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1

Exhaust gas temperature measuring system utilizing existing oxygen sensor  

Energy Technology Data Exchange (ETDEWEB)

An exhaust gas temperature measuring system for an internal combustion engine having an oxygen sensor connected to provide an input to a closed-loop stoichiometric fuel control system, the oxygen sensor characterized by an intrinsic voltage responsive to an air/fuel ratio to generate a low voltage value in response to a lean air/fuel ratio and a high voltage value in response to a rich air/fuel ratio is described comprising, in combination: an oxygen sensor disposed in an exhaust gas stream of the engine, the oxygen sensor having an internal resistance corresponding to exhaust gas temperature according to a known relationship and further having means for generating an intrinsic voltage electrically in series with the internal resistance between a pair of terminals; means for measuring an unloaded sensor voltage across the pair of terminals; means for loading the sensor with a known resistive load across the pair of terminals and measuring a loaded sensor voltage across the pair of terminals; means for determining the internal resistance exclusively from the loaded and unloaded sensor voltages; and means for determining the exhaust gas temperature corresponding to the internal resistance according known relationship.

Ker, E.L.; Peterson, P.R.

1993-06-15

2

Exhaust gas suppressor  

Energy Technology Data Exchange (ETDEWEB)

An exhaust gas suppressor which suppresses the generation of harmful gases contained in exhaust gases from internal combustion engines, wherein secondary air is efficiently heated to high temperature by a coiled heater tube installed in the exhaust manifold of the internal combustion engine and is added to a mixture of primary air and fuel present in the suction manifold, the mixture being then fed to an eddy generating device which generates eddies in the mixture for complete gasification.

Fukumoto, M.

1982-12-07

3

Exhaust gas recirculation control  

Energy Technology Data Exchange (ETDEWEB)

An exhaust gas recirculation control assembly senses a throttle position related vacuum signal, an engine speed related pressure, and atmospheric pressure to create a subatmospheric control pressure suitable for actuating a diaphragm operated exhaust gas recirculation control valve.

Romblom, E.R.

1983-06-14

4

Exhaust gas recycling system  

Energy Technology Data Exchange (ETDEWEB)

A system is disclosed for treating exhaust gases from an internal combustion engine wherein solid particles contained in the exhaust gas stream are retained in a filter bed, and are then controllably combusted in a manner to avoid thermal damage to the particle retaining bed.

Crone, J.M.

1980-08-19

5

Exhaust gas recirculation control assembly  

Energy Technology Data Exchange (ETDEWEB)

An exhaust gas recirculation valve pintle is secured on a hollow valve stem by a radially elastic retaining ring which allows the pintle to be withdrawn from the stem for removal of exhaust gas deposits.

Blanchette, J.A.

1982-12-21

6

Processing of exhaust gas  

International Nuclear Information System (INIS)

Silicon carbide is an important component in exhaust gas filters for diesel engines. Norway produces and refines SiC, which is used in fireproof and ceramic industry and as an abrasive. It is also increasingly used in electronic industry. The emission from diesel engines consists of small spherical soot particles with an appendage of fuel, lubricating oil, water and sulphur compounds. These particles are intercepted by silicon carbide filters. There is a world-wide demand for environmentally friendly diesel engines and a growing demand for silicon carbide. From 2002, the EU permits a maximum emission of 0.025 grams per km of driving

2001-01-01

7

40 CFR 86.509-90 - Exhaust gas sampling system.  

Science.gov (United States)

...Using Alternative Fuels,â EPA 460...exhaust gas) temperature does not exceed...methanol-fueled motorcycles). (6...Emissions and Fuel Economy When Using Alternative Fuels,â EPA 460...exhaust gas) temperature does not exceed...methanol-fueled motorcycles)....

2010-07-01

8

Water recovery from HAT cycle exhaust gas: a possible solution for reducing stack temperature problems  

Energy Technology Data Exchange (ETDEWEB)

For several years the injection steam into the combustion chamber has represented a common way to improve the performance of gas turbine power plants, increasing both the power output and the efficiency and reducing, at the same time, NO{sub x} emissions. Starting from the first STeam Injected Gas turbine (GE STIG) cycles, several types of gas turbine cycle with steam or water injection (dual fluid cycles) have been proposed. Among them, the most interesting results were obtained with the Cheng and the humid air turbine (HAT) cycles. In particular, the HAT cycle (which is a gas turbine cycle featuring intercooled compression, an air-water mixing evaporator before the combustion chamber, and a recovery system for the exhaust gases) has been identified as a promising way to generate electric power at high efficiency, low cost and with a system that is simple compared with the combined cycles (Stecco et al. and Gallo et al.). However the associated water consumption, about 1210-2420 m{sup 3} per day for a 100 MW unit, continues to represent a significant drawback to the spread of the HAT cycle, as well as of other steam injected cycles. One of the possible solutions is the introduction of an induced draft fan (IDF), the other is recuperative heating of the exhaust gases after condenser. The results show that the IDF can increase the cycle efficiency and that a significant amount of heat and water can be recovered from the exhaust gases. (author)

Desideri, U.; Di Maria, F. [Perugia Univ. (Italy). Ist. di Energetica

1997-07-01

9

Process for minimising exhaust gas temperatures of chimneys and to improve the draught. Verfahren zur Minimierung von Abgastemperaturen in Schornsteinanlagen und zur Verbesserung der Zugverhaeltnisse  

Energy Technology Data Exchange (ETDEWEB)

The invention concerns a process for controlling exhaust gas temperatures in chimneys and smoke stacks. For this purpose a suction and acceleration section is fitted in the chimney, consisting of a circular duct, for sucking the stack gas in and a previous acceleration nozzle, through which the stack gas is returned to the chimney. A fan connected to the exhaust gas circular duct takes the stack gas through a heat exchanger, where is cooled. A measuring system optimises heat recovery. The draught of the chimney is improved by the simultaneous acceleration of the exhaust gas in the centre of the chimney.

Rode, W.

1982-11-25

10

Gas turbine exhaust system silencing design  

International Nuclear Information System (INIS)

Gas turbines are the preferred prime mover in many applications because of their high efficiency, fuel flexibility, and low environmental impact. A typical mid-size machine might have a power rating of 80 MW, a flow of about 1000 kg/hr, and an exhaust temperature of over 500C. The most powerful single source of noise is generally the exhaust, which may generate over a kilowatt of acoustic energy. This paper reports that there are two important ways in which exhaust systems can radiate noise. The first is through the discharge of the exhaust duct, with the exhaust gas. Because of the large quantity of hot gas, the duct exit is always oriented vertically; it may be fairly high in the air in order to promote dispersion of the exhaust plume. This source is almost always attenuated by means of a silencer located somewhere in the ductwork. The second source of noise is often called breakout; it is the radiation of exhaust noise through the walls of the ducting. Breakout is most important for those sections of the exhaust duct which lie upstream of the silencer, where sound levels inside the ducting are highest. Both exhaust duct exit noise and breakout noise can be calculated from the sound power level of the gas turbine exhaust and the sound transmission loss (TL) of the silencer and ducting

1991-07-14

11

Comparison of sound, exhaust gas temperature and smoke opacity characteristics of methyl esters of vegetable oils blends  

Directory of Open Access Journals (Sweden)

Full Text Available Experimental studies were conducted to evaluate the sound, exhaust gas temperature and smoke opacity characteristics of a single cylinder, four stroke engine fuelled with Vegetable oil methyl ester and its blends with standard diesel. Among different vegetable oils which can be used as alternate fuels, five vegetable oils, i.e., Nerium (Nerium oleander, Jatropha (Jatropha curcas, Pongamia (Pongamia pinnata, Mahua (Madhuca indica and Neem (Azadirachta indica oils were selected for analysis. Tests has been conducted using the fuel blends of 20%, 40%, 60% and 80% biodiesel with standard diesel, with an engine speed of 1800 rpm. It has found that the sound, exhaust gas temperature and smoke opacity characteristics of vegetable oil methyl ester and its diesel blends closely followed those of standard diesel.

S. Prabhakar

2011-10-01

12

Time-resolved nature of exhaust gas emissions and piston wall temperature under transient operation in a small diesel engine  

Energy Technology Data Exchange (ETDEWEB)

Diesel combustion and exhaust gas emissions under transient operation (when fuel amounts abruptly increased) were investigated under a wide range of operating conditions with a newly developed gas sampling system. The relation between gas emissions and piston wall temperatures was also investigated. The results indicated that after the start of acceleration NOx, THC and smoke showed transient behaviors before reaching the steady state condition. Of the three gases, THC was most affected by piston wall temperature; its concentration decreased as the wall temperature increased throughout the acceleration except immediately after the start of acceleration. The number of cycles, at which gas concentrations reach the steady-state value after the start of acceleration, were about 1.2 times the cycle constant of the piston wall temperature for THC, and 2.3 times for smoke.

Reksowardojo, I.K.; Ogawa, Hideyuki; Miyamoto, Noboru [Hokkaido Univ., Sapporo (Japan); Enomoto, Yoshiteru [Musashi Inst. of Tech., Tokyo (Japan); Kitamura, Toru

1996-09-01

13

Comparison of sound, exhaust gas temperature and smoke opacity characteristics of methyl esters of vegetable oils blends  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Experimental studies were conducted to evaluate the sound, exhaust gas temperature and smoke opacity characteristics of a single cylinder, four stroke engine fuelled with Vegetable oil methyl ester and its blends with standard diesel. Among different vegetable oils which can be used as alternate fuels, five vegetable oils, i.e., Nerium (Nerium oleander), Jatropha (Jatropha curcas), Pongamia (Pongamia pinnata), Mahua (Madhuca indica) and Neem (Azadirachta indica) oils were selected for analysi...

2011-01-01

14

Electrochemical Exhaust Gas Purification  

DEFF Research Database (Denmark)

This text is divided into two parts; the first part gives a short recapitulation of the development status of the electrochemical reactor for soot removal, while the second part gives a description of activities on electrochemical NOx reduction. The Electrochemical Reactor for filtration and continuous combustion of soot from diesel exhaust gas has been described earlier [1, 2]. The reactor size has been increased by stacking flat plate reactors, and full size test has been performed on a diesel engine in a test bench. The soot removal efficiency is better than 90%, but the efficiency for gas oxidation (conversion of carbon monoxide (CO) and hydrocarbons (CH)) is still low, of the order of 50%. The packing and mounting of the reactor is under development to avoid mechanical breakage by engine vibrations. This has improved the durability significantly, and on road vehicle test is under initiation. Optimisation of reactor shape and materials are going on continuously to improve efficiency and durability. In this phase various production methods are under consideration. Activity to extend the electrochemical principle to lean NOx removal is increasing. In this work a concept for electrochemical removal of NOx under lean conditions is outlined. The main obstacles to the design of an effective and energy efficient electrochemical DeNOx reactor are presented. The use of a selective electrode in combination with the need to be able to control the applied potential and, following from this, the need for a simple geometry of the reactor is stressed. A selective electrode for nitric oxide reduction has been identified.

Christensen, Henrik; Dinesen, Jørgen

2000-01-01

15

Orifice of exhaust gas recirculation system  

Energy Technology Data Exchange (ETDEWEB)

In an exhaust gas recirculation system for an internal combustion engine, orifices disposed in a passage for recirculating the exhaust gas is made of a sheet of a bimetal or other material capable of changing from a normal shape to a deformed shape when the heat of the exhaust gas is applied, in order to prevent carbon contained in the exhaust gas from depositing on the orifices.

Fukae, Y.

1984-10-09

16

Vehicle Exhaust Gas Clearance by Low Temperature Plasma-Driven Nano-Titanium Dioxide Film Prepared by Radiofrequency Magnetron Sputtering  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A novel plasma-driven catalysis (PDC) reactor with special structure was proposed to remove vehicle exhaust gas. The PDC reactor which consisted of three quartz tubes and two copper electrodes was a coaxial dielectric barrier discharge (DBD) reactor. The inner and outer electrodes firmly surrounded the outer surface of the corresponding dielectric barrier layer in a spiral way, respectively. Nano-titanium dioxide (TiO2) film prepared by radiofrequency (RF) magnetron sputtering was coated on t...

Yu, Shuang; Liang, Yongdong; Sun, Shujun; Zhang, Kai; Zhang, Jue; Fang, Jing

2013-01-01

17

Development of high temperature SiC based field effect sensors for internal combustion engine exhaust gas monitoring  

Digital Repository Infrastructure Vision for European Research (DRIVER)

While the car fleet becomes increasingly larger it is important to lower the amounts of pollutants from each individual diesel or gasoline engine to almost zero levels. The pollutants from these engines predominantly originate from high NOx emissions and particulates, in the case when diesel is utilized, and emissions at cold start from gasoline engines. One way of treating the high NOx levels is to introduce ammonia in the diesel exhausts and let it react with the NOx to form nitrogen gas an...

Wingbrant, Helena

2003-01-01

18

Effects of exhaust temperature on helicopter infrared signature  

International Nuclear Information System (INIS)

The effects of exhaust temperature on infrared signature (in 3–5 ?m band) for a helicopter equipped with integrative infrared suppressor were numerically investigated. The internal flow of exhaust gas and the external downwash flow, as well as the mixing between exhaust gas and downwash were simulated by CFD software to determine the temperature distributions on the helicopter skin and in the exhaust plume. Based on the skin and plume temperature distributions, a forward–backward ray-tracing method was used to calculate the infrared radiation intensity from the helicopter with a narrow-band model. The results show that for a helicopter with its integrative infrared suppressor embedded inside its rear airframe, the exhaust temperature has significant influence on the plume radiation characteristics, while the helicopter skin radiation intensity has little impact. When the exhaust temperature is raised from 900 K to 1200 K, the plume radiation intensity in 3–5 ?m band is increased by about 100%, while the skin radiation intensity is increased by only about 5%. In general, the effects of exhaust temperature on helicopter infrared radiation intensity are mainly concentrated on plume, especially obvious for a lower skin emissivity case. -- Highlights: ? The effect of exhaust temperature on infrared signature for a helicopter is numerically investigated. ? The impact of exhaust temperature on helicopter skin temperature is revealed. ? The impact of exhaust temperature on plume radiation characteristics is revealed. ? The impact of exhaust temperature on helicopter skin radiation is revealed. ? The impact of exhaust temperature on helicopter's total infrared radiation intensity is revealed

2013-03-01

19

Dynamics of exhaust gas generated by arc extinction  

Science.gov (United States)

We report an analytical study on hot gas exhaust process of a SF6 gas circuit breaker (GCB), after current interruption. The behavior of the hot gas has been studied based on measured gas temperature and simulation results of gas composition. We also propose a mechanism of interaction between the hot gas and pressure waves, which causes a self-blocking of the exhaust gas. During the heavy current interruption, the flow model suggests that the dielectric strength of the hot gas is affected by the pressure waves that are generated by the hot gas exhaustion. We believe that the results reported in this article provide guidance for the optimum structure of the exhaust chamber for small size GCB, operating at very high interrupting current.

Hayashi, Yasushi; Watanabe, Masato; Okino, Akitoshi; Hotta, Eiki

2001-11-01

20

Exhaust gas turbo supercharger. Abgasturbolader  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the invention is to create an exhaust gas turbo supercharger, in which the radially divided bearings are situated between the running discs, and the material stress limiting the speed is about the same in both running discs. According to the invention, this problem is solved by making the other running disc as a full disc with a shaft stub, and by this shaft stub being made as a bolt for one running disc and as a hole for the axial fixing of the bolt for the other running disc. The particular advantages of this design are that the axial mounting can be ratained and that for a given material, it is possible to raise the limiting speed of rotation. (HWJ).

Ruetz, G.

1983-10-20

 
 
 
 
21

Exhaust gas cleaning plants in field experiment  

International Nuclear Information System (INIS)

This research and development project has the following aims: Measurement of exhaust gas cleaning of engine-driven heat generation plants in the field experiment; Suitability of emission hand measurement equipment for discontinuous testing of the exhaust gas cleaning plant by the operator; Testing new methods of reducing the harmful substances in engine and conventional heat generators. (orig.)

1992-10-28

22

Exhaust gas recirculation system for an internal combustion engine  

Energy Technology Data Exchange (ETDEWEB)

An exhaust gas recirculation system for an internal combustion engine comprises an exhaust driven turbocharger having a low pressure turbine outlet in fluid communication with an exhaust gas conduit. The turbocharger also includes a low pressure compressor intake and a high pressure compressor outlet in communication with an intake air conduit. An exhaust gas recirculation conduit fluidly communicates with the exhaust gas conduit to divert a portion of exhaust gas to a low pressure exhaust gas recirculation branch extending between the exhaust gas recirculation conduit and an engine intake system for delivery of exhaust gas thereto. A high pressure exhaust gas recirculation branch extends between the exhaust gas recirculation conduit and the compressor intake and delivers exhaust gas to the compressor for mixing with a compressed intake charge for delivery to the intake system.

Wu, Ko-Jen

2013-05-21

23

Catalytic exhaust gas detoxification device. Katalytische Abgasentgiftungseinrichtung  

Energy Technology Data Exchange (ETDEWEB)

This is a catalytic exhaust gas detoxification device with a porous, particularly a honeycomb structure monolithic ceramic body with catalytic surface coating situated in a metal case with exhaust gas inlet and outlet openings, where the container jacket and the outside surface of the ceramic body may have a sealing feather pillow between them, where a centering ring is fixed to the outlet and inlet openings for the exhaust gas of the front of the ceramic body, to which an axial spring ring fixed to the case adheres.

Zachmann, A.; Wulftange, W.

1985-09-12

24

Coke-free dry reforming of model diesel fuel by a pulsed spark plasma at low temperatures using an exhaust gas recirculation (EGR) system  

International Nuclear Information System (INIS)

Dry reforming of diesel fuel, an endothermic reaction, is an attractive process for on-board hydrogen/syngas production to increase energy efficiency. For operating this dry reforming process in a vehicle, we can use the exhaust gas from an exhaust gas recirculation (EGR) system as a source of carbon dioxide. Catalytic dry reforming of heavy hydrocarbon is a very difficult reaction due to the high accumulation of carbon on the catalyst. Therefore, we attempted to use a non-equilibrium pulsed plasma for the dry reforming of model diesel fuel without a catalyst. We investigated dry reforming of model diesel fuel (n-dodecane) with a low-energy pulsed spark plasma, which is a kind of non-equilibrium plasma at a low temperature of 523 K. Through the reaction, we were able to obtain syngas (hydrogen and carbon monoxide) and a small amount of C2 hydrocarbon without coke formation at a ratio of CO2/Cfuel = 1.5 or higher. The reaction can be conducted at very low temperatures such as 523 K. Therefore, it is anticipated as a novel and effective process for on-board syngas production from diesel fuel using an EGR system.

2011-07-13

25

Exhaust gas recirculation system for internal combustion engine  

Energy Technology Data Exchange (ETDEWEB)

An impeller is disposed in an exhaust gas recirculation passage communicating between the exhaust passage and the intake passage of the engine. The impeller supplies part of the exhaust gas positively from the exhaust passage to the intake passage of the engine. The blowing device includes a blower which is driven electrically or mechanically.

Ushimura, S.

1983-02-15

26

Low temperature operation and exhaust emission  

Energy Technology Data Exchange (ETDEWEB)

Ambient temperature has the greatest effect on the exhaust emissions of internal combustion engines during the initial cold star and before the engine is fully warmed-up. Fuel evaporation is poor in a cold engine and the fuel-air mixture must be made richer to ensure that the engine weill start and be driveable. However, the combustion of a rich fuel-air mixture is incomplete because of the lack of oxygen, and the exhaust gases will contain an excessive amount of carbon monoxide (CO). The formation of nitrogen oxides (NO/sub x/) in a combustion engine is tied to high temperatures and oxygen concentrations. The conditions in a non-warmed engine using a rich fuel-air mixture are unfavourable for the formation of NO/sub x/ and the emission of NO/sub x/ may even diminish with falling ambient temperature. When the engine has reached its normal operating temperature the exhaust emissions are usually independent of the ambient temperature if the engine is equipped with intake air preheating that is sufficiently powerful. The reduction efficiency of a catalytic converter mainly depends on its operation temperature. Continuous operation at low temperatures may cause rapid poisoning of the converter. At low temperatures, carbon and other particles that do not burn collect on the active surface of the converter reducing its effectiveness.

Laurikko, J.

1987-01-01

27

Integrated exhaust gas recirculation and charge cooling system  

Science.gov (United States)

An intake system for an internal combustion engine comprises an exhaust driven turbocharger configured to deliver compressed intake charge, comprising exhaust gas from the exhaust system and ambient air, through an intake charge conduit and to cylinders of the internal combustion engine. An intake charge cooler is in fluid communication with the intake charge conduit. A cooling system, independent of the cooling system for the internal combustion engine, is in fluid communication with the intake charge cooler through a cooling system conduit. A coolant pump delivers a low temperature cooling medium from the cooling system to and through the intake charge cooler for the transfer of heat from the compressed intake charge thereto. A low temperature cooler receives the heated cooling medium through the cooling system conduit for the transfer or heat therefrom.

Wu, Ko-Jen

2013-12-10

28

Technique for radiation treatment of exhaust gas due to combustion  

International Nuclear Information System (INIS)

As the Japanese unique research in the field of preservation of environment, the technique to remove simultaneously sulphur dioxide and nitrogen oxides in exhaust gas using electron beam irradiation is noteworthy. This research was started by the experiment in the central research laboratory of Ebara Manufacturing Co., Ltd., in which it was found that the sulphur dioxide of initial concentration of 1,000 ppm was almost completely vanished when the exhaust gas of heavy oil combustion in a batch type vessel was irradiated for 9 minutes by electron beam. Based on this experiment, JAERI installed a continuous irradiation equipment with a large accelerator, and has investigated the effect of various parameters such as dose rate, irradiation temperature, total dose and agitation. This resulted in the remarkable finding that nitrogen oxides were also completely removed as well as sulphur dioxide when the exhaust gas containing both sulphur dioxide and nitrogen oxides was irradiated for a few seconds. In this case, if water of about 0.3% is added, removal rate of sulphur dioxide is greatly increased. The research group of University of Tokyo obtained other findings concerning removal rates. Then, after the pilot plant stage in Ebara Manufacturing Co., Ltd. from 1974, the test plant of exhaust gas treatment for a sintering machine, having the capacity of 3,000 Nm3/hr, has been constructed in Yawata Works of Nippon Steel Corp. This is now operating properly. (Wakatsuki, Y.)

1978-05-01

29

Interrelation of exhaust-gas constituents  

Science.gov (United States)

This report presents the results of an investigation conducted to determine the interrelation of the constituents of the exhaust gases of internal-combustion engines and the effect of engine performance on these relations. Six single-cylinder, liquid-cooled tests engines and one 9-cylinder radial air-cooled engine were tested. Various types of combustion chambers were used and the engines were operated at compression ratios from 5.1 to 7.0 using spark ignition and from 13.5 to 15.6 using compression ignition. The investigation covered a range of engine speeds from 1,500 to 2,100 r.p.m. The fuels used were two grades of aviation gasoline, auto diesel fuel, and laboratory diesel fuel. Power, friction, and fuel-consumption data were obtained from the single-cylinder engines at the same time that the exhaust-gas samples were collected.

Gerrish, Harold C; Voss, Fred

1938-01-01

30

PIXE analysis of exhaust gas from diesel engine  

International Nuclear Information System (INIS)

The variation of elemental concentrations in exhaust gas of a Diesel engine with the outputs was studied. Particulates in high temperature gas were collected on silica fiber filters and analyzed by PIXE method. Concentrations of S and V were nearly proportional to particulate masses and fuel consumption rates per discharging rates of exhaust gas respectively. While, concentrations of Fe and Mn were markedly increased together with engine outputs, and Mn/Fe ratios were nearly equal to those of the material of piston rings and the cylinder liner. Concentrations of the elements contained in lubricant, such as Ca and Mo, were also conspicuously increased with the outputs. It was shown that PIXE analysis is a useful tool for engine diagonostics owing to its high sensitive multi-elemental availability without chemical treatments. (author)

1986-01-01

31

Exhaust gas recirculation in a homogeneous charge compression ignition engine  

Energy Technology Data Exchange (ETDEWEB)

A homogeneous charge compression ignition engine operates by injecting liquid fuel directly in a combustion chamber, and mixing the fuel with recirculated exhaust and fresh air through an auto ignition condition of the fuel. The engine includes at least one turbocharger for extracting energy from the engine exhaust and using that energy to boost intake pressure of recirculated exhaust gas and fresh air. Elevated proportions of exhaust gas recirculated to the engine are attained by throttling the fresh air inlet supply. These elevated exhaust gas recirculation rates allow the HCCI engine to be operated at higher speeds and loads rendering the HCCI engine a more viable alternative to a conventional diesel engine.

Duffy, Kevin P. (Metamora, IL); Kieser, Andrew J. (Morton, IL); Rodman, Anthony (Chillicothe, IL); Liechty, Michael P. (Chillicothe, IL); Hergart, Carl-Anders (Peoria, IL); Hardy, William L. (Peoria, IL)

2008-05-27

32

Concepts of exhaust gas cleaning procedures; Konzepte der Abgasreinigungsverfahren  

Energy Technology Data Exchange (ETDEWEB)

The continuous forward projecting of the legal emissions requirements contributed to a persistent new development and further development within the area of exhaust gas processes. Within the last 10 to 15 years, further aspects such as optimization of means of production or energy as design characteristics of the exhaust gas cleaning systems came along. The report under consideration gives an overview of the exhaust gas cleaning procedures in Europe and shows when which procedure can be used. Furthermore, selection criteria and selection procedures of exhaust gas cleaning systems are shown.

Karpf, Rudi; Krueger, Tina; Conrad, Yannick [ete.a Ingenieurgesellschaft fuer Energie- und Umweltengineering und Beratung mbH, Lich (Germany)

2013-03-01

33

Inert Gas Generation Utilizing Diesel Exhaust  

Energy Technology Data Exchange (ETDEWEB)

The generation of inert gas from 60 KW diesel engine exhaust by catalytic reduction of O{sub 2} and NO{sub x} has been demonstrated. Measured O{sub 2} levels were < 10 V{sub ppm} and NO{sub x} levels were {approx} 0.1 V{sub ppm} over a wide range of equivalence ratios. Durability of the catalytic converter was demonstrated up to 200 hours operating time at two diesel engine load conditions. Effective catalyst operating range was stoichiometric to rich fuel/air ratios. Optimum operation is at stoichiometric fuel/air ratios to minimize CO emissions. Alternative converter designs are proposed to allow operation over the full diesel engine load range with essentially zero emissions of O{sub 2}, NO{sub x} and CO.

Osgerby, I. T.; Durilla, M.

1981-01-01

34

Biological exhaust gas cleaning; Biologische Abgasreinigung  

Energy Technology Data Exchange (ETDEWEB)

Exhaust gas containing high concentrations of acidifying constituents (organic nitrogen, sulfur and chlorine compounds) can be biologically cleaned in trickling filters. The problem of acidification of the water passing the filter in countercurrent is solved by continuous pH measurement and coupled automatic lye dosage; clogging of the trickling filter through excessive biomass accumulation is avoided by automatic control of water salinity as indicated by the water`s electrical conductivity. (SR) [Deutsch] Eine neuartige biologische Abgasreinigung - es handelt sich dabei um ein Bio-Tricklingfilter - reinigt Abgase mit hohen Konzentrationen an saeurenden Bestandteilen, zum Beispiel Stickstoff, Schwefel oder Chlor. Fuer diese Bestandteile bietet die Biofiltration keine Loesung, da das Filtermaterial versauert. Bei Bio-Tricklingfiltern bestand bisher das Problem, dass die sich schnell vermehrende Bakterienmasse das Filter verstopfte. Neue Mess- und Regeltechnik loest das Problem. (SR)

Anon.

1993-12-31

35

75 FR 82040 - Notice of Public Meeting on the International Maritime Organization Guidelines for Exhaust Gas...  

Science.gov (United States)

...guidelines for exhaust gas cleaning systems for marine engines...provide guidance for exhaust gas cleaning systems under MARPOL Annex...by the IMO for exhaust gas cleaning systems for marine engines...Go>>.'' Information on Services for Individuals With...

2010-12-29

36

Exhaust gas treatment system which can deal with dioxin; Dioxin taio hai gas shori  

Energy Technology Data Exchange (ETDEWEB)

This paper describes an exhaust gas treatment system which can deal with dioxin. A bag filter is a cloth filter to remove suspended solids. This filter can also remove gas components if reacting agents (including slaked lime) and absorbents (including activated carbon) are charged into a gas flow to perform reaction with gas components, and absorption and fixation thereof. In order to prevent secondary production of dioxin, the gas flow was quenched to below 150 deg C, activated carbon was charged, and the flow was filtered with bag filtration, where a removal rate of about 98% was attained. Dioxin can be decomposed by a catalyst as in removal of nitrogen oxides in exhaust gas, having attained a decomposition rate of 75%. An activated carbon column may also be used effectively. Using an electric dust collector increases dioxin concentration at the outlet, for which combined use of activated carbon at below 240 deg C is effective. Flying ash collected in the dust collector contains dioxin, hence it is heat treated at about 400 deg C so that dioxin is decomposed by more than 99% and made harmless. Basics of exhaust gas treatment are use of a temperature adjusting column, a bag filter, a catalyst column (or an activated carbon column), where removal auxiliaries may be used together with the bag filtration. Another realistic process is combination with low temperature operation of an electric dust collector. 10 refs., 7 figs., 4 tabs.

Nagai, K. [Hitachi Zosen Corp., Osaka (Japan)

1998-08-01

37

Development of Exhaust Gas Driven Absorption Chiller-Heater  

Science.gov (United States)

Waste heat from co-generation systems are usually recovered by hot water or steam, those are used to drive absorption refrigerators at cooling time, and those are used for heating via heat exchangers at heating time. However waste heat from micro gas turbines are discharged in the form of exhaust gas, it is simple that exhaust gas is directly supplied to absorption chiller-heaters. In the first report we studied cooling cycle, and this second paper, we evaluated various absorption heating cycles for exhaust gas driven absorption chiller-heaters, and adopted one of these cycles for the prototype machine. Also, we experimented with the prototype for wide range condition and got the heating characteristics. Based on the experimental data, we developed a simulation model of the static characteristics, and then studied how to increase the output by limited exhaust gas.

Inoue, Naoyuki; Endou, Tetsuya; Saito, Kiyoshi; Kawai, Sunao

38

Gas flow means for improving efficiency of exhaust hoods  

Energy Technology Data Exchange (ETDEWEB)

Apparatus for inhibiting the flow of contaminants in an exhaust enclosure toward an individual located adjacent an opening into the exhaust enclosure by providing a gas flow toward a source of contaminants from a position in front of an individual to urge said contaminants away from the individual toward a gas exit port. The apparatus comprises a gas mani-fold which may be worn by a person as a vest. The manifold has a series of gas outlets on a front face thereof facing away from the individual and toward the contaminants to thereby provide a flow of gas from the front of the individual toward the contaminants.

Gadgil, Ashok J. (El Cerrito, CA)

1994-01-01

39

Regenerable exhaust gas filter element for diesel engines  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a regenerable exhaust gas filter element for diesel engines. It comprises: an interlaced network of mullite crystals grown together to form a rigid porous body such that the soot carried by exhaust gas from a diesel engine flowing therethrough is trapped in the porous body, the network of mullite crystals being automatically interlaced and fused with one another to form the porous body.

Doty, P.A.; Moyer, J.R.; Hughes, N.N.

1992-03-24

40

IC ENGINE SUPERCHARGING AND EXHAUST GAS RECIRCULATION USING JET COMPRESSOR  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Supercharging is a process which is used to improve the performance of an engine by increasing the specific power output whereas exhaust gas recirculation reduces the NOx produced by engine because of supercharging. In a conventional engine, supercharger functions as a compressor for the forced induction of the charge taking mechanical power from the engine crankshaft. In this study, supercharging is achieved using a jet compressor. In the jet compressor, the exhaust gas is used as the motive...

Adhimoulame Kalaisselvane; Natarajan Alagumurthy; Krishnaraj Palaniradja; Selvaraj Gunasegarane, G.

2010-01-01

 
 
 
 
41

Exhaust gas recirculation control system for an internal combustion engine  

Energy Technology Data Exchange (ETDEWEB)

An exhaust gas recirculation control system for an internal combustion engine is described which comprises; an exhaust gas recirculation control valve for controlling a recirculation rate for exhaust gas to be mixed with intake air which is supplied to the internal combustion engine, an oxygen sensor disposed in an intake air passage downstream of the control valve to detect the concentration of oxygen in the intake air, a control means which compares the oxygen concentration detected by the oxygen sensor with a desired oxygen concentration previously determined depending on operational conditions of the engine and controls the degree of opening of the exhaust gas recirculation control valve so as to cancel the deviation between the detected oxygen concentration and the desired oxygen concentration, a detecting means for detecting the exhaust gas recirculation rate being zero to supply a signal to the control means on the basis of the detection, and a correcting means for correcting the corresponding relation between the output of the oxygen sensor and the detected oxygen concentration on the basis of the output of the oxygen sensor when the exhaust gas recirculation rate is zero.

Nishida, M.; Inoue, N.

1988-03-01

42

Low-pressure-ratio regenerative exhaust-heated gas turbine  

Energy Technology Data Exchange (ETDEWEB)

A design study of coal-burning gas-turbine engines using the exhaust-heated cycle and state-of-the-art components has been completed. In addition, some initial experiments on a type of rotary ceramic-matrix regenerator that would be used to transfer heat from the products of coal combustion in the hot turbine exhaust to the cool compressed air have been conducted. Highly favorable results have been obtained on all aspects on which definite conclusions could be drawn.

Tampe, L.A.; Frenkel, R.G.; Kowalick, D.J.; Nahatis, H.M.; Silverstein, S.M.; Wilson, D.G.

1991-01-01

43

Methane oxidation over noble metal catalysts as related to controlling natural gas vehicle exhaust emissions  

International Nuclear Information System (INIS)

Natural gas has considerable potential as an alternative automotive fuel. This paper reports on methane, the principal hydrocarbon species in natural-gas engine exhaust, which has extremely low photochemical reactivity but is a powerful greenhouse gas. Therefore, exhaust emissions of unburned methane from natural-gas vehicles are of particular concern. This laboratory reactor study evaluates noble metal catalysts for their potential in the catalytic removal of methane from natural-gas vehicle exhaust. Temperature run-up experiments show that the methane oxidation activity decreases in the order Pd/Al2O3 > Rh/Al2O3 > Pt/Al2O3. Also, for all the noble metal catalysts studied, methane conversion can be maximized by controlling the O2 concentration of the feedstream at a point somewhat rich (reducing) of stoichiometry

1991-08-25

44

Method for controlling exhaust gas heat recovery systems in vehicles  

Energy Technology Data Exchange (ETDEWEB)

A method of operating a vehicle including an engine, a transmission, an exhaust gas heat recovery (EGHR) heat exchanger, and an oil-to-water heat exchanger providing selective heat-exchange communication between the engine and transmission. The method includes controlling a two-way valve, which is configured to be set to one of an engine position and a transmission position. The engine position allows heat-exchange communication between the EGHR heat exchanger and the engine, but does not allow heat-exchange communication between the EGHR heat exchanger and the oil-to-water heat exchanger. The transmission position allows heat-exchange communication between the EGHR heat exchanger, the oil-to-water heat exchanger, and the engine. The method also includes monitoring an ambient air temperature and comparing the monitored ambient air temperature to a predetermined cold ambient temperature. If the monitored ambient air temperature is greater than the predetermined cold ambient temperature, the two-way valve is set to the transmission position.

Spohn, Brian L.; Claypole, George M.; Starr, Richard D

2013-06-11

45

Influence of temperature and hydrocarbons on removal of NOx and SO2 in a diesel exhaust gas activated by pulsed corona discharge  

International Nuclear Information System (INIS)

The influence of temperature and hydrocarbon additives on the NOx removal has been studied by numerical modelling and process experiments for a synthetic gas mixture consisting of N2, O2, H2O and CO2 in a pulsed corona reactor. The NO reduction of more than 99% was achieved at the energy cost of ?14 eV per NO molecule in the presence of 550 ppm C3H6 additive at T=393 K. The simulated results agree well with the experimental data measured in the NO and NOx removal and C2H4 and C3H6 decomposition. The C3H6 additive does not sufficiently suppress the conversion of SO2 to H2SO4. Within a limited framework of non-uniform modelling approach, the temperature effect on the streamer nature discharge has been taken into account. (author)

2002-07-21

46

Exhaust gas liquid heating system for internal combustion engines  

Energy Technology Data Exchange (ETDEWEB)

An exhaust gas liquid heating system is described for a two cylinder internal combustion engine, the system comprising a main heat exchanger spaced from an engine exhaust manifold and connected thereto by a pair of primary exhaust pipes which extend, in use, between exhaust ports of the engine and the main heat exchanger, the main heat exchanger comprising; inner and outer tubes forming a liquid jacket therebetween, inlet means whereby the primary exhaust pipes are respectively connected to communicate with the bore of the inner tube adjacent opposite ends thereof, outlet means whereby a secondary exhaust pipe is connected to communicate with the bore of the inner tube between the ends thereof and at a point substantially mid-way between the inlet means, and end caps forming a fluid seal over the ends of the tubes; and a serial liquid circuit including a holding tank, a pump for pumping liquid from the tank through a series of heat conducting coils wound around the primary and secondary exhaust pipes and in contact therewith, a liquid inlet on the main heat exchanger for providing communication between an end of the coils and the liquid jacket, and a liquid outlet on the man heat exchanger for providing communication between the liquid jacket and a tube extending to the holding tank, the liquid inlet and outlet being spaced apart along a portion of the length of the main heat exchanger being a similar portion over which the inlet and outlet means are spaced whereby exhaust gases passing along the inner tube between the inlet means and outlet means causes heat to be supplied to liquid passing along the liquid jacket between the liquid inlet and liquid outlet.

McConnell, P.J.

1986-06-10

47

Influence of light diesel fuel on diesel exhaust gas emission.  

Science.gov (United States)

Seven different diesel fuels were tested in order to investigate the influence of fuel properties on exhaust gas emission. A Volvo bus engine was used for 13-mode tests, and three buses (Volvo, Scania and Leyland) were used for measurements of particulate...

B. Frodl N. Ezerman F. Bak

1990-01-01

48

Test Program for High Efficiency Gas Turbine Exhaust Diffuser  

Energy Technology Data Exchange (ETDEWEB)

This research relates to improving the efficiency of flow in a turbine exhaust, and thus, that of the turbine and power plant. The Phase I SBIR project demonstrated the technical viability of “strutlets” to control stalls on a model diffuser strut. Strutlets are a novel flow-improving vane concept intended to improve the efficiency of flow in turbine exhausts. Strutlets can help reduce turbine back pressure, and incrementally improve turbine efficiency, increase power, and reduce greenhouse gas emmission. The long-term goal is a 0.5 percent improvement of each item, averaged over the US gas turbine fleet. The strutlets were tested in a physical scale model of a gas turbine exhaust diffuser. The test flow passage is a straight, annular diffuser with three sets of struts. At the end of Phase 1, the ability of strutlets to keep flow attached to struts was demonstrated, but the strutlet drag was too high for a net efficiency advantage. An independently sponsored followup project did develop a highly-modified low-drag strutlet. In combination with other flow improving vanes, complicance to the stated goals was demonstrated for for simple cycle power plants, and to most of the goals for combined cycle power plants using this particular exhaust geometry. Importantly, low frequency diffuser noise was reduced by 5 dB or more, compared to the baseline. Appolicability to other diffuser geometries is yet to be demonstrated.

Norris, Thomas R.

2009-12-31

49

Electron beam treatment of exhaust gas with high NOx concentration  

Science.gov (United States)

Simulated exhaust gases with a high NOx concentration, ranging from 200 to 1700 ppmv, were irradiated by an electron beam from an accelerator. In the first part of this study, only exhaust gases were treated. Low NOx removal efficiencies were obtained for high NOx concentrations, even with high irradiation doses applied. In the second part of study, gaseous ammonia or/and vapor ethanol were added to the exhaust gas before its inlet to the plasma reactor. These additions significantly enhanced the NOx removal efficiency. The synergistic effect of high SO2 concentration on NOx removal was observed. The combination of electron beam treatment with the introduction of the above additions and with the performance of irradiation under optimal parameters ensured high NOx removal efficiency without the application of a solid-state catalyst.

Licki, Janusz; Chmielewski, Andrzej G.; Pawelec, Andrzej; Zimek, Zbigniew; Witman, Sylwia

2014-05-01

50

Fiber metal acoustic material for gas turbine exhaust environments  

International Nuclear Information System (INIS)

FELTMETAL fiber metal acoustic materials function as broad band acoustic absorbers. Their acoustic energy absorbance occurs through viscous flow losses as sound waves pass through the tortuous pore structure of the material. Exhaust gas noise attenuation requirements are reviewed. Their selection process for higher performance materials is discussed. A new FELTMETAL fiber metal acoustic material has been designed for use in gas turbine auxiliary power unit exhaust environments without supplemental cooling. The physical and acoustic properties of mesh supported fiber metal acoustic medium FM 827 are discussed. Exposure testing was conducted under conditions which simulated auxiliary power unit operation. Weight gain and tensile strength data as a function of time of exposure at 6500C (12020F) are reported. Fabrication of components with fiber metal acoustic materials is easily accomplished using standard roll forming and gas tungsten arc welding practices

1989-01-01

51

Metallic materials for automotive exhaust gas catalyst supports  

Energy Technology Data Exchange (ETDEWEB)

Heat resistant iron-chromium-aluminium foils, suitable for manufacturing of automative exhaust gas catalyst supports, compared to the competing ceramic materials the metallic alloys exhibit high static and dynamic strength as much as in tension and bending as to thermal stresses and have a high thermal conductivity. Due to the low wall thickness of the foils also the space requirements of the catalysts are low. The most important criterion of heat resistant metallic materials in this application is sufficient resistance to oxidation combined with low cost. Therefore, in case of low to moderate requirements a low-alloyed material Aluchrom W (Fe-15Cr-4.5Al) will do the job. In case of more elevated temperatures, a higher alloyed material Aluchrom I RE (Fe-20Cr-5Al) with addition of rare earth elements has done service successfully in many applications. Reduced tendency to grain growth maintains high ductility of the materials even after long periods of service. In case of extreme requirements a material Aluchrom Y (Fe-20Cr-5Al with addition of 0.05% yttrium) is recommended. (orig./BWI).

Brill, U.; Heubner, U.

1988-09-01

52

Power plant including an exhaust gas recirculation system for injecting recirculated exhaust gases in the fuel and compressed air of a gas turbine engine  

Energy Technology Data Exchange (ETDEWEB)

A power plant is provided and includes a gas turbine engine having a combustor in which compressed gas and fuel are mixed and combusted, first and second supply lines respectively coupled to the combustor and respectively configured to supply the compressed gas and the fuel to the combustor and an exhaust gas recirculation (EGR) system to re-circulate exhaust gas produced by the gas turbine engine toward the combustor. The EGR system is coupled to the first and second supply lines and configured to combine first and second portions of the re-circulated exhaust gas with the compressed gas and the fuel at the first and second supply lines, respectively.

Anand, Ashok Kumar; Nagarjuna Reddy, Thirumala Reddy; Shaffer, Jason Brian; York, William David

2014-05-13

53

76 FR 58288 - International Maritime Organization Guidelines for Exhaust Gas Cleaning Systems for Marine...  

Science.gov (United States)

...Organization (IMO) for exhaust gas cleaning systems for marine engines...Guidelines for Exhaust Gas Cleaning Systems is also available in...regulation 14 and exhaust gas cleaning systems for marine engines...FR 3316). Information on Services for Individuals with...

2011-09-20

54

Admixed air for flue gas exhaust ventilator. Determination of the flow of admixed air for flue gas exhaust ventilators with due regard to the characteristic of the circuit  

Energy Technology Data Exchange (ETDEWEB)

A fluegas exhaust ventilator does require admixed air if the temperature of the fluegas to be exhausted surpasses the test and operation temperature of the exhaust ventilator in question. The determination of the least required flow of admixed air also has to consider the influence of the characteristic of the fluegas exhaust-and-admix network. This leads to a higher flow of admixed air, as results from former publications considering the mixing process only.

Epperlein, H.

1988-08-01

55

Temperature optimisation of a diesel engine using exhaust gas heat recovery and thermal energy storage (Diesel engine with thermal energy storage)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Modern automotive diesel engines are so energy efficient that they are heating up slowly and tend to run rather cold at subzero temperatures. The problem is especially severe in mail delivery operations where the average speed is low and the drive cycle includes plenty of idling. The problem is typically solved by adding a diesel fuelled additional engine heater which is used for the preheating of the engine during cold start and additional heating of the engine if the coo...

2009-01-01

56

Energy saving in crop de-hydration by recycling exhaust gas  

Energy Technology Data Exchange (ETDEWEB)

The article shows a demonstration project for de-hydration of grass used as cattle fodder, which was financially supported by the EC in its development and construction. By means of recycling the hot gases exhausting from the gas-driven dryer with a connected low-temperature evaporator (40 to 60/sup 0/C, avoidance of destruction of the protein in the grass to be dehydrated) in the dehydration process, the initial fuel need of 121 gas therms/t dried grass could be reduced to 98 gas therms/t dried grass. Some special characteristics of the energy-saving grass dehydration system are described by schemes and photos. (HWJ).

1986-01-01

57

Improvement of a gas turbine cycle without exhaust gases based on graphical exergy analysis  

Energy Technology Data Exchange (ETDEWEB)

This paper developed a gas turbine cycle with carbon dioxide as working fluid on the basis of a graphical exergy analysis (EUD - Energy Utilization Diagrams). Although the previous gas turbine cycle without exhaust gases has an advantage for recovering carbon dioxide, the EUD pointed out the problem and potential for improvement of this thermal system. For example, large exergy loss was found to occur in the heat exchange at low temperature. Furthermore, a saturation process into the gas turbine cycle without exhaust gases was introduced to utilize the low-level heat in the system. The improved system revealed the following characteristics: (a) thermal efficiency is increased from 43% to 49% (LHV); (b) the carbon dioxide exhaust in liquid form can be recovered; (c) there is low NO{sub x} formation due to no nitrogen in the combustor; (d) the water vapor in saturation process can be recovered; (e) the small amount of exhaust simplifies the removal of pollutants, like uncombusted fuel and other impurities. 7 refs., 5 figs., 1 tab.

Koren, B.; Jin, H.; Ishida, M. [Tokyo Institute of Technology, Yokohama (Japan). Research Lab. of Resources Utilization

1995-12-31

58

An Experimental Study of Different Effects of EGR Rates on The Performance And Exhaust Emissions of The Stratified Charge Piston Direct Injection Compressed Natural Gas Engine  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Exhaust Gas Recirculation (EGR) is one of the principal techniques used to control spark ignition NOX. A fraction of the exhaust gas is recycled through a control valve from the exhaust to the engine intake system. However, EGR has different effect on performance, combustion and emissions production that are difficult to distinguish such as increase of intake temperature, delay of Rate Of Heat Rrelease (ROHR), decrease of peak heat release, decrease in oxygen concentration et...

Wasiu, Saheed O.; Sulaiman, Shaharin A.; Aziz, A. Rashid A.

2011-01-01

59

Treating exhaust gas from a pressurized fluidized bed reaction system  

Energy Technology Data Exchange (ETDEWEB)

Hot gases from a pressurized fluidized bed reactor system are purified. Under superatmospheric pressure conditions hot exhaust gases are passed through a particle separator, forming a flitrate cake on the surface of the separator, and a reducing agent--such as an NO.sub.x reducing agent (like ammonia), is introduced into the exhaust gases just prior to or just after particle separation. The retention time of the introduced reducing agent is enhanced by providing a low gas velocity (e.g. about 1-20 cm/s) during passage of the gas through the filtrate cake while at superatmospheric pressure. Separation takes place within a distinct pressure vessel the interior of which is at a pressure of about 2-100 bar, and-introduction of reducing agent can take place at multiple locations (one associated with each filter element in the pressure vessel), or at one or more locations just prior to passage of clean gas out of the pressure vessel (typically passed to a turbine).

Isaksson, Juhani (Karhula, FI); Koskinen, Jari (Karhula, FI)

1995-01-01

60

Device for controlling an exhaust gas turbine. Vorrichtung zur Regelung einer Abgasturbine  

Energy Technology Data Exchange (ETDEWEB)

A shut-off device is provided here before the incoming ducts of the gas inlet housing of the turbine as the end of the exhaust manifold pipe system of an internal combustion engine connected to the exhaust gas turbine, so that at least one of the incoming ducts can be shut off. In such a version, the shut-off device can take the place of a special converter and the gas inlet housing of the exhaust gas turbine can remain unchanged.

Schacht, H.J.

1989-08-24

 
 
 
 
61

Laboratory Scale of Liquid Coal Fuel Combustion Process and Exhaust Gas Formation  

Directory of Open Access Journals (Sweden)

Full Text Available Problem statement: Much research of coal has been already undertaken to ascertain the possibilities of coal being used as substitute for heavy fuel oil in the transportation sector. The effects of using coal as transportation fuel to the environment must also be considered. This study will review several aspects of the coal oil combustion process including combustion behavior, flame stability, some emissions from exhaust gas; CO, NOx and the particulate matter in a well insulated laboratory scale furnace for more stable of combustion. Approach: New way for preparation for liquid coal oil steady combustion on a 2.75 m horizontal boiler with four annular segment tubes, a water jacket system and a system for measurement of water temperature inside was archived. Data was gained by applying liquid coal in the experiment. Detailed preparation and setting for steady combustion of coal oil and formation of the exhaust gas were discussed based on data sampling from four sample points in each centre of the angular tube segments. Results: Preparation for coal oil combustion is an important point in the successful of combustion. Heating coal fuel to than 100°C, heating the fuel line to the same temperature and providing enough air pressure for atomization of coal oil until 0.1 MPa allows coal fuel smoothly atomized in the semi gas phase. There was enough of air combustion via a blower with 4500 L min-1 of flow rate and a 24 L min-1 of water flow rate in the water jacket transforms the energy of the fuel to the heat. Uncolored of the exhaust gas and the physical inspection describes the completion of combustion. This result close-relates with the pollutants formation in the exhaust gas. Conclusion: By conducting a deep research process, there is a chance for the substitute of heavy fuel oil with liquid coal fuel with no special treatment needed in combustion process without ignoring the contribution of the combustion results as an environmental problem.

