. The amounts of Mn in all of the plant species other than pistachio were higher than the standard level of 25 mg/kg. As a whole, the bio-concentration factor of Mn was higher than that of Pb in the study area. Conclusion: None of the soil-to-plant transfer factors exceeded one. Grape recorded the highest amounts of Pb and Mn compared with that of other investigated plant species. However, since its respective bio concentration factor (BCF was lower than one, it cannot be considered as a hyper accumulator of lead and manganese.

  9. The combined effect of salinity and heat reveals a specific physiological, biochemical and molecular response in tomato plants.

    Science.gov (United States)

    Rivero, Rosa M; Mestre, Teresa C; Mittler, Ron; Rubio, Francisco; Garcia-Sanchez, Francisco; Martinez, Vicente

    2014-05-01

    Many studies have described the response mechanisms of plants to salinity and heat applied individually; however, under field conditions some abiotic stresses often occur simultaneously. Recent studies revealed that the response of plants to a combination of two different stresses is specific and cannot be deduced from the stresses applied individually. Here, we report on the response of tomato plants to a combination of heat and salt stress. Interestingly, and in contrast to the expected negative effect of the stress combination on plant growth, our results show that the combination of heat and salinity provides a significant level of protection to tomato plants from the effects of salinity. We observed a specific response of plants to the stress combination that included accumulation of glycine betaine and trehalose. The accumulation of these compounds under the stress combination was linked to the maintenance of a high K(+) concentration and thus a lower Na(+) /K(+) ratio, with a better performance of the cell water status and photosynthesis as compared with salinity alone. Our findings unravel new and unexpected aspects of the response of plants to stress combination and provide a proposed list of enzymatic targets for improving crop tolerance to the abiotic field environment.

  10. Optimisation of a Kalina cycle for a central receiver solar thermal power plant with direct steam generation

    DEFF Research Database (Denmark)

    Modi, Anish; Haglind, Fredrik

    2014-01-01

    Central receiver solar thermal power plants are regarded as one of the promising ways to generate electricity in near future. They offer the possibility of using high temperatures and pressures to achieve high efficiencies with standard power cycles. A direct steam generation approach can be used...... for a central receiver solar thermal power plant with direct steam generation. The variation in the cycle performance with respect to the turbine inlet ammonia mass fraction and pressure and a comparison of the initial investment with that of the basic Rankine cycle are also presented. Only high live steam...... for such plants for improved performance. This approach can also be combined with using advanced power cycles like the Kalina cycle, which uses a zeotropic mixture of ammonia and water instead of pure water as the working fluid. This paper presents the optimisation of a particular Kalina cycle layout...

  11. Palaeoclimate reconstruction within the upper Eocene in central Germany using fossil plants

    Science.gov (United States)

    Moraweck, Karolin; Kunzmann, Lutz; Uhl, Dieter; Kleber, Arno

    2013-04-01

    The Eocene has been commonly called "The world`s last greenhouse period" covering the Paleocene-Eocene Thermal Maximum (PETM) as well as the Eocene-Oligocene turnover. In the mid-latitudes of Europe this turnover was characterized by pronounced climatic changes from subtropical towards temperate conditions that were accompanied by significant vegetational changes on land. Fossil plants are regarded as excellent palaeoenvironmental proxies, because leaf physiognomy often reflects climate conditions. The study site, the Paleogene Weißelster basin in central Germany, including fluvial, estuarine and lacustrine deposits, provides several excellently preserved megafloras for reconstructions of terrestrial palaeoclimate. For our case study we used material from different stratigraphic horizons within the late Eocene Zeitz megafloral assemblage recovered from the open-cast mines of Profen and Schleenhain. These horizons cover a time interval of ca. 3 Ma. The Zeitz megafloral assemblage ("Florenkomplex") was characterized by mainly evergreen, notophyllous vegetation, consisting of warm-temperate to subtropical elements. Tropical species are present but very rare. To infer the regional climatic conditions and putative climate changes from these fossil plants we compare proxy data obtained by the application of standard methods for quantitative reconstruction of palaeoclimate data: the coexistence approach (CA), leaf margin analysis (LMA) and Climate Leaf Analysis Multivariate Program (CLAMP).Before the CA was applied to the material the list of putative nearest living relative species (NLR) was carefully revisited and partly revised. In case of the LMA approach information of so-called "silent taxa" (fossil species preserved by diaspores, leaf margin state is inferred from NLR data) were partly included in the data set. The four floras from the Zeitz megafloral assemblage show slightly different floral compositions caused by various taphonomic processes. An aim of the

  12. Optimal Design of Cogeneration Systems in Industrial Plants Combined with District Heating/Cooling and Underground Thermal Energy Storage

    Directory of Open Access Journals (Sweden)

    Vincenzo Dovì

    2011-12-01

    Full Text Available Combined heat and power (CHP systems in both power stations and large plants are becoming one of the most important tools for reducing energy requirements and consequently the overall carbon footprint of fundamental industrial activities. While power stations employ topping cycles where the heat rejected from the cycle is supplied to domestic and industrial consumers, the plants that produce surplus heat can utilise bottoming cycles to generate electrical power. Traditionally the waste heat available at high temperatures was used to generate electrical power, whereas energy at lower temperatures was either released to the environment or used for commercial or domestic heating. However the introduction of new engines, such as the ones using the organic Rankine cycle, capable of employing condensing temperatures very close to the ambient temperature, has made the generation of electrical power at low temperatures also convenient. On the other hand, district heating is becoming more and more significant since it has been extended to include cooling in the warm months and underground storage of thermal energy to cope with variable demand. These developments imply that electric power generation and district heating/cooling may become alternative and not complementary solutions for waste energy of industrial plants. Therefore the overall energy management requires the introduction of an optimisation algorithm to select the best strategy. In this paper we propose an algorithm for the minimisation of a suitable cost function, for any given variable heat demand from commercial and domestic users, with respect to all independent variables, i.e., temperatures and flowrates of warm fluid streams leaving the plants and volume and nature of underground storage. The results of the preliminary process integration analysis based on pinch technology are used in this algorithm to provide bounds on the values of temperatures.

  13. Surface Heat Budget and Solar Radiation Allocation at a Melt Pond During Summer in the Central Arctic Ocean

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shugang; ZHAO Jinping; SHI Jiuxin; JIAO Yutian

    2014-01-01

    The heat budget of a melt pond surface and the solar radiation allocation at the melt pond are studied using the 2010 Chinese National Arctic Research Expedition data collected in the central Arctic. Temperature at a melt pond surface is proportional to the air temperature above it. However, the linear relationship between the two varies, depending on whether the air temperature is higher or lower than 0℃. The melt pond surface temperature is strongly influenced by the air temperature when the latter is lower than 0℃. Both net longwave radiation and turbulent heat flux can cause energy loss in a melt pond, but the loss by the latter is larger than that by the former. The turbulent heat flux is more than twice the net longwave radiation when the air temperature is lower than 0℃. More than 50%of the radiation energy entering the pond surface is absorbed by pond water. Very thin ice sheet on the pond surface (black ice) appears when the air temperature is lower than 0℃; on the other hand, only a small percentage (5.5%) of net longwave in the solar radiation is absorbed by such a thin ice sheet.

  14. Next Generation Nuclear Plant Steam Generator and Intermediate Heat Exchanger Materials Research and Development Plan

    Energy Technology Data Exchange (ETDEWEB)

    J. K. Wright

    2010-09-01

    DOE has selected the High Temperature Gas-cooled Reactor (HTGR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production. It will have an outlet gas temperature in the range of 900°C and a plant design service life of 60 years. The reactor design will be a graphite moderated, helium-cooled, prismatic or pebble-bed reactor and use low-enriched uranium, Tri-Isotopic (TRISO)-coated fuel. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during accidents. The NGNP Materials Research and Development (R&D) Program is responsible for performing R&D on likely NGNP materials in support of the NGNP design, licensing, and construction activities. Today’s high-temperature alloys and associated ASME Codes for reactor applications are approved up to 760°C. However, some primary system components, such as the Intermediate Heat Exchanger (IHX) for the NGNP will require use of materials that can withstand higher temperatures. The thermal, environmental, and service life conditions of the NGNP will make selection and qualification of some high-temperature materials a significant challenge. Examples include materials for the core barrel and core internals, such as the control rod sleeves. The requirements of the materials for the IHX are among the most demanding. Selection of the technology and design configuration for the NGNP must consider both the cost and risk profiles to ensure that the demonstration plant establishes a sound foundation for future commercial deployments. The NGNP challenge is to achieve a significant advancement in nuclear technology while at the same time setting the stage for an economically viable deployment of the new technology in the commercial sector soon after 2020. A number of solid solution strengthened nickel based alloys have been considered for

  15. Next Generation Nuclear Plant Intermediate Heat Exchanger Materials Research and Development Plan (PLN-2804)

    Energy Technology Data Exchange (ETDEWEB)

    J. K. Wright

    2008-04-01

    DOE has selected the High Temperature Gas-cooled Reactor (HTGR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production. It will have an outlet gas temperature in the range of 900°C and a plant design service life of 60 years. The reactor design will be a graphite moderated, helium-cooled, prismatic or pebble-bed reactor and use low-enriched uranium, Tri-Isotopic (TRISO)-coated fuel. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during accidents. The NGNP Materials Research and Development (R&D) Program is responsible for performing R&D on likely NGNP materials in support of the NGNP design, licensing, and construction activities. Today’s high-temperature alloys and associated ASME Codes for reactor applications are approved up to 760°C. However, some primary system components, such as the Intermediate Heat Exchanger (IHX) for the NGNP will require use of materials that can withstand higher temperatures. The thermal, environmental, and service life conditions of the NGNP will make selection and qualification of some high-temperature materials a significant challenge. Examples include materials for the core barrel and core internals, such as the control rod sleeves. The requirements of the materials for the IHX are among the most demanding. Selection of the technology and design configuration for the NGNP must consider both the cost and risk profiles to ensure that the demonstration plant establishes a sound foundation for future commercial deployments. The NGNP challenge is to achieve a significant advancement in nuclear technology while at the same time setting the stage for an economically viable deployment of the new technology in the commercial sector soon after 2020. A number of solid solution strengthened nickel based alloys have been considered for

  16. Chemical and biological investigations of a toxic plant from Central Africa, Magnistipula butayei subsp. montana.

    Science.gov (United States)

    Karangwa, C; Esters, V; Frédérich, M; Tits, M; Kadima, J N; Damas, J; Noirfalise, A; Angenot, L

    2006-02-20

    Magnistipula butayei subsp. montana (Chrysobalanaceae) is known, in the Great Lakes Region, to possess toxicological properties. In this paper, we investigated the acute toxicity (dose levels 50-1600 mg/kg) of its aqueous extract, administered orally to adult Wistar rats. This study demonstrated that the freeze-dried aqueous extract (5%, w/w) possesses high toxicity. The extract caused hypothermia, neurological disorders, including extensor reflex of maximal convulsive induced-seizures at about 2 h after the administered dose, and death occurred (LD50=370 mg/kg) in a dose dependent manner. Blood parameter evaluation revealed slight variations, but these might not have clinical relevance. Histological examination of internal organs (lungs, liver, heart and kidneys) did not reveal any abnormality in the treated group compared to the control. Therefore, it can be concluded that Magnistipula butayei subsp. montana aqueous extract, given orally, is toxic and that its target is the central nervous system. General phytochemical screening revealed that the plant did not contain significant amounts of products known to be toxic, such as alkaloids or cardioactive glycosides, but only catechic tannins, amino acids, saponins and other aphrogen principles in the three parts of the species (fruit, leave and bark).

  17. Integral power evaluation in fossil fuel power plants; Evaluacion energetica integral en unidades de centrales termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Figueroa I, Luis R; Sanchez H, Laura E; Rodriguez M, Jose H [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Nebradt G, Jesus [Unidad de Investigacion y Desarrollo de la Subdireccion de Generacion de la Comision Federal de Electricidad, (Mexico)

    2006-07-01

    In this occasion, a methodology is presented that carries out an integral energy evaluation of fossil fuel power plants units (FFPPU) with the purpose of determining the root of the significant decrements of power produced soon after the annual maintenance service. This proposal, besides identifying the origin of the energy efficiency problems, offers information about the contributions of each one of the involved equipment in the total decrement of the unit. With this methodology, the maintenance focuses in the equipment that contributes to the greater energy loss. This document presents such methodology along with its application in a real case, results and necessary remedial actions, demonstrating that its application offers bases for the investment in corrective measures. [Spanish] En esta ocasion se presenta una metodologia que efectua una evaluacion energetica integral de las unidades de centrales termoelectricas (UCT) con el fin de determinar la raiz de los decrementos de potencia significativos producidos luego del servicio anual de mantenimiento. Dicha propuesta, ademas de identificar el origen de los problemas de eficiencia energetica, brinda informacion acerca de las aportaciones de cada uno de los equipos involucrados al decremento total de la unidad. Con esta metodologia, el mantenimiento se enfoca a los equipos que contribuyen a la mayor perdida de potencia. Este documento exhibe tal metodologia junto con su aplicacion en un caso real, resultados y las acciones correctivas necesarias, demostrando que su aplicacion ofrece bases para una inversion futura en medidas correctivas.

  18. On the use of Rotary Gas/gas Heat Exchangers as a Novel Integration Option for Heat and Water Management in Exhaust Gas Recycling Gas Turbine Plants

    OpenAIRE

    Herraiz, Laura; Hogg, Dougal; Cooper, Jim; Gibbins, Jon; Lucquiaud, Mathieu

    2014-01-01

    This work is a first-of-a-kind feasibility study investigating technology options with gas/gas rotary heat exchangers for the water management in the integration of Natural Gas Combined Cycle (NGCC) plants with post-combustion carbon capture, with and without exhaust gas recirculation (EGR). A range of configurations are examined for wet and dry cooling of the flue gas entering a post- combustion capture (PCC) absorption system, and regenerative heating of the CO2-depleted flue gas prior to t...

  19. Dissecting the proteome dynamics of the early heat stress response leading to plant survival or death in Arabidopsis.

    Science.gov (United States)

    Echevarría-Zomeño, Sira; Fernández-Calvino, Lourdes; Castro-Sanz, Ana B; López, Juan Antonio; Vázquez, Jesús; Castellano, M Mar

    2016-06-01

    In many plant species, an exposure to a sublethal temperature triggers an adaptative response called acclimation. This response involves an extensive molecular reprogramming that allows the plant to further survive to an otherwise lethal increase of temperature. A related response is also launched under an abrupt and lethal heat stress that, in this case, is unable to successfully promote thermotolerance and therefore ends up in plant death. Although these molecular programmes are expected to have common players, the overlapping degree and the specific regulators of each process are currently unknown. We have carried out a high-throughput comparative proteomics analysis during acclimation and during the early stages of the plant response to a severe heat stress that lead Arabidopsis seedlings either to survival or death. This analysis dissects these responses, unravels the common players and identifies the specific proteins associated with these different fates. Thermotolerance assays of mutants in genes with an uncharacterized role in heat stress demonstrate the relevance of this study to uncover both positive and negative heat regulators and pinpoint a pivotal role of JR1 and BAG6 in heat tolerance.

  20. District heating and cooling systems for communities through power plant retrofit and distribution network, City of Piqua, Ohio

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-09-18

    The goal of the Piqua, Ohio District Heating and Cooling Demonstration Project is to demonstrate the feasibility and efficiency of using cogenerated thermal energy from the City's Municipal Power Plant to provide residential, commercial and industrial space heating and cooling and satisfy other community energy needs as appropriate. Progress in four tasks within this project is reported. These tasks include: development of team work plan resource allocation; identification of thermal energy source market; analysis of energy market; and planning of power plant retrofits. (LCL)

  1. Life management plants at nuclear power plants PWR; Planes de gestion de vida en centrales nucleares PWR

    Energy Technology Data Exchange (ETDEWEB)

    Esteban, G.

    2014-10-01

    Since in 2009 the CSN published the Safety Instruction IS-22 (1) which established the regulatory framework the Spanish nuclear power plants must meet in regard to Life Management, most of Spanish nuclear plants began a process of convergence of their Life Management Plants to practice 10 CFR 54 (2), which is the current standard of Spanish nuclear industry for Ageing Management, either during the design lifetime of the plant, as well as for Long-Term Operation. This article describe how Life Management Plans are being implemented in Spanish PWR NPP. (Author)

  2. Impact of different national biomass policies on investment costs of biomass district heating plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-04-01

    The BIO-COST project - co-ordinated by E.V.A. - was funded by the European Commission's THERMIE Type B Programme. The objective of BIO-COST was to analyse the impact of national biomass policies on the investment costs of biomass district heating (DH) plants. The European comparison should help identifying measures to reduce investment costs for biomass DH plants and/or components down to a 'best practice' level. The investigation is based on the comparison of 20 biomass DH plants by country, with Denmark and Sweden having mainly high energy taxes as driver, while Austria and France rely mainly on subsidy systems. The results of BIO-COST show, that governmental policies can have a big impact especially on grid and buildings costs, effecting of course the overall costs of the plant enormously. Emission standards have their effects especially on the costs for technical equipment, however, this fact was not reflected in the BIO-COST data. The results do not show a clear advantage of either the energy tax approach or the subsidy approach: The French subsidy approach leads to fairly low cost levels compared to the Danish tax approach, while the Swedish tax approach seems to yield the lowest cost level. On the other hand the Austrian subsidy approach seems to intercrease investment costs. In principle both the tax as the subsidy approach can lead to the same effect: a project is calculated in such a way, that it just meets economic breakeven. This is typically the case when the project is not carried out by a private enterprise but by an operator aiming at enhanced public welfare (e.g. co-operative, municipality). In this case a subsidy model might yield more possibilities to encourage an economically efficient development, than a tax. Instead of giving subsidies as a fixed percentage of investments they could be adjusted to the actual needs of the project as proven by a standardised calculation. Of course this can create the incentive to expect higher

  3. Preliminary issues associated with the next generation nuclear plant intermediate heat exchanger design.

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.; Moisseytsev, A.; Majumdar, S.; Shankar, P. S.; Nuclear Engineering Division

    2007-04-05

    The Next Generation Nuclear Plant (NGNP), which is an advanced high temperature gas reactor (HTGR) concept with emphasis on production of both electricity and hydrogen, involves helium as the coolant and a closed-cycle gas turbine for power generation with a core outlet/gas turbine inlet temperature of 900-1000 C. In the indirect cycle system, an intermediate heat exchanger is used to transfer the heat from primary helium from the core to the secondary fluid, which can be helium, nitrogen/helium mixture, or a molten salt. The system concept for the vary high temperature reactor (VHTR) can be a reactor based on the prismatic block of the GT-MHR developed by a consortium led by General Atomics in the U.S. or based on the PBMR design developed by ESKOM of South Africa and British Nuclear Fuels of U.K. This report has made a preliminary assessment on the issues pertaining to the intermediate heat exchanger (IHX) for the NGNP. Two IHX designs namely, shell and tube and compact heat exchangers were considered in the assessment. Printed circuit heat exchanger, among various compact heat exchanger (HX) designs, was selected for the analysis. Irrespective of the design, the material considerations for the construction of the HX are essentially similar, except may be in the fabrication of the units. As a result, we have reviewed in detail the available information on material property data relevant for the construction of HX and made a preliminary assessment of several relevant factors to make a judicious selection of the material for the IHX. The assessment included four primary candidate alloys namely, Alloy 617 (UNS N06617), Alloy 230 (UNS N06230), Alloy 800H (UNS N08810), and Alloy X (UNS N06002) for the IHX. Some of the factors addressed in this report are the tensile, creep, fatigue, creep fatigue, toughness properties for the candidate alloys, thermal aging effects on the mechanical properties, American Society of Mechanical Engineers (ASME) Code compliance

  4. Analyzing the possibility of constructing the air heating system for an integrated solid fuel gasification combined-cycle power plant

    Science.gov (United States)

    Mikula, V. A.; Ryzhkov, A. F.; Val'tsev, N. V.

