Burning low volatile fuel in tangentially fired furnaces with fuel rich/lean burners

International Nuclear Information System (INIS)

Wei Xiaolin; Xu Tongmo; Hui Shien

2004-01-01

Pulverized coal combustion in tangentially fired furnaces with fuel rich/lean burners was investigated for three low volatile coals. The burners were operated under the conditions with varied value N d , which means the ratio of coal concentration of the fuel rich stream to that of the fuel lean stream. The wall temperature distributions in various positions were measured and analyzed. The carbon content in the char and NO x emission were detected under various conditions. The new burners with fuel rich/lean streams were utilized in a thermal power station to burn low volatile coal. The results show that the N d value has significant influences on the distributions of temperature and char burnout. There exists an optimal N d value under which the carbon content in the char and the NO x emission is relatively low. The coal ignition and NO x emission in the utilized power station are improved after retrofitting the burners

FIELD EVALUATION OF LOW-EMISSION COAL BURNER TECHNOLOGY ON UTILITY BOILERS VOLUME II. SECOND GENERATION LOW-NOX BURNERS

Science.gov (United States)

The report describes tests to evaluate the performance characteristics of three Second Generation Low-NOx burner designs: the Dual Register burner (DRB), the Babcock-Hitachi NOx Reducing (HNR) burner, and the XCL burner. The three represent a progression in development based on t...

Co-firing straw with coal in a swirl-stabilized dual-feed burner: modelling and experimental validation

DEFF Research Database (Denmark)

Yin, Chungen; Kær, Søren Knudsen; Rosendahl, Lasse

2010-01-01

This paper presents a comprehensive computational fluid dynamics (CFD) modelling study of co-firing wheat straw with coal in a 150 kW swirl-stabilized dual-feed burner flow reactor, in which the pulverized straw particles (mean diameter of 451μm) and coal particles (mean diameter of 110.4μm...... conversion. It is found that for pulverized biomass particles of a few hundred microns in diameter the intra-particle heat and mass transfer is a secondary issue at most in their conversion, and the global four-step mechanism of Jones and Lindstedt may be better used in modelling volatiles combustion......-lean core zone; whilst the coal particles are significantly affected by secondary air jet and swirled into the oxygen-rich outer radius with increased residence time (in average, 8.1s for coal particles vs. 5.2s for straw particles in the 3m high reactor). Therefore, a remarkable difference in the overall...

Engineering models for low-NO{sub x} burners

Energy Technology Data Exchange (ETDEWEB)

Storm Pedersen, Lars

1997-08-01

The present Ph.D. thesis describes a theoretical investigation of NO formation in pulverised coal combustion and an experimental investigation of co-combustion of straw and pulverised coal. The theoretical work has resulted in a simplified mathematical model of a swirling pulverised coal flame able to predict the NO emission and the burnout of coal. In order to simplify the flow pattern of a confined swirling flame, the residence time distribution (RTD) in a swirling pulverised coal flame was determined. This was done by using the solution of a detailed fluid dynamic mathematical model for a 2.2 MW{sub th} and a 12 MW{sub th} pulverised coal flame. From the mathematical solution the RTD was simulated by tracing a number of fluid particles or inert particles. The RTD in the near burner zone was investigated by use of the mathematical model for the 2.2 MW{sub th} and 12 MW{sub th} flame. Results showed that the gas phase in the near burner zone may be approximated as a CSTR and that the mean residence time increased with particle size. In pulverised coal flames, the most important volatile nitrogen component forming NO{sub x} is HCN. To be able to model the nitrogen chemistry in coal flames it is necessary to have an adequate model for HCN oxidation. In order to develop a model for HCN/NH{sub 3}/NO conversion, a systematic reduction of a detailed chemical kinetic model was performed. Based on the simplification of the flow pattern for a swirling flame and the reduced chemistry developed, a chemical engineering model of pulverised coal flame was established. The objectives were to predict the NO emission, the CO emission, and the burnout of char. The effects of co-firing straw and pulverised coal was investigated in a 2.5 MW{sub th} pilot-scale burner and a 250 MW{sub e} utility boiler. In the 2.5 MW{sub th} trial the straw was chopped and fed separately to the burner, whereas in the full-scale experiment the straw was pre-processed as pellets and pulverised with the

Reducing the emissions of nitrogen oxides when burning Kuznetsk bituminous coals

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R.

1983-02-01

Bituminous coals from the Kuzbass have a high nitrogen content. As a result, emissions of NO/SUB/x from power stations burning these coals frequently exceed the existing Standard. In order to reduce NO/SUB/x emissions tests were carried out using stage-wise combustion, supplying to the burners only part of the air required for complete combustion. The remaining air is supplied via tertiary nozzles situated about 14 m above the burners. As a result of the tests, this method of combustion is recommended for low-sulphur Kuznetsk coals for all sub-critical boilers having dry-bottom furnaces. Extension to boilers with wet-bottom furnaces and to supercritical boilers requires further investigation.

Evaluation of Gas Reburning and Low N0x Burners on a Wall Fired Boiler

Energy Technology Data Exchange (ETDEWEB)

None

1998-07-01

Under the U.S. Department of Energy's Clean Coal Technology Program (Round 3), a project was completed to demonstrate control of boiler NOX emissions and to a lesser degree, due to coal replacement, SO2 emissions. The project involved combining Gas Reburning with Low NOX Burners (GR-LNB) on a coal-fired electric utility boiler to determine if high levels of NO, reduction (70VO) could be achieved. Sponsors of the project included the U.S. Depatiment of Energy, the Gas Research Institute, Public Service Company of Colorado, Colorado Interstate Gas, Electric Power Research Institute, and the Energy and Environmental Research Corporation. The GR-LNB demonstration was petformed on Public Service Company of Colorado's (PSCO) Cherokee Unit #3, located in Denver, Colorado. This unit is a 172 MW~ wall-fired boiler that uses Colorado bituminous, low-sulfur coal. It had a baseline NO, emission level of 0.73 lb/1 OG Btu using conventional burners. Low NOX burners are designed to yield lower NOX emissions than conventional burners. However, the NOX control achieved with this technique is limited to 30-50Y0. Also, with LNBs, CO emissions can increase to above acceptable standards. Gas Reburning (GR) is designed to reduce NO, in the flue gas by staged fuel combustion. This technology involves the introduction of' natural gas into the hot furnace flue gas stream. When combined, GR and LNBs minimize NOX emissions and maintain acceptable levels of CO emissions. A comprehensive test program was completed, operating over a wide range of boiler conditions. Over 4,000 hours of operation were achieved, providing substantial data. Measurements were taken to quantify reductions in NOX emissions, the impact on boiler equipment and operability and factors influencing costs. The GR-LNB technology achieved good NO, emission reductions and the goals of the project were achieved. Although the performance of the low NOX burners (supplied by others) was less than expected, a NOX

PASSIVE CONTROL OF PARTICLE DISPERSION IN A PARTICLE-LADEN CIRCULAR JET USING ELLIPTIC CO-ANNULAR FLOW: A MEANS FOR IMPROVING UTILIZATION AND EMISSION REDUCTIONS IN PULVERIZED COAL BURNER

Energy Technology Data Exchange (ETDEWEB)

Ahsan R. Choudhuri

2003-06-01

A passive control technology utilizing elliptic co-flow to control the particle flinging and particle dispersion in a particle (coal)-laden flow was investigated using experimental and numerical techniques. Preferential concentration of particles occurs in particle-laden jets used in pulverized coal burner and causes uncontrollable NO{sub x} formation due to inhomogeneous local stoichiometry. This particular project was aimed at characterizing the near-field flow behavior of elliptic coaxial jets. The knowledge gained from the project will serve as the basis of further investigation on fluid-particle interactions in an asymmetric coaxial jet flow-field and thus is important to improve the design of pulverized coal burners where non-homogeneity of particle concentration causes increased NO{sub x} formation.

Reducing emission of nitrogen oxides during combustion of black coal from the Kuzbass

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R.; Lobov, G.V.; Gedike, I.A.

1983-02-01

Black coal from the Kuzbass used as fuel by the ZapSibTEhTs fossil-fuel power plant is rich in nitrogen: nitrogen content ranges from 2.8% to 3.5%. Under these conditions conventional methods of combustion cause air pollution exceeding permissible levels. A method for combustion of coal dust in stages has been successfully tested at the plant: some of the burners located in the top zone of the furnace (the BKZ-210-140F boiler) are used for air supply. From 16% to 18% of air supplied to the furnace is directed to the upper burners. Use of this system (called tertiary air supply as opposed to the secondary air system) reduced nitrogen oxide emission by 1.5 times (from 0.87 to 0.57 g/m/sup 3/). Position of nozzles used for tertiary air supply in relation to the burners used for supply of coal dust in the tangential shaped furnace is shown in a scheme. The optimum position of tertiary air supply system in relation to burners taking into account corrosion hazards as well as the hazards of reducing combustion efficiency is discussed. Recommendation on furnace design and burner position which prevent efficiency decrease and corrosion hazards are made.

Flat-flame burner studies of pulverized-coal combustion. Experimental results on char reactivity

Energy Technology Data Exchange (ETDEWEB)

Peck, R.E.; Shi, L.

1996-12-01

Structure of laminar, premixed pulverized-coal flames in a 1-D reactor has been studied with emphasis on char reactivity. A 1.1-meter-long tube furnace accommodated high-temperature environments and long residence times for the laminar flames produced by a flat-flame, coal-dust burner. Experiments were conducted at different operating conditions (fuel type/size, fuel-air ratio). Measurements included solid sample composition, major gas species and hydrocarbon species concentrations, and gas- and particle-phase line-of-sight temperatures at different axial locations in flames. Degree of char burnout increased with coal volatiles content and decreased with coal particle size. Combustion in furnace was in oxidizer-deficient environment and higher burnout was achieved as the fuel-air ratio neared stoichiometric. For 0-45 {mu}m particles most of the fixed carbon mass loss occurred within 5 cm of the furnace inlet, and char reaction was slow downstream due to low oxidizer concentrations. Fixed carbon consumption of the 45-90 {mu}m particles generally was slower than for the small particles. About 40%-80% of the fixed carbon was oxidized in the furnace. Primary volatiles mass loss occurred within the first 4.5 cm, and more than 90% of the volatiles were consumed in the flames. The flames stabilized in the furnace produced less CH{sub 4} and H{sub 2} in the burnt gas than similar unconfined flames. NO concentrations were found to decrease along the furnace and to increase with decreasing fuel/air ratio. Temperature measurement results showed that gas-phase temperatures were higher than solid-phase temperatures. Temperatures generally decreased with decreasing volatiles content and increased as the equivalence ratio approached one. The results can be used to interpret thermochemical processes occurring in pulverized-coal combustion. (au) 15 refs.

Experimental study of reduce of nitrogen oxides emission in the Environment at the Ekibastuz coal combustion

International Nuclear Information System (INIS)

Korabejnikova, V.K.

2004-01-01

For revealing conditions decrease in emissions of nitrogen oxide in an environment at three-stage burning of coal dust Ekibastuz coal with use two-line burners (on were the experimental research of test on fiery the stand as a result of which acknowledgement of theoretical results is received. (author)

Oxygen-Fired CO{sub 2} Recycle for Application to Direct CO{sub 2} Capture form Coal-Fired Power Plants

Energy Technology Data Exchange (ETDEWEB)

Thomas Gale

2010-09-26

The Southern Research/Southern Company 1 MWth Pilot-Scale Coal-Fired Test Facility was successfully retrofit to fire in either the traditional air-fired mode or with 100% oxygen and recycled flue gas, with a fully integrated feedback and control system, including oxygen and recycled flue gas modulation during startup, transfer, and shutdown, safety and operational interlocks, and data acquisition. A MAXON Staged Oxygen Burner for Oxy-Coal Applications produced a stable flame over a significant range of firing turn-down, staging, and while firing five different U.S. coal types. The MAXON burner design produces lower flame temperatures than for air firing, which will enable (A) Safe operation, (B) Reduction of recycle flow without concern about furnace flame temperatures, and (C) May likely be affective at reducing slagging and fouling in the boiler and super heater at full-scale Power Plants. A CFD model of the Oxy-fired Combustion Research Facility (OCRF) was used to predict the flame geometry and temperatures in the OCRF and make a comparison with the air-fired case. The model predictions were consistent with the experimental data in showing that the MAXON burner fired with oxygen produced lower flame temperatures than the air-fired burner while firing with air.

Low NO sub x heavy fuel combustor concept program. Phase 1A: Combustion technology generation coal gas fuels

Science.gov (United States)

Sherlock, T. P.

1982-01-01

Combustion tests of two scaled burners using actual coal gas from a 25 ton/day fluidized bed coal gasifier are described. The two combustor configurations studied were a ceramic lined, staged rich/lean burner and an integral, all metal multiannual swirl burner (MASB). The tests were conducted over a range of temperature and pressures representative of current industrial combustion turbine inlet conditions. Tests on the rich lean burner were conducted at three levels of product gas heating values: 104, 197 and 254 btu/scf. Corresponding levels of NOx emissions were 5, 20 and 70 ppmv. Nitrogen was added to the fuel in the form of ammonia, and conversion efficiencies of fuel nitrogen to NOx were on the order of 4 percent to 12 percent, which is somewhat lower than the 14 percent to 18 percent conversion efficiency when src-2 liquid fuel was used. The MASB was tested only on medium btu gas (220 to 270 btu/scf), and produced approximately 80 ppmv NOx at rated engine conditions. Both burners operated similarly on actual coal gas and erbs fuel, and all heating values tested can be successfully burned in current machines.