Kartika K. Hendratna

2010-01-01

62

Process and device for determining the exhaust gas feedback rate for internal combustion engines. Verfahren und Vorrichtung zur Bestimmung der Abgasrueckfuehrrate (ARF-R) bei Brennkraftmaschinen  

Energy Technology Data Exchange (ETDEWEB)

This is a process and device for determining the exhaust gas feedback rate for internal combustion engines (Diesel engines), where, in order to control the quantity of exhaust gas fed back to the suction air area, a setting member in the exhaust gas feedback pipe is moved by a controller, to which the measured exhaust gas temperature is fed as the load signal for the internal combustion engine. Either the actual value of the exhaust gas feedback rate measured in the suction area of the internal combustion engine or a reference differential temperature obtained by measuring the mass of air sucked in and the speed, is used as the comparative value of the controller.

Ripper, W.; Straubel, M.; Wessel, W.

1983-12-08

63

Exhaust gas recirculation in medium speed gas engines; Abgasrueckfuehrung im mittelschnell laufenden Gasmotor  

Energy Technology Data Exchange (ETDEWEB)

In the project presented in this article by WTZ Rosslau gGmbH, the impact of cooled exhaust gas recirculation was tested on a single-cylinder gas engine in lean mixture conditions. Special focus was on the basic engine parameters, such as thermal efficiency, brake mean effective pressure (BMEP), knocking behaviour and a reduction in the emission of unburned hydrocarbon (THC). (orig.)

Tschalamoff, T. [WTZ Rosslau gGmbH (Germany)

2004-11-01

64

Exhaust Gas Recirculation in Gas Turbines for Reduction of CO2 Emissions; Combustion Testing with Focus on Stability and Emissions  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Exhaust gas recirculation can be applied with the intention of reducing CO2 emissions. When a fraction of the exhaust gas is injected in the entry of a gas turbine, the amount of CO2 in the exhaust gas not being recirculated will be higher and less complicated to capture. However, with this change in combustion air composition, especially the reduced concentration of oxygen, the combustion process will be affected. The lower oxygen concentration decreases the stability and the increased amoun...

Røkke, Petter E.; Hustad, Johan E.

2005-01-01

65

Solid electrolyte exhaust gas sensor with increased NO/sub x/ sensitivity  

Energy Technology Data Exchange (ETDEWEB)

A solid electrolyte exhaust gas oxygen responsive sensor having a platinum exhaust gas electrode and a porous ceramic coating on the electrode is disclosed. The porous ceramic coating contains rhodium for making the sensor also responsive to NO/sub x/. In a specific example, rhodium permeates a gamma alumina porous overcoat on a sputtered platinum film serving as an exhaust gas electrode on a zirconia solid electrolyte member.

Sinkevitch, R.M.

1980-04-22

66

Thermodynamic analysis of combined open-cycle-twin-shaft gas turbine (Brayton cycle) and exhaust gas operated absorption refrigeration unit  

Energy Technology Data Exchange (ETDEWEB)

The exhaust gases of a gas turbine carry a significant amount of thermal energy that is usually expelled to the atmosphere without taking any further part in the power generation processes. The low grade thermal energy can however be put to beneficial use. This paper explores the utilisation of the exhaust gases of an open-cycle-twin-shaft gas turbine. An air standard cycle is assumed for the gas turbine, first with the aid of thermodynamic laws the specific network and the efficiency of the cycle as a function of temperature ratio and pressure ratio of the cycle are calculated, and the realistic bounds placed on the cycle by the thermodynamic analysis is shown. Then the temperature of the exhaust gases and the heat that can be put to benefit for precooling in terms of the temperature ratio and pressure ratio of the cycle are determined. The specific network and efficiency of a precooled cycle have been calculated and compared to conventional systems. (author)

Mostafavi, M. [Shiraz University (Iran, Islamic Republic of); Alaktiwi, A. [Academy of Maritime Studies, Tripoli (Libyan Arab Jamahiriya); Agnew, B. [University of Newcastle upon Tyne (United Kingdom). Dept. of Mechanical, Materials and Manufacturing Engineering

1998-09-01

67

Exhaust Gas Recirculation in Gas Turbines for Reduction of CO2 Emissions; Combustion Testing with Focus on Stability and Emissions  

Directory of Open Access Journals (Sweden)

Full Text Available Exhaust gas recirculation can be applied with the intention of reducing CO2 emissions. When a fraction of the exhaust gas is injected in the entry of a gas turbine, the amount of CO2 in the exhaust gas not being recirculated will be higher and less complicated to capture. However, with this change in combustion air composition, especially the reduced concentration of oxygen, the combustion process will be affected. The lower oxygen concentration decreases the stability and the increased amount of CO2, H2O and N2 will decrease the combustion temperature and thus, the NOx emissions. Testing has been performed on a 65 kW gas turbine combustor, to investigate the effect of adding N2, CO2 and O2 in the combustion process, with focus on stability and emissions of NOx. Results show that adding N2 and CO2 decreases the NOx emissions, whereas O2 addition increases the NOx emissions. The tests have been performed both in a diffusion flame (pilot burner and a premixed flame (main burner, and for additives being injected with the fuel or with the air stream. Addition into the fuel stream is proven to affect the NOx emissions the most. The stability limits of the flames are indicated with respect to mass-based additive-to-fuel ratios.

Johan E. Hustad

2005-12-01

68

An experimental study on the effects of exhaust gas on spruce (Picea abies L. Karst.)  

Energy Technology Data Exchange (ETDEWEB)

Motor vehicle exhausts are significant contributors to air pollution. Besides fine particles and inorganic gases, like CO, SO{sub 2} and NO{sub x}, exhaust gas contains a large group of aromatic hydrocarbon compounds, many of which are phytotoxic. In field studies, exhausts are found to have both direct and indirect harmful effects on roadside plants. However, only few experimental studies have been made about the effects of exhaust gas emissions on coniferous trees. The aim of this study was to survey the effects of exhausts on spruce (Picea abies L. Karst.) in standardized conditions. The concentrations of major exhaust gas components in the chamber atmosphere were detected simultaneously. The effects of exhaust on epistomatal waxes of first-year spruce needles are described. (author)

Hautala, E.L.; Holopainen, J.; Kaerenlampi, L. [Kuopio Univ. (Finland). Dept. of Ecology and Environmental Science; Surakka, J.; Ruuskanen, J. [Kuopio Univ. (Finland). Dept. of Environmental Sciences

1995-12-31

69

Direct and Indirect Applications of Dielectric Barrier Discharge Plasma to Catalytic Reduction of Nitrogen Oxides from Exhaust Gas  

International Nuclear Information System (INIS)

Dielectric barrier discharge (DBD) plasma was utilized to oxidize NO contained in the exhaust gas to NO2, ultimately improve the selective catalytic reduction of nitrogen oxides (NOx). In the one case, DBD was created directly in the exhaust gas (direct application), and in the an other case, ozone produced by DBD was injected into the exhaust gas (indirect application). A comparative study between such direct and indirect applications of DBD plasma was made in terms of the NOx removal efficiency and the energy consumption. The NO2 content in the exhaust gas was changed by the voltage applied to the DBD device (for direct application) or by the amount of ozone added to the exhaust gas (for indirect application). In both cases, NO was easily oxidized to NO2, and the change in NO2 content largely affected the NOx removal performance of the catalytic reactor placed downstream, where both NO and NO2 were reduced to N2 in the presence of ammonia as the reducing agent. The experiments were primarily concerned with the effect of reaction temperature on the catalytic NOx reduction at various NO2 contents. The direct and indirect applications of DBD were found to remarkably improve the catalytic NOx reduction, especially at low temperatures

2006-03-01

70

Engine exhaust particulate and gas phase contributions to vascular toxicity.  

Science.gov (United States)

Abstract Cardiovascular health effects of near-roadway pollution appear more substantial than other sources of air pollution. The underlying cause of this phenomenon may simply be concentration-related, but the possibility remains that gases and particulate matter (PM) may physically interact and further enhance systemic vascular toxicity. To test this, we utilized a common hypercholesterolemic mouse model (Apolipoprotein E-null) exposed to mixed vehicle emission (MVE; combined gasoline and diesel exhausts) for 6?h/d?×?50?d, with additional permutations of removing PM by filtration and also removing gaseous species from PM by denudation. Several vascular bioassays, including matrix metalloproteinase-9 protein, 3-nitrotyrosine and plasma-induced vasodilatory impairments, highlighted that the whole emissions, containing both particulate and gaseous components, was collectively more potent than MVE-derived PM or gas mixtures, alone. Thus, we conclude that inhalation of fresh whole emissions induce greater systemic vascular toxicity than either the particulate or gas phase alone. These findings lend credence to the hypothesis that the near-roadway environment may have a more focused public health impact due to gas-particle interactions. PMID:24730681

Campen, Matthew; Robertson, Sarah; Lund, Amie; Lucero, Joann; McDonald, Jacob

2014-05-01

71

Cross-flow type internal combustion engine with a small sized exhaust gas recirculating system  

Energy Technology Data Exchange (ETDEWEB)

A cylinder head of a cross-flow type internal combustion engine is formed with a through hole or a groove which is associated with an exhaust gas recirculating system to simplify the exhaust gas recirculating system and simultaneously to make it small.

Hayashi, Y.; Kamino, H.; Ohnishi, A.; Waku, M.

1980-09-09

72

Performance of humid air turbine with exhaust gas expanded to below ambient pressure based on microturbine  

Energy Technology Data Exchange (ETDEWEB)

A new type of HAT cycle comprising HAT and Inverted Brayton cycles, named BAHAT in this paper, is proposed to enhance the microturbine's performance. By adding an exhaust compressor after flue gas condenser, the gas expander expands to a pressure lower than ambient. Simulation and parameter optimization results show that the electricity efficiency and specific work of BAHAT are about 2 percentage points and 20% higher than that of HAT cycle respectively when turbine inlet temperature is 950 C. The working pressure of aftercooler, humidifier and turbine hot section is only about 0.4 MPa though the optimal total pressure ratio is about 9-10. The drops of compression work and outlet water temperature of humidifier are considered the main factors to enhance BAHAT's efficiency. In addition, the exhaust compressor inlet gas temperature affects BAHAT's efficiency and water recovery ratio apparently. It is also shown that it is easy to achieve water self-support for BAHAT, mixing makeup water to the water loop before entering economizer shows the best thermodynamic performance, and air leakage to the bottom cycle influences both efficiency and water recovery ratio of BAHAT. (author)

Kuifang Wan; Jing Wang [Key Laboratory of Advanced Energy and Power, Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Shijie Zhang; Yunhan Xiao [Key Laboratory of Advanced Energy and Power, Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190 (China)

2010-11-15

73

Performance of humid air turbine with exhaust gas expanded to below ambient pressure based on microturbine  

International Nuclear Information System (INIS)

A new type of HAT cycle comprising HAT and Inverted Brayton cycles, named BAHAT in this paper, is proposed to enhance the microturbine's performance. By adding an exhaust compressor after flue gas condenser, the gas expander expands to a pressure lower than ambient. Simulation and parameter optimization results show that the electricity efficiency and specific work of BAHAT are about 2 percentage points and 20% higher than that of HAT cycle respectively when turbine inlet temperature is 950 deg. C. The working pressure of aftercooler, humidifier and turbine hot section is only about 0.4 MPa though the optimal total pressure ratio is about 9-10. The drops of compression work and outlet water temperature of humidifier are considered the main factors to enhance BAHAT's efficiency. In addition, the exhaust compressor inlet gas temperature affects BAHAT's efficiency and water recovery ratio apparently. It is also shown that it is easy to achieve water self-support for BAHAT, mixing makeup water to the water loop before entering economizer shows the best thermodynamic performance, and air leakage to the bottom cycle influences both efficiency and water recovery ratio of BAHAT.

2010-11-01

74

Performance of humid air turbine with exhaust gas expanded to below ambient pressure based on microturbine  

Energy Technology Data Exchange (ETDEWEB)

A new type of HAT cycle comprising HAT and Inverted Brayton cycles, named BAHAT in this paper, is proposed to enhance the microturbine's performance. By adding an exhaust compressor after flue gas condenser, the gas expander expands to a pressure lower than ambient. Simulation and parameter optimization results show that the electricity efficiency and specific work of BAHAT are about 2 percentage points and 20% higher than that of HAT cycle respectively when turbine inlet temperature is 950 deg. C. The working pressure of aftercooler, humidifier and turbine hot section is only about 0.4 MPa though the optimal total pressure ratio is about 9-10. The drops of compression work and outlet water temperature of humidifier are considered the main factors to enhance BAHAT's efficiency. In addition, the exhaust compressor inlet gas temperature affects BAHAT's efficiency and water recovery ratio apparently. It is also shown that it is easy to achieve water self-support for BAHAT, mixing makeup water to the water loop before entering economizer shows the best thermodynamic performance, and air leakage to the bottom cycle influences both efficiency and water recovery ratio of BAHAT.

Wan Kuifang [Key Laboratory of Advanced Energy and Power, Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Zhang Shijie, E-mail: zhangsj@mail.etp.ac.c [Key Laboratory of Advanced Energy and Power, Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190 (China); Wang Jing [Key Laboratory of Advanced Energy and Power, Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Xiao Yunhan [Key Laboratory of Advanced Energy and Power, Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190 (China)

2010-11-15

75

An efficient venturi scrubber system to remove submicron particles in exhaust gas.  

Science.gov (United States)

An efficient venturi scrubber system making use of heterogeneous nucleation and condensational growth of particles was designed and tested to remove fine particles from the exhaust of a local scrubber where residual SiH4 gas was abated and lots of fine SiO2 particles were generated. In front of the venturi scrubber, normal-temperature fine-water mist mixes with high-temperature exhaust gas to cool it to the saturation temperature, allowing submicron particles to grow into micron sizes. The grown particles are then scrubbed efficiently in the venturi scrubber. Test results show that the present venturi scrubber system is effective for removing submicron particles. For SiO2 particles greater than 0.1microm, the removal efficiency is greater than 80-90%, depending on particle concentration. The corresponding pressure drop is relatively low. For example, the pressure drop of the venturi scrubber is approximately 15.4 +/- 2.4 cm H2O when the liquid-to-gas ratio is 1.50 L/m3. A theoretical calculation has been conducted to simulate particle growth process and the removal efficiency of the venturi scrubber. The theoretical results agree with the experimental data reasonably well when SiO2 particle diameter is greater than 0.1 microm. PMID:15828674

Tsai, Chuen-Jinn; Lin, Chia-Hung; Wang, Yu-Min; Hunag, Cheng-Hsiung; Li, Shou-Nan; Wu, Zong-Xue; Wang, Feng-Cai

2005-03-01

76

Removal of methane from compressed natural gas fueled vehicle exhaust  

International Nuclear Information System (INIS)

The objective of this paper is to investigate the modes of methane (CH4) removal from simulated compressed natural gas (CNG) fueled vehicle exhaust under net oxidizing, net reducing, and stoichiometric conditions. Model reaction studies were conducted. The results suggest that the oxidation of methane with oxygen contributes to the removal of methane under net oxidizing conditions. In contrast, the oxidation of methane with oxygen as well as nitric oxide contributes to its removal under net reducing conditions. The steam reforming reaction does not significantly contribute to the removal of methane. The methane conversions under net reducing conditions are higher than those observed under net oxidizing conditions. The study shows that the presence of carbon monoxide in the feed gas leads to a gradual decrease in the methane conversion with increasing redox ratio, under net oxidizing conditions. a minimum in methane conversion is observed at a redox ratio of 0. 8. The higher activity for the methane-oxygen reaction resulting from a lowering in the overall oxidation state of palladium and the contribution of the methane-nitric oxide reaction toward the removal of CH4 appear to account for the higher CH4 conversions observed under net reducing conditions

1992-11-01

77

Effects of Exhaust Gas Recirculation on SI Engines at Wide Open Throttle  

Science.gov (United States)

Exhaust gas recirculation, a charge dilution technique, has proven to be an effective method of reducing NOx emissions and fuel consumption of spark ignition engines. Wide open throttle operation also increases overall engine efficiency by reducing the pumping losses caused by throttling. In this study, the emissions and fuel economy benefits of exhaust gas recirculation (EGR) at wide open throttle conditions were quantified using a 2.4L port-injected engine. Engine performance and emissions data were recorded as the percentage of EGR in the intake charge was increased from zero to just above thirty percent (the EGR limit). This EGR percentage, in-cylinder pressure measurements, and the temperatures and pressures of the intake and exhaust were all recorded to ensure stable operating conditions. These tests were performed with a stoichiometric air-fuel ratio at a constant speed of 2000 rpm at wide open throttle. The variation of brake specific fuel consumption and emissions (in particular NOx) with increasing EGR percentages was analyzed.

Bronson, Sydney; Puzinauskas, Paulius

2011-11-01

78

Temperature monitoring of vehicle engine exhaust gases under vibration condition using optical fibre temperature sensor systems  

International Nuclear Information System (INIS)

Two optical approaches, comprising and contracting both the fluorescence decay lifetime and the fibre Bragg grating (FBG) methods, were developed and evaluated for temperature monitoring of exhaust gases for use on a vehicle engine. The FBGs used in the system were written into specially designed Bi-Ge co-doped photosensitive fibres, to enable them to sustain high temperatures to over 8000C, which is far beyond that of FBGs written into most commercial photosensitive fibres. The sensors were subjected to a range of vibration tests, as a part of an optical exhaust monitoring network under development, and results from the test carried out are reported

2006-07-01

79

Thermodynamic analysis of combined open-cycle-twin-shaft gas turbine (Brayton cycle) and exhaust gas operated absorption refrigeration unit  

Energy Technology Data Exchange (ETDEWEB)

This paper explores the utilisation of the exhaust gases of an open-cycle-twin-shaft gas turbine. An air standard cycle is assumed for the gas turbine, first with the aid of thermodynamics laws the specific network and the efficiency of the cycle as a function of temperature ratio and pressure ratio of the cycle are calculated, and the realistic bounds placed on the cycle by the thermodynamic analysis is shown. It has been concluded that the precooling has a marked effect on the specific network and efficiency at low temperature ratio. Also without increasing the maximum cycle temperature the precooled cycle can work at a higher compressor pressure ratio and at higher temperature ratio. (author)

Mostafavi, M. [Shiraz Univ., Shiraz (Iran, Islamic Republic of); Alaktiwi, A. [Acadimic of Maritime Studies, Tripoli (Libyan Arab Jamahiriya); Agnew, B. [Newcastle upon Tyne Univ., Mechanical, Materials and Manufacturing Engineering Dept., Newcastle upon Tyne (United Kingdom)

1997-08-01

80

Three-dimensional approach to exhaust gas energy analysis  

Science.gov (United States)

Presented work is based on an extensive CFD simulation of the exhaust stroke of a single-cylinder four-stroke internal combustion engine with the exhaust manifold attached. Since the dynamics of the exhaust flow are extremely 3D, an innovative approach to calculate the local entropy generation is developed and implemented in the discussed 3D numerical model. It allows temporal and spatial determination of critical regions and periods of entropy generation in the process with objective to reduce it.

Sekav?nik, M.; Ogorevc, T.; Katrašnik, T.; Rodman-Oprešnik, S.

2012-06-01

 
 
 
 
81

Data reduction and evaluation procedures. [concerning exhaust gas analysis  

Science.gov (United States)

The computational procedures that are involved in exhaust emissions data reduction and the use of these computational procedures for determining the quality of the data that is obtained from exhaust measurements were considered. Four problem areas were calculated: (1) the various methods for performing the carbon balance, (2) the method for calculating water correction factors, (3) the method for calculating the exhaust molecular weight, and (4) assessing the quality of the data.

Mirsky, W.

1976-01-01

82

Platform for a Hydrocarbon Exhaust Gas Sensor Utilizing a Pumping Cell and a Conductometric Sensor  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Very often, high-temperature operated gas sensors are cross-sensitive to oxygen and/or they cannot be operated in oxygen-deficient (rich) atmospheres. For instance, some metal oxides like Ga2O3 or doped SrTiO3 are excellent materials for conductometric hydrocarbon detection in the rough atmosphere of automotive exhausts, but have to be operated preferably at a constant oxygen concentration. We propose a modular sensor platform that combines a conductometric two-sensor-setup with an electroche...

2009-01-01

83

Dual-purpose power plants, experiences with exhaust gas purification plants  

International Nuclear Information System (INIS)

From 1984 to 1988, the research and development project ''pollutant reduction for exhaust gases from heat production systems'' sponsored by the Federal Ministry of Research and Technology (BMFT) has been carried out by TUeV in Bavaria. This project was to show the state of exhaust gas technology for small and medium-sized plants (boilers and motoric heat generators). When publishing the final report, no positive balance could be given. Based on the results, the succession project ''Exhaust gas purification plants in field test'' (ARIF) has been started. This project has the following objectives: -Measuring technical investigation of the exhaust gas purification of motoric driven heat generator systems in field test. - Suitability of hand measuring devices for emissions for a discontinuous control of the exhaust gas purification plat by the operator. - Control of new methods regarding pollutant reduction for motoric and conventional heat generators. (orig.)

1993-03-24

84

Development of exhaust gas treatment technologies for environment protection  

International Nuclear Information System (INIS)

Full text: The emission of carbon dioxide (CO2) and other pollutants which result from burning fossil fuels has been identified as the major contributor to global warming and climate change. However, for the immediate term over the next 10 - 20 years at least, the world will continue to rely on fossil fuels as the source of primary energy. The challenge for the fossil fuel industry is to find cost-effective solutions that will reduce the release of CO2 and other pollutants into the atmosphere. The focus of this paper is on the ability to treat the exhaust gas from fossil fuel power plants in order to capture and store the CO2 and remove other pollutants such as SOx and NOx which are released in the atmosphere. In summary, capture/separation costs represent the largest financial impediment for this types of plants. Hence, efficient, cost-effective capture/separation technologies will need to be developed in order to allow their large-scale use. (authors)

2006-10-25

85

Carbon Dioxide Emission Analysis of Chilled Water Production by Using Gas Turbine Exhaust Heat  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Carbon dioxide from exhaust heat emission is one of the major contributorsto the environmental pollutant in power generation plants. This problem could be addressed if the emitted exhaust heat is recovered. In cogeneration plant, the exhaust heat from the gas turbine is used to generate steam usingHeat Recovery Steam Generator. The steam from Heat Recovery Steam Generator is then used for chilled water generation in Steam Absorption Chillers by absorption process. This study analyzed the tota...

2013-01-01

86

Use of exhaust gas recirculation as a control approach for thermoacoustic instabilities  

Energy Technology Data Exchange (ETDEWEB)

Investigation into exhaust gas recirculation (EGR) as a method for reducing costs of postcombustion carbon capture in gas turbine systems reveals that EGR offers potential applications as a control strategy for thermoacoustic instabilities. Introduction of EGR allows semi-independent variation of the operating parameter of flame temperature and characteristic flame length scales, known to play a primary role in the phase of the thermoacoustic coupling mechanism. Measurements were made showing the ability of EGR to reduce the amplitude of thermoacoustic oscillations over a range of operating conditions in a laboratory scale, swirled dump combustor, without affecting the flame temperature. Theoretical analysis was also performed to investigate the limitations on the ability of this approach to influence dynamics.

Ranalli, J.; Ferguson, D.

2011-10-09

87

Design of a DBD System for On-Board Treatment of the Exhaust Gas  

Energy Technology Data Exchange (ETDEWEB)

This study is a part of the investigation of the diesel engine exhaust cleaning processes concerning a design of a compact, low power dielectric barrier discharge (DBD) system for on-board treatment of the exhaust gas in combination with a catalyst. The activated gas molecules and reduction agents which are produced by the discharge make the operation of the catalyst more efficient. The effect of the discharge frequency, power and geometry on the gas composition is described in our previous publication.

Joa, S. B.; Plaksin, Vadim Yu; Penkov, Oteksiy V.; Ruddy, F. H.; Dullo, A. R.; Lee, Heon Ju [Jeju National University, Jeju (Korea, Republic of)

2009-05-15

88

Design of a DBD System for On-Board Treatment of the Exhaust Gas  

International Nuclear Information System (INIS)

This study is a part of the investigation of the diesel engine exhaust cleaning processes concerning a design of a compact, low power dielectric barrier discharge (DBD) system for on-board treatment of the exhaust gas in combination with a catalyst. The activated gas molecules and reduction agents which are produced by the discharge make the operation of the catalyst more efficient. The effect of the discharge frequency, power and geometry on the gas composition is described in our previous publication

2009-05-01

89

Mechatronic exhaust gas recirculation valve for commercial vehicle applications; Mechatronisches Abgasrueckfuehrventil fuer Nutzfahrzeug-Anwendungen  

Energy Technology Data Exchange (ETDEWEB)

The emission optimization of commercial diesel engines, both on-highway and off-highway, will need further measures to meet the requirements of worldwide strengthening emission laws. In addition to exhaust gas aftertreatment systems also the external exhaust gas recirculation established in passenger cars with diesel engines offers substantial potential for lowering the engine-out emissions of vehicle engines. To this effect, Pierburg GmbH in Neuss, Germany, developed a completely electrically actuated exhaust gas recirculation system for heavy-duty applications. (orig.)

Toennesmann, Andres; Dismon, Heinrich; Nowak, Martin; Lappan, Rolf; Voigtlaender, Karsten [Pierburg GmbH, Neuss (Germany)

2008-09-15

90

Evaluating tractor performance and exhaust gas emissions using biodiesel from cotton seed oil  

International Nuclear Information System (INIS)

Alternative fuels for diesel engines, such as biodiesel, have attracted much attention recently due to increasing fuel prices and the imperative to reduce emissions. The exhaust gas emissions from tractors and other agricultural machinery make a significant contribution to these emissions. The use of biodiesel in internal combustion engines (ICE) has been reported to give comparable performance to conventional diesel (CD), but with generally lower emissions. There is however, contradictory evidence of NO emissions being both higher and lower from the use of biodiesel. In this work, agriculture tractor engine performance and its emission using both CD and biodiesel from cotton seed oil (CSO-B20) mixed at a 20% blend ration has been evaluated and compared. The PTO test results showed comparable exhaust emissions between CD and CSO-B20. However, the use of CSO-B20 led to reductions in the thermal efficiency and exhaust temperature and an increase in the brake specific fuel consumption (BSFC), when compared to CD.

2012-09-18

91

Evaluating tractor performance and exhaust gas emissions using biodiesel from cotton seed oil  

Science.gov (United States)

Alternative fuels for diesel engines, such as biodiesel, have attracted much attention recently due to increasing fuel prices and the imperative to reduce emissions. The exhaust gas emissions from tractors and other agricultural machinery make a significant contribution to these emissions. The use of biodiesel in internal combustion engines (ICE) has been reported to give comparable performance to conventional diesel (CD), but with generally lower emissions. There is however, contradictory evidence of NO emissions being both higher and lower from the use of biodiesel. In this work, agriculture tractor engine performance and its emission using both CD and biodiesel from cotton seed oil (CSO-B20) mixed at a 20% blend ration has been evaluated and compared. The PTO test results showed comparable exhaust emissions between CD and CSO-B20. However, the use of CSO-B20 led to reductions in the thermal efficiency and exhaust temperature and an increase in the brake specific fuel consumption (BSFC), when compared to CD.

Al-lwayzy, Saddam H.; Yusaf, Talal; Jensen, Troy

2012-09-01

92

Investigation of exhaust gas recirculation in otto- and diesel engines; Untersuchung der Abgasrueckfuehrung an Otto- und Dieselmotor  

Energy Technology Data Exchange (ETDEWEB)

Exhaust gas recirculation within the engine has become a tried and tested method of complying with future nitric oxide values in the exhaust of otto- and diesel engines. The authors look at the relevant parameters for the formation of nitric oxide - available oxygen and peak temperatures and show exhaust gas recirculation in an indealised circular process in order to assess the qualitative influence on engine process parameters. Methods of determining the exhaust gas recirculation rate are discussed. Examples are given to illustrate the main criteria of exhaust gas recirculation - throughput, reproduceability, equal distribution and dynamic response behaviour. A new Clean-EGR-system (exhaust gas recirculation from 4 to 1) which uses a continuous soot filter (CRT-system) is investigated. The system is used in a CV-engine with the aim of undercutting the max. values of Euro IV and V without influencing fuel consumption. (orig.) [German] Sowohl bei ottomotorischen Mager- und Direkteinspritzungskonzepten als auch in der Dieselmotorenentwicklung wird die innermotorische Massnahme Abgasrueckfuehrung als geeignetes Mittel zur Erreichung der zukuenftigen Stickoxid-Abgasgrenzwerte verfolgt. Zur qualitativen Untersuchung der Einfluesse auf die motorischen Prozessgroessen wird im Hinblick auf die relevanten Groessen der Stickoxidbildung - Sauerstoffangebot und Spitzentemperatur - die Abgasrueckfuehrung im idealisierten Kreisprozess dargestellt. Ferner werden Methoden zur Bestimmung der Abgasrueckfuehrrate diskutiert. Die Hauptkriterien der Realisierung einer Abgasrueckfuehrung - Durchsatz, Reproduzierbarkeit, Gleichverteilung und dynamisches Ansprechverhalten - werden an ausgefuehrten Beispielen eroertert. Es wird ein neuartiges Clean-EGR-System (Abgasrueckfuehrung von 4 nach 1) mit einem kontinuierlich arbeitenden Russfilter (CRT-System) an einem Nutzfahrzeug-Motor hinsichtlich der kraftstoffverbrauchsneutralen Unterschreitung der Grenzwerte der Stufen Euro IV und Euro V untersucht. (orig.)

Wagner, C.

1999-07-01

93

Gasoline Composition and Vehicle Exhaust Gas Polynuclear Aromatic Content.  

Science.gov (United States)

Vehicle emission control systems, fuel composition, and fuel-derived engine deposits have been studied as variables affecting the exhaust emissions of eleven species of polynuclear aromatics (PNA) and phenols. Both deposit-formation fuels and various emis...

G. P. Gross

1972-01-01

94

Evaluation of SI engine exhaust gas emissions upstream and downstream of the catalytic converter  

International Nuclear Information System (INIS)

The conversion efficiency of a catalytic converter, mounted on a vehicle equipped with a 2.8 l spark ignition engine, was evaluated under steady state operating conditions. The inlet and outlet chemical species concentration, temperature and air fuel ratio (A/F) were measured as a function of the brake mean effective pressure (BMEP) and engine speed (rpm). Oil temperature, coolant temperature, brake power and spark advance were also monitored. In parallel, a mathematical model for the catalytic converter has been developed. The main inputs of the model are the temperature, flow rate, chemical species mass flow and local A/F ratio as measured at the catalyst inlet section. The main conclusions are: (i) the exhaust gas and substrate wall temperatures at the catalyst outlet increase with BMEP and rpm; (ii) the HC conversion efficiency increases with the value of BMEP up to a maximum beyond which it decreases; (iii) the CO conversion efficiencies typically increase with BMEP; (iv) the NO x conversion efficiency remains nearly constant regardless of BMEP and rpm; (v) except for idle, the NO x conversion efficiency is typically the highest, followed in turn by the CO and HC conversion efficiencies; (vi) conversion efficiencies are lower for idle conditions, which can be a problem under traffic conditions where idle is a common situation; (vii) regardless of rpm and load, for the same flow rate the conversion efficiency is about the same; (viii) the model predictions slightly over estimate the exhaust gas temperature data at the catalyst outlet section with the observed differences decreasing with BMEP and engine speed; (ix) in general, the model predictions of the conversion efficiencies are satisfactory

2006-11-01

95

Method for generating a highly reactive plasma for exhaust gas after treatment and enhanced catalyst reactivity  

Energy Technology Data Exchange (ETDEWEB)

This patent application describes a method and apparatus of exhaust gas remediation that enhance the reactivity of the material catalysts found within catalytic converters of cars, trucks, and power stations.

Whealton, John H.; Hanson, Gregory R.; Storey, John M.; Raridon, Richard J.; Armfield, Jeffrey S.; Bigelow, Timothy S.; Graves, Ronald L.

2000-07-01

96

Numerical simulation of selective non-catalytic reduction of NO in exhaust gas with urea particle  

Energy Technology Data Exchange (ETDEWEB)

To reduce the amount of NO in exhaust gas from the furnace, a kinetics in the gas phase of Selective Non-Catalytic reduction of NO using urea and the characteristics of N{sub 2}O formation with NO reduction are investigated. Calculated results of NO and N{sub 2}O concentration are in accordance with experimental data from literature. Both calculated and measured NO concentrations show that NO concentration is minimum at 1250 K and N{sub 2}O concentration has the maximum peak at same temperature. Detailed study of the reaction mechanism of NO reduction is conducted and the important reactions in NO reduction and N{sub 2}O formation are explained. 14 refs., 9 figs., 1 tab.

Morozumi, Y.; Aoki, H.; Miura, T. [Tohoku University, Sendai (Japan). Dept. of Biochemistry and Engineering

1995-12-31

97

Exhaust gas feedback in an internal combustion engine. Abgasrueckfuehrung an einer Brennkraftmaschine  

Energy Technology Data Exchange (ETDEWEB)

A bypass line with a control valve is fitted between the suction and exhaust gas pipes of an internal combustion engine for mixing in the exhaust gas, which is connected via a linkage to the control lever of the fuel control device of the internal combustion engine, and which can be set to the open position in the range between tickover and part load and into the closed position between higher part load and full load by a control lever.

Sauter, J.

1984-06-07

98

High-Octane Fuel from Refinery Exhaust Gas: Upgrading Refinery Off-Gas to High-Octane Alkylate  

Energy Technology Data Exchange (ETDEWEB)

Broad Funding Opportunity Announcement Project: Exelus is developing a method to convert olefins from oil refinery exhaust gas into alkylate, a clean-burning, high-octane component of gasoline. Traditionally, olefins must be separated from exhaust before they can be converted into another source of useful fuel. Exelus’ process uses catalysts that convert the olefin to alkylate without first separating it from the exhaust. The ability to turn up to 50% of exhaust directly into gasoline blends could result in an additional 46 million gallons of gasoline in the U.S. each year.

None

2009-12-01

99

Development of dry analytical method for formaldehyde in exhaust emissions. Haishutsu gas chu no aldehyde no kanshiki bunsekiho no kaihatsu  

Energy Technology Data Exchange (ETDEWEB)

In the dry analytical method of formaldehyde in automobile exhaust emission, sampling conditions such as temperature and flow rate, and measurable concentration ranges were examined. Silicagel cartridges coated with 2,4-dinitrophenylhydrazin (DNPH) were prepared, and a prototype gas sampling system was fabricated to sample by both conventional impinger method and the cartridge method at the same time, and a high performance liquid chromatograph was used for analysis. As a result, since a collection efficiency reached 100% at 70 {degree} C in a high formaldehyde concentration range over 10ppm, it was necessary to heat a sampling line. As heated, formaldehyde was fully collected independently of moisture in exhaust emission, and a sampling rate of 0.5l/min was also desirable. The measurable concentration range entirely covered that of formaldehyde in exhaust emission, and a measurement accuracy was also equivalent to that of the impinger method. 4 refs., 7 figs., 4 tabs.

Akutsu, Y.; Sugano, H.; Hasegawa, T.; Ota, M. (Nissan Motor Co. Ltd., Tokyo (Japan) Yokohama Environmental Research Institute, Yokohama (Japan))

1990-04-25

100

Exhaust gas purification with sodium bicarbonate. Analysis and evaluation; Abgasreinigung mit Natriumhydrogencarbonat. Analyse und Bewertung  

Energy Technology Data Exchange (ETDEWEB)

The dry exhaust gas cleaning uses sodium bicarbonate in order to absorb acid components of exhaust gases such as sulphur dioxide or hydrochloric acid. Recently, sodium and calcium based adsorbents are compared with respect to their economic and ecologic options. None of the investigations performed considered decidedly practical experiences from the system operation such as differences in the management, availability, personnel expenditure and maintenance expenditure. Under this aspect, the authors of the contribution under consideration report on exhaust gas cleaning systems using sodium carbonate as well as lime adsorbents. The operators of these exhaust gas cleaning systems were questioned on their experiences, and all relevant operational data (consumption of additives, consumption of energy, emissions, standstill, maintenance effort) were recorded and evaluated at a very detailed level.

Quicker, Peter; Rotheut, Martin; Schulten, Marc [RWTH Aachen Univ. (Germany). Lehr- und Forschungsgebiet Technologie der Energierohstoffe (TEER); Athmann, Uwe [dezentec ingenieurgesellschaft mbH, Essen (Germany)

2013-03-01

 
 
 
 
101

Reduction of low temperature engine pollutants by understanding the exhaust species interactions in a diesel oxidation catalyst.  

Science.gov (United States)

The interactions between exhaust gas species and their effect (promotion or inhibition) on the light-off and activity of a diesel oxidation catalyst (DOC) for the removal of pollutants are studied, using actual engine exhaust gases from the combustion of diesel, alternative fuels (rapeseed methyl ester and gas-to-liquid fuel) and diesel/propane dual fuel combustion. The activity of the catalyst was recorded during a heating temperature ramp where carbon monoxide (CO) and hydrocarbon (HC) light-off curves were obtained. From the catalyst activity tests, it was found that the presence of species including CO, medium-heavy HC, alkenes, alkanes, and NOx and their concentration influence the catalyst ability to reduce CO and total HC emissions before release to the atmosphere. CO could inhibit itself and other species oxidation (e.g., light and medium-heavy hydrocarbons) while suffering from competitive adsorption with NO. Hydrocarbon species were also found to inhibit their own oxidation as well as CO through adsorption competition. On the other hand, NO2 was found to promote low temperature HC oxidation through its partial reduction, forming NO. The understanding of these exhaust species interactions within the DOC could aid the design of an efficient aftertreatment system for the removal of diesel exhaust pollutants. PMID:24450781

Lefort, I; Herreros, J M; Tsolakis, A

2014-02-18

102

Effect of operating and sampling conditions on the exhaust gas composition of small-scale power generators.  

Science.gov (United States)

Small stationary diesel engines, like in generator sets, have limited emission control measures and are therefore responsible for 44% of the particulate matter (PM) emissions in the United States. The diesel exhaust composition depends on operating conditions of the combustion engine. Furthermore, the measurements are influenced by the used sampling method. This study examines the effect of engine loading and exhaust gas dilution on the composition of small-scale power generators. These generators are used in different operating conditions than road-transport vehicles, resulting in different emission characteristics. Experimental data were obtained for gaseous volatile organic compounds (VOC) and PM mass concentration, elemental composition and nitrate content. The exhaust composition depends on load condition because of its effect on fuel consumption, engine wear and combustion temperature. Higher load conditions result in lower PM concentration and sharper edged particles with larger aerodynamic diameters. A positive correlation with load condition was found for K, Ca, Sr, Mn, Cu, Zn and Pb adsorbed on PM, elements that originate from lubricating oil or engine corrosion. The nitrate concentration decreases at higher load conditions, due to enhanced nitrate dissociation to gaseous NO at higher engine temperatures. Dilution on the other hand decreases PM and nitrate concentration and increases gaseous VOC and adsorbed metal content. In conclusion, these data show that operating and sampling conditions have a major effect on the exhaust gas composition of small-scale diesel generators. Therefore, care must be taken when designing new experiments or comparing literature results. PMID:22442670

Smits, Marianne; Vanpachtenbeke, Floris; Horemans, Benjamin; De Wael, Karolien; Hauchecorne, Birger; Van Langenhove, Herman; Demeestere, Kristof; Lenaerts, Silvia

2012-01-01

103

Suicide by carbon monoxide from car exhaust-gas in Denmark 1995-1999  

DEFF Research Database (Denmark)

In the period 1995-1999 there were 388 car exhaust-gas suicides in Denmark. Of these 343 (88.4%) were men and 45 (11.6%) were women, the average age being 47 years. The car exhaust-gas suicides made up 9.3% of all suicides in Denmark in the period. The corresponding rate was 11.7% for men and 3.7% for women. In rural areas a larger part of all suicides were committed with car exhaust-gas compared to the more densely populated areas. Mental disease was diagnosed in 124 (32.0%) cases. A suicide note was found in 165 (42.5%) cases. A hose was fitted to the exhaust pipe in 334 (86.1%) cases. Of these the 234 (60.3%) occurred outside, typically in a forest area, while 76 (19.6%) occurred in a closed garage. All the 54 (13.9%) cases with no hose fitted to the exhaust pipe occurred in a garage. Seven (1.8%) victims were found in a burning or burnt-out car, where the following investigation revealed that it was actually a car exhaust-gas suicide. Carboxyhemoglobin was measured in 26 (6.7%) victims. In two of these victims no carboxyhemoglobin was found, as they had survived for some time after the poisoning. The average saturation of the remaining victims was 67%, the lowest saturation being 20% and the highest being 84%. In the period 1969-1987 the number of car exhaust-gas suicides in Denmark increased from 50 to approximately 190 per year and the rate of car exhaust-gas suicides compared to all suicides increased from approximately 5% to approximately 13%. In 1987-1999 these figures decreased from approximately 190 to 63 per year and from 13% to approximately 8%. During these 30 years the number of passenger cars in Denmark doubled, which explains the increase in car exhaust-gas suicides during 1969-1987. A possible explanation for the decrease in 1987-1999 is the introduction of the catalytic converter, which was made mandatory in 1990. We anticipate that car exhaust-gas suicides will continue to decrease in numbers, as more cars are equipped with catalytic converters.

Thomsen, Asser H; Gregersen, Markil

2006-01-01

104

Heat-pipe assisted thermoelectric generators for exhaust gas applications  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Millions of hybrid cars are already running on our roads with the purpose of reducing fossil fuel dependence. One of their main advantages is the recovery of wasted energy, namely by brake recovery. However, there are other sources of wasted energy in a car powered by an internal combustion engine, such as the heat lost through the cooling system, lubrication system (oil coolers) and in the exhaust system. These energies can be recuperated by the use of thermoelectric generators (TEG) based o...

2010-01-01

105

Diesel engine exhaust gas recirculation--a review on advanced and novel concepts  

International Nuclear Information System (INIS)

Exhaust gas recirculation (EGR) is effective to reduce nitrogen oxides (NOx) from Diesel engines because it lowers the flame temperature and the oxygen concentration of the working fluid in the combustion chamber. However, as NOx reduces, particulate matter (PM) increases, resulting from the lowered oxygen concentration. When EGR further increases, the engine operation reaches zones with higher instabilities, increased carbonaceous emissions and even power losses. In this research, the paths and limits to reduce NOx emissions from Diesel engines are briefly reviewed, and the inevitable uses of EGR are highlighted. The impact of EGR on Diesel operations is analyzed and a variety of ways to implement EGR are outlined. Thereafter, new concepts regarding EGR stream treatment and EGR hydrogen reforming are proposed

2004-04-01

106

Platform for a Hydrocarbon Exhaust Gas Sensor Utilizing a Pumping Cell and a Conductometric Sensor  

Directory of Open Access Journals (Sweden)

Full Text Available Very often, high-temperature operated gas sensors are cross-sensitive to oxygen and/or they cannot be operated in oxygen-deficient (rich atmospheres. For instance, some metal oxides like Ga2O3 or doped SrTiO3 are excellent materials for conductometric hydrocarbon detection in the rough atmosphere of automotive exhausts, but have to be operated preferably at a constant oxygen concentration. We propose a modular sensor platform that combines a conductometric two-sensor-setup with an electrochemical pumping cell made of YSZ to establish a constant oxygen concentration in the ambient of the conductometric sensor film. In this paper, the platform is introduced, the two-sensor-setup is integrated into this new design, and sensing performance is characterized. Such a platform can be used for other sensor principles as well.

Ralf Moos

2009-09-01

107

Low-pressure-ratio regenerative exhaust-heated gas turbine. Final report  

Energy Technology Data Exchange (ETDEWEB)

A design study of coal-burning gas-turbine engines using the exhaust-heated cycle and state-of-the-art components has been completed. In addition, some initial experiments on a type of rotary ceramic-matrix regenerator that would be used to transfer heat from the products of coal combustion in the hot turbine exhaust to the cool compressed air have been conducted. Highly favorable results have been obtained on all aspects on which definite conclusions could be drawn.

Tampe, L.A.; Frenkel, R.G.; Kowalick, D.J.; Nahatis, H.M.; Silverstein, S.M.; Wilson, D.G.

1991-01-01

108

Catalytic study of SOFC electrode materials in engine exhaust gas atmosphere  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A single chamber solid oxide fuel cell (SC-SOFC) is a device able to produce electricity from a mixture of hydrocarbons and oxidant. An innovative application of this system would be to recover energy from exhaust gas of a thermal engine. This paper presents a study of stability and catalytic behaviour of electrode materials composing the cell in a mixture of hydrocarbons (propane, propene), oxygen, carbon monoxide, carbon dioxide, hydrogen and water corresponding to a composition of exhaust ...

Briault, Pauline; Rieu, Mathilde; Laucournet, Richard; Morel, Bertrand; Viricelle, Jean-paul

2013-01-01

109

APPLICATION GUIDE FOR THE SOURCE PM10 EXHAUST GAS RECYCLE SAMPLING SYSTEM  

Science.gov (United States)

The document describes assembly, operation, and maintenance of the Exhaust Gas Recycle (EGR) sampling system. The design of the sampling train allows the operator to maintain a constant flow rate through an inertial sampler while the gas flow rate into the sampling nozzle is adju...

110

Thermoelectric exhaust energy recovery with temperature control through heat pipes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Currently, a great deal of the automotive industry’s R&D effort is focused on improving overall vehicle environmental and energy efficiency. For instance, one of the things that Electric Vehicles (EVs) and Hybrid cars (HEV) have in common is the recovery of waste energy, namely during braking. But, when an I.C. engine is operating (e. g. as a range extender in an EV), a large amount of energy is also wasted within the exhaust gases and with engine cooling, energy that could otherwise be rec...

2011-01-01

111

Application of the water gas shift reaction to fusion fuel exhaust streams  

International Nuclear Information System (INIS)

In a Fusion Fuel Clean Up (FCU) system, impurities will be removed from the fusion reactor exhaust and neutral beam line streams. Tritium in this impurity stream will be recovered and recycled to the fuel stream. In one flowsheet configuration of the Tritium Systems Test Assembly (TSTA), tritium is recovered from a simulated impurity stream via uranium hot metal beds and recycled to an isotope separation system. This study has shown, however, that the catalyzed water gas shift reaction, by which (H,D,T)2O and CO are converted to (H,D,T)2 and CO2 is a better method of (H,D,T)2O reduction than the hot metal beds. Catalytic reactors were designed, built and tested to provide data for the design of a prototype reactor to replace the hot metal beds in the FCU system. The prototype reactor contains only 10 g of catalyst and is expected to last at least 5 years. The reactor is small (1.3 cm OD x 13 cm long), operates at low temperatures (approximately 490 K) and will convert water to hydrogen, at a CO/H2O ratio of 1.5, with an efficiency of greater than 98 percent. Results show that the catalytic reactor is very stable even during upset conditions. Wide ranges of flow and a CO/H2O ratio variance from 1.3 upward have little effect on the conversion efficiency. Short term high temperature excursions do not affect the catalyst and lower temperatures will simply decrease the reaction rate resulting in lower conversions. The reactor appears to be unaffected by NO2, CO2, O2 and N2 in the feed stream at concentration levels expected in a fusion reactor exhaust stream

1983-01-01

112

Heat revoery of boiler exhaust gas by improving feed water system. Kyusui keito no kaizen ni yoru boiler hai gas netsukaishu  

Energy Technology Data Exchange (ETDEWEB)

Heat recovery of boiler exhaust gas by improving feed water system of a paper mill was reported. Heat recovery was tried by boiler feed water because the exhaust gas temperature of recovery boiler was high, but a problem of heat recovery was involved due to high system temperature caused by recovered process drain and turbine condensate water. The feed water system was then reviewed. Because raising temperature by mixing process system drain and turbine condensate water is not a good policy, the drain of process system was separated from the drain recovered from turbine for subsequent filtering of drain. Drain of process system and ion exchange water were recovered through heat exchange and sent to ion exchange water tank to recover the drain into demineralized water tank. As a result of this, considerable steam of deaerator was saved. Exhaust gas temperature was also reduced from 200 {degree} to 140 {degree} and the energy saving efficiency of 4,095 tons per year as calculated in terms of coal was achieved. 3 tabs.