    2015-11-01

    Combined-cycle power plants operating on solid fuel have presently been implemented only in demonstration projects. One of possible ways for improving such plants consists in making a shift to hybrid process circuits of integrated gasification combined-cycle plants with external firing of solid fuel. A high-temperature air heater serving to heat compressed air is a key element of the hybrid process circuit. The article describes application of a high-temperature recuperative metal air heater in the process circuit of an integrated gasification combined-cycle power plant (IGCC). The available experience with high-temperature air heating is considered, and possible air heater layout arrangements are analyzed along with domestically produced heat-resistant grades of steel suitable for manufacturing such air heater. An alternative (with respect to the traditional one) design is proposed, according to which solid fuel is fired in a noncooled furnace extension, followed by mixing the combustion products with recirculation gases, after which the mixture is fed to a convective air heater. The use of this design makes it possible to achieve considerably smaller capital outlays and operating costs. The data obtained from thermal and aerodynamic calculations of the high-temperature air heater with a thermal capacity of 258 MW for heating air to a temperature of up to 800°C for being used in the hybrid process circuit of a combined-cycle power plant are presented.

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

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-09-15

    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.

  6. COGENERATION OPPORTUNITIES TO IMPROVE THE EFFICIENCY OF MICRO HEAT POWER PLANTS BASED ON AIR COOLED INTERNAL COMBUSTION ENGINES

    Directory of Open Access Journals (Sweden)

    P. A. Shchinnikov

    2017-01-01

    Full Text Available The possibilities of operation of electric generators based on internal combustion engines with air cooling under conditions of cogeneration, when, along with the electricity, heat release in different embodiments is provided. Such facilities are usually realized on the basis of gasoline internal combustion engines (i.e. gasoline is used as a fuel. They can be used in the household, by professional builders, geologists, the military and rescuers in the area of emergencies and in areas with a lack of infrastructure. The basis of the facility is the gasoline generator Hitachi-2400 with an air-cooled power of 2.4 kW. The basic methodology for the study of microthermal power plants based on an air-cooled internal combustion engine which is based on balance equations is presented. The facility operation ensures the measurement of all temperatures and expenses of operating environments for determining heat flow in accordance with the proposed methodology. The specifications of heat exchangers for utilizing the heat of exhaust flue gases are presented. The energy diagram illustrating the useful effect of the application of various heat exchangers are plotted. Cogeneration possibilities of the facility are provided, firstly, by the release of heat with the air that cools a cylinder of the internal combustion engine, and, secondly, by the release of heat of hot water heated by utilizing the heat of the leaving flue gases, and, thirdly, in the calculated version, by the release of heat with air that is sequentially heated due to the cooling of the cylinder head and then by utilizing the heat of exhaust gases. It is demonstrated that the fuel heat utilization factor can be increased from 0.22 to 0.50–0.60, depending on the adopted technical solutions.

  7. Resolution of the direct containment heating issue for all Westinghouse plants with large dry containments or subatmospheric containments

    Energy Technology Data Exchange (ETDEWEB)

    Pilch, M.M.; Allen, M.D.; Klamerus, E.W. [Sandia National Labs., Albuquerque, NM (United States)

    1996-03-01

    This report uses the methodology and scenarios described in NUREG/CR-6075 and NUREG/CR-6075, Supplement 1, to address the direct containment heating (DCH) issue for all Westinghouse plants with large dry or subatmospheric containments. DCH is considered resolved if the conditional containment failure probability (CCFP) is less than 0.1. The methodology calls for an initial screening phase in which the CCFP for each plant is calculated based on loads versus strength evaluations using plant-specific information. The DCH issue is considered resolved for a plant if the CCFP calculated in the screening phase is less than 0.01. This value is more stringent than the overall success criterion of 0.1. The CCFPs for all of the Westinghouse plants with dry containments were less than 0.01 in the screening phase calculations, and thus, the DCH issue is resolved for these plants based on containment loads alone. No additional analyses are required.

  8. Monitored performance of residential geothermal heat pumps in central Texas and Southern Michigan

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, W.N.

    1997-11-01

    This report summarizes measured performance of residential geothermal heat pumps (GHP`s) that were installed in family housing units at Ft. Hood, Texas and at Selfridge Air National Guard base in Michigan. These units were built as part of a joint Department of Defense/Department of Energy program to evaluate the energy savings potential of GHP`s installed at military facilities. At the Ft. Hood site, the GHP performance was compared to conventional forced air electric air conditioning and natural gas heating. At Selfridge, the homes under test were originally equipped with electric baseboard heat and no air conditioning. Installation of the GHP systems at both sites was straightforward but more problems and costs were incurred at Selfridge because of the need to install ductwork in the homes. The GHP`s at both sites produced impressive energy savings. These savings approached 40% for most of the homes tested. The low cost of energy on these bases relative to the incremental cost of the GHP conversions precludes rapid payback of the GHP`s from energy savings alone. Estimates based on simple payback (no inflation and no interest on capital) indicated payback times from 15 to 20 years at both sites. These payback times may be reduced by considering the additional savings possible due to reduced maintenance costs. Results are summarized in terms of 15 minute, hourly, monthly, and annual performance parameters. The results indicate that all the systems were working properly but several design shortcomings were identified. Recommendations are made for improvements in future installations at both sites.

  9. Urban heat island impacts on plant phenology: intra-urban variability and response to land cover

    Science.gov (United States)

    Zipper, Samuel C.; Schatz, Jason; Singh, Aditya; Kucharik, Christopher J.; Townsend, Philip A.; Loheide, Steven P., II

    2016-05-01

    Despite documented intra-urban heterogeneity in the urban heat island (UHI) effect, little is known about spatial or temporal variability in plant response to the UHI. Using an automated temperature sensor network in conjunction with Landsat-derived remotely sensed estimates of start/end of the growing season, we investigate the impacts of the UHI on plant phenology in the city of Madison WI (USA) for the 2012-2014 growing seasons. Median urban growing season length (GSL) estimated from temperature sensors is ˜5 d longer than surrounding rural areas, and UHI impacts on GSL are relatively consistent from year-to-year. Parks within urban areas experience a subdued expression of GSL lengthening resulting from interactions between the UHI and a park cool island effect. Across all growing seasons, impervious cover in the area surrounding each temperature sensor explains >50% of observed variability in phenology. Comparisons between long-term estimates of annual mean phenological timing, derived from remote sensing, and temperature-based estimates of individual growing seasons show no relationship at the individual sensor level. The magnitude of disagreement between temperature-based and remotely sensed phenology is a function of impervious and grass cover surrounding the sensor, suggesting that realized GSL is controlled by both local land cover and micrometeorological conditions.

  10. Solar-assisted central heating in Hamburg-Bramfeld; Solarunterstuetzte Nahwaermeversorgung Hamburg-Bramfeld

    Energy Technology Data Exchange (ETDEWEB)

    Ebel, M. [HGC Hamburg Gas Consult, Hamburg (Germany)

    1998-12-31

    About 38% of the energy consumed in Germany is used for space heating. Hot water demand of old buildings accounts for approximately 10% while buildings constructed according to modern insulation standards account for 15 - 20 %. Space heating has a considerable conservation potential, which plays an important role in terms of reducing carbon dioxide pollution. More and more new technologies for conventional thermal insulation as well as for the active use of solar energy are being developed and will soon be commercially available. (orig.) [Deutsch] In der Bundesrepublik Deutschland werden ca. 38% des Energieverbrauches fuer die Waermeversorgung von Gebaeuden eingesetzt. Auf den Warmwasserbedarf entfallen davon ca. 10% bei Altbauten und 15-20% bei Wohngebaeuden nach den heute gueltigen Waermeschutzbestimmungen. Damit liegt im Bereich der Waemreversorgung von Gebaeuden ein erhebliches Einsparpotential, welches innerhalb der Diskussion ueber die CO{sub 2}-Problematik eine immer groessere Bedeutung erlangt. Neben einer Verbesserung der konventionellen Waermedaemmung der Gebaeude werden zunehmend Techniken der aktiven Solarenergienutzung zur Einsatzreife entwickelt. (orig.)

  11. Effects of vertically ribbed surface roughness on the forced convective heat losses in central receiver systems

    Science.gov (United States)

    Uhlig, Ralf; Frantz, Cathy; Fritsch, Andreas

    2016-05-01

    External receiver configurations are directly exposed to ambient wind. Therefore, a precise determination of the convective losses is a key factor in the prediction and evaluation of the efficiency of the solar absorbers. Based on several studies, the forced convective losses of external receivers are modeled using correlations for a roughened cylinder in a cross-flow of air. However at high wind velocities, the thermal efficiency measured during the Solar Two experiment was considerably lower than the efficiency predicted by these correlations. A detailed review of the available literature on the convective losses of external receivers has been made. Three CFD models of different level of detail have been developed to analyze the influence of the actual shape of the receiver and tower configuration, of the receiver shape and of the absorber panels on the forced convective heat transfer coefficients. The heat transfer coefficients deduced from the correlations have been compared to the results of the CFD simulations. In a final step the influence of both modeling approaches on the thermal efficiency of an external tubular receiver has been studied in a thermal FE model of the Solar Two receiver.

  12. Heat and mass transfers in the Late variscan: evidence from gold depôsits in the French Massif Central

    Science.gov (United States)

    Cathelineau, M.; Boiron, M. C.; Fourcade, S.; Marignac, C.

    2003-04-01

    In many medium- to high-grade metamorphic terranes of the West European Variscan belt, there are few, if any, reliable mineral records of the retrograde path. The S Limousin area (W French Massif Central) is a good example: there, the lithotectonic pile (including numerous granite intrusions) was "freezed" below ca. 350°C (Ar dating of white micas) since ca. 340 Ma. Yet, there is evidence for subsequent, sometimes pervasive, fluid and heat pulses although the latter were not accompanied by widespread retrograde metamorphism (insufficient duration/amount). A major episode of heat and mass transfer corresponds to the formation of gold deposits, thought to have occurred at ca. 305 Ma. The study of fluid inclusions from these deposits and surrounding rocks demonstrates the persistence of heat and fluid production at depth, although the pattern of fluid circulation changed with time. (i) In a first, protracted stage (340-305 Ma), fluid circulation in the Limousin top-middle crust (300-350 Mpa, 11-13 km depth) was restricted to a set of structural drains (shear-zones hosting early quartz veins) and involved volatile-bearing (CO2-dominated) fluids that, from O-isotope evidence, were focused from deep reservoirs where used heat advection resulted in a long-lived ductile behaviour of the shear-zones contrasting with the brittle regime prevailing in the surrounding crust. (ii) Around 305 Ma, when the Limousin pile was in the upper crust (above ca. 5 km), a change occurred in the pattern of fluid circulation, simultaneously with the inception of post-thickening extension. Pervasive fluid flow occurred through a network of interconnected microcraks while the nature of the fluids was changing. A hot eas, at the scale of the "upper crust reservoir" diffuse deposition of arsenopyrite resulted in a huge regional As anomaly in the Limousin gneisses. The source of the hot saline fluid is speculative. By comparison with the SE French Massif Central, the existence of a large magmatic

  13. GEODATA: Information System Based on Geospatial for Early Warning Tracking and Analysis Agricultural Plant Diseases in Central Java

    Science.gov (United States)

    Prasetyo, S. Y. J.; Agus, Y. H.; Dewi, C.; Simanjuntak, B. H.; Hartomo, K. D.

    2017-03-01

    The Government of Indonesia is currently faced with the problems of food, especially rice. It needs in large numbers that have to import from neighboring countries. Actually, the Indonesian government has the ability to produce rice to meet national needs but is still faced with the problem of pest attack rice annually increasing extent. One of the factors is that geographically Indonesia located on the migration path of world rice insect pests (called BPH or Brown Planthoppers) (Nilaparvata lugens Stal.) It leads endemic status annually. One proposed strategy to be applied is to use an early warning system based on a specific region of the main pest population. The proposed information system called GEODATA. GEODATA is Geospatial Outbreak of Disease Tracking and Analysis. The system works using a library ESSA (Exponential Smoothing - Spatial Autocorrelation) developed in previous studies in Satya Wacana Christian University. GEODATA built to meet the qualifications required surveillance device by BMKG (Indonesian Agency of Meteorology, Climatology and Geophysics’ Central Java Provinces), BPTPH (Indonesian Agency of Plant Protection and Horticulture) Central Java Provinces, BKP-KP District Boyolali, Central Java, (Indonesian Agency of Food Security and Agriculture Field Supervisor, District Boyolali, Central Java Provinces) and farmer groups. GIS GEODATA meets the needs of surveillance devices that include: (1) mapping of the disease, (2) analysis of the dynamics of the disease, and (3) prediction of attacks / disease outbreaks in a particular region. GIS GEODATA is currently under implementation in the laboratory field observations of plant pest in Central Java province, Indonesia.

  14. Few Ant Species Play a Central Role Linking Different Plant Resources in a Network in Rupestrian Grasslands

    Science.gov (United States)

    Mello, Marco A. R.; Bronstein, Judith L.; Guerra, Tadeu J.; Muylaert, Renata L.; Leite, Alice C.; Neves, Frederico S.

    2016-01-01

    Ant-plant associations are an outstanding model to study the entangled ecological interactions that structure communities. However, most studies of plant-animal networks focus on only one type of resource that mediates these interactions (e.g, nectar or fruits), leading to a biased understanding of community structure. New approaches, however, have made possible to study several interaction types simultaneously through multilayer networks models. Here, we use this approach to ask whether the structural patterns described to date for ant-plant networks hold when multiple interactions with plant-derived food rewards are considered. We tested whether networks characterized by different resource types differ in specialization and resource partitioning among ants, and whether the identity of the core ant species is similar among resource types. We monitored ant interactions with extrafloral nectaries, flowers, and fruits, as well as trophobiont hemipterans feeding on plants, for one year, in seven rupestrian grassland (campo rupestre) sites in southeastern Brazil. We found a highly tangled ant-plant network in which plants offering different resource types are connected by a few central ant species. The multilayer network had low modularity and specialization, but ant specialization and niche overlap differed according to the type of resource used. Beyond detecting structural differences across networks, our study demonstrates empirically that the core of most central ant species is similar across them. We suggest that foraging strategies of ant species, such as massive recruitment, may determine specialization and resource partitioning in ant-plant interactions. As this core of ant species is involved in multiple ecosystem functions, it may drive the diversity and evolution of the entire campo rupestre community. PMID:27911919

  15. Central model predictive control of a group of domestic heat pumps, case study for a small district

    NARCIS (Netherlands)

    Leeuwen, van R.P.; Fink, J.; Smit, G.J.M.; Helfert, Markus; Krempels, Karl-Heinz; Donnellan, Brian; Klein, Cornel

    2015-01-01

    In this paper we investigate optimal control of a group of heat pumps. Each heat pump provides space heating and domestic hot water to a single household. Besides a heat pump, each house has a buffer for domestic hot water and a floor heating system for space heating. The paper describes models and

  16. Mirror Advanced Reactor Study (MARS). Final report. Volume 1-B. Commercial fusion electric plant

    Energy Technology Data Exchange (ETDEWEB)

    Donohue, M.L.; Price, M.E. (eds.)

    1984-07-01

    Volume 1-B contains the following chapters: (1) blanket and reflector; (2) central cell shield; (3) central cell structure; (4) heat transport and energy conversion; (5) tritium systems; (6) cryogenics; (7) maintenance; (8) safety; (9) radioactivity, activation, and waste disposal; (10) instrumentation and control; (11) balance of plant; (12) plant startup and operation; (13) plant availability; (14) plant construction; and (15) economic analysis.

  17. Feasibility of geothermal heat use in the San Bernardino Municipal Wastewater Treatment Plant. Final report, September 1980-June 1981

    Energy Technology Data Exchange (ETDEWEB)

    Racine, W.C.; Larson, T.C.; Stewart, C.A.; Wessel, H.B.

    1981-06-01

    The results of the feasibility study for utilizing low temperature geothermal heat in the City of San Bernardino Wastewater Treatment Plant are summarized. The study is presented in terms of preliminary engineering design, economic analysis, institutional issues, environmental impacts, resource development, and system implementation.

  18. Impact of soil heat on reassembly of bacterial communities in the rhizosphere microbiome and plant disease suppression

    NARCIS (Netherlands)

    Voort, van der M.; Kempenaar, Marcel; Driel, van Marc; Raaijmakers, Jos M.; Mendes, Rodrigo

    2016-01-01

    The rhizosphere microbiome offers a range of ecosystem services to the plant, including nutrient acquisition and tolerance to (a)biotic stress. Here, analysing the data by Mendes et al. (2011), we show that short heat disturbances (50 or 80 °C, 1 h) of a soil suppressive to the root pathogenic fu

  19. Elecnuc. Nuclear power plants in the world; Elecnuc. Les centrales nucleaires dans le monde

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    This 2003 version of Elecnuc contents information, data and charts on the nuclear power plants in the world and general information on the national perspectives concerning the electric power industry. The following topics are presented: 2002 highlights; characteristics of main reactor types and on order; map of the French nuclear power plants; the worldwide status of nuclear power plants on 2002/12/3; units distributed by countries; nuclear power plants connected to the Grid by reactor type groups; nuclear power plants under construction; capacity of the nuclear power plants on the grid; first electric generations supplied by a nuclear unit; electrical generation from nuclear plants by country at the end 2002; performance indicator of french PWR units; trends of the generation indicator worldwide from 1960 to 2002; 2002 cumulative Load Factor by owners; nuclear power plants connected to the grid by countries; status of license renewal applications in Usa; nuclear power plants under construction; Shutdown nuclear power plants; exported nuclear power plants by type; exported nuclear power plants by countries; nuclear power plants under construction or order; steam generator replacements; recycling of Plutonium in LWR; projects of MOX fuel use in reactors; electricity needs of Germany, Belgium, Spain, Finland, United Kingdom; electricity indicators of the five countries. (A.L.B.)

  20. Design and System Analysis of Quad-Generation Plant Based on Biomass Gasification Integrated with District Heating

    DEFF Research Database (Denmark)

    Rudra, Souman

    This thesis presents the development of energy system for simulation, techno-economic optimization and design of a quad-generation energy system based on biomass gasification. An efficient way of reducing CO2 emission from the environment is by increasing the use of biomass in the energy sector......, it possible to lay a foundation for future gasification based power sector to produce flexible output such as electricity, heat, chemicals or bio-fuels by improving energy system of existing DHP(district heating plant) integrating gasification technology. The present study investigate energy system....... Different biomass resources are used to generate heat and electricity, to produce gas fuel like bio-SNG (synthesis natural gas) and also to produce liquid fuels, such as ethanol, and biodiesel. Due to the fact that the trend of establishing new and modern plants for handling and processing biomass...

  1. Influence of heat consumers distribution and flashing vapours effect on steam consumption of evaporation plant of sugar factory

    Directory of Open Access Journals (Sweden)

    A. A. Gromkovskii

    2016-01-01

    Full Text Available The article considered the influence of the heat consumers distribution and the flashing vapours effect juice for multipleevaporator sugar factory on the consumption the main production flow of heat transfer agent – water vapor. The problem of rational distribution of heat transfer agent for of the corps multiple-evaporator is relevant from point of view of energy saving and energysaving heat of the sugar factory. The solution to this problem is advantageously carried out on the basis of quantitative mathematical description of the distribution of vapor on the corps of the evaporation plant. The heat consumers distribution should be based on technical and economic calculation. To solve this problem it is advisable to use a single equation that determines the dependence of the steam flow in the first unit evaporator on the amount of evaporated water and the method of heat consumers distribution for housing. Evaporators sugar factory has two functions – technology and heat, each of which is described by its equation. On the basis of the material and heat balance equations for the realization of the basic functions of the system evaporator written multipleevaporator equations. The solution of this system allows you to obtain the equation of the steam flow and the amount of evaporated water, taking into account the flashing vapours effect. Solution of the system should take into account the accepted design standards of sugar factories. As a result of solving the system of equation is obtained, which allows you to organize and optimize the heat consumers distribution of the corps evaporator. The equation can be used for any number of units evaporator. This equation allows you to assess the efficiency of the evaporation plant of a sugar factory. This is of great practical importance in the modernization of thermal schemes of sugar factories.

  2. Analysis of Heat Balance on Innovative-Simplified Nuclear Power Plant Using Multi-Stage Steam Injectors

    Science.gov (United States)

    Goto, Shoji; Ohmori, Shuichi; Mori, Michitsugu

    The total space and weight of the feedwater heaters in a nuclear power plant (NPP) can be reduced by replacing low-pressure feedwater heaters with high-efficiency steam injectors (SIs). The SI works as a direct heat exchanger between feedwater from condensers and steam extracted from turbines. It can attain pressures higher than the supplied steam pressure. The maintenance cost is lower than that of the current feedwater heater because of its simplified system without movable parts. In this paper, we explain the observed mechanisms of the SI experimentally and the analysis of the computational fluid dynamics (CFD). We then describe mainly the analysis of the heat balance and plant efficiency of the innovative-simplified NPP, which adapted to the boiling water reactor (BWR) with the high-efficiency SI. The plant efficiencies of this innovative-simplified BWR with SI are compared with those of a 1100MWe-class BWR. The SI model is adopted in the heat balance simulator as a simplified model. The results show that the plant efficiencies of the innovate-simplified BWR with SI are almost equal to those of the original BWR. They show that the plant efficiency would be slightly higher if the low-pressure steam, which is extracted from the low-pressure turbine, is used because the first-stage of the SI uses very low pressure.

