AN IMPROVED SLOW-COMBUSTION GAS PIPETTE

1932 ◽  
Vol 7 (6) ◽  
pp. 680-681 ◽  
Author(s):  
C. H. Bayley
Keyword(s):  
Complete Combustion ◽  
Combustion Gas ◽  
Combustible Gas ◽  
Slow Combustion ◽  
New Type

A new type of slow-combustion gas pipette is described in which the combustible gas is admitted through a platinum jet and impinges directly on to the platinum spiral, thereby ensuring complete combustion and eliminating the danger of explosion.

scholarly journals Effect of Pressure on Second-Generation Pressurized Fluidized Bed Combustion Plants

1994 ◽  
Vol 116 (2) ◽  
pp. 345-351 ◽  
Author(s):  
A. Robertson ◽  
D. Bonk
Keyword(s):  
Gas Turbine ◽  
Fluidized Bed ◽  
Coal Gasification ◽  
Second Generation ◽  
Electrical Power ◽  
Fluidized Bed Combustion ◽  
Fuel Gas ◽  
Combustion Gas ◽  
New Type ◽  
Pressurized Fluidized Bed Combustion

In the search for a more efficient, less costly, and more environmentally responsible method for generating electrical power from coal, research and development has turned to advanced pressurized fluidized bed combustion (PFBC) and coal gasification technologies. A logical extension of this work is the second-generation PFBC plant, which incorporates key components of each of these technologies. In this new type of plant, coal is devolatilized/carbonized before it is injected into the PFB combustor bed, and the low-Btu fuel gas produced by this process is burned in a gas turbine topping combustor. By integrating coal carbonization with PFB coal/char combustion, gas turbine inlet temperatures higher than 1149°C (2100°F) can be achieved. The carbonizer, PFB combustor, and particulate-capturing hot gas cleanup systems operate at 871°C (1600°F), permitting sulfur capture by time-based sorbents and minimizing the release of coal contaminants to the gases. This paper presents the performance and economics of this new type of plant and provides a brief overview of the pilot plant test programs being conducted to support its development.

COMBUSTION ENERGY AND FOSSIL (NON-BIOBASED) CO2 EMISSIONS FROM RUBBER COMPOUNDS UNDER COMPLETE COMBUSTION BY BOMB CALORIMETER BASED ON ISO 20463 METHODS

2020 ◽  
pp. 000-000
Author(s):  
Masao Kunioka ◽  
Akira Saito ◽  
Mari Nakajima ◽  
Shunji Araki
Keyword(s):  
Carbon Content ◽  
Co2 Emissions ◽  
Co2 Emission ◽  
Calorific Value ◽  
Co2 Concentration ◽  
Complete Combustion ◽  
Combustion Gas ◽  
Combustion Energy ◽  
Bomb Calorimeter ◽  
Rubber Compounds

ABSTRACT Combustion energy (gross calorific value) and total CO2 emissions from 11 model rubber compounds, polyurethane, and other materials related to rubber products during a one-time complete combustion were measured sequentially using methods in accordance with ISO 20463 using a bomb calorimeter. Eleven model rubber compounds and biobased polyurethane were prepared for these measurements. The combustion energies of the model rubber compounds were found to be 27 900 to 40 700 J/g. These measured combustion energies, after subtraction of the combustion energy of carbon black (CBK), were related linearly to the carbon content of these samples without CBK. A difference in the combustion energy of rubber products and that of CBK was observed. From these results, an estimation via the calculation of the combustion energy of the rubber products was developed from the formulation of the rubber product. Total CO2 emissions could be calculated by the results of total volume and the CO2 concentration of combustion gas collected from a bomb used for the measurement of combustion energies. The total CO2 emissions of these samples were 1.83 to 3.02 g/g. The relationship between total CO2 emission from model rubber compounds and the theoretical CO2 emission calculated from the carbon content of these samples was linear. It was found that these methods had high precision. High reproducibility of the methods for such measurement was confirmed by the use of a round-robin test, which was carried out by six Japanese chemical laboratories.

scholarly journals Effect of Pressure on Second-Generation Pressurized Fluidized Bed Combustion Plants