Okiyama, Y. (Jujo Paper Co. Ltd., Tokyo (Japan))

1991-02-04

113

Exhaust gas emissions from ethanol fuelled heavy duty vehicles  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the project was to contribute to the development of more efficient and better suited catalysts for ethanol fuelled diesel vehicles, by characterization of the emissions of both regulated and unregulated exhaust emission components at different driving conditions for a bus engine. Measurements on three commercial and one prototype catalyst were performed at 22 `steady state` loading points. The measurements included the regulated emission components carbon monoxide, hydrocarbons and nitrogen oxides and the non-regulated emission components ethanol, formaldehyde, acetaldehyde, acetic acid and some light hydrocarbons. The investigation shows that there are large differences between the commercial catalysts regarding the oxidation capacity and the selectivity. One of the catalysts showed a very high oxidation capacity but relatively low selectivity. The emissions of both nitrogen dioxide and acetic acid became with this catalyst considerably larger than for the other two. On the other hand did the emission of acetaldehyde become lower than for the other two. The catalyst which were developed especially for ethanol fuelled diesel vehicles showed somewhat higher selectivity for ethanol oxidation at most loading points. This gave very low emissions of acetic acid and low emissions of acetaldehyde. This catalyst showed on the other hand some oxidation of NO to NO{sub 2}. Ageing in diesel exhaust did not impair the performance of this catalyst 5 refs, 13 figs, 4 tabs

Pettersson, Esbjoern [Luleaa Univ. of Technology (Sweden). Dept. of Environment Technology

1997-12-01

114

Evaluation of Energy Saving Characteristics of a High-Efficient Cogeneration System Utilizing Gas Engine Exhaust Heat  

Science.gov (United States)

A high efficiency cogeneration system (CGS) utilizing high temperature exhaust gas from a gas engine is proposed. In the proposed CGS, saturated steam produced in the gas engine is superheated with a super heater utilizing regenerative burner and used to drive a steam turbine generator. The heat energy is supplied by extracting steam from the steam turbine and turbine outlet low-temperature steam. Both of the energy saving characteristics of the proposed CGS and a CGS constructed by using the original gas engine (GE-CGS) were investigated and compared, by taking a case where energy for office buildings was supplied by the conventional energy systems. It was shown that the proposed CGS has energy saving rate of 24.5%, higher than 1.83 times, compared with that of the original GE-CGS.

Pak, Pyong Sik

115

HEAT TRANSFER IN EXHAUST SYSTEM OF A COLD START ENGINE AT LOW ENVIRONMENTAL TEMPERATURE  

Directory of Open Access Journals (Sweden)

Full Text Available During the engine cold start, there is a significantly increased emission of harmful engine exhaust gases, particularly at very low environmental temperatures. Therefore, reducing of emission during that period is of great importance for the reduction of entire engine emission. This study was conducted to test the activating speed of the catalyst at low environmental temperatures. The research was conducted by use of mathematical model and developed computer programme for calculation of non-stationary heat transfer in engine exhaust system. During the research, some of constructional parameters of exhaust system were adopted and optimized at environmental temperature of 22 ?C. The combination of design parameters giving best results at low environmental temperatures was observed. The results showed that the temperature in the environment did not have any significant influence on pre-catalyst light-off time.

Snežana D Petkovi?

2010-01-01

116

Performance analysis for the characteristics of hybrid type absorption chiller operated by exhaust gas and hot water  

International Nuclear Information System (INIS)

The characteristics of hybrid type absorption chiller are studied numerically to use a waste hot water and exhaust hot gas effectively. As the partial load decreases, COP decreases but COPf increases. It is because of the system more rely upon the single effect cycle compare to the double effect cycle. So the consumption ratio of fuels increase and the save ratio decrease as the partial load decreases. For the same reason, as the inlet temperature and flow rate of hot water increase COP decreases but COPf increases. As the inlet temperature of the hot gas increase, COPf increases. It is because of the consumption ratio of fuels decreases as the inlet temperature of the hot gas increase.

2009-11-04

117

Energy efficient exhaust gas purification from waste incineration; Energieeffiziente Abgasreinigung bei der Abfallverbrennung  

Energy Technology Data Exchange (ETDEWEB)

Due to the increasing demands on the climate protection and the dwindling resources of primary energy, power generation from waste materials increasingly becomes important. The constantly increasing prices of primary energy give new incentives to use the energetic potentials in the exhaust gas. The energy efficiency of a thermal waste treatment plant depends on several factors. The boiler with the associated steam condenser system offers a great potential for the optimization. The author of the contribution under consideration reports on the potentials of energy optimization of exhaust gas purification procedures behind waste incineration plants. Basic possibilities of energy optimization are considered and presented in concrete existing plants as well as new plants.

Karpf, R. [ete.a Ingenieurgesellschaft mbH, Lich (Germany)

2011-07-01

118

Process for reducing harmful substances in exhaust gas/exhaust air by means of photosynthesising algae and device to carry out the process. Verfahren zur Minderung von Abgas-/Abluft-Schadstoffen mittels photosynthetisierender Algen und Vorrichtung zur Durchfuehrung des Verfahrens  

Energy Technology Data Exchange (ETDEWEB)

The process reported here uses the photosynthesis properties of micro-organisms which can stand extremes of harmful substances (micro-algae: cyanidium caldarium), using light energy to fix carbon dioxide, SO/sub 2/ and NO/sub x/ in biological compounds. Metal ions can be accumulated simultaneously. The process provides for the uncomplicated direct introduction of exhaust gas/exhaust air (temperature range: 40-80/sup 0/C) into the lighted culture. If sunlight is used, the process has a very favourable energy balance, as the harmful substances are converted biologically into compounds rich in energy, which can be reused (e.g. biogas).

Schimmelpfeng, L.; Thormaelen, C.

1986-09-25

119

Experimental study on engine gas-path component fault monitoring using exhaust gas electrostatic signal  

Science.gov (United States)

This paper presents the recent development in engine gas-path components health monitoring using electrostatic sensors in combination with signal-processing techniques. Two ground-based engine electrostatic monitoring experiments are reported and the exhaust gas electrostatic monitoring signal-based fault-detection method is proposed. It is found that the water washing, oil leakage and combustor linear cracking result in an increase in the activity level of the electrostatic monitoring signal, which can be detected by the electrostatic monitoring system. For on-line health monitoring of the gas-path components, a baseline model-based fault-detection method is proposed and the multivariate state estimation technique is used to establish the baseline model for the electrostatic monitoring signal. The method is applied to a data set from a turbo-shaft engine electrostatic monitoring experiment. The results of the case study show that the system with the developed method is capable of detecting the gas-path component fault in an on-line fashion.

Sun, Jianzhong; Zuo, Hongfu; Liu, Pengpeng; Wen, Zhenhua

2013-12-01

120

Reformulation of engine gasoline to reduce exhaust emissions in Finnish conditions. Effect of gasoline aromatics, olefins and T90 temperature on exhaust emissions  

International Nuclear Information System (INIS)

The research work focused on the effects of gasoline composition, i.e. aromatics and olefin contents and 90 % point of distillation, on exhaust emissions. The experimental part comprised exhaust gas measurements for 13 catalyst cars at +22 deg C and for one non-catalyst car at +22 deg C according to FTP75 driving cycle. Regulated emissions (THC, CO and NOx), non-regulated emissions (hydrocarbons and aldehydes), carbon dioxide and fuel consumption were measured. The high aromatics contents of eight test fuels were about 40 vol% and the low ones about 15 vol%, the high olefin contents were about 15 vol% and the low ones about 2 vol%, and the high T90 temperatures about +170 deg C and the low ones +145 deg C. The results were treated in two ways: effects of each single change in characteristics, and those of simultaneous changes in all fuel characteristics studied. The lowest CO and THC emissions for the catalyst cars at +22 deg C were obtained by reducing the aromatics content and the T90 temperature of the fuel, while the reduction of the olefin content increased respective emissions. The NOx emission increased when the aromatics content and T90 temperature were reduced, and decreased slightly when the olefin content was reduced. The CO2 emission and the fuel consumption (kg/100 km) were affected, i.e. reduced, only by a reduction in the aromatics content. However, the fuel consumption in volume units (1/100 kg) increased. The results at -7 deg C for THC and NOx emissions were along the same lines as at +22 deg C, except for the CO emission, which decreased when the olefin content was reduced and increased when the T90 temperature was lowered

1995-01-01

 
 
 
 
121

Responses of spruce seedlings (Picea abies) to exhaust gas under laboratory conditions. 2. ultrasonic changes and stomatal behaviour  

International Nuclear Information System (INIS)

This study examines the effects of exhaust gas exposure on the epistomatal wax structure and mesophyll ultrastructure in needles of Norway spruce (Picea abies (L.) Karst.) seedlings. Stomatal diffusive resistance was also measured. Two independent exhaust gas fumigations were performed: 100 and 200 ppb measured as NOx, for 10 days and 50, 100 and 200 ppb NOx for 19 days. The obstructive effect of exhaust gas exposure on epistomatal wax tubules was apparent. The stomata became covered by flat and solid wax resulting from the structural degradation of the wax crystalloids. Increasing the exhaust gas concentration in the chamber atmosphere exacerbated the degradation of the wax structure. Exhaust gas exposure induced aggregation and electron translucence of plastoglobuli, swelling of thylakoids, increase of cytoplasmic lipids and slight increase of vesiculation of cytoplasm in mesophyll cells of current and previous year needles. These changes were exemplified in current year needles. Damage to the epicuticular waxes and mesophyll ultrastructure of spruce needles most likely reflects the NOx and volatile hydrocarbon fraction. The alterations in epicuticular waxes and mesophyll ultrastructure can be related to accelerated senescence of the youngest, photosynthetically active, needle generation. The exhaust gas also resulted in decreased diffusive stomatal resistance at night which indicates that the exhaust gas exposure disturbed the gas exchange of spruce seedlings. The results show that even relatively short-term exposure to realistic concentrations of exhaust gas in the atmosphere can induce rather severe injuries to the needle surface structure as well as ultra-structure at the cellular level. (author)

2000-01-01

122

HPLC analysis of aldehydes in automobile exhaust gas: Comparison of exhaust odor and irritation in different types of gasoline and diesel engines  

International Nuclear Information System (INIS)

This study investigated high performance liquid chromatography (HPLC) to identify and measure aldehydes from automobile exhaust gas. Four aldehydes: formaldehyde (HCHO), acetaldehyde (CH3CHO), acrolein (H2C=CHCHO) and propionaldehyde (CH3CH2CHO) and one ketone, acetone (CH3)2CO are separated. The other higher aldehydes in exhaust gas are very small and cannot be separated. A new method of gas sampling, hereafter called bag sampling in HPLC is introduced instead of the trapping gas sampling method. The superiority of the bag sampling method is its transient gas checking capability. In the second part of this study, HPLC results are applied to compare exhaust odor and irritation of exhaust gases in different types of gasoline and diesel engines. Exhaust odor, irritation and aldehydes are found worst in direct injection (DI) diesel engines and best in some good multi-point injection (MPI) gasoline and direct injection gasoline (DIG) engines. Indirect injection (IDI) diesel engines showed odor, irritation and aldehydes in between the levels of MPI gasoline, DIG and DI diesel engines

2008-05-01

123

Exhaust Emissions from Seven LP Gas Powered Vehicles.  

Science.gov (United States)

An evaluation was undertaken of seven LP gas powered, standard sized American cars. The cars were equipped with V-8 engines, automatic transmissions and Algas Industries dual fuel carburetion systems. Each car was tested according to the proposed 1972 Fed...

H. A. Ashby

1970-01-01

124

Exhaust gas emission from ships in Norwegian coastal waters  

International Nuclear Information System (INIS)

For the following vessel categories bunker consumption and emission of greenhouse gases and SO2 has been calculated: Norwegian coastal trade, domestic ferries, fishing vessels (Norwegian), Norwegian military vessels, inter-coastal ferries, import and export, ships iron-ore from Narvik and Soviet vessels in transit. The carbon emission (CO2 as carbon) within 12 nautical miles has been calculated to 0.621 MtC (Mega ton carbon) and to 1.0 MtC within the economic zone for these vessel categories. The calculated ''inland waterways'' bunker consumption in this study deviates from the Central Bureau of Statistics of Norway and OECD/IEA figures by up to 25%. This large deviation supports the need for a uniform method to calculate ''inland waterways'' bunker consumption. Scenarios for the emission outlook for the years 1995, 2000 and 2005 are discussed and calculated. With 1988 as present level it is possible, according to these scenarios, to reduce the emission of NOx by close to 40% and SO2 by 85%. Reduction of greenhouse- and SO2 components in the exhaust gases from ships is today technically possible, but the demand for further research and development is significant. Compared with land-based low-emission technologies, the offshore technologies are years behind. 21 refs., 9 figs., 9 tabs

1991-01-01

125

Method of producing monolithic catalyst for purification of exhaust gas  

Energy Technology Data Exchange (ETDEWEB)

A method is described of producing a monolithic catalyst for simultaneous oxidation of carbon monoxide and hydrocarbons and reduction of nitrogen oxides in exhaust gases of internal combustion engines, the method including the steps of providing an active alumina base coating to a monlithic carrier by treating the monolithic carrier with a coating slip in which an active alumina powder containing cerium oxide, which is formed by thermal decomposition of a cerium salt applied to the active alumina as a solution, is dispersed and then baking the treated carrier, and depositing at least one noble metal selected from the group consisting of Pt, Rh and Pd on the coating by thermal decomposition of an aqueous solution of a compound of each selected noble metal on the coating, characterized in that a ceria powder is additionally dispersed in the coating slip; wherein the amount of the ceria powder is such that, in the coating, Ce of the ceria powder amounts to 5 to 50% by weight of the coating, and wherin the content of Ce in the active alumina powder is in the range from 1 to 5% by weight.

Sawamura, K.; Eto, Y.; Mine, J.; Masuda, K.

1986-05-06

126

Design analysis of an automotive exhaust gas sensor. [Control for air-fuel ratio  

Energy Technology Data Exchange (ETDEWEB)

This work demonstrates the brittle materials design methodology used in a new interdisciplinary program at the University of Washington. The component examined was a zirconia exhaust gas sensor. The evaluation included a finite element stress analysis, which was correlated with flexure stress data to determine a probability of failure of the component.

Gac, F.D.; Bieler, T.R.; Chakraverty, J.P.; Ewanich, J.T.; Georgiadis, C.; Inoue, O.; McLaren, D.; Taggart, R.

1980-07-01

127

Tritium treatment in the exhaust gas on LHD deuterium experiments  

International Nuclear Information System (INIS)

Present experiments in LHD are carried out using hydrogen or helium gas, and obtained the remarkable parameters. Now we are proposing next experimental campaign using deuterium gas. However, deuterium experiments are accompanied by the production of neutron and tritium. We must reduce the tritium release amount in the environment less than 3.7 GBq (0.1 Ci) in a year according to the local engagement. To ensure this regulation, two type of tritium removing systems are planed for installation. One is combination of a catalytic oxidation and a molecular sieve for vacuum pumping gas. The other is combination of a catalytic oxidation and a membrane dehumidifier, which has been developed in NIFS, for large amount of vacuum vessel purge gas treatment system. In addition to these, a high sensitivity tritium gas detector for online tritium monitor has been developed using a proton-conducting ceramic (or oxide) as a hydrogen isotope pump. The pumped tritium is condensed until the detectable concentration with a monitoring interval. This report describes two tritium removing systems and a high sensitive tritium monitor. (author)

2009-01-01

128

Technologies for increasing CO2 concentration in exhaust gas from natural gas-fired power production with post-combustion, amine-based CO2 capture  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Enhanced CO2 concentration in exhaust gas is regarded as a potentially effective method to reduce thehigh electrical efficiency penalty caused by CO2 chemical absorption in post-combustion capturesystems. The present work evaluates the effect of increasing CO2 concentration in the exhaust gas of gasturbine based power plant by four different methods: exhaust gas recirculation (EGR), humidification(EvGT), supplementary firing (SFC) and external firing (EFC). Efforts have been focused on the im...

Li, Hailong; Ditaranto, M.; Berstad, D.

2011-01-01

129

Application of a power recovery system to gas turbine exhaust gases  

International Nuclear Information System (INIS)

This paper discusses the application of a power recovery system to recover waste heat from the exhaust gases of gas turbines and convert this energy into shaft horsepower. Also discussed are power cycles, selection of power fluid, equipment selection, and application of the power recovery system to various gas turbines. Several charts and tables are included: process flow diagram, cycle efficiencies, curve for estimating recoverable horsepower

1979-03-15

130

Experimental analysis of a spark-ignition engine using exhaust gas recycle at WOT operation  

Energy Technology Data Exchange (ETDEWEB)

Spark-ignition engines are still a competitive solution in a great number of applications. European manufacturers are all involved in the effort of improving fuel economy, at least at some engine operating points while meeting, of course, the pollutant emission standards. The EGR technique, since a long time adopted in reducing the NO{sub x} formation rate, could be an effective system for fuel economy improvement. Mainly, a de-throttle effect and decreased heat losses to the walls can be obtained in this way. Furthermore, lower exhaust gas temperatures can be reached thus avoiding damages to the noble metals of catalytic converters. In this paper, the EGR technique has been widely investigated by carrying out an experimental analysis of a small, naturally aspirated, spark-ignition engine. In particular, at full or high load operation, attention has been paid to the combustion development and the influence of EGR rate on the values of spark advance, at knock onset limit, tolerated by the engine has been assessed. Due to lower temperature levels within the combustion chamber, the obtained results show a decreased octane requirement, thus an optimal choice of spark advance is possible. Hence a significant increase of engine efficiency has been obtained. (author)

Fontana, G.; Galloni, E. [Department of Industrial Engineering, University of Cassino, Via G. De Biasio 43, Cassino (Italy)

2010-07-15

131

Hydrogen combustion and exhaust emissions in a supercharged gas engine ignited with micro pilot diesel fuel  

Energy Technology Data Exchange (ETDEWEB)

A hydrogen combustion and exhaust emissions in a supercharged gas engine ignited with micro pilot diesel fuel was discussed in this presentation. A schematic diagram of the experimental study was first presented. The single cylinder, water-cooled, supercharged test engine was illustrated. Results were presented for the following: fuel energy and energy share (hydrogen and diesel fuel); pressure history and rate of heat release; engine performance and exhaust emissions; effect of nitrogen dilution on heat value per cycle; effect of N{sub 2} dilution on pressure history and rate of heat release; and engine performance and exhaust emissions. This presentation demonstrated that smooth and knock-free engine operation results from the use of hydrogen in a supercharged dual-fuel engine for leaner fuel-air equivalence ratios maintaining high thermal efficiency. It was possible to attain mor3 than 90 per cent hydrogen-energy substitution to the diesel fuel with zero smoke emissions. figs.

Tomita, E.; Kawahara, N. [Okayama Univ., Okayama (Japan); Roy, M.M. [Rajshahi Univ. of Engineering and Technology, Rajshahi (Bangladesh)

2009-07-01

132

Hydrogen combustion and exhaust emissions in a supercharged gas engine ignited with micro pilot diesel fuel  

International Nuclear Information System (INIS)

A hydrogen combustion and exhaust emissions in a supercharged gas engine ignited with micro pilot diesel fuel was discussed in this presentation. A schematic diagram of the experimental study was first presented. The single cylinder, water-cooled, supercharged test engine was illustrated. Results were presented for the following: fuel energy and energy share (hydrogen and diesel fuel); pressure history and rate of heat release; engine performance and exhaust emissions; effect of nitrogen dilution on heat value per cycle; effect of N2 dilution on pressure history and rate of heat release; and engine performance and exhaust emissions. This presentation demonstrated that smooth and knock-free engine operation results from the use of hydrogen in a supercharged dual-fuel engine for leaner fuel-air equivalence ratios maintaining high thermal efficiency. It was possible to attain mor3 than 90 per cent hydrogen-energy substitution to the diesel fuel with zero smoke emissions. figs.

2009-09-20

133

Measurement of gas-phase polycyclic aromatic hydrocarbons (PAH) in gasoline vehicle exhaust  

International Nuclear Information System (INIS)

Polycyclic aromatic hydrocarbons (PAH) are emitted at low levels from most combustion sources including motor vehicles. Extensive studies have been carried out in the past on the identification and quantitation of PAH in particular matter, primarily from diesel vehicles; however, only limited data are available on gas phase emissions from motor vehicles. Gas phase emissions are important from both a health perspective and because of their higher chemical reactivity during atmospheric transport. A method was sought to allow the authors to measure gas phase PAH in diluted vehicle exhaust over the relatively short collection times permitted during the U. S. Environmental Protection Agency (EPA) Urban Dynamometer Driving Schedule (UDDS) or Federal Test Procedure (FTP). In this paper, the authors describe their results on the development of a method using adsorption/thermal desorption with Tenax solid absorbent for the analysis of PAH and PAH derivatives in dilute vehicle exhaust

1992-08-23

134

Electron beam degradation of simulated toluene-containing exhaust gas  

International Nuclear Information System (INIS)

With toluene as an example, experimental investigation on VOCs treatment by electron beam irradiation was carried out. The system uses 0.8 MeV electron beams to irradiate simulated toluene-containing gases to 5kGy-40kGy for investigatiing effects of initial concentration, absorbed dose, humidity on toluene removal rate. The toluene removal rate increased with absorbed dose. With 0.5-l.2Nm3/h of the gas flow at an initial toluene concentration of 1600mg/Nm3, the toluene removal rate was 46.5% at 10kGy and 72.2% at 40kGy. And increasing humidity increased the toluene removal rate, too. Qualitative analysis on by-products of the toluene degradation was made by means of Gas Chromatogram-Mass Spectrometer (GC/MS) and Chromatography of Ions (IC). It was found that the by-products consist of mainly benzaldehyde and formic acid, plus a little benzoic acid, benzyl alcohol, methyl pyridine, nitrotoluene, o-cresol, phenol and benzoin ethyl etherl. Mechanisms of the E-beam toluene removal, i.e. the contributions of OH free radicals and O2 to the oxidation of toluene, were discussed. (authors)

2007-06-01

135

Analysis of Exhaust Gas Waste Heat Recovery and Pollution Processing for Z12V190 Diesel Engine  

Directory of Open Access Journals (Sweden)

Full Text Available With the increasingly prominent problem regarding rapid economy development and the gradually serious environmental pollution, the waste heat recovery and waste gas pollution processing have received significant attention. Z12V190 diesel engine has high fuel consumption and low thermal efficiency and releases large amounts of exhaust gas and waste heat into the atmosphere, causing serious problems of energy waste and environmental pollution. In this work, the diesel engine exhaust gas components are analysed and the diesel engine exhaust emission rates and exhaust gas waste heat rates are calculated. The calculating results proved the economic feasibility of waste heat recovery from Z12V190 diesel engine exhaust gas. Then, the mainly harmful components are analysed and the corresponding methods of purification and processing about Z12V190 diesel engine exhaust gas pollution discussed. In order to achieve full recovery of waste heat, save energy, purify treatment pollution and ultimate to lay the foundation for waste gas recovery and pollution treatment, the comprehensive process flows of Z12V190 diesel engine exhaust gas pollution processing and waste heat recovery are preliminary designed.

Hou Xuejun

2012-06-01

136

The effect of heat transfer on performance of the Diesel cycle and exergy of the exhaust gas stream in a LHR Diesel engine at the optimum injection timing  

International Nuclear Information System (INIS)

In this study, a Diesel cycle analysis taking combustion and heat transfer into account on performance has been performed. The effect of heat transfer is analysed in terms of design parameters such as compression ratio and cut-off ratio. The effects of heat transfer from the cylinder on exhaust temperature were also investigated for different heat transfer and combustion modes. It was observed that the work output and exhaust temperature proportionally increase with the decrease of heat transfer for a fixed combustion rate and cut-off ratio. In the experimental study, it was found that the minimum fuel consumption in the LHR engine compared to the standard (STD) engine was obtained with a 4 deg. crank angle (CA) retardation of the injection timing from the 38 deg. (CA). The decrease in specific fuel consumption at this injection timing reached 6%, and the increase in brake thermal efficiency was 2%. The exhaust temperature of the LHR Diesel engine with the injection timing of 38 deg. CA was 10.8% higher than that of the STD engine, whereas, the increase in the temperature reached 22.8% at 34 deg. CA. Thus, as a consequence of its great potential for optimisation of system performance, a comparative exergy analysis has been performed with the purpose of calculating the amount of available energy of the exhaust gas stream at the optimum injection timing (34 CA) for the LHR engine. While the maximum amount of available energy in the LHR engine exhaust gas stream with the injection timing of 38 deg. CA was 13.45%, the increase at the optimum injection timing of 34 deg. CA was found to reach 38%. It was concluded that the exhaust gas stream of a low heat rejection (LHR) Diesel engine is the most important source of available energy, which must be recovered via a secondary heat recovery system

2005-01-01

137

Micro- and Nanostructural Characteristics of Particles Before and After an Exhaust Gas Recirculation System Scrubber  

DEFF Research Database (Denmark)

This work provides insight into the morphology and mixing state of submicron particles in diesel exhaust from a ship engine with an exhaust gas recirculation scrubber. Particles from this low-speed ship engine on test bed were collected using a microinertial impactor with transmission electron microscopy (TEM) grids on two stages. Micro- and nanostructural characteristics of single particles were studied by TEM. Image analysis was carried out on overview and high-resolution images, revealing influence of the exhaust gas treatment (scrubber) on the particle morphology and mixing state. Soot agglomerates were found to be collapsed after scrubber, reflected by their change in fractal dimension (D-f ) from 1.88 to 2.13. Soot was predominantly found internally mixed with other components, with a higher degree of internal mixing observed after scrubber. Soot nanostructural characteristics on the near atomic scale such as layer distance, lamella length, and tortuosity were not observed to be influenced by the scrubber. We also found that particles in the size range between 30 and 50nm, which were abundant in the exhaust before and after scrubber, were not graphitic soot. Furthermore, we found indications that these particles are composed of other crystalline material (salts). Copyright 2013 American Association for Aerosol Research

Lieke, Kirsten Inga; Bilde, Merete

2013-01-01

138

Efficiency of thermoelectric recuperators of the exhaust gas energy of internal combustion engines  

Science.gov (United States)

Results of computer simulation of thermoelectric generators (TEG) using the exhaust heat of internal combustion engines are presented. Sectionalized generator schematics whereby maximum efficiency is achieved for cases of real temperature dependences of the most suitable thermoelectric materials are considered. A model optimized for minimum cost is considered as well. Results of experimental research on generator that employs exhaust heat from heat and electricity cogeneration plant with a diesel engine are presented. Computer simulation is verified by the test results. The outlook for application of such heat recuperators in stationary plants is considered.

Anatychuk, L. I.; Kuz, R. V.; Rozver, Yu. Yu.

2012-06-01

139

Experimental research on exhaust gas purifying facilities in incinerating treatment of radioactive wastes  

International Nuclear Information System (INIS)

Among the research on the incinerating treatment of combustible low level wastes, three items, that is, combustible low level radioactive wastes and incinerating treatment method, wet type exhaust gas purifying facilities and ceramic filter type dry exhaust gas purifying facilities, were selected, and experimental research was carried out on the main theme of exhaust gas purification in the incineration of low level radioactive wastes. The definition of combustible low level radioactive wastes was decided, and the wastes conforming to this criteria were investigated and classified. The combustible low level wastes generated in the Tokai Research Establishment were classified and weighed, and the results reflected well the state of activities. The change of radioactive wastes to radioactive aerosol, radioactive gas and residue by incineration was investigated. The effect of volume reduction by incineration was studied. The decontamination performance of wet purifying system, the release of tritium steam, the cooling capacity of scrubbers and their corrosion, the construction of the test incinerator using ceramic filters, and the various tests on ceramic filters are reported. (K.I.)

1988-01-01

140

Trigeneration scheme for energy efficiency enhancement in a natural gas processing plant through turbine exhaust gas waste heat utilization  

International Nuclear Information System (INIS)

Highlights: ? Efficiency enhancement of Natural Gas (NG) processing plants in hot/humid climates. ? Gas turbine waste heat powered trigeneration scheme using absorption refrigeration. ? Annual NG savings of 1879 MSCM and operating cost savings of US$ 20.9 million realized. ? Trigeneration scheme payback period estimated at approximately 1 year. ? Significant economical and environmental benefits for NG processing plants. - Abstract: The performance of Natural Gas Processing Plants (NGPPs) can be enhanced with the integration of Combined Cooling, Heating and Power (CCHP) generation schemes. This paper analyzes the integration of a trigeneration scheme within a NGPP, that utilizes waste heat from gas turbine exhaust gases to generate process steam in a Waste Heat Recovery Steam Generator (WHRSG). Part of the steam generated is used to power double-effect water–lithium bromide (H2O–LiBr) absorption chillers that provide gas turbine compressor inlet air-cooling. Another portion of the steam is utilized to meet part furnace heating load, and supplement plant electrical power in a combined regenerative Rankine cycle. A detailed techno-economic analysis of scheme performance is presented based on thermodynamic predictions obtained using Engineering Equation Solver (EES). The results indicate that the trigeneration system could recover 79.7 MW of gas turbine waste heat, 37.1 MW of which could be utilized by three steam-fired H2O–LiBr absorption chillers to provide 45 MW of cooling at 5 °C. This could save approximately 9 MW of electric energy required by a typical compression chiller, while providing the same amount of cooling. In addition, the combined cycle generates 22.6 MW of additional electrical energy for the plant, while process heating reduces furnace oil consumption by 0.23 MSCM per annum. Overall, the trigeneration scheme would result in annual natural gas fuel savings of approximately 1879 MSCM, and annual operating cost savings of approximately US$ 20.9 million, with a payback period of 1 year. This study highlights the significant economical and environmental benefits that could be achieved through implementation of the proposed integrated cogeneration scheme in NGPPs, particularly in elevated ambient temperature and humidity conditions such as encountered in Middle East facilities.

2012-05-01

 
 
 
 
141

Metal oxide coatings for piezoelectric exhaust gas sensors  

Energy Technology Data Exchange (ETDEWEB)

We have deposited ZrO{sub 2}, TiO{sub 2}, and SnO{sub 2} films on ST-cut quartz surface acoustic wave (SAW) devices via sol-gel techniques. The films range from 100 to 300 nm thick and have porosities after calcination at 300{degrees}C that range from 82-88 % for ZrO{sub 2}, 77-81% for TiO{sub 2}, and 57-66% for SnO{sub 2}. In all cases, we have varied the synthesis and processing parameters over a wide range to optimize film properties: metal ion concentration (0.05-1.0 M), the H{sub 2}O:metal ratio (0.3-5.3), the acid concentration in the sol (0.02-0.7 M), the modifier ligand:metal ratio (r = 0.0-1.0), the processing conditions (100-900{degrees}C). The modifier ligand, triethanolamine (TEA), is added to each solution to allow multilayer films to be made crack free. The multilayer films are studied by optical microscopy, ellipsometry, X-ray diffraction, and N{sub 2} sorption. Preliminary high temperature frequency response measurements to target gases, such as, H{sub 2}, NO, NO{sub 2}, and propylene indicate limited sensitivity for the configurations tested.

Anderson, M.T.; Cernosek, R.W.

1996-06-01

142

Chimney manual. Firing and exhaust gas systems: planning, calculation, construction; 3. ed.; Handbuch der Schornsteintechnik. Feuerungsanlagen und Abgassysteme: Planung, Berechnung, Ausfuehrung  

Energy Technology Data Exchange (ETDEWEB)

As more and more modern high-efficiency heat generators with low exhaust gas temperature are installed the early adjustment of heat generator and chimney or exhaust gas system is of increasing importance. This book goes into the following subjects of chimney technology: Development of chimney construction, fuels and combustion, bases of chimney technology, chimney systems (design and field of application), chimney and building, air-exhaust gas chimney systems for the connection to gas heating systems which are independent of room air, high-efficiency burner technology, construction and exhaust gas removal of open chimneys, isolated chimneys, chimney retrofitting, costs, environmental protection, building specifications, standards, regulations. (HW) [Deutsch] Durch den verstaerkten Einbau moderner Waermeerzeuger mit hohen feuerungstechnischen Wirkungsgraden und entsprechend niedrigen Abgastemperaturen kommt einer fruehzeitigen Abstimmung von Waermeerzeuger und Schornstein bzw. Abgasanlage steigende Bedeutung zu. Das vorliegende Buch stellt dabei folgende Themenbereiche der Schornsteintechnik vor: Entwicklung des Schornsteinbaus, Brennstoffe und Verbrennung, Grundlagen der Schornsteintechnik, Schornsteinsysteme (Ausfuehrung und Einsatzbereich), Schornstein und Gebaeude, Schornstein und Heizung, Luft-Abgas-Schornsteinsysteme (LAS) zum Anschluss von raumluftunabhaengigen Gasfeuerstaetten, Brennwerttechnik, Aufstellung und Abgasfuehrung von offenen Kaminfeuern, freistehende Schornsteine, Schornsteinsanierung, Kosten, Umweltschutz, Bauvorschriften, Normen, Richtlinien. (HW)

Hausladen, G.

1994-12-31

143

New exhaust gas turbo-super-chargers for the diesel engines of the future  

Energy Technology Data Exchange (ETDEWEB)

BBC has extended its existing range of turbo-superchargers by the units of type range 4. They are designed for charging pressure ratios between 3.5 and 4.5 and achieve overall efficiencies around 67%. Because of this new range, engine designers can now increase the specific output of their machines at a reasonable price by using these compact economic exhaust gas turbo-super-chargers.

Jung, D.

1980-01-01

144

PERFORMANCE AND EXHAUST GAS EMISSIONS ANALYSIS OF DIRECT INJECTION CNG-DIESEL DUAL FUEL ENGINE  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Existing diesel engines are under stringent emission regulation particularly of smoke and particulate matter in their exhaust. Compressed Natural Gas and Diesel dual fuel operation is regarded as one of the best ways to control emissions from diesel engines and simultaneously saving petroleum based diesel fuel. Dual fuel engineis a conventional diesel engine which burn either gaseous fuel or diesel or both at the same time. In the present paper an experimental research was carried out on a la...

2012-01-01

145

A comparison between the performance of different silencer designs for gas turbine exhaust systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The dissipative silencers used to attenuate noise emanating from air moving devices such as fans are normally of a simple splitter design, with parallel baffles of absorbent material arranged over the width of a duct. However in more specialist applications, such as the exhaust systems of gas turbines, different silencer geometries are often used. One such geometry is a so-called bar silencer, in which rectangular bars, or bricks, of absorbing material are placed in a lattice arrangement over...

Kirby, Ray; Williams, Paul; Hill, James

2012-01-01

146

Laboratory Scale of Liquid Coal Fuel Combustion Process and Exhaust Gas Formation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Problem statement: Much research of coal has been already undertaken to ascertain the possibilities of coal being used as substitute for heavy fuel oil in the transportation sector. The effects of using coal as transportation fuel to the environment must also be considered. This study will review several aspects of the coal oil combustion process including combustion behavior, flame stability, some emissions from exhaust gas; CO, NOx and the particulate matter in a well insu...

2010-01-01

147

5th international exhaust gas and particulate emissions forum. Proceedings; 5. Internationales Forum Abgas- und Partikelemissionen. Beitraege  

Energy Technology Data Exchange (ETDEWEB)

The Proceedings of the 5th International Exhaust Gas and Particulate Emissions Forum contains 22 printed contributions as well as a CD-ROM. The titles of them are: (1) Diesel Emissions Control in the United States - 2010 and Beyond; (2) The MBE90 commercial vehicle engine for EPA '07 emissions regulations; (3) Concepts for engines and exhaust-gas cleaning systems for heavy duty trucks of the future; (4) HD Engine Technology for Near-Zero Emissions and Lowest Cost of Ownership; (5) (Partially-) Homogeneous Diesel Combustion; (6) Exhaust gas sensors for NOx storage catalysts and ammonia-SCR systems; (7) Sensors for modern exhaust gas after-treatment systems; (8) New reducing agents for low NOx-SCR Techno-logy; (9) Exhaust gas Aftertreatment on Lean Burn Gasoline Direct Injection Engines: The System of TWC and NOx-Storage Catalyst; (10) New Platinum/Palladium based catalyzed filter technologies for future passenger car applications; (11) Development of a Roadway Hydrocarbon Sorption Model and Characterization of a Novel PM Generator; (12) Requirements for current and future particulate measurement instrumentation from the point of view of the Physikalisch-Technische Bundesanstalt; (13) Standardized dilution conditions for gravimetric PM sampling - measures to assure results that correlate; (14) Particle Counting according PMP; (15) Future high-confidence measurement of diesel particulate emissions for approval and development; (16) New developments in optical instrumentation for exhaust gas; (17) Simultaneous Detection of Gaseous and Particulate Exhaust Components by Photoacoustic Spectroscopy; (18) Boundaries of modern exhaust gas instrumentation; (19) Raising quality and reducing application effort through efficient data input to the particulate filter load model for a EURO5 diesel car; (20) Stop-start operation of diesel engines - modified require-ment for exhaust gas after-treatment?; (21) Particulates emission with Biodiesel B30 impact on CSF management; (22) Diesel engine soot and NOx emission modelling. (orig)

NONE

2008-12-11

148

The influence of H{sub 2} and CO on diesel engine combustion characteristics, exhaust gas emissions, and after treatment selective catalytic NO{sub x} reduction  

Energy Technology Data Exchange (ETDEWEB)

The requirement to significantly reduce NO{sub x} and particulate matter (PM) emissions while maintaining efficient combustion performance is one of the main drivers for internal combustion engine research. Modern diesel and premixed charge compression ignition (PCCI) engines have improved engine fuel economy and significantly reduced NO{sub x} and PM emissions achieved by advances in both combustion and exhaust aftertreatment technologies. To date, it has been shown that vehicle emissions can be further improved by several catalytic systems including fuel reformers (i.e. partial oxidation, autothermal, and exhaust gas reforming) and aftertreatment systems, such as the selective catalytic reduction (SCR) of NO{sub x} under oxygen-rich conditions. Among the most promising on-board reforming technologies is the exhaust-gas reforming, which allows the fuel/air feed to the engine to be enriched with reformate containing H{sub 2} and CO. This method is a combination of reforming and exhaust-gas recirculation (EGR) and referred to as REGR. This paper reports on experimental results obtained when 1%Pt/Al{sub 2}O{sub 3} low temperature hydrocarbon-SCR catalyst was used to treat exhaust gas from a diesel engine operating with addition of simulated REGR (two different compositions). It has been shown that while REGR can directly improve engine performance and emissions by promoting the PCCI combustion mode, it can also benefit the performance of the SCR catalysts due to the presence of unburnt H{sub 2} in the exhaust gas. (author)

Abu-Jrai, A.; Tsolakis, A. [University of Birmingham, Birmingham (United Kingdom). School of Engineering, Mechanical and Manufacturing Engineering; Megaritis, A. [Brunel University, Uxbridge (United Kingdom). Mechanical Engineering, School of Engineering and Design

2007-10-15

149

Study on using acetylene in dual fuel mode with exhaust gas recirculation  

International Nuclear Information System (INIS)

Interest in employing gaseous fuels to internal combustion (IC) engines whether for stationary or mobile automotive applications has gained importance because of the economical, sustainable and environmental technical features associated with their usage. However, the incidence of preignition and knock remains a significant barrier in achieving their optimum performance potential. With the advent of latest technologies, the above barriers are eliminated. One such technique is timed manifold injection (TMI) of the gaseous fuel, which is controlled electronically to precisely monitor the induction of fuel to overcome the preignition problem in the intake. In the present investigation, acetylene was injected in the intake manifold in a single cylinder diesel engine, with a gas flow rate of 240 g/h, start of injection time is 10o aTDC and 90o CA (9.9 ms) duration, operated in dual fuel mode. In order to decrease the NOx emissions from acetylene-diesel engine, cooled EGR was employed. The cylinder pressure, brake thermal efficiency and emissions such as NOx, smoke, CO, HC, CO2 and exhaust gas temperature were studied. Dual fuel operation with acetylene induction coupled with cooled EGR results in lowered NOx emissions and improved part load performance. -- Highlights: ? Acetylene was tried in SI engines, but due to backfire further research was hindered as an alternative fuel. ? But it is not tried in CI engine. Timed manifold injection was tried in diesel engine in the present work to combat backfire. ? Author was successful in running the diesel engine in dual fuel mode. ? 21% maximum diesel replacement was achieved. Author is confident that acetylene will be commercialised as a fuel for diesel engine in future.

2011-05-01

150

Gas-phase polynuclear aromatic hydrocarbons (PAH) in vehicle exhaust: A method for collection and analysis  

International Nuclear Information System (INIS)

Gas-phase polynuclear aromatic hydrocarbons (PAH) are emitted at low levels in vehicle exhaust compared to other hydrocarbon emissions. A method has been developed involving the trapping of gas phase emissions on Tenax, a macrorecticular porous polymer, followed by thermal desorption onto a capillary gas chromatography column. Gas chromatography/mass spectrometry (GC/MS) was used for the chemical analysis. A detection limit of 0.05 ng was achieved for several gas-phase PAH. This high sensitivity enables the speciation and quantitation of gas-phase PAH collected from a dilution tube during standard driving (test) cycles. The method was demonstrated for the analysis of 9 PAH in the exhaust from a 1987 vehicle (with and without catalyst) during the hot start transient phase of the EPA urban dynamometer driving schedule. The PAH measured include naphthalene, 2-methyl- and 1-methylnaphthalene, biphenyl, fluorene, phenanthrene, anthracene, fluoranthene and pyrene. The four most abundant PAH observed are naphthalene, 2-methyl and 1-methylnaphthalene, and biphenyl, in that order

1990-06-06

151

Enhanced Performance of Discharge Plasma in Raw Engine Exhaust Treatment-Operation under Different Temperatures and Loads  

Science.gov (United States)

This paper reports improved performance of discharge plasma in raw engine exhaust treatment. For the purpose of investigation, both filtered and raw diesel engine exhaust were separately treated by the discharge plasma. In raw exhaust environment, the discharge plasma exhibits a superior performance with regard to NOx removal, energy consumption and formation of by-products. In this study, experiments were conducted at conditions of different temperatures and loads.

B, S. Rajanikanth; A, D. Srinivasan; Subhankar, das

2005-08-01

152

Passenger car exhaust emissions  

Energy Technology Data Exchange (ETDEWEB)

This monograph sets out to identify, objectively, the significance of the exhaust gas constituents of spark-ignition passenger car engines and present the information in a unbiased and non-political manner. It has also endeavoured to promulgate the factors that influence the generation and promotion of the individual components in an effort to identify the means of controlling the unwanted ones. The monograph has established that the nature of the exhaust gas products is essentially dependent on combustion time, combustion temperature and chemical species, and that combustion abnormalities, such as engine mis-fire, normally increase pollutant levels. The constituents causing most concern, amounting to less than 1% of the total volume of exhaust gas, are unburnt hydrocarbons (HCs), carbon monoxide (CO) and oxides of nitrogen (NOx). However, the carbon dioxide (CO[sub 2]) emission of 18% is now also causing concern with its association with the global warming effect (greenhouse effect). (author)

Goldsmith, R.

1990-01-01

153

Mining utilization of residues of exhaust gas cleaning from waste incinerators; Bergtechnische Verwertung von Abgasreinigungsrueckstaenden aus Verbrennungsanlagen  

Energy Technology Data Exchange (ETDEWEB)

The exhaust gas purification of a household incinerator or a substitute fuel power plant intends to remove dust, heavy metal compounds and acid harmful gases from the exhaust gas in order to comply with the immission-control legal limits. The particulate matter contains volatile heavy metal chlorides which precipitate as a solid matter. The enhanced amount of water-soluble salts is conspicuous. The concentration of soluble components is limited to 10,000 mg/L in the 1:10 eluate due to the landfill regulation. Thus, the residues of exhaust gas cleaning are predestined for an underground waste disposal in salt mines. Under this aspect, the author of the contribution under consideration reports on the mining utilization of residues of exhaust gas cleaning from waste incinerators.

Werthmann, Rainer [K+S Entsorgung GmbH, Kassel (Germany). Abfallchemie und Zulassungen

2013-03-01

154

Electric city traffic. A contribution to the solution of the noise pollution and exhaust gas problems  

Energy Technology Data Exchange (ETDEWEB)

With contributions coming from the fields of city planning, transportation, noise pollution abatement, systems analysis and data processing a research program investigated into the possible improvement of city environments (noise pollution and air pollution) by the use of electric-powered vehicles. A brief survey is given of the transportation and environment aspects of traffic noise, exhaust gases, recent automotive engineering developments, the development of traffic and the state of the art of electric traffic. Tables facilitate access to feasible ways of implementing a larger number of electric-powered vehicles. The paper includes cost-benefit analyses and references to further studies (determination of structural data of transportation, noise and exhaust gas tests for alternative-fuel vehicles). The spreading of electric-powered vehicles will be a matter of external influences, i.e. the development of petroleum prices, the political will of reducing the petroleum dependence and the political will of reducing urban environmental loads. (HWJ).

Schmitz, H.P.

1987-01-01

155

An experimental investigation on hydrogen as a dual fuel for diesel engine system with exhaust gas recirculation technique  

Energy Technology Data Exchange (ETDEWEB)

With higher rate of depletion of the non-renewable fuels, the quest for an appropriate alternative fuel has gathered great momentum. Though diesel engines are the most trusted power sources in the transportation industry, due to stringent emission norms and rapid depletion of petroleum resources there has been a continuous effort to use alternative fuels. Hydrogen is one of the best alternatives for conventional fuels. Hydrogen has its own benefits and limitations in its use as a conventional fuel in automotive engine system. In the present investigation, hydrogen-enriched air is used as intake charge in a diesel engine adopting exhaust gas recirculation (EGR) technique with hydrogen flow rate at 20 l/min. Experiments are conducted in a single-cylinder, four-stroke, water-cooled, direct-injection diesel engine coupled to an electrical generator. Performance parameters such as specific energy consumption, brake thermal efficiency are determined and emissions such as oxides of nitrogen, hydrocarbon, carbon monoxide, particulate matter, smoke and exhaust gas temperature are measured. Usage of hydrogen in dual fuel mode with EGR technique results in lowered smoke level, particulate and NO{sub x} emissions. (author)

Saravanan, N.; Nagarajan, G.; Kalaiselvan, K.M.; Dhanasekaran, C. [Internal Combustion Engineering Division, Department of Mechanical Engineering, College of Engineering, Guindy, Anna University, Chennai 600025 (India)

2008-03-15

156

Emission factor of exhaust gas constituents during the pyrolysis of zinc chloride immersed biosolid.  

Science.gov (United States)

Pyrolysis enables ZnCl2 immersed biosolid to be reused, but some hazardous air pollutants are emitted during this process. Physical characteristics of biosolid adsorbents were investigated in this work. In addition, the constituents of pyrolytic exhaust were determined to evaluate the exhaust characteristics. Results indicated that the pyrolytic temperature was higher than 500 °C, the specific surface area was >900 m(2)/g, and the total pore volume was as much as 0.8 cm(3)/g at 600 °C. For non-ZnCl2 immersed biosolid pyrolytic exhaust, VOC emission factors increased from 0.677 to 3.170 mg-VOCs/g-biosolid with the pyrolytic temperature increase from 400 to 700 °C, and chlorinated VOCs and oxygenated VOCs were the dominant fraction of VOC groups. VOC emission factors increased about three to seven times, ranging from 1.813 to 21.448 mg/g for pyrolytic temperatures at 400-700 °C, corresponding to the mass ratio of ZnCl2 and biosolid ranging from 0.25-2.5. PMID:23471775

Chiang, Hung-Lung; Lin, Kuo-Hsiung; Chiu, Hua-Hsien

2013-08-01

157

Responses of spruce seedlings (Picea abies) to exhaust gas under laboratory conditions--I. Plant-insect interactions.  

Science.gov (United States)

The effects of motor vehicle exhaust gas on Norway spruce seedlings (Picea abies (L.) Karst) and plant-insect interaction of spruce shoot aphid (Cinara pilicornis Hartig) was studied. The exhaust gas concentrations in the fumigation chambers were monitored and controlled by measuring the concentration of nitrogen oxides (NO(x)) with a computer aided feedback system. The concentrations of major exhaust gas components (black carbon [BC], fine particles, VOCs and carbonyl compounds) in the chamber air were also measured. Responses of Norway spruce seedlings to a 2 and 3-week exhaust gas exposure and subsequent performance of spruce shoot aphid were studied using realistic exposure regimes; 50, 100 and 200 ppb NO(x). The feedback control system based on NO(x) concentrations proved an adequate and practical means for controlling the concentration of exhaust gases and studying plant responses in controlled environment chambers. The exhaust exposure resulted in increased concentrations of proline, glutamine, threonine, aspartic acid, glycine and phenylalanine and decreased concentration of arginine, serine, alanine and glycine in young needles. No changes in soluble N concentrations were observed. The results are interpreted as a stress response rather than use of NO(x) as a nitrogen source. No changes in total phenolics and only transient changes in some individual terpene concentrations were detected. The exhaust gas exposure stressed the exposed seedlings, but had no significant effect on N metabolism or the production of defence chemicals. Aphid performance was not significantly affected. Soluble N, secondary metabolism and aphid performance were not sensitive to exhaust gas exposure during shoot elongation in Norway spruce. PMID:15093012

Viskari, E L; Surakka, J; Pasanen, P; Mirme, A; Kössi, S; Ruuskanen, J; Holopainen, J K

2000-01-01

158

Temperature, Pressure, and Infrared Image Survey of an Axisymmetric Heated Exhaust Plume  

Science.gov (United States)

The focus of this research is to numerically predict an infrared image of a jet engine exhaust plume, given field variables such as temperature, pressure, and exhaust plume constituents as a function of spatial position within the plume, and to compare this predicted image directly with measured data. This work is motivated by the need to validate computational fluid dynamic (CFD) codes through infrared imaging. The technique of reducing the three-dimensional field variable domain to a two-dimensional infrared image invokes the use of an inverse Monte Carlo ray trace algorithm and an infrared band model for exhaust gases. This report describes an experiment in which the above-mentioned field variables were carefully measured. Results from this experiment, namely tables of measured temperature and pressure data, as well as measured infrared images, are given. The inverse Monte Carlo ray trace technique is described. Finally, experimentally obtained infrared images are directly compared to infrared images predicted from the measured field variables.