  3. Power plant heating system integrating low temperature heat and absorption heat pumps%电厂低温热与吸收式热泵耦合供热系统研究

    Institute of Scientific and Technical Information of China (English)

    邱丽霞; 郝艳红

    2015-01-01

    On the basis of analysis on two kinds of waste heat utilization approaches,using the low-tempera-ture flue gas waste heat to heat the condensate water and feed water by installing heat exchangers in the tail flue duct,and improving the quality of steam turbine exhaust and circulating water to supply heat for users by adopting absorption heat pumps,a novel waste heat utilization system for thermal power plants was proposed.In this system,the flue gas after the air preheater is regarded as the heat pump's driving heat source,thus the absorption heat pump can recover the heat of condensation and heat the heating hot water. In addition,in order to meet the heating requirements in extremely cold periods,the heat exchanger is in-stalled after the economizer in the tail flue duct,in which the heating hot water from heat pump exit is heated by part of the flue gas extracted from outlet of the economizer.In this system,the low-temperature heat is recovered by the absorption heat pump,so that the exergy loss is reduced in the heat transfer process,the extraction steam from the steam turbine decreases and the output power increases.Further-more,combined with a 330 MW heat supply unit,this novel system's energy-saving effect was analyzed and the results were compared with that of the conventional flue gas waste heat utilization system (convention-al system I)and the conventional condensation heat heat pump system (conventional system2).The results show that,the annual standard coal consumption of the unit applying this novel system is 8 487.8 t less than that applying the conventional system I,and the output power is 1.3% to 2.7% higher than that ap-plying the conventional system II,which indicates the energy saving effect of this novel waste heat utiliza-tion system is remarkable.%基于常规烟气余热利用系统(常规系统1)及常规冷凝热热泵系统(常规系统2),提出了一种新型的电厂余热利用系统:将空气预热器(空预器)后的烟气作为

  4. Ground-water temperature of the Wyoming quadrangle in central Delaware : with application to ground-water-source heat pumps

    Science.gov (United States)

    Hodges, Arthur L.

    1982-01-01

    Ground-water temperature was measured during a one-year period (1980-81) in 20 wells in the Wyoming Quadrangle in central Delaware. Data from thermistors set at fixed depths in two wells were collected twice each week, and vertical temperature profiles of the remaining 18 wells were made monthly. Ground-water temperature at 8 feet below land surface in well Jc55-1 ranged from 45.0 degrees F in February to 70.1 degrees F in September. Temperature at 35 feet below land surface in the same well reached a minimum of 56.0 degrees F in August, and a maximum of 57.8 degrees F in February. Average annual temperature of ground water at 25 feet below land surface in all wells ranged from 54.6 degrees F to 57.8 degrees F. Variations of average temperature probably reflect the presence or absence of forestation in the recharge areas of the wells. Ground-water-source heat pumps supplied with water from wells 30 or more feet below land surface will operate more efficiently in both heating and cooling modes than those supplied with water from shallower depths. (USGS)

  5. Program of low emissions elimination and power recovery by the Krakow heat and power plant for the city of Krakow and its residents

    Energy Technology Data Exchange (ETDEWEB)

    Drezewski, J.; Kasprzyk, T. [Krakow Heat and Power Plant, Cracow (Poland)

    1995-12-31

    For over three years the Krakow Heat and Power Plant S.A. (ECK SA) has been implementing its strategy of adapting to operation and growth in the market economy. The accomplishment and results of these efforts are presented. The social and economic conditions prevailing during the transformation from a centrally controlled economy to a market economy have changed the realities and regulations that restricted the availability of energy carriers. The continual shortages and restrictions on supplies of gas, electricity, heat and even solids fuels (coke) that occurred in previous years have been replaced by a surplus. That is why many investment planning decisions have had to be revised. A sharp increase in energy carrier prices has required detailed analyses and viability studies to be made before final investment decisions are made. The choice of fuel and heating methods has begun to be dictated by the market and the economy, and not by rationing and administrative decisions. Clearly, a free market in energy generation and distribution has come into existence in the Krakow urban area. In general, these trends will produce a situation in which the fixed cost (depreciation, repairs, payroll) incurred by manufacturers and distributors will be apportioned among a smaller number of power units (MW), thus increasing the capacity price (fixed payment).

  6. 2011 Annual Wastewater Reuse Report for the Idaho National Laboratory Site’s Central Facilities Area Sewage Treatment Plant

    Energy Technology Data Exchange (ETDEWEB)

    Michael G. Lewis

    2012-02-01

    This report describes conditions, as required by the state of Idaho Wastewater Reuse Permit (LA-000141-03), for the wastewater land application site at Idaho National Laboratory Site's Central Facilities Area Sewage Treatment Plant from November 1, 2010, through October 31, 2011. The report contains the following information: (1) Site description; (2) Facility and system description; (3) Permit required monitoring data and loading rates; (4) Status of special compliance conditions and activities; and (5) Discussion of the facility's environmental impacts. During the 2011 permit year, approximately 1.22 million gallons of treated wastewater was land-applied to the irrigation area at Central Facilities Area Sewage Treatment plant.

  7. 2013 Annual Wastewater Reuse Report for the Idaho National Laboratory Site’s Central Facilities Area Sewage Treatment Plant

    Energy Technology Data Exchange (ETDEWEB)

    Mike Lewis

    2014-02-01

    This report describes conditions, as required by the state of Idaho Wastewater Reuse Permit (#LA-000141-03), for the wastewater land application site at the Idaho National Laboratory Site’s Central Facilities Area Sewage Treatment Plant from November 1, 2012, through October 31, 2013. The report contains, as applicable, the following information: • Site description • Facility and system description • Permit required monitoring data and loading rates • Status of compliance conditions and activities • Discussion of the facility’s environmental impacts. During the 2013 permit year, no wastewater was land-applied to the irrigation area of the Central Facilities Area Sewage Treatment Plant and therefore, no effluent flow volumes or samples were collected from wastewater sampling point WW-014102. However, soil samples were collected in October from soil monitoring unit SU-014101.

  8. Containment fan cooler heat transfer calculation during main steam line break for Maanshan PWR plant

    Energy Technology Data Exchange (ETDEWEB)

    Yuann, Yng-Ruey, E-mail: ryyuann@iner.gov.tw; Kao, Lain-Su, E-mail: lskao@iner.gov.tw

    2013-10-15

    Highlights: • Evaluate component cooling water (CCW) thermal response during MSLB for Maanshan. • Using GOTHIC to calculate CCW temperature and determine time required to boil CCW. • Both convective and condensation heat transfer from the air side are considered. • Boiling will not occur since T{sub B} is sufficiently longer than CCW pump restart time. -- Abstract: A thermal analysis has been performed for the Containment Fan Cooler Unit (FCU) during Main Steam Line Break (MSLB) accident, concurrent with loss of offsite power, for Maanshan PWR plant. The analysis is performed in order to address the waterhammer and two-phase flow issues discussed in USNRC's Generic Letter 96-06 (GL 96-06). Maanshan plant is a twin-unit Westinghouse 3-loop PWR currently operated at rated core thermal power of 2822 MWt for each unit. The design basis for containment temperature is Main Steam Line Break (MSLB) accident at power of 2830.5 MWt, which results in peak vapor temperature of 387.6 °F. The design is such that when MSLB occurs concurrent with loss of offsite power (MSLB/LOOP), both the coolant pump on the secondary side and the fan on the air side of the FCU loose power and coast down. The pump has little inertia and coasts down in 2–3 s, while the FCU fan coasts down over much longer period. Before the pump is restored through emergency diesel generator, there is potential for boiling the coolant in the cooling coils by the high-temperature air/steam mixture entering the FCU. The time to boiling depends on the operating pressure of the coolant before the pump is restored. The prediction of the time to boiling is important because it determines whether there is potential for waterhammer or two-phase flow to occur before the pump is restored. If boiling occurs then there exists steam region in the pipe, which may cause the so called condensation induced waterhammer or column closure waterhammer. In either case, a great amount of effort has to be spent to

  9. Mutualistic fungal endophytes produce phytohormones and organic acids that promote japonica rice plant growth under prolonged heat stress.

    Science.gov (United States)

    Waqas, Muhammad; Khan, Abdul Latif; Shahzad, Raheem; Ullah, Ihsan; Khan, Abdur Rahim; Lee, In-Jung

    2015-12-01

    This study identifies the potential role in heat-stress mitigation of phytohormones and other secondary metabolites produced by the endophytic fungus Paecilomyces formosus LWL1 in japonica rice cultivar Dongjin. The japonica rice was grown in controlled chamber conditions with and without P. formosus LWL1 under no stress (NS) and prolonged heat stress (HS) conditions. Endophytic association under NS and HS conditions significantly improved plant growth attributes, such as plant height, fresh weight, dry weight, and chlorophyll content. Furthermore, P. formosus LWL1 protected the rice plants from HS compared with controls, indicated by the lower endogenous level of stress-signaling compounds such as abscisic acid (25.71%) and jasmonic acid (34.57%) and the increase in total protein content (18.76%-33.22%). Such fungal endophytes may be helpful for sustainable crop production under high environmental temperatures.

  10. Compact heat exchanger for power plants; Kompakti siirrin tyoentyy myoes kotimaan voimalaitoksiin

    Energy Technology Data Exchange (ETDEWEB)

    Kinnunen, L. [Energia-lehti, Helsinki (Finland)

    2001-07-01

    Vahterus Oy, located at Kalanti, has manufactured heat exchangers since the beginning of 1990s. About 90% of the equipment produced are exported. In the PSHE (Plate and Shell) solution of the Vahterus heat exchanger the heat is transferred by round plated welded to form a compact package, which is assembled into a cylindrical steel casing. The heat exchanger contains no gaskets or soldered joints, which eliminates the leak risks. Traditional heat exchanges are usually operated at higher temperatures and pressures, but the heat transfer capacities of them are lower. Plate heat exchangers, on the other hand, are efficient, but the application range of them is narrow. Additionally, the rubber gasket of the heat exchange plates, sealing the joints of the heat exchanging plates, does not stand high pressures or temperatures, or corroding fluids. The new welded plate heat exchanger combine the pressure and temperature resistance of tube heat exchangers and the high heat exchange capacity of plate heat exchangers. The new corrosion resisting heat exchanger can be applied for especially hard conditions. The operating temperature range of the PSHE heat exchanger is - 200 - 900 deg C. The pressure resistance is as high as 100 bar. The space requirement of PSHE is only one tenth of the space requirement of traditional tube heat exchangers. Adjusting the number of heat exchanging plates can change the capacity of the heat exchanger. Power range of the heat exchanger can be as high as 80 MW. Due to the corrosion preventive construction and the small dimension the PSHE heat exchanger can be applied for refrigerators using ammonia as refrigerant. These kinds of new Vahterus heat exchangers are in use in 60 countries in more than 2000 refrigerators.

  11. Timing effects of heat-stress on plant physiological characteristics and growth: a field study with prairie vegetation

    Directory of Open Access Journals (Sweden)

    Dan Wang

    2016-11-01

    Full Text Available More intense, more frequent, and longer heat-waves are expected in the future due to global warming, which could have dramatic agricultural, economic and ecological impacts. This field study examined how plant responded to heat-stress (HS treatment at different timing in naturally-occurring vegetation. HS treatment (5 days at 40.5 ºC were applied to 12 1m2 plots in restored prairie vegetation dominated by Andropogon gerardii (warm-season C4 grass and Solidago canadensis (warm-season C3 forb at different growing stages. During and after HS, air, canopy, and soil temperature were monitored; net CO2 assimilation (Pn, quantum yield of photosystem II (ФPSII, stomatal conductance (gs, and internal CO2 level (Ci of the dominant species were measured. One week after the last HS treatment, all plots were harvested and the biomass of above-ground tissue and flower weight of the two dominant species was determined. HS decreased physiological performance and growth for both species, with S. canadensis being affected more than A. gerardii, indicated by negative heat stress effect on both physiological and growth responses. There were significant timing effect of heat stress on the two species, with greater reductions in the photosynthesis and productivity occurred when heat stress was applied at later-growing season. The reduction in aboveground productivity in S. canadensis but not A. gerardii could have important implications for plant community structure by increasing the competitive advantage of A. gerardii in this grassland. The present experiment showed that heat stress, though ephemeral, may promote long-term effects on plant community structure, vegetation dynamics, biodiversity, and ecosystem functioning of terrestrial biomes when more frequent and severe heat stress occur in the future.

  12. Dense gas in the Galactic central molecular zone is warm and heated by turbulence

    CERN Document Server

    Ginsburg, Adam; Ao, Yiping; Riquelme, Denise; Kauffmann, Jens; Pillai, Thushara; Mills, Elisabeth A C; Requena-Torres, Miguel A; Immer, Katharina; Testi, Leonardo; Ott, Juergen; Bally, John; Battersby, Cara; Darling, Jeremy; Aalto, Susanne; Stanke, Thomas; Kendrew, Sarah; Kruijssen, J M Diederik; Longmore, Steven; Dale, James; Guesten, Rolf; Menten, Karl M

    2016-01-01

    The Galactic center is the closest region in which we can study star formation under extreme physical conditions like those in high-redshift galaxies. We measure the temperature of the dense gas in the central molecular zone (CMZ) and examine what drives it. We mapped the inner 300 pc of the CMZ in the temperature-sensitive J = 3-2 para-formaldehyde (p-H$_2$CO) transitions. We used the $3_{2,1} - 2_{2,0} / 3_{0,3} - 2_{0,2}$ line ratio to determine the gas temperature in $n \\sim 10^4 - 10^5 $cm$^{-3}$ gas. We have produced temperature maps and cubes with 30" and 1 km/s resolution and published all data in FITS form. Dense gas temperatures in the Galactic center range from ~60 K to > 100 K in selected regions. The highest gas temperatures T_G > 100 K are observed around the Sgr B2 cores, in the extended Sgr B2 cloud, the 20 km/s and 50 km/s clouds, and in "The Brick" (G0.253+0.016). We infer an upper limit on the cosmic ray ionization rate ${\\zeta}_{CR} < 10^{-14}$ 1/s. The dense molecular gas temperature o...

  13. Water as carrier of information of heat shock and drug effect between two groups of Adhatoda vasica plants

    Directory of Open Access Journals (Sweden)

    N C Sukul

    2012-06-01

    Full Text Available Adhatoda vasica Nees plants were grown in 50 earthen pots, which were divided into 5 batches A, B, C, D, and E. Of these A, B and C, D were arranged into two separate parallel pairs. One leaf of each plant of an adjacent pair was immersed in sterile tap water in a beaker. Adjacent beakers in each pair A B or C D were connected by polythene tubes containing wet cotton threads. One leaf of each plant of A was given heat shock by immersing a leaf in hot water for 5 min. One leaf of each plant of C was treated with Cantharis vesicatoria 200c. Batch E served as the unstressed and untreated control. One hour after heat shock or drug treatment all the leaves were harvested and their proteins were extracted by chilled protein extraction buffer. Proteins were separated by Fast Protein Liquid Chromatography (FPLC. Protein profiles of A, B and C, D showed marked similarity with respect to expression and repression of some proteins. It is concluded that the effect of heat shock and drug treatment is transmitted through water in the capillaries of cotton threads connecting the pairs of plants. It is assumed that heat shock or drug treatment altered locally the water structure in the leaves which was propagated through global network of water structure over the protein network in the whole plants, and from there to the interfacial water in the beakers and cotton threads. A homeopathic potency is thought to be specifically structured water which influences the water structure in the treated organism.

  14. The cost of installing central heating. Comparison of Norway and Sweden. Final version; Kostnader ved installasjon av vannbaaren varme. Sammenlikning av Norge og Sverige. Endelig versjon

    Energy Technology Data Exchange (ETDEWEB)

    Haarberg, Karl Johan; Elnan, Kaare; Essen, Jan von; Hovden, Agnete; Ekvall, Thomas; Melbaeck, Johan

    2010-10-22

    The objective of the cost study is to examine costs and cost differences associated with the installation of various technical solutions for water heating in various buildings in Norway and Sweden - regionally and nationally. In addition, the cost study intended to point out any barriers to the increased prevalence of central heating, as well as proposals for measures to remove such. Finally, the cost study in general and in particular barriers placed in a larger environment and climate perspective. (AG)

  15. Elecnuc. Nuclear power plants in the world; Elecnuc. Les centrales nucleaires dans le monde

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This small booklet summarizes in tables all data relative to the nuclear power plants worldwide. These data come from the IAEA's PRIS and AREVA-CEA's GAIA databases. The following aspects are reviewed: 2007 highlights; Main characteristics of reactor types; Map of the French nuclear power plants on 2007/01/01; Worldwide status of nuclear power plants (12/31/2007); Units distributed by countries; Nuclear power plants connected to the Grid- by reactor type groups; Nuclear power plants under construction on 2007; Evolution of nuclear power plants capacities connected to the grid; First electric generations supplied by a nuclear unit in each country; Electrical generation from nuclear power plants by country at the end 2007; Performance indicator of French PWR units; Evolution of the generation indicators worldwide by type; Nuclear operator ranking according to their installed capacity; Units connected to the grid by countries at 12/31/2007; Status of licence renewal applications in USA; Nuclear power plants under construction at 12/31/2007; Shutdown reactors; Exported nuclear capacity in net MWe; Exported and national nuclear capacity connected to the grid; Exported nuclear power plants under construction; Exported and national nuclear capacity under construction; Nuclear power plants ordered at 12/31/2007; Long term shutdown units at 12/31/2007; COL (combined licences) applications in the USA; Recycling of Plutonium in reactors and experiences; Mox licence plants projects; Appendix - historical development; Meaning of the used acronyms; Glossary.

  16. Heating, ventilating, and air conditioning deactivation thermal analysis of PUREX Plant

    Energy Technology Data Exchange (ETDEWEB)

    Chen, W.W.; Gregonis, R.A. [Westinghouse Hanford Company, Richland, WA (United States)

    1997-08-01

    Thermal analysis was performed for the proposed Plutonium Uranium Extraction Plant exhaust system after deactivation. The purpose of the analysis was to determine if enough condensation will occur to plug or damage the filtration components. A heat transfer and fluid flow analysis was performed to evaluate the thermal characteristics of the underground duct system, the deep-bed glass fiber filter No. 2, and the high-efficiency particulate air filters in the fourth filter building. The analysis is based on extreme variations of air temperature, relative humidity, and dew point temperature using 15 years of Hanford Site weather data as a basis. The results will be used to evaluate the need for the electric heaters proposed for the canyon exhaust to prevent condensation. Results of the analysis indicate that a condition may exist in the underground ductwork where the duct temperature can lead or lag changes in the ambient air temperature. This condition may contribute to condensation on the inside surfaces of the underground exhaust duct. A worst case conservative analysis was performed assuming that all of the water is removed from the moist air over the inside surface of the concrete duct area in the fully developed turbulent boundary layer while the moist air in the free stream will not condense. The total moisture accumulated in 24 hours is negligible. Water puddling would not be expected. The results of the analyses agree with plant operating experiences. The filters were designed to resist high humidity and direct wetting, filter plugging caused by slight condensation in the upstream duct is not a concern. 19 refs., 2 figs.