DEVELOPMENT OF A NOVEL RADIATIVELY/CONDUCTIVELY STABILIZED BURNER FOR SIGNIFICANT REDUCTION OF NOx EMISSIONS AND FOR ADVANCING THE MODELING AND UNDERSTANDING OF PULVERIZED COAL COMBUSTION AND EMISSIONS

Energy Technology Data Exchange (ETDEWEB)

Noam Lior; Stuart W. Churchill

2003-10-01

The primary objective of the proposed study was the study and analysis of, and design recommendations for, a novel radiatively-conductively stabilized combustion (RCSC) process for pulverized coal, which, based on our prior studies with both fluid fuels and pulverized coal, holds a high promise to reduce NO{sub x} production significantly. We have primarily engaged in continuing and improving our process modeling and analysis, obtained a large amount of quantitative information about the effects of the major parameters on NO{sub x} production, conducted an extensive exergy analysis of the process, evaluated the practicalities of employing the Radiatively-Conductively Stabilized Combustor (RCSC) to large power and heat plants, and improved the experimental facility. Prior experimental work has proven the feasibility of the combustor, but slagging during coal combustion was observed and should be dealt with. The primary outcomes and conclusions from the study are: (1) we developed a model and computer program that represents the pulverized coal combustion in the RCSC, (2) the model predicts that NO{sub x} emissions can be reduced by a number of methods, detailed in the report. (3) the exergy analysis points out at least a couple of possible ways to improve the exergetic efficiency in this combustor: increasing the effectiveness of thermal feedback, and adjusting the combustor mixture exit location, (4) because of the low coal flow rates necessitated in this study to obtain complete combustion in the burner, the size of a burner operating under the considered conditions would have to be up to an order of magnitude, larger than comparable commercial burners, but different flow configurations of the RCSC can yield higher feed rates and smaller dimensions, and should be investigated. Related to this contract, eleven papers were published in journals and conference proceedings, and ten invited presentations were given at university and research institutions, as well as at

Achievement report for fiscal 1999 on project for supporting the formation of energy/environmental technology verification project. International joint verification research project (Verification project relative to ignition and NOx reduction using plasma sub-burner in pulverized coal-fired furnace); 1999 nendo plasma sabubana ni yoru bifuntan nenshoro ni okeru chakka oyobi NO{sub x} teigen gijutsu ni kansuru jissho project seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

This project is executed through the cooperation of a Russian research institute, Akita Prefectural University, and the Ishikawajima-Harima Heavy Industries Co., Ltd. In the development of a plasma sub-burner and the basic research for its verification, a pulverized coal burning plasma sub-burner is designed and fabricated, a basic burning experiment is conducted for the plasma sub-burner, and plasma stabilization in a pulverized coal flow is simulated. In the verification study of the ignition by the plasma sub-burner in a pulverized coal-fired furnace, it is found that the newly-developed plasma sub-burner satisfies the prescribed operating conditions in the system and that the ignition of pulverized coal takes place across the air ratio range of 0.5-1.5 when pulverized coal is fed to the sub-burner. It is also found that NOx is reduced a great deal when a plasma operating on an orifice gas of air or nitrogen is generated in a gas which contains NOx. (NEDO)

IR sensor for monitoring of burner flame; IR sensor foer oevervakning av braennarflamma

Energy Technology Data Exchange (ETDEWEB)

Svanberg, Marcus; Funkquist, Jonas; Clausen, Soennik; Wetterstroem, Jonas

2007-12-15

To obtain a smooth operation of the coal-fired power plants many power plant managers have installed online mass flow measurement of coal to all burners. This signal is used to monitor the coal mass flow to the individual burner and match it with appropriate amount of air and also to monitor the distribution of coal between the burners. The online mass flow measurement system is very expensive (approximately 150 kEUR for ten burners) and is not beneficial for smaller plants. The accuracy of the measurement and the sample frequency are also questionable. The idea in this project has been to evaluate a cheaper system that can present the same information and may also provide better accuracy and faster sample frequency. The infrared sensor is a cheap narrow banded light emission sensor that can be placed in a water cooed probe. The sensor was directed at the burner flame and the emitted light was monitored. Through calibration the mass flow of coal can be presented. Two measurement campaigns were performed. Both campaigns were carried out in Nordjyllandsverket in Denmark even though the second campaign was planned to be in Uppsala. Due to severe problems in the Uppsala plant the campaign was moved to Nordjyllandsverket. The pre-requisites for the test plant were that online measurement of coal flow was installed. In Nordjyllandsverket 4 out of 16 burners have the mass flow measurement installed. Risoe Laboratories has vast experiences in the IR technology and they provided the IR sensing equipment. One IR sensor was placed in the flame guard position just behind the flame directed towards the ignition zone. A second sensor was placed at the boiler wall directed towards the flame. The boiler wall position did not give any results and the location was not used during the second campaign. The flame-guard-positioned-sensor- signal was thoroughly evaluated and the results show that there is a clear correlation between the coal mass flow and the IR sensor signal. Tests were

Low NOx firing systems for bituminous coal and lignite

International Nuclear Information System (INIS)

Knyrim, W.; Scheffknecht, G.

1997-01-01

In the case of lignite fluidized boilers the denitrification down to less than 200 mg/m 3 was possible with primary measures on the firing side only. On account of the excellent results achieved with the reconstructed plants the firing systems for the new generation of brown coal fire steam generators with a capacity of 800 MW and more is designed in a similar way. For bituminous coal fire steam generators the primary measures on the firing side are nor sufficient to keep the German NO x emission limit. Therefore these units had to be retrofitted with a SCR-DENOX plant. The experience with the new firing system made in a 110 MW steam generator in Austria with a wide range of fuels is introduced. One of the largest bituminous coal fired once-trough steam generator built by EVT is the boiler for the power station Bexbach I (750 MW). The firing system is designed as a tangential firing system with 32 jet burners. These are arranged in pairs in the corners and divided into 4 burner levels with 4 burner pairs each. One mill is allocated to each burner level. An important characteristic feature is that the four bowl mills are arranged on one side of the steam generator. The plant is constructed with upper air nozzles which are arranged above the top burner level for the reduced of nitrogen oxides. During tests at steam generator with similar design, the nO x formation could be reduced from 750 to 500 mg/m 3 s.t.p. (dry, 6% O 2 ) with an addition of upper air of 20% at 100% unit capacity and constant total flow. As a main approach for the further reduction of the primary NO x emission at bituminous coal fired steam generators with tangential firing systems, the experience gained from the firing of brown coal has also been taken into account. A fundamental aspect in this respect was the vertical air staging in the direction of the furnace height. The results of many tests in a test reactor have shown that the differences of the achievable NO x values of brown and

Influence of Coal Quality on Combustion Performance

DEFF Research Database (Denmark)

Lans, Robert Pieter Van Der; Glarborg, Peter; Dam-Johansen, Kim

1998-01-01

mixing pattern on NO formation under these conditions. Emissions from the opposed fired plant with all combustion air introduced through the burners could only be qualitatively reproduced by the pilot furnace. Under single stage conditions the test rig provided higher NO levels. Carbon in ash levels did...... not show any correlation between the coals and the furnaces. An engineering, mathematical model has been developed describing radiation heat transfer and coal combustion in full scale furnaces. The model has been validated against measured temperatures and the amount of carbon in fly ash. The model...

Proposition of primary methods for nitrogen oxides emissions reduction at coal-fired 200 MW power unit (Yugoslavia)

International Nuclear Information System (INIS)

Repic, B.; Mladenovic, R.; Crnomarkovic, N.

1997-01-01

The combustion of coal is followed by increased pollution of the environment with toxic products. Together with the generation of other pollutants, the emission of nitrogen oxides (NO x ) represents, due to its high toxicity, a great environmental risk. Appropriate measures must be taken for lowering NO x emission, both on new facilities and those already in operation. Basic technologies (primary reduction methods) of several generations, developed until now and used in practice, are presented in the paper. The technologies applicable on domestic facilities and adjusted to domestic coals have been given particular consideration. Proposition of primary methods for NO x emission reduction at coal-fired 200 MW power unit at TPS 'Nikola Tesla' is analyzed. The following methods have been considered in detail: flue gases recirculation, multi-stage combustion, low-NO x burners, additional over-fire air, multi-stage air intake into the furnace, staged fuel injection, grinding fineness increase, etc. Considerations were performed according to existing constructive characteristics of the furnace and the burners, and characteristics of used fuels, i. e. lignites from Kolubara pit. (Author)

Gradual combustion - method for nitrogen oxide suppression during brown coal combustion

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.P.; Verzakov, V.N.; Lobov, T.V.

1990-10-01

Discusses combustion of brown coal in BKZ-500-140-1 boilers and factors that influence emission of nitrogen oxides. Temperature distribution in the furnace was evaluated. Effects of burner position, burner number and burner type as well as air excess ratio on chemical reactions during brown coal combustion, formation of nitrogen oxides and their emission were comparatively evaluated. Analyses showed that by optimum arrangement of burners and selecting the optimum air excess ratio a part of nitrogen oxides formed during the initial phase of combustion was reduced to molecular nitrogen in the second phase. On the basis of evaluations the following recommendations for furnace design are made: use of straight-flow burners characterized by a reduced mixing ratio with secondary air, parallel arrangement of burners which guarantees mixing of the combustion products from the burners with stable and unstable combustion (products of incomplete coal combustion), reducing the air excess ratio to below 1.0. 5 refs.

Two-stage liquefaction of a Spanish subbituminous coal

Energy Technology Data Exchange (ETDEWEB)

Martinez, M.T.; Fernandez, I.; Benito, A.M.; Cebolla, V.; Miranda, J.L.; Oelert, H.H. (Instituto de Carboquimica, Zaragoza (Spain))

1993-05-01

A Spanish subbituminous coal has been processed in two-stage liquefaction in a non-integrated process. The first-stage coal liquefaction has been carried out in a continuous pilot plant in Germany at Clausthal Technical University at 400[degree]C, 20 MPa hydrogen pressure and anthracene oil as solvent. The second-stage coal liquefaction has been performed in continuous operation in a hydroprocessing unit at the Instituto de Carboquimica at 450[degree]C and 10 MPa hydrogen pressure, with two commercial catalysts: Harshaw HT-400E (Co-Mo/Al[sub 2]O[sub 3]) and HT-500E (Ni-Mo/Al[sub 2]O[sub 3]). The total conversion for the first-stage coal liquefaction was 75.41 wt% (coal d.a.f.), being 3.79 wt% gases, 2.58 wt% primary condensate and 69.04 wt% heavy liquids. The heteroatoms removal for the second-stage liquefaction was 97-99 wt% of S, 85-87 wt% of N and 93-100 wt% of O. The hydroprocessed liquids have about 70% of compounds with boiling point below 350[degree]C, and meet the sulphur and nitrogen specifications for refinery feedstocks. Liquids from two-stage coal liquefaction have been distilled, and the naphtha, kerosene and diesel fractions obtained have been characterized. 39 refs., 3 figs., 8 tabs.

Industrial burner and process efficiency program

Science.gov (United States)

Huebner, S. R.; Prakash, S. N.; Hersh, D. B.

1982-10-01

There is an acute need for a burner that does not use excess air to provide the required thermal turndown and internal recirculation of furnace gases in direct fired batch type furnaces. Such a burner would improve fuel efficiency and product temperature uniformity. A high velocity burner has been developed which is capable of multi-fuel, preheated air, staged combustion. This burner is operated by a microprocessor to fire in a discrete pulse mode using Frequency Modulation (FM) for furnace temperature control by regulating the pulse duration. A flame safety system has been designed to monitor the pulse firing burners using Factory Mutual approved components. The FM combustion system has been applied to an industrial batch hardening furnace (1800 F maximum temperature, 2500 lbs load capacity).

Dependence of flame length on cross sections of burners

Energy Technology Data Exchange (ETDEWEB)

Hackeschmidt, M.

1983-06-01

This article analyzes the relation between the shape of burner muzzle and the resulting flame jet in a combustion chamber. Geometrical shapes of burner muzzles, either square, circular or triangular are compared as well as proportions of flame dimensions. A formula for calculating flame lengths is derived, for which the mathematical value 'contact profile radius' for burner muzzle shape is introduced. The formula for calculating flame lengths allows a partial replacement of the empirical flame mixing factor according to N.Q. Toai, 1981. The geometrical analysis does not include thermodynamic and reaction kinetic studies, which may be necessary for evaluating heterogenous (coal dust) combustion flames with longer burning time. (12 refs.)

A chemical engineering model for predicting NO emissions and burnout from pulverised coal flames

Energy Technology Data Exchange (ETDEWEB)

Pedersen, L.S.; Glarborg, P.; Dam-Johansen, K.; Hepburn, P.W.; Hesselmann, G. [Technical University of Denmark, Lyngby (Denmark). Dept. of Chemical Engineering

1998-07-01

This work is concerned with the applicability of modelling swirling pulverised coal flames with ideal chemical reactors. The objectives were to predict the emissions of NO and CO, and the burnout of char. The fluid dynamics were simplified by use of a system of ideal chemical reactors. The near burner zone was modelled as a well-stirred reactor, the jet expansion as a plug flow reactor, the external recirculation zone as a well-stirred reactor, and the down stream zone as a number of well-stirred reactors in series. A reduced model of a detailed reaction mechanism was applied to model gas phase chemistry and a novel model was developed for soot oxidation. A population balance was used to keep track of size and density changes for the char combustion. Individual particle temperatures were calculated for each size fraction. The model includes only one burner specific calibration parameter which is related to the mixing of air and fuel. The model was validated against experimental results from a 160 kH{sub th} pulverised coal burner. For single staged combustion at varying stoichiometries, for two stage combustion, and for different coals good agreement between model and experiment was obtained for NO emissions and carbon in ash. This work also indicates that the interaction between the homogeneous gas phase chemistry and the heterogeneous chemistry (soot and char), due to recombination of radicals on the surfaces, is of importance for the nitrogen chemistry in coal flames, especially for ammonia formation. 84 refs., 31 figs., 7 tabs.

New method of reducing emission of nitrogen oxides at coal-dust burning thermal power plants in Japan

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R.

1987-05-01

New method of suppressing nitrogen oxide formation in the combustion process makes use of SGR- or PM-burners in the combustion chamber, augmented with auxiliary burners positioned higher in the chamber for secondary fuel with insufficient air and nozzles above the latter for tertiary air. A description of laboratory experiments on the reduction of nitrogen oxides using the above burner configuration as well as a description of the reaction process taking place during combustion are presented. Results of industrial testing of the three-stage combustion of high-nitrogen Australian black coal in a cylindrical combustion chamber developed by Hitachi-Zosen are presented.

Reduction of NOx and particulate emissions from coal-fired boilers by modification of coal nozzles and combustion tuning

Energy Technology Data Exchange (ETDEWEB)

Chudnovsky, B.; Talanker, A.; Mugenstein, A.; Shpon, G.; Vikhansky, A.; Elperin, T.; Bar-Ziv, E.; Bockelie, M.; Eddings, E.; Sarofim, A.F. [Israel Electric Corporation, Haifa (Israel). Engineering Division

2001-07-01

In the present paper two issues are discussed: the effect of the burner replacement on boiler performance and NOx emissions and the effect of the burner replacement on performance and efficiency of electrostatic precipitators (ESP). We also have experimented with different coal types and found the coals that together with combustion tuning met commonly accepted emission limits for NOx (less than 600 mg/dNm{sup 3}) and levels of carbon in fly ash (LOI) (approximately 5-6%) for existing boilers without low NOx burners. Our measurements were accompanied by computer simulations of the combustion of the combustion process in the boiler. Special attention was paid to detailed simulation of the flow and ignition in the near-burner zone. 7 refs., 12 figs., 5 tabs.

NOx results from two combustors tested on medium BTU coal gas

Science.gov (United States)

Sherlock, T. P.; Carl, D. E.; Vermes, G.; Schwab, J.; Notardonato, J. J.