Nelson, Edward L.; Mahan, J. Robert; Birckelbaw, Larry D.; Turk, Jeffrey A.; Wardwell, Douglas A.; Hange, Craig E.

1996-01-01

159

Ion beam analyses of particulate matter in exhaust gas of a ship diesel engine  

International Nuclear Information System (INIS)

There is an urgent need to reduce emission of the particulate matter (PM) in the exhaust gas from ship diesel engines causing various health hazards and serious environmental pollution. Usually the heavy fuel oil (HFO) for ships is of low quality, and contains various kinds of impurities. Therefore, the emission of PM along with exhaust gas from ship diesel engines is one of the most serious environmental issues. However, the PM fundamental properties are not well known. Therefore, it is important to perform elemental analysis of the PM. The HFO contains sulfur with a relatively high concentration of a few percent. It is important to make quantitative measurements of sulfur in the PM, because this element is poisonous for the human body. In the present work, PM samples were collected from exhaust gas of a test engine, and RBS and PIXE analyses were applied successfully to quantitative analysis of the PM samples. The RBS analysis enabled quantitative analysis of sulfur and carbon in the collected PM, while heavier elements such as vanadium and iron were analyzed quantitatively with the PIXE analysis. It has been found that the concentration ratio of sulfur to carbon was between 0.007 and 0.012, and did not strongly depend on the output power of the engine. The S/C ratio is approximately equal to the original composition of the HFO used in the present work, 0.01. From the known conversion ratio 0.015 of sulfur in the HFO to sulfates, the conversion ratio of carbon in the HFO to the PM is found to be 0.01–0.02 by the RBS measurements. On the other hand, the PIXE analysis revealed a vanadium enrichment of one order of magnitude in the PM.

2011-12-15

160

Variable-geometry turbocharger with asymmetric divided volute for engine exhaust gas pulse optimization  

Science.gov (United States)

A turbine assembly for a variable-geometry turbocharger includes a turbine housing defining a divided volute having first and second scrolls, wherein the first scroll has a substantially smaller volume than the second scroll. The first scroll feeds exhaust gas to a first portion of a turbine wheel upstream of the throat of the wheel, while the second scroll feeds gas to a second portion of the wheel at least part of which is downstream of the throat. Flow from the second scroll is regulated by a sliding piston. The first scroll can be optimized for low-flow conditions such that the turbocharger can operate effectively like a small fixed-geometry turbocharger when the piston is closed. The turbine housing defines an inlet that is divided by a dividing wall into two portions respectively feeding gas to the two scrolls, a leading edge of the dividing wall being downstream of the inlet mouth.

Serres, Nicolas (Epinal, FR)

2010-11-09

 
 
 
 
161

Multiple Exhaust Nozzle Effects on J-2X Gas Generator Outlet Impedance  

Science.gov (United States)

The current test setup of the J-2X gas generator system uses a multiple nozzle configuration to exhaust hot gases to drive the propellant supply turbines. Combustion stability assessment of this gas generator design requires knowledge of the impedance effects the multiple nozzle configuration creates on the combustion chamber acoustic modes. Parallel work between NASA and Sierra Engineering is presented, showing two methods used to calculate the effective end impedance resulting from multiple nozzle configurations. The NASA method is a simple estimate of the effective impedance using the long wavelength approximation. Sierra Engineering has developed a more robust numerical integration method implemented in ROCCID to accommodate for multiple nozzles. Analysis using both methods are compared to J-2X gas generator test data collected over the past year.

Kenny, R. Jeremy; Muss, Jeffrey; Hulka, James R.; Casiano, Matthew

2010-01-01

162

Evaluation of an exhaust gas evacuation system during propane-fueled lift truck maintenance  

International Nuclear Information System (INIS)

Exposure to carbon monoxide (CO) gas in the workplace can cause health problem. CO gas is colourless and odourless, and exposure to it can cause intoxication, particularly for mechanics working on internal combustion engines fed by propane-fueled lift trucks. Regular procedures for evacuating the gases emitted during routine mechanical repairs involve the use of rigid evacuating pipes attached to the building and hooked to a flexible pipe at the end of the exhaust pipe. With lift trucks, this procedure is limited because of the configuration of these vehicles, and also because this type of work is often done in places without access to permanent mechanical ventilation. The object of this study was to propose a new evacuation method for CO gas fumes that would lower the exposures of fumes for mechanics and for workstations. It identified the criteria that should be considered, such as the configuration of the existing exhaust system of lift trucks, and feasibility of using this system at a variety of on-site locations. The design of the device was described and evaluated. 7 refs., 6 tabs., 8 figs., 3 appendices

2006-08-01

163

Remote gas analysis of aircraft exhausts using FTIR-emission-spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

FITR emission spectroscopy as a remote sensing multi-component analyzing technique was investigated to determine the composition of aircraft exhausts at ground level. A multi-layer radiative transfer interpretation software based on a line-by-line computer algorithm using the HITRAN data base was developed. Measurements were carried out with different engine types to determine the traceable gas species and their detection limits. Finally validation measurements were made to compare the results of the system to those of conventional equipment. (author) 8 refs.

Heland, J.; Schaefer, K. [Fraunhofer Inst. for Atmospheric Environmental Research, Garmisch-Partenkirchen (Germany)

1997-12-31

164

Computers for exhaust gas analysis supply exact data; Abgasanalysecomputer liefern genaue Daten  

Energy Technology Data Exchange (ETDEWEB)

There is enormous potential for the reduction of off-gas emissions in domestic space and water heating by technical optimisation. Modern computers for exhaust analysis provide accurate combustion data. (orig.) [German] Da Heizung und Warmwasserbereitung den - mit Abstand -groessten Energieverbrauch in Wohnhaeusern verursachen liegt hier ein enormes Potential zur Senkung der Abgasmengen. Soll also der vornehmlich darauf zurueckzufuehrende Treibhauseffekt reduziert werden gilt es, Feuerstaetten technisch so zu optimieren, dass nur noch ein Minimum an Schadstoffen freigesetzt wird. Zur exakten Beurteilung der Verbrennungswerte sind moderne Abgasanalysecomputer heute das Mass der Dinge. (orig.)

Last, D. [Buero fuer Presse- und Oeffentlichkeitsarbeit H.D. Wollenberg, Montabaur (Germany)

2004-06-01

165

Apparatus for regulating the exhaust gas recirculation rate in internal combustion engines having self-ignition  

Energy Technology Data Exchange (ETDEWEB)

An apparatus for regulating the exhaust gas recycling rate in an internal combustion engine having self-ignition is proposed, in which a set-point or nominal ignition delay value is ascertained, and the actual ignition delay value is regulated to this nominal value. The nominal ignition delay value is efficaciously derived from a multi-dimensional memory, the coordinate values of which are dependent on at least load and rpm. The ignition delay time is ascertained from a comparison of the signal for the injection onset of an injection nozzle, for instance, and the signal of a pressure sensor communicating with the combustion chamber.

Ripper, W.

1984-02-28

166

Catalysts as Sensors—A Promising Novel Approach in Automotive Exhaust Gas Aftertreatment  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Sensors that detect directly and in situ the status of automotive exhaust gas catalysts by monitoring the electrical properties of the catalyst coating itself are overviewed. Examples included in this review are the in-situ determination of the electrical impedance of three-way catalysts based on ceria-zirconia solutions and of lean NOx traps of earth-alkaline based coatings, as well as approaches to determine the ammonia loading in Fe-SCR-zeolites with electrical ac measurements. Even more s...

Moos, Ralf

2010-01-01

167

Numerical Simulation of Exhaust Gas Cooling in Channels with Periodic Elbows for Application in Compact Heat Recovery Systems  

Science.gov (United States)

Miniature and Micro devices represent the new frontier for advanced heat and mass transfer technology. Due to the small length scales, the use of CFD is very useful for designing and optimizing microfluidic devices since experimentation and visualization at these scales can be difficult. In this work a high temperature air microfluidic cooling strategy for applications such as compact waste heat recovery, exhaust gas recirculation and fuel cell thermal management is proposed. Initially, the application of a simple straight microchannel is considered. In an effort to partially compensate for the poor thermal properties of air, right-angle bends are introduced in order to induce Dean vortices which periodically restart the thermal boundary layer development, thus improving the heat transfer and fluid mixing. Numerical simulations in the range of 100 heat transfer in the channels while increasing the pressure drop. Design considerations are discussed which take into account the heat transfer and pressure drop characteristics of the channels.

Di Bari, Sergio; Cotton, James S.; Robinson, Anthony J.

2012-11-01

168

Use of a remote plasma source for CVD chamber clean and exhaust gas abatement applications  

Energy Technology Data Exchange (ETDEWEB)

Remote plasma sources have traditionally been used in semiconductor processing applications such as dry removal of photoresist, where the capability of delivering a large flux of atomic oxygen into a semiconductor process chamber, with little of the associated plasma used to dissociate the oxygen, has made them attractive. With the development of fluorine-compatible remote plasma sources, a range of new application opportunities has opened up. In remote cleaning of CVD chambers, the remote plasma source is positioned before the process chamber, and a stream of atomic fluorine from the source is flowed into the chamber, where it can effectively clean a wide variety of materials such as SiO{sub 2}, Si{sub 3}N{sub 4}, and W. The cleaning process is purely chemical, with no associated in-situ plasma which can cause degradation of the process chamber. In exhaust gas abatement, the remote plasma source is located between the outlet of the etch or deposition process chamber and the mechanical pump. By adding appropriate gases, the exhaust stream from the chamber can be converted to form which can be managed more readily. Using a robust toroidal plasma source design, the ASTRON{trademark} remote plasma source has been used to address both of these areas. As an atomic fluorine source, over the typical operating range of 2--10 Torr several SLM of gases such as NF{sub 3} can be fully dissociated. As an exhaust gas abatement device, with operating pressure in the 0.1--1.0 Torr regime, abatement of perfluorocompounds (PFC's) at greater than 95% levels has been demonstrated. Using a variety of techniques--FTIR, RGA, and sample etching--the operation of this source technology and issues such as transport of atomic fluorine over substantial distances has been investigated.

Holber, W.; Chen, X.; Smith, D.; Besen, M.

1999-07-01

169

Effect of Operating and Sampling Conditions on the Exhaust Gas Composition of Small-Scale Power Generators  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Small stationary diesel engines, like in generator sets, have limited emission control measures and are therefore responsible for 44% of the particulate matter (PM) emissions in the United States. The diesel exhaust composition depends on operating conditions of the combustion engine. Furthermore, the measurements are influenced by the used sampling method. This study examines the effect of engine loading and exhaust gas dilution on the composition of small-scale power generators. These gener...

2012-01-01

170

Effect of operating and sampling conditions on the exhaust gas composition of small-scale power generators  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Small stationary diesel engines, like in generator sets, have limited emission control measures and are therefore responsible for 44% of the particulate matter (PM) emissions in the United States. The diesel exhaust composition depends on operating conditions of the combustion engine. Furthermore, the measurements are influenced by the used sampling method. This study examines the effect of engine loading and exhaust gas dilution on the composition of small-scale power generators. These gener...

2012-01-01

171

Implementation of an experimental pilot reproducing the fouling of the exhaust gas recirculation system in diesel engines  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The European emission standards EURO 5 and EURO 6 define more stringent acceptable limits for exhaust emissions of new vehicles. The Exhaust Gas Recirculation (EGR) system is a partial but essential solution for lowering the emission of nitrogen oxides and soot particulates. Yet, due to a more intensive use than in the past, the fouling of the EGR system is increased. Ensuring the reliability of the EGR system becomes a main challenge. In partnership with PSA Peugeot Citroën, we designed an ...

Gaborieau Cécile; Sommier Alain; Toutain Jean; Anguy Yannick; Crepeau Gérald; Gobin Benoît

2012-01-01

172

Oxidation and exhaust gas corrosion resistance of the cobalt base clad layers  

Directory of Open Access Journals (Sweden)

Full Text Available Purpose: Purpose of this work is describing the behaviour of the cobalt base cladding layers after treatment in hot air (750°C, 200 hours and exhaust gases (700°C, two month.Design/methodology/approach: The layers were produced by two cladding, laser and PTA, cladding technique. Cladding was conducted with a high power diode laser HDPL ROFIN SINAR DL 020 and Plasma Transformed Arc method. The layers consisted of three multitracking sublayers. The cobalt base layers were evaluated by microstructure investigations (optical and scanning electron microscope SEM, chemical analysis and micro hardness measurements.Findings: The microstructure of the investigated layers did not change much, neither on the top part nor in the clad/steel interface after treatment in both environments. On the outer surfaces the oxide layers were observed which consisted generally of chromium and iron oxides. The compositions of this scales were reviled by the EDS analyze. The changes in chemical compositions before and after oxidation and after corrosion in exhaust gases in the dendritic regions and micro regions were confirmed by the semi-quantitative chemical analysis (EDS. Neither the oxidation nor exposition for two month in exhaust gases did not influence on the morphology of the clad layers in any region however changes in chemical composition were observed. For both sort of clads the oxide layers were observed on the surface. The proposed layers are resistant for the hot exhausted gases.Research limitations/implications: The future researches should be done on microstructural and kinetic analyze of high temperature corrosion for higher temperature and times of the process.Practical implications: The clad layers, of this composition, were designed as a method to prolong service time for the ship engine exhausted valve and after this investigation the first valve heads with laser clad layer were installed in working ship engine.Originality/value: The chemical composition of the powder was new one. Also using the laser cladding technique for ship engine parts subject of interesting.

H. Smolenska

2008-12-01

173

Performance and Exhaust Emissions in a Natural-Gas Fueled Dual-Fuel Engine  

Science.gov (United States)

In order to establish the optimum fueling in a natural gas fueled dual fuel engine, experiments were done for some operational parameters on the engine performances and the exhaust emissions. The results show that the pilot fuel quantity should be increased and its injection timing should be advanced to suppress unburned hydrocarbon emission in the middle and low output range, while the quantity should be reduced and the timing retarded to avoid onset of knock at high loads. Unburned hydrocarbon emission and thermal efficiency are improved by avoiding too lean natural gas mixture by restricting intake charge air. However, the improvement is limited because the ignition of pilot fuel deteriorates with excessive throttling. It is concluded that an adequate combination of throttle control and equivalence ratio ensures low hydrocarbon emission and the thermal efficiency comparable to diesel operation.

Shioji, Masahiro; Ishiyama, Takuji; Ikegami, Makoto; Mitani, Shinichi; Shibata, Hiroaki

174

Experimental Study on a Novel Low-temperature Automobile Exhaust Thermoelectric Generator  

Directory of Open Access Journals (Sweden)

Full Text Available To further study on Automobile Exhaust Thermoelectric Generator (AETEG, an experiment setup based on low-temperature Thermoelectric Modules (TEMs of Bi2Te3 materials, cold source of single-column cooling boxes and heat exchanger of herring-bone interior cavity was constructed. The hot source and cold source temperatures with different output powers and rotate speeds of engine were analyzed and the influences of the main operation conditions such as different contact pressures, the output currents, the output powers and rotate speeds of engine, on the maximum power and conversion efficiency were examined. The experimental results reveal that the maximum output power from the proposed AETEG setup is 179.7 W, the overall conversion efficiency at the maximum power generated from the exhaust waste heat is about 1.7%, the measures of thermal insulation and heat preservation are extraordinary important to improve the temperature differences and enhance the performance of AETEG. The meaningful results may serve as a good guide for further optimization of AETEG in next step.

Rui Quan

2013-01-01

175

Effect of hydroxy (HHO) gas addition on performance and exhaust emissions in compression ignition engines  

Energy Technology Data Exchange (ETDEWEB)

In this study, hydroxy gas (HHO) was produced by the electrolysis process of different electrolytes (KOH{sub (aq)}, NaOH{sub (aq)}, NaCl{sub (aq)}) with various electrode designs in a leak proof plexiglass reactor (hydrogen generator). Hydroxy gas was used as a supplementary fuel in a four cylinder, four stroke, compression ignition (CI) engine without any modification and without need for storage tanks. Its effects on exhaust emissions and engine performance characteristics were investigated. Experiments showed that constant HHO flow rate at low engine speeds (under the critical speed of 1750 rpm for this experimental study), turned advantages of HHO system into disadvantages for engine torque, carbon monoxide (CO), hydrocarbon (HC) emissions and specific fuel consumption (SFC). Investigations demonstrated that HHO flow rate had to be diminished in relation to engine speed below 1750 rpm due to the long opening time of intake manifolds at low speeds. This caused excessive volume occupation of hydroxy in cylinders which prevented correct air to be taken into the combustion chambers and consequently, decreased volumetric efficiency was inevitable. Decreased volumetric efficiency influenced combustion efficiency which had negative effects on engine torque and exhaust emissions. Therefore, a hydroxy electronic control unit (HECU) was designed and manufactured to decrease HHO flow rate by decreasing voltage and current automatically by programming the data logger to compensate disadvantages of HHO gas on SFC, engine torque and exhaust emissions under engine speed of 1750 rpm. The flow rate of HHO gas was measured by using various amounts of KOH, NaOH, NaCl (catalysts). These catalysts were added into the water to diminish hydrogen and oxygen bonds and NaOH was specified as the most appropriate catalyst. It was observed that if the molality of NaOH in solution exceeded 1% by mass, electrical current supplied from the battery increased dramatically due to the too much reduction of electrical resistance. HHO system addition to the engine without any modification resulted in increasing engine torque output by an average of 19.1%, reducing CO emissions by an average of 13.5%, HC emissions by an average of 5% and SFC by an average of 14%. (author)

Yilmaz, Ali Can; Uludamar, Erinc; Aydin, Kadir [Department of Mechanical Engineering, Cukurova University, 01330 Adana (Turkey)

2010-10-15

176

Method of CO sub 2 utilization in exhaust gas and power qeneration unit. Haiki gas chu no CO sub 2 riyo hoho oyobi hatsuden setsub  

Energy Technology Data Exchange (ETDEWEB)

This invention aims to prevent the global warming up by consuming CO{sub 2} in the exhaust gas in the power plant by means of a cell reaction, thus reducing the amount of CO{sub 2} emitted into the air. In other words, a power plant and a molten carbonate type fuel cell power unit are adjacently constructed which are connected to supply an exhaust gas from the power plant to a cathode of the molten carbonate fuel cell as a part of an oxidation gas. As the power output is i9ncreased by the generation by the fuel cell in addition to the generation by a gas turbine, the fuel cell power unit alone is operated during the time zone of less power demand; the gas turbine power unit is operated at a peak load. In such a xase, an exhaust gas from the power plant is supplied to the cathode of the molten carbonate fuel cell; CO{sub 2} in the above exhaust gas is consumed by the reaction at the cathode and the exhaust gas with diluted CO{sub 2} content is discharged out of the cathode. 5 figs.

Nakazawa, K. (Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan))

1991-01-01

177

40 CFR 86.1710-99 - Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and...  

Science.gov (United States)

...Fleet average non-methane organic gas exhaust...for light-duty vehicles and light light-duty...Fleet average non-methane organic gas exhaust...for light-duty vehicles and light light-duty...Fleet Average Non-Methane Organic Gas Standards...for Light-Duty Vehicles and Light...

2010-07-01

178

Pilot plant experiment on the treatment of exhaust gas from a sintering machine by electron beam irradiation  

Energy Technology Data Exchange (ETDEWEB)

Research report: Described is a one-year study by the Ebara Corp. of Japan that verified the performance of the electron beam irradiation process for exhaust gas treatment. The process was used to treat exhaust gas from a sintering machine at a steel pilot plant with a capacity of 3000 cu nm/hr. Experimental data collected during the one year test period, one month of which involved the continuous operation of the process, are discussed. The method was shown to remove nitrous oxides and sulfur oxides from the exhaust gas of a sintering machine. NOx removal of about 80% and SOx removal of more than 95% both were obtained steadily during the period of one month continuous operation. (1 diagram, 8 graphs, 14 references, 1 table)

Kawamura, K.; Aoki, S.; Kimura, H.; Kengaku, K.; Adachi, K.; Sawada, Y.; Kawamura, K.

1980-03-01

179

Combustion and exhaust emission characteristics of a dual fuel compression ignition engine operated with pilot Diesel fuel and natural gas  

International Nuclear Information System (INIS)

Towards the effort of reducing pollutant emissions, especially soot and nitrogen oxides, from direct injection Diesel engines, engineers have proposed various solutions, one of which is the use of a gaseous fuel as a partial supplement for liquid Diesel fuel. These engines are known as dual fuel combustion engines, i.e. they use conventional Diesel fuel and a gaseous fuel as well. This technology is currently reintroduced, associated with efforts to overcome various difficulties of HCCI engines, using various fuels. The use of natural gas as an alternative fuel is a promising solution. The potential benefits of using natural gas in Diesel engines are both economical and environmental. The high autoignition temperature of natural gas is a serious advantage since the compression ratio of conventional Diesel engines can be maintained. The present contribution describes an experimental investigation conducted on a single cylinder DI Diesel engine, which has been properly modified to operate under dual fuel conditions. The primary amount of fuel is the gaseous one, which is ignited by a pilot Diesel liquid injection. Comparative results are given for various engine speeds and loads for conventional Diesel and dual fuel operation, revealing the effect of dual fuel combustion on engine performance and exhaust emissions

2004-11-01

180

Exhaust gas emissions and mutagenic effects of modern diesel fuels, GTL, biodiesel and biodiesel blends  

Energy Technology Data Exchange (ETDEWEB)

Biodiesel can be used alone (B100) or blended with petroleum diesel in any proportion. The most popular biodiesel blend in the U.S.A. is B20 (20% biodiesel, 80% diesel fuel), which can be used for Energy Policy Act of 1992 (EPAct) compliance. In the European Union, the use of biofuel blends is recommended and was introduced by federal regulations in several countries. In Germany, biodiesel is currently blended as B5 (5% biodiesel) to common diesel fuel. In 2008, B7 plus three percent hydrotreated vegetable oil (HVO) as well is intended to become mandatory in Germany. To investigate the influence of blends on the emissions and possible health effects, we performed a series of studies with several engines (Euro 0, III and IV) measuring regulated and non-regulated exhaust compounds and determining their mutagenic effects. Emissions of blends showed an approximate linear dependence on the blend composition, in particular when regulated emissions are considered. However, a negative effect of blends was observed with respect to mutagenicity of the exhaust gas emissions. In detail, a maximum of the mutagenic potency was found in the range of B20. From this point of view, B20 must be considered as a critical blend, in case diesel fuel and biodiesel are used as binary mixtures. (author)

Munack, Axel; Ruschel, Yvonne; Schroeder, Olaf [Federal Research Institute for Rural Areas, Forestry and Fisheries, Braunschweig (Germany)], E-mail: axel.munack@vti.bund.de; Krahl, Juergen [Coburg Univ. of Applied Sciences (Germany); Buenger, Juergen [University of Bochum (Germany)

2008-07-01

 
 
 
 
181

Simultaneous removal of NO(x) and SO2 in exhausted gas through landfill leachate.  

Science.gov (United States)

Simultaneous removal of NO(x) and SO2 from exhausted gas were investigated by studying co-culture of sulfate reducing bacteria and anaerobic denitrifying bacteria, separated from landfill leachate. When H2S, generated by sulfate reducing bacteria was chosen as the sole electron donor for anaerobic denitrifying bacteria, the co-culture system demonstrated a faster NO removal rate, higher stability and better permanence. When the feed gas flow rates of N2 and SO2 were maintained constant at 0.1 m3/h and 16 ml/min respectively, the maximum NO-removal rate could be achieved at over 92% with NO feed gas kept between 2-6 ml/min, while the SO2 removal rate was always above 95%. Long-term continuous removal of NO exhibited an evident periodicity of five days, however, the fluctuation range of NO-removal was decreasing. Moreover, the decrease of the gas flow rate and the increase in NO inlet concentration could contribute to a higher NO- removal rate. PMID:21250607

Han, Yaqiong; Zhang, Weijiang

2010-12-01

182

NOx remediation in oxygen-rich exhaust gas using atmospheric pressure non-thermal plasma generated by a pulsed nanosecond dielectric barrier discharge  

International Nuclear Information System (INIS)

It is clearly seen that the application of non-thermal plasmas (NTP) to remove NOx from gas mixture containing a large amount of oxygen (O2) is dominated by NO to NO2 oxidation. Experiments have been conducted using a NTP generated by a nanosecond pulsed dielectric barrier discharge in synthetic exhaust gas, prepared from N2, O2, NO, H2O, and C3H6, over a large range of gas temperature (20-300 deg. C). Results show that the NOx removal rate significantly increased with increasing specific energy deposition. For example, at a temperature of 100 deg. C and an energy deposition of 27 J l-1, 92% of the NO molecules have been removed. The W values for NO is dramatically reduced to values scaling from approx. 15 eV at 27 J l-1 down to approx. 4 eV at 7 J l-1. NOx removal efficiency around 43% was obtained at a temperature of 260 deg. C and a space velocity of 60 000 h-1 for a specific input energy of 27 J l-1. W values for NOx were less than approx. 30 eV. Such treatments in exhaust gas with and without the presence of water vapour induced reactions leading to the production of a large variety of by-products such as acetaldehyde, propylene oxide, formic acid, methyl nitrate, and nitromethane. (author)

2002-07-07

183

Infiltration of engine exhaust into natural gas-fired compressor stations  

Energy Technology Data Exchange (ETDEWEB)

Nitrogen oxides concentrations were measured inside buildings at two natural gas fired compressor engine stations. Average concentrations as high as 1.12 mg/m/sup 3/ NO/sub 2/ 11.4 mg/m/sup 3/ NO were found in the main engine buildings. Data on indoor concentration, engine emissions, ventilation and infiltration were evaluated with a pollutant mass balance model. The modeling results show that up to 4% of the total engine emission at the two stations studied can infiltrate back inside the main engine building. Exhaust stacks located adjacent to the engine building were only half of the building height. Stack downwash and pollutant trapping in the turbulent zones around the buildings is, therefore, the likely cause of the elevated indoor concentrations.

Scheff, P.A.; Guidarelli-Hurley, M.

1987-08-01

184

Simplified prediction of soot emissions in the exhaust of gas turbines operated at atmospheric pressure  

International Nuclear Information System (INIS)

In previous works [1, 2], a correlation for the prediction of soot in gas turbine exhaust has been presented. The development of the correlation is based on 300 of experimental data for a total of 19 fuels burned both at atmospheric and high pressure (0.1 to 0.9 MPa) and two scales (1/2 and 1/3) of a Laval type combustion chamber. With the wide range of fuels burned in the experiment giving a smoke number variation from 0 to 100, the accuracy of the correlation (Standard Deviation of 40%) is acceptable for most purposes Later on the correlation has been improved using data from the full scaled combustion chamber as shown in [3]. A detailed analysis of the correlation is undertaken within the present work for the case of the experiments at atmospheric pressure. The result is a simplification of the correlation presented in [3] without a major deterioration of the standard deviation. This result leads to a simplification of the previous proposed soot formation and oxidation model within gas turbine combustors (operated at atmospheric pressure) and limits the analysis of the phenomenon on essential functional parameters as well. Gas turbines are generally used in aircraft, ships, and in stationary production of electricity, heat and vapor. (author)

2010-01-01

185

Analysis of exhaust gas composition of internal combustion engines using liquefied petroleum gas  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The problems of implementation of liquefied petroleum gas (LPG) supply systems are related with the fact that they are alternative systems used in engines constructed and optimized for work with other kinds of fuel. So assemblers of the systems have to evaluate power losses and at the same time ecological requirements. The experiment is devoted to the analysis of gas composition of engines working at different modes in order to specify the particularity of LPG system tuning and to obtain data...

Mockus, Saulius; Sapragonas, Jonas; Stonys, Agnius; Pukalskas, Saugirdas

2006-01-01

186

40 CFR 86.109-94 - Exhaust gas sampling system; Otto-cycle vehicles not requiring particulate emission measurements.  

Science.gov (United States)

...Light-Duty Trucks and New Otto-Cycle Complete Heavy-Duty Vehicles...gas sampling system; Otto-cycle vehicles not requiring particulate...the exhaust of either Otto-cycle light-duty vehicles or...total volume is measured by counting the revolutions made by...

2010-07-01

187

Fuel compositions and additive mixtures containing carboxymethoxy propanedioic acid esters for alleviation of exhaust gas catalyst plugging  

Energy Technology Data Exchange (ETDEWEB)

A gasoline is described for an internal combustion engine having a cyclopentadienyl manganese tricarbonyl antiknock compound and a compound to reduce plugging of an exhaust gas catalyst. The general chemical composition of the compound and options for various radicals are discussed.

Gautreaux, M.F.

1975-07-07

188

Process for neutralization, particularly of exhaust-gas condensate from combustion boilers. Verfahren zur Neutralisation insbesondere von Abgaskondensat aus Brennwertkesseln  

Energy Technology Data Exchange (ETDEWEB)

In a process for neutralizing the condensate or other aqueous solutions, particularly for neutralizing the exhaust gas condensate from combustion boilers, a solution is to be created by which neutralization is possible without the use of solid or liquid means of neutralization for treating condensates. This is achieved by treating the condensate electrochemically.

Rickert, H.; Holzaepfel, G.; Baeumler, H.; Mueller, P.

1985-07-04

189

Numerical model of a thermoelectric generator with compact plate-fin heat exchanger for high temperature PEM fuel cell exhaust heat recovery  

DEFF Research Database (Denmark)

This paper presents a numerical model of an exhaust heat recovery system for a high temperature polymer electrolyte membrane fuel cell (HTPEMFC) stack. The system is designed as thermoelectric generators (TEGs) sandwiched in the walls of a compact plate-fin heat exchanger. Its model is based on a finite-element approach. On each discretized segment, fluid properties, heat transfer process and TEG performance are locally calculated for higher model precision. To benefit both the system design and fabrication, the way to model TEG modules is herein reconsidered; a database of commercialized compact plate-fin heat exchangers is adopted. Then the model is validated against experimental data and the main variables are identified by means of a sensitivity analysis. Finally, the system configuration is optimized for recovering heat from the exhaust gas. The results exhibit the crucial importance of the model accuracy and the optimization on system configuration. Future studies will concentrate on heat exchanger structures.

Xin, Gao; Andreasen, Søren Juhl

2012-01-01

190

CO{sub 2} separation from exhaust gas; CO{sub 2} separasjon fra eksosgass  

Energy Technology Data Exchange (ETDEWEB)

When Saga wanted to reduce the CO{sub 2} emissions from Snorre B, cleaning of CO{sub 2} from exhaust gas was one of several options considered. CO{sub 2} cleaning using membrane/amine technology is under development. Saga required that the technology should be qualified and that the yield of the Snorre B project should not be reduced. This presentation discusses qualification of combined membrane/amine technology, environmental issues, economic issues and implementation on the Snorre B platform. Flue gas from the gas turbine is passed to a CO{sub 2} absorption and desorption stage from which the CO{sub 2} is passed on for compression and disposal while the cleaned flue is let out. The membrane is situated between the flue gas and the absorbent liquid. The pores are large enough for the CO{sub 2} to pass through quickly and small enough to prevent the liquid from penetrating into the pores. The packing factor is high, 500 - 1000 m2/m3, there is no formation of froth, ducts or entrainment of the liquid. New technology implies 65 - 70% size reduction of the main equipment and 39 - 40% reduction of the energy consumption. Research on amines brings out new chemicals which imply 80% reduction in the consumption of chemicals and the quantity of special waste produced. If a CO{sub 2} cleaning plant is installed on a LM 2500, the CO{sub 2} emissions can be reduced by 97,200 ton/year given the right operational conditions. Although it was decided in 1998 not to install the module with the CO{sub 2} pilot cleaning plant, Snorre B is still a good environmental project having CO{sub 2} emission within the values set by Miljoesok.

Magelssen, Paul Fr. [Saga Petroleum A/S, Forus (Norway)

1998-07-01

191

Tritium Recovery at Fusion Facility 6.Development of Exhaust Gas and Effluent Liquid Treatment System for LHD  

Science.gov (United States)

In order to realize deuterium plasma control experiments using the Large Helical Device(LHD), NIFS is planning to install a tritium recovery system for use on exhaust gas and effluent liquid. Besides applying the conventional and proved recovery system, NIFS has made development plans for implementation of a compact and less waste generating recovery system by applying the latest technologies such as tritiated water vapor removal with a membrane type dehumidifier and tritium gas extraction with a proton conducting cell.

Asakura, Yamato

192

Numerical Simulation of Exhaust Gas Cooling in Channels with Periodic Elbows for Application in Compact Heat Recovery Systems  

International Nuclear Information System (INIS)

Miniature and Micro devices represent the new frontier for advanced heat and mass transfer technology. Due to the small length scales, the use of CFD is very useful for designing and optimizing microfluidic devices since experimentation and visualization at these scales can be difficult. In this work a high temperature air microfluidic cooling strategy for applications such as compact waste heat recovery, exhaust gas recirculation and fuel cell thermal management is proposed. Initially, the application of a simple straight microchannel is considered. In an effort to partially compensate for the poor thermal properties of air, right-angle bends are introduced in order to induce Dean vortices which periodically restart the thermal boundary layer development, thus improving the heat transfer and fluid mixing. Numerical simulations in the range of 100 ? ReDh ? 1000 have been carried out for channels of square cross-section. Channel wall lengths of 1.0 mm are investigated for elbow spacings of 5 mm, 10 mm and 15 mm. High temperature air (300°C) at atmospheric inlet pressure is the working fluid. The results indicate that the elbows substantially improve the local and average heat transfer in the channels while increasing the pressure drop. Design considerations are discussed which take into account the heat transfer and pressure drop characteristics of the channels.

2012-11-26

193

Possibilities and limitations of exhaust gas analysis for expanded use in control of an AOD-converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The main purpose of the AOD-converter is to lower the carbon content in stainless steel production. The carbon content can be estimated by static theoretical models. It can also be estimated through dynamic models based on analysis of the exhaust gases from the converter. This master thesis is a study on an extended use of exhaust gas analysis data on the AOD-converter at Outokumpu’s stainless steel plant in Avesta, Sweden. There are two main methods of predicting the carbon content based o...

Laxe?n, Jonas

2012-01-01

194

On exhaust emissions from petrol-fuelled passenger cars at low ambient temperatures  

Energy Technology Data Exchange (ETDEWEB)

The study at hand deals with regulated and unregulated exhaust emissions from petrol-fuelled cars at low ambient temperatures with present-day or near-future exhaust after treatment systems. The subject has been investigated at VTT over a decade and this report compiles data from various sub-studies carried out between the years 1993 - 1997. Each one of them viewed different aspects of the phenomenon, like determining the low-temperature response of today`s new cars employing three-way catalytic converters or assessing the long-term durability and the influence of vehicle mileage upon the low-temperature emissions performance. Within these studies, together more than 120 cars of model years from 1990 to 1997 have been tested. Most of them were normal, in-service vehicles with total mileages differing between only a few thousand kilometres for new cars up to 80,000 km or even more for the in-use vehicles. Both the US FTP75 and the European test cycle have been employed, and the ambient temperatures ranged from the baseline (+22 deg C) down to +- O deg C, -7 deg C and in some cases even to -20 deg C. The studies attested that new cars having today`s advanced emissions control systems produced fairly low levels of emissions when tested in conditions designated in the regulations that are the basis of the current new-vehicle certification. However, this performance was not necessarily attained at ambient temperatures that were below the normative range. Fairly widespread response was recorded, and cars having almost equal emissions output at baseline could produce largely deviating outcomes in low-temperature conditions. On average, CO and HC emissions increased by a factor of five to 10, depending on the ambient temperature and vehicle type. However, emissions of NO{sub x} were largely unaffected. Apart from these regulated emissions, many unregulated species were also determined, either by using traditional sampling and chromatography methods or on-line, employing the latest FTIR technology. Overall, the levels of these emissions were also mostly elevated at subnormal temperatures. Total vehicle mileage seemed not to affect cold-start emissions (CO and HC) at low temperatures. Nor did the overall durability of the emission control system appear to be worse in cold-climate conditions typical for Finland. The deterioration of the emissions performance in the tested vehicles either closely followed the average trend defined by the normal, assigned deterioration factors or was even lesser. The conclusions of this report underline the necessity of a separate low-temperature test in order to really effectively curb real-world emissions. Standards at normal temperature are no more effective alone, but need to be accompanied with additional requirements for good performance also in conditions closer to the everyday use, which comprises many cold-starts even in low ambient temperature conditions. (orig.) 75 refs.

Laurikko, J. [VTT Energy, Espoo (Finland). Energy Use

1998-11-01

195

A wind-tunnel study on exhaust-gas dispersion from road vehicles. Part 2. Effect of vehicle queues  

Energy Technology Data Exchange (ETDEWEB)

By a reduced-scale wind-tunnel experiment, we investigate the dispersion behavior of exhaust gas from automobiles. Based on the results of single-vehicle cases in Part I of our work, we consider vehicle queues consisting of passenger cars (P) and small-size trucks (T). The roles of the vehicles before and after the gas-emitting vehicle are as follows. By their turbulent wake, the preceding vehicles make the concentration field approximately symmetric in the spanwise direction despite the significant lateral offset of the exhaust pipe. The vehicles behind the gas-emitter expand the exhaust plume considerably in the spanwise direction; T expands the plume also in the vertical direction in its roll-up wake, while P scoops up the oncoming plume only around the centerline. For vehicle queues of mixing ratio P:T=2:1, the concentration fields when one of the component vehicles emit the gas are measured. It turns out that the plume shape is determined mostly by the type of the gas-emitting vehicle whereas the type of the following vehicles has minor effect. We also present an analytical procedure to approximate the overall contribution from all the queue-forming vehicles by a Gaussian line-source plume formula. (author)

Kanda, Isao; Uehara, Kiyoshi; Yamao, Yukio [National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506 (Japan); Yoshikawa, Yasuo; Morikawa, Tazuko [Petroleum Energy Center, 4-3-9 Toranomon, Minato-ku, Tokyo 105-0001 (Japan)

2006-09-15

196

Study of an exhaust gas recirculation equipped micro gas turbine supplied with bio-fuels  

International Nuclear Information System (INIS)

The authors discuss in this paper some aspects related to the employment of liquid and gaseous bio-fuels in a micro-gas turbine. Besides the purpose of checking the effectiveness of methods for supplying the micro-turbine with fuels from renewable sources, the attention is focused on the need of controlling the pollutant emission. To this aim, several solutions are experienced and numerically tested. For the liquid fuel supply, a new shape and location of the main fuel injector is combined with a modified position of the pilot injector. In the case of the biogas fuelling, an external EGR option is considered as activated. Both methods aim at the reduction of the thermal and prompt NO formation by approaching the flameless combustion concept. -- Highlights: • External and internal EGR concepts applied to NOx control from micro gas turbines. • For gaseous fuels: internal EGR is obtained by a proper location of the pilot injector. • For liquid fuels: replacing the original radial injectors with a pressure swirl atomizer. • We apply a CFD based method, after validation with experimental data. • Blends of bio-fuels with fossil fuels promise noticeable benefits

2013-09-25

197

COMBINED IMPACT OF BIODIESEL (MENO AND EXHAUST GAS RECIRCULATION ON NOX EMISSIONS IN DI DIESEL ENGINES  

Directory of Open Access Journals (Sweden)

Full Text Available The steep rises in the prices of the petroleum fuels and the concern for the environment have forced the researchers to find alternative renewable fuels which are called bio-fuels. The objective of this work is to find the optimum EGR and biodiesel blend matrix for the better performance and optimum emission reduction in a DI diesel engine. The bio fuel used in the experimentation is derived from the Neem oil. A twin-cylinder, air-cooled, constant speed direct injection diesel engine is used for experiments. HC, NOx, CO, and smoke of the exhaust gas are measured. Various engine performance parameters such as thermal efficiency, and brake specific fuel consumption are calculated from the acquired data. As the percentage of bio diesel increased in diesel and bio fuel blend the NOx emission increased. In order to reduce the emission from bio diesel EGR is used. Application of EGR with biodiesel blends resulted in reductions in NOx emissions without any significant penalty in smoke emissions. The results reveal that the Blend 100 (100 % bio fuel produces maximum NOx emission (300 ppm. With 25% volume flow rate of EGR with the same B100 bio diesel, the NOx emission is reduced approximately 300 ppm to 100 ppm

B. Jothithirumal

2012-09-01

198

Establishing isokinetic flow for a plasma torch exhaust gas diagnostic for a plasma hearth furnace  

Energy Technology Data Exchange (ETDEWEB)

Real time monitoring of toxic metallic effluents in confined gas streams can be accomplished through use of Microwave Induced Plasmas to perform atomic emission spectroscopy, For this diagnostic to be viable it is necessary that it sample from the flowstream of interest in an isokinetic manner. A method of isokinetic sampling was established for this device for use in the exhaust system of a plasma hearth vitrification furnace. The flow and entrained particulate environment were simulated in the laboratory setting using a variable flow duct of the same dimensions (8-inch diameter, schedule 40) as that in the field and was loaded with similar particulate (less than 10 {mu}m in diameter) of lake bed soil typically used in the vitrification process. The flow from the furnace was assumed to be straight flow. To reproduce this effect a flow straightener was installed in the device. An isokinetic sampling train was designed to include the plasma torch, with microwave power input operating at 2.45 GHz, to match local freestream velocities between 800 and 2400 ft/sec. The isokinetic sampling system worked as planned and the plasma torch had no difficulty operating at the required flowrates. Simulation of the particulate suspension was also successful. Steady particle feeds were maintained over long periods of time and the plasma diagnostic responded as expected.

Pollack, B.R.

1996-05-01

199

Reducing the CO2 emissions from fossil fuel power plans by exhaust gas treatment  

International Nuclear Information System (INIS)

The emission of carbon dioxide (CO2) and other pollutants which result from burning fossil fuels has been identified as the major contributor to global warming and climate change. However, for the short term, at least for the next 10-20 years, the world will continue to rely on fossil fuels as the source of primary energy. The challenge for the fossil the fuel industry is to find cost-effective solutions that will reduce the release of CO2 and other pollutants into the atmosphere. The focus of this paper is on the ability to treat the exhaust gas from fossil fuel power plants in order to capture and store the CO2 and remove the other pollutants such as SOx and NOx which are released into the atmosphere. In summary, capture/separation costs represent the largest financial impediment for this type of plants. Hence, efficient, cost-effective capture/separation technologies need to be developed to allow their large-scale use. (author)

2007-01-01

200

Soot burning in exhaust gas economizer of diesel ship. Diesel sen hai gas economizer no soot nensho  

Energy Technology Data Exchange (ETDEWEB)

Investigations were made on soot burning in exhaust gas economizer (EGE) in groups of finned tubes of a diesel ship. A soot burning simulation model was structured to elucidate soot fire mechanism. Since the calculation result has not conflicted with empirical features in soot fire failures in actual ships, the simulation is thought to have simulated actual soot burning processes to some extent. According to the result, if soot accumulated in the EGE gets ignited somewhere, it results in less occasion that the combustion spreads downstream. In this case, the more downstream the heat transferring face, and the more the number of stages, the effect of the soot combustion increases. The factor of fire spreading from an ignition point is influenced largely by the heat transfer rates inside the tubes (water side) and outside the tubes (gas side). With respect to possibility of leading to a soot fire accident, that is a melt-down, intra-tube heat transfer gives a decisive effect. Occurrence of soot combustion increases heat load in the particular tubes to 1.5 to two times that at normal operation. 4 refs., 9 figs.

Nishikawa, E. (Kobe University of Mercantile, Marine, Kobe (Japan)); Kawamura, K. (Takuma Co. Ltd., Osaka (Japan))

1993-06-01

 
 
 
 
201

Reformulation of engine gasoline to reduce exhaust emissions in Finnish conditions. Effect of gasoline aromatics, olefins and T90 temperature on exhaust emissions; Moottoribensiinin reformulointi paeaestoejen vaehentaemiseksi Suomen oloissa. Bensiinin aromaattien, olefiinien ja T90-laempoetilan vaikutus paeaestoeihin  

Energy Technology Data Exchange (ETDEWEB)

The research work focused on the effects of gasoline composition, i.e. aromatics and olefin contents and 90 % point of distillation, on exhaust emissions. The experimental part comprised exhaust gas measurements for 13 catalyst cars at +22 deg C and for one non-catalyst car at +22 deg C according to FTP75 driving cycle. Regulated emissions (THC, CO and NO{sub x}), non-regulated emissions (hydrocarbons and aldehydes), carbon dioxide and fuel consumption were measured. The high aromatics contents of eight test fuels were about 40 vol% and the low ones about 15 vol%, the high olefin contents were about 15 vol% and the low ones about 2 vol%, and the high T90 temperatures about +170 deg C and the low ones +145 deg C. The results were treated in two ways: effects of each single change in characteristics, and those of simultaneous changes in all fuel characteristics studied. The lowest CO and THC emissions for the catalyst cars at +22 deg C were obtained by reducing the aromatics content and the T90 temperature of the fuel, while the reduction of the olefin content increased respective emissions. The NO{sub x} emission increased when the aromatics content and T90 temperature were reduced, and decreased slightly when the olefin content was reduced. The CO{sub 2} emission and the fuel consumption (kg/100 km) were affected, i.e. reduced, only by a reduction in the aromatics content. However, the fuel consumption in volume units (1/100 kg) increased. The results at -7 deg C for THC and NO{sub x} emissions were along the same lines as at +22 deg C, except for the CO emission, which decreased when the olefin content was reduced and increased when the T90 temperature was lowered

Aakko, P.; Kytoe, M. [VTT Energy, Espoo (Finland). Energy Use; Kokko, J.; Rantanen, L.; Karintaus, A.; Pentikaeinen, J. [Neste Oy, Espoo (Finland)

1995-12-31

202

Combined device for making use of exhaust gas energy to drive internal combustion engines and to reduce the CO and CH content of the exhaust gas of these engines and a device for further detoxification of the exhaust gas integrated with this device. Kombinationseinrichtung zur Nutzbarmachung der Abgasenergie als Antriebskraft bei Verbrennungskraftmaschinen und zur Senkung des CO und CH-Gehaltes im Abgas dieser Maschinen, sowie eine in diese mit integrierte Einrichtung zur weiteren Entgiftung des Abgases  

Energy Technology Data Exchange (ETDEWEB)

This is a combined device for making use of the exhaust gas energy to drive internal combustion engines, which works by the combined effect of a gas drive unit in the form of a turbine rotor, which is supplied with the exhaust gas of a rotating piston engine, and in whose range of operation, by supplying air to the gas flow, there is further post-combustion with simultaneous reduction of the CO and CH content in the exhaust gas and the exhaust gases are then removed via a catalyst for further detoxification, where the load transfer to the gearbox clutch is either direct or combined with a freewheel connected to the engine shaft.

Stanek, W.; Stanek, F.

1986-04-03

203

Formaldehyde in the exhaust gas of biogas engine plants and natural gas cogeneration plants; Formaldehyd im Abgas von Biogasmotoranlagen und Erdgas-Blockheizkraftwerken  

Energy Technology Data Exchange (ETDEWEB)

The pricing regulations of the Renewable Energy Law EEG 2009 enabled the operation of biogas facilities within the agricultural range. The emissions of formaldehyde in the exhaust gas are regarded with respect to the future limiting values with biogas combustion engine plants.

Ebertsch, Gerald [Bayerisches Landesamt fuer Umwelt, Augsburg (Germany); Fiedler, Alexander [Regierung von Oberbayern, Muenchen (Germany)

2010-07-01

204

New Temperatures of Diffuse Interstellar Gas: Thermally Unstable Gas  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We present new Arecibo 21-cm line measurements of the temperatures of interstellar gas. Our temperatures for the Cold Neutral Medium (CNM) are significantly lower than previous single-dish results and in very good accord with theoretical models. For warm gas at T > 500 K, we find a significant fraction of gas (>47%) to lie in the thermally unstable region 500 ---> 5000 K; moreover, about 60% of all the neutral atomic gas has T > 500 K. Large amounts of thermally unstable gas...

Heiles, Carl

2001-01-01

205

A wind-tunnel study on exhaust gas dispersion from road vehicles. Part 1. Velocity and concentration fields behind single vehicles  

Energy Technology Data Exchange (ETDEWEB)

By a reduced-scale model in a wind tunnel, we investigate the dispersion behavior of exhaust gas from automobiles. Two types of vehicles are considered, a passenger car and a small-size truck. Tracer gas experiments show that the exhaust gas dispersion is enhanced significantly by the vehicle wake compared to the case when the vehicle body is absent. The passenger car and the truck promote dispersion in the horizontal and the vertical direction, respectively. The wake field is analyzed by particle image velocimetry (PIV), and the distribution of the mean and the fluctuation fields is found to conform to the concentration field of the exhaust gas. The buoyancy of the exhaust gas has minor effect except on the vertical spread behind the truck whose wake flow amplifies the vertical displacement generated near the pipe exit. (author)

Kanda, Isao; Uehara, Kiyoshi; Yamao, Yukio [National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, 305-8506 (Japan); Yoshikawa, Yasuo; Morikawa, Tazuko [Petroleum Energy Center, 4-3-9 Toranomon, Minato-ku, Tokyo, 105-0001 (Japan)

2006-09-15

206

A laboratory test unit for exhausted gas cleaning by electron beam and combined electron beam-microwave irradiation  

Energy Technology Data Exchange (ETDEWEB)

At the electron accelerator laboratory, NILPR, Bucharest developed a small laboratory test unit (max. gas flow rate = 1 Nm{sup 3}/h) for exhaust gas cleaning by means of electron beam and combined electron beam microwave irradiation. The aim of these methods is to obtain the concomitant removal of the NO{sub x} and SO{sub 2} by precipitation with ammonia. Several parameters such as residence time and dose, reaction temperature, argon and NH{sub 3} concentration, etc. were investigated. The removal efficiencies were: only for electron beam irradiation 63-80% for SO{sub 2} and 0-63% for NO{sub x}; for combined electron beam-microwave treatment 68-95% for SO{sub 2} and 0-70% for NO{sub x}. Also, the presence of a small concentration of argon in the irradiated gaseous mixture increases the SO{sub 2} removal efficiency (between 5% and 10%) for both electron beam and electron beam-microwave treatment. As electron beams generator was used the Linear Accelerator ALID-7 (5.5 MeV, 670 W). The microwave applicator consists of a power-controlled generator with a 2.45 GHz magnetron of 850 W maximum output power, a launcher to fit to waveguide WR430, a dual directional coupler and a three stub tuner for impedance matching. Our tests also demonstrated that the combined method electron beam-microwave irradiation, due to the additional use of microwave energy, leads to the decrease of the electron beam average power from 30% to 50%, at the same removal efficiency. (orig.) 8 refs.