  17. Possible role of growth regulators in adaptation to heat stress affecting partitioning of photosynthates in tomato plants

    Directory of Open Access Journals (Sweden)

    Zofia Starck

    2014-01-01

    Full Text Available Tomato plants of two cultivars: Roma - sensitive and Robin - tolerant to heat stress were grown in greenhouse up to the flowering stage and then under controlled environmen­tal conditions. The partitioning of recently fixed 14CO2 by mature tomato leaves was examined as a posteffect of 24-h heat stress (38/25°C day/night with the interaction of growth regulators (GR sprayed on the flowers with solution of β-naphthoxyacetic (NOA and gibberellic (GA3 acid (denoted as NG, or Zeatin + NOA + GA3 (denoted as ZNG. In both cuitivars GR strongly stimulated fruit growth and transport of 14C-photosynthates to the clusters at the expense of vegetative organs. Heat stress decreased export of 14C-phoiosynthates from the blades in plants not treated with GR, but even more in cv. Roma. In Roma plants not treated with GR (with very small fruitlets and fruits the heat stress retarded 14C-transport just in the petioles, diminishing the 14C-supply to the fruits. Reduction of the current photosynthate supplied to the fruits seems to be causally connected with inhibition of the specific activity of acid invertase in that organ. Growth regulators reduced the negative effect of high temperature - they alleviated depression of 14C-export from the blades and increased invertase activity. 14C-photosynthate transport to the fruits, presumably owing to their higher sink strength, was less affected by heat stress. In Robin plants (which had bigger fruits during the experiment high temperature depressed 14C-fruit supply only in the NG-series, in contrast to enhacement of 14C-Movement to that sink in the control and ZNG-series. In spite of these facts, after heat stress, the specific activity of acid invertase decreased in all the experimental series, but much less in the GR-treated series. Therefore, in the Robin cv. there was no relation between invertase activity and 14C-mobilization by fruits, as was observed in Roma plants. The possible explanation of the different

  18. Modeling a Printed Circuit Heat Exchanger with RELAP5-3D for the Next Generation Nuclear Plant

    Energy Technology Data Exchange (ETDEWEB)

    2010-12-01

    The main purpose of this report is to design a printed circuit heat exchanger (PCHE) for the Next Generation Nuclear Plant and carry out Loss of Coolant Accident (LOCA) simulation using RELAP5-3D. Helium was chosen as the coolant in the primary and secondary sides of the heat exchanger. The design of PCHE is critical for the LOCA simulations. For purposes of simplicity, a straight channel configuration was assumed. A parallel intermediate heat exchanger configuration was assumed for the RELAP5 model design. The RELAP5 modeling also required the semicircular channels in the heat exchanger to be mapped to rectangular channels. The initial RELAP5 run outputs steady state conditions which were then compared to the heat exchanger performance theory to ensure accurate design is being simulated. An exponential loss of pressure transient was simulated. This LOCA describes a loss of coolant pressure in the primary side over a 20 second time period. The results for the simulation indicate that heat is initially transferred from the primary loop to the secondary loop, but after the loss of pressure occurs, heat transfers from the secondary loop to the primary loop.

  19. Numerical modelling of distribution the discharged heat water from thermal power plant on the aquatic environment

    Science.gov (United States)

    Issakhov, Alibek

    2016-06-01

    The paper presents a mathematical model of distribution the discharged heat water from thermal power plant under various operational capacities on the aquatic environment. It was solved by the Navier-Stokes and temperature equations for an incompressible fluid in a stratified medium were based on the splitting method by physical parameters which approximated by the finite volume method. The numerical solution of the equation system was divided into four stages. At the first step it was assumed that the momentum transfer carried out only by convection and diffusion. While the intermediate velocity field was solved by 5-step Runge-Kutta method. At the second stage, the pressure field was solved by found the intermediate velocity field. Whereas Poisson equation for the pressure field was solved by Jacobi method. The third step assumes that the transfer was carried out only by pressure gradient. Finally the fourth step of the temperature equation was also solved as motion equations, with 5-step Runge-Kutta method. The algorithm was parallelized on high-performance computer. The obtained numerical results of three-dimensional stratified turbulent flow were compared with experimental data. What revealed qualitatively and quantitatively approximately the basic laws of hydrothermal processes occurring in the reservoir-cooler.

  20. Response of four foliage plants to heated soil and reduced air temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Bodnaruk, W.H. Jr.; Mills, T.W.; Ingram, D.L.

    1981-01-01

    Tip cuttings of Dieffenbachia maculata (Lodd.) G. Donn Exotic Perfection Compacta' and Aglaonema commutatum Schott Silver Queen and single eye cuttings of Epipremnum aureum (Linden and Andre) Bunt, and Philodendron scandens oxycardium (Schott) Bunt. were propagated in combinations of 4 minimum air temperatures, 45/sup 0/, 50/sup 0/, 55/sup 0/ and 60/sup 0/F (7.2/sup 0/, 10/sup 0/, 12.7/sup 0/, 15.5/sup 0/C), and 2 soil temperature treatments; controlled 70/sup 0/F (21/sup 0/C) minimum and variable. Maintaining minimum soil temperatures at 70/sup 0/F reduced production times for rooted Dieffenbachia and Aglaonema tips by 45% and of Epipremnum and Philodendron suitable for 3 inch pots by 35% and 25%, respectively, regardless of minimum air temperature. Minimum air temperature had little effect on Dieffenbachia or Aglaonema root number and length at 70/sup 0/F soil temperature. Similarly shoot length and number of leaves of Philodendron and Epipremnum were not affected by minimum air temperatures with 70/sup 0/F soil temperature. Plant quality was uniformly high in all crops at the 70/sup 0/F soil minimum for all air temperatures except Epipremnum which was chlorotic at 45/sup 0/F. A description of a warm water in-benching heating system is included. 6 references, 2 figures, 9 tables.

  1. Comparison of Tobacco Host Cell Protein Removal Methods by Blanching Intact Plants or by Heat Treatment of Extracts.

    Science.gov (United States)

    Buyel, Johannes F; Hubbuch, Jürgen; Fischer, Rainer

    2016-01-01

    Plants not only provide food, feed and raw materials for humans, but have also been developed as an economical production system for biopharmaceutical proteins, such as antibodies, vaccine candidates and enzymes. These must be purified from the plant biomass but chromatography steps are hindered by the high concentrations of host cell proteins (HCPs) in plant extracts. However, most HCPs irreversibly aggregate at temperatures above 60 °C facilitating subsequent purification of the target protein. Here, three methods are presented to achieve the heat precipitation of tobacco HCPs in either intact leaves or extracts. The blanching of intact leaves can easily be incorporated into existing processes but may have a negative impact on subsequent filtration steps. The opposite is true for heat precipitation of leaf extracts in a stirred vessel, which can improve the performance of downstream operations albeit with major changes in process equipment design, such as homogenizer geometry. Finally, a heat exchanger setup is well characterized in terms of heat transfer conditions and easy to scale, but cleaning can be difficult and there may be a negative impact on filter capacity. The design-of-experiments approach can be used to identify the most relevant process parameters affecting HCP removal and product recovery. This facilitates the application of each method in other expression platforms and the identification of the most suitable method for a given purification strategy.

  2. Adjustment of machine equipment in heating plants to facilitate addition of straw fuel; Anpassning av vaermeverksutrustning till halminblandning

    Energy Technology Data Exchange (ETDEWEB)

    Stridsberg, Sven [BIOSYD (Sweden)

    1999-10-01

    The ground of the project is a development work, carried out by BIOSYD according combustion of straw in heating plants. First we have handled combustion experiments with addition of straw in some plants working with wood fuels, mainly with good results. In the next step we have worked with new techniques for handling and delivery of straw to the plants, also including experiments with chopping of the straw on the field, storing it in outdoor uncovered piles and consequently delivered in the shape of 'chips' to the heating plant. The whole cycle from cutting to combustion has been checked. The results indicate a possible price of the straw at the heating plant of approx 85 SEK/MWh, which can easily compete with wood fuels. The present project will describe which adjustments of the machine equipment are needed to allow a 25 % addition of straw in the fuel mix, how much these adjustments will cost and if they should be profitable in competition with wood fuels for 110 SEK/MWh. In total 37 heating plants from Skaane up to Uppland have been visited and the process from fuel reception to combustion analyzed. The costs of adjustments needed have been calculated from similar examples. The main impression from the studies is that the fuel reception has too small volumes to allow more numerous kinds of fuel and specially make it possible to give a good mix. This is often not critical for wood fuels but for straw we must guarantee a good mix to get a good combustion. Other critical points are crossings between conveyors, for example dips and feeding out devices, which often have to be adjusted. In the combustion there is a risk for sintering as well as coatings on tubes and walls. These functions must be avoided by air distribution, feed back of fuel gas and better carbon removing. In our analyses we would have judged on results from practical tests, but as this would have been too extensive, we must trust in former experiences, transferred to respective plants. Our

  3. Quality Assurance in Nuclear Power Plants; La garantia de calidad en la Centrales Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Zamarron Casinello, J. M. (CC.AA. Almaraz-Trillo); Gasca Pinilla, R. (Asociacion Nuclear Asco-Vandellos II); Sala Candela, A. (IBERDROLA); Valle Pena (NUCLENOR); Ruiz Rodriguez, C. (UNION FENOSA)

    2000-07-01

    In 1970, 10CFR50 Appendix B. Quality Assurance Criteria for Nuclear Power Plants & Fuel Reprocessing Plants, was approved in USA. This is based on 18 criteria and requires American nuclear power plants to establish as quickly as possible a Quality Assurance Program (QAP) specifying how to comply with the criteria contained in this Appendix. The Ministry of Industry required that this standard be observed in Spanish plants. In The first-generation plants (Jose Cabrera, Santa Maria de Garona and Vandellos 1), which were built before this new standard was developed, the concept of Quality Assurance has only been applied to the operating phase, whereas in second-generation plants (Almaraz, Asco3 and Cofrentes) and third-generation plants (Vandellos 2 and Trillo), the concept was applied from the very beginning of the project: design phases, construction and finally plant operation. In 1979, the IAEA publihed practical code 50-C-QA as an international reference document. It contains 13 criteria that coincide with and complement those established in Appendex B of 10CFR50. As a result, the nuclear power plants in all neighboring countries will be enforcing similar Quality Assurance criteria. (Author)

  4. Possible role of growth regulators in adaptation to heat stress affecting partitioning of photosynthates in tomato plants

    OpenAIRE

    Zofia Starck; Elżbieta Cieśla

    2014-01-01

    Tomato plants of two cultivars: Roma - sensitive and Robin - tolerant to heat stress were grown in greenhouse up to the flowering stage and then under controlled environmen­tal conditions. The partitioning of recently fixed 14CO2 by mature tomato leaves was examined as a posteffect of 24-h heat stress (38/25°C day/night) with the interaction of growth regulators (GR) sprayed on the flowers with solution of β-naphthoxyacetic (NOA) and gibberellic (GA3) acid (denoted as NG), or Zeatin + NOA + G...

  5. The operation of small cogeneration plants and short-term storage for district heating and public electric power

    DEFF Research Database (Denmark)

    Ilkjær, J; Petersen, P.M.; Qvale, Einar Bjørn

    1989-01-01

    A theoretical investigation of the economics of cogeneration supplemented by warm-water storage and subjected to a three-step price schedule for electricity, has been carried out. Some general guidelines can be derived, but no simple design rules, such as those for cogeneration plants operating...... with a two-step schedule, seem to govern the design of such plants subjected to the new conditions. Simulation studies have been initiated in order to arrive at sufficiently accurate optimal store dimensions and operational strategy. The results from simulation studies which give the store as a function...... of cogeneration plant size relative to the total heat demand in the geographical region supplied by the plant are shown...

  6. Observations on flowering plants in north central Florida that might serve as nectar sites.

    Science.gov (United States)

    Observations were made on the seasonal phenology of flowering plants along SR24 between Gainesville and Cedar Key, FL, for a period of 1 yr. The objective was to document the seasonality, species composition and relative abundance of flowering plants that might be available as nectar sites for mosq...

  7. Environmental Management System of Thermal plants: SIGMA; El sistema de gestion medioambiental de centrales termicas: SIGMA

    Energy Technology Data Exchange (ETDEWEB)

    Mateo Montoya, I.; Rodriguez Zarzalejos, A.

    1995-04-01

    SIGMA, (Sistema de Gestion Medioambiental) this Environmental Management System includes the different factors that are present in the environmental management of a conventional Thermal Plant such as: Air and Water Pollution, Hazardous Waste Management, Energy Recovery and Control of the Environmental Impact. Up to date the section Air Pollution is being developed and set up in the Thermal Plant of Meirama. (Author)

  8. Working in a virtual power plant; Travailler dans une centrale virtuelle

    Energy Technology Data Exchange (ETDEWEB)

    Thibault, G.; Smadja, S

    1999-07-01

    Graphical simulations on computer providing a virtual and reversible experience can now be used for maintenance in nuclear power plants allowing operations to be tested and tools to be optimised. Eventually, operatives will be trained to work in virtual nuclear power plants in complete safety. (authors)

  9. Altitudinal Pattern of Plant Species Diversity in Shennongjia Mountains, Central China

    Institute of Scientific and Technical Information of China (English)

    Chang-Ming ZHAO; Wei-Lie CHEN; Zi-Qiang TIAN; Zong-Qiang XIE

    2005-01-01

    One hundred and sixty plots, approximately every 100 m above sea level (a.s.l.) along an altitudinal gradient from 470 to 3 080 m a.s.l, at the southern and northern watershed of Mt. Shennongjia,China, were examined to determine the altitudinal pattern of plant species diversity. Mt. Shennongjia was found to have high plant species diversity, with 3 479 higher plants recorded. Partial correlation analysis and detrended canonical correspondence analysis (DCCA) based on plant species diversity revealed that altitude was the main factor affecting the spatial pattern of plant species diversity on Mt. Shennongjia and that canopy coverage of the arbor layer also had a considerable effect on plant species diversity. The DCCA based on species data of importance value further revealed that altitude gradient was the primary factor shaping the spatial pattern of plant species. In addition, the rule of the "mid-altitude bulge" was supported on Mt. Shennongjia. Plant species diversity was closely related to vegetation type and the transition zone usually had a higher diversity. Higher plant species diversity appeared in the mixed evergreen and deciduous broadleaved forest zone (900-1 500 m a.s.l.) and its transition down to evergreen broadleaved forest zone or up to deciduous broadleaved forest zone. The largest plant species diversity in whole communities on Mt. Shennongjia lay at approximately 1 200 m a.s.l. Greatest tree diversity, shrub diversity, and grass diversity was found at approximately 1 500, 1 100, and 1 200 m a.s.l., respectively. The southern watershed showed higher plant species diversity than the northern watershed, with maximum plant species diversity at a higher altitude in the southern watershed than the northern watershed. These results indicate that Mt.Shennongjia shows characteristics of a transition region. The relationship between the altitudinal pattern of plant species diversity and the vegetation type in eastern China are also discussed and a

  10. Enhanced drought and heat stress tolerance of tobacco plants with ectopically enhanced cytokinin oxidase/dehydrogenase gene expression.

    Science.gov (United States)

    Macková, Hana; Hronková, Marie; Dobrá, Jana; Turečková, Veronika; Novák, Ondřej; Lubovská, Zuzana; Motyka, Václav; Haisel, Daniel; Hájek, Tomáš; Prášil, Ilja Tom; Gaudinová, Alena; Štorchová, Helena; Ge, Eva; Werner, Tomáš; Schmülling, Thomas; Vanková, Radomíra

    2013-07-01

    Responses to drought, heat, and combined stress were compared in tobacco (Nicotiana tabacum L.) plants ectopically expressing the cytokinin oxidase/dehydrogenase CKX1 gene of Arabidopsis thaliana L. under the control of either the predominantly root-expressed WRKY6 promoter or the constitutive 35S promoter, and in the wild type. WRKY6:CKX1 plants exhibited high CKX activity in the roots under control conditions. Under stress, the activity of the WRKY6 promoter was down-regulated and the concomitantly reduced cytokinin degradation coincided with raised bioactive cytokinin levels during the early phase of the stress response, which might contribute to enhanced stress tolerance of this genotype. Constitutive expression of CKX1 resulted in an enlarged root system, a stunted, dwarf shoot phenotype, and a low basal level of expression of the dehydration marker gene ERD10B. The high drought tolerance of this genotype was associated with a relatively moderate drop in leaf water potential and a significant decrease in leaf osmotic potential. Basal expression of the proline biosynthetic gene P5CSA was raised. Both wild-type and WRKY6:CKX1 plants responded to heat stress by transient elevation of stomatal conductance, which correlated with an enhanced abscisic acid catabolism. 35S:CKX1 transgenic plants exhibited a small and delayed stomatal response. Nevertheless, they maintained a lower leaf temperature than the other genotypes. Heat shock applied to drought-stressed plants exaggerated the negative stress effects, probably due to the additional water loss caused by a transient stimulation of transpiration. The results indicate that modulation of cytokinin levels may positively affect plant responses to abiotic stress through a variety of physiological mechanisms.

  11. Effect of volume loading on the Frank-Starling relation during reductions in central blood volume in heat-stressed humans

    DEFF Research Database (Denmark)

    Bundgaard-Nielsen, Morten; Wilson, T E; Seifert, Thomas

    2010-01-01

    During reductions in central blood volume while heat stressed, a greater decrease in stroke volume (SV) for a similar decrease in ventricular filling pressure, compared to normothermia, suggests that the heart is operating on a steeper portion of a Frank-Starling curve. If so, volume loading of h...

  12. 中央热送风冲天炉的应用%Application of Central Blast-heating Cupola

    Institute of Scientific and Technical Information of China (English)

    冯英宇; 苏文生

    2011-01-01

    为提高冲天炉的综合性能,通过采取中央集中送风,合理控制风口风速,合理的炉膛结构,防止风嘴熔化等措施.强化焦炭燃烧,增加了焦炭的燃烧比,提高了冲天炉熔炼铁液的出炉温度;能适用混合焦炭,简化了焦炭处理;使炉衬侵蚀减小,修炉简便.通过多年实践改进,完善了中央送风冲天炉的相关工艺参数.该炉型操作简单,有利于降低硅、锰烧损和节能,打炉方便,生产稳定,可在同行业推广.%To improve the overall performance of cupola, taking the measures of centralized air supply, reasonable air control speed, reasonable furnace structurc and preventing the tuyere from mclting, the process of coke combustion is enhanced, the combustion ratio of coke increases and the tapping temperature of cupola melting iron improves. Mixed coke can be applied under the above measures, so the coke processing is simplified, which reduces lining erosion, makes repairing furnace simple. Through practicing and improving in years, the relevant process parameters of central blast-heating cupola are perfected. The cupola is simple in work and stable in production, which can reduce silicon-manganese melting loss and save energy. The cupola is worth of spreading in the same industry.

  13. Isobar gas and steam. Compressed air storage plant with heat storage; Isobares GuD. Druckluftspeicherkraftwrk mit Waermespeicher

    Energy Technology Data Exchange (ETDEWEB)

    Schlitzberger, Christian; Leithner, Reinhard; Nielsen, Lasse [Technische Univ. Braunschweig (Germany). Inst. fuer Waerme- und Brennstofftechnik

    2008-07-01

    Due to the worldwide increasing energy consumption the unfavourable aspects of the today's power supply structure are strengthened continuously. There are two compressed air energy storage power stations existing. However, these power stations exhibit worse efficiencies of storage in comparison to existing pumped-storage power plants. In order to avoid this disadvantage, a concept of a isobaric gas and steam compressed air storage plant was developed at the institute for heat and fuel technology at the technical university of Braunschweig. This concept is presented in the contribution under consideration.

  14. Elecnuc. Nuclear power plants in the world; Elecnuc. Les centrales nucleaires dans le monde

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    This small booklet summarizes in tables all the numerical data relative to the nuclear power plants worldwide. These data come from the French CEA/DSE/SEE Elecnuc database. The following aspects are reviewed: 1999 highlights; main characteristics of the reactor types in operation, under construction or on order; map of the French nuclear power plants; worldwide status of nuclear power plants at the end of 1999; nuclear power plants in operation, under construction and on order; capacity of nuclear power plants in operation; net and gross capacity of nuclear power plants on the grid and in commercial operation; grid connection forecasts; world electric power market; electronuclear owners and share holders in EU, capacity and load factor; first power generation of nuclear origin per country, achieved or expected; performance indicator of PWR units in France; worldwide trend of the power generation indicator; 1999 gross load factor by operator; nuclear power plants in operation, under construction, on order, planned, cancelled, shutdown, and exported; planning of steam generators replacement; MOX fuel program for plutonium recycling. (J.S.)

  15. Agroforestry leads to shifts within the gammaproteobacterial microbiome of banana plants cultivated in Central America.