1993 ◽  
Author(s):  
Archie Robertson ◽  
Donald Bonk
Keyword(s):  
Gas Turbine ◽  
Fluidized Bed ◽  
Coal Gasification ◽  
Second Generation ◽  
Electrical Power ◽  
Fluidized Bed Combustion ◽  
Fuel Gas ◽  
Combustion Gas ◽  
New Type ◽  
Pressurized Fluidized Bed Combustion

In the search for a more efficient, less costly, and more environmentally responsible method for generating electrical power from coal, research and development has turned to advanced pressurized fluidized bed combustion (PFBC) and coal gasification technologies. A logical extension of this work is the second-generation PFBC plant, which incorporates key components of each of these technologies. In this new type of plant, coal is devolatilized/carbonized before it is injected into the PFB combustor bed, and the low-Btu fuel gas produced by this process is burned in a gas turbine topping combustor. By integrating coal carbonization with PFB coal/char combustion, gas turbine inlet temperatures higher than 1149°C (2100°F) can be achieved. The carbonizer, PFB combustor, and particulate-capturing hot gas cleanup systems operate at 871°C (1600°F), permitting sulfur capture by lime-based sorbents and minimizing the release of coal contaminants to the gases. This paper presents the performance and economics of this new type of plant and provides a brief overview of the pilot plant test programs being conducted to support its development.

How Is a Correct GT Combustor Heat Balance Established?

2020 ◽  
Author(s):  
Hans E. Wettstein
Keyword(s):  
Ambient Temperature ◽  
Specific Heat ◽  
Gas Turbine ◽  
Flow Rate ◽  
Heat Balance ◽  
Specific Enthalpy ◽  
Complete Combustion ◽  
Heating Value ◽  
Combustion Gas ◽  
The Heat Balance

Abstract The heat balance of gas turbine (GT) combustors is used for determining the average Combustor Exit Temperature (CET). It is important for designing the hot parts in this area. Sensor measurements of the CET are nearly impossible due to its high level up to above 1700°C. Therefore it is typically evaluated based on a 1-D cycle calculation, in which the combustor receives compressed air and fuel and it discharges the hot combustion gas at the temperature CET. In the classic approach the fuel heat received in the combustor is evaluated based on the lower heating value (LHV) of the fuel and after the complete combustion the mixture of excess air and combustion products leaves the combustor at the temperature CET, which is calculated based on its specific enthalpy function. So far so simple but this is tricky. The reaction energy is not the LHV but the higher heating value HHV, which includes additionally the discharged energy for condensing the combustion water at ambient temperature. The total heat comes into the flue-gas in the combustor, which is designed for a combustion efficiency of typically 99%+. There is no significant downstream reaction known, which could add the missing difference of HHV-LHV. In GT based power stations condensation is mostly avoided by sufficiently high stack temperature. For methane as a fuel the HHV is around 11% higher than the LHV. Thus the CET derived with the LHV for a given fuel mass flow rate may be underestimated. The method comparison shown below indicates values around 10K. This is a “grey” issue. The intention of this paper is an attempt to understand this practice both technically and historically. Gas turbine catalogues indicate performance data based on burning pure methane. This may have its historic roots in the fact that methane (only Methane, not higher hydrocarbons) burns with oxygen without a change of the specific volume. This simplified the cycle calculation in the sense that combustion could be modelled by adding the LHV to air and methane (assuming an equal temperature) and by calculating the expansion of air and methane separately (corresponding to mixed if no chemical reaction due to the high temperature is assumed) but with the same polytropic efficiency. At ambient temperature this fuel-air mixture is still gaseous and therefore the heat balance of the GT matches exactly with the LHV (used before in the combustor heat balance) because there is no condensation issue. Another feature of the air may compensate the CET mistake partly when using the LHV. It is the effect of dissociation. This increases the specific heat and therefore reduces the calculated CET. In the older time the used specific heat function of air did not include the dissociation effect while nowadays it is mostly included assuming chemical equilibrium. In this paper the good match of a cycle calculation considering the HHV and dissociation with published OEM data will be demonstrated. Indeed this method contradicts existing standards and practices and a further discussion considering the evidence shown below is welcome. In its current development state it allows considering any fuel defined only by the HHV and by its composition with hydrogen to carbon ratio by mass. Additionally it also allows considering high fogging with water injection rates up to several mass % of the air inlet flow rate.