1982-01-01

The results of tests of two combustor configurations using coal gas from a 25 ton/day fluidized bed coal gasifier are reported. The trials were run with a ceramic-lined, staged rich/lean burner and an integral, all metal multiannular swirl burner (MASB) using a range of temperatures and pressures representative of industrial turbine inlet conditions. A lean mixture was examined at 104, 197, and 254 Btu/Scf, yielding NO(x) emissions of 5, 20, and 70 ppmv, respectively. The MASB was employed only with a gas rated at 220-270 Btu/Scf, producing 80 ppmv NO(x) at rated engine conditions. The results are concluded to be transferrable to current machines. Further tests on the effects of gas composition, the scaling of combustors to utility size, and the development of improved wall cooling techniques and variable geometry are indicated.

Firing in fluid beds and burners

Energy Technology Data Exchange (ETDEWEB)

Frandsen, F.; Lans, R. van der; Storm Pedersen, L.; Philbert Nielsen, H.; Aslaug Hansen, L.; Lin, W.; Johnsson, J.E.; Dam-Johansen, K.

1998-02-01

An investigation of the effect of co-firing straw and pulverized coal was performed. Based on experiments from pilot-scale and full-scale it was concluded that a higher fraction of straw in the fuel feedstock mixture results in lower NO and SO{sub 2} emissions. The lower NO emission was mainly due to the higher volatile content of the straw, which leads to lower stoichiometry in the gas phase and in subsequent suppression of NO{sub x} formation. This conclusion is consistent with experimental and modeling results for pure coal combustion. The effect of coal quality on NO emissions has been investigated with three coals of different characteristics in three furnaces: in the Funen power station, unit 7 (FVO7), the Midtkraft Studstrup power station, unit 4 (MKS4), and the Mitsui Babcock Energy Ltd (MBEL) test-rig. The MBEL test-rig was able to reproduce qualitatively the emissions from the MKS4 plant, and quantitatively the emissions from the FVO7 plant. The better agreement between the MBEL test-rig and FVO7 is presumed to be related to the existence of a large primary zone with a relatively low stoichiometry, diminishing the influence of near burner air and fuel mixing rate on the NO emissions. An engineering model has been developed for the prediction of NO emissions and burnout from pulverized fuel combustion in swirl burners. A simplified model for reduction of N{sub 2}O in CFBC has been developed, and simulation results are in good agreement with experimental data from a 12 MW{sub th} CFB-boiler. (EG) EFP-94. 108 refs.

FIELD EVALUATION OF LOW-EMISSION COAL BURNER TECHNOLOGY ON UTILITY BOILERS VOLUME III. FIELD EVALUATIONS

Science.gov (United States)

The report gives results of field tests conducted to determine the emission characteristics of a Babcock and Wilcox Circular burner and Dual Register burner (DRB). The field tests were performed at two utility boilers, generally comparable in design and size except for the burner...

Efficiency of using direct-flow burners and nozzles in implementation of dry-bottom ash removal at the TPP-210A boiler furnace

Science.gov (United States)

Arkhipov, A. M.; Kanunnikov, A. A.; Kirichkov, V. S.; Prokhorov, V. B.; Fomenko, M. V.; Chernov, S. L.

2017-02-01

In reconstruction of operating pulverized coal-fired boilers, one of the main factors is the choice of a method for slag removal: dry bottom ash removal (DBAR) or slag-tap removal (STR). In this case, ecological and economic aspects should be taken into account, and also the early ignition of pulverized coal fuel, the reliability of operation of the furnace walls in the mode without slagging, and the stability of slag removal should be provided. In this work, issues of changeover of the pulverized coal-fired boilers of the TPP-210A type from the STR mode to the DBAR mode are considered. As of today, the main problems during the operation of these boilers are the high emissions of nitrogen oxides together with flue gases into the atmosphere and the appropriated payoffs, a small range of loads available, the necessity of stabilization of the pulverizedcoal flame sustainability by using the highly reactive fuel, large mechanical fuel underburning, etc. Results of studying aerodynamics of a furnace with DBAR obtained in the process of physical simulation are given; technical solutions and preliminary design (configuration of burners and nozzles in the boiler furnace, conceptual design of the pulverized coal burner, configuration of TPP-210A boiler with the low heat liberation of furnace cross-section and volumetric heat release) are set forth, which are associated with the optimization of aerodynamics of furnace volume, when the direct-flow burners and nozzles are used, and with organization of the efficient staged combustion of solid fuel. Two versions of possible modernization of a boiler unit are considered. Under conditions of the planned increase in the steam production capacity, the most promising measures are as follows: the DBAR implementation with reducing heat releases of the cross-section and volume of the furnace approximately by half, the installation of the direct-flow burners and nozzles with injection of recirculation gases into the active combustion

How can we reduce carbon in ash in firing pulverized coal

Energy Technology Data Exchange (ETDEWEB)

O' Keefe, W. (and others)

1992-12-01

The article discusses solutions to the problem of reducing carbon in ash in firing pulverized coal. Suggested solutions to the problem include: reviewing air flow through the mills; examining the pulverizers for coal fineness variations; investigating air distribution in the burners; review dual-firing equations; examining the burners for slag build up; checking coal fineness is appropriate to the boiler; increasing air flow; and checking instrumentation. 2 figs., 1 photo.

Investigations of coal ignition in a short-range flame burner using optical measuring systems; Untersuchungen zur Kohlezuendung am Flachflammenbrenner unter Verwendung optischer Messtechnik

Energy Technology Data Exchange (ETDEWEB)

Hackert, G.; Kremer, H.; Wirtz, S. [Bochum Univ. (Germany). Lehrstuhl fuer Energieanlagentechnik

1999-09-01

The short-range flame burner and the KOALA reactor of DMT are experimental facilities for realistic simulation of coal conversion processes at high temperatures and pressures in atmospheric conditions. The TOSCA system enable measurements of temperatures, sizes, shapes and velocities of the fuel particles, which serve as a basis for a three-dimensional simulation model of coal combustion. In the future, further parameter studies will deepen the present knowledge of coal dust combustion under pressure and enable optimisation of the numerical models for simulation of industrial-scale systems for coal dust combustion under pressure. [Deutsch] Mit dem Flachflammenbrenner und dem KOALA-Reaktor der DMT stehen Versuchsapparaturen zur Verfuegung, mit deren Hilfe die Kohleumwandlungsprozesse bei hohen Temperaturen unter Druck und unter atmosphaerischen Bedingungen realistisch wiedergegeben werden. Das TOSCA-System erlaubt dabei die Bestimmung von Temperaturen, Groessen, Formen und Geschwindigkeiten der Brennstoffpartikel. Diese Daten liefern die Grundlage fuer die Erstellung eines dreidimensionalen Simulationsmodells zur Modellierung der Kohleverbrennung. In Zukunft werden weitere Parameterstudien das Verstaendnis der Kohlenstaubdruckverbrennung vertiefen und ein Optimierung der numerischen Modelle ermoeglichen, so dass die Simulation grosstechnischer Kohlenstaubdruckverbrennungsanlagen realisiert werden kann. (orig.)

Transport fuels from two-stage coal liquefaction

Energy Technology Data Exchange (ETDEWEB)

Benito, A.; Cebolla, V.; Fernandez, I.; Martinez, M.T.; Miranda, J.L.; Oelert, H.; Prado, J.G. (Instituto de Carboquimica CSIC, Zaragoza (Spain))

1994-03-01

Four Spanish lignites and their vitrinite concentrates were evaluated for coal liquefaction. Correlationships between the content of vitrinite and conversion in direct liquefaction were observed for the lignites but not for the vitrinite concentrates. The most reactive of the four coals was processed in two-stage liquefaction at a higher scale. First-stage coal liquefaction was carried out in a continuous unit at Clausthal University at a temperature of 400[degree]C at 20 MPa hydrogen pressure and with anthracene oil as a solvent. The coal conversion obtained was 75.41% being 3.79% gases, 2.58% primary condensate and 69.04% heavy liquids. A hydroprocessing unit was built at the Instituto de Carboquimica for the second-stage coal liquefaction. Whole and deasphalted liquids from the first-stage liquefaction were processed at 450[degree]C and 10 MPa hydrogen pressure, with two commercial catalysts: Harshaw HT-400E (Co-Mo/Al[sub 2]O[sub 3]) and HT-500E (Ni-Mo/Al[sub 2]O[sub 3]). The effects of liquid hourly space velocity (LHSV), temperature, gas/liquid ratio and catalyst on the heteroatom liquids, and levels of 5 ppm of nitrogen and 52 ppm of sulphur were reached at 450[degree]C, 10 MPa hydrogen pressure, 0.08 kg H[sub 2]/kg feedstock and with Harshaw HT-500E catalyst. The liquids obtained were hydroprocessed again at 420[degree]C, 10 MPa hydrogen pressure and 0.06 kg H[sub 2]/kg feedstock to hydrogenate the aromatic structures. In these conditions, the aromaticity was reduced considerably, and 39% of naphthas and 35% of kerosene fractions were obtained. 18 refs., 4 figs., 4 tabs.

Prediction method of unburnt carbon for coal fired utility boiler using image processing technique of combustion flame

International Nuclear Information System (INIS)

Shimoda, M.; Sugano, A.; Kimura, T.; Watanabe, Y.; Ishiyama, K.

1990-01-01

This paper reports on a method predicting unburnt carbon in a coal fired utility boiler developed using an image processing technique. The method consists of an image processing unit and a furnace model unit. temperature distribution of combustion flames can be obtained through the former unit. The later calculates dynamics of the carbon reduction from the burner stages to the furnace outlet using coal feed rate, air flow rate, chemical and ash content of coal. An experimental study shows that the prediction error of the unburnt carbon can be reduced to 10%

Influence of process parameters on coal combustion performance. Review, experiments and engineering modeling

Energy Technology Data Exchange (ETDEWEB)

Lans, R.P. van der

1997-04-01

The objective of this study is to improve the understanding of nitrogen oxide formation and carbon burnout during the combustion of pulverized coal, and to contribute to addressing the potential of chemical engineering models for the prediction of furnace temperatures, NO emissions and the amount of carbon in ash. To this purpose, the effect of coal quality on NO and burnout has been investigated experimentally, a radiation heat balance has been developed based on a simple chemical engineering methodology, and a mixing study has been conducted in order to describe the near burner macro mixing in terms of a reactor configuration. The influence of coal type and process conditions on NO formation and carbon burnout has been investigated experimentally in a 400 MW{sub e} corner fired boiler with over fire air, a 350 MW{sub e} opposed fired boiler, and in a 160 kW{sub t} pilot scale test rig. Three different coals were fired in each of the furnaces as part of the activities in group 3 of the European Union JOULE 2 Extension project `Atmospheric Pressure Combustion of Pulverized Coal and Coal Based Blends for Power Generation`. On the pilot scale test both single stage and air staged tests were performed. A simple, one-dimensional combustion and radiation heat transfer model has been developed for the furnace of full scale boilers. The model has been applied to the two boilers mentioned above, and is validated against measured temperatures and carbon in ash concentrations. A mixing study has been performed in order to initiate an investigation of the potential of chemical engineering models to predict NO from pulverized fuel burners. (EG) 11 refs.

Numerical Investigation of the Low-Caloric Gas Burning Process in a Bottom Burner

Directory of Open Access Journals (Sweden)

Redko A.

2017-08-01

Full Text Available The use of low-grade gases in the fuel and energy balance of enterprises makes it possible to increase the energy efficiency of technological processes. The volumes of low-grade gases (blast furnace and coke oven gases, synthesis gas of coal gasification processes, biogas, coal gas, etc. that are utilized more significant in technological processes but their calorific value are low. At the same time artificial gases contain ballast gaseous (СО2, H2O and mechanical impurities that are harmful gas impurities. Their use requires technological preparation. Thus coal methane is characterized of high humidity, coal dust and drip moisture, variable composition. Thus was effective burning of coal methane it is required the development of constructive and regime measures that ensure a stable and complete burning of gaseous fuels. In this article it is presented the results of computer simulation of a stationary turbulent diffusion flame in a restricted space in the process of burning natural gas and coal methane in a bottom burner. The calculation results contain the fields of gear, temperature, concentration of CH4‚ CO‚ H2O‚ CO2 and nitrogen oxides. The structural elements of the flame (recirculation zone, hot "dome", mixing layer and far trace are determined. It has been established that complete combustion of coal methane in a modified bottom burner is ensured and the numerical values of nitrogen oxide concentrations in the flame are consistent with the literature data.

Acoustic Pressure Oscillations Induced in I-Burner

Science.gov (United States)

Matsui, Kiyoshi

Iwama et al. invented the I-burner to investigate acoustic combustion instability in solid-propellant rockets (Proceedings of ICT Conference, 1994, pp. 26-1 26-14). Longitudinal pressure oscillations were induced in the combustion chamber of a thick-walled rocket by combustion of a stepped-perforation grain (I-burner). These oscillations were studied here experimentally. Two I-burners with an internal diameter of 80 mm and a length of 1208 mm or 2240 mm were made. The grain had stepped perforations (20 and 42 mm in diameter and 657 and 160 mm in length, respectively). Longitudinal pressure oscillations always occur in two stages when an HTPB (hydroxyl-terminated polybutadiene)/AP (ammonium perchlorate)/aluminum-powder propellant burns (54 tests; the highest average pressure in the combustion chamber was 9.5 29 MPa), but no oscillations occur when an HTPB/AP propellant burns (29 tests). The pressure oscillations are essentially linear, but dissipation adds a nonlinear nature to them. In the first stage, the amplitudes are small and the first wave group predominates. In the next stage, the amplitudes are large and many wave groups are present. The change in the grain form accompanying the combustion affects the pressure oscillations.

Kinetics of coal liquefaction during heating-up and isothermal stages

Energy Technology Data Exchange (ETDEWEB)

Xian Li; Haoquan Hu; Shengwei Zhu; Shuxun Hu; Bo Wu; Meng Meng [Dalian University of Technology, Dalian (China). Institute of Coal Chemical Engineering

2008-04-15

Direct liquefaction of Shenhua bituminous coal was carried out in a 500 ml autoclave with iron catalyst and coal liquefaction cycle-oil as solvent at initial hydrogen of 8.0 MPa, residence time of 0-90 min. To investigate the liquefaction kinetics, a model for heating-up and isothermal stages was developed to estimate the rate constants of both stages. In the model, the coal was divided into three parts, easy reactive part, hard reactive part and unreactive part, and four kinetic constants were used to describe the reaction mechanism. The results showed that the model is valid for both heating-up and isothermal stages of liquefaction perfectly. The rate-controlled process for coal liquefaction is the reaction of preasphaltene plus asphaltene (PAA) to oil plus gas (O + G). The upper-limiting conversion of isothermal stage was estimated by the kinetic calculation. 21 refs., 4 figs., 4 tabs.