    Science.gov (United States)

    Köberl, Martina; Dita, Miguel; Martinuz, Alfonso; Staver, Charles; Berg, Gabriele

    2015-01-01

    Bananas (Musa spp.) belong to the most important global food commodities, and their cultivation represents the world's largest monoculture. Although the plant-associated microbiome has substantial influence on plant growth and health, there is a lack of knowledge of the banana microbiome and its influencing factors. We studied the impact of (i) biogeography, and (ii) agroforestry on the banana-associated gammaproteobacterial microbiome analyzing plants grown in smallholder farms in Nicaragua and Costa Rica. Profiles of 16S rRNA genes revealed high abundances of Pseudomonadales, Enterobacteriales, Xanthomonadales, and Legionellales. An extraordinary high diversity of the gammaproteobacterial microbiota was observed within the endophytic microenvironments (endorhiza and pseudostem), which was similar in both countries. Enterobacteria were identified as dominant group of above-ground plant parts (pseudostem and leaves). Neither biogeography nor agroforestry showed a statistically significant impact on the gammaproteobacterial banana microbiome in general. However, indicator species for each microenvironment and country, as well as for plants grown in Coffea intercropping systems with and without agri-silvicultural production of different Fabaceae trees (Inga spp. in Nicaragua and Erythrina poeppigiana in Costa Rica) could be identified. For example, banana plants grown in agroforestry systems were characterized by an increase of potential plant-beneficial bacteria, like Pseudomonas and Stenotrophomonas, and on the other side by a decrease of Erwinia. Hence, this study could show that as a result of legume-based agroforestry the indigenous banana-associated gammaproteobacterial community noticeably shifted.

  16. Traditional Uses of Plants in the Tolfa–Cerite–Manziate Area (Central Italy

    Directory of Open Access Journals (Sweden)

    Paolo Maria Guarrera

    2015-09-01

    Full Text Available Traditional knowledge of local plant uses is rapidly fading away, especially in rural Mediterranean areas. We carried out ethnobotanical research in 2010-2011 in order to investigate the local knowledge of wild plants in the Tolfa–Cerite–Manziate area of Italy (Latium, district of Rome. We carried out a total of 45 semi-structured interviews with farmers, herders, and fishers. Here, a simple diachronic comparison is made between the current study and a previous one conducted in some of the villages of the study area to highlight potential losses of traditional knowledge of local plants. We documented a total of 102 plant species, belonging to 48 families, along with their uses (excluding food uses. We also reported some non-plant based remedies that were primarily used in veterinary medicine. Some plant uses, especially for making handicrafts, have not been reported previously (e.g., those of Celtis australis L. Cannabaceae, Betula pendula Roth Betulaceae. Many plant uses are no longer remembered in the area, which indicates a loss of local ethnobotanical knowledge.

  17. Does plant immunity have a central role in the legume rhizobium symbiosis?

    Directory of Open Access Journals (Sweden)

    Katalin eToth

    2015-06-01

    Full Text Available Plants are exposed to many different microbes in their habitat. These microbes may be benign or pathogenic, but in some cases they are beneficial. The rhizosphere provides an especially rich palette for colonization by beneficial (associative and symbiotic microorganisms, which raises the question as to how roots can distinguish such ‘friends’ from possible ‘foes’ (i.e., pathogens. Plants possess an innate immunity system that can recognize pathogens, through an arsenal of protein receptors. These receptors include receptor-like kinases (RLK and receptor-like proteins (RLP located at the plasma membrane, as well as intracellular receptors (so called NBS-LRR proteins or R proteins that recognize molecules released by microbes into the plant cell. The key rhizobial, symbiotic signaling molecule (called Nod factor is perceived by the host legume plant using LysM-domain containing RLKs. Perception of the symbiotic Nod factor triggers signaling cascades leading to bacterial infection and accommodation of the symbiont in a newly formed root organ, the nodule, resulting in a nitrogen-fixing root nodule symbiosis (RNS. The net result of this symbiosis is the intracellular colonization of the plant with thousands of bacteria; a process that seems to occur in spite of the immune ability of plants to prevent pathogen infection. In this review, we discuss the potential of the invading rhizobial symbiont to actively avoid this innate immunity response, as well as specific examples of where the plant immune response may modulate rhizobial infection and host range.

  18. Agroforestry leads to shifts within the gammaproteobacterial microbiome of banana plants cultivated in Central America

    Directory of Open Access Journals (Sweden)

    Martina eKöberl

    2015-02-01

    Full Text Available Bananas (Musa spp. belong to the most important global food commodities, and their cultivation represents the world’s largest monoculture. Although the plant-associated microbiome has substantial influence on plant growth and health, there is a lack of knowledge of the banana microbiome and its influencing factors. We studied the impact of i biogeography, and ii agroforestry on the banana-associated gammaproteobacterial microbiome analyzing plants grown in smallholder farms in Nicaragua and Costa Rica. Profiles of 16S rRNA genes revealed high abundances of Pseudomonadales, Enterobacteriales, Xanthomonadales, and Legionellales. An extraordinary high diversity of the gammaproteobacterial microbiota was observed within the endophytic microenvironments (endorhiza and pseudostem, which was similar in both countries. Enterobacteria were identified as dominant group of above-ground plant parts (pseudostem and leaves. Neither biogeography nor agroforestry showed a statistically significant impact on the gammaproteobacterial banana microbiome in general. However, indicator species for each microenvironment and country, as well as for plants grown in Coffea intercropping systems with and without agri-silvicultural production of different Fabaceae trees (Inga spp. in Nicaragua and Erythrina poeppigiana in Costa Rica could be identified. For example, banana plants grown in agroforestry systems were characterized by an increase of potential plant-beneficial bacteria, like Pseudomonas and Stenotrophomonas, and on the other side by a decrease of Erwinia. Hence, this study could show that as a result of legume-based agroforestry the indigenous banana-associated gammaproteobacterial community noticeably shifted.

  19. Preliminary design of the Carrisa Plains solar central receiver power plant. Volume III, Book 3. Appendices, Part 1

    Energy Technology Data Exchange (ETDEWEB)

    Mouradian, E. M.

    1983-12-31

    Thermal analyses for the preliminary design phase of the Receiver of the Carrizo Plains Solar Power Plant are presented. The sodium reference operating conditions (T/sub in/ = 610/sup 0/F, T/sub out/ = 1050/sup 0/F) have been considered. Included are: Nominal flux distribution on receiver panal, Energy input to tubes, Axial temperature distribution; sodium and tubes, Sodium flow distribution, Sodium pressure drop, orifice calculations, Temperature distribution in tube cut (R-0), Backface structure, and Nonuniform sodium outlet temperature. Transient conditions and panel front face heat losses are not considered. These are to be addressed in a subsequent design phase. Also to be considered later are the design conditions as variations from the nominal reference (operating) condition. An addendum, designated Appendix C, has been included describing panel heat losses, panel temperature distribution, and tube-manifold joint thermal model.

  20. Working fluid selection for the Organic Rankine Cycle (ORC) exhaust heat recovery of an internal combustion engine power plant

    Science.gov (United States)

    Douvartzides, S.; Karmalis, I.

    2016-11-01

    Organic Rankine cycle technology is capable to efficiently convert low-grade heat into useful mechanical power. In the present investigation such a cycle is used for the recovery of heat from the exhaust gases of a four stroke V18 MAN 51/60DF internal combustion engine power plant operating with natural gas. Design is focused on the selection of the appropriate working fluid of the Rankine cycle in terms of thermodynamic, environmental and safety criteria. 37 candidate fluids have been considered and all Rankine cycles examined were subcritical. The thermodynamic analysis of all fluids has been comparatively undertaken and the effect of key operation conditions such as the evaporation pressure and the superheating temperature was taken into account. By appropriately selecting the working fluid and the Rankine cycle operation conditions the overall plant efficiency was improved by 5.52% and fuel consumption was reduced by 12.69%.

  1. Vascular plants of the Nevada Test Site and Central-Southern Nevada: ecologic and geographic distributions

    Energy Technology Data Exchange (ETDEWEB)

    Beatley, J.C.

    1976-01-01

    The physical environment of the Nevada Test Site and surrounding area is described with regard to physiography, geology, soils, and climate. A discussion of plant associations is given for the Mojave Desert, Transition Desert, and Great Basin Desert. The vegetation of disturbed sites is discussed with regard to introduced species as well as endangered and threatened species. Collections of vascular plants were made during 1959 to 1975. The plants, belonging to 1093 taxa and 98 families are listed together with information concerning ecologic and geographic distributions. Indexes to families, genera, and species are included. (HLW)

  2. Plant physiological models of heat, water and photoinhibition stress for climate change modelling and agricultural prediction

    Science.gov (United States)

    Nicolas, B.; Gilbert, M. E.; Paw U, K. T.

    2015-12-01

    Soil-Vegetation-Atmosphere Transfer (SVAT) models are based upon well understood steady state photosynthetic physiology - the Farquhar-von Caemmerer-Berry model (FvCB). However, representations of physiological stress and damage have not been successfully integrated into SVAT models. Generally, it has been assumed that plants will strive to conserve water at higher temperatures by reducing stomatal conductance or adjusting osmotic balance, until potentially damaging temperatures and the need for evaporative cooling become more important than water conservation. A key point is that damage is the result of combined stresses: drought leads to stomatal closure, less evaporative cooling, high leaf temperature, less photosynthetic dissipation of absorbed energy, all coupled with high light (photosynthetic photon flux density; PPFD). This leads to excess absorbed energy by Photosystem II (PSII) and results in photoinhibition and damage, neither are included in SVAT models. Current representations of photoinhibition are treated as a function of PPFD, not as a function of constrained photosynthesis under heat or water. Thus, it seems unlikely that current models can predict responses of vegetation to climate variability and change. We propose a dynamic model of damage to Rubisco and RuBP-regeneration that accounts, mechanistically, for the interactions between high temperature, light, and constrained photosynthesis under drought. Further, these predictions are illustrated by key experiments allowing model validation. We also integrated this new framework within the Advanced Canopy-Atmosphere-Soil Algorithm (ACASA). Preliminary results show that our approach can be used to predict reasonable photosynthetic dynamics. For instances, a leaf undergoing one day of drought stress will quickly decrease its maximum quantum yield of PSII (Fv/Fm), but it won't recover to unstressed levels for several days. Consequently, cumulative effect of photoinhibition on photosynthesis can cause

  3. Effect of volume loading on the Frank-Starling relation during reductions in central blood volume in heat-stressed humans.

    Science.gov (United States)

    Bundgaard-Nielsen, M; Wilson, T E; Seifert, T; Secher, N H; Crandall, C G

    2010-09-01

    During reductions in central blood volume while heat stressed, a greater decrease in stroke volume (SV) for a similar decrease in ventricular filling pressure, compared to normothermia, suggests that the heart is operating on a steeper portion of a Frank-Starling curve. If so, volume loading of heat-stressed individuals would shift the operating point to a flatter portion of the heat stress Frank-Starling curve thereby attenuating the reduction in SV during subsequent decreases in central blood volume. To investigate this hypothesis, right heart catheterization was performed in eight males from whom pulmonary capillary wedge pressure (PCWP), central venous pressure and SV (via thermodilution) were obtained while central blood volume was reduced via lower-body negative pressure (LBNP) during normothermia, whole-body heating (increase in blood temperature 1 degrees C), and during whole-body heating after intravascular volume expansion. Volume expansion was accomplished by administration of a combination of a synthetic colloid (HES 130/0.4, Voluven) and saline. Before LBNP, SV was not affected by heating (122 +/- 30 ml; mean +/- s.d.) compared to normothermia (110 +/- 20 ml; P = 0.06). However, subsequent volume loading increased SV to 143 +/- 29 ml (P = 0.003). LBNP provoked a larger decrease in SV relative to the decrease in PCWP during heating (8.6 +/- 1.9 ml mmHg(1)) compared to normothermia (4.5 +/- 3.0 ml mmHg(1), P = 0.02). After volume loading while heat stressed, the reduction in the SV to PCWP ratio during LBNP was comparable to that observed during normothermia (4.8 +/- 2.3 ml mmHg(1); P = 0.78). These data support the hypothesis that a Frank-Starling mechanism contributes to compromised blood pressure control during simulated haemorrhage in heat-stressed individuals, and extend those findings by showing that volume infusion corrects this deficit by shifting the operating point to a flatter portion of the heat stress Frank-Starling curve.

  4. RESPONSE OF RICE PLANTS TO HEAT STRESS DURING INITIATION OF PANICLE PRIMORDIA OR GRAIN-FILLING PHASES

    OpenAIRE

    2013-01-01

    Leaf photosynthesis, a major determinant for yield sustainability in rice, is greatly conditioned by high temperature stress during growth. The effect of short-term high temperatures on leaf photosynthesis, stomatal conductance, Fv/Fm, SPAD readings and yield characteristics was studied in two Colombian rice cultivars. Two genotypes, cv. Fedearroz 50 (F50) and cv. Fedearroz 733 (F733) were used in pot experiments with heat stress treatment (Plants were exposed to 40°C for two and half hours f...

  5. The Forest Energy Chain in Tuscany: Economic Feasibility and Environmental Effects of Two Types of Biomass District Heating Plant

    Directory of Open Access Journals (Sweden)

    Claudio Fagarazzi

    2014-09-01

    Full Text Available The purpose of this study was to examine two biomass district heating plants operating in Tuscany, with a specific focus on the ex-post evaluation of their economic and financial feasibility and of their environmental benefits. The former biomass district heating plant supplies only public users (Comunità Montana della Lunigiana, CML: administrative body that coordinates the municipalities located in mountain areas, the latter supplies both public and private users (Municipality of San Romano in Garfagnana. Ex-post investment analysis was performed to check both the consistency of results with the forecasts made in the stage of the project design and on the factors, which may have reduced or jeopardized the estimated economic performance of the investment (ex-ante assessment. The results of the study point out appreciable results only in the case of biomass district heating plants involving private users and fuelled by biomasses sourced from third parties. In this case, the factors that most influence ex-post results include the conditions of the woody biomass local market (market prices, the policies of energy selling prices to private users and the temporal dynamics of private users’ connection. To ensure the consistency of ex-post economic outcome with the expected results it is thus important to: (i have good knowledge of the woody local market; (ii define energy selling prices that should be cheap for private users but consistent with energy production costs and (iii constrain private users beforehand to prevent errors in the plant design and in the preliminary estimate of return on investment. Moreover, the results obtained during the monitoring activities could help in providing information on the effectiveness of the supporting measures adopted and also to orient future choices of policy makers and particularly designers, to identify the most efficient configuration of district heating organization for improving energy and

  6. Regional Climate Zone Modeling of a Commercial Absorption Heat Pump Hot Water Heater Part 1: Southern and South Central Climate Zones

    Energy Technology Data Exchange (ETDEWEB)

    Geoghegan, Patrick J [ORNL; Shen, Bo [ORNL; Keinath, Christopher M. [Stone Mountain Technologies, Inc., Johnson City; Garrabrant, Michael A. [Stone Mountain Technologies, Inc., Johnson City

    2016-01-01

    Commercial hot water heating accounts for approximately 0.78 Quads of primary energy use with 0.44 Quads of this amount from natural gas fired heaters. An ammonia-water based commercial absorption system, if fully deployed, could achieve a high level of savings, much higher than would be possible by conversion to the high efficiency nonheat-pump gas fired alternatives. In comparison with air source electric heat pumps, the absorption system is able to maintain higher coefficients of performance in colder climates. The ammonia-water system also has the advantage of zero Ozone Depletion Potential and low Global Warming Potential. A thermodynamic model of a single effect ammonia-water absorption system for commercial space and water heating was developed, and its performance was investigated for a range of ambient and return water temperatures. This allowed for the development of a performance map which was then used in a building energy modeling software. Modeling of two commercial water heating systems was performed; one using an absorption heat pump and another using a condensing gas storage system. The energy and financial savings were investigated for a range of locations and climate zones in the southern and south central United States. A follow up paper will analyze northern and north/central regions. Results showed that the system using an absorption heat pump offers significant savings.

  7. Heterologous expression of a plant small heat-shock protein enhances Escherichia coli viability under heat and cold stress.

    Science.gov (United States)

    Soto, A; Allona, I; Collada, C; Guevara, M A; Casado, R; Rodriguez-Cerezo, E; Aragoncillo, C; Gomez, L

    1999-06-01

    A small heat-shock protein (sHSP) that shows molecular chaperone activity in vitro was recently purified from mature chestnut (Castanea sativa) cotyledons. This protein, renamed here as CsHSP17. 5, belongs to cytosolic class I, as revealed by cDNA sequencing and immunoelectron microscopy. Recombinant CsHSP17.5 was overexpressed in Escherichia coli to study its possible function under stress conditions. Upon transfer from 37 degrees C to 50 degrees C, a temperature known to cause cell autolysis, those cells that accumulated CsHSP17.5 showed improved viability compared with control cultures. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of cell lysates suggested that such a protective effect in vivo is due to the ability of recombinant sHSP to maintain soluble cytosolic proteins in their native conformation, with little substrate specificity. To test the recent hypothesis that sHSPs may be involved in protection against cold stress, we also studied the viability of recombinant cells at 4 degrees C. Unlike the major heat-induced chaperone, GroEL/ES, the chestnut sHSP significantly enhanced cell survivability at this temperature. CsHSP17.5 thus represents an example of a HSP capable of protecting cells against both thermal extremes. Consistent with these findings, high-level induction of homologous transcripts was observed in vegetative tissues of chestnut plantlets exposed to either type of thermal stress but not salt stress.

  8. CO2 capture processes in power plants - Le captage du CO2 dans les centrales thermiques

    CERN Document Server

    Bouallou, Chakib

    2010-01-01

    This review is devoted to assess and compare various processes aiming at recover CO2 from power plants fed with natural gas (NGCC) and pulverized coal (PC). These processes are post combustion CO2 capture using chemical solvents, natural gas reforming for pre-combustion capture and oxy-fuel combustion with cryogenic recovery of CO2. These processes were evaluated to give some clues for choosing the best option for each type of power plant. The comparison of these various concepts suggests that, in the short and medium term, chemical absorption is the most interesting process for NGCC power plants. For CP power plants, oxy-combustion can be a very interesting option, as well as post-combustion capture by chemical solvents.

  9. Diversity and Growth Behaviour of Nepenthes (Pitcher Plants in Tanjung Puting National Park, Central Kalimantan Province

    Directory of Open Access Journals (Sweden)

    DODO

    2005-10-01

    Full Text Available Nepenthes is one of the popular genus of pitcher plants. Research on the biodiversity and growth beharviour of Nepenthes spp. in Tanjung Puting National Park was carried out. There were four species studied, namely: N. ampullaria, N. mirabilis N. rafflesiana, and N. x. hookeriana,. There were about 2096 individuals recorded in this study consisting of 1322 N. ampullaria, 1332 N. mirabilis, 141 N. rafflesiana, and 111 N. x. hookeriana. Variation of tendril positions occurred in 1 rosette plant and 3 climbing stems (mature plants of N. ampullaria, 2 rosettes and 9 mature N. mirabilis, 1 rosette and 4 mature N. rafflesiana, 2 rosettes and 2 mature N. x. hookeriana. Their habitats were also very specific. It was noted that 6 species of other plants were grown and associated with the Nepenthes spp.

  10. 2010 Pacific Gas and Electric Diablo Canyon Power Plant (DCPP): Diablo Canyon, CA Central Coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Diablo Canyon Power Plant (DCPP) LiDAR and Imagery datasets are comprised of three separate LiDAR surveys: Diablo Canyon (2010), Diablo Canyon (2010), and San...

  11. 2011 Pacific Gas and Electric Diablo Canyon Power Plant (DCPP): Los Osos, CA Central Coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Diablo Canyon Power Plant (DCPP) LiDAR and Imagery datasets are comprised of three separate LiDAR surveys: Diablo Canyon (2010), Los Osos (2011), and San Simeon...

  12. 2013 Pacific Gas and Electric Diablo Canyon Power Plant (DCPP): San Simeon, CA Central Coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Diablo Canyon Power Plant (DCPP) LiDAR and Imagery datasets are comprised of three separate LiDAR surveys: Diablo Canyon (2010), Los Osos (2011), and San Simeon...

  13. Analytical and experimental stiffness estimation of heat pipe supporter for nuclear power plant through a homogenization process

    Directory of Open Access Journals (Sweden)

    Sang-Young Kim

    2015-07-01

    Full Text Available This article aims to study the in-plane stiffness estimation of heat pipe supporter (a large lattice structure using experimental and numerical methods. The in-plane stiffness of heat pipe supporter for nuclear power plant is very important because of the safety against natural disasters, such as seismic load or tsunami, and has to be evaluated because it greatly affects the durability of the heat exchanger. However, the modeling process of the whole lattice structure for finite element analysis increases resources needed caused by too many nodes and elements. In this study, the mechanical properties of large lattice structures are determined by a unit cell finite element analysis. The mechanical behavior of a large lattice structure has been estimated by finite element analysis through a homogenization process for reducing analysis time and efforts. The finite element analysis results have been verified and show a good agreement with the experimental results.