scholarly journals The electrical ignition of gaseous mixtures

1914 ◽  
Vol 90 (618) ◽  
pp. 272-297 ◽  
Keyword(s):  
X Rays ◽  
Platinum Surface ◽  
Gaseous Mixtures ◽  
Explosion Wave ◽  
Combustible Gas ◽  
Slow Combustion ◽  
The Moment ◽  
Two Stages ◽  
Hot Surface ◽  
Possible Cause

The ignition of explosive gaseous mixtures for experimental purposes is generally made by an electric spark or train of sparks between fixed terminals. The temperature of inflammation cannot in this case be measured, and it is determined by that of a hot surface in contact with the gas, or by calculation from its adiabatic compression. The fact that there is a critical temperature of ignition and that the velocity of an explosion wave can be calculated from the thermal constants of the gas and air, has led to the view that the process is a thermal one throughout, with in general two stages, a period of slow combustion and rise of temperature, and the true explosion on this reaching a certain limiting value. There is, however, a more intimate possible cause of the division of the molecule of combustible gas which precedes explosive combination. Recent work on the ionisation of gases has made familiar the view that a molecule can be ionised by corpuscular radiation, and that by the gain or loss of such corpuscles the nature of the molecule can be profoundly modified. The present paper is an examination of certain typical gases and vapours for the purpose of finding evidence of the mechanism of the process by which the energy of the source is transferred to the gas at the moment of ignition. A very full report on gaseous combustion was given by Prof. W. A. Bone at the Sheffield meeting of the British Association, in the discussion upon which Sir J. J. Thomson called attention to the possible influence of electrons in preparing the way for an explosion wave by ionising the gas. Following this suggestion an important series of observations on gaseous ignitions has been recently made by my colleague, Mr. J. R. Thompson. He found that it is possible to ignite a cold explosive mixture by the incidence of X-rays on a platinum surface in it, and that when the source of ignition is a hot platinum wire an explosion is started at that temperature at which ions are discharges from the metal. These observations, if they do not decide the ionic origin of gaseous explosions in general, prove that ionisation and explosion are intimately connected.

The Microstructure of Shock-Synthesized Diamond

1967 ◽  
Vol 25 ◽  
pp. 324-325
Author(s):  
Lucien F. Trueb
Keyword(s):  
Single Crystals ◽  
Preferred Orientation ◽  
High Magnification ◽  
Texture Pattern ◽  
Shock Process ◽  
New Type ◽  
Diffraction Diagram

A new type of synthetic industrial diamond formed by an explosive shock process has been recently developed by the Du Pont Company. This material consists of a mixture of two basically different forms, as shown in Figure 1: relatively flat and compact aggregates of acicular crystallites, and single crystals in the form of irregular polyhedra with straight edges.Figure 2 is a high magnification micrograph typical for the fibrous aggregates; it shows that they are composed of bundles of crystallites 0.05-0.3 μ long and 0.02 μ. wide. The selected area diffraction diagram (insert in Figure 2) consists of a weak polycrystalline ring pattern and a strong texture pattern with arc reflections. The latter results from crystals having preferred orientation, which shows that in a given particle most fibrils have a similar orientation.

New type electron gun with electrostatic and electromagnetic lenses

1978 ◽  
Vol 36 (1) ◽  
pp. 62-63
Author(s):  
T. Ichinokawa ◽  
H. Maeda
Keyword(s):  
Electron Microscopy ◽  
Electron Beam ◽  
Optimum Condition ◽  
Bias Voltage ◽  
Electron Gun ◽  
Charge Effect ◽  
Micro Fabrication ◽  
Maximum Brightness ◽  
New Type ◽  
The Ideal

I. IntroductionThermionic electron gun with the Wehnelt grid is popularly used in the electron microscopy and electron beam micro-fabrication. It is well known that this gun could get the ideal brightness caluculated from the Lengumier and Richardson equations under the optimum condition. However, the design and ajustment to the optimum condition is not so easy. The gun has following properties with respect to the Wehnelt bias; (1) The maximum brightness is got only in the optimum bias. (2) In the larger bias than the optimum, the brightness decreases with increasing the bias voltage on account of the space charge effect. (3) In the smaller bias than the optimum, the brightness decreases with bias voltage on account of spreading of the cross over spot due to the aberrations of the electrostatic immersion lens.In the present experiment, a new type electron gun with the electrostatic and electromagnetic lens is designed, and its properties are examined experimentally.