CO-FIRING COAL: FEEDLOT AND LITTER BIOMASS (CFB AND CLB) FUELS IN PULVERIZED FUEL AND FIXED BED BURNERS

Energy Technology Data Exchange (ETDEWEB)

Kalyan Annamalai; John Sweeten; Saqib Mukhtar; Ben Thein; Gengsheng Wei; Soyuz Priyadarsan; Senthil Arumugam; Kevin Heflin

2003-08-28

Intensive animal feeding operations create large amounts of animal waste that must be safely disposed of in order to avoid environmental degradation. Cattle feedlots and chicken houses are two examples. In feedlots, cattle are confined to small pens and fed a high calorie grain-diet diet in preparation for slaughter. In chicken houses, thousands of chickens are kept in close proximity. In both of these operations, millions of tons of manure are produced every year. The manure could be used as a fuel by mixing it with coal in a 90:10 blend and firing it in an existing coal suspension fired combustion systems. This technique is known as co-firing, and the high temperatures produced by the coal will allow the biomass to be completely combusted. Reburn is a process where a small percentage of fuel called reburn fuel is injected above the NO{sub x} producing, conventional coal fired burners in order to reduce NO{sub x}. The manure could also be used as reburn fuel for reducing NO{sub x} in coal fired plants. An alternate approach of using animal waste is to adopt the gasification process using a fixed bed gasifier and then use the gases for firing in gas turbine combustors. In this report, the cattle manure is referred to as feedlot biomass (FB) and chicken manure as litter biomass (LB). The report generates data on FB and LB fuel characteristics. Co-firing, reburn, and gasification tests of coal, FB, LB, coal: FB blends, and coal: LB blends and modeling on cofiring, reburn systems and economics of use of FB and LB have also been conducted. The biomass fuels are higher in ash, lower in heat content, higher in moisture, and higher in nitrogen and sulfur (which can cause air pollution) compared to coal. Small-scale cofiring experiments revealed that the biomass blends can be successfully fired, and NO{sub x} emissions will be similar to or lower than pollutant emissions when firing coal. Further experiments showed that biomass is twice or more effective than coal when

Numerical investigation into premixed hydrogen combustion within two-stage porous media burner of 1 kW solid oxide fuel cell system

Energy Technology Data Exchange (ETDEWEB)

Yen Tzu-Hsiang; Chen Bao-Dong [Refining and Manufacturing Research Institute, CPC Corporation, Chia-Yi City 60036, Taiwan (China); Hong Wen-Tang; Tsai Yu-Ching; Wang Hung-Yu; Huang Cheng-Nan; Lee Chien-Hsiung [Institute of Nuclear Energy Research Atomic Energy Council, Taoyuan County 32546, Taiwan (China)

2010-07-01

Numerical simulations are performed to analyze the combustion of the anode off-gas / cathode off-gas mixture within the two-stage porous media burner of a 1 kW solid oxide fuel cell (SOFC) system. In performing the simulations, the anode gas is assumed to be hydrogen and the combustion of the gas mixture is modeled using a turbulent flow model. The validity of the numerical model is confirmed by comparing the simulation results for the flame barrier temperature and the porous media temperature with the corresponding experimental results. Simulations are then performed to investigate the effects of the hydrogen content and the burner geometry on the temperature distribution within the burner and the corresponding operational range. It is shown that the maximum flame temperature increases with an increasing hydrogen content. In addition, it is found that the burner has an operational range of 1.2--6.5 kW when assigned its default geometry settings (i.e. a length and diameter of 0.17 m and 0.06 m, respectively), but increases to 2--9 kW and 2.6--11.5 kW when the length and diameter are increased by a factor of 1.5, respectively. Finally, the operational range increases to 3.5--16.5 kW when both the diameter and the length of the burner are increased by a factor of 1.5.

Burners. Reduction of nitrogen oxides in combustion: 2. generation of GR LONOxFLAM burner; Les bruleurs. La reduction des oxydes d`azote dans la combustion: bruleur GR LONOxFLAM de 2. generation

Energy Technology Data Exchange (ETDEWEB)

Gauthier, J.C. [EGCI Pillard, 13 - Marseille (France)

1997-12-31

This paper presents the research work carried out by the French Pillard company in collaboration with Gaz de France for the design of low NO{sub x} burners. The different type of low NO{sub x} burners are presented according to the type of fuel: gas, liquid fuels and fuel oils. The gas burner uses the fuel staging principle and the recirculation of smokes and leads to NO{sub x} emissions lower than 100 mg/Nm{sup 3}. The liquid fuel and fuel oil burners use the separate flames and the smoke self-recirculation methods (fuel-air mixture staging, reduction of flame temperature and of the residence time in flames). (J.S.)

Assessment of nitrogen oxide emission for designing boilers fired with coal dust

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R.; Gusev, L.N.; Babii, V.I.

1983-09-01

A method for forecasting emission of nitrogen oxides from steam boilers fired with coal is described. The method produces accurate results when nitrogen oxide emission from furnaces with straight-flow burners and turbulent-type burners fired with coal dusts is forecast. Oxides formed by decomposition of chemical compounds in coal (so-called 'fuel' nitrogen oxides) and nitrogen oxides formed by oxidation of molecular nitrogen by atomic oxygen (so-called 'thermal' nitrogen oxides) are evaluated. Zones in which the two types of nitrogen oxide are formed in flames are characterized. Factors which influence formation of nitrogen oxides in a furnace are evaluated: excess air, flue gas recirculation, design of a furnace and burners, movement of air and coal dust mixture in a furnace, temperature, methods for coal dust preparation, coal dust properties. Equations for forecasting emission of nitrogen oxides from furnaces are derived. Nomograms for easy calculation of emission are also given. Examples of using the method for forecasting emission of nitrogen oxides from furnaces fired with coal from the Kuzbass, the Donbass and Ehkibastuz are discussed. Comparisons of emission of nitrogen oxides calculated on the basis of the method and emission determined experimentally show that forecasting accuracy is high and errors do not exceed 10%. 5 references.

Staged fluidized-bed coal combustor for boiler retrofit

International Nuclear Information System (INIS)

Rehmat, A.; Dorfman, L.; Shibayama, G.; Waibel, R.

1991-01-01

The Advanced Staged Fluidized-Bed Coal Combustion System (ASC) is a novel clean coal technology for either coal-fired repowering of existing boilers or for incremental power generation using combined-cycle gas turbines. This new technology combines staged combustion for gaseous emission control, in-situ sulfur capture, and an ash agglomeration/vitrification process for the agglomeration/vitrification of ash and spent sorbent, thus rendering solid waste environmentally benign. The market for ASC is expected to be for clean coal-fired repowering of generating units up to 250 MW, especially for units where space is limited. The expected tightening of the environmental requirements on leachable solids residue by-products could considerably increase the marketability for ASC. ASC consists of modular low-pressure vessels in which coal is partially combusted and gasified using stacked fluidized-bed processes to produce low-to-medium-Btu, high-temperature gas. This relatively clean fuel gas is used to repower/refuel existing pulverized-coal, natural gas, or oil-fired boilers using bottom firing and reburning techniques. The benefits of ASC coal-fired repowering include the ability to repower boilers without obtaining additional space while meeting the more stringent environmental requirements of the future. Low NO x , SO x , and particulate levels are expected while a nonleachable solid residue with trace metal encapsulation is produced. ASC also minimizes boiler modification and life-extension expenditures. Repowered efficiencies can be restored to the initial operating plant efficiency, and the existing boiler capacity can be increased by 10%. Preliminary cost estimates indicate that ASC will have up to a $250/kW capital cost advantage over existing coal-fired repowering options. 4 figs., 4 tabs

Novel fragmentation model for pulverized coal particles gasification in low temperature air thermal plasma

Directory of Open Access Journals (Sweden)

Jovanović Rastko D.

2016-01-01

Full Text Available New system for start-up and flame support based on coal gasification by low temperature air thermal plasma is planned to supplement current heavy oil system in Serbian thermal power plants in order to decrease air pollutions emission and operational costs. Locally introduced plasma thermal energy heats up and ignites entrained coal particles, thus starting chain process which releases heat energy from gasified coal particles inside burner channel. Important stages during particle combustion, such as particle devolatilisation and char combustion, are described with satisfying accuracy in existing commercial CFD codes that are extensively used as powerful tool for pulverized coal combustion and gasification modeling. However, during plasma coal gasification, high plasma temperature induces strong thermal stresses inside interacting coal particles. These stresses lead to “thermal shock” and extensive particle fragmentation during which coal particles with initial size of 50-100 m disintegrate into fragments of at most 5-10 m. This intensifies volatile release by a factor 3-4 and substantially accelerates the oxidation of combustible matter. Particle fragmentation, due to its small size and thus limited influence on combustion process is commonly neglected in modelling. The main focus of this work is to suggest novel approach to pulverized coal gasification under high temperature conditions and to implement it into commercial comprehensive code ANSYS FLUENT 14.0. Proposed model was validated against experimental data obtained in newly built pilot scale D.C plasma burner test facility. Newly developed model showed very good agreement with experimental results with relative error less than 10%, while the standard built-in gasification model had error up to 25%.

Optical diagnostics to adjust burners. Een optische diagnostiek voor het instellen van branders

Energy Technology Data Exchange (ETDEWEB)

Braam, A L.H.; Hulshof, H J.M.; De Jongh, W [NV KEMA, Arnhem (Netherlands)

1991-05-01

The most efficient method to reduce nitrogen oxides in a natural gas flame or a coal flame is a correct adjustment of the burners. A newly developed optical method to measure the temperature distribution in the flame is discussed. KEMA (a Dutch Electrotechnical Equipment Testing Agency) developed the measuring method to control the combustion process in each burner of a natural gas- or coal-fired power plant for NOx formation for a constant energy production, and for the stability of the combustion. By means of data from the temperature distribution measurements some important parameters concerning NOx formation can be determined. Attention is paid to several active and passive spectroscopic methods to measure temperatures in flames. Passive spectroscopy is considered to be the best measuring method. Concentrations of radicals (CH, CN, NH) and temperature distribution are determined by means of a spectroheliograph and a camera, flame temperatures are measured by means of metal tracers. Experimental measurements carried out in the Flevo plant (EPON) are discussed. 8 figs.

300 MWe Burner Core Design with two Enrichment Zoning

International Nuclear Information System (INIS)

Song, Hoon; Kim, Sang Ji; Kim, Yeong Il

2008-01-01

KAERI has been developing the KALIMER-600 core design with a breakeven fissile conversion ratio. The core is loaded with a ternary metallic fuel (TRU-U-10Zr), and the breakeven characteristics are achieved without any blanket assembly. As an alternative plan, a KALIMER-600 burner core design has been also performed. In the early stage of the development of a fast reactor, the main purpose is an economical use of a uranium resource but nowadays in addition to the maximum utilization of a uranium resource, the burning of a high level radioactive waste is taken as an additional interest for the harmony of the environment. In way of constructing the commercial size reactor which has the power level ranging from 800 MWe to 1600 MWe, the demonstration reactor which has the power level ranging from 200 MWe to 600 MWe was usually constructed for the midterm stage to commercial size reactor. In this paper, a 300 MWe burner core design was performed with purpose of demonstration reactor for KALIMER-600 burner of 600 MWe. As a means to flatten the power distribution, instead of a single fuel enrichment scheme adapted in design of KALIMER-600 burner, the 2 enrichment zoning approach was adapted

Catalytic multi-stage liquefaction of coal at HTI: Bench-scale studies in coal/waste plastics coprocessing

Energy Technology Data Exchange (ETDEWEB)

Pradhan, V.R.; Lee, L.K.; Stalzer, R.H. [Hydrocarbon Technologies, Inc., Lawrenceville, NJ (United States)] [and others

1995-12-31

The development of Catalytic Multi-Stage Liquefaction (CMSL) at HTI has focused on both bituminous and sub-bituminous coals using laboratory, bench and PDU scale operations. The crude oil equivalent cost of liquid fuels from coal has been curtailed to about $30 per barrel, thus achieving over 30% reduction in the price that was evaluated for the liquefaction technologies demonstrated in the late seventies and early eighties. Contrary to the common belief, the new generation of catalytic multistage coal liquefaction process is environmentally very benign and can produce clean, premium distillates with a very low (<10ppm) heteroatoms content. The HTI Staff has been involved over the years in process development and has made significant improvements in the CMSL processing of coals. A 24 month program (extended to September 30, 1995) to study novel concepts, using a continuous bench scale Catalytic Multi-Stage unit (30kg coal/day), has been initiated since December, 1992. This program consists of ten bench-scale operations supported by Laboratory Studies, Modelling, Process Simulation and Economic Assessments. The Catalytic Multi-Stage Liquefaction is a continuation of the second generation yields using a low/high temperature approach. This paper covers work performed between October 1994- August 1995, especially results obtained from the microautoclave support activities and the bench-scale operations for runs CMSL-08 and CMSL-09, during which, coal and the plastic components for municipal solid wastes (MSW) such as high density polyethylene (HDPE)m, polypropylene (PP), polystyrene (PS), and polythylene terphthlate (PET) were coprocessed.

