Exhaust Gas (exhaust + gas)

Distribution by Scientific Domains

Terms modified by Exhaust Gas

  • exhaust gas recirculation

  • Selected Abstracts


    Simultaneous Catalytic Removal of Nitrogen Oxides and Soot from Diesel Exhaust Gas over Potassium Modified Iron Oxide

    CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 9 2003
    S. Kureti
    Abstract Iron oxide modified by potassium, i.e. Fe1.9K0.1O3, exhibits high catalytic performance for the simultaneous conversion of soot and NOx into CO2 and N2. The present study shows that long-time treatment of the catalyst leads to a drastic decrease in the activity, whereas even the aged catalyst maintains considerable activity. On the other hand, long-time treatment causes selective N2 formation, i.e. no more formation of the byproduct N2O. This alteration of catalytic performance is likely due to agglomeration of the promoter potassium being present at the surface of catalyst. Detailed experiments were carried out with a more realistic diesel model exhaust gas to confirm that Fe1.9K0.1O3 is a suitable catalyst for the simultaneous removal of soot and NOx between 350 and 480 °C. It was assumed that (CO) intermediates, formed by the catalytic reaction of NOx and oxygen with the soot surface, are the reactive species in NOx -soot conversion. [source]


    Proposal and evaluation of a gas engine and gas turbine hybrid cogeneration system in which cascaded heat is highly utilized

    ELECTRICAL ENGINEERING IN JAPAN, Issue 3 2009
    Pyong Sik Pak
    Abstract A high-efficiency cogeneration system (CGS) is proposed for utilizing high-temperature exhaust gas (HTEG) from a gas engine (GE). In the proposed system, for making use of heat energy of HTEG, H2O turbine (HTb) is incorporated and steam produced by utilizing HTEG is used as working fluid of HTb. HTb exhaust gas is also utilized for increasing power output and for satisfying heat demand in the proposed system. Both of the thermodynamic characteristics of the proposed system and a gas engine CGS (GE-CGS) constructed by using the original GE are estimated. Energy saving characteristics and CO2 reduction effects of the proposed CGS and the GE-CGS are also investigated. It was estimated that the net generated power of the proposed CGS has been increased 25.5% and net power generation efficiency 6.7%, compared with the original GE-CGS. It was also shown that the proposed CGS could save 27.0% of energy consumption and reduce 1137 t-CO2/y, 1.41 times larger than those of GE-CGS, when a case study was set and investigated. Improvements of performance by increasing turbine inlet temperature were also investigated. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(3): 37, 45, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20708 [source]


    Performance characteristics and modelling of a micro gas turbine for their integration with thermally activated cooling technologies

    INTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 2 2007
    Adrián Vidal
    Abstract We have developed a simple model of a micro gas turbine system operating at high ambient temperatures and characterized its performance with a view to integrating this system with thermally activated cooling technologies. To develop and validate this model, we used experimental data from the micro gas turbine test facility of the CREVER research centre. The microturbine components were modelled and the thermodynamic properties of air and combustion gases were estimated using a commercial process simulator. Important information such as net output power, microturbine fuel consumption and exhaust gas mass flow rate can be obtained with the empirical correlations we have developed in this study. This information can be useful for design exhaust gas fired absorption chillers. Copyright © 2006 John Wiley & Sons, Ltd. [source]


    A new type of EFHAT power generation system with effective utilization of latent heat

    INTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 13 2005
    Hongguang Jin
    Abstract On the basis of synergetic integration of an externally fired humid air turbine (EFHAT) cycle and effective recovery of latent heat from the exhaust gas of gas turbine, we have proposed a new type of EFHAT power generation system with effective utilization of latent heat, different from traditional EFHAT system. Due to use of clean humid air as working substance, latent heat can be recovered and utilized to generate hot water for the humidifier. This will enhance the humidification ability, giving rise to performance improvement of the system. As a result, at the turbine inlet temperature of 1123 K, the thermal efficiency of this new system may be expected to be as high as 47,48%. Additionally, we obtained the analytical expressions of system performance, and disclosed the relative relationship of system efficiency between the new EFHAT system and the pure externally fired power system. Copyright © 2005 John Wiley & Sons, Ltd. [source]


    Theoretical performance analysis of the multi-stage gas,solid fluidized bed air preheater

    INTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 10 2001
    Sang Il Park
    Abstract The multi-stage fluidized bed can be used to preheat the combustion air by recovering the waste heat from the exhaust gas from industrial furnaces. The dilute-phase fluidized bed may be formed to exclude the excessive pressure drop across the multi-stage fluidized bed. But, in this case, the solid particles do not reach to the thermal equilibrium due to relatively short residence time in each layer of fluidized bed. In this study, a theoretical analysis on the dilute phase multistage fluidized bed heat exchanger was performed. A parameter related to the degree of thermal equilibrium between gas and solid particles at the dilute-phase fluidized beds was derived. Using this parameter, a relatively simple expression was obtained for the thermal efficiencies of the multi-stage fluidized bed heat exchanger and air preheater. Copyright © 2001 John Wiley & Sons, Ltd. [source]


    Pulsed dielectric barrier discharge reactor for diesel particulate matter removal