  14. Combustion testing and heat recovery study: Frank E. Van Lare Wastewater Treatment Plant, Monroe County. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-01-01

    The objectives of the study were to record and analyze sludge management operations data and sludge incinerator combustion data; ascertain instrumentation and control needs; calculate heat balances for the incineration system; and determine the feasibility of different waste-heat recovery technologies for the Frank E. Van Lare (FEV) Wastewater Treatment Plant. As an integral part of this study, current and pending federal and state regulations were evaluated to establish their impact on furnace operation and subsequent heat recovery. Of significance is the effect of the recently promulgated Federal 40 CFR Part 503 regulations on the FEV facility. Part 503 regulations were signed into law in November 1992, and, with some exceptions, affected facilities must be in compliance by February 19, 1994. Those facilities requiring modifications or upgrades to their incineration or air pollution control equipment to meet Part 503 regulations must be in compliance by February 19, 1995.

  15. The contents of uranium and thorium in the dominating kinds of plants of the Central Caucasus

    Directory of Open Access Journals (Sweden)

    T. A. Asvarova

    2008-01-01

    Full Text Available The result of this work have shown that the difference of contents uranium and thorium of various plants of Great Caucasus dependents views plants, on various types rock, type of soils and physicalchemicalproperties of soil. The maximum concentration of uranium and thorium are registered in Saxifraga mochata, S. Dinikii, S. exarata, S. carinata, and the minimum concentration is in Veratrum Lobelianum.

  16. Nuclear power plants making a comeback in Japan; El retorno de la centrales nucleares en Japon

    Energy Technology Data Exchange (ETDEWEB)

    Torralbo, J. R.

    2016-08-01

    We reproduce in this magazine the interesting article published by the president of the SNE in issue 46 of Cuadernos de Energia in October 2015, which describes the events that have taken place since the March 11, 2011 earthquake in Japan, the largest in its history, and the subsequent tsunami, which affected the Fukushima power plant, as well as the measures implemented since then and how some of this country nuclear power plants are being started up again. (Author)

  17. Unifying model of shoot gravitropism reveals proprioception as a central feature of posture control in plants

    DEFF Research Database (Denmark)

    Bastien, Renaud; Bohr, Tomas; Moulia, Bruno

    2012-01-01

    Gravitropism, the slow reorientation of plant growth in response to gravity, is a key determinant of the form and posture of land plants. Shoot gravitropism is triggered when statocysts sense the local angle of the growing organ relative to the gravitational field. Lateral transport of the hormone...... is thus as important as gravisensing in gravitropic control, and the B ratio can be measured as phenotype in genetic studies....

  18. Endangered plant species of the Nevada Test Site, Ash Meadows, and Central-Southern Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Beatley, J.C.

    1977-02-01

    A total of 15 vascular plant taxa, currently appearing on the Endangered Species list, occur in southern Nye County, Nevada, and/or adjacent Inyo County, California. It is the purpose of this report to record in detail the locations of the plant collections upon which the distributions are based, and other information relevant to their status as Endangered Species, and to recommend the areas to be designated critical habitats.

  19. The (safety-related) heat exchangers aging management guideline for commercial nuclear power plants, and developments since 1994

    Energy Technology Data Exchange (ETDEWEB)

    Clauss, J.M.

    1998-08-01

    The US Department of Energy (DOE), in cooperation with the Electric Power Research Institute (EPRI) and US nuclear power plant utilities, is preparing a series of aging management guidelines (AMGs) for commodity types of components (e.g., heat exchangers, electrical cable and terminations, pumps). Commodities are included in this series based on their importance to continued nuclear plant operation and license renewal. The AMGs contain a detailed summary of operating history, stressors, aging mechanisms, and various types of maintenance and surveillance practices that can be combined to create an effective aging management program. Each AMG is intended for use by the systems engineers and plant maintenance staff (i.e., an AMG is intended to be a hands-on technical document rather than a licensing document). The heat exchangers AMG, published in June 1994, includes the following information of interest to nondestructive examination (NDE) personnel: aging mechanisms determined to be non-significant for all applications; aging mechanisms determined to be significant for some applications; effective conventional programs for managing aging; and effective unconventional programs for managing aging. Since the AMG on heat exchangers was published four years ago, a brief review has been conducted to identify emerging regulatory issues, if any. The results of this review and lessons learned from the collective set of AMGs are presented.

  20. Influence of Tunisian aromatic plants on the prevention of oxidation in soybean oil under heating and frying conditions.

    Science.gov (United States)

    Saoudi, Salma; Chammem, Nadia; Sifaoui, Ines; Bouassida-Beji, Maha; Jiménez, Ignacio A; Bazzocchi, Isabel L; Silva, Sandra Diniz; Hamdi, Moktar; Bronze, Maria Rosário

    2016-12-01

    The aim of this study was to improve the oxidative stability of soybean oil by using aromatic plants. Soybean oil flavored with rosemary (ROS) and soybean oil flavored with thyme (THY) were subjected to heating for 24h at 180°C. The samples were analyzed every 6h for their total polar compounds, anisidine values, oxidative stability and polyphenols content. The tocopherols content was determined and volatile compounds were also analyzed. After 24h of heating, the incorporation of these plants using a maceration process reduced the polar compounds by 69% and 71% respectively, in ROS and THY compared to the control. Until 6h of heating, the ROS kept the greatest oxidative stability. The use of the two extracts preserves approximately 50% of the total tocopherols content until 18h for the rosemary and 24h for the thyme flavored oils. Volatile compounds known for their antioxidant activity were also detected in the formulated oils. Aromatic plants added to the soybean oil improved the overall acceptability of potato crisps (p<0.05) until the fifteenth frying.

  1. Electrochemical techniques application in corrosion problems of fossil power plants; Aplicacion de tecnicas electroquimicas en problemas de corrosion en centrales termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Cano Castillo, Ulises; Garcia Ochoa, Esteban Miguel; Martinez Villafane, Alberto; Mariaca Rodriguez, Liboria; Malo Tamayo, Jose Maria; Uruchurtu Chavarin, Jorge [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1990-12-31

    Some aspects of the electrochemical techniques employed to evaluate the corrosion at low temperature in fossil power plants are commented, as well as the results obtained with the application of them in three power plants of this type. [Espanol] Se comentan algunos aspectos de tecnicas electroquimicas utilizadas para evaluar la corrosion en baja temperatura en centrales termoelectricas, asi como los resultados de la aplicacion de las mismas en tres centrales de este tipo.

  2. Leaf-litter microfungal community on poor fen plant debris in Torfy Lake area (Central Poland

    Directory of Open Access Journals (Sweden)

    Mateusz Wilk

    2014-06-01

    Full Text Available The purpose of this study was to initially evaluate the species diversity of microfungi growing on litter of 15 plant species occurring on the poor fen and neighbouring area of the Torfy Lake, Masovian voivodeship, Poland. The lake is located near the planned road investment (construction of the Warsaw southern express ring road S2. The place is biologically valuable as there are rare plant communities from Rhynchosporion albae alliance protected under the Habitats Directive adopted by the European Union. On the examined plant debris 73 taxa of fungi were recorded (3 basidiomycetes, 13 ascomycetes, 2 zygomycetes, 43 anamorphic ascomycetes, 12 unidentified. Two of them, Dicranidion sp. and Wentiomyces sp. are presented here as new to Poland. Among the plant species examined, the litter of Rhododendron tomentosum harbored the highest number of fungal taxa (16. The highest percents of substrate-specific microfungi (i.e. recorded only on one plant species was noted on R. tomentosum (81.3 %, and Pteridium aquilinum (75%. It is emphasized that the lake area should be protected not only because of rare plant community but also because of the uniqueness and diversity of mycobiota.

  3. Response of rice plants to heat stress during initiation of panicle primordia or grain-filling phases

    Directory of Open Access Journals (Sweden)

    Hermann Restrepo-Diaz

    2013-08-01

    Full Text Available Leaf photosynthesis, a major determinant for yield sustainability in rice, is greatly conditioned by high temperature stress during growth. The effect of short-term high temperatures on leaf photosynthesis, stomatal conductance, Fv/Fm, SPAD readings and yield characteristics was studied in two Colombian rice cultivars. Two genotypes, cv. Fedearroz 50 (F50 and cv. Fedearroz 733 (F733 were used in pot experiments with heat stress treatment (Plants were exposed to 40°C for two and half hours for five consecutive days and natural temperature (control treatment. Heat treatments were carried out at the initiation of panicle primordial (IP or grain-filling (GF phases. The results showed that short-term high temperature stress produced a reduction on the photosynthesis rate in both cultivars either IP or GF phases. Similar trends were found on stomatal conductance in all cases due to high temperatures. Although Fv/Fm and SPAD readings were not affected by high temperatures, these variables diminished significantly among phenological phases. 'F733' rice plants showed higher number spikelet sterility due to heat stress treatments. These results seem to indicate that heat-tolerant cultivars of rice is associated with high levels of photosynthesis rate in leaves.

  4. Development of Molten-Salt Heat Transfer Fluid Technology for Parabolic Trough Solar Power Plants - Public Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Grogan, Dylan C. P.

    2013-08-15

    Executive Summary This Final Report for the "Development of Molten-Salt Heat Transfer Fluid (HTF) Technology for Parabolic Trough Solar Power Plants” describes the overall project accomplishments, results and conclusions. Phase 1 analyzed the feasibility, cost and performance of a parabolic trough solar power plant with a molten salt heat transfer fluid (HTF); researched and/or developed feasible component options, detailed cost estimates and workable operating procedures; and developed hourly performance models. As a result, a molten salt plant with 6 hours of storage was shown to reduce Thermal Energy Storage (TES) cost by 43.2%, solar field cost by 14.8%, and levelized cost of energy (LCOE) by 9.8% - 14.5% relative to a similar state-of-the-art baseline plant. The LCOE savings range met the project’s Go/No Go criteria of 10% LCOE reduction. Another primary focus of Phase 1 and 2 was risk mitigation. The large risk areas associated with a molten salt parabolic trough plant were addressed in both Phases, such as; HTF freeze prevention and recovery, collector components and piping connections, and complex component interactions. Phase 2 analyzed in more detail the technical and economic feasibility of a 140 MWe,gross molten-salt CSP plant with 6 hours of TES. Phase 2 accomplishments included developing technical solutions to the above mentioned risk areas, such as freeze protection/recovery, corrosion effects of applicable molten salts, collector design improvements for molten salt, and developing plant operating strategies for maximized plant performance and freeze risk mitigation. Phase 2 accomplishments also included developing and thoroughly analyzing a molten salt, Parabolic Trough power plant performance model, in order to achieve the project cost and performance targets. The plant performance model and an extensive basic Engineering, Procurement, and Construction (EPC) quote were used to calculate a real levelized cost of energy (LCOE) of 11.50

  5. Computer Security for Commercial Nuclear Power Plants - Literature Review for Korea Hydro Nuclear Power Central Research Institute

    Energy Technology Data Exchange (ETDEWEB)

    Duran, Felicia Angelica [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Security Systems Analysis Dept.; Waymire, Russell L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Security Systems Analysis Dept.

    2013-10-01

    Sandia National Laboratories (SNL) is providing training and consultation activities on security planning and design for the Korea Hydro and Nuclear Power Central Research Institute (KHNPCRI). As part of this effort, SNL performed a literature review on computer security requirements, guidance and best practices that are applicable to an advanced nuclear power plant. This report documents the review of reports generated by SNL and other organizations [U.S. Nuclear Regulatory Commission, Nuclear Energy Institute, and International Atomic Energy Agency] related to protection of information technology resources, primarily digital controls and computer resources and their data networks. Copies of the key documents have also been provided to KHNP-CRI.

  6. [The primary role of central region of HC-pro of potato Y potyvirus in synergism of plant viruses].

    Science.gov (United States)

    Lu, R F; Li, W M; Wang, H Y; Guo, M; Peng, X X

    2001-05-01

    Five deleted mutants of HC-Pro gene of Chinese isolate of potato Y potyvirus (PVY-C) were obtained by PCR mutation, and their plant expression vectors were constructed. They were transformed into tobacco K326 (Nicotina tabacum cv. K326) mediated by Agrobacterium. PCR and Southern blot analysis revealed that PVY-C HC-Pro gene and its deleted mutants were integrated into tobacco genome, and Western blot analysis showed that they were all expressed in transgenic tobacco plants. Furthermore, infection test demonstrated that the central region of PVY-C HC-Pro can mediate synergism of PVY-C/cucumber mosaic cucumovirus (CMV) and PVY-C/potato X potexvirus (PVX), identifying that it is functional domain in synergism.

  7. Evaluation of cable ageing in Nuclear Power Plants; Evaluacion del envejecimiento de cables en centrales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Vergara, T. [Empresarios Agrupados, A. I. E. Madrid (Spain); Alonso Chicote, J. [TECNATOM, S. A. (Spain); Burnay, S. [AEA Technology (UK)

    2000-07-01

    The majority of power, control and instrumentation cables in nuclear power plants use polymers as their basic material for insulation and jacket. In many cases, these cables form part of safety-related circuits and should therefore be capable of operating correctly under both normal and accident conditions. Since polymeric materials are degraded by the long term action of the radiation and thermal environments found in the plant, it is important to be able to establish the cable condition during the plant lifetime. Nowadays there are a number of different methods to evaluate the remaining lifetime of cables. In the case of new plants, or new cables in old plants, accelerated ageing tests and predictive models can be used to establish the behaviour of the cable materials under operating conditions. There are verified techniques and considerable experience in the definition of predictive models. This type of approach is best carried out during the commissioning stage or in the early stages of operation. In older plants, particularly where there is a wide range of cable types in use, it is more appropriate to use condition monitoring methods to establish the state of degradation of cables in-plant. Over the last 10 years there have been considerable developments in methods for condition monitoring of cables and a tool-box of practical techniques are now available. There is no single technique which is suitable for all cable materials but the range of methods covers nearly all of the types currently in use, at present, the most established methods are the indented, thermal analysis (OIT, OITP and TGA) and dielectric loss measurements, All of these are either non-destructive methods or require only micro-samples of material. (Author) 15 refs.

  8. Using waste heat for cooling with compact resorption plants; Kompakte Resorptionsanlagen zum Kuehlen mit Abwaerme

    Energy Technology Data Exchange (ETDEWEB)

    Weimer, Thomas [Makatec GmbH, Bondorf (Germany); Helle, Kirsten [Institut fuer Energie- und Umwelttechnik (IUTA) e.V. Energy Conversion and Energy Storage, Duisburg (Germany)

    2012-03-15

    Cooling technologies gain an increasing importance in the industrialized world. Ammonia based absorption chillers can be employed for air conditioning and refrigeration, using waste heat as driving force. With using the resorption technology for ammonia based absorption chillers gas cleaning is needless. Resorption systems consist of two solvent cycles exchanging refrigerant, both with absorber, desorber and solvent heat exchanger. Plate heat exchangers or new membrane contactors used as desorber and absorber lead to compact resorption chillers. (orig.)

  9. Performance Improvement of Combined Cycle Power Plant Based on the Optimization of the Bottom Cycle and Heat Recuperation

    Institute of Scientific and Technical Information of China (English)

    Wenguo XIANG; Yingying CHEN

    2007-01-01

    Many F class gas turbine combined cycle (GTCC) power plants are built in China at present because of less emission and high efficiency. It is of great interest to investigate the efficiency improvement of GTCC plant. A combined cycle with three-pressure reheat heat recovery steam generator (HRSG) is selected for study in this paper.In order to maximize the GTCC efficiency, the optimization of the HRSG operating parameters is performed. The operating parameters are determined by means of a thermodynamic analysis, i.e. the minimization of exergy losses. The influence of HRSG inlet gas temperature on the steam bottoming cycle efficiency is discussed. The result shows that increasing the HRSG inlet temperature has less improvement to steam cycle efficiency when it is over 590℃. Partial gas to gas recuperation in the topping cycle is studied. Joining HRSG optimization with the use of gas to gas heat recuperation, the combined plant efficiency can rise up to 59.05% at base load. In addition,the part load performance of the GTCC power plant gets much better. The efficiency is increased by 2.11% at 75% load and by 4.17% at 50% load.

  10. Central heating: package boilers

    Energy Technology Data Exchange (ETDEWEB)

    Farahan, E.

    1977-05-01

    Performance and cost data for electrical and fossil-fired package boilers currently available from manufacturers are provided. Performance characteristics investigated include: unit efficiency, rated capacity, and average expected lifetime of units. Costs are tabulated for equipment and installation of various package boilers. The information supplied in this report will simplify the process of selecting package boilers required for industrial, commercial, and residential applications.

  11. Industrial applications study. Volume IV. Industrial plant surveys. Final report. [Waste heat recovery and utilization

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Harry L.; Hamel, Bernard B.; Karamchetty, Som; Steigelmann, William H.; Gajanana, Birur C.; Agarwal, Anil P.; Klock, Lawrence M.; Henderson, James M.; Calobrisi, Gary; Hedman, Bruce A.; Koluch, Michael; Biancardi, Frank; Bass, Robert; Landerman, Abraham; Peters, George; Limaye, Dilip; Price, Jeffrey; Farr, Janet

    1977-01-01

    An initial evaluation of the waste heat recovery and utilization potential in the manufacturing portion of the industrial sector is presented. The scope of this initial phase addressed the feasibility of obtaining in-depth energy information in the industrial sector. Within this phase, the methodology and approaches for data gathering and assessment were established. Using these approaches, energy use and waste heat profiles were developed at the 2-digit level; with this data, waste heat utilization technologies were evaluated. This study represents an important first step in the evaluation of waste heat recovery potential.

  12. Heat-shock protein 70 from plant biofactories of recombinant antigens activate multiepitope-targeted immune responses.

    Science.gov (United States)

    Buriani, Giampaolo; Mancini, Camillo; Benvenuto, Eugenio; Baschieri, Selene

    2012-04-01

    Although a physiological role of heat-shock proteins (HSP) in antigen presentation and immune response activation has not been directly demonstrated, their use as vaccine components is under clinical trial. We have previously demonstrated that the structure of plant-derived HSP70 (pHSP70) can be superimposed to the mammalian homologue and similarly to the mammalian counterpart, pHSP70-polypeptide complexes can activate the immune system. It is here shown that pHSP70 purified from plant tissues transiently expressing the influenza virus nucleoprotein are able to induce both the activation of major histocompatibility complex class I-restricted polyclonal T-cell responses and antibody production in mice of different haplotypes without the need of adjuvant co-delivery. These results indicate that pHSP70 derived from plants producing recombinant antigens may be used to formulate multiepitope vaccines.

  13. Power plant waste heat utilization in aquaculture. Volume III. Final report, 1 November 1976-1 November 1979

    Energy Technology Data Exchange (ETDEWEB)

    Farmanfarmaian, A.

    1980-03-01

    This report is part of a three year research study on the constructive use of electric generating station waste heat in cooling water effluents for fish production. It describes procedures and methods for the commercial culture of the giant fresh water shrimp, Macrobrachium rosenbergii, and the rainbow trout, Salmo gairdneri, in the thermal discharge water of the Mercer Power Plant in Trenton, New Jersey. Discharge water from this plant was used in a preliminary assessment of the survival, growth, and food conversion ratio of these species. It was shown that acute or chronic exposure to power plant intake and discharge water; discharge with or without coal particles; and discharge with or without slurry overflow mix does not significantly affect metabolism, short-term survival, growth, or conversion efficiency of shrimp or trout.

  14. Central Receiver Solar Thermal Power System, Phase 1. CDRL Item 2. Pilot Plant preliminary design report. Volume III, Book 1. Collector subsystem

    Energy Technology Data Exchange (ETDEWEB)

    Hallet, Jr., R. W.; Gervais, R. L.

    1977-10-01

    The central receiver system consists of a field of heliostats, a central receiver, a thermal storage unit, an electrical power generation system, and balance of plant. This volume discusses the collector field geometry, requirements and configuration. The development of the collector system and subsystems are discussed and the selection rationale outlined. System safety and availability are covered. Finally, the plans for collector portion of the central receiver system are reviewed.