Radoiu, M.; Martin, D.; Bestea, V.; Indreias, I.; Matei, C. [Inst. for Atomic Phys., Bucharest (Romania). Electron Accel. Lab.; Georgescu, I.I.; Calinescu, I. [Polytechnic University of Bucharest, Chemical Engineering Faculty, Calea Grivitei 132, 78122 Bucharest (Romania)

1998-04-01

207

Influence of an Optimized Thermoelectric Generator on the Back Pressure of the Subsequent Exhaust Gas System of a Vehicle  

Science.gov (United States)

Numerous research projects in automotive engineering focus on the industrialization of the thermoelectric generator (TEG). The development and the implementation of thermoelectric systems into the vehicle environment are commonly supported by virtual design activities. In this paper a customized simulation architecture is presented that includes almost all vehicle parts which are influenced by the TEG (overall system simulation) but is nevertheless capable of real-time use. Moreover, an optimized planar TEG with minimum nominal power output of about 580 W and pressure loss at nominal conditions of 10 mbar, synthesized using the overall system simulation, and the overall system simulation itself are used to answer a generally neglected question: What influence does the position of a TEG have on the back pressure of the subsequent exhaust gas system of the vehicle? It is found that the influence of the TEG on the muffler is low, but the catalytic converter is strongly influenced. It is shown that the TEG can reduce the back pressure of an exhaust gas system so much that its overall back pressure is less than the back pressure of a standard exhaust gas system.

Kühn, Roland; Koeppen, Olaf; Kitte, Jens

2014-06-01

208

*GAS-PHASE AND PARTICULATE COMPONENTS OF DIESEL EXHAUST PRODUCE DIFFERENTIAL CARDIOPHYSIOLOGICAL IMPAIRMENTS IN HEALTHY RATS  

Science.gov (United States)

We recently showed that inhalation exposure of normotensive Wistar Kyoto (WKY) rats to whole diesel exhaust (DE) elicited changes in cardiac gene expression pattern that broadly mimicked gene expression in non-exposed spontaneously hypertensive rats. We hypothesized that healthy ...

209

The influence of light diesel fuel on diesel exhaust gas emission  

Energy Technology Data Exchange (ETDEWEB)

Seven different diesel fuels were tested in order to investigate the influence of fuel properties on exhaust gas emission. A Volvo bus engine was used for 13-mode tests, and three buses (Volvo, Scania and Leyland) were used for measurements of particulates during 30 seconds of acceleration. In addition particulates were measured during the start up of the Volvo every morning. The 13-mode test was carried out using one filter per mode which gives more detailed results. The results of the 13-mode test are shown as an increase in emission relative to Shell commerc, diesel. Measurements during acceleration and cold start showed the same tendency for the particulate emission. The first four fuels tested gave emissions at the same level. Shell Diesel LE and Swedish Light Diesel. Use of Synth. fuel (D 70) resulted in a reduction of the maximum engine power, therefore adjustments of the injection pump were necessary but extensive reduction of especially particulate emission was measured. Shell Diesel LE and Swedish Light Diesel can be produced in sufficient quantity to cover the need for the buses in Copenhagen, While Synth. fuel (D 70) cannot be produced in Denmark. Proces per kWh relative to Shell Commercial diesel are estimated in September 1990 for a limited fuel volume as used in Copenhagen. If more fuel is needed, changes in the refineries are necessary and the price is no longer valid. An economical emission factor is given the lower the value, the more economical is the emission reduction. Research showed that emission can be achieved when the correct fuel is chosen. Changes in the refinery technique would be advantageous. (AB).

Frodl, B.; Ezerman, N.; Bak, F.

1990-10-15

210

Exhaust temperature increase and soot loading control: key issues for Diesel particulate filter regeneration; Abgastemperaturerhoehung und Russbeladungskontrolle: Schluesselpunkte fuer die Regeneration von Dieselpartikelfilter  

Energy Technology Data Exchange (ETDEWEB)

Diesel particulate filter technology turns out to be highly efficient in reducing the amount of particulate matter in Diesel exhaust gas. However, the requirement for safe and reliable regeneration technologies has, so far, strongly limited the commercial diffusion of Diesel Particulate Filters. Todays light-duty Diesel exhaust gas temperatures tend to decrease, which makes the regeneration process more difficult. Fortunately, the engine management systems required by the new high pressure injection technologies make it possible to create and control an exhaust temperature increase. For example, modification of injection timing, EGR rate, or boosting pressure can lead to an average 150 C exhaust temperature increase. In addition, a catalyst located close before the filter, associated with fuel post-injection, enables a further temperature increase of about 250 C. These strategies combined with the use of fuel borne additive enable filter regeneration between 380 C and 450 C under all engine load conditions. The strategies initially developed at the engine test bed level have been since implemented on a vehicle fitted with an IFP engine management system. Another key issue is the optimisation of the regeneration frequency in order to improve the fuel consumption as well as the thermal ageing of the filter. In that regard, a sooting sensor has been developed, enabling an accurate regeneration triggering as well as a trap failure detection. It represents a valuable alternative to common filter pressure drop measurement. (orig.) [German] Die Dieselpartikelfiltertechnologie erweisst sich als sehr leistungsfaehig um Partikel aus den Dieselabgasen zu entfernen. Die Vermarktung dieser Technologie ist jedoch auf Grund der Schwierigkeit einer betriebssicheren Regenerationskontrolle zur Zeit noch sehr begrenzt. Einerseits macht die heutige Tendenz zu niedrigeren Abgastemperaturen fuer Pkws die Filterregeneration schwieriger, andersseits ermoeglicht die fuer die neuen Hochdruckeinspritzungssysteme notwendigen Motorsteuerungen neue Strategien um Abgastemperaturen zu erhoehen. Zum Beispiel fuehren die Veraenderungen von Einspritzungszeit, Abgasrueckfuehrung, oder Aufladung zu einer Temperaturerhoehung von ungefaehr 150 C. Mit Hilfe von einem vor dem Filter eingebauten Oxidationskatalysator und von einer Nacheinspritzungsstragegie ist eine weitere Temperaturerhoehung von 250 C bis 300 C moeglich. In Verbindung mit Kraftstoffadditiven ermoeglichen diese Strategien eine Filterregeneration zwischen 380 C und 450 C unter alle Motorbedingungen. Die am Motorpruefstand entwickelten Strategien wurden durch eine IFP Motorsteuerung, in einem Pkw eingebaut. Ein weiterer Schluesselpunkt ist die Optimierung der Regenerationsfrequenz, um Kraftstoff zu sparren und das thermische Verhalten des Filters zu sichern. Ein Russbeladungssensor wurde entwickelt, der das genaue Einschalten der Regenerationsphase verbessern kann. Dieser Sensor ist eine gute Alternative zur Filtergegendruckmessung. Es ist jedoch auch moeglich Filterbruch und andere Stoerungen zu erkennen. (orig.)

Bouchez, M.; Dementhon, J.B. [IFP, Paris (France)

2000-07-01

211

High temperature gas cooled reactor  

International Nuclear Information System (INIS)

Purpose: To provide a pebble bed type high temperature gas cooled reactor adapted for use of plutonium fuel. Constitution: A fuel sphere filled in a reactor core consists of a central fuel region and an outside graphite moderator region. The fuel region further consists of an inside fuel region made of graphite as base material and coating fuel particles of plutonium oxide in slight amount added thereto, and an outside thin layer fuel region formed outside the inside fuel region with coating fule particles of plutonium oxide in large quantity added thereto. Since the fuel region is thus formed in no uniformity, neutron absorption amount by plutonium 240 is reduced so that the amount of generated neutron in the entire reactor exceeds the absorption amount to enable use of plutonium fuel. (Kamimura, M.)

1980-01-01

212

Gas and temperature measurements on Xingjian coal field fires  

Science.gov (United States)

Up to know no robust methodology has been established that allows the estimation of coal loss - and the associated CO2 emissions - based on temperature and / or gas emission measurements. Such knowledge is a prerequisite for an aimed at accreditation for coal fire extinction measures within the clean development mechanism (CDM) context under the frame of the Kyoto protocol. During a field campaign in Xinjiang extended measurements on a specific coal fire site were performed to proof so far developed estimations for exhaust gas volumes. The investigations show that during the evaluation of gas emissions, based on preliminary data, an inconsistency between measured and calculated gas emissions for the fire area was observed. Therefore temperature measurements on a dense grid have been done as well, taking also faults and cracks into account, to analyse how these measurements correlate with the gas measurements. In addition, the temperature measurements that have been done serve as reference data sets for the analysis of thermal satellite images taken by the ASTER satellite sensor system. Ongoing research focuses on the development of robust routines to detect coal fires and to quantify the amount of the coal fire related radiative energy release (CFRE).

Schlömer, S.; Fischer, C.; Teschner, M.; Hirner, A.

2009-04-01

213

Reduction of NO{sub x} emission from oil-burner by exhaust-gas recirculation; Redukcja emisjii NO{sub x} przez recyrkulacje spalin w palniku olejowym  

Energy Technology Data Exchange (ETDEWEB)

Recirculation of exhaust-gas reduces NO{sub x} emission of oil-burners of about 40% without lowering the quality of combustion is presented. Flame extinction limits the range of recirculation to 25%. (author). 5 refs., 3 figs.

Borkowski, J.M. [Zaklad Projektowo-Wdrozeniowy Technik Cieplnych i Przeplywowych, Wroclaw (Poland); Kordylewski, W. [Politechnika Warszawska, Warsaw (Poland)

1995-05-01

214

Relationship between Vehicle Emissions Laws and Incidence of Suicide by Motor Vehicle Exhaust Gas in Australia, 2001–06: An Ecological Analysis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In an ecological study, David Studdert and colleagues show that areas of Australia with fewer vehicles pre-dating stringent carbon monoxide emission laws have lower rates of suicide due to asphyxiation by motor vehicle exhaust gas.

2010-01-01

215

MEGAS - multi-electrode gas sensor system. Micromechanical high-temperature sensor system on a Si basis for measurements of nitrogen monoxide concentrations in motor car exhaust. Final report; MEGAS - Multi-Elektroden-Gassensorsystem. Mikromechanisches Hochtemperatur-Sensorsystem aus Silizium-Basis zur Ermittlung von Stickstoffmonoxid-Konzentrationen im Kfz-Abgas. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

The IMSAS is working on an actively heated Si substrate with interdigital structures fo working temperatures up to 550 C and for aggressive working media. The following tasks were achieved: Gas sensor design; Process development and optimisation; Processing of the Si substrate; Optimisation of the sensor substrate. The following problems were encountered: Minimisation of intrinsic stress of the stratified packages; Optimisation of the adhesive strength; Development of a stable sensor heating up to 550 C; Development and optimisation of structuring methods; Combination of thin film and thick film technologies. Resistive gas sensors with titanium-tungsten mixed oxides must be heated to 500 C for fast and sensitive response to a NO atmosphere. The gas sensitivity is strongly temperature-dependent, i.e. gas sensor temperature contro is required. In the case of diesel engine catalytic converters, ambient temperatures are high and vary with the mode of operation and operating time. The sensor temperature must be at least as high as the maximum ambient temperature and must be kept stable at this level. (orig.) [German] Am IMSAS liegt der Schwerpunkt im Bereich der Entwicklung eines aktiv beheizten Siliziumsubstrates mit Interdigitalstrukturen, das Arbeitstemperaturen bis zu 550 C und aggressiven Umgebungsbedingungen standhaelt. Die Arbeitspakete lassen sich grob zusammenfassen: - Designerstellung des Gassensors - Prozessentwicklung und -optimierung - Prozessierung des Siliziumsubstrates - Optimierung des Sensorsubstrates. Aus diesen Schwerpunkten ergeben sich Schwierigkeiten, die im Projektverlauf geloest werden muessen: - Minimierung des intrinsischen Stresses der Schichtpakete - Optimierung der Haftfestigkeit der Schichten/Schichtpakete - Entwicklung einer stabilen Sensorheizung bis 550 C - Entwicklung und Optimierung der Strukturierungsmethoden - Kombination von Duenn- und Dickschichttechnik (Si-Technologie und Siebdruck). Resistive Gassensoren mit Titan-Wolfram-Mischoxiden muessen waehrend ihres Betriebs auf ca. 500 C geheizt werden, um schnell und empfindlich eine NO-Atmosphaere ansprechen zu koennen. Die Gassensitivitaet ist stark von der Temperatur abhaengig. Aus diesem Grunde muss die Temperatur des Gassensors geregelt werden. Im Anwendungsfall Dieselkatalysator sind erhoehte Umgebungstemperaturen vorhanden, diese variieren je nach Betriebsdauer und Lastfall. Die Sensortemperatur muss deshalb mindestens so hoch sein, wie die maximale Temperatur der Umgebung und dabei stabil gehalten werden. (orig.)

Junge, S.

2002-07-01

216

Effects of Vapor Pressure, Oxygen Content, and Temperature on CO Exhaust Emissions.  

Science.gov (United States)

The effects caused by changes in gasoline RVP and oxygen content on exhaust emissions have been of concern for quite some time and adjustments to account for these effects were incorporated into the U.S. EPA's MOBILE series of emission factor models durin...

D. McClement H. Haskew J. Heiken J. Lyons R. Crawford

2009-01-01

217

Noble gas impurity balance and exhaust model for DIII-D and JET  

International Nuclear Information System (INIS)

Experiments to study the exhaust of noble gases (helium, neon) with cryopumping in DIII-D Advanced Divertor Program (ADP) configuration and in JET (Mk1 configuration) found significant differences in the global exhaust rate of helium, while efficient neon exhaust was observed in both machines. An attempt to better understand the basic processes governing the exhaust of noble gases in ELMy H-mode with cryopumping has been undertaken. Since divertor geometries investigated in the DIII-D and in the JET cases have significant differences, a comparative modeling study has been undertaken using the MIST core impurity transport code and the b2.5 time-independent divertor transport code. Photodiode measurements are used to determine ELM frequency, and charge-exchange recombination (CER) measurements are compared with the MIST ELM model to evaluate transport coefficients in the core plasma. A significant reduction in the anomalous diffusivities is found for the non-ELM component of radial transport without the need for a pinch velocity, and the model provides a more coherent description than the conventional ELM-averaged approach. Sensitivity to boundary conditions has been studied through establishment of a database of divertor enrichment cases using b2.5

1998-05-18

218

Pollutants in exhaust gas and ways to reduce them in passenger car engines without using catalytic convertors  

Energy Technology Data Exchange (ETDEWEB)

The chances ot significantly reducing the pollutants in exhaust was without using a catalytic convertor are all other than hopeless. Most systems do entail additional costs or at least detract from the general trend that has persisted until now oriented towards primary exonomy of operation. The most relevant exhaust components NOsub(x) (rising with temperature), HC (ignition delay angle being the main indication factor) and CO (a lack of air) are investigated in this paper and effective measures described. One of the emission concepts proposed here entails increasing CO in order to reduce NOsub(x). Such a measure appears suitable for retrofitting passenger cars out of current production equipped for afterburning of CO. Retarded ignition timing reduces NOsub(x) and HC values further; further reductions in pollutant emissions can be reached by limiting torque and temperature. Reference is made to the better emissions obtainable in diesel engines (Concept III); the author calls for application of more 6- and 8-cylinder diesels for higher road speeds in addition to the current low ones. Thus, good solutions and partial solutions to Europe's exhaust emissions problems could be implemented even without catalytic convertors.

Lech, G.

1985-10-01

219

On Developing a Spectroscopic System for Fast Gas Temperature Measurements in Combustion Environments  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Fourier Transform Infra Red (FTIR) spectroscopy techniques are known to provide reliable results for gas temperature measurements and can be comparatively easily performed on an industrial scale such as a boiler on a power plant or an exhaust of a ship engine cylinder. However temporal resolution is not high enough to trace fast temperature variations which are of great importance for complete combustion diagnostics. To eliminate the above mentioned shortcoming, a new IR spectroscopic-imaging...

Evseev, Vadim; Clausen, Sønnik

2009-01-01

220

DEVELOPMENT AND TESTING OF AN AMMONIA REMOVAL UNIT FROM THE EXHAUST GAS OF A MANURE DRYING SYSTEM  

Directory of Open Access Journals (Sweden)

Full Text Available The storage and handling of animal wastes is one of the main sources of ammonia gas emissions. Ammonia gas has a distinct, unpleasant odor and can become detrimental to the health of humans and animals at high concentrations. Ammonia emissions are of particular concern in manure drying systems, where large losses of nitrogen, in the form of ammonia can cause air quality concerns. The aim of this study was to develop an ammonia removal system for a poultry manure drying system. The thin layer drying of poultry manure in 1-3 cm thick layers resulted in effective sterilization; with the removal of 99.44-99.56% of total bacterial count, 88.51-93.705 of yeast and mold cells, 99.13-99.565 of E.coli cells, and complete removal of Salmonellae. The drying of poultry manure resulted in a large loss of nitrogen, through ammonia loss in the exhaust gasses. The use of a water scrubber resulted in a 75-99% removal of ammonia gas from the exhaust gases. The absorption of ammonia into the scrubberâ??s water resulted in an increase in pH, which subsequently fell as the drying process finished, and ammonia emission decreased. The heated air drying of poultry manure, with the use of an ammonia removal system proved effective in reducing the odor intensity and offensiveness of the poultry manure drying process, resulting in increased air quality. While producing a high value product.

A. E. Ghaly

2013-01-01

 
 
 
 
221

Polymer spiral film gas-liquid heat exchanger for waste heat recovery in exhaust gases  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this master thesis report the development of an innovative spiral heat exchanger based on polymer materials is described. Building prototypes, erection of a test bench and firsts tests of the heat exchanger are presented. The heat exchanger prototype survived all tests especially several days in contact with aggressive gases. A facility integrating a Diesel exhaust gases production has been developed to test this heat exchanger design. Performance results obtained during the tes...

Breton, Antoine

2012-01-01

222

Dismantling of the exhaust gas chimney of the Rossendorf isotope production facility  

International Nuclear Information System (INIS)

Since 1958 in the Rossendorf research center isotope production has been performed. in 2000 the facility was shut-down. The exhaust air was released by a chimney with 50 m height. Following the complete dismantling of the isotope production facility the chimney is the last component to be dismantled. The authors describe the radiological and technical problems to be solved. Based on the measuring program the decontamination procedure and the dismantling procedures were planned and performed.

2009-01-01

223

Oxidation and exhaust gas corrosion resistance of the cobalt base clad layers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Purpose: Purpose of this work is describing the behaviour of the cobalt base cladding layers after treatment in hot air (750°C, 200 hours) and exhaust gases (700°C, two month).Design/methodology/approach: The layers were produced by two cladding, laser and PTA, cladding technique. Cladding was conducted with a high power diode laser HDPL ROFIN SINAR DL 020 and Plasma Transformed Arc method. The layers consisted of three multitracking sublayers. The cobalt base layers were evaluated by micro...

2008-01-01

224

Quantification of diesel exhaust gas phase organics by a thermal desorption proton transfer reaction mass spectrometer  

Science.gov (United States)

A new approach was developed to measure the total abundance of long chain alkanes (C12 and above) in urban air using thermal desorption with a proton transfer reaction mass spectrometer (PTR-MS). These species are emitted in diesel exhaust and may be important precursors to secondary organic aerosol production in urban areas. Long chain alkanes undergo dissociative proton transfer reactions forming a series of fragment ions with formula CnH2n+1. The yield of the fragment ions is a function of drift conditions. At a drift field strength of 80 Townsends, the most abundant ion fragments from C10 to C16 n-alkanes were m/z 57, 71 and 85. The PTR-MS is insensitive to n-alkanes less than C8 but displays an increasing sensitivity for larger alkanes. Higher drift field strengths yield greater normalized sensitivity implying that the proton affinity of the long chain n-alkanes is less than H2O. Analysis of diesel fuel shows the mass spectrum was dominated by alkanes (CnH2n+1), monocyclic aromatics, and an ion group with formula CnH2n-1 (m/z 97, 111, 125, 139). The PTR-MS was deployed in Sacramento, CA during the Carbonaceous Aerosols and Radiative Effects Study field experiment in June 2010. The ratio of the m/z 97 to 85 ion intensities in ambient air matched that found in diesel fuel. Total diesel exhaust alkane concentrations calculated from the measured abundance of m/z 85 ranged from the method detection limit of ~1 ?g m-3 to 100 ?g m-3 in several air pollution episodes. The total diesel exhaust alkane concentration determined by this method was on average a factor of 10 greater than the sum of alkylbenzenes associated with spark ignition vehicle exhaust.

Erickson, M. H.; Wallace, H. W.; Jobson, B. T.

2012-02-01

225

Quantification of diesel exhaust gas phase organics by a thermal desorption proton transfer reaction mass spectrometer  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A new approach was developed to measure the total abundance of long chain alkanes (C12 and above) in urban air using thermal desorption with a proton transfer reaction mass spectrometer (PTR-MS). These species are emitted in diesel exhaust and may be important precursors to secondary organic aerosol production in urban areas. Long chain alkanes undergo dissociative proton transfer reactions forming a series of fragment ions with formula Cn&...

2012-01-01

226

Heat recovery from dryer exhaust gas. Final report; Rueckgewinnung von Abwaerme aus Trocknerabgas. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

A pilot plant for heat recovery from dryer off-gas with the aid of an open sorption circuit was constructed. The heat was used for heating service water. Depending on the initial moisture (150-240 g/kg), 100-140 kW could be recovered from water as washing liquid at service water temperatures of 56-67 C. With a 29 Ma % calcium chloride solution, service water temperatures of 65-80 C were possible at a washing liquid concentration of 34 Ma%. Demoisturizing of the flue gas by up to 25% resulted in a thermal efficiency of upl to 33%. Higher thermal efficiencies are possible with open sorption cycles. The data of the model process reflect the process rather well. [German] Mit dem Ziel der Ueberpruefung und Ergaenzung der bisher gewonnenen Erkenntnisse wurde in Zusammenarbeit mit einem potentiellen Nutzer eine Versuchsanlage zur Waermerueckgewinnung aus Trocknerabgasen mit Hilfe eines offenen Sorptionskreislaufes errichtet. Die bei der Rauchgasauskuehlung und -entfeuchtung zurueckgewonnene Waerme diente zur Aufheizung eines Brauchwasserstromes. In Abhaengigkeit von der Eintrittsfeuchte (150-240 g/kg) konnten aus einem Rauchgasstrom von ca. 2700 m{sup 3}/h bei dem Einsatz von Wasser als Waschfluessigkeit eine Waerme von 100-140 kW bei Brauchwassertemperaturen von 56-67 C zurueckgewonnen werden. Der Einsatz einer 29 Ma%-igen Kalziumchloridloesung gestattete Brauchwassertemperaturen von 65-80 C bei einer Leistung von 90-118 kW. Temperaturen bis zu 86 C bei einer Leistung von 90 kW wurden bei einer Waschfluessigkeitskonzentration von ca. 34 Ma% erreicht. Durch die Entfeuchtung des Rauchgases um bis zu 25% konnte ein thermischer Wirkungsgrad von bis zu 33% erzielt werden. Hoehere thermische Wirkungsgrade sind durch die Anwendung offener Sorptionskreisprozesse erreichbar. Die mit Hilfe des Modellprozesses ermittelten Daten gaben das Prozessverhalten relativ gut wieder. (orig.)

Haehre, P.; Ostrovski, N.; Genssle, A.

2001-07-01

227

Influence of steam injection through exhaust heat recovery on the design performance of solid oxide fuel cell . gas turbine hybrid systems  

International Nuclear Information System (INIS)

This study analyzed the influence of steam injection on the performance of hybrid systems combining a solid oxide fuel cell and a gas turbine. Two different configurations (pressurized system and ambient pressure system) were examined and the effects of injecting steam, generated by recovering heat from the exhaust gas, on system performances were compared. Performance variations according to the design of different turbine inlet temperatures were examined. Two representative gas turbine pressure ratios were used. Without steam injection, the pressurized system generally exhibits higher system efficiency than the ambient pressure system. The steam injection augments gas turbine power, thus increasing the power capacity of the hybrid system. The power boost effect due to the steam injection is generally greater in the relatively higher pressure ratio design in both the pressurized and ambient pressure systems. The effect of the steam injection on system efficiency varies depending on system configurations and design conditions. The pressurized system hardly takes advantage of the steam injection in terms of system efficiency. On the other hand, the steam injection contributes to the efficiency improvement of the ambient pressure system in some design conditions. In particular, a higher pressure ratio provides a better chance of efficiency increase due to the steam injection

2009-02-01

228

Emission characteristics of iso-propanol/gasoline blends in a spark-ignition engine combined with exhaust gas re-circulation  

Directory of Open Access Journals (Sweden)

Full Text Available Experiments were carried out in a spark-ignition engine fueled with iso-propanol/gasoline blends. Emission characteristics of this engine were investigated experimentally, including gaseous emissions (HC, CO, NOx and particulate matter emission in term of number and size distributions. The effects of different iso-propanol percentages, loads and exhaust gas recirculation rates on emissions were analyzed. Results show that the introduction of exhaust gas recirculation reduces the NOx emission and NOx emission gives the highest value at full load condition. HC and CO emissions present inconspicuous variations at all the loads except the load of 10%. Additionally, HC emission shows a sharp increase for pure propanol when the exhaust gas recirculation rate is up to 5%, while little variation is observed at lager exhaust gas recirculation rates. Moreover, the particulate matter number concentration increases monotonically with the increase of load and the decrease of exhaust gas recirculation rate. There exists a critical spark timing that produces the highest particulate matter number concentration at all the blending ratios.

Gong Jing

2014-01-01

229

Design of thermoelectric generators operating on exhaust gas from marine diesel engines  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The design of thermoelectric generator (TEG), forming the exhaust system of the vessel, is offered in the paper. Thermal calculation of the TEG for the ves-sel engine, Ro-8 6VDS48/42-AL2, with the capacity of 2 650 kW is given. Values of output parameters of the TEG are comparable with output values of the pa-rameters of existing analogues. The thermoelectric generator with the received parameters can be used on a vessel as an additional source of the direct current electric power.

2010-01-01

230

Design of thermoelectric generators operating on exhaust gas from marine diesel engines  

Directory of Open Access Journals (Sweden)

Full Text Available The design of thermoelectric generator (TEG, forming the exhaust system of the vessel, is offered in the paper. Thermal calculation of the TEG for the ves-sel engine, Ro-8 6VDS48/42-AL2, with the capacity of 2 650 kW is given. Values of output parameters of the TEG are comparable with output values of the pa-rameters of existing analogues. The thermoelectric generator with the received parameters can be used on a vessel as an additional source of the direct current electric power.

Khalykov Kamil Rafaelevich

2010-04-01

231

Quantification of diesel exhaust gas phase organics by a thermal desorption proton transfer reaction mass spectrometer  

Directory of Open Access Journals (Sweden)

Full Text Available A new approach was developed to measure the total abundance of long chain alkanes (C12 and above in urban air using thermal desorption with a proton transfer reaction mass spectrometer (PTR-MS. These species are emitted in diesel exhaust and may be important precursors to secondary organic aerosol production in urban areas. Long chain alkanes undergo dissociative proton transfer reactions forming a series of fragment ions with formula CnH2n+1. The yield of the fragment ions is a function of drift conditions. At a drift field strength of 80 Townsends, the most abundant ion fragments from C10 to C16 n-alkanes were m/z 57, 71 and 85. The PTR-MS is insensitive to n-alkanes less than C8 but displays an increasing sensitivity for larger alkanes. Higher drift field strengths yield greater normalized sensitivity implying that the proton affinity of the long chain n-alkanes is less than H2O. Analysis of diesel fuel shows the mass spectrum was dominated by alkanes (CnH2n+1, monocyclic aromatics, and an ion group with formula CnH2n?1 (m/z 97, 111, 125, 139. The PTR-MS was deployed in Sacramento, CA during the Carbonaceous Aerosols and Radiative Effects Study field experiment in June 2010. The ratio of the m/z 97 to 85 ion intensities in ambient air matched that found in diesel fuel. Total diesel exhaust alkane concentrations calculated from the measured abundance of m/z 85 ranged from the method detection limit of ~1 ?g m?3 to 100 ?g m?3 in several air pollution episodes. The total diesel exhaust alkane concentration determined by this method was on average a factor of 10 greater than the sum of alkylbenzenes associated with spark ignition vehicle exhaust.

M. H. Erickson

2012-02-01

232

Meeting future exhaust emissions standards using natural gas as a vehicle fuel: Lessons learned from the natural gas vehicle challenge `92  

Energy Technology Data Exchange (ETDEWEB)

The Natural Gas Vehicle Challenge `92, organized by Argonne National Laboratory and sponsored by the US Department of Energy, the Energy, Mines, and Resources - Canada, the Society of Automotive Engineers, and many others, resulted in 20 varied approaches to the conversion of a gasoline-fueled, spark-ignited, internal combustion engine to dedicated natural gas use. Starting with a GMC Sierra 2500 pickup truck, donated by General Motors, teams of college and university student engineers strived to optimize Chevrolet V-8 engines operating on natural gas for improved emissions, fuel economy, performance, and advanced design features. This paper focuses on the results of the emission event, and compares engine mechanical configurations, engine management systems, catalyst configurations and locations, and approaches to fuel control and the relationship of these parameters to engine-out and tailpipe emissions of regulated exhaust constituents. Nine of the student-modified trucks passed the current levels of exhaust emission standards, and some exceeded the strictest future emissions standards envisioned by the US Environmental Protection Agency. Factors in achieving good emissions control using natural gas are summarized, and observations concerning necessary components of a successful emissions control strategy are presented.

Rimkus, W.A.; Larsen, R.P.

1992-09-01

233

Onboard Plasmatron Generation of Hydrogen rich Gas for Diesel Engine Exhaust Aftertreatment and Other Applications  

Energy Technology Data Exchange (ETDEWEB)

Plasmatron reformers can provide attractive means for conversion of diesel fuel into hydrogen rich gas. The hydrogen rich gas can be used for improved NOx trap technology and other aftertreatment applications.

Bromberg, L.; Cohn, D.R.; Heywood,J.; Rabinovich, A.

2002-08-25

234

METHANOL MEASUREMENT IN AUTO EXHAUST USING A GAS-FILTER CORRELATION SPECTROMETER  

Science.gov (United States)

Spectroscopic methods offer an alternative to wet chemical methods for analysis of methanol emissions from automobiles. The gas filter correlation infrared optical analysis approach appears very promising. The report describes the gas correlation optical system constructed to ana...

235

Increasing the Selectivity of Pt-Gate SiC Field Effect Gas Sensors by Dynamic Temperature Modulation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Based on a diode coupled silicon carbide field effect transistor (FET) with platinum as catalytic gate material, the influence of dynamic temperature modulation on the selectivity of gas analysis sensors FETs has been investigated. This operating mode, studied intensively for semiconductor gas sensors, has only recently been applied to FETs. A suitable temperature cycle for detection of typical exhaust gases (CO, NO, C3H6, H-2, NH3) was developed and combined with appropriate signal processin...

Bur, Christian; Reimann, Peter; Andersson, Mike; Schuetze, Andreas; Lloyd Spetz, Anita

2012-01-01

236

Computer simulation of hydrogen-diesel dual fuel exhaust gas emissions with experimental verification  

Energy Technology Data Exchange (ETDEWEB)

The drawback of lean operation with hydrocarbon fuels is a reduced power output. Lean operation of hydrocarbon engines has additional drawbacks. Lean mixtures are hard to ignite, despite the mixture being above the low fire (point) limit of the fuel. This results in misfire, which increases un-burned hydrocarbon emissions, reduces performance and wastes fuel. Hydrogen can be used in conjunction with compact liquid fuels such as gasoline; alcohol or diesel provided each is stored separately. Mixing hydrogen with other hydrocarbon fuels reduces all of these drawbacks. Hydrogen's low ignition energy limit and high burning speed makes the hydrogen/hydrocarbon mixture easier to ignite, reducing misfire and thereby improving emissions, performance and fuel economy. Regarding power output, hydrogen augments the mixture's energy density at lean mixtures by increasing the hydrogen-to-carbon ratio, and thereby improves torque at wide-open throttle conditions. This paper involves the simulation program for determining the mole fraction of each of the exhaust species when the hydrogen is burnt along with diesel and the results are presented. The proportion of hydrogen in the hydrogen-diesel blend affecting the mole fraction of the exhaust species is also simulated. Experimental investigations were carried out, in hydrogen-diesel dual fuel mode, which showed a good agreement between the predicted and experimental results. The program code developed is valid for any combination of dual fuels. 14 refs., 15 figs., 1t ab.

M. Masood; M.M. Ishrat [M.J. College of Engineering and Technology, Hyderabad (India). Mechanical Engineering Department

2008-06-15

237

Ejection of toxic and carcinogenic substances along with the exhaust gasses of gas turbine engines and ways of reducing them  

Energy Technology Data Exchange (ETDEWEB)

Studies of the amount of carcinogenic substances in exhaust gasses of piston aviation engines showed that the concentration of Benzene (A) tyrene in exhaust gasses is found at a level of 0.5-5 micrograms/m/sup 3/. It increases with an increase of a load, rotation frequency and angle of advance of fuel injection. The maximum concentration of Benzene(A)tyrene is observed in transitional states related to acceleration of the airplane. Measures to reduce the ejection of NO (injection of water into the combustion chamber, the use of water and fuel emulsions, recirculation of the treated gasses into the combustion chamber) relates to an increase of Benzene(a)tyrene ejections. Tests were carried out on an experimental test bed using the gas turbine aviation engine type AI-9 to determine the amount of waste gasses that are carcinogenic and toxic. The Benzene(a)tyrene concentration in waste gasses of piston engines (0.8 micrograms/m/sup 3/) with an increase of the total coefficient of excess air in a combustion chamber increases by a factor of 2 to 4. Enriching the fuel-air mixture with hydrogen in a combustion chamber of a gas turbine engine by adding hydrogen to the primary zone of the combustion chamber simultaneously reduces the concentration of waste gasses, Benzene(a)tyrene and CO. For the AI-25 gas turbine engine the addition of hydrogen in the amount of 5% mass of fuel reduces the ejection of CO by a factor of 2, and that of Benzene(a)tyrene by a factor of 7.

Varshavskiy, I.L.; Kanilo, P.M.; Khesina, A.Y.; Ryabeka, V.P.; Smirnov, G.A.

1981-01-01

238

Development of exhaust reburning technology for co-generation; Cogeneration yo haiki sainensho gijutsu no kaihatsu  

Energy Technology Data Exchange (ETDEWEB)

In this report, the energy-saving and economic features of the exhaust reburning system are described; the structures, combustion performance, and NOx performance of two types of burners are shown; and then the system design is outlined. In addition, a reference is made to an exhaust recombustion burner which adapts to the electrothermally variable chain cycle gas turbine and to the lean gas engine. In a co-generation system, the heat contained in the gas turbine exhaust is recovered in the waste heat boiler in the form of steam. It is the added combustion system and the exhaust recombustion system that increase the quantity of heat contained in the gas turbine exhaust for an increase in the amount of steam to be recovered. The gas turbine exhaust contains oxygen with its concentration level 13-15wet% and its temperature 500-600 degrees C, and the exhaust recombustion system utilizes only this exhaust as the combustion air. The exhaust recombustion burner is provided with two stages of swirlers installed near the gas nozzle for the augmentation of flame holding capability, and is assured of a stable combustion in the turbine exhaust until the post-combustion residual oxygen concentration level is as low as 3wet%. (NEDO)

Ogura, T.; Tanaka, Y. [Osaka Gas Co. Ltd., Osaka (Japan); Yamazaki, A. [Chugai Ro Co. Ltd., Osaka (Japan); Kobayashi, H.

1999-03-01

239

Activity enhancement of Ag/mordenite catalysts by addition of palladium for the removal of nitrogen oxides from diesel engine exhaust gas  

Energy Technology Data Exchange (ETDEWEB)

Various Ag-Pd/mordenite catalysts were prepared on washcoated honeycombs and tested in terms of NO{sub x} removal from diesel exhaust gas with (CH{sub 3}){sub 2}O as a reducing agent at a practical high level of space velocity. The activity was dependent upon the palladium loading. In terms of NO{sub x} removal, the order of catalytic activity was Ag(3)/Pd(0.01)/mordenite Ag(3)/Pd(0.1)/mordenite Ag(3)/mordenite catalyst Ag(3)/Pd(1.0)/mordenite. It was found that a relatively small loading of palladium on Ag/mordenite catalysts led to a significant improvement in catalytic activity over a wide range of temperatures. The properties of these catalysts were also investigated by the NH{sub 3} temperature programed desorption (TPD) and BET method. It was found that Ag(3)/Pd(0.01)/mordenite had a larger amount of acid sites. It was concluded that Ag/mordenite catalyst with a small amount of palladium can effectively remove NO{sub x} over a wide range of temperatures using (CH{sub 3}){sub 2}O as a reducing agent

Masuda, K.; Tsujimura, K. [New A.C.E. Institute Co., Ltd., Ibaraki (Japan); Shinoda, K.; Kato, T. [Mitsui Mining and Smelting Co., Ltd., Saitama (Japan)

1998-01-15

240

Low-temperature gas from marine shales: wet gas to dry gas over experimental time  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Marine shales exhibit unusual behavior at low temperatures under anoxic gas flow. They generate catalytic gas 300° below thermal cracking temperatures, discontinuously in aperiodic episodes, and lose these properties on exposure to trace amounts of oxygen. Here we report a surprising reversal in hydrocarbon generation. Heavy hydrocarbons are formed before light hydrocarbons resulting in wet gas at the onset of generation grading to dryer gas over time. The effect is moderate under gas flow a...

Mango, Frank D.; Jarvie, Daniel M.

2009-01-01

 
 
 
 
241

Device for the removal of sulfur dioxide from exhaust gas by pulsed energization of free electrons  

International Nuclear Information System (INIS)

The performance of a new device using pulsed streamer corona for the removal of sulfur dioxide from humid air has been evaluated. The pulsed streamer corona produced free electrons which enhance gas-phase chemical reactions, and convert SO2 to sulfuric acid mist. The SO2 removal efficiency was compared with that of the electron-beam flue-gas treatment process. The comparison demonstrates the advantage of the novel device

1984-10-04

242

40 CFR 86.1710-99 - Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and...  

Science.gov (United States)

...2010-07-01 2010-07-01 false Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and light light-duty trucks. 86.1710-99 Section 86.1710-99 Protection of Environment ENVIRONMENTAL...

2010-07-01

243

40 CFR 86.1710-99 - Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and...  

Science.gov (United States)

...2013-07-01 2013-07-01 false Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and light light-duty trucks. 86.1710-99 Section 86.1710-99 Protection of Environment ENVIRONMENTAL...

2013-07-01

244

Stability of exhaust gas split ratio during mode test for diesel particulate measurement. Bunryushiki kishaku tunnel wo mochiite diesel ryushi wo hyokasuru sai no bunryuhi no anteikaho  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the result of discussing the stability of exhaust gas split ratio under Diesel-13 (D13) mode operating condition as reported at the Central Council for Environmental Pollution Control, using a partial flow dilution tunnel. Variation in the exhaust gas split ratio due to emission vibration increases in a test mode with low flow rates, but it can be reduced by mounting a muffler used in an actual car onto the exhaust pipe. The variation in the split ratio during the D-13 mode test can be made within [plus minus] 5% by using a manual adjusting method that adjusts openings of a motor-driven valve at the dilution tunnel inlet so that the split ratios at operating the engine in the 7th mode (maximum exhaust flow rate) and the 1st mode (low exhaust flow rate) become equivalent to the set split ratios. The said motor-driven valve is adjusted in such a manner that a split ratio calculated from data obtained from a split ratio monitor coincides with the set split ratio having been inputted initially. Using an automatic adjusting device can also achieve the same result as the above description. 8 refs., 5 figs., 1 tab.

Ryu, H.; Hiranuma, K.; Suzuki, T. (Japan Automobile Research Institute, Inc., Tsukuba (Japan))

1992-11-01

245

Equilibrium molecular dynamics and mean first passage time analysis of the separation of exhaust gases at high temperatures by silica nanoporous membranes  

International Nuclear Information System (INIS)

An investigation of mechanisms associated with the high selectivity of a gas mixture at high temperatures by silica nanoporous membranes has been conducted in the framework of equilibrium classical molecular dynamic simulations and formalism of fractional diffusion equation on a sample of a gas mixture of exhaust gases. The important feature is the quite realistic modeling of the silica nanoporous membranes based on the use of an analytic bond order potential and the conception of dangling bonds. The last two were successfully employed to model the realistic silica chemical vapor deposition process (Burlakov et al 2001 Phys. Rev. Lett. 86 3052). The dependence of the selective properties on temperature, density (voidage volume) and morphology has been investigated. The selectivity at a low temperature (673?K) is found to be more efficient than at a high temperature (873?K). When only Lennard-Jones interaction between a gas and a solid is included the selectivity is found to be changed at the low temperature (673?K) from 1.2?:?1 for a density of 50% to 1.03?:?1 for a density of 80%. Including an additional electrostatic interaction increases the selectivity from 1.79?:?1 for a density of 50% to 2.26?:?1 for a density of 80%. At the high temperature (873?K) when only Lennard-Jones potential is included the selectivity is found to be changed from 1.21?:?1 for a density of 50% to 1.13?:?1 for a density of 80%. With an additional electrostatic force the selectivity is found to be the same for all densities at around 1.43?:?1. The conclusion is that the most efficient conditions for the selective membrane are a temperature of 673?K and a high density. Under these conditions the mean first passage times for species O2 and N2 are almost the same and much less than for species CO2. The methodology developed is general. This paper is based on the author's PhD thesis

2010-03-01

246

Exhaust back pressure reducer  

Energy Technology Data Exchange (ETDEWEB)

This patent describes an exhaust back pressure reducer for the internal combustion engine of a tractor for pulling a trailer. The tractor has a cab. An air deflector on the top of the cab deflect air over the top of the trailer as the tractor pulls the trailer over the road, and it includes exhaust system for the engine. The reducer comprises: means at the top of the air deflector on the top of the cab for aspirating gas from the engine exhaust system to reduce the exhaust back pressure on the engine. The aspirating means is positioned for flow therepast of air relative to the air deflector as the tractor travels forward. The aspirating means is ported for suctioning gas therefrom by the air flowing therepast.

Eller, H.E.

1987-05-19

247

Gas conduction in a high temperature reactor  

International Nuclear Information System (INIS)

The hot gas is distributed and mixed by polygonal blocks in the reactor floor. Radial and an annular channel are used for this purpose. This annular channel also carried circular ducts distributed evenly over the circumference, which lead to a heat exchanger. Temperature differences across the crossection of the reactor floor are evened out by multiple deflection, combination and renewed splitting of the gas flows. (DG)

1978-09-04

248

Intensity of corrosion processes in exhaust gas boilers at burning water-fuel emulsion  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Approximation dependences of specific rates of low-temperature sulfur corrosion and pollution intensity under the influence of the main parameters characterizing these processes are presented. Statistical processing of the research results that displayed the primary influence on decrease in metal sulfur and water content of water fuel emulsion is conducted. The dependences of low-temperature sulfur corrosion rate on the wall temperature for 100 and 1000 hours at burning standard fuel and wate...

2013-01-01

249

Near-explicit Gas-phase Chemistry Coupled with Extensive Aqueous Mechanism: Looking at Ethanol (E85) Exhaust in a Fog  

Science.gov (United States)

We combine a near-explicit gas-phase chemical mechanism with an extensive aqueous mechanism in a chemical solver to examine the effects of ethanol (E85) versus gasoline on the fate of pollutants in the presence of a fog. We use the Master Chemical Mechanism (MCM, version 3.1, Leeds University) and the Chemical Aqueous Phase Radical Mechanism, CAPRAM 3.0, with the SMVGEAR II chemical ordinary differential solver to provide the speed necessary to simulate complex chemistry. The MCM has over 13, 500 organic reactions and 4,600 species, while CAPRAM treats aqueous chemistry among 390 species and 829 reactions (including 51 gas-to-aqueous phase reactions). We validate a simplified version of the model against results from a comprehensive intercomparison by Barth et al (2003). In previous work on ethanol (E85), we analyzed the temperature-dependence of ethanol and gasoline exhaust chemistry and its impact on urban air pollution considering only gas-phase chemistry. In addition to the air pollution findings, we verified that using the MCM with SMVGEAR is practical in a 3-D model. Here, we extend our study to include aqueous chemistry in the presence of a fog. We investigate the impact aqueous reactions have on unburned ethanol and acetaldehyde mixing ratios in the atmosphere in particular because acetaldehyde is an ozone precursor and carcinogen, and aqueous oxidation has potential to speed the conversion of unburned ethanol to acetaldehyde. Acetaldehyde also forms acetic acid in aqueous solution. Acetic acid vapor is an eye, nose, and lung irritant, so both species contribute negatively to human health. We look at the impact of fog liquid water content and temperature on the degradation of emitted aromatic and other species as well, from both gasoline and E85.

Ginnebaugh, D. L.; Jacobson, M. Z.

2011-12-01

250

High temperature desulfurization of synthesis gas  

Energy Technology Data Exchange (ETDEWEB)

The hot process gas stream from the partial oxidation of sulfur-containing heavy liquid hydrocarbonaceous fuel and/or sulfur-containing solid carbonaceous fuel comprising gaseous mixtures of H.sub.2 +CO, sulfur-containing gases, entrained particulate carbon, and molten slag is passed through the unobstructed central passage of a radiant cooler where the temperature is reduced to a temperature in the range of about 1800.degree. F. to 1200.degree. F. From about 0 to 95 wt. % of the molten slag and/or entrained material may be removed from the hot process gas stream prior to the radiant cooler with substantially no reduction in temperature of the process gas stream. In the radiant cooler, after substantially all of the molten slag has solidified, the sulfur-containing gases are contacted with a calcium-containing material to produce calcium sulfide. A partially cooled stream of synthesis gas, reducing gas, or fuel gas containing entrained calcium sulfide particulate matter, particulate carbon, and solidified slag leaves the radiant cooler containing a greatly reduced amount of sulfur-containing gases.

Najjar, Mitri S. (Hopewell Junction, NY); Robin, Allen M. (Anaheim, CA)

1989-01-01

251

Mutagenicity of diesel engine exhaust is eliminated in the gas phase by an oxidation catalyst but only slightly reduced in the particle phase.  

Science.gov (United States)

Concerns about adverse health effects of diesel engine emissions prompted strong efforts to minimize this hazard, including exhaust treatment by diesel oxidation catalysts (DOC). The effectiveness of such measures is usually assessed by the analysis of the legally regulated exhaust components. In recent years additional analytical and toxicological tests were included in the test panel with the aim to fill possible analytical gaps, for example, mutagenic potency of polycyclic aromatic hydrocarbons (PAH) and their nitrated derivatives (nPAH). This investigation focuses on the effect of a DOC on health hazards from combustion of four different fuels: rapeseed methyl ester (RME), common mineral diesel fuel (DF), SHELL V-Power Diesel (V-Power), and ARAL Ultimate Diesel containing 5% RME (B5ULT). We applied the European Stationary Cycle (ESC) to a 6.4 L turbo-charged heavy load engine fulfilling the EURO III standard. The engine was operated with and without DOC. Besides regulated emissions we measured particle size and number distributions, determined the soluble and solid fractions of the particles and characterized the bacterial mutagenicity in the gas phase and the particles of the exhaust. The effectiveness of the DOC differed strongly in regard to the different exhaust constituents: Total hydrocarbons were reduced up to 90% and carbon monoxide up to 98%, whereas nitrogen oxides (NO(X)) remained almost unaffected. Total particle mass (TPM) was reduced by 50% with DOC in common petrol diesel fuel and by 30% in the other fuels. This effect was mainly due to a reduction of the soluble organic particle fraction. The DOC caused an increase of the water-soluble fraction in the exhaust of RME, V-Power, and B5ULT, as well as a pronounced increase of nitrate in all exhausts. A high proportion of ultrafine particles (10-30 nm) in RME exhaust could be ascribed to vaporizable particles. Mutagenicity of the exhaust was low compared to previous investigations. The DOC reduced mutagenic effects most effectively in the gas phase. Mutagenicity of particle extracts was less efficiently diminished. No significant differences of mutagenic effects were observed among the tested fuels. In conclusion, the benefits of the DOC concern regulated emissions except NO(X) as well as nonregulated emissions such as the mutagenicity of the exhaust. The reduction of mutagenicity was particularly observed in the condensates of the gas phase. This is probably due to better accessibility of gaseous mutagenic compounds during the passage of the DOC in contrast to the particle-bound mutagens. Concerning the particulate emissions DOC especially decreased ultrafine particles. PMID:22587467

Westphal, Götz A; Krahl, Jürgen; Munack, Axel; Ruschel, Yvonne; Schröder, Olaf; Hallier, Ernst; Brüning, Thomas; Bünger, Jürgen

2012-06-01

252

Modelling diesel engines with a variable-geometry turbocharger and exhaust gas recirculation by optimization of model parameters for capturing non-linear system dynamics  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A mean-value model of a diesel engine with a variable-geometry turbocharger (VGT) and exhaust gas recirculation (EGR) is developed, parameterized, and validated. The intended model applications are system analysis, simulation, and development of model-based control systems. The goal is to construct a model that describes the gas flow dynamics including the dynamics in the manifold pressures, turbocharger, EGR, and actuators with few states in order to obtain short simulation times. An investi...