Optimisation of efficiency and emissions in pellet burners

International Nuclear Information System (INIS)

Eskilsson, David; Roennbaeck, Marie; Samuelsson, Jessica; Tullin, Claes

2004-01-01

There is a trade-off between the emissions of nitrogen oxides (NO x ) and of unburnt hydrocarbons and carbon monoxide (OGC and CO). Decreasing the excess air results in lower NO x emission but also increased emission of unburnt. The efficiency increases, as the excess air is decreased until the losses due to incomplete combustion become too high. The often-high NO x emission in today's pellet burners can be significantly reduced using well-known techniques such as air staging. The development of different chemical sensors is very intensive and recently sensors for CO and OGC have been introduced on the market. These sensors may, together with a Lambda sensor, provide efficient control for optimal performance with respect to emissions and efficiency. In this paper, results from an experimental parameter study in a modified commercial burner, followed by Chemkin simulations with relevant input data and experiments in a laboratory reactor and in a prototype burner, are summarised. Critical parameters for minimisation of NO x emission from pellet burners are investigated in some detail. Also, results from tests of a new sensor for unburnt are reported. In conclusion, relatively simple design modifications can significantly decrease NO x emission from today's pellet burners

Nitrogen oxide formation as a function of the shape of the flame in an experimental gas burner. Stikstofoxidenvorming als functie van de vlamvorm bij experimentele gasbrander

Energy Technology Data Exchange (ETDEWEB)

Hulshof, H J.M.; Thus, A W

1992-01-01

One of the options to reduce the emission of NO[sub x] from gas-fired or coal-fired power plants is to develop new burners or to improve the control of existing burners. The purpose of this investigation is to develop a measuring method to control the combustion process in each burner of a gas-fired or coal-fired power plant concerning NO[sub x]-emission, a constant energy production and stability of the combustion. A passive spectroscopic measuring method was developed, in which use is made of the light, emitted by the flame. Based on the measured values the NO[sub x]-emissions and the shape of the flame were correlated. From the correlations it appears that flame shape and NO[sub x]-emissions correspond quite well

CO-FIRING COAL, FEEDLOT, AND LITTER BIOMASS (CFB AND LFB) FUELS IN PULVERIZED FUEL AND FIXED BED BURNERS

International Nuclear Information System (INIS)

Kalyan Annamalai; John Sweeten; Saqib Mukhtar; Ben Thien; Gengsheng Wei; Soyuz Priyadarsan

2002-01-01

Intensive animal feeding operations create large amounts of animal waste that must be safely disposed of in order to avoid environmental degradation. Cattle feedlots and chicken houses are two examples. In feedlots, cattle are confined to small pens and fed a high calorie grain diet in preparation for slaughter. In chicken houses, thousands of chickens are kept in close proximity. In both of these operations, millions of tons of manure are produced every year. In this project a co-firing technology is proposed which would use manure that cannot be used for fertilizer, for power generation. Since the animal manure has economic uses as both a fertilizer and as a fuel, it is properly referred to as feedlot biomass (FB) for cow manure, or litter biomass (LB) for chicken manure. The biomass will be used a as a fuel by mixing it with coal in a 90:10 blend and firing it in existing coal fired combustion devices. This technique is known as co-firing, and the high temperatures produced by the coal will allow the biomass to be completely combusted. Therefore, it is the goal of the current research to develop an animal biomass cofiring technology. A cofiring technology is being developed by performing: (1) studies on fundamental fuel characteristics, (2) small scale boiler burner experiments, (3) gasifier experiments, (4) computer simulations, and (5) an economic analysis. The fundamental fuel studies reveal that biomass is not as high a quality fuel as coal. The biomass fuels are higher in ash, higher in moisture, higher in nitrogen and sulfur (which can cause air pollution), and lower in heat content than coal. Additionally, experiments indicate that the biomass fuels have higher gas content, release gases more readily than coal, and less homogeneous. Small-scale boiler experiments revealed that the biomass blends can be successfully fired, and NO(sub x) pollutant emissions produced will be similar to or lower than pollutant emissions when firing coal. This is a surprising

CO-FIRING COAL, FEEDLOT, AND LITTER BIOMASS (CFB AND LFB) FUELS IN PULVERIZED FUEL AND FIXED BED BURNERS

Energy Technology Data Exchange (ETDEWEB)

Kalyan Annamalai; John Sweeten; Saqib Mukhtar; Ben Thien; Gengsheng Wei; Soyuz Priyadarsan

2002-01-15

Intensive animal feeding operations create large amounts of animal waste that must be safely disposed of in order to avoid environmental degradation. Cattle feedlots and chicken houses are two examples. In feedlots, cattle are confined to small pens and fed a high calorie grain diet in preparation for slaughter. In chicken houses, thousands of chickens are kept in close proximity. In both of these operations, millions of tons of manure are produced every year. In this project a co-firing technology is proposed which would use manure that cannot be used for fertilizer, for power generation. Since the animal manure has economic uses as both a fertilizer and as a fuel, it is properly referred to as feedlot biomass (FB) for cow manure, or litter biomass (LB) for chicken manure. The biomass will be used a as a fuel by mixing it with coal in a 90:10 blend and firing it in existing coal fired combustion devices. This technique is known as co-firing, and the high temperatures produced by the coal will allow the biomass to be completely combusted. Therefore, it is the goal of the current research to develop an animal biomass cofiring technology. A cofiring technology is being developed by performing: (1) studies on fundamental fuel characteristics, (2) small scale boiler burner experiments, (3) gasifier experiments, (4) computer simulations, and (5) an economic analysis. The fundamental fuel studies reveal that biomass is not as high a quality fuel as coal. The biomass fuels are higher in ash, higher in moisture, higher in nitrogen and sulfur (which can cause air pollution), and lower in heat content than coal. Additionally, experiments indicate that the biomass fuels have higher gas content, release gases more readily than coal, and less homogeneous. Small-scale boiler experiments revealed that the biomass blends can be successfully fired, and NO{sub x} pollutant emissions produced will be similar to or lower than pollutant emissions when firing coal. This is a surprising

Pilot-Scale Demonstration of ALTA for NOx Control in Pulverized Coal-Fired Boilers

Energy Technology Data Exchange (ETDEWEB)

Andrew Fry; Devin Davis; Marc Cremer; Bradley Adams

2008-04-30

This report describes computational fluid dynamics (CFD) modeling and pilot-scale testing conducted to demonstrate the ability of the Advanced Layered Technology Approach (ALTA) to reduce NO{sub x} emissions in a pulverized coal (PC) boiler. Testing specifically focused on characterizing NO{sub x} behavior with deep burner staging combined with Rich Reagent Injection (RRI). Tests were performed in a 4 MBtu/hr pilot-scale furnace at the University of Utah. Reaction Engineering International (REI) led the project team which included the University of Utah and Combustion Components Associates (CCA). Deep burner staging and RRI, combined with selective non-catalytic reduction (SNCR), make up the Advanced Layered Technology Approach (ALTA) for NO{sub x} reduction. The application of ALTA in a PC environment requires homogenization and rapid reaction of post-burner combustion gases and has not been successfully demonstrated in the past. Operation of the existing low-NO{sub x} burner and design and operation of an application specific ALTA burner was guided by CFD modeling conducted by REI. Parametric pilot-scale testing proved the chemistry of RRI in a PC environment with a NOx reduction of 79% at long residence times and high baseline NOx rate. At representative particle residence times, typical operation of the dual-register low-NO{sub x} burner provided an environment that was unsuitable for NO{sub x} reduction by RRI, showing no NOx reduction. With RRI, the ALTA burner was able to produce NO{sub x} emissions 20% lower than the low-NO{sub x} burner, 76 ppmv vs. 94 ppmv, at a burner stoichiometric ratio (BSR) of 0.7 and a normalized stoichiometric ratio (NSR) of 2.0. CFD modeling was used to investigate the application of RRI for NO{sub x} control on a 180 MW{sub e} wall-fired, PC boiler. A NO{sub x} reduction of 37% from baseline (normal operation) was predicted using ALTA burners with RRI to produce a NO{sub x} emission rate of 0.185 lb/MBtu at the horizontal nose of

Increase of Ecological Safety, Reliability and Efficiency of Coal-Fired Boilers

Directory of Open Access Journals (Sweden)

Volkov E.P.

2017-04-01

Full Text Available The changes of environmental legislation of the Russian Federation will lead to a drastic increase of the ecological payments for environmental pollution in excess of technological standards. Significant excess in relative emissions of nitrogen oxides take place in burning solid fuel with liquid slag-tap removal. The purpose of this article was to develop technical solutions for low-cost reconstruction of the boilers to ensure efficient combustion of the fuel and technological standards of emissions of nitrogen oxides. As shown the use of straight-flow burners with compulsory optimization of the aerodynamics of the furnace and the organization of staged combustion of fuel will provide low nitrogen oxide emissions and efficient fuel combustion. Research on physical models has demonstrated the feasibility of increasing the angle of the pulverized coal burners down to 65-70o, and also achieved a more uniform distribution and increase the speed of the jets coming from upper and lower tertiary air vertical compartments of nozzles through the installation of the vertical extra sheets, which guide the flow in a space between jets. The results obtained allow the transfer of existing boilers with slag-tag removal to a solid with the installation of direct-flow burners and optimization of the aerodynamics of the furnace, which provides regulations for energy efficiency and ecological safety corresponding to the best, achieved technologies, and dramatically reduces environmental payments. The proposed technology in boiler BKZ-210-140F allowed reducing emissions of nitrogen oxides by more than 2 times when burning highly reactive Kuznetsk coal, as shown as an example.

57Fe NGR studies on three-stage hydroliquefaction of coals

International Nuclear Information System (INIS)

Jamond, M.; Bacaud, R.; Bussiere, P.; Charcosset, H.; Nickel-Pepin-Donat, B.

1990-01-01

Iron Moessbauer spectroscopy has been performed on liquefaction residues of two different French coals. In a three-stage liquefaction of high volatile bituminous coal (Freyming), without an added catalyst, the coal pyrite is not entirely converted into pyrrhotites, whereas in the presence of an added catalyst, coal pyrite is totally transformed into more dispersed pyrrhotites than those from the sample without an added catalyst; furthermore, the whole added catalyst precursor is reduced into pyrrhotites. In the case of liquefaction of subbituminous coal (Gardanne), full conversion of coal pyrite into pyrrhotites (even without an added catalyst) occurs. In addition, in the presence of the added catalyst, besides pyrrhotites, FeS is evidenced. When molybdenum-iron oxide is added as a catalyst precursor, no mixed Fe-Mo phase is detected. (orig.)

Two-stage catalytic up-grading of vacuum residue of a Wandoan coal liquid. [Vacuum residue of coal liquid

Energy Technology Data Exchange (ETDEWEB)

Mochida, I.; Sakanishi, K.; Korai, Y.; Fujitsu, H.

1986-08-01

A successive two-stage hydrotreatment using a commercial Ni-Mo/Al/sub 2/O/sub 3/ catalyst (HDN-30) was applied to the vacuum residue of a Wandoan coal liquid to achieve high levels of hydrocracking, hydrodenitrogenation and hydrodeoxygenation. Two-stage hydrotreatment in 1-methylnaphthalene containing 20wt% fluoranthene as a solvent at solvent/coal liquid ratio of unity removed 83% (overall) of nitrogen and 90% (overall) of oxygen in the asphaltene (benzene-soluble fraction) at 380/sup 0/C for 3 h and at 420/sup 0/C for 3h under hydrogen pressure of 15 MPa and 14 MPa, respectively, while the single stage treatment at 420/sup 0/C for 3 h removed only 41% and 46%, respectively. The same two-stage treatment allowed the overall denitrogenation of 51% and the overall deoxygenation of 67% from a mixture of asphaltene and preasphaltene (THF-soluble fraction). Addition of the catalyst prior to the second stage reaction increased the removal of nitrogen and oxygen to 75 and 82%, respectively, indicating significant catalyst deactivation by the preasphaltene fraction in the first stage. Increasing the solvent/coal liquid ratio to 2 or addition of tetrahydrofluoranthene as a component of the solvent increased the removal of nitrogen and oxygen to 70 and 80%, respectively. Such two-stage hydrotreatment was also effective in refining the whole residue, allowing denitrogenations and deoxygenations of 68 and 75% respectively using tetrahydrofluoranthene. The coke, unreacted coal and minerals in the residue may not cause acute catalyst deactivation. High dissolving ability of the reaction solvents is very effective to decrease catalyst deactivation by carbon deposition. The successive two-stage hydrotreatment also enhanced hydrocracking of polar and resin fractions in the residue into oils (conversion, 65%). (Abstract Truncated)

Pulverized straw combustion in a low-NOx multifuel burner

DEFF Research Database (Denmark)

Mandø, Matthias; Rosendahl, Lasse; Yin, Chungen

2010-01-01

A CFD simulation of pulverized coal and straw combustion using a commercial multifuel burner have been undertaken to examine the difference in combustion characteristics. Focus has also been directed to development of the modeling technique to deal with larger non-spherical straw particles...... and to determine the relative importance of different modeling choices for straw combustion. Investigated modeling choices encompass the particle size and shape distribution, the modification of particle motion and heating due to the departure from the spherical ideal, the devolatilization rate of straw......, the influence of inlet boundary conditions and the effect of particles on the carrier phase turbulence. It is concluded that straw combustion is associated with a significantly longer flame and smaller recirculation zones compared to coal combustion for the present air flow specifications. The particle size...

CFD study of temperature distribution in full scale boiler adopting in-furnace coal blending

International Nuclear Information System (INIS)

Fadhil, S S A; Hasini, H; Shuaib, N H

2013-01-01

This paper describes the investigation of temperature characteristics of an in-furnace combustion using different coals in a 700 MW full scale boiler. Single mixture fraction approach is adopted for combustion model of both primary and secondary coals. The primary coal was based on the properties of Adaro which has been used as the design coal for the boiler under investigation. The secondary blend coal was selected based on sub-bituminous coal with higher calorific value. Both coals are simultaneously injected into the furnace at alternate coal burner elevations. The general prediction of the temperature contours at primary combustion zone shows identical pattern compared with conventional single coal combustion in similar furnace. Reasonable agreement was achieved by the prediction of the average temperature at furnace exit. The temperature distribution is at different furnace elevation is non-uniform with higher temperature predicted at circumferential 'ring-like' region at lower burner levels for both cases. The maximum flame temperature is higher at the elevation where coal of higher calorific value is injected. The temperature magnitude is within the accepTable limit and the variations does not differ much compared to the conventional single coal combustion.

Oxy-coal Combustion Studies

Energy Technology Data Exchange (ETDEWEB)

Wendt, J. [Univ. of Utah, Salt Lake City, UT (United States); Eddings, E. [Univ. of Utah, Salt Lake City, UT (United States); Lighty, J. [Univ. of Utah, Salt Lake City, UT (United States); Ring, T. [Univ. of Utah, Salt Lake City, UT (United States); Smith, P. [Univ. of Utah, Salt Lake City, UT (United States); Thornock, J. [Univ. of Utah, Salt Lake City, UT (United States); Y Jia, W. Morris [Univ. of Utah, Salt Lake City, UT (United States); Pedel, J. [Univ. of Utah, Salt Lake City, UT (United States); Rezeai, D. [Univ. of Utah, Salt Lake City, UT (United States); Wang, L. [Univ. of Utah, Salt Lake City, UT (United States); Zhang, J. [Univ. of Utah, Salt Lake City, UT (United States); Kelly, K. [Univ. of Utah, Salt Lake City, UT (United States)

2012-01-06

The objective of this project is to move toward the development of a predictive capability with quantified uncertainty bounds for pilot-scale, single-burner, oxy-coal operation. This validation research brings together multi-scale experimental measurements and computer simulations. The combination of simulation development and validation experiments is designed to lead to predictive tools for the performance of existing air fired pulverized coal boilers that have been retrofitted to various oxy-firing configurations. In addition, this report also describes novel research results related to oxy-combustion in circulating fluidized beds. For pulverized coal combustion configurations, particular attention is focused on the effect of oxy-firing on ignition and coal-flame stability, and on the subsequent partitioning mechanisms of the ash aerosol.