  15. Ground acceleration in a nuclear power plant; Aceleracion del suelo en una central nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Pena G, P.; Balcazar, M.; Vega R, E., E-mail: pablo.pena@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2015-09-15

    A methodology that adopts the recommendations of international organizations for determining the ground acceleration at a nuclear power plant is outlined. Systematic presented here emphasizes the type of geological, geophysical and geotechnical studies in different areas of influence, culminating in assessments of Design Basis earthquake and the earthquake Operating Base. The methodology indicates that in regional areas where the site of the nuclear power plant is located, failures are identified in geological structures, and seismic histories of the region are documented. In the area of detail geophysical tools to generate effects to determine subsurface propagation velocities and spectra of the induced seismic waves are used. The mechanical analysis of drill cores allows estimating the efforts that generate and earthquake postulate. Studies show that the magnitude of the Fukushima earthquake, did not affect the integrity of nuclear power plants due to the rocky settlement found. (Author)

  16. Exergoeconomic performance optimization of an endoreversible intercooled regenerated Brayton cogeneration plant. Part 2: Heat conductance allocation and pressure ratio optimization

    Directory of Open Access Journals (Sweden)

    Bo Yang, Lingen Chen, Fengrui Sun

    2011-03-01

    Full Text Available Finite time exergoeconomic performance of an endoreversible intercooled regenerative Brayton cogeneration plant is optimized based on the model which is established using finite time thermodynamic in Part 1 of this paper. It is found that the optimal heat conductance allocation of the regenerator is zero. When the total pressure ratio and the heat conductance allocation of the regenerator are fixed, it is shown that there exist an optimal intercooling pressure ratio, and a group of optimal heat conductance allocations among the hot-, cold- and consumer-side heat exchangers and the intercooler, which correspond to a maximum dimensionless profit rate. When the total pressure ratio is variable, there exists an optimal total pressure ratio which corresponds to a double-maximum dimensionless profit rate, and the corresponding exergetic efficiency is obtained. The effects of the total heat exchanger conductance, price ratios and the consumer-side temperature on the double-maximum dimensionless profit rate and the corresponding exergetic efficiency are discussed. It is found that there exists an optimal consumer-side temperature which corresponds to a thrice-maximum dimensionless profit rate.

  17. Diurnal variability of heat fluxes and heat content at a few locations off central east coast of India during April 1989

    Digital Repository Service at National Institute of Oceanography (India)

    Sadhuram, Y.; Rao, B.P.; Rao, V.S.; Rao, T.V.N.

    Diurnal variability of surface wind speed, net heat exchange, sea surface temperature, vertical thermal structure and heat content at three locations, viz., station A (17 degrees 59'N, 83 degrees 53.9'E), station B (17 degrees 00'N, 82 degrees 32...

  18. Heat transfer equipment performance diagnosis of auxiliary systems in electric power stations; Diagnostico de comportamiento de equipo de transferencia de calor de sistemas auxiliares de centrales termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Esparza Gutierrez, Rogelio [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1990-12-31

    In this article the methodology followed to diagnose the performance of the equipment where heat is transferred from the feed water, condensate and circulation water systems in fossil power plants (FPP). The data collection is made with the unit in normal operation, using local instrumentation without taking the equipment out of service for its installation. The equipment diagnosis is made through the analysis of the collected data in actual operation and the design data; for this purpose a thermal balance of the interested systems is performed to obtain all the conditions an operation data. Later on the performance indicative parameters (PIP) of actual operation and design are calculated and compared one against the other. Such a comparison reveals the performance deterioration and the possible equipment faults. The data obtained and the supplementary information are stored in a data base whose objective is that Comision Federal de Electricidad has on hand a prompt access to them in order to control the performance, compare them among similar units and power stations, and inclusively verify possible recurrent causes of low availability in the referred systems. [Espanol] En este articulo se presenta la metodologia seguida para diagnosticar el comportamiento de equipos en los que se transfiere calor de los sistemas de agua de alimentacion, condensado y circulacion de las centrales termoelectricas (CTE). La toma de datos se realiza con la unidad en operacion normal, utilizando instrumentacion local sin necesidad de sacar de servicio a los equipos para su instalacion, ya que se ocupan los mismos puntos para instrumentos con que cuentan por diseno. El diagnostico de los equipos se realiza mediante el analisis de los datos recopilados, tanto de operacion real como de diseno; para ello, se efectua un balance termico de los sistemas de interes para obtener todas las condiciones y los datos de operacion. Posteriormente, se calculan los parametros indicativos de

  19. Thermal gain of CHP steam generator plants and heat supply systems

    Science.gov (United States)

    Ziganshina, S. K.; Kudinov, A. A.

    2016-08-01

    Heating calculation of the surface condensate heat recovery unit (HRU) installed behind the BKZ-420-140 NGM boiler resulting in determination of HRU heat output according to fire gas value parameters at the heat recovery unit inlet and its outlet, heated water quantity, combustion efficiency per boiler as a result of installation of HRU, and steam condensate discharge from combustion products at its cooling below condensing point and HRU heat exchange area has been performed. Inspection results of Samara CHP BKZ-420-140 NGM power boilers and field tests of the surface condensate heat recovery unit (HRU) made on the bimetal calorifier base KCk-4-11 (KSk-4-11) installed behind station no. 2 Ulyanovsk CHP-3 DE-10-14 GM boiler were the basis of calculation. Integration of the surface condensation heat recovery unit behind a steam boiler rendered it possible to increase combustion efficiency and simultaneously decrease nitrogen oxide content in exit gases. Influence of the blowing air moisture content, the excess-air coefficient in exit gases, and exit gases temperature at the HRU outlet on steam condensate amount discharge from combustion products at its cooling below condensing point has been analyzed. The steam condensate from HRU gases is offered as heat system make-up water after degasification. The cost-effectiveness analysis of HRU installation behind the Samara CHP BKZ-420-140 NGM steam boiler with consideration of heat energy and chemically purified water economy has been performed. Calculation data for boilers with different heat output has been generalized.

  20. Conceptual design of advanced central receiver power systems sodium-cooled receiver concept. Volume 4. Commercial and pilot plant cost data. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-03-01

    This volume of the advanced central receiver final report presents the cost data using the cost breakdown structure identified in the preliminary specification. Cost summaries are presented in the following sections for the 100-MWe and 281-MWe commercial plant and a 10-MWe pilot plant. Cost substantiation data for this volume are presented in the appendices. Other cost summary data include Nth plant data for the 100-MWe and 281-MWe commercial plants, and a summary for the alternative concept air-rock storage system. The main description of the plant costing technique occurs as part of Section II for the 100-MWe baseline concept.

  1. Energy efficiency comparison of a centralized and a multi-agent market based heating system in a field test

    NARCIS (Netherlands)

    Pruissen, O.P. van; Togt, A. van der; Werkman, E.

    2014-01-01

    For the built environment it is envisaged that in the near future the total annual heat demand could be covered by renewable sources generated within the built environment. More and more devices, such as heat pumps and solar collectors will enable a sustainable and distributed generation of heat. Ce

  2. Final Technical Report: Using Solid Particles as Heat Transfer Fluid for use in Concentrating Solar Power (CSP) Plants

    Energy Technology Data Exchange (ETDEWEB)

    Lattanzi, Aaron [Univ. of Colorado, Boulder, CO (United States); Hrenya, Christine [Univ. of Colorado, Boulder, CO (United States)

    2016-03-31

    In today’s industrial economy, energy consumption has never been higher. Over the last 15 years the US alone has consumed an average of nearly 100 quadrillion BTUs per year [21]. A need for clean and renewable energy sources has become quite apparent. The SunShot Initiative is an ambitious effort taken on by the United States Department of Energy that targets the development of solar energy that is cost-competitive with other methods for generating electricity. Specifically, this work is concerned with the development of concentrating solar power plants (CSPs) with granular media as the heat transfer fluid (HTF) from the solar receiver. Unfortunately, the prediction of heat transfer in multiphase flows is not well understood. For this reason, our aim is to fundamentally advance the understanding of multiphase heat transfer, particularly in gas-solid flows, while providing quantitative input for the design of a near black body receiver (NBB) that uses solid grains (like sand) as the HTF. Over the course of this three-year project, a wide variety of contributions have been made to advance the state-of-the art description for non-radiative heat transfer in dense, gas-solid systems. Comparisons between a state-of-the-art continuum heat transfer model and discrete element method (DEM) simulations have been drawn. The results of these comparisons brought to light the limitations of the continuum model due to inherent assumptions in its derivation. A new continuum model was then developed for heat transfer at a solid boundary by rigorously accounting for the most dominant non-radiative heat transfer mechanism (particle-fluid-wall conduction). The new model is shown to be in excellent agreement with DEM data and captures the dependence of heat transfer on particle size, a dependency that previous continuum models were not capable of. DEM and the new continuum model were then employed to model heat transfer in a variety of receiver geometries. The results provided crucial

  3. Human psychophysics and rodent spinal neurones exhibit peripheral and central mechanisms of inflammatory pain in the UVB and UVB heat rekindling models.

    Science.gov (United States)

    O'Neill, Jessica; Sikandar, Shafaq; McMahon, Stephen B; Dickenson, Anthony H

    2015-09-01

    Translational research is key to bridging the gaps between preclinical findings and the patients, and a translational model of inflammatory pain will ideally induce both peripheral and central sensitisation, more effectively mimicking clinical pathophysiology in some chronic inflammatory conditions. We conducted a parallel investigation of two models of inflammatory pain, using ultraviolet B (UVB) irradiation alone and UVB irradiation with heat rekindling. We used rodent electrophysiology and human quantitative sensory testing to characterise nociceptive processing in the peripheral and central nervous systems in both models. In both species, UVB irradiation produces peripheral sensitisation measured as augmented evoked activity of rat dorsal horn neurones and increased perceptual responses of human subjects to mechanical and thermal stimuli. In both species, UVB with heat rekindling produces central sensitisation. UVB irradiation alone and UVB with heat rekindling are translational models of inflammation that produce peripheral and central sensitisation, respectively. The predictive value of laboratory models for human pain processing is crucial for improving translational research. The discrepancy between peripheral and central mechanisms of pain is an important consideration for drug targets, and here we describe two models of inflammatory pain that involve ultraviolet B (UVB) irradiation, which can employ peripheral and central sensitisation to produce mechanical and thermal hyperalgesia in rats and humans. We use electrophysiology in rats to measure the mechanically- and thermally-evoked activity of rat spinal neurones and quantitative sensory testing to assess human psychophysical responses to mechanical and thermal stimulation in a model of UVB irradiation and in a model of UVB irradiation with heat rekindling. Our results demonstrate peripheral sensitisation in both species driven by UVB irradiation, with a clear mechanical and thermal hypersensitivity of

  4. Atmospheric pollution in thermal power plants; Contaminacion atmosferica en centrales termicas convencionales

    Energy Technology Data Exchange (ETDEWEB)

    Aguirre Diaz, A.

    1997-04-01

    The author presents the atmospheric pollution by fossil-fuel power plants. The state of the art is developed in 4 chapters: Legislation, Sulfur dioxide: reduction of SO{sub 2}, nitrogen oxides: reduction of emissions, particulates: reduction of particulates and new technologies. (Author)

  5. PLANT REMAINS FROM ASIKLI-HOYUK, A PRE-POTTERY NEOLITHIC SITE IN CENTRAL ANATOLIA

    NARCIS (Netherlands)

    VANZEIST, W; DEROLLER, GJ

    1995-01-01

    Cereal crop plants at Asikli Hayuk included einkorn wheat (Triticum monococcum), emmer wheat (T. dicoccum), free-threshing wheat (T. cf. durum), hulled two-rowed barley (Hordeum distichum) and naked barley (H. vulgare var. nudum). As for pulses, bitter vetch (Vicia ervilia), lentil (Lens culinaris)

  6. Refueling outage services in Spanish Nuclear Power Plants; Servicios en recargas de centrales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Landete, J. L.; Soto, M.; Nunuez, A.

    2007-07-01

    DOMINGUIS Group, through its 75 years of business development, has positioned as the Spanish leader Group in Services for the Nuclear Energy and Petrochemical Sectors. In this article, we present the most significant services summary that, through the companies that constitute DOMINGUIS Group, we have developed in Refueling Outage in Spanish Nuclear Power Plants. (Author)

  7. Central Cell-Derived Peptides Regulate Early Embryo Patterning in Flowering Plants

    NARCIS (Netherlands)

    Costa, L.M.; Marshall, E.; Tesfaye, M.; Silverstein, K.A.T.; Mori, M.; Umetsu, Y.; Otterbach, S.L.; Papareddy, R.; Dickinson, H.G.; Boutilier, K.A.; VandenBosch, K.A.; Ohki, S.; Gutierrez-Marcos, J.F.

    2014-01-01

    Plant embryogenesis initiates with the establishment of an apical-basal axis; however, the molecular mechanisms accompanying this early event remain unclear. Here, we show that a small cysteine-rich peptide family is required for formation of the zygotic basal cell lineage and proembryo patterning i

  8. Aliens in Transylvania: risk maps of invasive alien plant species in Central Romania

    Directory of Open Access Journals (Sweden)

    Heike Zimmermann

    2015-01-01

    Full Text Available Using the MAXENT algorithm, we developed risk maps for eight invasive plant species in southern Transylvania, Romania, a region undergoing drastic land-use changes. Our findings show that invasion risk increased with landscape heterogeneity. Roads and agricultural areas were most prone to invasion, whereas forests were least at risk.

  9. Fluvial adjustments to soil erosion and plant cover changes in the Central Spanish Pyrenees

    NARCIS (Netherlands)

    Beguería, S.; López-Moreno, J.I.; Gómez-Villar, A.; Rubio, V.; Lana-Renault, N.; García-Ruiz, J.M.

    2007-01-01

    Until the middle of the 20th Century, Pyrenean rivers were characterized by braided channels, unstable sedimentary structures and an almost complete lack of plant cover in the alluvial plain, due to the high sediment yield in hillslopes and the occurrence of frequent and intense flooding. This was p

  10. Economic Analysis of Floricultural Plants Production in Kwara State, North Central Nigeria

    Directory of Open Access Journals (Sweden)

    Muhammad-Lawal, A.

    2012-09-01

    Full Text Available In spite of the substantial contribution of floriculture to the Nigerian economy, there is still a low level of awareness on the potential of the horticultural subsector of the Nigerian agricultural sector to generate employment and reduce poverty. This study therefore carried out an assessment of the economics of floricultural plants production in Kwara State, Nigeria. The study specifically estimated the returns to farmer’s labour and management. It also assessed the determinants of returns to floricultural plant production in the state. Data used for the study were collected from the forty one registered floricultural plant producers in the study area using structured questionnaire. The farm budget and regression analyses were used for data analyses. The study revealed that returns to farmer’s labour and management was N174, 974.7/ha on the average. Use of manure, labour, farm size, experience, educational level and age of the farmer were found to have significant influence on farmer’s revenue. Inadequate capital to expand the scale of production was identified as the major constraints to floricultural plant production in the study area. The study therefore recommends that farmers be supported by making credit facilities available to them and that people be enlightened on the profitability potential of the enterprise.

  11. Characterization of Potential Plant Growth Promoting Rhizobacteria Isolated from Maize (Zea mays L. in Central and Northern Benin (West Africa

    Directory of Open Access Journals (Sweden)

    Nadège A. Agbodjato

    2015-01-01

    Full Text Available Our study aims to characterize Plant Growth Promoting Rhizobacteria (PGPR isolated from maize roots in five agroecological zones of central and northern Benin. Sixty samples were collected at the rate of four samples per village and three villages per agroecological zone. Rhizobacteria strains were isolated from these samples and biochemically characterized. These strains were analyzed for some of their PGPR traits like ammonia production and hydrogen cyanide following conventional methods. Microbiological investigation of these samples has shown that maize rhizospheres in central and northern Benin contain a high diversity of microorganisms. A total of nine species of maize Plant Growth Promoting Rhizobacteria were identified. Those PGPR include five Bacillus species (B. polymyxa, B. pantothenticus, B. anthracis, B. thuringiensis, and B. circulans, three Pseudomonas species (P. cichorii, P. putida, and P. syringae, and Serratia marcescens. The microbial diversity does not depend on the soil types. The microbial density, generally high, varies according to both soil types and agroecological zones. All Serratia strains (100% have produced ammonia, whereas 80% of Bacillus and 77.77% of Pseudomonas produced this metabolite. The hydrogen cyanide was produced by all isolates (100% independent of their genus. These results suggest the possibility to use these rhizobacteria as biological fertilizers to increase maize production.

  12. 2014 Annual Wastewater Reuse Report for the Idaho National Laboratory Site’s Central Facilities Area Sewage Treatment Plant

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Mike [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-02-01

    This report describes conditions, as required by the state of Idaho Wastewater Reuse Permit (#LA-000141-03), for the wastewater land application site at the Idaho National Laboratory Site’s Central Facilities Area Sewage Treatment Plant from November 1, 2013, through October 31, 2014. The report contains, as applicable, the following information; Site description; Facility and system description; Permit required monitoring data and loading rates; Status of compliance conditions and activities; and Discussion of the facility’s environmental impacts. The current permit expires on March 16, 2015. A permit renewal application was submitted to Idaho Department of Environmental Quality on September 15, 2014. During the 2014 permit year, no wastewater was land-applied to the irrigation area of the Central Facilities Area Sewage Treatment Plant and therefore, no effluent flow volumes or samples were collected from wastewater sampling point WW-014102. Seepage testing of the three lagoons was performed between August 26, 2014 and September 22, 2014. Seepage rates from Lagoons 1 and 2 were below the 0.25 inches/day requirement; however, Lagoon 3 was above the 0.25 inches/day. Lagoon 3 has been isolated and is being evaluated for future use or permanent removal from service.

  13. Grey Relational Analysis on the Effects of Rainfall Factors on Runoff and Sediment in the Sloping Farmland with Different Plants in the Central South of Shandong Province

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The aim was to study the main rainfall factors influencing runoff and sediment in the sloping farmland with different plants in the central south of Shandong Province.[Method] Through grey relational analysis,the effects of different rainfall factors on runoff and sediment with different plants in the central south of Shandong were studied.[Result] In the sloping farmland with different plants,the effects of rainfall factors on runoff and sediment weren't consistent.Rainfall was the dominant inf...

  14. Central European plant species from more productive habitats are more invasive at a global scale

    OpenAIRE

    Dostal, Petr; Dawson, Wayne; van Kleunen, Mark; Keser, Lidewij H.; Fischer, Markus

    2013-01-01

    Aim: Accumulating evidence indicates that species may be pre-adapted for invasionsuccess in new ranges. In the light of increasing global nutrient accumulation,an important candidate pre-adaptation for invasiveness is the ability to grow innutrient-rich habitats. Therefore we tested whether globally invasive species originating from Central Europe have come from more productive rather than lessproductive habitats. A further important candidate pre-adaptation for invasivenessis large niche wid...

  15. 区域集中供热系统水力平衡探讨%Hydraulic balance of district central heating systems

    Institute of Scientific and Technical Information of China (English)

    杨国军

    2011-01-01

    从理论上分析了水力失调现象,提出了有效的水力平衡调节方法.详细探讨了区域集中供热系统的两种集中控制策略:流量控制和温度控制.%Analyses hydraulic disorder occurrences theoretically, and presents effective regulation methods.Discusses the two central control strategies i.e.flow rate control and temperature control for district central heating system in detail.

  16. Development of Natural Gas Fired Combined Cycle Plant for Tri-Generation of Power, Cooling and Clean Water Using Waste Heat Recovery: Techno-Economic Analysis

    OpenAIRE

    Gowtham Mohan; Sujata Dahal; Uday Kumar; Andrew Martin; Hamid Kayal

    2014-01-01

    Tri-generation is one of the most efficient ways for maximizing the utilization of available energy. Utilization of waste heat (flue gases) liberated by the Al-Hamra gas turbine power plant is analyzed in this research work for simultaneous production of: (a) electricity by combining steam rankine cycle using heat recovery steam generator (HRSG); (b) clean water by air gap membrane distillation (AGMD) plant; and (c) cooling by single stage vapor absorption chiller (VAC). The flue gases liber...

  17. Bioprospecting in potato fields in the Central Andean Highlands: screening of rhizobacteria for plant growth-promoting properties.