Wahlstro?m, Johan; Eriksson, Lars

2011-01-01

253

METHANE EMISSIONS FROM THE NATURAL GAS INDUSTRY VOLUME 11: COMPRESSOR DRIVER EXHAUST  

Science.gov (United States)

The 15-volume report summarizes the results of a comprehensive program to quantify methane (CH4) emissions from the U.S. natural gas industry for the base year. The objective was to determine CH4 emissions from the wellhead and ending downstream at the customer's meter. The accur...

254

Use of tracer gas techniques for industrial exhaust hood efficiency evaluation - application of sulfur hexafluoride for hood controlling particulate emissions  

Energy Technology Data Exchange (ETDEWEB)

One of the most commonly used controls of harmful industrial contaminants is a local exhaust hood. The efficiency of this system is defined as the ratio of air contaminant quantity captured by the system per unit time to the total contaminant quantity produced by the process per unit time. A tracer gas technique, using sulfur hexafluoride (SF/sub 6/), has been developed for the efficiency estimation of hoods controlling gaseous or vaporous contaminants. To extend the applicability of this method to hoods controlling particulate contaminants, a relationship between the hood particle capture efficiency and the hood efficiency determined by the tracer gas technique was studied. A particulate tracer was used for the hood efficiency and the data were compared with those obtained by the SF/sub 6/ technique. Both tracers were discharged under the same conditions. Based on a statistical data analysis, described in detail in this paper, a mathematical relationship between the efficiency obtained by both particulate and SF/sub 6/ was obtained for different velocity ratios (discharge velocity to capture velocity). For a hood controlling particles of 3 ..mu..m in diameter, no correction of the hood efficiency data estimated by the SF/sub 6/ technique is required. For larger particles, a corrective factor should be used for modification of the efficiency results obtained by the SF/sub 6/ technique.

Hampl, V.; Shulman, S.

1985-07-01

255

Fuel-air mixing apparatus for reducing gas turbine combustor exhaust emissions  

Science.gov (United States)

A fuel-air mixer for use in a combustion chamber of a gas turbine engine is provided. The fuel air mixing apparatus comprises an annular fuel injector having a plurality of discrete plain jet orifices, a first swirler wherein the first swirler is located upstream from the fuel injector and a second swirler wherein the second swirler is located downstream from the fuel injector. The plurality of discrete plain jet orifices are situated between the highly swirling airstreams generated by the two radial swirlers. The distributed injection of the fuel between two highly swirling airstreams results in rapid and effective mixing to the desired fuel-air ratio and prevents the formation of local hot spots in the combustor primary zone. A combustor and a gas turbine engine comprising the fuel-air mixer of the present invention are also provided as well as a method using the fuel-air mixer of the present invention.

Zupanc, Frank J. (Inventor); Yankowich, Paul R. (Inventor)

2006-01-01

256

Removal of CO{sub 2} from exhaust gas; CO{sub 2}-fjerning fra eksosgass  

Energy Technology Data Exchange (ETDEWEB)

Presentation. Statoil aims to reduce CO{sub 2} emission from Statoil operated facilities by 30% over the coming decade. This presentation discusses their strategies for doing it. The Kaarstoe CO{sub 2} separation and disposal concept is described. A joint pilot testing at Kaarstoe aims to demonstrate improvements in the traditional amine scrubbing process by use of gas/liquid membranes. Statoil has documented that separation and disposal of 1.2 mill ton CO{sub 2} per year from power stations and factories at Kaarstoe are technologically feasible. This corresponds approximately to all CO{sub 2} from a gas power station, and from new gas turbines installed at Statoil's plant. The separated CO{sub 2} is supposed to be transported through a pipe to Sleipner and disposed of in the Utsira formation. The costs of the plant including pipe and disposal system have been calculated to NOK 4900 mill. Identified technological improvements may reduce the investment to NOK 3800 mill. Technically a plant may be built within 2003.

Barland, Knut [Statoil, Stavanger (Norway)

1998-07-01

257

Low-temperature gas from marine shales: wet gas to dry gas over experimental time  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Marine shales exhibit unusual behavior at low temperatures under anoxic gas flow. They generate catalytic gas 300° below thermal cracking temperatures, discontinuously in aperiodic episodes, and lose these properties on exposure to trace amounts of oxygen. Here we report a surprising reversal in hydrocarbon generation. Heavy hydrocarbons are formed before light hydrocarbons resulting in wet gas at the onset of generation grading to dryer gas over time. The effect is modera...

Mango Frank D; Jarvie Daniel M

2009-01-01

258

Recommended launch-hold criteria for protecting public health from hydrogen chloride (HC1) gas produced by rocket exhaust  

Energy Technology Data Exchange (ETDEWEB)

Solid-fuel rocket motors used by the United States Air Force (USAF) to launch missiles and spacecraft can produce ambient-air concentrations of hydrogen chloride (HCI) gas. The HCI gas is a reaction product exhausted from the rocket motor during normal launch or emitted as a result of a catastrophic abort destroying the launch vehicle. Depending on the concentration in ambient air, the HCI gas can be irritating or toxic to humans. The diagnostic and complex-terrain wind field and particle dispersion model used by the Lawrence Livermore National Laboratory`s (LLNL`s) Atmospheric Release Advisory Capability (ARAC) Program was applied to the launch of a Peacekeeper missile from Vandenberg Air Force Base (VAFB) in California. Results from this deterministic model revealed that under specific meteorological conditions, cloud passage from normal-launch and catastropic-abort situations can yield measureable ground-level air concentrations of HCI where the general public is located. To protect public health in the event of such cloud passage, scientifically defensible, emergency ambient-air concentration limits for HCI were developed and recommended to the USAF for use as launch-hold criteria. Such launch-hold criteria are used to postpone a launch unless the forecasted meteorological conditions favor the prediction of safe ground-level concentrations of HCl for the general public. The recommended concentration limits are a 2 ppM 1-h time-weighted average (TWA) concentration constrained by a 1-min 10-ppM average concentration. This recommended criteria is supported by human dose-response information, including data for sensitive humans (e.g., asthmatics), and the dose response exhibited experimentally by animal models with respiratory physiology or responses considered similar to humans.

Daniels, J.I.; Baskett, R.L.

1995-11-01

259

On the possibility of exhaust gas recirculation in engine with combined mixture formation  

Directory of Open Access Journals (Sweden)

Full Text Available To the number of the considered questions there can be referred: formation of nitrogen oxides at temperature increase; the relationship of specific fuel consumption and temperature cycle indices; effect of compression ratio on engine parts; regulation of the angle of the beginning of the fuel supply and valve control mechanism. The comparison of the combined cycle with the cycle of Diesel is made. The positive features of the cycle operation approximate to isobaric, and the possibilities of obtaining the optimum ratio of specific fuel consumption and emissions of NOx are stated.

Andrusenko Oleg Evgenievich

2012-04-01

260

Temperature Anisotropy in a Driven Granular Gas  

CERN Multimedia

When smooth granular material is fluidized by vertically shaking a container, we find that the temperature in the direction of energy input always exceeds the temperature in the other directions. An analytical model is presented which shows how the anisotropy can be traced back to the inelasticity of the interparticle collisions and the collisions with the wall. The model compares very well with molecular dynamics simulations. It is concluded that any non-isotropic driving of a granular gas in a steady state necessarily causes anisotropy of the granular temperature.

Van der Meer, D; Meer, Devaraj van der; Reimann, Peter

2004-01-01

 
 
 
 
261

Exhaust pressure pulsation observation from turbocharger instantaneous speed measurement  

Science.gov (United States)

In internal combustion engines, instantaneous exhaust pressure measurements are difficult to perform in a production environment. The high temperature of the exhaust manifold and its pulsating character make its application to exhaust gas recirculation control algorithms impossible. In this paper an alternative method for estimating the exhaust pressure pulsation is presented. A numerical model is built which enables the exhaust pressure pulses to be predicted from instantaneous turbocharger speed measurements. Although the model is data based, a theoretical description of the process is also provided. This combined approach makes it possible to export the model for different engine operating points. Also, compressor contribution in the turbocharger speed pulsation is discussed extensively. The compressor contribution is initially neglected, and effects of this simplified approach are analysed.

Macián, V.; Luján, J. M.; Bermúdez, V.; Guardiola, C.

2004-06-01

262

Purex canyon exhaust fan bearing temperature monitoring system doric 245 datalogger programming  

International Nuclear Information System (INIS)

A micro-processor based datalogger is used to monitor, display, and log seventeen RTD temperature channels. Five bearings are monitored for each of the three electric motor-fan assemblies and two bearings are monitored on the steam turbine unit. Several alarms per data channel (a High alarm at 236 degrees and a High High alarm at 246 degrees F) will alert the operation's staff to increasing abnormal bearing temperatures. This procedure is cross-referenced to the manufacturers manual. All programming steps will have the following footnote: Mpg x-xx. The Mpg refers to the Manual page, with x as the section number and xx as the page number in that section. When more information is needed, such as pictures or details, then the manual section and page number is provided

1994-01-01

263

Purex canyon exhaust fan bearing temperature monitoring system doric 245 datalogger programming  

Energy Technology Data Exchange (ETDEWEB)

A micro-processor based datalogger is used to monitor, display, and log seventeen RTD temperature channels. Five bearings are monitored for each of the three electric motor-fan assemblies and two bearings are monitored on the steam turbine unit. Several alarms per data channel (a High alarm at 236 degrees and a High High alarm at 246 degrees F) will alert the operation`s staff to increasing abnormal bearing temperatures. This procedure is cross-referenced to the manufacturers manual. All programming steps will have the following footnote: Mpg x-xx. The Mpg refers to the Manual page, with x as the section number and xx as the page number in that section. When more information is needed, such as pictures or details, then the manual section and page number is provided.

Blackaby, W.B.

1994-09-06

264

Low temperature heat source for power generation: Exhaustive analysis of a carbon dioxide transcritical power cycle  

International Nuclear Information System (INIS)

The main results of a theoretical work on the use of a low temperature heat source for power generation through a carbon dioxide transcritical power cycle are reported in this paper. The procedure for analyzing the behaviour of the proposed cycle consisted in modifying the input pressure to the turbine from 66 bar, maintained constant each evaluated temperature (60 oC, 90 oC, 120 oC and 150 oC) until the net work was approximately zero. As a result, the maximum exergy efficiency was 50%, while the energy efficiencies obtained were 9.8%, 7.3%, 4.9% and 2.4% and the net specific work was 18.2 kJ/kg, 12.8 kJ/kg, 7.8 kJ/kg and 3.5 kJ/kg, respectively. Furthermore, the effect of the addition of an internal heat exchanger, which obviously supposed an increase in the efficiency, was analyzed. The analysis of the proposed system shows the viability of implementing this type of process as an energy alternative and/or strengthener of non-conventional energy sources in non-provided zones, or for increasing the energy efficiency in the industry. -- Highlights: ? Energy and exergy analysis of a carbon dioxide transcritical power cycle is reported. ? The effect of the inlet temperature to the turbine is evaluated. ? Conditions of maximum efficiency and maximum net work are compared. ? The inclusion of an IHX is also analysed.

2011-09-01

265

Effect on cold starting performance of an exhaust gas to engine coolant heat exchanger in an automobile  

Energy Technology Data Exchange (ETDEWEB)

The effect of exhaust-to-coolant heat exchange on fuel economy and cab heater performance during cold start was studied using a 1981 Ford Granada automobile and a 1977 Buick V-6 engine on a test stand. The ambient soaking temperatures ranged from 35 to -15 degrees Fahrenheit. It was found that fuel used in a 7 minute warm up run of the test stand engine was less by 2.1 to 4.6% when the heat exchanger replaced the muffler in the system. Likewise for the Granada, fuel consumption was less by 2.8 to 3.8% over an in town test route and less by 1.5 to 1.8% on a highway test route, when the heat exchanger replaced the muffler. Similarly, the time required for the coolant at the inlet of the cab heater to reach a temperature of 180 Fahrenheit was 27.5 to 28.8% shorter for the test stand engine, 6.3 to 7.0% shorter for the Granada in town route and 16.6 to 16.9% shorter for the Granada highway route, when the heat exchanger replaced the muffler.

Goettler, H.J.; Vidger, L.J.

1983-05-01

266

Tokamak fusion reactor exhaust  

International Nuclear Information System (INIS)

This report presents a compilation of papers dealing with reactor exhaust which were produced as part of the TIGER Tokamak Installation for Generating Electricity study at Culham. The papers are entitled: (1) Exhaust impurity control and refuelling. (2) Consideration of the physical problems of a self-consistent exhaust and divertor system for a long burn Tokamak. (3) Possible bundle divertors for INTOR and TIGER. (4) Consideration of various magnetic divertor configurations for INTOR and TIGER. (5) A appraisal of divertor experiments. (6) Hybrid divertors on INTOR. (7) Refuelling and the scrape-off layer of INTOR. (8) Simple modelling of the scrape-off layer. (9) Power flow in the scrape-off layer. (10) A model of particle transport within the scrape-off plasma and divertor. (11) Controlled recirculation of exhaust gas from the divertor into the scrape-off plasma. (U.K.)

1981-01-01

267

Cleaning of hot calciner exhaust gas by low-density ceramic filters  

Energy Technology Data Exchange (ETDEWEB)

Efficient dust removal at high temperatures gains increasing interest and ceramic filters are suitable to achieve high collection efficiencies for (sub-)micron particles. The paper presents experimental results for their application in lime-kiln operations. Experimental results were transformed into design equations for (i) the baseline pressure drop and the effect of the cleaning cycles; (ii) the total pressure drop and the effect of the dust load; (iii) the prediction of the time between two cleaning cycles in function of the operating parameters. (orig.)

Smolders, K.; Baeyens, J. [Katholieke Univ. Leuven, Heverlee (Belgium). Chemical Engineering Dept.

2000-09-11

268

Study on Thermal Conductivity Gas Sensor Constant Temperature Detection Method  

Directory of Open Access Journals (Sweden)

Full Text Available The thermal conductivity gas sensor can detect gas concentration that measure the thermal conductivity coefficient of the measured gas different from the background gas.This paper analyzes the theory of thermal conductivity gas sensor and method of measurement,proposes thermal conductivity gas sensor constant temperature detection method,and experimentally validate the feasibility of ambient temperature compensation. Experimental results show that the method effectively reduces the effect of ambient temperature on measuring accuracy.

Xi-bo Ding

2013-11-01

269

Exhaust gas aftertreatment for lean spark-plug engines; Abgasnachbehandlungskonzepte fuer mager betriebene Ottomotoren  

Energy Technology Data Exchange (ETDEWEB)

Out of all nitric-oxide reduction technologies described above the nictric-oxide storage/reduction method shows the highest efficiencies. In order to make the technology suitable for serial production it is necessary to increase temperature stability and sulfur tolerance. Passive SCR-catalytic converters have a higher sulfur tolerance but convert much less nitric oxides. Here again, temperature stability needs to be increased. There are not enough test results to make reliable statements as to the potential of selective catalytic reduction by means of added urea and reduction of nitric oxides in plasmas. To create a catalytic converter that can break down NO into its component parts under real-life conditions in a running spark-plug engine will require a stroke of genius indeed. (orig). [German] Von den beschriebenen Technologien zur Verringerung der NO{sub x}-Emissionen von Otto-Magermotoren bietet das NO{sub x}-Speicher/Reduktionsverfahren die hoechsten Wirkungsgrade. Die notwendigen Verbesserungen fuer eine praxisgerechte Serienanwendung dieser Technologie liegen in der Erhoehung der Temperaturstabilitaet und einer Verbesserung der Schwefeltoleranz. Demgegenueber sind passive SCR-Katalysatoren zwar schwefeltoleranter, haben aber eine deutlich geringere NO{sub x}-Konvertierung. Auch bei diesen Katalysatoren ist eine Verbesserung der Temperaturstabilitaet notwendig. Fuer eine zuverlaessige Einschaetzung des Potentials der selektiven katalytischen Reduktion mittels Harnstoff-Eindosierung und der NO{sub x}-Reduktion in Plasmen liegen nicht genuegend Testergebnisse aus praxisnahen ottomotorischen Anwendungen vor. Die Einfuehrung eines Katalysators, der in der Lage ist, NO unter den praktischen Betriebsbedingungen eines Otto-Magermotors direkt in seine Bestandteile zerfallen zu lassen, bedarf einer bahnbrechenden Erfindung. (orig.)

Dahle, U.; Brandt, S.; Velji, A. [Engelhard Technologies GmbH und Co OHG (Germany)

1998-07-01

270

Exhaust recirculation system for an internal combustion engine  

Energy Technology Data Exchange (ETDEWEB)

There is a transport device in the exhaust recirculation duct connecting the exhaust gas duct with the intake duct of an internal combustion engine, in order to return part of the exhaust gas positively from the exhaust gas duct to the intake duct. The fan has an electrically or mechanically driven fan wheel.

Ushimura, S.

1980-11-27

271

The Evolution of High Temperature Gas Sensors.  

Energy Technology Data Exchange (ETDEWEB)

Gas sensor technology based on high temperature solid electrolytes is maturing rapidly. Recent advances in metal oxide catalysis and thin film materials science has enabled the design of new electrochemical sensors. We have demonstrated prototype amperometric oxygen sensors, nernstian potentiometric oxygen sensors that operate in high sulfur environments, and hydrocarbon and carbon monoxide sensing mixed potentials sensors. Many of these devices exhibit part per million sensitivities, response times on the order of seconds and excellent long-term stability.

Garzon, F. H. (Fernando H.); Brosha, E. L. (Eric L.); Mukundan, R. (Rangachary)

2001-01-01

272

Additives for rapeseed oil fuel. Influence on the exhaust gas emissions  

Energy Technology Data Exchange (ETDEWEB)

In contrast to fossil diesel fuel, the use of additives is not common in rapeseed oil fuel. In a preceding research project the efficacy of several additives, that are commercially available for the use in fossil diesel or FAME, has been investigated for rapeseed oil fuel in the lab. Four additives could be identified, which have a significant influence on the ignition delay or the low temperature flow behaviour of rapeseed oil fuel. To investigate whether there are negative effects of the additives on other fuel-related properties in practical use, a test series on an agricultural tractor capable of running on vegetable oils has been conducted. Attention is focused on the operating parameters like power, torque or fuel consumption as well as on regulated emissions (CO, HC, particulate matter or NOx) and non-regulated emissions like polycyclic aromatic hydrocarbons. Additionally, the influence of the additives on the storage stability of rapeseed oil fuel is investigated in long term studies. No negative influence of the additives on the regulated emissions could be seen in the experiments, the data of the non-regulated emissions is still being analysed. This paper will focus on the emissions testing; results of the long term studies will be given in the presentation. (orig.)

Kastl, Johannes; Remmele, Edgar; Thuneke, Klaus [Technologie- und Foerderzentrum, Straubing (Germany)

2013-06-01

273

Fat from the food industry as regenerative fuels. Chemical treatment, fuel production, exhaust gas analysis; Fette aus der Lebensmittelindustrie als regenerative Kraftstoffe. Aufbereitung, Kraftstoffherstellung, Abgasanalytik  

Energy Technology Data Exchange (ETDEWEB)

The author investigates the possibility to purify and transesterify edible and animal fat to produce a fuel for combustion engines. This fuel is used for combined heat and power plants. Exhaust gas analysis during the combustion process of this fuel showed emission of dioxin and furan from selected charges of fuel, systematically contaminated with polychlorinated biphenyls (PCB). No toxic contamination was found. Transesterification was performed in a pilot plant; the transesterification of edible fat is similar to that of the common industrial transesterification of rape oil. The transesterification of animal fat is more laborious due to the higher concentration of free fatty acids. The results of the exhaust gas measurements show that compared to diesel fuel no principle disadvantage was found when fatty acid methyl ester of edible or animal fat is used as fuel. The use of fat with high contamination of PCB as raw material for the fatty acid methyl ester production did not show dangerous emissions of dioxins or furans.

Rauber, F.M.

2007-07-01

274

Abatement of dioxin emissions in electric arc furnace exhaust flue gas  

Energy Technology Data Exchange (ETDEWEB)

Steel is more and more produced in electric arc furnaces (EAFs) using scrap as a raw material comaterials associated with scrap (mineral ones such as copper and tin, organic ones such as paint, plastics, rubber, oil...) lead to undesirable gaseous emissions, such as PCDD/F (Polychlorinated Dioxins and Furans). The French Environmental Regulatory Administration publishes monitored value of PCDD/Fs emissions from MWI and Industry. The French Steel Industry is thus credited with 150 g TEQ/year, a figure down from 500 g given in earlier publications, from estimations obtained without experimental data. The EAFs themselves emit 36 g TEQ/year, with individual fluxes ranging from 0.1 to 13 ng-TEQ/Nm''3. As regulations on dioxin emissions at the stack are tightened, careful monitoring and development of effective, low-cost and more flexible countermeasures are essential. At EAF stack, Volatile Organic Compounds (VOCs) emissions are directly related to organics input, so that it is essential to use clean scrap and keep scrap clean on a sustainable basis. Nevertheless, concerning PCDD/F emissions, the correlation between input and output is not so clear-cut as far as trace elements are concerned, because formation from inorganic elements are possible and because condensation and adsorption can cut off emission peaks under very specific conditions. Two strategies have been evaluated to tackle the problem of controlling PCDD/F emissions. The first one consists of trapping PCDD/F by condensation. The second one is to practice optimized post-combustion in terms of abatement efficiency, operating residence time and temperature. (Author) 7 refs.

Arion, A.; Birat, J. P.; Marquaire, P. M.; Baronnet, F.

2002-07-01

275

Valve stem seals and cylinder head gaskets for minimal exhaust gas emissions and oil consumption; Ventilschaft- und Zylinderkopfdichtungen fuer minimale Abgasemissionen und Oelverbrauch  

Energy Technology Data Exchange (ETDEWEB)

It is a well known fact that ash from engine oil additives causes modern particulate filters in diesel cars to become clogged. Since the particulate filter is widely accepted throughout Europe, minimizing oil consumption has become a focal point in engine development. Above all, valve stem seals and cylinder head gaskets offer here the potential to keep exhaust gas emissions and oil consumption to a bare minimum. This article of Freudenberg Schwingungs- und Dichtungstechnik presents new sealing solutions. (orig.)

Pepin, F. [Freudenberg Dichtungs- und Schwingungstechnik GmbH und Co KG, Weinheim (Germany). Lead Center Zylinderkopfdichtungen

2007-04-15

276

High temperature gas-cooled reactor: gas turbine application study  

International Nuclear Information System (INIS)

The high-temperature capability of the High-Temperature Gas-Cooled Reactor (HTGR) is a distinguishing characteristic which has long been recognized as significant both within the US and within foreign nuclear energy programs. This high-temperature capability of the HTGR concept leads to increased efficiency in conventional applications and, in addition, makes possible a number of unique applications in both electrical generation and industrial process heat. In particular, coupling the HTGR nuclear heat source to the Brayton (gas turbine) Cycle offers significant potential benefits to operating utilities. This HTGR-GT Application Study documents the effort to evaluate the appropriateness of the HTGR-GT as an HTGR Lead Project. The scope of this effort included evaluation of the HTGR-GT technology, evaluation of potential HTGR-GT markets, assessment of the economics of commercial HTGR-GT plants, and evaluation of the program and expenditures necessary to establish HTGR-GT technology through the completion of the Lead Project

1980-01-01

277

Exhaust gas recirculation system  

Energy Technology Data Exchange (ETDEWEB)

An EGR assembly is disclosed of a sonic flow EGR valve and a fluid pressure actuated servo operated by air pressure modified by an air bleed device controlled in response to changes in carburetor venturi vacuum levels to provide EGR valve openings in proportion to engine air flow increases.

Rachedi, S.H.

1983-08-16

278

Optical fiber sensor for temperature measurement from 600 to 1900 C in gas turbine engines  

Science.gov (United States)

A temperature sensor system has been fabricated specifically for the harsh environment encountered in temperature measurement on gas turbine engines. Four components comprised the system: a thermally emissive source, a high temperature lightguide, a flexible optical cable and an electro-optic signal processor. The emissive source was located inside a sapphire rod so that the sapphire serves as both a lightguide and as a protective shroud. As the probe was heated, the thermal radiation from the emissive source increased with increasing temperature. The flexible optical cable was constructed with 200 micron core fiber and ruggedized for turbine engine applications. The electro-optic signal processor used the ratio of intensity in two wavelength intervals to determine a digital value of the temperature. The probe tip was operated above 1900 C in a low velocity propane flame and above 1500 C at Mach .37. Probe housings, optical cables, and signal processors were constructed and environmentally tested for the temperature and vibration experienced by turbine engine sensors. This technology was used to build an optical exhaust gas sensor for a General Electric Aircraft Engines F404 turbine. The four optical probes and optical cable were a functional replacement for four thermocouple probes. The system was ground tested for 50 hours with an excess of 1000 thermal cycles. This optical temperature sensor system measured gas temperature up to the operational limit of the turbine engine.

Tregay, G. W.; Calabrese, P. R.; Kaplin, P. L.; Finney, M. J.

1991-01-01

279

Present status of measures against automobile exhaust gas. 2. ; Alcohol-fueled car. Jidosha hai gas taisaku no genjo. 2. ; Alcohol jidosha  

Energy Technology Data Exchange (ETDEWEB)

This paper describes properties and features of methanol for alcohol-fueled cars, the present developmental conditions and future problems of methanol-fueled cars. In Brazil, about one million alcohol-fueled cars are fueled with gasoline mixed with 10-20% alcohol which is abundantly produced in this country for the purpose of saving gasoline. In Japan, M-100(100% methanol) and M-85(85% methanol+15% gasoline) are used in methanol-fueled cars, which amount to a total of 120 cars consisting of 60 Otto-type cars and 60 diesel type cars as of 1992, and M-100 methanol-fueled cars are not marketed but all used in a lease system for free testing. At present, the use of methanol-fueled cars should be considered as a means for solving the exhaust gas problem in Japan, but the attitude of the car industry for the research and development relating to this matter is not always satisfactory. 4 figs., 8 tabs.

1993-06-05

280

A proposal for the use of a very high temperature ceramic heat exchanger in gas turbine power production  

Energy Technology Data Exchange (ETDEWEB)

A highly efficient gas turbine plant is considered which uses ceramic heat exchanger components to take advantage of the very high turbine inlet temperatures available today. The materials used in the heat exchangers may have temperatures in excess of 1,000 C. Most Advanced Power Production Plant have the process fluid (steam or gases) usually enclosed inside tubes surrounded by combustion gases. A heat exchanger is proposed that has combustion gases on the inside of ceramic tubes in a shell and tube heat exchanger arrangement. The pressurized working fluid flows over the outside of the tubes in the shell. The ceramic tubes are thus kept in compression by the high pressure of this process fluid, utilizing the impressive resistance of ceramics to compressive force. The system described could be used in an exhaust-gas heat exchanger gas turbine power cycle to raise the thermal efficiency to approximately 65% (about 10% above that obtainable by conventional Combined Cycle Power Plant). The low pressure exhaust gases (say 1,000 C) from the secondary turbine are fed into the ceramic heat exchanger to heat the air from the high pressure compressor. This high temperature air is then fed to the combustor to provide gases at around 1,260 C/5 b for the turbines. The exhaust energy of the heat exchanger (200 C) could be used to raise steam for district heating purposes giving an excellent overall use of energy.

Smyth, R. [Univ. of Sheffield (United Kingdom). Dept. of Mechanical Engineering

1997-12-31

 
 
 
 
281

Effect of cooling the recirculated exhaust gases on diesel engine emissions  

International Nuclear Information System (INIS)

Although combustion is essential in most energy generation processes, it is one of the major causes of air pollution. Spiral fin exhaust pipes were designed to study the effect of cooling the recirculated exhaust gases (EGR) of Diesel engines on the chemical composition of the exhaust gases and the reduction in the percentages of pollutant emissions. The gases examined in this study were oxides of nitrogen (NOx), carbon dioxide (CO2) and carbon monoxide (CO). In addition, O2 concentration in the exhaust was measured. The two designs adopted in this study were exhaust pipes with solid and hollow fins around them. The first type uses air flow around the fins to cool the exhaust gases. The second type consists of hollow fins around the exhaust pipe to allow cooling water to flow in the hollow passage. Different combinations and arrangements of the solid and hollow fins exhaust pipes were used. It was found that decreasing the temperature of the EGR resulted in reductions in the oxides of nitrogen (NOx) and carbon dioxide (CO2) but increased the carbon monoxide (CO) in the exhaust gases. In addition, the oxygen (O2) concentration in the exhaust was decreased. As a general trend, the percentages of reduction in the NOx gas concentrations were lower than the percentages of increase in the CO emissions as a result of cooling the EGR of a Diesel engine by a heat exchanger. Using water as a cooling medium decreased the exhaust gases temperature and the amount of pollutants more than did air as a cooling medium. In a separate series of tests, increasing the cooled EGR ratios decreased the exhaust NOx but increased the particulate matter concentrations in the exhaust gases

2003-11-01

282

Model-based exhaust recirculation management in future air systems of supercharged diesel engines; Modellgestuetztes AGR-Management fuer zukuenftige Luftsysteme aufgeladener Dieselmotoren  

Energy Technology Data Exchange (ETDEWEB)

Diesel engines with high-pressure and low-pressure exhaust recirculation as well as exhaust treatment systems offer a perspective for meeting the specifications of future exhaust legislation. However, additional degrees of freedom in the air system and a higher number of control elements in such air pathways necessitate new engine control concepts to meet the more rigid requirements on controlled exhaust recirculation. Sensitive combustion processes including regeneration of exhaust treatment systems can only be implemented if several control variables, especially the air mass flow, the exhaust recirculation rate and the gas temperature in the intake tract meet the set values simultaneously and with high accuracy. Further, controlled low-pressure exhaust recirculation is to prevent undesirable condensation processes on the fresh air side of the air system. An integrated exhaust recirculation management was therefore developed on the basis of detailed model structures which meets these new requirements while making low demands in terms of parametrisation and resources. (orig.)

Heuck, M.; Feldt, M.; Eichhorn, M.; Horn, A. [IAV GmbH, Gifhorn (Germany)

2008-07-01

283

Hydrogen production from biomass pyrolysis gas via high temperature steam reforming process  

International Nuclear Information System (INIS)

Full text: The aim of this work has been undertaken as part of the design of continuous hydrogen production using the high temperature steam reforming process. The steady-state test condition was carried out using syngas from biomass pyrolysis, whilst operating at high temperatures between 600 and 1200 degree Celsius. The main reformer operating parameters (e.g. temperature, resident time and steam to biomass ratio (S/B)) have been examined in order to optimize the performance of the reformer. The operating temperature is a key factor in determining the extent to which hydrogen production is increased at higher temperatures (900 -1200 degree Celsius) whilst maintaining the same as resident time and S/B ratio. The effects of exhaust gas composition on heating value were also investigated. The steam reforming process produced methane (CH4) and ethylene (C2H4) between 600 to 800 degree Celsius and enhanced production ethane (C2H6) at 700 degree Celsius. However carbon monoxide (CO) emission was slightly increased for higher temperatures all conditions. The results show that the use of biomass pyrolysis gas can produce higher hydrogen production from high temperature steam reforming. In addition the increasing reformer efficiency needs to be optimized for different operating conditions. (author)

2010-07-26

284

Effect of Exhaust Gas Recirculation on the Dual Fuel Combustion of Gasoline and CNG by Compression Ignition  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Homogeneous Charge Compression Ignition (HCCI) is a combustion process that promises the combination of diesel like efficiencies and very low NOx emissions. The major issues with HCCI are high heat release rates, lack of combustion control and high CO and HC emissions. Operating HCCI with two fuels of different properties and recirculation of exhaust gases are effective strategies of promoting and controlling autoignition. This study discusses the effects of EGR on the combustion characterist...

Naveenchandran, P.; Noraz Al-Khairi; Raja Shahzad; Aziz, A. Rashid A.

2011-01-01

285

Application of modern online instrumentation for chemical analysis of gas and particulate phases of exhaust at the European Commission heavy-duty vehicle emission laboratory.  

Science.gov (United States)

The European Commission recently established a novel test facility for heavy-duty vehicles to enhance more sustainable transport. The facility enables the study of energy efficiency of various fuels/scenarios as well as the chemical composition of evolved exhaust emissions. Sophisticated instrumentation for real-time analysis of the gas and particulate phases of exhaust has been implemented. Thereby, gas-phase characterization was carried out by a Fourier transform infrared spectrometer (FT-IR; carbonyls, nitrogen-containing species, small hydrocarbons) and a resonance-enhanced multiphoton ionization time-of-flight mass spectrometer (REMPI-TOFMS; monocyclic and polycyclic aromatic hydrocarbons). For analysis of the particulate phase, a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS; organic matter, chloride, nitrate), a condensation particle counter (CPC; particle number), and a multiangle absorption photometer (MAAP; black carbon) were applied. In this paper, the first application of the new facility in combination with the described instruments is presented, whereby a medium-size truck was investigated by applying different driving cycles. The goal was simultaneous chemical characterization of a great variety of gaseous compounds and particulate matter in exhaust on a real-time basis. The time-resolved data allowed new approaches to view the results; for example, emission factors were normalized to time-resolved consumption of fuel and were related to emission factors evolved during high speeds. Compounds could be identified that followed the fuel consumption, others showed very different behavior. In particular, engine cold start, engine ignition (unburned fuel), and high-speed events resulted in unique emission patterns. PMID:21126058

Adam, T W; Chirico, R; Clairotte, M; Elsasser, M; Manfredi, U; Martini, G; Sklorz, M; Streibel, T; Heringa, M F; Decarlo, P F; Baltensperger, U; De Santi, G; Krasenbrink, A; Zimmermann, R; Prevot, A S H; Astorga, C

2011-01-01

286

Thermoelectric generators incorporating phase-change materials for waste heat recovery from engine exhaust  

Energy Technology Data Exchange (ETDEWEB)

Thermoelectric devices, intended for placement in the exhaust of a hydrocarbon fuelled combustion device and particularly suited for use in the exhaust gas stream of an internal combustion engine propelling a vehicle, are described. Exhaust gas passing through the device is in thermal communication with one side of a thermoelectric module while the other side of the thermoelectric module is in thermal communication with a lower temperature environment. The heat extracted from the exhaust gasses is converted to electrical energy by the thermoelectric module. The performance of the generator is enhanced by thermally coupling the hot and cold junctions of the thermoelectric modules to phase-change materials which transform at a temperature compatible with the preferred operating temperatures of the thermoelectric modules. In a second embodiment, a plurality of thermoelectric modules, each with a preferred operating temperature and each with a uniquely-matched phase-change material may be used to compensate for the progressive lowering of the exhaust gas temperature as it traverses the length of the exhaust pipe.

Meisner, Gregory P; Yang, Jihui

2014-02-11

287

Material technologies supporting purification of exhausted gas. Diesel particulate filters. Haiki joka wo sasaeru zairyo gijutsu. Diesel patikyureto filter ni tsuite  

Energy Technology Data Exchange (ETDEWEB)

For aftertreatment of exhaust gas from diesel engines, the development of various kinds of traps called diesel particulate filters (DPF) is now in progress. A DPF collects particulates in exhaust gas effectively on the one hand, but on the other hand, it needs a complicated system for reactivation of the filter. In this article, various kinds of DPF's, their reactivation system, and the dependability of combustion reactivation of the extruded cordierite honeycomb type DPF are described. The features of 6 kinds of so far developed main DPF traps including metal wiremesh filter, ceramic fiber laminated filter, ceramic form filter are explained, and as the reactivation methods of DPF's, five kinds of reactivation systems including the natural reactivation system and the electric heater reactivation system are introduced. In addition, concerning the diesel burner reactivation of the honeycomb type DPF and the combustion reactivity with an electric heater, the evaluation results of their dependability are explained. 28 refs., 10 figs.

Nakamura, T.; Kitagawa, J.

1994-05-01

288

High-temperature Gas Reactor (HTGR)  

Science.gov (United States)

General Atomics (GA) has over 35 years experience in prismatic block High-temperature Gas Reactor (HTGR) technology design. During this period, the design has recently involved into a modular have been performed to demonstrate its versatility. This versatility is directly related to refractory TRISO coated - particle fuel that can contain any type of fuel. This paper summarized GA's fuel cycle studies individually and compares each based upon its cycle sustainability, proliferation-resistance capabilities, and other performance data against pressurized water reactor (PWR) fuel cycle data. Fuel cycle studies LEU-NV;commercial HEU-Th;commercial LEU-Th;weapons-grade plutonium consumption; and burning of LWR waste including plutonium and minor actinides in the MHR. results show that all commercial MHR options, with the exception of HEU-TH, are more sustainable than a PWR fuel cycle. With LEU-NV being the most sustainable commercial options. In addition, all commercial MHR options out perform the PWR with regards to its proliferation-resistance, with thorium fuel cycle having the best proliferation-resistance characteristics.

Abedi, Sajad

2011-06-01

289

Experimental Study of Heat Transfer to Small Cylinders in a Subsonic, High-temperature Gas Stream  

Science.gov (United States)

A Nusselt-Reynolds number relation for cylindrical thermocouple wires in crossflow was obtained from the experimental determination of time constants. Tests were conducted in exhaust gas over a temperature range of 2000 to 3400 R, a Mach number range of 0.3 to 0.8, and a static-pressure range from 2/3 to 1-1/3 atmospheres, yielding a Reynolds number range of 450 to 3000. The correlation obtained is Nu=(0.428 plus or minus 0.003) times the square root of Re* with average deviations of a single observation of 8.5 percent. This relation is the same as one previously reported for room-temperature conditions.

Glawe, George E; Johnson, Robert C

1957-01-01

290

Plastics in high temperature quenches of flue gas cleaning units  

Energy Technology Data Exchange (ETDEWEB)

Waste incinerators plants, like electricity production plants are forced to invest in air pollution control equipment, i.e. flue gas cleaning units. In recent years this has led to the use of (high temperature resistant) fiber reinforced plastics for flue gas scrubbers and high temperature quenches. Some feed back on the experiences will be given along with recent improvements in application.

Bruijn, J.C.M. de [Delft Univ. of Technology (Netherlands). Faculty of Industrial Design Engineering

1997-08-01

291

Optogalvanic Measurements of Gas Temperature in the Cathode Fall.  

Science.gov (United States)

Optogalvanic diagnostics are used to determine the electric field and the absolute gas temperature as a function of position in the cathode fall of an abnormal glow discharge. Gas temperature in the cathode fall at modest current densities are as much as ...

D. K. Doughty E. A. Den Hartog J. E. Lawler

1985-01-01

292

Estimated times to exhaustion and power outputs at the gas exchange threshold, physical working capacity at the rating of perceived exertion threshold, and respiratory compensation point.  

Science.gov (United States)

The purposes of this study were to compare the power outputs and estimated times to exhaustion (T(lim)) at the gas exchange threshold (GET), physical working capacity at the rating of perceived exertion threshold (PWC(RPE)), and respiratory compensation point (RCP). Three male and 5 female subjects (mean ± SD: age, 22.4 ± 2.8 years) performed an incremental test to exhaustion on an electronically braked cycle ergometer to determine peak oxygen consumption rate, GET, and RCP. The PWC(RPE) was determined from ratings of perceived exertion data recorded during 3 continuous workbouts to exhaustion. The estimated T(lim) values for each subject at GET, PWC(RPE), and RCP were determined from power curve analyses (T(lim) = ax(b)). The results indicated that the PWC(RPE) (176 ± 55 W) was not significantly different from RCP (181 ± 54 W); however, GET (155 ± 42 W) was significantly less than PWC(RPE) and RCP. The estimated T(lim) for the GET (26.1 ± 9.8 min) was significantly greater than PWC(RPE) (14.6 ± 5.6 min) and RCP (11.2 ± 3.1 min). The PWC(RPE) occurred at a mean power output that was 13.5% greater than the GET and, therefore, it is likely that the perception of effort is not driven by the same mechanism that underlies the GET (i.e., lactate buffering). Furthermore, the PWC(RPE) and RCP were not significantly different and, therefore, these thresholds may be associated with the same mechanisms of fatigue, such as increased levels of interstitial and (or) arterial [K?]. PMID:22716291

Bergstrom, Haley C; Housh, Terry J; Zuniga, Jorge M; Camic, Clayton L; Traylor, Daniel A; Schmidt, Richard J; Johnson, Glen O

2012-10-01

293

Facility for impurity separation in high temperature coal gas; Koon sekitan gas no fujunbutsu bunri sochi  

Energy Technology Data Exchange (ETDEWEB)

This invention relates a fuel cell to generate power using fuel gas supplied from a coal gasification plant, and aims to present a facility to remove the impurity from high temperature coal gas. The previous high temperature gas purification system does not remove the impurity sufficiently and the low temperature gas purification system also has problems in low removal efficiency and expense and these systems are inadequate for a fuel cell. The facility of this invention is composed of a turbine apparatus to expand the high temperature coal gas to lower the temperature and to generate power and an apparatus to separate the impurity from the coal gas of a lowered temperature and pressure. This separation apparatus is composed of a processing bed to remove chlorides, a particle bed of zinc oxide to adsorb and separate sulfur and sulfur compounds and a filter to remove the particulate impurity. 1 fig.

Cederquist, R. [Connecticut (United States); Preston, J. [Connecticut (United States); Freud, F. [Texas (United States); Chan, F. [Texas (United States)

1995-09-05

294

A comparative study of the elemental composition of the exhaust emissions of cars powered by liquefied petroleum gas and unleaded petrol  

Science.gov (United States)

Elements emitted from the exhausts of new Ford Falcon Forte cars powered by unleaded petrol (ULP) and liquefied petroleum gas (LPG) were measured on a chassis dynamometer. The measurements were carried out in February, June and August 2001, and at two steady state driving conditions (60 and 80 km h -1). Thirty seven elements were quantified in the exhaust samples by inductively coupled plasma mass spectrometry (ICPMS). The total emission factors of the elements from the exhausts of ULP cars were higher than those of LPG cars at both engine speeds even though high variability in the exhaust emissions from different cars was noted. The effect of the operating conditions such as mileage of the cars, engine speed, fuel and lubricating oil compositions on the emissions was studied. To investigate the effects of these conditions, multivariate data analysis methods were employed including exploratory principal component analysis (PCA), and the multi-criteria decision making methods (MCDM), preference ranking organization method for enrichment evaluation (PROMETHEE) and geometrical analysis for interactive aid (GAIA), for ranking the cars on the basis of the emission factors of the elements. PCA biplot of the complete data matrix showed a clear discrimination of the February, June and August emission test results. In addition, (i) platinum group elements (PGE) emissions were separated from each other in the three different clusters viz. Pt with February, Pd with June and Rh with August; (ii) the motor oil related elements, Zn and P, were particularly associated with the June and August tests (these vectors were also grouped with V, Al and Cu); and (iii) highest emissions of most major elements were associated with the August test after the cars have recorded their highest mileage. Extensive analysis with the aid of the MCDM ranking methods demonstrated clearly that cars powered by LPG outperform those powered by ULP. In general, cars tested in June perform better than those tested in August, which suggested that mileage was the key criterion of car performance on the basis of elemental emission factors.

Lim, McKenzie C. H.; Ayoko, Godwin A.; Morawska, Lidia; Ristovski, Zoran D.; Jayaratne, E. Rohan; Kokot, Serge

295

Utilisation of CO2, fixation of nitrogen and exhaust gas cleaning in electric discharge with electrode catalysis  

International Nuclear Information System (INIS)

The method reported here provides a contribution to CO2 utilisation, nitrogen fixation and combustion exhaust cleaning using synergetic effect of electric discharge with heterogeneous catalysis on electrodes. The efficiency of CO2 removal is about 40-65%. The process of CO2 removal is always accompanied by NOx, VOC, SX and other component removal and is connected with O2 formation. The final product of process is powder with fractal microstructure, low specific weight, water insoluble suitable for use as nitrogen containing fertilizer. The main component (95%) of solid product is amorphous condensate of amino acids with about 5% of metal organic compound with catalytic properties. The condensate has character of statistical proteinoid. Its creation seems to play important role during formation of life in pre-biotic Earth

2001-02-18

296

Utilisation of CO{sub 2}, fixation of nitrogen and exhaust gas cleaning in electric discharge with electrode catalysis  

Energy Technology Data Exchange (ETDEWEB)

The method reported here provides a contribution to CO{sub 2} utilisation, nitrogen fixation and combustion exhaust cleaning using synergetic effect of electric discharge with heterogeneous catalysis on electrodes. The efficiency of CO{sub 2} removal is about 40-65%. The process of CO{sub 2} removal is always accompanied by NO{sub x}, VOC, SX and other component removal and is connected with O{sub 2} formation. The final product of process is powder with fractal microstructure, low specific weight, water insoluble suitable for use as nitrogen containing fertilizer. The main component (95%) of solid product is amorphous condensate of amino acids with about 5% of metal organic compound with catalytic properties. The condensate has character of statistical proteinoid. Its creation seems to play important role during formation of life in pre-biotic Earth.

Marcela, M.; Imrich, M.; Mario, J. [Komenskeho Univ., Bratislava (Slovakia). Dept. of Physics

2001-07-01

297

40 CFR 86.1309-90 - Exhaust gas sampling system; Otto-cycle and non-petroleum-fueled engines.  

Science.gov (United States)

...gas sampling system; Otto-cycle and non-petroleum-fueled...Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines...gas sampling system; Otto-cycle and non-petroleum-fueled...total volume is measured by counting the revolutions made...

2009-07-01

298

3-D stream and vortexes in an urban canopy layer and transport of motor vehicle exhaust gas-wind tunnel experiment  

Energy Technology Data Exchange (ETDEWEB)

The stream in the urban canopy layer is thought to be complicated. Therefore, modelling the vortexes in street canyons is an attractive subject for predicting the transport of motor vehicle exhaust gas. For predicting the concentration of air pollutants within a street canyon, one or twin vortex model is used in OSPM (Hertel and Berkowicz, 1989). The vortex is created on the vertical cross-section of the street canyons (''vertical vortex''). The axis of rotation is along a street. It transports and mixes air pollutants emitted in the street canyon. However the OSPM is applicable to a 2-D street which has large distance between intersections. The effect of the transport of air pollutants through intersecting streets is not included in the model. The effect of the intersecting streets is important to predict the dispersion in the vicinity of the street. The OMG model (Kono and Ito, 1990), a micro scale dispersion model which predict the dispersion of motor vehicle exhaust gas within 200 m from a street, includes the effect of intersecting streets in the height of an imaginary boundary, below which buildings interrupt the horizontal transport. If the intervals between buildings along a street are small, the height of imaginary boundary is almost same as the height of buildings. If the intervals between buildings are larger, the height of imaginary boundary becomes lower than the building height. The OMG model employs a volume-source to model the mixing of pollutants within the street canyon. The ratio of the thickness of the volume source to the building height along the street varies with intervals between buildings. This paper presents the wind tunnel experiments which were conducted by using a tracer for visualizing the transport. It visualized the stream and the vortexes in street canyons for several wind directions, and several dimensions of building length, height and street width. The dispersion of air pollutants in the vicinity of a street was discussed. (orig.)

Kono, H.; Kusunoki, K. [Hyogo Prefectural Univ., Hyogo (Japan)

2004-07-01

299

Method for high temperature mercury capture from gas streams  

Energy Technology Data Exchange (ETDEWEB)

A process to facilitate mercury extraction from high temperature flue/fuel gas via the use of metal sorbents which capture mercury at ambient and high temperatures. The spent sorbents can be regenerated after exposure to mercury. The metal sorbents can be used as pure metals (or combinations of metals) or dispersed on an inert support to increase surface area per gram of metal sorbent. Iridium and ruthenium are effective for mercury removal from flue and smelter gases. Palladium and platinum are effective for mercury removal from fuel gas (syngas). An iridium-platinum alloy is suitable for metal capture in many industrial effluent gas streams including highly corrosive gas streams.

Granite, Evan J. (Wexford, PA); Pennline, Henry W. (Bethel Park, PA)

2006-04-25

300

Effects of inlet distortion on gas turbine combustion chamber exit temperature profiles  

Science.gov (United States)

Damage to a nozzle guide vane or blade, caused by non-uniform temperature distributions at the combustion chamber exit, is deleterious to turbine performance and can lead to expensive and time consuming overhaul and repair. A test rig was designed and constructed for the Allison 250-C20B combustion chamber to investigate the effects of inlet air distortion on the combustion chamber's exit temperature fields. The rig made use of the engine's diffuser tubes, combustion case, combustion liner, and first stage nozzle guide vane shield. Rig operating conditions simulated engine cruise conditions, matching the quasi-non-dimensional Mach number, equivalence ratio and Sauter mean diameter. The combustion chamber was tested with an even distribution of inlet air and a 4% difference in airflow at either side. An even distribution of inlet air to the combustion chamber did not create a uniform temperature profile and varying the inlet distribution of air exacerbated the profile's non-uniformity. The design of the combustion liner promoted the formation of an oval-shaped toroidal vortex inside the chamber, creating localized hot and cool sections separated by 90° that appeared in the exhaust. Uneven inlet air distributions skewed the oval vortex, increasing the temperature of the hot section nearest the side with the most mass flow rate and decreasing the temperature of the hot section on the opposite side. Keywords: Allison 250, Combustion, Dual-Entry, Exit Temperature Profile, Gas Turbine, Pattern Factor, Reverse Flow.