    AICHE JOURNAL, Issue 8 2004
    S. Yao
    Abstract A dielectric barrier discharge (DBD) reactor, driven by a pulsed corona surface discharge (PCSD), was developed for the removal of particulate matter (PM) in an undiluted exhaust gas of a diesel engine. The DBD reactor consisted mainly of alumina (Al2O3) plates and metal meshes covered on the surfaces of Al2O3 plates. The PCSD was carried out with a pulse power supply at atmospheric pressure and the temperature of exhaust gases. The energy efficiency for PM removal was 26.5 ,g/J at maximum and 1 ,g/J with 42% PM removal. The construction of the DBD reactor that promoted PM deposition on Al2O3 surfaces improved energy efficiency. The constants in PM removal model were given. © 2004 American Institute of Chemical Engineers AIChE J, 50: 1901,1907, 2004 [source]


    A method of measuring oil consumption by labelling with radioactive bromine

    LUBRICATION SCIENCE, Issue 3 2000
    H. Zellbeck
    Abstract A method of determining the oil consumption rate of combustion engines is presented. It is based on labelling the individual oil fractions of engine oil with radioactive bromine isotope82 Br and on the quantitative absorption of radioactive bromine compounds in the exhaust gas in an aqueous solution of nitric acid and silver nitrate. The advantages of this method are that the oil that is consumed in the exhaust gas can be directly measured, without the fluctuating amounts of oil in the sump influencing the result, and the behaviour of the individual components of the oil in the consumption process can be determined. The test is quick, only twenty minutes being required to detect oil consumption at one operating point; and with a single labelling, the oil consumption at a great number of working engine points can be measured 82 Br has a short half-life of only 36 h, so that compliance with radiation protection measures is inexpensive and investigations can be carried out using a conventional testing device. As part of the research project, a study was made of the influence of different base oil types, with and without polymer additives, on consumption. Results showed that Noack evaporation loss correlated with oil consumption only with boiling fractions of exactly the same base oil, and not with different, in particular synthetic, base oils; that polymer additives (VI improvers) significantly reduced the rate of oil consumption; and that the polymer additive and the type of base oil both had more influence on oil consumption than viscosity. [source]


    Particulate Matter Removal from Diesel Exhaust Gases by a Combination of Corona Discharge and Water or Oil Bath

    PLASMA PROCESSES AND POLYMERS, Issue 9 2006
    Yoshio Yoshioka
    Abstract Summary: As an efficient PM removal method from diesel exhausts, we developed a new method using a combination of a DC corona discharge and oil or water trays. The PM removal device generates DC corona discharges on oil or water filled in trays, thereby creating charges on the PMs, which can then be accelerated by an electric field towards the oil or water bath. The amount of PM absorbed in oil is determined by measuring light transmission. The discharge current on water is higher than that on oil. The difference of these discharge currents is considered to be due to the difference in ion mobility of the two liquids. An equation for PM removal characteristics is proposed. Using the equation, the PM removal by our device is estimated to be more than 85%. Experimental system for PM removal from diesel engine exhaust gas. [source]


    Development of a system for the on-line measurement of carbon dioxide production in microbioreactors: Application to aerobic batch cultivations of Candida utilis

    BIOTECHNOLOGY PROGRESS, Issue 3 2009
    Michiel van Leeuwen
    Abstract We developed and applied a conductometric method for the quantitative online measurement of the carbon dioxide (CO2) production during batch cultivations of Candida utilis on a 100-,L scale. The applied method for the CO2 measurement consisted of absorption of the produced CO2 from the exhaust gas of the microbioreactor in an alkali solution, of which the conductivity was measured on-line. The measured conductivity change of the alkali solution showed a linear relation with the total amount of CO2 absorbed. After calibration of the CO2 measurement system, it was connected to a well of a 96-well microtiter plate. The mixing in the well was achieved by a magnetic stirrer. Using online measurement of the CO2 production during the cultivation, we show reproducible exponential batch growth of C. utilis on a 100-,L scale. The CO2 production measurements obtained from the microcultivation were compared with the CO2 production measurement in a 4-L bioreactor equipped with a conventional off-gas analyzer. The measurements showed that on-line measurement of the CO2 production rate in microbioreactors can provide essential data for quantitative physiological studies and provide better understanding of microscale cultivations. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source]


    Simultaneous Catalytic Removal of Nitrogen Oxides and Soot from Diesel Exhaust Gas over Potassium Modified Iron Oxide

    CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 9 2003
    S. Kureti
    Abstract Iron oxide modified by potassium, i.e. Fe1.9K0.1O3, exhibits high catalytic performance for the simultaneous conversion of soot and NOx into CO2 and N2. The present study shows that long-time treatment of the catalyst leads to a drastic decrease in the activity, whereas even the aged catalyst maintains considerable activity. On the other hand, long-time treatment causes selective N2 formation, i.e. no more formation of the byproduct N2O. This alteration of catalytic performance is likely due to agglomeration of the promoter potassium being present at the surface of catalyst. Detailed experiments were carried out with a more realistic diesel model exhaust gas to confirm that Fe1.9K0.1O3 is a suitable catalyst for the simultaneous removal of soot and NOx between 350 and 480 °C. It was assumed that (CO) intermediates, formed by the catalytic reaction of NOx and oxygen with the soot surface, are the reactive species in NOx -soot conversion. [source]