    Science.gov (United States)

    Ghyselinck, Jonas; Velivelli, Siva L S; Heylen, Kim; O'Herlihy, Eileen; Franco, Javier; Rojas, Mercy; De Vos, Paul; Prestwich, Barbara Doyle

    2013-03-01

    The Central Andean Highlands are the center of origin of the potato plant (Solanum tuberosum). Ages of mutualism between potato plants and soil bacteria in this region support the hypothesis that Andean soils harbor interesting plant growth-promoting (PGP) bacteria. Therefore, the aim of this study was to isolate rhizobacteria from Andean ecosystems, and to identify those with PGP properties. A total of 585 bacterial isolates were obtained from eight potato fields in the Andes and they were screened for suppression of Phytophthora infestans and Rhizoctonia solani. Antagonistic mechanisms were determined and antagonistic isolates were further tested for phosphate solubilization, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, and production of NH3- and indole-3-acetic acid (IAA). PGP was studied in healthy and R. solani diseased plantlets under growth room conditions. Performance was compared to the commercial strain B. subtilis FZB24(®) WG. Isolates were dereplicated with matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS), and identified with 16S rRNA gene sequencing and multi locus sequence analysis (MLSA). A total of 10% of the isolates were effective antagonists, of which many were able to solubilize phosphate, and produce IAA, ACC deaminase, NH3 and hydrogen cyanide (HCN). During growth room experiments, 23 antagonistic isolates were associated with plant growth-promotion and/or disease suppression. Ten isolates had a statistically significant impact on test parameters compared to the uninoculated control. Three isolates significantly promoted plant growth in healthy plantlets compared to the commercial strain, and seven isolates outperformed the commercial strain in in vitro R. solani diseased plantlets.

  18. Germination of nine species of a pioneer plant community of pliocene clay soils of central western italy under different photo- and thermo-periods

    Directory of Open Access Journals (Sweden)

    Aldemaro Boscagli

    2014-02-01

    Full Text Available Germination response under different photo- and thermo-periods was investigated in nine species of the association Parapholido-Artemisietum cretaceae, a typical plant community of clay badland vegetation in central western Italy. The species showed: (i more rapid germination under the photo- and thermo-period emulating autumn conditions than under the one emulating early spring conditions; (ii different germination rates under condition emulating periods with high diurnal insolation followed by high or low nocturnal heat dispersion: Aegilops geniculata, Parapholis strigosa and Artemisia cretacea were indifferent, Hordeum maritimum, Trifolium scabrum, Brachypodium distachyum and Parapholis incurva responded positively to higher thermal dispersion, whereas Medicago minima and Scorpiurus muricatus responded negatively; (iii different responses to a constant low temperature of 2oC: Artemisia cretacea, Parapholis incurva, Parapholis strigosa and Scorpiurus muricatus showed complete or very high dormancy; the other species showed a germination capacity between 55 and 87% in the following decreasing order: Medicago minima > Hordeum maritimum > Trifolium scabrum > Aegilops geniculata > Brachypodium distachyum. All species had delayed and reduced germination responses at 2oC. Grasses showed prompt, quick and high germination as environmental conditions became more favourable; legumes showed a similar response when their coat-imposed dormancy was removed, while the asteracea A. cretacea showed only a moderate germination capacity and one of the lowest germination rates. Nomenclaure: Pignatti (1982.

  19. Lesão do colo do cafeeiro, causada pelo calor Collar injury- young coffe plants caused by heat

    Directory of Open Access Journals (Sweden)

    Coaracy M. Franco

    1961-01-01

    Full Text Available Tem sido observada ocasionalmente uma lesão no colo de cafeeiros novos ao nível do solo. .Estudos dc laboratório mostraram que o caule de cafeeiros novos foram danificados quando ao redor dêle se fêz circular água aquecida às temperaturas de 45 o 50ºC. O aquecimento da superfície do solo, compreendendo o colo de cafeeiro vegetando em laminados, com o auxílio de uma lâmpada de raios infravermelhos, resultou em lesão semelhante àquela observada nas culturas. Essa lesão apareceu em tratamentos cujas temperaturas estiveram entre 44 e 51°C. O fato dessas temperaturas serem freqüentemente observadas em solos expostos ao sol, sugere que a lesão do caule do cafeeiro, observada freqüentemente em cafèzais novos, seja conseqüência do aquecimento excessivo da superfície do solo pelos raios solares.A collar injury of young, field coffee plants at the soil level has been observed occasionally in the summer. The location of the abnormality and the season when it appears .suggested that excessive heating of the soil surface by the sun rays could be its cause. Two experiments were then conducted in the laboratory to investigate this bypothesis. The first experiment consisted in circulating water at the desired temperature around the stem ofyoung coffee plants, using the same apparatus described in a previous paper. In a second experiment the base of the stem and the soil around it was heated by means of a G. E. 250 watts infrared industrial reflector. By changing the distance between the heat source and the plant, different temperatures at the soil surface could be obtained. The results of the first experiment showed that 4 plants out of o that were treated at 45ºC showed injury; the other 2 plants survived without damage. From 5 plants that were treated at 50ºC, 2 showed injury and 3 died shortly after the treatment. All plants subjected to the temperature treatments at 35°C and 40ºC survived without damage, while those treated at 55º

  20. Wet and dry cooling systems optimization applied to a modern waste-to-energy cogeneration heat and power plant

    Energy Technology Data Exchange (ETDEWEB)

    Barigozzi, G.; Perdichizzi, A.; Ravelli, S. [Department of Industrial Engineering, Bergamo University (Italy)

    2011-04-15

    In Brescia, Italy, heat is delivered to 70% of 200.000 city inhabitants by means of a district heating system, mainly supplied by a waste to energy plant, utilizing the non recyclable fraction of municipal and industrial solid waste (800,000 tons/year, otherwise landfilled), thus saving annually over 150,000 tons of oil equivalent and over 400,000 tons of CO{sub 2} emissions. This study shows how the performance of the waste-to-energy cogeneration plant can be improved by optimising the condensation system, with particular focus on the combination of wet and dry cooling systems. The analysis has been carried out using two subsequent steps: in the first one a schematic model of the steam cycle was accomplished in order to acquire a knowledge base about the variables that would be most influential on the performance. In the second step the electric power output for different operating conditions was predicted and optimized in a homemade program. In more details, a thermodynamic analysis of the steam cycle, according to the design operating condition, was performed by means of a commercial code (Thermoflex {sup copyright}) dedicated to power plant modelling. Then the off-design behaviour was investigated by varying not only the ambient conditions but also several parameters connected to the heat rejection rate, like the heat required from district heating and the auxiliaries load. Each of these parameters has been addressed and considered in determining the overall performance of the thermal cycle. After that, a complete prediction of the cycle behaviour was performed by simultaneously varying different operating conditions. Finally, a Matlab {sup copyright} computer code was developed in order to optimize the net electric power as a function of the way in which the condensation is operated. The result is an optimum set of variables allowing the wet and dry cooling system to be regulated in such a way that the maximum power is achieved. The best strategy consists in

  1. Radiological protection in nuclear power plants; La proteccion radiologica en las centrales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Zorrilla R, S. [CFE. Central Laguna Verde, Km. 42.5 Carretera Cardel-Nautla, Veracruz (Mexico)

    2008-12-15

    This presentation sharing experiences which correspond to the nuclear power plant of Laguna Verde. This nuclear power plant is located at level 2 of four possible, in the classification performance of the World Association of Nuclear Operators (WANO), which means the mexican nuclear power plant is classified in terms of its performance indicators and above the average achieved by their counterparts americans and canadians. In the national context, the nuclear power plant of Laguna Verde has also been honored with several awards such as the National Quality Award, the Clean Industry Certificate, the distinction of Environmental Excellence and others of similar importance. For the standards of WANO, the basic idea is that there are shortcomings in one of nuclear power plant concern to all partners. The indicators used for the classification will always go beyond more compliance with regulations, which are assumed, and rather assume come or a path to excellence. Among the most important indicators are: the collective dose, the percentage of areas declared as contaminated, the number, type and tendency of contamination personal cases, the number of dosimetry alarms, the number of unplanned exposures, loss control of high radiation areas and the release of contaminated material outside the restricted areas. Furthermore, as already indicated, nuclear power plants are of special care situations, such as, carrying out work in areas with radiation fields of more than 15 mSv h{sup -1}, the movement of spent fuel in the reload floor. The consideration of the minimum total effective dose equivalent as a criterion for prescribing tools that reduce exposures, but may increase the external cases of contaminated casualties, the experience in portals such as workers subject to radiology, where exposure in industrial radiography, and so on. Special mention deserve the conditions generated during fuel reload stops, which causes a massive personnel movement, working simultaneously on

  2. A reconstruction of Atlantic Central African biomes and forest succession stages derived from modern pollen data and plant functional types

    Directory of Open Access Journals (Sweden)

    J. Lebamba

    2009-01-01

    Full Text Available New detailed vegetation reconstructions are proposed in Atlantic Central Africa from a modern pollen data set derived from 199 sites (Cameroon, Gabon and Congo including 131 new sites. In this study, the concept of plant functional classification is improved with new and more detailed plant functional types (PFTs and new aggregations of pollen taxa. Using the biomisation method, we reconstructed (1 modern potential biomes and (2 potential succession stages of forest regeneration, a new approach in Atlantic Central African vegetation dynamics and ecosystem functioning reconstruction. When compared to local vegetation, potential biomes are correctly reconstructed (97.5% of the sites and tropical evergreen to semi-evergreen forest (TRFO biome is well identified from semi-deciduous forest (TSFO biome. When the potential biomes are superimposed on the White's vegetation map, only 76.4% of the sites are correctly reconstructed. But using botanical data, correspondence and cluster analyses, the 43 sites from Congo (Mayombe evidence more affinities with those of central Gabon and so they can also be considered as correctly reconstructed as TRFO biome and White's map must be revised. In terms of potential succession stages of forest regeneration, the mature forest (TMFO is well differentiated from the secondary forest (TSFE, but inside this latter group, the young and the pioneer stages are not clearly identified due probably to their low sampling representation. Moreover, linked to their progressive and mosaic character, the boundaries between two forest biomes or two forest stages are not clearly detected and need also a more intensive sampling in such transitions.

  3. Communal heating statistics for seven selected sites. Heating energy consumption, heating cost, and carbon dioxide emissions of domestic buildings with central heating systems. Final report; Kommunale Heizspiegel fuer sieben ausgewaehlte Standorte. Heizenergieverbrauch, Heizkosten und CO{sub 2}-Emissionen von zentralbeheizten Wohngebaeuden. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Bade, M. [comp.

    1999-10-01

    Heating staticstics help to define potential energy savings, informing building owners, landlords and tenants on specific energy consumption and specific heating cost of centrally heated multiple dwellings and enabling them a comparison with other buildings of a community. Data are evaluated separately for natural gas, heating oil and district heat. Statistics are presented for the cities of Kiel, Hamburg, Dortmund, Naumburg, Dresden, Wiesbaden and Esslingen. The heating statistics were established in cooperation with heat metering and billing services and building societies in order to obtain a wide data base. [German] Heizpiegel koennen ein wirksames Instrument zur Ausschoepfung des vorhandenen Energiesparpotentials im Gebaeudebestand sein. Sie informieren Gebaeudeeigentuemer, Vermieter und Mieter ueber den spezifischen Heizenergieverbrauch und die spezifischen Heizkosten von zentralbeheizten Mehrfamiliengebaeuden und ermoeglichen gleichzeitig einen Vergleich mit dem uebrigen Gebaeudebestand einer Kommune bzw. Stadt. Die zur Erstellung von Heizspiegeln erforderliche Datenauswertung erfolgt getrennt nach den Energietraegern Erdgas, Heizoel und Fernwaerme. Im Rahmen des Projektes wurden fuer die Staedte Kiel, Hamburg, Dortmund, Naumburg, Dresden, Wiesbaden und Esslingen Heizspiegel erstellt. Bei der Erstellung der Heizspiegel konnte durch die Mitarbeit mehrerer Heizkosten-Verteilerfirmen und Wohnungsgesellschaften auf eine relativ breite Datenbasis zurueckgegriffen werden. (orig.)

  4. Identification of cotton fleahopper (Hemiptera: Miridae) host plants in central Texas and compendium of reported hosts in the United States.

    Science.gov (United States)

    Esquivel, J F; Esquivel, S V

    2009-06-01

    The cotton fleahopper, Pseudatomoscelis seriatus (Reuter), is an early-season pest of developing cotton in Central Texas and other regions of the Cotton Belt. Cotton fleahopper populations develop on spring weed hosts and move to cotton as weed hosts senesce or if other weed hosts are not readily available. To identify weed hosts that were seasonably available for the cotton fleahopper in Central Texas, blooming weed species were sampled during early-season (17 March-31 May), mid-season (1 June-14 August), late-season (15 August-30 November), and overwintering (1 December-16 March) periods. The leading hosts for cotton fleahopper adults and nymphs were evening primrose (Oenothera speciosa T. Nuttall) and Mexican hat [Ratibida columnifera (T. Nuttall) E. Wooton and P. Standley], respectively, during the early season. During the mid-season, silver-leaf nightshade (Solanum elaeagnifolium A. Cavanilles) was consistently a host for fleahopper nymphs and adults. Woolly croton (Croton capitatus A. Michaux) was a leading host during the late season. Cotton fleahoppers were not collected during the overwintering period. Other suitable hosts were available before previously reported leading hosts became available. Eight previously unreported weed species were documented as temporary hosts. A compendium of reported hosts, which includes >160 plant species representing 35 families, for the cotton fleahopper is provided for future research addressing insect-host plant associations. Leading plant families were Asteraceae, Lamiaceae, and Onagraceae. Results presented here indicate a strong argument for assessing weed species diversity and abundance for the control of the cotton fleahopper in the Cotton Belt.

  5. Low-temperature water reactor for the district heating atomic power plant

    Energy Technology Data Exchange (ETDEWEB)

    Skvortsov, S.A.; Sokolov, I.N.; Krauze, L.V.; Nikiporetz, Yu.G.; Philimonov, Y.V.

    1978-04-01

    A natural convection low-pressure water reactor can be utilized as a source of district heating. This provides inherent safety factors under conditions requiring emergency core cooling. The reactor pressure vessel is contained within a prestressed concrete shell, both of which are designed to withstand accident overpressure. This also results in a relatively thin-walled reactor vessel that can be fabricated on-site. The overall safety and economy of such a system merits further consideration as a system for providing low-temperature nuclear heat for district heating.

  6. New industrial heat pump applications to a synthetic rubber plant. Final report, Phase IIA

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-31

    This report summarizes the results of the Phase IIA of the DOE sponsored study titled, Advanced Industrial Heat Pump Application and Evaluation. The scope of this phase of the study was to finalize the process design of the heat pump scheme, develop a process and instrumentation diagram, and a detailed cost estimate for the project. This information is essential for the site management to evaluate the economic viability and operability of the proposed heat pump design, prior to the next phase of installation and testing.

  7. The Chernobyl plant shutdown; L'arret de la centrale de Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-12-01

    The Chernobylsk-1 reactor, operational in september 1977 has been stopped in november 1996; the Chernobylsk-2 reactor started in november 1978 is out of order since 1991 following a fire. The Chernobylsk-3 reactor began in 1981. During the last three years it occurs several maintenance operations that stop it. In june 2000, the Ukrainian authorities decided to stop it definitively on the 15. of december (2000). This file handles the subject. it is divided in four chapters: the first one gives the general context of the plant shutdown, the second chapter studies the supporting projects to stop definitively the nuclear plant, the third chapter treats the question of the sarcophagus, and the fourth and final chapter studies the consequences of the accident and the contaminated territories. (N.C.)

  8. Forest structure and plant diversity in maritime pine (Pinus pinaster Ait.) stands in central Spain

    Energy Technology Data Exchange (ETDEWEB)

    Osorio, L. F.; Bravo, F.; Zaldivar, P.; Pando, V.

    2009-07-01

    The relationship between forest structure and plant diversity in Mediterranean Maritime pine stands (Pinus pinaster Ait.) in the Iberian Range (Spain) was studied. Forty eight stands were sampled. In each, a circular plot (15 m radius) and a transect (25*1 m{sup 2}) were established to estimate stand variables and record presence and abundance of vascular species respectively. Canonical correlation analysis (CCA), simple correlations and multiple stepwise linear regressions were used to explore the relationship between plant diversity and forest structure. Correlation between diversity measurements and stand variables is very weak, but significant correlations were found when evaluating each set of variables separately. Presence and cover of some species (for instance, Veronica arvensis L. or Micropyrum tenellum (L.) Link) is correlated with stand variables; however, determination coefficients found in step-by-step regression are not significant. (Author) 34 refs.

  9. District heating and cooling systems for communities through power plant retrofit distribution network. Final report, September 1, 1978-May 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-10-01

    This volume presents information on the institutional factors, i.e., legal and regulatory aspects, a preliminary economic analysis, and a proposal for future studies on retrofitting existing thermal power plants so that they can supply heat for district heating and cooling systems for communities. (LCL)

  10. Development and Field Test of the Central Energy Plant Adaptive Control System (CEPACS)

    Science.gov (United States)

    1994-06-01

    conventional P11) mode. PID controllers implemented in pneumatic, electronic, or microcomputer software can be somewhat difficult to set up and may not...plan was repeated using digital PID controllers to create a comparison data set. Appendix A gives details of th" test plan. Test Difficuities Problems...backlash in the drive mechanism. The oscillation was also present when using the Abbott Power Plant continuous pneumatic PID controllers , but at a smaller

  11. Qualification of programmed systems in power plants; Qualification des systemes programmes dans les centrales

    Energy Technology Data Exchange (ETDEWEB)

    Legras, A.; Quenot, D. [Sema Group (France)

    1999-04-01

    This paper deals with the control system software and drive units of the recent nuclear power plants. After a general presentation on the software utility and the constraints such as economical factors, safety or availability, the authors present the normative documents and the regulations. The third part is devoted to concrete examples showing the technical choices to obtain the wanted quality. Forecasted projects are included in the last part. (A.L.0008).

  12. Engineering for new-built nuclear power plant projects; Ingenieria para proyectos de nuevas centrales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Lopez, A.

    2012-11-01

    This article reviews the opportunities existing in the market (electrical utilities and reactor vendors) for an engineering company with the profile of Empresarios Agrupados (EA) in new-built nuclear power plant projects. To do this, reference is made to some representative examples of projects in which EA has been participating recently. the article concludes sharing with the reader some lessons learned from this participation. (Author)

  13. Chemical and radiochemical specifications - PWR power plants; Specifications chimiques et radiochimiques - Centrales REP

    Energy Technology Data Exchange (ETDEWEB)

    Stutzmann, A. [Electricite de France (EDF), 93 - Saint-Denis (France)

    1997-07-01

    Published by EDF this document gives the chemical specifications of the PWR (Pressurized Water Reactor) nuclear power plants. Among the chemical parameters, some have to be respected for the safety. These parameters are listed in the STE (Technical Specifications of Exploitation). The values to respect, the analysis frequencies and the time states of possible drops are noticed in this document with the motion STE under the concerned parameter. (A.L.B.)

  14. Heating plants. Comparison between the main available techniques that allow heating plants to respect the new regulations; Les chaudieres. Comparaison des principales techniques disponibles permettant aux chaudieres de respecter les nouvelles reglementations

    Energy Technology Data Exchange (ETDEWEB)

    Bouju, J.L. [Babcock Entreprise, 93 - La Courneuve (France)

    1997-12-31

    This paper gives an overview of the main methods available today to improve the thermal and environmental performances of heating plants and burners and points out the technical and economical advantages and drawbacks of these methods. The methods are described according to the type of pollutant: SO{sub x} (fuel treatment, smokes desulfurization, in-situ desulfurizers injection, lime treatment of solid and liquid fuels), NO{sub x} (smokes recycling, low-NO{sub x} burners, air staging, over-dimensioning of combustion chambers, reduction of combustion air temperature, re-burning, denitrifier injection, combination of several methods), dusts (filters and cyclones). (J.S.)

  15. Data Series Generation for CPS Plants Simulation; Generacion de Series para Simulacion de Centrales Termosolares

    Energy Technology Data Exchange (ETDEWEB)

    Ibanez, G.; Valenzuela, R. X.; Ramirez, L.; Polo, J.

    2014-02-01

    Due to the problems with the environment and other issues arising from the use of oil as the main source of energy, such as unstable politics and economics, there has been a growing interest in the development of alternative forms of energy over the last few years. In this field, the sun is a fundamental element, since any form of existing energy derives from it, directly or indirectly. Taking in to consideration all of these renewable energies, we have decided to focus on solar thermal energy, seeing as it will play a vital role in the future particularly in countries such as Spain that have great solar potential. Amid this form of renewable energy, the parabolic cylinder concentrator power plants are technologies with one of the most promising futures. Power plants with sufficient technological developments to compete with the other forms of energies and that have an extensive margin for improvement. These power plants are the subject of the investigations carried out in this project. This project will try