Maqsood, Omar Shahzada

 
 
 
 
301

Denuder for measuring emissions of gaseous organic exhaust gas constituents; Denuder zur Emissionsmessung von gasfoermigen organischen Abgasinhaltsstoffen  

Energy Technology Data Exchange (ETDEWEB)

Industrial plants which emit carcinogenic or other noxious substances should be given top priority in any policy to ward off harmful environmental effects. This also applies to many volatile and semi-volatile air constituents such as volatile aliphatic carbonyls or amines. To date there are no satisfactory methods for determining trace organic components of exhaust gases. It is true that aldehydes are considered in the VDI Guideline 3862, but the measuring methods given there are based on absorption in liquids and are accordingly difficult to use and show a high cross-sensitivity for other substances. No VDI Guideline exists to date on amine emissions. In view of the complexity of exhaust gases a selective enrichment of certain families of substances would appear indicated. Sampling trouble could be reduced if it was possible only to accumulate the gaseous phase, or even just one family of gaseous constituents. A particularly suitable air sampling method is that of diffusion separation. These diffusion separators (denuders) are well known as a powerful measuring system which is able to accumulate trace pollutants in the outside air. The purpose of the present study was to find out whether the concept of diffusion separation is also applicable to emission monitoring, and in particular whether it is suitable for detecting volatile aliphatic aldehydes and amines (primary and secondary) at extremely low concentrations (<10 ppb). (orig./SR) [Deutsch] Fuer Anlagen mit Emissionen von krebserzeugenden und gesundheitsgefaehrdenden Stoffen ergibt sich ein besonderer Handlungsbedarf zum Schutz vor schaedlichen Umwelteinwirkungen. Zu diesen Stoffen gehoeren auch viele leicht- und mittelfluechtigen Luftinhaltsstoffe, wie z.B. die leichtfluechtigen aliphatischen Carbonyle oder Amine. Fuer organische Komponenten, die nur in geringen Konzentrationen im Abgas vorkommen, existieren bisher keine zufriedenstellenden Messverfahren. Fuer die Aldehyde liegt zwar die VDI-Richtlinie 3862 vor, diese Messverfahren beruhen aber auf dem Absorptionsprinzip in Fluessigkeiten, das umstaendlich zu handhaben ist und eine grosse Querempfindlichkeit zu anderen Stoffen besitzt. Fuer die Emissionsmessung von Aminen gibt es derzeit noch keine VDI-Richtlinie. Aufgrund der Komplexitaet des Mediums Abgas ist eine selektive Anreicherung bestimmter Substanzklassen wuenschenswert. So koennen Stoerungen bei der Probenahme verringert werden, indem nur die Gasphase, und hier moeglichst nur eine Substanzklasse, selektiv angereichert wird. Dazu eignet sich besonders die Luftprobenahme auf dem Prinzip der Diffusionsabscheidung. Diese Diffusionsabscheider (Denuder) sind ein bekanntes Messsystem zur nachweisstarken und selektiven Anreicherung von Spurenschadstoffen in der Aussenluft. In diesem Vorhaben soll nun dieses Konzept der Diffusionsabscheidung auf die Anwendbarkeit im Emissionsbereich ueberprueft werden, speziell zur Erfassung der leichtfluechtigen aliphatischen Aldehyde und Amine (primaere und sekundaere) mit extrem niedrigen Nachweisgrenzen (<10 ppb). (orig./SR)

Gerchel, B.; Jockel, W.; Kallinger, G.; Niessner, R.

1997-05-01

302

Emission of carcinogenic components with automobile exhausts.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Different sampling methods for mutagenic polynuclear aromatic hydrocarbons (PAH) are described. These methods involve either direct sampling of raw exhausts which prior to filtering are cooled in a condenser, or filter sampling of exhausts diluted in a tunnel. The relevance of gas-phase PAHs of samples from diluted exhausts is discussed; methods used are either adsorbents (XAD-2) or cryogenic condensation. The emission of benzo(a)pyrene and certain other PAHs is reported from vehicles using d...

1983-01-01

303

Temperature distribution measurement in the hot gas duct of HENDEL  

International Nuclear Information System (INIS)

The HENDEL (Helium Engineering Demonstration Loop) which was completed on March, 1982, has been operated 3 times so far, including a test operation when it was handed over to JAERI. In the main part of HENDEL which is called a Mother + Adapter (M+A) loop, a hot gas duct through which helium gas of 1000"0C, 40 atm, 4kg/s flows is installed. This report deals with the measurement and evaluation of temperature distribution of the hot gas duct. The maximum surface temperature of the hot gas duct was 230"0C, which is low enough, compared with an allowable design temperature of 350"0C. The effective thermal conductivity of the insulation inside the hot gas duct was found to be 0.40 - 0.49 kcal/mh"0C. (author)

1983-01-01

304

Nitrogen charge temperature prediction in a gas lift valve  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The operation of a class of retrievable gas-lift valves (GLV) is controlled by the axial movement of a bellows. One force acting on the bellows is due to the pressure exerted by the nitrogen gas contained in the GLV dome. It depends on the nitrogen temperature, which is influenced by both the produc [...] tion fluid and the injection gas temperatures in the well. This work investigated this dependence for a GLV installed in a side pocket mandrel tube. Three independent procedures were used for this purpose, comprising a compact thermal model, an experimental investigation with a thermal mockup and a numerical analysis. From these, a correlation for the nitrogen temperature was proposed, based on the local production fluid and injection gas temperatures, and on their convective coefficients with the mandrel tube surfaces.

Marcelo M., Ganzarolli; Carlos A. C., Altemani.

305

Nitrogen charge temperature prediction in a gas lift valve  

Directory of Open Access Journals (Sweden)

Full Text Available The operation of a class of retrievable gas-lift valves (GLV is controlled by the axial movement of a bellows. One force acting on the bellows is due to the pressure exerted by the nitrogen gas contained in the GLV dome. It depends on the nitrogen temperature, which is influenced by both the production fluid and the injection gas temperatures in the well. This work investigated this dependence for a GLV installed in a side pocket mandrel tube. Three independent procedures were used for this purpose, comprising a compact thermal model, an experimental investigation with a thermal mockup and a numerical analysis. From these, a correlation for the nitrogen temperature was proposed, based on the local production fluid and injection gas temperatures, and on their convective coefficients with the mandrel tube surfaces.

Marcelo M. Ganzarolli

2010-03-01

306

Determining gas rate distribution from temperature and pressure profiles in gas well  

Directory of Open Access Journals (Sweden)

Full Text Available A simple and effective method of the gas rate prediction from temperature and pressure data is discussed in this paper. Solving the inverse problem allows determination of the flow rate by matching the gas pressure and temperature distributions with measured profiles. Results of field data treatment show good agreement with the model prediction.

Barrett Emile

2012-01-01

307

Determining gas rate distribution from temperature and pressure profiles in gas well  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A simple and effective method of the gas rate prediction from temperature and pressure data is discussed in this paper. Solving the inverse problem allows determination of the flow rate by matching the gas pressure and temperature distributions with measured profiles. Results of field data treatment show good agreement with the model prediction.

Barrett Emile; Abbasy Imran; Wu Chii-Rong; You Zhenjiang; Bedrikovetsky Pavel

2012-01-01

308

A new algorithm predicts pressure and temperature profiles of gas/gas-condensate transmission pipelines  

Energy Technology Data Exchange (ETDEWEB)

The main objective of the present study has been the development of a relatively simple analytical algorithm for predicting flow temperature and pressure profiles along the two-phase, gas/gas-condensate transmission pipelines. Results demonstrate the ability of the method to predict reasonably accurate pressure gradient and temperature gradient profiles under operating conditions. (author)

Mokhatab, Saied [OIEC - Oil Industries' Engineering and Construction Group, Tehran (Iran, Islamic Republic of); Vatani, Ali [University of Tehran (Iran, Islamic Republic of)

2003-07-01

309

Pion gas viscosity at low temperature and density  

CERN Document Server

By using Chiral Perturbation Theory and the Uehling-Uhlenbeck equation we compute the viscosity of a pion gas, in the low temperature and low density regime, in terms of the temperature, and the pion fugacity. The viscosity turns out to be proportional to the squared root of the temperature over the pion mass. Next to leading corrections are proportional to the temperature over the pion mass to the 3/2.

Dobado, A; Dobado, Antonio; Santalla, Silvia N.

2002-01-01

310

High-Temperature Desulfurization of Low-Btu-Gas.  

Science.gov (United States)

The report describes and gives results of economic studies of a process for desulfurizing low-Btu fuel gas. The gas is first desulfurized at high temperature in a fluidized bed of half-calcined dolomite. It is then cooled to 700 C and passed through high-...

B. J. Pasek E. Gorin G. P. Curran M. Pell

1977-01-01

311

The effects of strong temperature anisotropy on the kinetic structure of collisionless slow shocks and reconnection exhausts. I. Particle-in-cell simulations  

International Nuclear Information System (INIS)

A 2-D Riemann problem is designed to study the development and dynamics of the slow shocks that are thought to form at the boundaries of reconnection exhausts. Simulations are carried out for varying ratios of normal magnetic field to the transverse upstream magnetic field (i.e., propagation angle with respect to the upstream magnetic field). When the angle is sufficiently oblique, the simulations reveal a large firehose-sense (P||>Pperpendicular) temperature anisotropy in the downstream region, accompanied by a transition from a coplanar slow shock to a non-coplanar rotational mode. In the downstream region the firehose stability parameter ?=1-?0(P||-Pperpendicular)/B2 tends to plateau at 0.25. This balance arises from the competition between counterstreaming ions, which drive ? down, and the scattering due to ion inertial scale waves, which are driven unstable by the downstream rotational wave. At very oblique propagating angles, 2-D turbulence also develops in the downstream region.

2011-06-01

312

Workbook for predicting short-term atmospheric dispersion of reciprocating engine exhaust emissions from natural gas compressor stations  

Energy Technology Data Exchange (ETDEWEB)

Based on the US Environmental Protection Agency's industrial source complex (ISC) dispersion model, the calculations presented in this workbook represent the first available simplified dispersion-modeling procedure to account for the downwash of plumes from short stacks, specifically those from reciprocating engines in compressor stations. The methodology involved compiling data on the emission source characteristics, selecting pertinent meteorological data, and calculating the plume rise, the ground-level pollutant concentrations, and the additive effects of plumes. Also included are sample calculations and a sensitivity analysis of the input parameters. The procedure considers only reciprocating-engine emissions, not effluents from gas turbines, heaters, or gas-treatment facilities.

1980-01-01

313

Hadron resonance gas and nonperturbative QCD vacuum at finite temperature  

CERN Document Server

We study the nonperturbative QCD vacuum with two light quarks at finite temperature in the framework of hadron resonance gas. Temperature dependence of the quark and gluon condensates in the confined phase are obtained. We demonstrate that the quark condensate and one half (chromo-electric component) of gluon condensate evaporate at the same temperature, which corresponds to the temperature of quark-hadron phase transition. Critical temperature is T_c~190 MeV when temperature shift of hadron masses is taken into account.

Agasian, N O; Agasian, Nikita O.; Fedorov, Sergei M.

2003-01-01

314

Development history of the gas turbine modular high temperature reactor  

International Nuclear Information System (INIS)

The development of the high temperature gas cooled reactor (HTGR) as an environmentally agreeable and efficient power source to support the generation of electricity and achieve a broad range of high temperature industrial applications has been an evolutionary process spanning over four decades. This process has included ongoing major development in both the HTGR as a nuclear energy source and associated power conversion systems from the steam cycle to the gas turbine. This paper follows the development process progressively through individual plant designs from early research of the 1950s to the present focus on the gas turbine modular HTGR. (author)

2001-08-01

315

Nitrogen charge temperature prediction in a gas lift valve  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The operation of a class of retrievable gas-lift valves (GLV) is controlled by the axial movement of a bellows. One force acting on the bellows is due to the pressure exerted by the nitrogen gas contained in the GLV dome. It depends on the nitrogen temperature, which is influenced by both the production fluid and the injection gas temperatures in the well. This work investigated this dependence for a GLV installed in a side pocket mandrel tube. Three independent procedures were used for this ...

2010-01-01

316

Bio-desulfurization (THIOPAQ{sup TM}) process for waste water and exhaust gas; Haisui, Haigasu no baio datsuryu (THIOPAQ{sup TM}) purosesu  

Energy Technology Data Exchange (ETDEWEB)

Restrictions for sulfur contents in petroleum products are becoming severer, and in Europe, sulfur content of diesel oil was decided to be restricted less than 50 ppm from 2005. Along with this situation, Japan is going to examine a current standard of 500 ppm for a further severer standard. With this sulfur content restriction, increases presumed in hydrogen sulfide and sulfur compounds in exhaust gases discharged from petroleum refining processes, BOD and COD in waste water, treatment quantities of scrapping solution and waste soda discharged from hydrogen sulfide scrapping facilities. THIOPAQ process is a process in which hydrogen sulfide, sulfur oxides and sulfides are converted to sulfur and sulfate and removed utilizing microorganism. In this process, it is necessary that sulfur compounds are all dissolved in water. In treating gas, gas is first sent to scrapping section to remove hydrogen sulfide and sulfur compounds, afterwards bio treatment of waste scrapping solution containing sulfur compounds or waste soda is carried out. The central part of this process is bio reactive tower that contains only microorganism in order to maximize sulfide conversion activity. The first facility of THIOPAQ process was constructed in paper mill in 1993, the first facility in petroleum refinery will start operation in the latter half of 2000. (NEDO)

Kawamura, T. [Nikki Universal Co., Ltd., Tokyo (Japan)

2000-07-01

317

Discussion of the effects of recirculating exhaust air on performance and efficiency of a typical microturbine  

International Nuclear Information System (INIS)

This paper reports on a specific phenomenon, noticed during steam injection experiments on a microturbine. During the considered experiments, measurements indicated an unsteady inlet air temperature of the compressor, resulting in unstable operation of the microturbine. Non-continuous exhaust air recirculation was a possible explanation for the observed behaviour of the microturbine. The aim of this paper is to investigate and demonstrate the effects of exhaust recirculation on a microgasturbine. Depending on wind direction, exhaust air re-entered the engine, resulting in changing inlet conditions which affects the operating regime of the microturbine. For this paper, a series of experiments were performed in the wind tunnel. These series of experiments allowed investigation of the effect of the wind direction on flue gasses flow. Next to the experiments, steady-state simulations of exhaust recirculation were performed in order to study the effect of exhaust recirculation on thermodynamic performance of the microturbine. Dynamic simulations of the non-continuous recirculation revealed the effects of frequency and amplitude on average performance and stability. Results from simulations supported the important impact of exhaust recirculation. Wind tunnel tests demonstrated the influence of the wind direction on recirculation and revealed the necessity to heighten the stack, thus preventing exhaust recirculation. -- Highlights: ? Unstable operation of a T100 microturbine during steam injection tests was noticed, caused by exhaust gas recirculation. ? Wind tunnel tests were performed to study the effect of the wind direction on the recirculation process. ? Steady-state simulations to investigate the effect of exhaust gas recirculation on thermodynamic performance. ? Dynamic simulations to reveal effects of frequency and amplitude on average performance and stability. ? Wind tunnel tests revealed the necessity to heighten the stack to prevent exhaust recirculation.

2012-09-01

318

Gas extractor  

Energy Technology Data Exchange (ETDEWEB)

A gas extractor for processing crude oil to provide the energy to power an internal combustion engine driving a conventional oil pumping unit. The extractor comprises a vertical tank, an extractor chamber, an exhaust gas pipe passing through the tank with a plurality of baffle pans mounted longitudinally thereon; a crude oil reservoir in the top of the tank, valve means controlling the rate of oil flow from the reservoir to the upper baffle pan; means to vary the amount of exhaust gases passed through the exhaust pipe to control the temperature of the extractor chamber; a gas outlet passage, air inlet passage and oil drain passages in the extractor chamber, each adjacent baffle pan being oppositely tilted and having a drain opening at its lower side whereby the oil passing through the extractor flows across each adjacent oil pan before being drained from the extractor.

Stevenson, C. K.

1985-04-23

319

Coal/biomass cogasification and high temperature gas cleaning  

Energy Technology Data Exchange (ETDEWEB)

A report is presented on the cogasification of coal and biomass in a downdraught fixed-bed gasifier and on the high temperature removal of halides from the fuel gas produced. Air-blown downdraught gasifiers are considered as an interesting option especially for small and intermediate scale on-site fuel gas generation using high volatile feedstocks. The current test programme focuses on the effect of the partial replacement of the coal feedstock by two different biomass feedstocks - Meranti wood waste and straw pellets, on gasifier operability and fuel gas composition. For dry halide removal, several sorbents were evaluated based on literature data, thermodynamic calculations, and on laboratory and bench-scale experiments at atmospheric pressure. The evaluation was mainly focused on dry halide removal at a temperature level of 350-400{degree} C in a separate process located upstream of the desulphurisation process in an integrated system for high temperature gas cleaning. 11 refs., 8 figs., 11 tabs.

Kiel, J.H.A.; Bos, A.; Uil, H. den; Plaum, J.M. [Netherlands Energy Research Foundation ECN, Petten (Netherlands). Business Unit ECN Fossil Fuels

1995-12-31

320

Laboratory spectra of gas-phase coronene at elevated temperatures  

Science.gov (United States)

Gas-phase infrared spectra of coronene from 4000 to 400/cm are presented in emission and absorption at temperatures from 350 to 450 C. Peak positions are compared to KBr pellet data and to a previously published neon matrix-isolated coronene spectrum. Relative feature strengths are analyzed and used to estimate a temperature of interstellar PAHs assuming thermal emission.

Kurtz, J.

1992-01-01

 
 
 
 
321

Development and testing of non-manipulable technical measures for speed and noise limitation and simultaneous reduction of exhaust gas and fuel consumptionof motor-assisted two-wheelers. Phase 1. Entwicklung und Erprobung nicht manipulierbarer technischer Massnahmen zur Geschwindigkeitsbegrenzung und Geraeuschbegrenzung motorisierter Zweiraeder bei gleichzeitiger Abgas- und Verbrauchsminderung. Phase 1  

Energy Technology Data Exchange (ETDEWEB)

Motor-assisted bikes (test vehicles) were equipped with modified drive aggregates in order to reduce the pollutant content of the exhaust gas and the noise level. Details of the modifications of carburetor construction, development of an electronic control and system optimation are supplied. Acceleration behaviour and mountain-climbing properties of the test vehicles was superior to serial motor-assisted bikes. Low-temperature test drives showed that start-up behaviour and the fluctuation of the systems around the preselected maximum speed was not yet fully satisfactory. Further solutions will be worked upon in a second development and test phase. (HWJ).

Class, E.; Wittlinger, U.

1989-01-01

322

Determination of gas temperature in the plasmatron channel according to the known distribution of electronic temperature  

Directory of Open Access Journals (Sweden)

Full Text Available An analytical method to calculate the temperature distribution of heavy particles in the channel of the plasma torch on the known distribution of the electronic temperature has been proposed. The results can be useful for a number of model calculations in determining the most effective conditions of gas blowing through the plasma torch with the purpose of heating the heavy component. This approach allows us to understand full details about the heating of cold gas, inpouring the plasma, and to estimate correctly the distribution of the gas temperature inside the channel.

Gerasimov Alexander V.

2013-01-01

323

On the gas temperature in circumstellar disks around A stars  

Science.gov (United States)

In circumstellar disks or shells it is often assumed that gas and dust temperatures are equal where the latter is determined by radiative equilibrium. This paper deals with the question whether this assumption is applicable for tenuous circumstellar disks around young A stars. In this paper the thin hydrostatic equilibrium models described by Kamp & Bertoldi (\\cite{Kamp}) are combined with a detailed heating/cooling balance for the gas. The most important heating and cooling processes are heating through infrared pumping, heating due to the drift velocity of dust grains, and fine structure and molecular line cooling. Throughout the whole disk gas and dust are not efficiently coupled by collisions and hence their temperatures are quite different. Most of the gas in the disk models considered here stays well below 300 K. In the temperature range below 300 K the gas chemistry is not much affected by Tgas and therefore the simplifying approximation Tgas = Tdust can be used for calculating the chemical structure of the disk. Nevertheless the gas temperature is important for the quantitative interpretation of observations, like fine structure and molecular lines.

Kamp, I.; van Zadelhoff, G.-J.

2001-07-01

324

High temperature gas-cooled reactors  

International Nuclear Information System (INIS)

The historical development in energy technology has the goal of realizing high temperatures and high efficiencies for the energy conversion processes. The high temperature reactor (HTR) realizes this goal in the best way compared to other reactor types; it uses ceramic materials and helium as the heat transfer media. The development of the fuel elements on the basis of coated particles is considered to be finished. Future applications are the production of electricity and the production of process heat for other areas of the energy market. Originally the thorium/uranium fuel cycle has been envisaged, today the low enriched uranium fuel cycle is of interest, because of the low prices of uranium. Typical for the HTR is its flexibility with respect to different concepts. On the basis of the existing prototypes AVR, THTR-300 and Forth St. Vrain the following two development lines are in discussion: reactors of small unit size and reactors of medium unit size. The safety qualities have been demonstrated by the operation of the AVR reactor in Juelich, which is now in operation for 19 years. These experiences will be of great importance for future plants. (author). 7 figs

1987-10-01

325

Gas temperature measurements using widely tunable long-wavelength VCSEL  

Science.gov (United States)

A method for gas temperature measurements with a widely tunable laser diode is presented. The method involves rapidly switching the laser frequency between two distantly spaced absorption lines chosen for optical thermometry. Direct absorption spectroscopy using a single-mode VCSEL was employed to probe the R10 and R22 lines of the 2?1+2?2 0+?3 combination band of CO2 near 6355.9 and 6363.7 cm-1 sequentially. A specially designed 0.5-m cryogenic gas cell was filled with 10 mbar CO2 at room temperature and cooled to 150 K with liquid N2. The VCSEL was modulated with a 10-kHz ramp superimposed on a 1-kHz square waveform to scan two 0.04 cm-1 intervals sequentially. The gas temperatures obtained with the VCSEL in the 150-300 K range are in a good agreement with those derived from gas pressure ratios. The maximum relative error of temperature measurements using the VCSEL was ± 3%. A compact VCSEL-based sensor can be developed for gas temperature and concentration measurements in the Martian atmosphere. The method proposed can be used for many applications including in situ monitoring of combustion processes.

Lytkine, A.; Lim, A.; Jäger, W.; Tulip, J.

2008-02-01

326

On The Gas Temperature of Molecular Cloud Cores  

CERN Document Server

We investigate the uncertainties affecting the temperature profiles of dense cores of interstellar clouds. In regions shielded from external ultraviolet radiation, the problem is reduced to the balance between cosmic ray heating, line cooling, and the coupling between gas and dust. We show that variations in the gas phase abundances, the grain size distribution, and the velocity field can each change the predicted core temperatures by one or two degrees. We emphasize the role of non-local radiative transfer effects that often are not taken into account, for example, when modelling the core chemistry. These include the radiative coupling between regions of different temperature and the enhanced line cooling near the cloud surface. The uncertainty of the temperature profiles does not necessarily translate to a significant error in the column density derived from observations. However, depletion processes are very temperature sensitive and a two degree difference can mean that a given molecule no longer traces t...

Juvela, M

2011-01-01

327

Pr:YAG temperature imaging in gas-phase flows  

Science.gov (United States)

In this study, a new thermographic phosphor for planar gas-phase thermometry is investigated. The thermographic phosphor used is composed of trivalent praseodymium (Pr3+) ions doped into a yttrium aluminum garnet (YAG) host. Spectrally-resolved emission data were taken in a furnace for temperatures up to 1,300 K. The emission spectra were used to develop a temperature measurement strategy utilizing a non-equilibrium population ratio. The developed temperature measurement technique was demonstrated in a turbulent heated air jet for exit temperatures ranging from 300 to 750 K. The results demonstrate the promise of the Pr:YAG phosphor for obtaining high-precision single-shot temperature measurements in gas-phase flows.

Jordan, Jonathan; Rothamer, David A.

2013-03-01

328

Titanium dioxide thin films for high temperature gas sensors  

International Nuclear Information System (INIS)

Titanium dioxide (TiO2) thin film gas sensors were fabricated via the sol-gel method from a starting solution of titanium isopropoxide dissolved in methoxyethanol. Spin coating was used to deposit the sol on electroded aluminum oxide (Al2O3) substrates forming a film 1 ?m thick. The influence of crystallization temperature and operating temperature on crystalline phase, grain size, electronic conduction activation energy, and gas sensing response toward carbon monoxide (CO) and methane (CH4) was studied. Pure anatase phase was found with crystallization temperatures up to 800 oC, however, rutile began to form by 900 oC. Grain size increased with increasing calcination temperature. Activation energy was dependent on crystallite size and phase. Sensing response toward CO and CH4 was dependent on both calcination and operating temperatures. Films crystallized at 650 oC and operated at 450 oC showed the best selectivity toward CO.

2010-10-29

329

High temperature gas dynamics an introduction for physicists and engineers  

CERN Multimedia

High Temperature Gas Dynamics is a primer for scientists, engineers, and students who would like to have a basic understanding of the physics and the behavior of high-temperature gases. It is a valuable tool for astrophysicists as well. The first chapters treat the basic principles of quantum and statistical mechanics and how to derive thermophysical properties from them. Special topics are included that are rarely found in other textbooks, such as the thermophysical and transport properties of multi-temperature gases and a novel method to compute radiative transfer. Furthermore, collision processes between different particles are discussed. Separate chapters deal with the production of high-temperature gases and with electrical emission in plasmas, as well as related diagnostic techniques.This new edition adds over 100 pages and includes the following updates: several sections on radiative properties of high temperature gases and various radiation models, a section on shocks in magneto-gas-dynamics, a sectio...

Bose, Tarit K

2014-01-01

330

Design and instrumentation of an automotive heat pump system using ambient air, engine coolant and exhaust gas as a heat source  

International Nuclear Information System (INIS)

Because the amount of waste heat used for comfort heating of the passenger compartment in motor vehicles decreases continuously as a result of the increasing engine efficiencies originating from recent developments in internal combustion engine technology, it is estimated that heat requirement of the passenger compartment in vehicles using future generation diesel engines will not be met by the waste heat taken from the engine coolant. The automotive heat pump (AHP) system can heat the passenger compartment individually, or it can support the present heating system of the vehicle. The AHP system can also be employed in electric vehicles, which do not have waste heat, as well as vehicles driven by a fuel cell. The authors of this paper observed that such an AHP system using ambient air as a heat source could not meet the heat requirement of the compartment when ambient temperature was extremely low. The reason is the decrease in the amount of heat taken from the ambient air as a result of low evaporating temperatures. Furthermore, the moisture condensed from air freezed on the evaporator surface, thus blocking the air flow through it. This problem can be solved by using the heat of engine coolant or exhaust gases. In this case, the AHP system can have a higher heating capacity and reuse waste heat. (author)

2009-01-01

331

High temperature water gas shift catalysts: a computer modelling study  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The high-temperature (HT) Water Gas Shift (WGS) reaction has considerable technological relevance for lowering CO content during the conversion of natural gas or liquid hydrocarbons to hydrogen. Conventional HT-WGS catalysts based on oxides of iron and chromium are well established industrially. However, it is crucial to remove any impurities present such as Cr6+, S or N during the catalytic process. In particular, Cr6+ is regarded as a Class I carcinogen and its presence is re...

Benny, S.

2010-01-01

332

Gravitational collapse of a magnetized fermion gas with finite temperature  

Energy Technology Data Exchange (ETDEWEB)

We examine the dynamics of a self-gravitating magnetized fermion gas at finite temperature near the collapsing singularity of a Bianchi-I spacetime. Considering a general set of appropriate and physically motivated initial conditions, we transform Einstein-Maxwell field equations into a complete and self-consistent dynamical system amenable for numerical work. The resulting numerical solutions reveal the gas collapsing into both, isotropic (''point-like'') and anisotropic (''cigar-like''), singularities, depending on the initial intensity of the magnetic field. We provide a thorough study of the near collapse behavior and interplay of all relevant state and kinematic variables: temperature, expansion scalar, shear scalar, magnetic field, magnetization, and energy density. A significant qualitative difference in the behavior of the gas emerges in the temperature range T/m{sub f} {proportional_to} 10{sup -6} and T/m{sub f} {proportional_to} 10{sup -3}. (orig.)

Delgado Gaspar, I. [Instituto de Geofisica y Astronomia (IGA), La Habana (Cuba); Perez Martinez, A. [Instituto de Cibernetica, Matematica y Fisica (ICIMAF), La Habana (Cuba); Sussman, Roberto A. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico (ICN-UNAM), Mexico (Mexico); Ulacia Rey, A. [Instituto de Cibernetica, Matematica y Fisica (ICIMAF), La Habana (Cuba); Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico (ICN-UNAM), Mexico (Mexico)

2013-07-15

333

High-temperature oxidation of graphite rods with temperature control by combustion gas recycle  

International Nuclear Information System (INIS)

The combustion of graphite (fuel blocks) is of fundamental importance in the fuel reprocessing scheme for the High-Temperature Gas-Cooled Reactor (HTGR). A study was made to evaluate a chunk-type burner for possible application in this reprocessing step. The combustion gases were recycled to allow operation at higher burn rates without an increase in graphite temperature. Graphite rods of two diameters were oxidized with makeup oxygen and recycled stack gases at various gas flow rates in an insulated reactor. Results of this study indicate a strong dependence of oxygen transfer on gas flow rate with little effect resulting from changes in graphite temperature. High carbon monoxide concentrations in the exit gas were not a problem except at oxygen concentrations below approx. 5%. Stable operation of a recycle controlled burner was achieved, avoiding the temperature excursions common in previous graphite burners

1980-01-01

334

High-temperature oxidation of graphite rods with temperature control by combustion gas recycle  

Energy Technology Data Exchange (ETDEWEB)

The combustion of graphite (fuel blocks) is of fundamental importance in the fuel reprocessing scheme for the High-Temperature Gas-Cooled Reactor (HTGR). A study was made to evaluate a chunk-type burner for possible application in this reprocessing step. The combustion gases were recycled to allow operation at higher burn rates without an increase in graphite temperature. Graphite rods of two diameters were oxidized with makeup oxygen and recycled stack gases at various gas flow rates in an insulated reactor. Results of this study indicate a strong dependence of oxygen transfer on gas flow rate with little effect resulting from changes in graphite temperature. High carbon monoxide concentrations in the exit gas were not a problem except at oxygen concentrations below approx. 5%. Stable operation of a recycle controlled burner was achieved, avoiding the temperature excursions common in previous graphite burners.

Canon, R.M.

1980-04-01

335

La catalyse d'épuration des gaz d'échappement automobiles. Situation actuelle et nouvelles orientations Catalytic Automotive Exhaust Gas Depollution. Present Status and New Trends  

Directory of Open Access Journals (Sweden)

Full Text Available Cet article passe en revue les différents systèmes catalytiques de post-traitement utilisés actuellement sur la plupart des automobiles pour limiter leurs rejets de polluants. Les systèmes sont différenciés par leur mode de fonctionnement, le type de moteur à dépolluer (deux-temps, quatre-temps, diesel ou essence ou par leur mode de réalisation. Les nouvelles orientations, prévues pour respecter les futures réglementations antipollution, sont également décrites. On montre que certains véhicules prototypes, équipés de moteurs à combustion interne, sont capables d'avoir des émissions très proches de zéro tout comme les véhicules électriques. A review is made of the various types of exhaust gas aftertreatment systems presently used on most vehicles to reduce pollutant emissions. The systems are differentiated by their mode of action, according to the engine type to be depolluted (two-stroke, four-stroke, diesel or spark-ignition, and by their type of make-up. The major developments foreseen in the future, in view of compliance with the new legislations, are described. It is shown that some prototype vehicles with internal combustion engines are able to emit pollutant quantities really close to zero, such as electric cars.

Prigent M.

2006-11-01

336

Exhaust gas aftertreatment system to meet EURO IV emission standards for diesel passenger cars; Abgasnachbehandlungssystem zur Erfuellung von EURO IV Grenzwerten bei PKW-Dieselmotoren  

Energy Technology Data Exchange (ETDEWEB)

To meet the European Emission Standard Step IV, an exhaust gas aftertreatment system will be necessary for Diesel engines. A system with a minimum NO{sub x} conversion rate of 65% will have the biggest chance to penetrate the complete vehicle spectrum like that as the 3-Way-Catalysts in gasoline engines. The urea-SCR based SINOx system, which is presented in this paper, meets these requirements. By means of optimization steps, e.g. cell density, chemical composition of the catalyst and the use of an additional oxidation catalyst, it is possible to reduce the necessary catalyst volume with the advantage that the system will fit into existing vehicles. (orig.) [Deutsch] Zur Erfuellung der zukuenftigen EURO IV Grenzwerte wird fuer den Dieselmotor ein effizientes Abgasnachbehandlungssystem erforderlich sein. Ein System, das mehr als 65% NO{sub x}-Konvertierungsrate erreicht, wird analog zum 3-Wege-Katalysator beim Ottomotor die groesste Chance haben, in der gesamten Fahrzeugpalette zum Einsatz zu kommen. Das in diesem Vortrag dargestellte SINOx-System, das auf der Harnstoff-SCR beruht, weist das dafuer erforderliche Reduktionspotential auf. Es wird gezeigt, dass durch entsprechende Optimierungsschritte, z.B. Zelldichte und chemische Zusammensetzung des Katalysators sowie Vorschalten eines Oxidationskatalysators, das gesamte katalytische Volumen auf eine Groesse reduziert werden kann, die fuer den Einbau bei bestehenden Fahrzeugen geeignet ist. (orig.)

Aust, M.; Tost, R.; Wissler, G. [Siemens AG Automobiltechnik (Germany); Fischer, S.; Zuerbig, J. [Siemens AG Kraftwerksunion (Germany)

1998-08-01

337

Laboratory fume hood and exhaust fan penthouse exposure risk analysis using the ANSI/ASHRAE 110-1995 and other tracer gas methods  

Energy Technology Data Exchange (ETDEWEB)

The use of the laboratory fume hood as the primary containment device in the laboratory has been a standard practice for almost half a century. Quantitative testing of the performance of these devices, however, is a more recent discipline. The use of the ANSI/ASHRAE 110-1995, Method of Testing Performance of Laboratory Fume Hoods (ASHRAE 1995) is becoming a standard specification in the purchase of new fume hoods, the commissioning of new laboratory facilities, and benchmarking fume hoods in existing facilities. Part 1 of this paper proposes a risk analysis method by which worker exposure to hazardous substances used in laboratory fume hoods may be estimated using results from the ASHRAE 110 method and formulae to extrapolate this information into potential exposure scenarios. Contaminated air leaking from hazardous exhaust systems located inside buildings or fan penthouses can pose a health risk to building occupants and maintenance workers. This is why prudent design practices for new buildings recommend that the fans powering these systems be located outside. In existing buildings with fans located inside or where a penthouse is required for weather conditions, however, it may be necessary to estimate potential worker exposure to hazardous agents released by these systems into the worker`s environment. Part 2 of this paper proposes a method and formulae by which this risk may be evaluated based on measurement of leakage using a tracer gas release, capture, and detection method.

Hitchings, D.T. [Hitchings Associates, Indianapolis, IN (United States)

1997-12-31

338

Quantitative planar laser-induced fluorescence imaging of multi-component fuel/air mixing in a firing gasoline-direct-injection engine: Effects of residual exhaust gas on quantitative PLIF  

Energy Technology Data Exchange (ETDEWEB)

A study of in-cylinder fuel-air mixing distributions in a firing gasoline-direct-injection engine is reported using planar laser-induced fluorescence (PLIF) imaging. A multi-component fuel synthesised from three pairs of components chosen to simulate light, medium and heavy fractions was seeded with one of three tracers, each chosen to co-evaporate with and thus follow one of the fractions, in order to account for differential volatility of such components in typical gasoline fuels. In order to make quantitative measurements of fuel-air ratio from PLIF images, initial calibration was by recording PLIF images of homogeneous fuel-air mixtures under similar conditions of in-cylinder temperature and pressure using a re-circulation loop and a motored engine. This calibration method was found to be affected by two significant factors. Firstly, calibration was affected by variation of signal collection efficiency arising from build-up of absorbing deposits on the windows during firing cycles, which are not present under motored conditions. Secondly, the effects of residual exhaust gas present in the firing engine were not accounted for using a calibration loop with a motored engine. In order to account for these factors a novel method of PLIF calibration is presented whereby 'bookend' calibration measurements for each tracer separately are performed under firing conditions, utilising injection into a large upstream heated plenum to promote the formation of homogeneous in-cylinder mixtures. These calibration datasets contain sufficient information to not only characterise the quantum efficiency of each tracer during a typical engine cycle, but also monitor imaging efficiency, and, importantly, account for the impact of exhaust gas residuals (EGR). By use of this method EGR is identified as a significant factor in quantitative PLIF for fuel mixing diagnostics in firing engines. The effects of cyclic variation in fuel concentration on burn rate are analysed for different fuel injection strategies. Finally, mixture distributions for late injection obtained using quantitative PLIF are compared to predictions of computational fluid dynamics calculations. (author)

Williams, Ben; Ewart, Paul [Department of Physics, Oxford University, Parks Road, Oxford OX1 3PU (United Kingdom); Wang, Xiaowei; Stone, Richard [Department of Engineering Science, Oxford University, Parks Road, Oxford OX1 3PJ (United Kingdom); Ma, Hongrui; Walmsley, Harold; Cracknell, Roger [Shell Global Solutions (UK), Shell Research Centre Thornton, P. O. Box 1, Chester, CH1 3SH (United Kingdom); Stevens, Robert; Richardson, David; Fu, Huiyu; Wallace, Stan [Jaguar Cars, Engineering Centre, Abbey Road, Whitley, Coventry, CV3 4LF (United Kingdom)

2010-10-15

339

The gas temperature in the surface layers of protoplanetary disks  

CERN Multimedia

Models for the structure of protoplanetary disks have so far been based on the assumption that the gas and the dust temperature are equal. The gas temperature, an essential ingredient in the equations of hydrostatic equilibrium of the disk, is then determined from a continuum radiative transfer calculation, in which the continuum opacity is provided by the dust. It has been long debated whether this assumption still holds in the surface layers of the disk, where the dust infrared emission features are produced. In this paper we compute the temperature of the gas in the surface layers of the disk in a self-consistent manner. The gas temperature is determined from a heating-cooling balance equation in which processes such as photoelectric heating, dissociative heating, dust-gas thermal heat exchange and line cooling are included. The abundances of the dominant cooling species such as CO, C, C+ and O are determined from a chemical network based on the atomic species H, He, C, O, S, Mg, Si, Fe (Kamp & Bertold...

Kamp, I

2004-01-01

340

Inlet turbine powered exhaust extractor for internal combustion engines  

Energy Technology Data Exchange (ETDEWEB)

A four-cycle internal combustion engine is provided with apparatus comprising a turbine in the inlet air flow path and an extracting compressor in the exhaust gas path. Where the internal combustion engine is an automobile engine and is operating under normal cruising conditions, the manifold inlet pressure is substantially less than atmospheric pressure and incoming air drives the inlet turbine to in turn drive the compressor. The arrangement is such that the inlet air is isentropically expanded while the exhaust gas back pressure is decreased. As a consequence, the energy of compression is reduced and the overall operating temperature of the internal combustion cycle is lowered with the result that more power is delivered for a given quantity of fuel.

Gertz, D.C.

1984-04-03

 
 
 
 
341

Ceramic membranes for gas separation at high temperatures. Final report  

Energy Technology Data Exchange (ETDEWEB)

Superior heat, wear, erosion, and corrosion resistance of ceramic materials have motivated the studies of processing-structure-performance interrelationships of ceramic membranes for high temperature gas separations. A literature review on pore transport mechanisms, physical structure of membranes, and module configuration of industrial membrane processes has been made to obtain a better understanding of membrane performance in gas separations. The research experience in decomposing polymer resins for ablative composites has stimulated a research interest in developing a dynamic model for membrane processes, incorporating a temperature effects on material and fluid properties. Brief summaries of the reviewed literature, permeability experiments, and process modeling are presented in this report.

Wang, C.J.

1994-03-01

342

Room-temperature gas sensors based on gallium nitride nanoparticles  

Science.gov (United States)

Room-temperature sensing characteristics for H 2, ethanol, NH 3, H 2S and water have been investigated with thick-film sensors based on GaN nanoparticles, prepared by a simple chemical route. In general, GaN nanoparticles exhibit satisfactory sensor properties for these gases and vapors even at room temperature. The sensitivity for ethanol is found to be highest, the sensitivity and recovery times being smallest. Gas sensor properties of GaN seem to be related to intrinsic defects, which act as sorption sites for the gas molecules.

Chitara, Basant; Late, Dattatray J.; Krupanidhi, S. B.; Rao, C. N. R.

2010-11-01

343

Gas sensor construction, particularly to determine oxygen content of combustion exhaust gases, particularly from internal combustion engines  

Energy Technology Data Exchange (ETDEWEB)

To facilitate manufacture of a sensor, particularly a polarographic sensor which has no sealing or heat expansion difficulties and only low heat capacity in the measuring range and electrical connections, a solid electrolyte is formed as a plate extending transversely across a bottom opening of a preferably ceramic tube, the plate having two electrodes applied to its major sides. The side facing the opening is covered with a ceramic layer having a predetermined diffusion or migration resistance to oxygen molecules. The electrical connections are formed by a conductive track extending on the inside of the ceramic tube, in contact with the sensing electrode on one side of the plate; and a counter head connected to a conductive bolt or pin and resiliently spring pressed against the electrode, and holding the plate and the diffusion barrier thereon in position in the sensor. The test gas is applied to the diffusion resistance layer through a ceramic heat storage plate, for instance, having openings therethrough, which has a film-type heater applied thereto, connected to a current source by conductive tracks positioned on the outside of the ceramic tube.

Beyer, B.; Dietz, H.; Friese, K.

1981-12-15

344

Chemical analysis and ozone formation potential of exhaust from dual-fuel (liquefied petroleum gas/gasoline) light duty vehicles  

Science.gov (United States)

Measures must be undertaken to lower the transport sector's contribution to anthropogenic emissions. Vehicles powered by liquefied petroleum gas (LPG) are an option due to their reduced emissions of air pollutants compared to engines with conventional fuels. In the present study, ten different dual-fuel LPG/gasoline light duty vehicles were tested, which all complied with European emission level legislation EURO-4. Tests with LPG and gasoline were performed on a chassis dynamometer by applying the New European Driving Cycle (NEDC) and emission factors and ozone formation potentials of both kinds of fuels were compared. The components investigated comprised regulated compounds, CO 2, volatile hydrocarbons and carbonyls. On-line analysis of aromatic species was carried out by resonance-enhanced multiphoton ionization-time-of-flight mass spectrometry (REMPI-TOFMS). We demonstrate that utilization of LPG can entail some environmental benefits by reducing emissions. However, for dual-fuel LPG/gasoline vehicles running on LPG the benefits are less than expected. The main reason is that dual-fuel vehicles usually start the engine up on gasoline even when LPG is selected as fuel. This cold-start phase is crucial for the quality of the emissions. Moreover, we demonstrate an influence on the chemical composition of emissions of vehicle performance, fuel and the evaporative emission system of the vehicles.

Adam, T. W.; Astorga, C.; Clairotte, M.; Duane, M.; Elsasser, M.; Krasenbrink, A.; Larsen, B. R.; Manfredi, U.; Martini, G.; Montero, L.; Sklorz, M.; Zimmermann, R.; Perujo, A.

2011-06-01

345

Gas temperature measurements in a microcathode sustained discharge in oxygen  

Science.gov (United States)

Microcathode sustained discharges (MCSD) produced between a microhollow cathode discharge (MHCD) and a third electrode offer the possibility to produce high density plasmas at low E/N values. Such discharges in oxygen could be attractive for efficient production of singlet O2 if the gas temperature remains low. The temperature of a discharge in oxygen at 50 Torr and for currents up to 2 mA and E/N of 25 Td was measured through a spectroscopic investigation of the plasma emission. The spatial distribution of the O2(b^1?) and O(5p) was measured. These species have a very different behaviour: O(5p) is mainly produced inside the hole of the 0.2 mm diameter MHCD and its density decreases by two orders of magnitude over a distance of 3 mm. On the other hand, the O2(b^1?) production by the MHCD is very low, and this state is mainly produced in the MCSD, with a smooth density gradient in the interelectrode gap. The gas temperature was determined in the MCSD from the high resolution spectra of the atmospheric band at 760 nm, while the gas temperature inside the hole of the MHCD was measured through the rotational spectra of the 337 nm 2^nd positive band of nitrogen, introduced at low concentration in the discharge. In our experimental conditions, the gas temperature in the MHCD is lower than 650 K and less than 400 K in the MCSD.

Puech, V.; Lagrange, J. F.; Sadeghi, N.; Touzeau, M.; Bauville, G.; Lacour, B.

2006-10-01

346

Exhaust gas emissions from various automotive fuels for light-duty vehicles. Effects on health, environment and energy utilization  

International Nuclear Information System (INIS)

The main aim of the investigation has been to assess the effects on health and environment from various alternative fuels for light-duty vehicles. Effects that can be identified and quantified, such as acidification, ozone formation, cancer risk and climate change, have been of primary interest but other effects, such as respiratory diseases, have also been investigated. Data have been collected through literature surveys for subsequent calculation of the mentioned effects in different time-frames. Corrections have been used to take into consideration the influence of climate, ageing and driving pattern. Emissions generated in fuel production have also been accounted for. The most significant and important differences between the fuels have been found for effects as ozone formation cancer risk and particulate emissions. Alternative fuels, such as methanol and methane (natural gas and biogas), significantly decrease the ozone formation in comparison to petrol, while ethanol, methanol and methane are advantageous concerning cancer risk. The particulate emissions are considerably higher for diesel engines fuelled by diesel oil and RME in comparison to the other fuels. In the future, the importance of acid emissions in the fuel production will increase since the NO_x and SO_x emissions will decrease from the vehicles. The emissions of climate gases could be significantly reduced by using non-fossil fuels but the efficiency of the drive train is also of importance. The technical development potential for further emission reductions is considerable for all fuels but the advantage for the best fuel options will remain in the future

1999-01-01

347

Engine test stand facilitating acoustic measurements on the exhaust side of engines  

Energy Technology Data Exchange (ETDEWEB)

The layout of a double 'hot/cold' engine test stand for tests on components and entire exhaust muffler systems is described in this article as it has been developed at the Lehrstuhl fuer Stroemungslehre, Universitaet Kaiserslautern, to expand the research potential available. The same pressure signals can be generated in the exhaust of a 'cold' engine as those in 'hot' internal-combustion engines of similar design by adding supercharging. That makes measurement of the signals easier. The elimination of the effects of load, temperature and varying exhaust gas composition allows a better numerical comparison and analysis of the measured values. Design changes on the exhaust system are then simpler to perform. More systematic measurements become feasible. The conception the engine test stand allows a number of test methods to be implemented which are not possible on 'hot' engine test stands of conventional design.

Berrsche, H.; Rosenberg, H.

1987-03-01

348

Transport of exhaust products in the near trail of a jet engine under atmospheric conditions  

Energy Technology Data Exchange (ETDEWEB)

The transport of exhaust effluents and the possibility of water ice contrail formation are investigated under the specific fluid dynamical conditions in the near exhaust trail of a subsonic jet aircraft at cruise altitude. By means of a computational model describing the two-dimensional turbulent mixing of a single jet of hot exhaust gas with the atmosphere, representative results are discussed on the temperature and saturation ratio evolutions of air parcels in the jet flow field as well as on radial distributions of exhaust effluents undergoing chemical reactions behind the nozzle exit with prescribed, typical net reaction rates. The results underline the importance of a simultaneous treatment of spatially resolved jet expansion together with microphysical and chemical processes, because this coupling leads to distinct concentration patterns for various classes of chemical reactants and is essential for the detailed prediction of contrails.

Karcher, B. [Universitat Muenchen, Freising (Germany)

1994-07-01

349

A highly efficient six-stroke internal combustion engine cycle with water injection for in-cylinder exhaust heat recovery  

Energy Technology Data Exchange (ETDEWEB)

A concept adding two strokes to the Otto or Diesel engine cycle to increase fuel efficiency is presented here. It can be thought of as a four-stroke Otto or Diesel cycle followed by a two-stroke heat recovery steam cycle. A partial exhaust event coupled with water injection adds an additional power stroke. Waste heat from two sources is effectively converted into usable work: engine coolant and exhaust gas. An ideal thermodynamics model of the exhaust gas compression, water injection and expansion was used to investigate this modification. By changing the exhaust valve closing timing during the exhaust stroke, the optimum amount of exhaust can be recompressed, maximizing the net mean effective pressure of the steam expansion stroke (MEP{sub steam}). The valve closing timing for maximum MEP{sub steam} is limited by either 1 bar or the dew point temperature of the expansion gas/moisture mixture when the exhaust valve opens. The range of MEP{sub steam} calculated for the geometry of a conventional gasoline engine and is from 0.75 to 2.5 bars. Typical combustion mean effective pressures (MEP{sub combustion}) of naturally aspirated gasoline engines are up to 10 bar, thus this concept has the potential to significantly increase the engine efficiency and fuel economy. (author)

Conklin, James C.; Szybist, James P. [Oak Ridge National Laboratory, 2360 Cherahala Blvd, Knoxville, TN 37932 (United States)

2010-04-15

350

A highly efficient six-stroke internal combustion engine cycle with water injection for in-cylinder exhaust heat recovery  

International Nuclear Information System (INIS)

A concept adding two strokes to the Otto or Diesel engine cycle to increase fuel efficiency is presented here. It can be thought of as a four-stroke Otto or Diesel cycle followed by a two-stroke heat recovery steam cycle. A partial exhaust event coupled with water injection adds an additional power stroke. Waste heat from two sources is effectively converted into usable work: engine coolant and exhaust gas. An ideal thermodynamics model of the exhaust gas compression, water injection and expansion was used to investigate this modification. By changing the exhaust valve closing timing during the exhaust stroke, the optimum amount of exhaust can be recompressed, maximizing the net mean effective pressure of the steam expansion stroke (MEPsteam). The valve closing timing for maximum MEPsteam is limited by either 1 bar or the dew point temperature of the expansion gas/moisture mixture when the exhaust valve opens. The range of MEPsteam calculated for the geometry of a conventional gasoline engine and is from 0.75 to 2.5 bars. Typical combustion mean effective pressures (MEPcombustion) of naturally aspirated gasoline engines are up to 10 bar, thus this concept has the potential to significantly increase the engine efficiency and fuel economy.