Combustion of producer gas from gasification of south Sumatera lignite coal using CFD simulation

Directory of Open Access Journals (Sweden)

Vidian Fajri

2017-01-01

Full Text Available The production of gasses from lignite coal gasification is one of alternative fuel for the boiler or gas turbine. The prediction of temperature distribution inside the burner is important for the application and optimization of the producer gas. This research aims to provide the information about the influence of excess air on the temperature distribution and combustion product in the non-premixed burner. The process was carried out using producer gas from lignite coal gasification of BA 59 was produced by the updraft gasifier which is located on Energy Conversion Laboratory Mechanical Engineering Department Universitas Sriwijaya. The excess air used in the combustion process were respectively 10%, 30% and 50%. CFD Simulations was performed in this work using two-dimensional model of the burner. The result of the simulation showed an increase of excess air, a reduction in the gas burner temperature and the composition of gas (carbon dioxide, nitric oxide and water vapor.

COST-EFFECTIVE CONTROL OF NOx WITH INTEGRATED ULTRA LOW-NOx BURNERS AND SNCR

International Nuclear Information System (INIS)

Hamid Farzan

2001-01-01

Coal-fired electric utilities are facing a serious challenge with regards to curbing their NO(sub x) emissions. At issue are the NO(sub x) contributions to the acid rain, ground level ozone, and particulate matter formation. Substantial NO(sub x) control requirements could be imposed under the proposed Ozone Transport Rule, National Ambient Air Quality Standards, and New Source Performance Standards. McDermott Technology, Inc. (MTI), Babcock and Wilcox (B and W), and Fuel Tech are teaming to provide an integrated solution for NO(sub x) control. The system will be comprised of an ultra low-NO(sub x) pulverized coal (PC) burner technology plus a urea-based, selective non-catalytic reduction (SNCR) system. This system will be capable of meeting a target emission limit of 0.15 lb NO(sub x)/10(sup 6) Btu and target ammonia (NH3) slip level targeted below 5 ppmV for commercial units. Our approach combines the best available combustion and post-combustion NO(sub x) control technologies. More specifically, B and W's DRB-4Z TM ultra low-NO(sub x) PC burner technology will be combined with Fuel Tech's NO(sub x)OUT (SNCR) and NO(sub x)OUT Cascade (SNCR/SCR hybrid) systems and jointly evaluated and optimized in a state-of-the-art test facility at MTI. Although the NO(sub x)OUT Cascade (SNCR/SCR hybrid) system will not be tested directly in this program, its potential application for situations that require greater NO(sub x) reductions will be inferred from other measurements (i.e., SNCR NO(sub x) removal efficiency plus projected NO(sub x) reduction by the catalyst based on controlled ammonia slip). Our analysis shows that the integrated ultra low-NO(sub x) burner and SNCR system has the lowest cost when the burner emissions are 0.25 lb NO(sub x)/10(sup 6) Btu or less. At burner NO(sub x) emission level of 0.20 lb NO(sub x)/10(sup 6) Btu, the levelized cost per ton of NO(sub x) removed is 52% lower than the SCR cost

Numerical investigation of influence thermal preparation coal on nitric oxides formation in combustion process

Energy Technology Data Exchange (ETDEWEB)

Chernetskaya, N. [Siberian Federal Univ., Krasnoyarsk (Russian Federation); Chernetsky, M.; Dekterev, A. [Siberian Federal Univ., Krasnoyarsk (Russian Federation); Kutateladze Institute of Thermophysics, Novosibirsk (Russian Federation)

2013-07-01

Emissions of nitrogen oxides from coal combustion are a major environmental problem because they have been shown to contribute to the formation of acid rain and photochemical smog. Coal thermalpreparation before furnace delivery is effective method to reduce NOx emissions, shown by experiments in small-scale facilities (Babiy VI, Alaverdov PI, Influence of thermal preparation pulverized coal on nitric oxides outlet for combustion different metamorphized coal. ATI, 1983). This paper presents the mathematical model of burning thermal preparation coal. Validation of the model was carried out on laboratory-scale plant of All-Russia thermal engineering institute. Modeling of low-emissive burner with preliminary heating coal dust is made for the purpose of search of burner optimal constructions which provides low concentration of nitric oxides in the boiler. For modeling are used in-house CFD code ''{sigma}Flow'' (Dekterev AA, Gavrilov AA, Harlamov EB, Litvintcev KY, J Comput Technol 8(Part 1):250-255, 2003).

A collaborative project on the effects of coal quality on NO{sub x} emissions and carbon burnout in pulverised coal-fired utility boilers

Energy Technology Data Exchange (ETDEWEB)

Tilley, H.A.; O`Connor, M.; Stephenson, P.L.; Whitehouse, M.; Richards, D.G.; Hesselmann, G.; MacPhail, J.; Lockwood, F.C.; Williamson, J.; Williams, A.; Pourkashanian, M. [ETSU, Harwell (United Kingdom)

1998-12-01

This paper describes a UK Department of Trade and Industry-supported collaborative project entitled `The Effects of Coal Quality on Emission of Oxides of Nitrogen (NO{sub x}) and Carbon Burnout in Pulverised Coal-fired Utility Boilers`. The project involved extensive collaboration between the UK power generators, boiler and burner manufacturers and research groups in both industry and academia, together with several of the world`s leading computational fluid dynamics (CFD) `software houses`. The prime objectives of the project were to assess the relationship between NO{sub x} emissions and carbon burnout and to develop and validate predictive tools for assessing coals. Experimental work was carried out on various laboratory-scale apparatus and on single burner test facilities ranging from 160 kW{sub th} to 40 MW{sub th} in size and measurements were obtained from full-scale 500 MW{sub e} utility boiler trials. This data and basic coal data were then used to develop mathematical models to predict full-scale boiler performance with respect to NO{sub x} emissions and carbon-in-ash. Results showed good correlations for NO{sub x} and carbon burnout when comparing data from full-scale and large-scale rig trials. Laboratory-scale tests were found to be useful but the influence of burner aerodynamics was more difficult to quantify. Modelling showed that predicted NO{sub x} emissions were encouragingly close to measured emissions but predicting carbon burnout was less successful. 24 refs., 4 figs., 6 tabs.

DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL

International Nuclear Information System (INIS)

Larry G. Felix; P. Vann Bush

2002-01-01

This is the sixth Quarterly Technical Report for DOE Cooperative Agreement No. DE-FC26-00NT40895. A statement of the project objectives is included in the Introduction of this report. Two additional biomass co-firing test burns were conducted during this quarter. In the first test (Test 10), up to 20% by weight dry hardwood sawdust and switchgrass was compiled with Galatia coal and injected through the dual-register burner. Galatia coal is a medium-sulfur Illinois Basin coal ((approx)1.0% S). The dual-register burner is a generic low-NO(sub x) burner that incorporates two independent wind boxes. In the second test (Test 11), regular ((approx)70% passing 200 mesh) and finely ground ((approx)90% passing 200 mesh) Pratt Seam coal was injected through the single-register burner to determine if coal grind affects NO(sub x) and unburned carbon emissions. The results of these tests are presented in this quarterly report. Significant progress has been made in implementing a modeling approach to combine reaction times and temperature distributions from computational fluid dynamic models of the pilot-scale combustion furnace with char burnout and chemical reaction kinetics to predict NO(sub x) emissions and unburned carbon levels in the furnace exhaust. No additional results of CFD modeling have been received as delivery of the Configurable Fireside Simulator is expected during the next quarter. Preparations are under way for continued pilot-scale combustion experiments with the single-register burner and a low-volatility bituminous coal. Some delays have been experienced in the acquisition and processing of biomass. Finally, a project review was held at the offices of Southern Research in Birmingham, on February 27, 2002

Combustion of coal gas fuels in a staged combustor

Science.gov (United States)

Rosfjord, T. J.; Mcvey, J. B.; Sederquist, R. A.; Schultz, D. F.

1982-01-01

Gaseous fuels produced from coal resources generally have heating values much lower than natural gas; the low heating value could result in unstable or inefficient combustion. Coal gas fuels may contain ammonia which if oxidized in an uncontrolled manner could result in unacceptable nitrogen oxide exhaust emission levels. Previous investigations indicate that staged, rich-lean combustion represents a desirable approach to achieve stable, efficient, low nitrogen oxide emission operation for coal-derived liquid fuels contaning up to 0.8-wt pct nitrogen. An experimental program was conducted to determine whether this fuel tolerance can be extended to include coal-derived gaseous fuels. The results of tests with three nitrogen-free fuels having heating values of 100, 250, and 350 Btu/scf and a 250 Btu/scf heating value doped to contain 0.7 pct ammonia are presented.

40 CFR Appendix A to Part 76 - Phase I Affected Coal-Fired Utility Units With Group 1 or Cell Burner Boilers

Science.gov (United States)

2010-07-01

... Units With Group 1 or Cell Burner Boilers A Appendix A to Part 76 Protection of Environment... 1 or Cell Burner Boilers Table 1—Phase I Tangentially Fired Units State Plant Unit Operator ALABAMA... Vertically fired boiler. 2 Arch-fired boiler. Table 3—Phase I Cell Burner Technology Units State Plant Unit...

Burners. The decrease of nitrogen oxides in combustion process: the 2 nd generation GR LONOxFLAM burner; Les bruleurs, la reduction des oxydes d`azote dans la combustion: bruleur GR LONOxFLAM de 2. generation

Energy Technology Data Exchange (ETDEWEB)

Gauthier, J.C. [EGCI Pillard, 13 - Marseille (France)

1997-12-31

The Pillard company has developed, in cooperation with GDF (the French national gas utility), the GR-LONOxFLAM burner concept for reducing NOx emission levels and solid combustion products. The concept consists, for gaseous fuels, in the combination of an internal recirculation and a gas staging process; for liquid fuels, a separated flame process and air staging are combined. These concepts allow for an important reduction in NOx and non-burned residues, even with standard-size burners

High conversion burner type reactor

International Nuclear Information System (INIS)

Higuchi, Shin-ichi; Kawashima, Masatoshi

1987-01-01

Purpose: To simply and easily dismantle and reassemble densified fuel assemblies taken out of a high conversion ratio area thereby improve the neutron and fuel economy. Constitution: The burner portion for the purpose of fuel combustion is divided into a first burner region in adjacent with the high conversion ratio area at the center of the reactor core, and a second burner region formed to the outer circumference thereof and two types of fuels are charged therein. Densified fuel assemblies charged in the high conversion ratio area are separatably formed as fuel assemblies for use in the two types of burners. In this way, dense fuel assembly is separated into two types of fuel assemblies for use in burner of different number and arranging density of fuel elements which can be directly charged to the burner portion and facilitate the dismantling and reassembling of the fuel assemblies. Further, since the two types of fuel assemblies are charged in the burner portion, utilization factor for the neutron fuels can be improved. (Kamimura, M.)

Distributed activation energy model for kinetic analysis of multi-stage hydropyrolysis of coal

Energy Technology Data Exchange (ETDEWEB)

Liu, X.; Li, W.; Wang, N.; Li, B. [Chinese Academy of Sciences, Taiyuan (China). Inst. of Coal Chemistry

2003-07-01

Based on the new analysis of distributed activation energy model, a bicentral distribution model was introduced to the analysis of multi-stage hydropyrolysis of coal. The hydropyrolysis for linear temperature programming with and without holding stage were mathematically described and the corresponding kinetic expressions were achieved. Based on the kinetics, the hydropyrolysis (HyPr) and multi-stage hydropyrolysis (MHyPr) of Xundian brown coal was simulated. The results shows that both Mo catalyst and 2-stage holding can lower the apparent activation energy of hydropyrolysis and make activation energy distribution become narrow. Besides, there exists an optimum Mo loading of 0.2% for HyPy of Xundian lignite. 10 refs.

The Technology of Nitrogen Oxide Emissions Reduction at Pulverized Coal Burning

Directory of Open Access Journals (Sweden)

Dunaevska, N.I.

2016-11-01

Full Text Available To assess the effectiveness of the influence of thermochemical preparation of anthracite on the formation of nitrogen oxides the three-dimensional numerical model of the TPP-210A boiler`s furnace for standard and modified burners was created. The calculation results are shown the decrease of NOx concentration across the height of the furnace and reduce of the unburnt coal for the modified burners in comparison with standard ones.

Burners and combustion apparatus for carbon nanomaterial production

Science.gov (United States)

Alford, J. Michael; Diener, Michael D; Nabity, James; Karpuk, Michael

2013-02-05

The invention provides improved burners, combustion apparatus, and methods for carbon nanomaterial production. The burners of the invention provide sooting flames of fuel and oxidizing gases. The condensable products of combustion produced by the burners of this invention produce carbon nanomaterials including without limitation, soot, fullerenic soot, and fullerenes. The burners of the invention do not require premixing of the fuel and oxidizing gases and are suitable for use with low vapor pressure fuels such as those containing substantial amounts of polyaromatic hydrocarbons. The burners of the invention can operate with a hot (e.g., uncooled) burner surface and require little, if any, cooling or other forms of heat sinking. The burners of the invention comprise one or more refractory elements forming the outlet of the burner at which a flame can be established. The burners of the invention provide for improved flame stability, can be employed with a wider range of fuel/oxidizer (e.g., air) ratios and a wider range of gas velocities, and are generally more efficient than burners using water-cooled metal burner plates. The burners of the invention can also be operated to reduce the formation of undesirable soot deposits on the burner and on surfaces downstream of the burner.

Coal - 96

International Nuclear Information System (INIS)

Sparre, C.

1996-09-01

The report deals mainly with coal consumption, but also gives some information about technology, environmental aspects and markets. Data have been collected by questionnaires or via telephone. The use of steam coal for heating was 0.8 Mtons (down 20% from 1994). Cogeneration plants were the main users. Taxes and environmental reasons cause a reduction of the coal use that will probably continue the next years. Use of steam coal in industry has been constant at a level of 0.7 Mtons. The import of metallurgical coal rests constant at a level of 1.6 Mtons. 1.2 Mtons of coke was produced, and 0.3 Mtons imported. The PFBC-plant at Vaertan, Stockholm used 0.13 Mtons of coal, while some coal fired power plants have been converted to peat and wood fuels. The average price of steam coal imported to Sweden in 1995 was 333 SEK/ton, 6% higher than in 1994. The contract prices for delivery 1996 are about the same as at the end of 1995. All cogeneration plants have some sort of SO 2 removal system, mostly wet-dry. The largest plant, at Vaesteraas, has recently invested in a SCR system for NO x removal. Most other plants are using low NO x burners or SNCR systems, based on ammonia or urea, which reduce the emissions 50 - 70%. Some statistic about the world coal market is also given in the report

Radial lean direct injection burner

Science.gov (United States)

Khan, Abdul Rafey; Kraemer, Gilbert Otto; Stevenson, Christian Xavier

2012-09-04

A burner for use in a gas turbine engine includes a burner tube having an inlet end and an outlet end; a plurality of air passages extending axially in the burner tube configured to convey air flows from the inlet end to the outlet end; a plurality of fuel passages extending axially along the burner tube and spaced around the plurality of air passage configured to convey fuel from the inlet end to the outlet end; and a radial air swirler provided at the outlet end configured to direct the air flows radially toward the outlet end and impart swirl to the air flows. The radial air swirler includes a plurality of vanes to direct and swirl the air flows and an end plate. The end plate includes a plurality of fuel injection holes to inject the fuel radially into the swirling air flows. A method of mixing air and fuel in a burner of a gas turbine is also provided. The burner includes a burner tube including an inlet end, an outlet end, a plurality of axial air passages, and a plurality of axial fuel passages. The method includes introducing an air flow into the air passages at the inlet end; introducing a fuel into fuel passages; swirling the air flow at the outlet end; and radially injecting the fuel into the swirling air flow.