A new type of defect structure in 124-superconducting oxide revealed by HREM

1991 ◽  
Vol 49 ◽  
pp. 1092-1093
Author(s):  
R. Sharma ◽  
B.L. Ramakrishna ◽  
N.N. Thadhani ◽  
D. Hianes ◽  
Z. Iqbal
Keyword(s):  
Shock Wave ◽  
Defect Structure ◽  
Neutron Radiation ◽  
Weak Links ◽  
Defect Structures ◽  
New Materials ◽  
New Type ◽  
Current Densities ◽  
Processing Techniques ◽  
Microstructural Studies

After materials with superconducting temperatures higher than liquid nitrogen have been prepared, more emphasis has been on increasing the current densities (Jc) of high Tc superconductors than finding new materials with higher transition temperatures. Different processing techniques i.e thin films, shock wave processing, neutron radiation etc. have been applied in order to increase Jc. Microstructural studies of compounds thus prepared have shown either a decrease in gram boundaries that act as weak-links or increase in defect structure that act as flux-pinning centers. We have studied shock wave synthesized Tl-Ba-Cu-O and shock wave processed Y-123 superconductors with somewhat different properties compared to those prepared by solid-state reaction. Here we report the defect structures observed in the shock-processed Y-124 superconductors.

ESEM - A multipurpose surface Electron Microscope

1986 ◽  
Vol 44 ◽  
pp. 632-633 ◽  
Author(s):  
G.D. Danilatos
Keyword(s):  
Electron Microscope ◽  
Room Temperature ◽  
Environmental Scanning ◽  
Gas Composition ◽  
Saturated Water Vapor ◽  
Surface Electron ◽  
Current State ◽  
Saturated Water ◽  
New Type ◽  
Temperature And Pressure

Over recent years a new type of electron microscope - the environmental scanning electron microscope (ESEM) - has been developed for the examination of specimen surfaces in the presence of gases. A detailed series of reports on the system has appeared elsewhere. A review summary of the current state and potential of the system is presented here.The gas composition, temperature and pressure can be varied in the specimen chamber of the ESEM. With air, the pressure can be up to one atmosphere (about 1000 mbar). Environments with fully saturated water vapor only at room temperature (20-30 mbar) can be easily maintained whilst liquid water or other solutions, together with uncoated specimens, can be imaged routinely during various applications.

Trial production of γ-type energy filtering TEM

1995 ◽  
Vol 53 ◽  
pp. 604-605
Author(s):  
Y. Taniguchi ◽  
E. Nakazawa ◽  
S. Taya
Keyword(s):  
Magnetic Energy ◽  
Electron Optics ◽  
Electron Microscopic ◽  
Mass Spectrometers ◽  
Ion Optics ◽  
Energy Filtering ◽  
New Information ◽  
New Type ◽  
Fringing Fields

Imaging energy filters can add new information to electron microscopic images with respect to energy-axis, so-called electron spectroscopic imaging (ESI). Recently, many good results have been reported using this imaging technique. ESI also allows high-contrast observation of unstained biological samples, becoming a trend of the field of morphology. We manufactured a new type of energy filter as a trial production. This energy filter consists of two magnets, and we call γ-filter since the trajectory of electrons shows ‘γ’-shape inside the filter. We evaluated the new energyγ-filter TEM with the γ-filter.Figure 1 shows schematic view of the electron optics of the γ-type energy filter. For the determination of the electron-optics of the γ-type energy filter, we used the TRIO (Third Order Ion Optics) program which has been developed for the design of high resolution mass spectrometers. The TRIO takes the extended fringing fields (EFF) into consideration. EFF makes it difficult to design magnetic energy filters with magnetic sector fields.

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