2010-04-01

351

Cogeneration application of the high temperature gas-cooled reactor  

International Nuclear Information System (INIS)

This paper describes the High Temperature Gas-Cooled Reactor (HTGR), unique among current nuclear technologoies in its ability to generate energy in temperature regimes previously limited to fossil fuels. It can offer commercial benefits in the production of electricity, and at the same time, expand the role of nuclear energy to the production of process heat. The system is ideally suited for cogeneration with central, baseloaaded industrial applications, such as petroleum refining, enhanced oil recovery and synfuels manufacture

1984-01-01

352

Air bubbles and temperature effect on blood gas analysis.  

Science.gov (United States)

The effect of temperature, time of storage, and presence of air bubbles in specimens for blood gas analysis was studied. The results show that air bubbles in a 10% proportion are undesirable because of significant elevation in the PO2, and the storage of anaerobic blood samples at room temperature (25 degrees C) is acceptable when measurements are done within the first 20 minutes. PMID:7430400

Madiedo, G; Sciacca, R; Hause, L

1980-09-01

353

Alternative high temperature gas piping systems for PFBC  

Energy Technology Data Exchange (ETDEWEB)

A literature/technical paper search to determine current/in-use design methods regarding high temperature piping systems, and material performance and development was completed. After review of the information, those manufacturers whose products were deemed potentially viable were contacted for further technical discussion and information gathering. This information was reviewed and candidate materials were selected. Investigation of the applicability of specific systems such as Mirror All Metal Reflective Insulation and Insulated Steam Injection Tubing were pursued with the manufacturer. ``Blue Sky`` discussions were held with G/C representatives of nuclear, fossil, and advanced technology systems engineering to identify design issues associated with the hot gas system and to investigate concepts and approaches to developing alternative designs. In order to develop an understanding of the design and operational issues associated with similar high temperature flue gas systems, G/C investigated the performance of the flue gas system at American Electric Power Corporation`s PFBC at the Tidd facility. The discussions included design, operation, performance, and modification history. The results of this investigation were that proven methods of protecting flue gas piping from the corrosive effect of acid and the erosive effects of gas stream particulate while providing, thermal insulating capabilities for operating temperatures at or above 1500{degrees}F are available.

Rubow, L.N.; Harvey, L.E.; Zalewski, J.T.; DeLallo, M.R.

1993-09-01

354

Low temperature dynamic characteristics of a three-way catalytic converter  

Energy Technology Data Exchange (ETDEWEB)

A mathematical model of a three-way catalytic converter based on a detailed chemical kinetic model has been created mainly to analyze the converter's dynamic behavior at low temperatures. The light-off process of the converter is analyzed in detail. Competition of species for empty noble metal surface determines the light-off characteristic, as inhibition processes increase light-off temperatures of some exhaust gas components in the complete exhaust mixture. Perturbations of the exhaust gas mixture around stoichiometry can in certain conditions decrease the effect of inhibition and lower the light-off temperature for some exhaust components. (author)

Balenovic, M.; Backx, A.C.P.M. [Eindhoven University of Technology (Netherlands). Dept. of Electrical Engineering; Harmsen, J.M.A.; Hoebink, J.H.B.J. [Eindhoven University of Technology (Netherlands). Laboratory of Chemical Reactor Engineering

2001-07-01

355

Low temperature dynamic characteristics of a three-way catalytic converter  

Energy Technology Data Exchange (ETDEWEB)

A mathematical model of a three-way catalytic converter based on a detailed chemical kinetic model has been created mainly to analyze the converter's dynamic behavior at low temperatures. The light-off process of the converter is analyzed in detail. Competition of species for empty noble metal surface determines the light-off characteristic, as inhibition processes increase light-off temperatures of some exhaust gas components in the complete exhaust mixture. Perturbations of the exhaust gas mixture around stoichiometry can in certain conditions decrease the effect of inhibition and lower the light-off temperature for some exhaust components. (orig.)

Balenovic, M.; Backx, A.C.P.M. [Technische Univ. Eindhoven (Netherlands). Dept. of Electrical Engineering; Harmsen, J.M.A.; Hoebink, J.H.B.J. [Technische Univ. Eindhoven (Netherlands). Lab. of Chemical Reactor Engineering

2001-07-01

356

Properties of oxide/oxide CMCs for high temperature applications in gas turbines  

Energy Technology Data Exchange (ETDEWEB)

Ceramic composites with continuous oxide fibres and an oxide matrix have potential for combining high damage tolerance (due to low brittleness compared to monolithic ceramics) with extreme temperature resistance. There are a lot of world-wide activities at laboratory level with Nextel{sup TM} type fibres. To prevent brittleness and increase fracture toughness, different material tailoring approaches based on a weak interface between the fibre and the matrix, and porous matrices are under development. Up to now, the limited thermal resistance of commercially available fibres and of the fibre/matrix interface restricts thermal stability. However, an increase of thermal stability up to more than 1200 C for 1000 hours lifetime is necessary for CMCs to represent valid substitutes of alloys, used so far in gas turbine applications. The target is to achieve 1200 C wall temperature by film cooling and convection without using a thermal barrier coating. Some prototypes, e.g. liners for gas turbine and exhaust tubes for aero-engines, have already been produced and successfully tested at moderately high temperature level. An oxide-based CMC material with Nextel{sup TM} 720 fibre and mullite matrix was developed for high temperature application in gas turbines. The composite laminate was characterised in terms of mechanical performance and thermal stability during and after high temperature exposure. Comparisons with a commercially available oxide/oxide material from COI are presented where data are available. Additionally, in order to explain the mechanical behaviour of the produced oxide/oxide composite, the Nextel{sup TM} 720 fibres were investigated in terms of high temperature behaviour in fibre bundle tests. The strong reduction of the Young's Modulus increasing temperature, as well as the unexpected reduction of the Weibull Modulus was monitored. The tested samples were subjected to different non-destructive evaluation (NDE) methods prior, during and after mechanical testing in order to assist interpretation of the obtained results and to identify characteristic damage mechanisms and their evolution during loading. (orig.)

Innocenti, M. [GE Oil and Gas - Nuovo Pignone S.p.A., Firenze (Italy); Puglia, P. del [GE Oil and Gas - Nuovo Pignone S.p.A., Firenze (Italy)]|[Univ. degli Studi di Firenze, Dipt. di Meccanica e Tecnologie Industriali (DMTI), Firenze (Italy); Pappas, Y.Z.; Dassios, C.G.; Steen, M. [JRC-Inst. for Energy, Petten (Netherlands); Kostopoulos, V.; Vlachos, D. [Univ. of Patras, Dept. of Mechanical Engineering and Aeronautics and ICE-HT/FORTH, Patras (Greece)

2002-07-01

357

The effects of strong temperature anisotropy on the kinetic structure of collisionless slow shocks and reconnection exhausts. Part I: PIC simulations  

CERN Document Server

A 2-D Riemann problem is designed to study the development and dynamics of the slow shocks that are thought to form at the boundaries of reconnection exhausts. Simulations are carried out for varying ratios of normal magnetic field to the transverse upstream magnetic field (i.e., propagation angle with respect to the upstream magnetic field). When the angle is sufficiently oblique, the simulations reveal a large firehose-sense (P_parallel>P_perpendicular) temperature anisotropy in the downstream region, accompanied by a transition from a coplanar slow shock to a non-coplanar rotational mode. In the downstream region the firehose stability parameter epsilon=1-mu_0(P_parallel-P_perpendicular)/ B^2 tends to lock in to 0.25. This balance arises from the competition between counterstreaming ions, which drives epsilon down, and the scattering due to ion inertial scale waves, which are driven unstable by the downstream rotational wave. At very oblique propagating angles, 2-D turbulence also develops in the downstrea...

Liu, Yi-Hsin; Swisdak, M

2011-01-01

358

Ideal gas of particle-like excitations at low temperatures  

International Nuclear Information System (INIS)

A phenomenological approach to the description of the equilibrium characteristics of ''kink'' gas is proposed, which is based on model of lattice gas. A general simple technique for obtaining the dynamical structure factors (DSF) of solitons and bions in the ''gas'' approximation is developed. The DSF defined by soliton excitations in the framework of the Klein-Gordon equation are obtained and discussed. It is shown that at low temperatures the bion type excitations dominate the contribution to the central peak (CP) as well as give rise to the satellites to appear at harmonics of the main bion frequency. Both the frequency of bions, ? and their average density are defined by the temperature of a system. A possibility is discussed to generalize the results to (2 + 1) and (3 + 1) dimensional models. (Auth.)

1983-01-01

359

Alkali removal from PFBC exhaust  

Energy Technology Data Exchange (ETDEWEB)

The objectives of this work are to reliably measure the alkali-vapor (Na and K) concentration in a pressurized fluidized-bed combustion (PFBC) exhaust and to demonstrate a fixed granular-bed sorber for the control of alkali vapors from the actual PFBC exhaust. During this reporting period, Test Series No. 8 with the PFBC/alkali sorber unit was conducted to demonstrate the AASB technique and to quantify the level of alkali vapors in the PFBC exhaust. In Test Series No. 8, Beulah lignite (North Dakota) was combusted with Tymochtee dolomite at average bed temperatures ranging from 850 to 875/degree/C and a system pressure of 9.2 atm absolute. Beulah lignite has a low potassium but a very high sodium content (0.024 and 0.67 wt %, respectively, on a moisture-free basis); therefore, our effort was concentrated on the vapor-phase sodium for this test. 2 refs.

Lee, S.H.D.; Carls, E.L.

1989-01-01

360

Fiscal 1998 achievement report on regional consortium research and development project. Venture business raising type consortium - Small business creation base type (Development of plasma-aided treatment system for exhaust gas from semiconductor process); 1998 nendo handotai process haiki gas no plasma shori system no kaihatsu seika hokokusho  

Energy Technology Data Exchange (ETDEWEB)

The results of studies conducted relative to the treatment of exhaust gas (toxic, dangerous, environment polluting) are stated. At the present time, every process of exhaust treatment is undertaken by the emitting plant, and the treatment ends with cleaning with scrubbers and disposal of sludge. This gives rise to problems about resource reuse, environmental conservation, and energy conservation. Such being the case, a system, in which a small but a highly efficient plasma generator coordinates with exhaust gas detoxification reaction, is developed and incorporated into each reaction unit. Exhaust gas (with its NOx diluted and then discharged into air at the current stage) is detoxified by plasma on the vacuum pump exhaust side. An atmospheric pressure plasma generation method best fit for CF{sub 4} decomposition and devices therefor, fixation of fluorine after decomposition, and methods for controlling the device are tested for verification. The torch discharge type is superior to the barrier discharge type and achieves a decomposition rate of 100% in a wet reaction chamber. In the wet discharge chamber, thanks to separation and solidification of fluorine from HF solution through neutralization by Ca and controlled pH, the fluorine concentration level in the drain at its final stage is reduced to 10ppm, or less, which is lower than the prescribed emission level of 15ppm. An ultrasonic gas component monitor is also developed. (NEDO)

NONE

2000-03-01

 
 
 
 
361

High temperature hydrogen sulfide adsorption on activated carbon. II. Effects of gas temperature, gas pressure and sorbent regeneration  

Energy Technology Data Exchange (ETDEWEB)

Several types of activated carbon sorbents were evaluated for removal of H{sub 2}S at high temperatures (400-600{degree}C) in an integrated gasification combined cycle (IGCC) power generation process. The effects of gas temperature, gas pressure and sorbent regeneration were examined. Adsorption experiments with zinc-impregnated activated carbon sample produced almost identical breakthrough times at varied temperatures (400-600{degree}C). High pressure (10 atm) adsorption experiments showed significantly longer breakthrough times at 10 atm compared to 1 atm. Gaseous H{sub 2} sample regeneration was found to be the most effective regeneration method of the variety of methods analyzed, with all previously H{sub 2}S adsorbed sulfur being removed in a H{sub 2} regeneration experiment. While additional research is necessary to evaluates further sample regeneration and multi-cycle adsorption/regeneration, results of temperature and pressure effect experiments are encouraging for IGCC applications.

Cal, M.P.; Strickler, B.W.; Lizzio, A.A.; Gangwal, S.K. [New Mexico Tech, Socorro, NM (USA). Dept. of Environmental Engineering

2000-07-01

362

Determining noncondensible gas fractions at elevated temperatures and pressures using wet and dry bulb temperature measurements  

Energy Technology Data Exchange (ETDEWEB)

The work reported in this note was undertaken to provide a method of determining the noncondensible gas fractions in a steam-gas mixture such as might be found in large reactor safety experiment like LOFT. In essence, the method used involves measuring the wet and dry bulb temperatures and using an algorithm, in place of the psychometric chart, to determine the partial pressure of the noncondensible gas in the mixture. In accomplishing this, the authors did the following: (1) extended the use of wet and dry-bulb temperature readings to determine mixture composition up to a temperature of 589 K and a pressure of 4.13 {times} 10{sup 6} Pa. (2) developed an algorithm to reduce the data (3) found which materials would survive those temperatures.

Griffith, P. (Massachusetts Inst. of Tech., Cambridge, MA (USA)); Bowman, J.

1987-02-01

363

Low temperature catalytic combustion of natural gas - hydrogen - air mixtures  

Energy Technology Data Exchange (ETDEWEB)

The low temperature catalytic combustion of natural gas - air mixtures would allow the development of no-NO{sub x} burners for heating and power applications. Using commercially available catalysts, the room temperature ignition of methane-propane-air mixtures has been shown in laboratory reactors with combustion efficiencies over 95% and maximum temperatures less than 700{sup o}C. After a 500 hour stability test, severe deactivation of both methane and propane oxidation functions was observed. In cooperation with industrial partners, scaleup to 3 kW is being investigated together with startup dynamics and catalyst stability. (author) 3 figs., 3 refs.

Newson, E.; Roth, F. von; Hottinger, P.; Truong, T.B. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

1999-08-01

364

High temperature alkali corrosion of ceramics in coal gas  

Energy Technology Data Exchange (ETDEWEB)

High temperature alkali corrosion has been known to cause premature failure of ceramic components used in advanced high temperature coal combustion systems such as coal gasification and clean-up, coal fired gas turbines, and high efficiency heat engines. The objective of this research is to systematically evaluate the alkali corrosion resistance of the most commonly used structural ceramics including silicon carbide, silicon nitride, cordierite, mullite, alumina, aluminum titanate, zirconia, and fireclay glass. The study consists of identification of the alkali reaction products (phase equilibria) and the kinetics of the alkali reactions as a function of temperature and time.

Pickrell, G.R.; Sun, T.; Brown, J.J.

1992-05-27

365

High temperature alkali corrosion of ceramics in coal gas  

Energy Technology Data Exchange (ETDEWEB)

High temperature alkali corrosion has been known to cause premature failure of ceramic components used in advanced high temperature coal combustion systems such as coal gasification and clean-up, coal fired gas turbines, and high efficiency heat engines. The objective of this research is to systematically evaluate the alkali corrosion resistance of the most commonly used structural ceramics including silicon carbide, silicon nitride, cordierite, mullite, alumina, aluminum titanate, zirconia, and fireclay glass. The study consists of identification of the alkali reaction products (phase equilibria) and the kinetics of the alkali reactions as a function of temperature and time.

Pickrell, G.R.; Sun, T.; Brown, J.J.

1992-08-29

366

High temperature alkali corrosion of ceramics in coal gas  

Energy Technology Data Exchange (ETDEWEB)

High temperature alkali corrosion has been known to cause premature failure of ceramic components used in advanced high temperature coal combustion systems such as coal gasification and clean-up, coal fired gas turbines, and high efficiency heat engines. The objective of this program is to systematically evaluate the alkali corrosion resistance of the most commonly used structural ceramics including silicon carbide, silicon nitride, cordierite, mullite, alumina, aluminum titanate, zirconia, and fireclay glass. The study consists of identification of the alkali reaction products (phase equilibria) and the kinetics of the alkali reactions as a function of temperature and time.

Pickrell, G.R.; Sun, T.; Brown, J.J.

1991-11-30

367

Thermal Creep Flow of Helium Gas at Cryogenic Temperatures  

Science.gov (United States)

We present a molecular dynamics (MD) simulation of nanoscale gas flow due to thermal creep at cryogenic temperatures. Helium is considered because its low liquefying temperature allows a wide range of cryogenic analysis. The thermal creep flow along a nanochannel is generated by applying temperature differences along the channel. Pressure and density variations are measured at various rarefaction conditions, covering the slip flow to the free molecular regimes. Thermo molecular pressure difference (TMPD) values are also calculated. Our results are compared with those in the literature.

Babac, G.; Reese, J. M.

2014-03-01

368

Simulation of fission gas release during temperature transients  

International Nuclear Information System (INIS)

Paper discusses the release of fission gases Xe and Kr as a diffusion process. It takes into account gas generation due to fission, gas precipitation in bubbles within the grains, diffusion of gas towards the grain boundaries, formation of grain boundary bubbles, its saturation and subsequent gas release, resolution of the gas contained into both types of bubbles and grain growth. Temperature profile calculations have allowed to evaluate the gas distribution in fuel pellet and in each grain. Analytical and numerical methods are used. Several experiments are simulated with the code and a good agreement between the measured Paper discusses the release of fission gases Xe and Kr as a diffusion process. It takes into and calculated results has been obtained. The influence of the initial grain size and density on fission gas release has been evaluated. It has been found that larger grain size and lower density both yield lower release, but density variation has a minor effect on the release. (author). 10 refs, 4 figs

1997-10-01

369

Intensity of gas dissolution in water below saturation temperature  

International Nuclear Information System (INIS)

To prevent from the formation of fire-damp mixture during water radiolysis in boiling nuclear reactors it is expedient to dissolve in the water explosion-proof hydrogen-helium mixture (96%) He) in the sections of natural circulation circuit prior to the core where the water temperature is below saturation temperature. The method is developed and formulas are given to determine the length of the gas dissolution section in the flow of underheated water. The method is based on dissolution model of single vapour-gas bubble in the flow of water not heated to saturation temperature. On the basis of the experiments conducted the required values of constant coefficients are found

1988-01-01

370

Reduction of exhaust gas emission of vehicles due to the use of alternative drive systems; Reduzierung der Emissionen durch Einsatz alternativer Antriebe beim Nutzfahrzeug  

Energy Technology Data Exchange (ETDEWEB)

The use of alternative drive systems makes it possible to increase the efficiency of vehicle drive systems and to reduce the emission of exhaust gases. Today, developments are focussing on hybrid drive concepts and on the use of alternative fuels. Hybrid city buses and distribution trucks as well as the use of alternative fuels highlight the potential for cutting the emission of exhaust gases. (orig.)

Hipp, E.; Lexen, G. [MAN Nutzfahrzeuge AG, Muenchen (Germany)

2007-07-01

371

A conceptual design for a combined cycle power plant comprising modified exhaust-heated gas turbine and a steam turbine plant. Part 2: Optimum solutions  

Energy Technology Data Exchange (ETDEWEB)

The author, to continue his design conception as well as the investigation into the application of the exhaust-heated gas turbine systems with multiple compression and expansion processes, has examined some possibilities for obtaining sufficiently large specific powers and high overall efficiencies. However, the analysis was carried out only in the aspect of application of such turbine systems for production of electric power in conjunction with steam turbine installations. The ratio of powers obtained, P{sub ST}/P{sub AT}, is about 1/4 in such systems, although some other possibilities were also investigated. For compression ratios within the range 6 to 35 the overall thermal efficiencies varied from 48 to about 35% (``First-law efficiency``) referred to the clutch, and specific powers approached approximately (380 + 90) kW per kilogram of working air per second, where 380 denotes the power from the air turbines, 90 -- the power from the steam turbines. Generally speaking, it has been found that the most advantageous systems are the power producing systems composed of 4C/4T, 4C/3T (or 3C/3T) because of their comparatively high overall thermal efficiencies, and IC/4T (or IC/3T) on account of their possible versatility in the application as combined/cogeneration plants. The symbols C and T denote, correspondingly, compressor, and turbine units, and the associated ciphers -- relevant numbers of compression and expansion processes. Actually more then one system, as an optimum, my be considered. It depends on what is more important in a given case: minimum fuel consumption (highest overall thermal efficiency), minimum air demand per one kWh (high specific power) or minimum cost of building such an installation (limited number of compressor and turbine units).

Golinski, J.A. [Technical Univ. of Wroclaw (Poland)

1994-12-31

372

The determination of regulated and some unregulated exhaust gas components from ethanol blended diesel fuels in comparison with neat diesel and ethanol fuel  

International Nuclear Information System (INIS)

Investigations that have been carried out at Luleaa University of Technology (LTU) show how exhaust gas emissions and engine performance are affected by the composition of the fuels. The fuels that have been tested and compared are two different ethanol blended diesel fuels, 'neat' diesel fuels and neat ethanol fuels. Two different, heavy-duty engines were used for the investigations; one for the neat ethanol fuels and the other for the ethanol blended diesel fuels and neat diesel fuels. The investigation also includes some tests with two oxidizing catalysts. Results from the investigation show that none of the fuels produce emissions exceeding the values of the 13-mode test (ECE R-49, 1997). Lowest HC-emission levels were found for the two 'neat' ethanol fuels although the difference between the HC-emissions can be considered negligible for the studied fuels. An effective reduction in the hydrocarbon emissions was achieved by using a catalyst. The investigation also shows that the NOx emissions were much lower for the neat ethanol fuels than for the other fuels. Even if the CO emissions from the two ethanol fuels were approximately three times higher than for the other investigated fuels the use of a catalyst equalize the CO emissions from the studied fuels. The formaldehyde and acetaldehyde emissions were clearly higher for the neat ethanol fuels than for the other investigated fuels. However, by using a catalyst the formaldehyde emission from the ethanol fuels could be decreased. Unfortunately, the use of a catalyst also resulted in an increase in the emission of acetaldehyde from the ethanol fuelled engine 10 refs, 11 figs, 5 tabs, 6 appendixes

1999-01-01

373

Vacuum exhaustion system for thermonuclear device  

International Nuclear Information System (INIS)

An ejector is disposed near a vacuum vessel and connected to the vacuum vessel by a short pipeline. The ejector is disposed at the inner side of a boundary of a high magnetic field area of a thermonuclear device. An argon gas is used as a driving gas for the ejector. If an argon gas is supplied to the ejector by an argon gas supply pipe, gases in the vacuum vessel and the pipeline are exhausted by the effect of the ejector. The pipeline of the exhaustion side of the ejector is connected to a gas recovery device. The gas recovering device comprises an argon trap having a heat exchanger therein. The gas recovering device is connected to an argon gas reutilizing circuit. The gas recovering device is connected to a backing pump system. The backing pump system is a mechanical type vacuum pump such as a turbo molecular pump. (I.N.)

1996-12-09

374

40 CFR 600.114-08 - Vehicle-specific 5-cycle fuel economy and carbon-related exhaust emission calculations.  

Science.gov (United States)

...false Vehicle-specific 5-cycle fuel economy and carbon-related exhaust emission...CONTINUED) ENERGY POLICY FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES Fuel Economy and Carbon-Related Exhaust...

2012-07-01

375

Catalytic removal of methane and NO{sub x} in lean-burn natural-gas engine exhaust; Elimination par catalyse du methane et des NO{sub x} dans les echappements de moteur au gaz naturel a basse combustion  

Energy Technology Data Exchange (ETDEWEB)

We have developed a new catalytic system to reduce the emissions of hydrocarbons, carbon monoxide (CO), and nitrogen oxides (NO{sub x}) contained in the exhaust gases from a lean-burn natural-gas engine. Catalytic oxidation of unburned hydrocarbons and CO in the exhaust has been studied for noble metals supported on alumina. (1) A low-loading catalyst comprising platinum supported on alumina (Pt/alumina) was efficient for the oxidation of CO and hydrocarbons without methane. The CO conversions were maintained at more than 98 % for 20,000 hours over the Pt/alumina. (2) A catalyst comprising platinum and palladium supported on alumina (Pt-Pd/alumina) exhibited higher levels of oxidation of hydrocarbons (including methane) than a catalyst comprising only palladium supported on alumina (Pd/alumina). Its oxidation also lasted longer. The combined effects of the platinum and palladium metals achieved high sulfur dioxide resistance. Increasing the palladium content in the Pt-Pd/alumina catalyst increased the level of oxidation and extended the lifetime of the catalyst. (3) A catalyst comprising silver supported on alumina (Ag/alumina) was effective at reducing the amount of NO{sub X} by using the unburned hydrocarbons in the exhaust gas. The NO{sub x} conversions over Ag/alumina were maintained at more than 30 % for 3,500 hours. We describe a total clean-up system consisting of a Ag/alumina catalyst and a Pt-Pd/alumina catalyst in series on the exhaust gas stream. (authors)

Yamamoto, H.; Satokawa, S.; Yahagi, M.; Yamaseki, K.; Hoshi, F.; Uchida, H.; Yokota, H. [Tokyo Gas Co., Ltd. (Japan)

2000-07-01

376

Technical assessment of gas turbine cycle for high temperature gas-cooled reactor  

International Nuclear Information System (INIS)

The gas turbine cycle appears to be the best near-term power conversion method for the high temperature gas-cooled reactor (HTGR). The author extensively investigates the gas turbine cycle including direct cycle, open indirect cycle and closed indirect cycle with medium of helium, nitrogen and air. Each cycle is analyzed and optimized from the thermodynamic standpoint and its turbo-machine is aerodynamically designed. As a result, the direct cycle with helium is an ideal option for the HTGR gas turbine cycle; however it is not easy to be realized based on current technology. The closed indirect cycle with helium or nitrogen is a practical one at present time, which can get the gas turbine cycle and lay technical bases for the future direct cycle

2003-04-01

377

Granular bed filtration of high temperature biomass gasification gas.  

Science.gov (United States)

High temperature cleaning of producer gas from biomass gasification has been investigated with a granular filter. Field tests were performed for several hours on a single filter element at about 550 degrees C. The results show cake filtration on the granular material and indicate good filtration of the biomass gasification producer gas. The relatively low pressure drop over the filter during filtration is comparable to those of bag filters. The granular filter can operate with high filtration velocities compared to bag filters and maintain high efficiency and a low residual pressure. This work is a part of the BioSOFC-up project that has a goal of utilizing the producer gas from the gasification plant in a solid oxide fuel cell (SOFC). The BioSOFC-up project will continue to the end of 2007. PMID:17337119

Stanghelle, Daniel; Slungaard, Torbjørn; Sønju, Otto K

2007-06-18

378

Gas diffusion and temperature dependence of bubble nucleation during irradiation  

DEFF Research Database (Denmark)

The continuous production of gases at relatively high rates under fusion irradiation conditions may enhance the nucleation of cavities. This can cause dimensional changes and could induce embrittlement arising from gas accumulation on grain boundaries. Computer calculations have been made of the diatomic nucleation of helium bubbles, assuming helium to diffuse substitutionally, with radiation-enhanced diffusion at lower temperatures. The calculated temperature dependence of the bubble density shows excellent agreement with that observed in 600 MeV proton irradiations, including a reduction in activation energy below Tm/2. The coalescence of diatomic nuclei due to Brownian motion markedly improves the agreement and also provides a well-defined terminal density. Bubble nucleation by this mechanism is sufficiently fast to inhibit any appreciable initial loss of gas to grain boundaries during the nucleation period, provided that incubation effects do not occur.

Foreman, A. J. E.; Singh, Bachu Narain

1986-01-01

379

High temperature gas cooled reactor steam-methane reformer design  

International Nuclear Information System (INIS)

The concept of the long distance transportation of process heat energy from a High Temperature Gas Cooled Reactor (HTGR) heat source, based on the steam-methane reforming reaction, is being evaluated by the Department of Energy as an energy source/application for use early in the 21st century. This paper summaries the design of a helium heated steam reformer utilized in conjunction with an intermediate loop, 850/degree/C reactor outlet temperature, HTGR process heat plant concept. This paper also discusses various design considerations leading to the mechanical design features, the thermochemical performance, the materials selection and the structural design analysis. 12 refs

1981-01-01

380

Chemical relaxation times in a hadron gas at finite temperature  

CERN Document Server

The relaxation times of particle numbers in hot hadronic matter with vanishing baryon number are estimated using the ideal gas approximation and taking into account resonance decays and annihilation processes as the only sources of particle number fluctuations. Near the QCD critical temperature the longest relaxation times turn out to be of the order of 10 fm and grow roughly exponentially to become of the order of $10^{3}$ fm at temperatures around 100 MeV. As a consequence of such long relaxation times, a clear departure from chemical equilibrium must be observed in the momentum distribution of secondary particles produced in high energy nuclear collisions.

Goity, J L

1993-01-01

 
 
 
 
381

Numerical modeling of exhaust smoke dispersion for a generic frigate and comparisons with experiments  

Science.gov (United States)

The exhaust smoke dispersion for a generic frigate is investigated numerically through the numerical solution of the governing fluid flow, energy, species and turbulence equations. The main objective of this work is to obtain the effects of the yaw angle, velocity ratio and buoyancy on the dispersion of the exhaust smoke. The numerical method is based on the fully conserved control-volume representation of the fully elliptic Navier-Stokes equations. Turbulence is modeled using a two-equation ( k- ?) model. The flow visualization tests using a 1/100 scale model of the frigate in the wind tunnel were also carried out to determine the exhaust plume path and to validate the computational results. The results show that down wash phenomena occurs for the yaw angles between ? =10° and 20°. The results with different exhaust gas temperatures show that the buoyancy effect increases with the increasing of the exhaust gas temperature. However, its effect on the plume rise is less significant in comparison with its momentum. A good agreement between the predictions and experiment results is obtained.

Ergin, Selma; Dobrucal?, Erinç

2014-06-01

382

Fuel for high temperature gas-cooled reactors  

International Nuclear Information System (INIS)

The fuel for high temperature gas-cooled reactors is composed of heat resistant materials such as carbon, graphite and ceramics without using metals, therefore, the safety is very high, high burnup is easily attained, and it is economically attractive in view of the utilization of thorium. The fuel is basically the minute fuel spheres of smaller than 1 mm diameter with four layers of carbon and carbide ceramic coatings. The coating layers are innermost buffer pyrolytic carbon (PyC) layer, high density PyC layer, SiC layer and outermost high density PyC layer. The buffer PyC layer protects the outer high density PyC layer from the damage due to nuclear fission recoil, and becomes the space for FP gas and CO gas. The other layers hold FP, and the SiC layer maintains the strength of a whole coated particle. A coated particle is formed into pellet, compact or ball shape by being mixed with graphite powder and phenol resin or pitch binder. The coated particle can hold FP inside even at 2000 deg C in a short time. The trend of development of the fuel for high temperature gas-cooled reactors in various countries, the behavior of the fuel, the improvement of the fuel and the disposal of spent fuel is reported. (K.I.)

1990-01-01

383

Fuel for high temperature gas-cooled reactors  

Energy Technology Data Exchange (ETDEWEB)

The fuel for high temperature gas-cooled reactors is composed of heat resistant materials such as carbon, graphite and ceramics without using metals, therefore, the safety is very high, high burnup is easily attained, and it is economically attractive in view of the utilization of thorium. The fuel is basically the minute fuel spheres of smaller than 1 mm diameter with four layers of carbon and carbide ceramic coatings. The coating layers are innermost buffer pyrolytic carbon (PyC) layer, high density PyC layer, SiC layer and outermost high density PyC layer. The buffer PyC layer protects the outer high density PyC layer from the damage due to nuclear fission recoil, and becomes the space for FP gas and CO gas. The other layers hold FP, and the SiC layer maintains the strength of a whole coated particle. A coated particle is formed into pellet, compact or ball shape by being mixed with graphite powder and phenol resin or pitch binder. The coated particle can hold FP inside even at 2000 deg C in a short time. The trend of development of the fuel for high temperature gas-cooled reactors in various countries, the behavior of the fuel, the improvement of the fuel and the disposal of spent fuel is reported. (K.I.).

Fukuda, Kousaku (Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment)

1990-04-01

384

Passive Acoustic Tomography Tested for Measuring Gas Temperatures  

Science.gov (United States)

The requirements of higher performance, better fuel economy, and lower emissions place an increasing premium on knowing the internal operating parameters of jet engines. One of the most important is the gas temperature in the post combustor section of the engine. Typically the gas temperature is measured with a thermocouple probe or by some optical technique such as Rayleigh scattering. Probes, while providing valuable information, have several limitations. The probe signal must be corrected for radiation and conduction losses, probes provide only a point measurement, and probes must be constructed of materials whose melting points are lower than the temperature of the environment into which they are inserted. Some of the disadvantages of probes are overcome by various optical techniques. Nothing needs to be inserted into the flow, and the temperature can be directly related to the signal by known physical laws. However, optical techniques require optical access (i.e., a window) and a light source (such as a laser), and they are very sensitive to the presence of particles in the flow. To overcome these problems, researchers from the NASA Glenn Research Center and The University of Nevada are developing a technique that uses sound instead of light to measure gas temperature. Like optical techniques, it is nonintrusive--no probe need be exposed to the combustion environment--and the temperature is directly related to a measured quantity--the speed of sound, which is proportional to the square root of the absolute temperature. The temperature profile inside the engine is constructed from the differences in arrival time between correlated signals from an array of microphones placed around the circumference of the engine. In much the same way as a complete picture of the inside of your body can be constructed from an array of x-ray photographs taken at different angles, the temperature profile in the engine is constructed from the angular array of microphones. It is tomography by sound waves. Active acoustic tomography, in which a sound pulse is injected into the flow and the time delays between members of an array of microphones are used to construct the temperature field has been used successfully in the stacks of power plants. However, the flow field inside a jet engine is much too noisy for it to be possible to detect an externally injected sound pulse. Instead we are developing passive acoustic tomography, which uses the sound already present in the flow.

Fralick, Gustave C.; Kleppe, John

2004-01-01

385

Gearbox Scheme in High Temperature Reactor Helium Gas Turbine System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Helium Turbine is used in High Temperature Reactor Helium Gas Turbine (HTR-GT) system, by which the direct helium circulation between the reactor and turbine generator system will come true. Between helium turbine and generator, there is gearbox device which reduces the turbine rotation speed to normal speed required by the generator. Three optional gearbox schemes are discussed. The first is single reduction cylindrical gearbox, which consists of one high speed gear and one low speed gear. I...

2012-01-01

386

Development of high temperature coal gas desulfurization systems -- An overview  

Energy Technology Data Exchange (ETDEWEB)

Integrated Gasification Combined-Cycle (IGCC) processes are among the leading contenders for generation of electricity from coal in the 21st century. Coal gas desulfurization to sufficiently low levels at temperatures above 350 C is now recognized as crucial to efficient and economical utilization of coal in advanced IGCC processes. The implementation of hot coal gas desulfurization heavily relies on the development of regenerable sorbent materials that can efficiently remove H{sub 2}S (from several thousand ppmv levels down to a few ppmv) over a very large number of sulfidation/regeneration cycles. Over the last two decades, development of high temperature desulfurization sorbents has been focused on using various combinations of transition metal oxides as regenerable sorbents. The selection of suitable metal oxides is generally based on a number of requirements imposed by the IGCC process, which include favorable thermodynamic equilibria during sulfidation and regeneration, relatively high sulfidation and regeneration reactivities, good mechanical strength and structural stability, and environmental friendliness, all at a reasonably low cost. The desulfurization reactor can have a fixed-bed, a moving-bed, a transport reactor, or a bubbling fluidized-bed reactor design. Depending on process conditions and the application intended, each of these reactor configurations offers advantages, but also has limitations. The parameters guiding the choice of a reactor system include reactivity of the sorbent, crush strength and/or attrition resistance of the sorbent, absorption capacity of the sorbent, temperature distribution inside the reactors, and SO{sub 2} concentration in the regeneration product gas. This paper provides an overview of high temperature fuel gas desulfurization within the context of IGCC processes. The paper focuses on the studies related to the development of regenerable sorbents and addresses thermodynamic considerations, sulfidation kinetics, regenerability, and long term durability of a number of novel sorbents. A general comparison of different reactor configurations is provided and their implications in the context of the IGCC process are also discussed.

Abbasian, J.; Slimane, R.B.; Lau, F.S.; Wangergow, J.R.; Zarnegar, M.K. [Inst. of Gas Technology, Des Plaines, IL (United States)

1997-12-31

387

Experimental study of gas turbine combustion with elevated fuel temperatures  

Science.gov (United States)

Many thermal management challenges have developed as advancements in gas turbine engine designs are made. As the thermal demands on gas turbine engines continue to increase, the heat sink available in the combustor fuel flow becomes more attractive. Increasing the temperature of fuel by using it as a heat sink can lead to higher combustion efficiency due to the increase in flow enthalpy and improved vaporization of the heated fuel. Emissions levels can also be affected by using heated fuels with the levels of carbon monoxide and unburned hydrocarbons tending to decrease while the amount of the oxides of nitrogen tends to increase. Although there are several benefits associated with using heated fuels in gas turbine engines, some problems can arise from their use including combustion instabilities, flashing within the fuel injector, and fuel coking or deposit formation within the fuel system. Various deoxygenation methods have been created to address the coking problem seen when using heated fuels. In the Gas Turbine Test Cell of the High Pressure Laboratory at Purdue University's Maurice J. Zucrow Laboratories, a 5 MW combustion rig was developed to complete combustion test with heated fuels. The facility's supply systems including heated air, jet fuel, cooling water, and nitrogen were designed and integrated to produce simulated engine conditions within the combustion rig. Heating capabilities produced fuel temperatures ranging up to 600 deg F. Testing was completed with two fuel deoxygenation methods: nitrogen sparging and catalytic deoxygenation. Results from the testing campaign included conventional pressure, temperature, and fuel property measurements; however, the most important measurements were the emissions samples that were analyzed for each test condition. Levels of carbon monoxide, unburned hydrocarbons, and oxides of nitrogen were determined as well as the combustion efficiency calculated from these emissions measurements. The trends in emissions and performance from the increase in fuel temperature will be discussed. In addition, high frequency pressure data were recorded during testing to monitor combustion instabilities. Fuel samples were also taken and analyzed to document the changes in the volatile composition of the fuel from the two deoxygenation methods. The testing campaign was extremely successful. All project objectives were met with the heated fuel testing campaign. The combustion rig was run safely with fuel temperature up to 600 deg F, allowing the effects of elevated fuel temperatures on the performance and emissions of a gas turbine combustor to be evaluated as planned.

Wiest, Heather K.

388

Integration of a molten carbonate fuel cell with a direct exhaust absorption chiller  

Energy Technology Data Exchange (ETDEWEB)

A high market value exists for an integrated high-temperature fuel cell-absorption chiller product throughout the world. While high-temperature, molten carbonate fuel cells are being commercially deployed with combined heat and power (CHP) and absorption chillers are being commercially deployed with heat engines, the energy efficiency and environmental attributes of an integrated high-temperature fuel cell-absorption chiller product are singularly attractive for the emerging distributed generation (DG) combined cooling, heating, and power (CCHP) market. This study addresses the potential of cooling production by recovering and porting the thermal energy from the exhaust gas of a high-temperature fuel cell (HTFC) to a thermally activated absorption chiller. To assess the practical opportunity of serving an early DG-CCHP market, a commercially available direct fired double-effect absorption chiller is selected that closely matches the exhaust flow and temperature of a commercially available HTFC. Both components are individually modeled, and the models are then coupled to evaluate the potential of a DG-CCHP system. Simulation results show that a commercial molten carbonate fuel cell generating 300 kW of electricity can be effectively coupled with a commercial 40 refrigeration ton (RT) absorption chiller. While the match between the two ''off the shelf'' units is close and the simulation results are encouraging, the match is not ideal. In particular, the fuel cell exhaust gas temperature is higher than the inlet temperature specified for the chiller and the exhaust flow rate is not sufficient to achieve the potential heat recovery within the chiller heat exchanger. To address these challenges, the study evaluates two strategies: (1) blending the fuel cell exhaust gas with ambient air, and (2) mixing the fuel cell exhaust gases with a fraction of the chiller exhaust gas. Both cases are shown to be viable and result in a temperature drop and flow rate increase of the gases before the chiller inlet. The results show that no risk of cold end corrosion within the chiller heat exchanger exists. In addition, crystallization is not an issue during system operation. Accounting for the electricity and the cooling produced and disregarding the remaining thermal energy, the second strategy is preferred and yields an overall estimated efficiency of 71.7%. (author)

Margalef, Pere; Samuelsen, Scott [National Fuel Cell Research Center (NFCRC), University of California, Irvine, CA 92697-3550 (United States)

2010-09-01

389

Changes of microstructures and high temperature properties during high temperature service of Niobium added ferritic stainless steels  

International Nuclear Information System (INIS)

To improve the fuel economy and clean the exhaust gas of automobiles, the temperature of exhaust gas is getting higher and higher. Niobium added ferritic stainless steels are often being used in automotive exhaust systems, because of their excellent heat resistant properties, especially thermal fatigue resistance, which is very important for materials of exhaust manifold. However, coarse precipitates containing niobium, which cause degradation in high temperature strength and thermal fatigue resistance, are unavoidable during high temperature service. In this study, changes of microstructures and high temperature properties in high temperature aging were investigated using several Nb added ferritic stainless steels. It has been found that the microstructure stability of Nb-Ti-Mo alloyed steels in high temperature aging is superior to that of Nb added steels. The microstructure stability leads to less degradation in high temperature strength during high temperature aging and to longer thermal fatigue lives of Nb-Ti-Mo alloyed steels than in Nb added steels

2003-06-25

390

Exhaust makes electricity. Eksos blir elektrisitet  

Energy Technology Data Exchange (ETDEWEB)

The article deals briefly with a prototype process, developed in Norway, for improving the efficiency of oil- or gas-fired power plants on offshore platforms. The carbon dioxide reducing process, dubbed ABC (Air Bottom Cycle), converts the exhaust gas heat from the turbines to electricity. The fuel consumption is to be reduced by about 30%. 1 fig.

Kjaervik, A.

1994-06-01

391

Vacuum exhaustion system for thermonuclear device  

International Nuclear Information System (INIS)

The present invention provides an efficient, economical and safe large-volumed gas exhaustion system for a large sized thermonuclear device. Namely, a cryopump is connected to the downstream end of a gas exhaustion channel for a vacuum chamber. Opening degree controllable first and second valve plates are disposed to an intermediate portion of the gas exhaustion channel. A conductance control valve having an intermediate chamber between the first and the second valve plates is disposed. A first screw-groove vacuum pump is connected to the gas exhaustion channel at the upstream of the first valve plate, a second screw-groove vacuum pump is connected to the intermediate chamber and a third screw-groove vacuum pump is connected to the downstream of the second valve plate respectively. With such a constitution, since the cryopump is combined with the first, second, third screw-groove vacuum pumps and the conductance control valve, the operation can be conducted under operation conditions suitable to the cryopumps and screw-groove vacuum pumps with good efficiency. Since the screw-groove vacuum pumps which have a simpler constitution than a turbo molecular pump and can be easily increased in the size, gas exhaustion system of large capacity tends to be constructed. (I.S.)

1995-05-24

392

Vacuum exhaustion system for thermonuclear device  

Energy Technology Data Exchange (ETDEWEB)

The present invention provides an efficient, economical and safe large-volumed gas exhaustion system for a large sized thermonuclear device. Namely, a cryopump is connected to the downstream end of a gas exhaustion channel for a vacuum chamber. Opening degree controllable first and second valve plates are disposed to an intermediate portion of the gas exhaustion channel. A conductance control valve having an intermediate chamber between the first and the second valve plates is disposed. A first screw-groove vacuum pump is connected to the gas exhaustion channel at the upstream of the first valve plate, a second screw-groove vacuum pump is connected to the intermediate chamber and a third screw-groove vacuum pump is connected to the downstream of the second valve plate respectively. With such a constitution, since the cryopump is combined with the first, second, third screw-groove vacuum pumps and the conductance control valve, the operation can be conducted under operation conditions suitable to the cryopumps and screw-groove vacuum pumps with good efficiency. Since the screw-groove vacuum pumps which have a simpler constitution than a turbo molecular pump and can be easily increased in the size, gas exhaustion system of large capacity tends to be constructed. (I.S.)

Hiroki, Seiji; Abe, Tetsuya; Murakami, Yoshio; Nakamura, Jun-ichi [Japan Atomic Energy Research Inst., Tokyo (Japan); Iguchi, Masashi

1996-12-03

393

Prediction of temperature front in a gas turbine combustion chamber  

Energy Technology Data Exchange (ETDEWEB)

Numerical computation has been applied to investigate the temperature field in a gas turbine combustion chamber. The simulation assumed that pressure imbalance conditions of air flow between primary and secondary inlets occur. The combustion chamber under study is part of a 70 MW gas turbine from an operating combined cycle power plant. The combustion was simulated with normal fuel-air flow rate assuming stoichiometric conditions. Under these conditions characteristic temperature and pressure fields were obtained provided equity of boundary conditions at air inlets applies. However, with pressure distribution imbalances of the order of 3 kPa between primary and secondary air inlets, excessive heating in regions other than the combustion chamber core were obtained. Over heating in these regions helped to explain what was observed to produce permanent damage to auxiliary equipment surrounding the combustion chamber core, like the cross flame pipes. It is observed that high temperatures which normally develop in the central region of the combustion chamber may reach other surrounding upstream regions by modifying slightly the air pressure. Microscope scanning of the damaged pipes confirmed that the material was exposed to high temperatures such as predicted through the numerical computation. (Author)

Sierra, F.Z.; Kubiak, J.; Gonzalez, G.; Urquiza, G. [Universidad Autonoma del Estado de Morelos, Centro de Investigacion en Ingenieria y Ciencias Aplicadas, Cuernavaca, Morelos (Mexico)

2005-06-01

394

Temperature Effects in a Fermi Gas with Population Imbalance  

CERN Document Server

We investigate temperature effects in a Fermi gas with imbalanced spin populations. From the general expression of the thermal gap equation we find, in {\\it weak coupling limit}, an analytical expression for the transition temperature $T_c$ as a function of various possibilities of chemical potential and mass asymmetries between the two particle species. For a range of asymmetry between certain specific values, this equation always has two solutions for $T_c$ which has been interpreted as a reentrant phenomena or a pairing induced by temperature effect. We show that the lower $T_c$ is never related to a stable solution. The same results are obtained in {\\it strong coupling limit}. The thermodynamical potential is carefully analyzed to avoid the consideration of the unstable solutions.

Caldas, Heron

2008-01-01

395

Design of indirect gas turbine cycle for a modular high temperature gas cooled reactor  

International Nuclear Information System (INIS)

This paper describes a design of the indirect gas turbine cycle for the 200MWt pebble bed MHTGR. In the design, the helium out of the Intermediate Heat eXchanger (IHX) is extracted to a small RPV cooling system. The gas flows through a small RPV recuperator and is cooled down, then it is used to cool the RPV. The whole primary circuit is integrated in a pressure vessel. The core inlet/outlet temperatures are 550 deg. C/900 deg. C, which can supply a gas heat source of 500 deg. C/850 deg. C in the secondary side. The heat source could be used to drive a nitrogen gas turbine cycle and a plant busbar electricity generation efficiency of about 48% is estimated. The thermodynamic calculation, preliminary design of the system components, and the important accident analysis are described in this paper. (author). 5 refs, 3 figs, 4 tabs

1996-08-01

396

Optimum Reactor Outlet Temperatures for High Temperature Gas-Cooled Reactors Integrated with Industrial Processes  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the results of a temperature sensitivity study conducted to identify the optimum reactor operating temperatures for producing the heat and hydrogen required for industrial processes associated with the proposed new high temperature gas-cooled reactor. This study assumed that primary steam outputs of the reactor were delivered at 17 MPa and 540°C and the helium coolant was delivered at 7 MPa at 625–925°C. The secondary outputs of were electricity and hydrogen. For the power generation analysis, it was assumed that the power cycle efficiency was 66% of the maximum theoretical efficiency of the Carnot thermodynamic cycle. Hydrogen was generated via the hightemperature steam electrolysis or the steam methane reforming process. The study indicates that optimum or a range of reactor outlet temperatures could be identified to further refine the process evaluations that were developed for high temperature gas-cooled reactor-integrated production of synthetic transportation fuels, ammonia, and ammonia derivatives, oil from unconventional sources, and substitute natural gas from coal.

Lee O. Nelson

2011-04-01

397

Challenges on the way to noble gas temperatures on speleothems  

Science.gov (United States)

In the last years, speleothems gained importance as a paleoclimate archive. Nonetheless, so far no proxy in speleothems has really gained acceptance as a commonly used paleotemperature indicato