LOW NOX BURNER DEVELOPMENT

Energy Technology Data Exchange (ETDEWEB)

KRISHNA,C.R.; BUTCHER,T.

2004-09-30

The objective of the task is to develop concepts for ultra low NOx burners. One approach that has been tested previously uses internal recirculation of hot gases and the objective was to how to implement variable recirculation rates during burner operation. The second approach was to use fuel oil aerosolization (vaporization) and combustion in a porous medium in a manner similar to gas-fired radiant burners. This task is trying the second approach with the use of a somewhat novel, prototype system for aerosolization of the liquid fuel.

Multi-stage combustion using nitrogen-enriched air

Science.gov (United States)

Fischer, Larry E.; Anderson, Brian L.

2004-09-14

Multi-stage combustion technology combined with nitrogen-enriched air technology for controlling the combustion temperature and products to extend the maintenance and lifetime cycles of materials in contact with combustion products and to reduce pollutants while maintaining relatively high combustion and thermal cycle efficiencies. The first stage of combustion operates fuel rich where most of the heat of combustion is released by burning it with nitrogen-enriched air. Part of the energy in the combustion gases is used to perform work or to provide heat. The cooled combustion gases are reheated by additional stages of combustion until the last stage is at or near stoichiometric conditions. Additional energy is extracted from each stage to result in relatively high thermal cycle efficiency. The air is enriched with nitrogen using air separation technologies such as diffusion, permeable membrane, absorption, and cryogenics. The combustion method is applicable to many types of combustion equipment, including: boilers, burners, turbines, internal combustion engines, and many types of fuel including hydrogen and carbon-based fuels including methane and coal.

Thermogravimetric analysis of multi-stage hydropyrolysis of different coals

Energy Technology Data Exchange (ETDEWEB)

Li, W.; Wang, N.; Li, B [Chinese Academy of Sciences, Taiyuan (China). State Key Lab. of Coal Conversion

2001-09-01

Based on the characteristic of hydropyrolysis (HyPy), a multi-stage MHyPy of different coals was investigated using thermogravimetry. The results show that keeping the near peak temperature for some time in HyPy process can obviously increase the conversion rate, which is believed due to the full match between formation rate of free radicals and supply of hydrogen. The fast heating in MHyPy process results in the same conversion rate as that of the slow heating in HyPy process, which leads to the less reaction time and high yield of oil. The effect of MHyPy depends on the coal structure itself and it is notable for the coal with high H/C ratio. This suggests that the external hydrogen promotes the reaction between intrinsic hydrogen and free radicals. The MHyPy improves the removal of sulfur and nitrogen. 5 refs., 7 figs., 2 tabs.

Numerical simulation of porous burners and hole plate surface burners

Directory of Open Access Journals (Sweden)

Nemoda Stevan

2004-01-01

Full Text Available In comparison to the free flame burners the porous medium burners, especially those with flame stabilization within the porous material, are characterized by a reduction of the combustion zone temperatures and high combustion efficiency, so that emissions of pollutants are minimized. In the paper the finite-volume numerical tool for calculations of the non-isothermal laminar steady-state flow, with chemical reactions in laminar gas flow as well as within porous media is presented. For the porous regions the momentum and energy equations have appropriate corrections. In the momentum equations for the porous region an additional pressure drop has to be considered, which depends on the properties of the porous medium. For the heat transfer within the porous matrix description a heterogeneous model is considered. It treats the solid and gas phase separately, but the phases are coupled via a convective heat exchange term. For the modeling of the reaction of the methane laminar combustion the chemical reaction scheme with 164 reactions and 20 chemical species was used. The proposed numerical tool is applied for the analyses of the combustion and heat transfer processes which take place in porous and surface burners. The numerical experiments are accomplished for different powers of the porous and surface burners, as well as for different heat conductivity character is tics of the porous regions.

METHANE de-NOX for Utility PC Boilers

Energy Technology Data Exchange (ETDEWEB)

Bruce Bryan; Serguei Nester; Joseph Rabovitser; Stan Wohadlo

2005-09-30

The overall project objective is the development and validation of an innovative combustion system, based on a novel coal preheating concept prior to combustion, that can reduce NO{sub x} emissions to 0.15 lb/million Btu or less on utility pulverized coal (PC) boilers. This NO{sub x} reduction should be achieved without loss of boiler efficiency or operating stability, and at more than 25% lower levelized cost than state-of-the-art SCR technology. A further objective is to ready technology for full-scale commercial deployment to meet the market demand for NO{sub x} reduction technologies. Over half of the electric power generated in the U.S. is produced by coal combustion, and more than 80% of these units utilize PC combustion technology. Conventional measures for NOx reduction in PC combustion processes rely on combustion and post-combustion modifications. A variety of combustion-based NO{sub x} reduction technologies are in use today, including low-NO{sub x} burners (LNBs), flue gas recirculation (FGR), air staging, and natural gas or other fuel reburning. Selective non-catalytic reduction (SNCR) and selective catalytic reduction (SCR) are post-combustion techniques. NO{sub x} reduction effectiveness from these technologies ranges from 30 to 60% and up to 90-93% for SCR. Typically, older wall-fired PC burner units produce NO{sub x} emissions in the range of 0.8-1.6 lb/million Btu. Low-NO{sub x} burner systems, using combinations of fuel staging within the burner and air staging by introduction of overfire air in the boiler, can reduce NO{sub x} emissions by 50-60%. This approach alone is not sufficient to meet the desired 0.15 lb/million Btu NO{sub x} standard with a range of coals and boiler loads. Furthermore, the heavy reliance on overfire air can lead to increased slagging and corrosion in furnaces, particularly with higher-sulfur coals, when LNBs are operated at sub-stoichiometric conditions to reduce fuel-derived NOx in the flame. Therefore, it is desirable

Measurement of gas species, temperatures, coal burnout, and wall heat fluxes in a 200 MWe lignite-fired boiler with different overfire air damper openings

Energy Technology Data Exchange (ETDEWEB)

Jianping Jing; Zhengqi Li; Guangkui Liu; Zhichao Chen; Chunlong Liu [Harbin Institute of Technology, Harbin (China). School of Energy Science and Engineering

2009-07-15

Measurements were performed on a 200 MWe, wall-fired, lignite utility boiler. For different overfire air (OFA) damper openings, the gas temperature, gas species concentration, coal burnout, release rates of components (C, H, and N), furnace temperature, and heat flux and boiler efficiency were measured. Cold air experiments for a single burner were conducted in the laboratory. The double-swirl flow pulverized-coal burner has two ring recirculation zones starting in the secondary air region in the burner. As the secondary air flow increases, the axial velocity of air flow increases, the maxima of radial velocity, tangential velocity and turbulence intensity all increase, and the swirl intensity of air flow and the size of recirculation zones increase slightly. In the central region of the burner, as the OFA damper opening widens, the gas temperature and CO concentration increase, while the O{sub 2} concentration, NOx concentration, coal burnout, and release rates of components (C, H, and N) decrease, and coal particles ignite earlier. In the secondary air region of the burner, the O{sub 2} concentration, NOx concentration, coal burnout, and release rates of components (C, H, and N) decrease, and the gas temperature and CO concentration vary slightly. In the sidewall region, the gas temperature, O{sub 2} concentration, and NOx concentration decrease, while the CO concentration increases and the gas temperature varies slightly. The furnace temperature and heat flux in the main burning region decrease appreciably, but increase slightly in the burnout region. The NOx emission decreases from 1203.6 mg/m{sup 3} (6% O{sub 2}) for a damper opening of 0% to 511.7 mg/m{sup 3} (6% O{sub 2}) for a damper opening of 80% and the boiler efficiency decreases from 92.59 to 91.9%. 15 refs., 17 figs., 3 tabs.

A new scaling methodology for NO(x) emissions performance of gas burners and furnaces

Science.gov (United States)

Hsieh, Tse-Chih

1997-11-01

A general burner and furnace scaling methodology is presented, together with the resulting scaling model for NOsb{x} emissions performance of a broad class of swirl-stabilized industrial gas burners. The model is based on results from a set of novel burner scaling experiments on a generic gas burner and furnace design at five different scales having near-uniform geometric, aerodynamic, and thermal similarity and uniform measurement protocols. These provide the first NOsb{x} scaling data over the range of thermal scales from 30 kW to 12 MW, including input-output measurements as well as detailed in-flame measurements of NO, NOsb{x}, CO, Osb2, unburned hydrocarbons, temperature, and velocities at each scale. The in-flame measurements allow identification of key sources of NOsb{x} production. The underlying physics of these NOsb{x} sources lead to scaling laws for their respective contributions to the overall NOsb{x} emissions performance. It is found that the relative importance of each source depends on the burner scale and operating conditions. Simple furnace residence time scaling is shown to be largely irrelevant, with NOsb{x} emissions instead being largely controlled by scaling of the near-burner region. The scalings for these NOsb{x} sources are combined in a comprehensive scaling model for NOsb{x} emission performance. Results from the scaling model show good agreement with experimental data at all burner scales and over the entire range of turndown, staging, preheat, and excess air dilution, with correlations generally exceeding 90%. The scaling model permits design trade-off assessments for a broad class of burners and furnaces, and allows performance of full industrial scale burners and furnaces of this type to be inferred from results of small scale tests.

Optimization of burners in oxygen-gas fired glass furnace

NARCIS (Netherlands)

Kersbergen, M.J. van; Beerkens, R.G.C.; Sarmiento-Darkin, W.; Kobayashi, H.

2012-01-01

The energy efficiency performance, production stability and emissions of oxygen-fired glass furnaces are influenced by the type of burner, burner nozzle sizes, burner positions, burner settings, oxygen-gas ratios and the fuel distribution among all the burners. These parameters have been optimized

Southern Woods-Burners: A Descriptive Analysis

Science.gov (United States)

M.L. Doolittle; M.L. Lightsey

1979-01-01

About 40 percent of the South's nearly 60,000 wildfires yearly are set by woods-burners. A survey of 14 problem areas in four southern States found three distinct sets of woods-burners. Most active woods-burners are young, white males whose activities are supported by their peers. An older but less active group have probably retired from active participation but...

Case study for co and counter swirling domestic burners

Directory of Open Access Journals (Sweden)

Ashraf Kotb

2018-03-01

Full Text Available In this case study, the influence of equivalence ratio for co and counter-swirl domestic burners compared with non-swirl design on the thermal efficiency as well as CO emissions has been studied using liquefied petroleum gas (LPG. Also, the flame stability, and pot height, which is defined as the burner-to-pot distance (H, of the co and counter domestic burners were compared. The analysis of the results showed that, for both swirl burners co and counter one the thermal efficiency under all operation conditions tested is higher than the non-swirled burner (base burner. For example, the thermal efficiency increased by 8.8%, and 5.8% than base burner for co and counter swirl, respectively at Reynolds number equal 2000 and equivalence ratio 1. The co and counter swirl burners show lower CO emission than the base burner. The co swirl burner has wider operation range than counter swirl. With the increase of pot height, the thermal efficiency of all burners decreases because the flame and combustion gases are cooled due to mixing with ambient air. As a result, the heat transfer is decreased due to atmospheric loss, which decrease the thermal efficiency.

DESIGN AND DEVELOPMENT OF MILD COMBUSTION BURNER

Directory of Open Access Journals (Sweden)

M.M. Noor

2013-12-01

Full Text Available This paper discusses the design and development of the Moderate and Intense Low oxygen Dilution (MILD combustion burner using Computational Fluid Dynamics (CFD simulations. The CFD commercial package was used to simulate preliminary designs for the burner before the final design was sent to the workshop for fabrication. The burner is required to be a non-premixed and open burner. To capture and use the exhaust gas, the burner was enclosed within a large circular shaped wall with an opening at the top. An external EGR pipe was used to transport the exhaust gas which was mixed with the fresh oxidant. To control the EGR and exhaust flow, butterfly valves were installed at the top opening as a damper to close the exhaust gas flow at a certain ratio for EGR and exhaust out to the atmosphere. High temperature fused silica glass windows were installed to view and capture images of the flame and analyze the flame propagation. The burner simulation shows that MILD combustion was achieved for the oxygen mole fraction of 3-13%. The final design of the burner was fabricated and ready for the experimental validation.

CBAS - efficient coal management for optimised operation and minimised cost; CBAS - Betriebsoptimierung und Kostenminimierung durch effizientes Kohlenmanagement

Energy Technology Data Exchange (ETDEWEB)

Pechtl, P.; Petek, J.; Shea, S.

2000-07-01

The 'Coal Bland Automation System' CBAS developed by Praxis Engineers, Inc. is a software application which simulates the path of coal from the dispatching station to the burners. The combustion characteristics of coal mixtures are predicted, and the fuel quality can be controlled hours before the coal arrives at the burners. Detailed modelling of the flow patterns in the mixing bunkers and grinding bunkers, time variations of the coal mixture properties at the bunker outlet can be predicted, and the coal mixture can be varied accordingly to account for load peaks. [German] Das von Praxis Engineers, Inc. entwickelte 'Coal Bland Automation System' CBAS ist eine online Softwareapplikation, die den Weg aller in einem Kraftwerk eingesetzten Kohlensorten vom Verladeplatz bis hin zu den Brennern mathematisch simuliert. Die Eigenschaften beliebiger Mischungen zwischen den Kohlen werden vorausgesagt und die Qualitaet des Brennstoffs an den Brennern kann geregelt werden, auch Stunden bevor die Kohlenmischung tatsaechlich an den Brennern ankommt. Aufgrund der detaillierten Modellierung des Fliessverhaltens in den Mischbunkern und den Bunkern der Kohlemuehlen ist es moeglich, die zeitliche Veraenderung der Eigenschaften der Kohlenmischung am Austritt aus den Bunkern vorherzusagen. Dadurch kann das Mischungsverhaeltnis der Kohlen rascher an die Lastanforderungen angepasst werden, was z.B. zum 'Einfangen' von lukrativen Lastspitzen genutzt werden kann. (orig.)

Return to coal at the Champagne Soise power station

Energy Technology Data Exchange (ETDEWEB)

Feger, M

1981-03-01

This power station, which comprises two 250 MW units, which came on stream in 1961 and 1965, burned coal until 1970 and fuel oil until 1977 when it was decided to revert to coal. The author describes the work and modifications carried out for this purpose: internal changes to the boilers and burners, to the coal handling and crushing arrangements and overhauling of the de-dusters and auxiliary circuits. Gives details of the organization and planning of the work involved, plus costs and distribution of expenditure. Gives the operating results and concludes that the reconversion costs were paid off within the year. (In French)

Raising the Reliability, Efficiency, and Ecological Safety of Operation of the BKZ-210-140F Boiler Transferred to Stage Firing of Kuznetsk Coal in a U-Shape Flame

International Nuclear Information System (INIS)

Vagner, A. A.

2004-01-01

The BKZ-210-140F boiler of the West-Siberian Cogeneration Plant was equipped initially with four uniflow tangentially oriented burners and tertiary air nozzles. In order to raise the efficiency of operation and lower harmful emissions the boiler was reconstructed. U-shape aerodynamics was organized in the furnace by mounting 8 burners, 8 secondary air nozzles, and 8 tertiary air nozzles on the front and rear walls of the furnace. The reconstruction ensured higher stability of ignition of pulverized coal without flame division and rated temperatures of the superheater metal, lowered the optimum excess air factor at the outlet from the superheater to 1.2 - 1.25, decreased the concentration of nitrogen oxides in the combustion products to 360 - 380 mg/m 3 , and increased the gross efficiency of the boiler to 91.5 - 91.7%

The new low-NO{sub x} burner

Energy Technology Data Exchange (ETDEWEB)

Saito, Masato [Joban Joint Power Corporation, Ltd., Nagasaki (Japan); Domoto, Kazuhiro; Tanaka, Ryuichiro [Mitsubishi Heavy Industries, Ltd., Nagasaki (Japan). Boiler Engineering Dept. Power Systems; Matsumoto, Keigo [Mitsubishi Heavy Industries, Ltd., Nagasaki (Japan). Combustion Lab.

2013-11-01

Burner design requires good ignitability, high burn-up rate and low NO{sub x} emissions. Mitsubishi Heavy Industries Ltd. (MHI) developed a low-NO{sub x} burner which meets the aforementioned requirements. It also needs less combustion air, the burner nozzle is subjected to less thermal stresses, and the potential of NO{sub x} corrosion is being reduced. (orig.)

IEA low NOx combustion project Stage III. Low NOx combustion and sorbent injection demonstration projects. V.2

International Nuclear Information System (INIS)

Payne, R.

1991-03-01

This report summarizes the main results from an IES project concerning the demonstration of low-NO x combustion and sorbent injection as techniques for the control of NO x and SO x emissions from pulverized coal fired utility boilers. The project has built upon information generated in two previous stages of activity, where NO x and SO x control processes were evaluated at both fundamental and pilot-scales. The concept for this stage of the project was for a unique collaboration, where the participating countries (Canada, Denmark and Sweden, together with the United States) have pooled information from full scale boiler demonstrations of low-NO x burner and sorbent injection technologies, and have jointly contributed to establishing a common basis for data evaluation. Demonstration testing was successfully carried out on five wall-fired commercial boiler systems which ranged in size from a 20 MW thermal input boiler used for district heating, up to a 300 MW electric utility boiler. All of these units were fired on high-volatile bituminous coals with sulfur contents ranging from 0.6-3.2 percent. At each site the existing burners were either modified or replaced to provide for low-NO x combustion, and provisions were made to inject calcium based sorbent materials into the furnace space for SO 2 emission control. The results of sorbent injection testing showed moderate levels of SO 2 removal which ranged from approximately 15 to 55 percent at an injected calcium to sulfur molar ratio to 2.0 and with boiler operation at nominal full load. Sulfur capture was found to depend upon the combined effects of parameters such as: sorbent type and reactivity; peak sorbent temperature; coal sulfur content; and the thermal characteristics of the boilers. (8 refs., 58 figs., 6 tabs.)

DESIGN REPORT: LOW-NOX BURNERS FOR PACKAGE BOILERS

Science.gov (United States)

The report describes a low-NOx burner design, presented for residual-oil-fired industrial boilers and boilers cofiring conventional fuels and nitrated hazardous wastes. The burner offers lower NOx emission levels for these applications than conventional commercial burners. The bu...

Aspects on prediction of two-phase reacting flow in a swirl-stabilized pulverized coal flame

Energy Technology Data Exchange (ETDEWEB)

Wennerberg, D. (LSTM, Erlangen (Germany))

1991-01-01

Knowledge of NO{sub x} formation routes in a pulverized coal flame is essential for understanding the problematics. Coal-bound N is the dominated source of NO{sub x} in a pf flame. The so-called 'thermal' NO{sub x} plays a minor role, since the temperature level is lower in a pf flame than in a gas - or oilfired flame. The coalbound N is mainly released along with the volatiles in the coal as HCN. This release takes place in the central recirculation zone when the coal is first heated up. The continued reaction processes of the HCN take different paths, dependent on whether the burner near field zone is fuel-rich or fuel-lean: Under fuel-rich conditions: HCN {yields} CN {yields} N{sub 2}. Under fuel-lean conditions: HCN {yields} NH/NCO {yields} NO. This reaction scheme is strongly simplified in order to clarify the main influence of the aerodynamics on the NO{sub x} formation. Concentration of radicals O, OH, H are also important for the reaction routes as well as the residence time for the coal particles under respective conditions. The conditions for reactions are however determined largely by the aerodynamics of the near-field burner zone. (orig./GL).

Research on the Improvement of a Natural Gas Fired Burner for the CHP Application in a Central Heating Boiler using Radiant Burner Technology

Energy Technology Data Exchange (ETDEWEB)

Bieleveld, T.

2010-08-15

These days, the reduction of CO2 emissions from combustion devices is one of the main priorities for each design improvement. For the domestic use of the central heating boiler, Microgen Engine Corporation produces free piston Stirling engines for the Combined Heat and Power (CHP) application in these central heating boilers (Dutch: 'HRe ketel'). With CHP, the generation of electricity and heat are combined to increase overall efficiency, as heat is generally a waste product from the combustion to electric generation process. In this application, the Stirling engine, which can be defined as an external combustion engine, is heated by a natural gas fired engine-burner and cooled by a coolant flow. The heat transfer into the engine is converted into mechanical work and a heat flux from the engine. The mechanical work is used to produce electricity via a linear alternator. Heat in the flue gasses from the engine-burner is reused in a secondary burner and condensing heat exchanger. The coolant flow from the engine, after passing the secondary burner, is used for heating purposes. The heat transfer from engine-burner to the Stirling engine is analyzed and via several motivations it is found that it is favorable to improve fuel to electric conversion efficiency, for which the heat transfer efficiency of the engine-burner to the Stirling engine should be improved, as the engine design is not to be altered. From an initially developed linear free piston Stirling engine model and measurements performed at Microgen Engine Corporation, St. Petersborough, (UK), the engine power demand and engine-burner performance are found. The results are used to visualize the current energy flows of the Stirling engine and engine burner subsystem. The heat transfer to the engine is analyzed to find possible heat transfer improvements. It is concluded that heat transfer from the engine-burner to the engine can be approved if the flue losses due to convective heat transfer are

Coal 95

International Nuclear Information System (INIS)

Sparre, C.

1995-01-01

The report deals with the use of coal and coke in Sweden during 1994. Some information about technology, environmental questions and markets are also given. Data have been collected by questionnaires to major users and by telephone to minor users. Preliminary statistical data from Statistics Sweden have also been used.The use of steam coal for heating purposes has been unchanged during 1994 at a level of 1 Mtons. The production in the cogeneration plants has been constant, but has increased for electricity production. The minor plants have increased their use of forest fuels. The use of steam coal will probably go down in the next years both for heat and cogeneration plants. During the top year 1987 coal was used in 18 hot water and 11 cogeneration plants. 1994 these figures are 3 and 12. Taxes and environmental reasons explain this trend. The use of steam coal in industry has been constant at the level 0.7 Mtons. The import of metallurgical coal in 1993 was 1.6 Mtons, like 1992. Import of 0.3 Mtons of coke gives the total consumption of coke in industry as 1.5 Mtons. the average price of steam coal imported to Sweden was 317 SEK/ton, 3% higher than 1993. All Swedish plants meet their emission limit of dust, SO 2 and NO x as given by county administrations or concession boards. The cogeneration plants all have some SO 2 removal system. The biggest cogeneration plant (Vaesteraas) has recently invested in a SCR NO x cleaning system. Most other plants use low NO x burners or SNR injection systems based on ammonia or urea. 2 figs, 13 tabs

Development of a pulsed coal combustor fired with CWM (coal-water mixture): Phase 3, Final report

Energy Technology Data Exchange (ETDEWEB)

Mansour, M.N.; Durai-Swamy, K.

1986-11-01

This report presents the results of an R and D program aimed at developing a new burner technology for coal-water mixture (CWM) fuels to enable the substitution of these new fuels in utility and industrial boilers and process heaters currently firing oil and gas. The application of pulse combustion to CWM fuels is chosen to alleviate many of the physical plant and environmental constraints presently associated with the direct use of these fuels in equipment designed for oil and gas firing. Pulse combustion has been shown to be capable of high-intensity burning of coal for acceptably complete combustion within relatively small equipment volumes. It also has the inherent capability to agglomerate ash particles, thus rendering ash more easily separable from the combustion gas prior to its entrance into the convective section of the boiler or heater, thereby reducing ash buildup and pluggage. Pulse combustion is also well-suited to staged combustion for NO/sub x/ control and has excellent potential for enhanced in-furnace SO/sub 2/ removal due to the enhanced levels of mass transfer brought about by the vigorous flow oscillations. The primary objective of the Phase 2 work was to develop a detailed program for laboratory development and evaluation of the pulse CWM combustor and system design concepts. 112 refs., 40 figs., 94 tabs.

Low NO subx heavy fuel combustor concept program. Phase 1A: Coal gas addendum

Science.gov (United States)

Rosfjord, T.; Sederquist, R.

1982-01-01

The performance and emissions from a rich-lean combustor fired on simulated coal gas fuels were investigated using a 12.7-cm diameter axially-staged burner originally designed for operation with high heating value liquid fuels. A simple, tubular fuel injector was substituted for the liquid fuel nozzle; no other combustor modifications were made. Four test fuels were studied including three chemically bound nitrogen-free gas mixtures with higher heating values of 88, 227, and 308 kj/mol (103, 258 and 349 Btu/scf), and a 227 kj/mol (258 Btu/scf) heating value doped with ammonia to produce a fuel nitrogen content of 0.5% (wt). Stable, ultra-low nitrogen oxide, smoke-free combustion was attained for the nitrogen-free fuels. Results with the doped fuel indicated that less than 5% conversion of NH3 to nitrogen oxide levels below Environmental Protection Agency limits could be achieved. In some instances, excessive CO levels were encountered. It is shown that use of a burner design employing a less fuel-rich primary zone than that found optimum for liquid fuels would yield more acceptable CO emissions.

Engineering development of coal-fired high-performance power systems

International Nuclear Information System (INIS)

1998-01-01

A High Performance Power System (HIPPS) is being developed. This system is a coal-fired, combined cycle plant with indirect heating of gas turbine air. Foster Wheeler Development Corporation and a team consisting of Foster Wheeler Energy Corporation, Bechtel Corporation, University of Tennessee Space Institute and Westinghouse Electric Corporation are developing this system. In Phase 1 of the project, a conceptual design of a commercial plant was developed. Technical and economic analyses indicated that the plant would meet the goals of the project which include a 47 percent efficiency (HHV) and a 10 percent lower cost of electricity than an equivalent size PC plant. The concept uses a pyrolyzation process to convert coal into fuel gas and char. The char is fired in a High Temperature Advanced Furnace (HITAF). The HITAF is a pulverized fuel-fired boiler/air heater where steam is generated and gas turbine air is indirectly heated. The fuel gas generated in the pyrolyzer is then used to heat the gas turbine air further before it enters the gas turbine. The project is currently in Phase 2, which includes engineering analysis, laboratory testing and pilot plant testing. Research and development is being done on the HIPPS systems that are not commercial or being developed on other projects. Pilot plant testing of the pyrolyzer subsystem and the char combustion subsystem are being done separately, and after each experimental program has been completed, a larger scale pyrolyzer will be tested at the Power Systems Development Facility (PSDF) in Wilsonville, Al. The facility is equipped with a gas turbine and a topping combustor, and as such, will provide an opportunity to evaluate integrated pyrolyzer and turbine operation. During this quarter, initial char combustion tests were performed at the CETF using a Foster Wheeler commercial burner. These preliminary tests were encouraging and will be used to support the development of an innovative char burner for the HIPPS

Premixed combustion on ceramic foam burners

NARCIS (Netherlands)

Bouma, P.H.; Goey, de L.P.H.

1999-01-01

Combustion of a lean premixed methane–air mixture stabilized on a ceramic foam burner has been studied. The stabilization of the flame in the radiant mode has been simulated using a one-dimensional numerical model for a burner stabilized flat-flame, taking into account the heat transfer between the

Altitude Performance Characteristics of Tail-pipe Burner with Convergingconical Burner Section on J47 Turbojet Engine

Science.gov (United States)

Prince, William R; Mcaulay, John E

1950-01-01

An investigation of turbojet-engine thrust augmentation by means of tail-pipe burning was conducted in the NACA Lewis altitude wind tunnel. Performance data were obtained with a tail-pipe burner having a converging conical burner section installed on an axial-flow-compressor type turbojet engine over a range of simulated flight conditions and tail-pipe fuel-air ratios with a fixed-area exhaust nozzle. A maximum tail-pipe combustion efficiency of 0.86 was obtained at an altitude of 15,000 feet and a flight Mach number of 0.23. Tail-pipe burner operation was possible up to an altitude of 45,000 feet at a flight Mach number of 0.23.

Numerical Simulation of Gas-Solid Two-Phase Flow for Four-Channels Pulverized Swirling Burner

Directory of Open Access Journals (Sweden)

Defu LI

2013-05-01

Full Text Available This article presents a mathematical model of cold gas-solid two-phase flow which is based on the cement rotary kiln in service. By altering the parameters of air supply system of four- channels pulverized burner, investigations are taken of that motion trajectory and particle distributions in the very turbulent field. The results show that motion trail of most particles in rotary kiln is a combination process of gradual diffusion and slow sedimentation; increasing internal flow velocity would aggravate coal particles to diffuse; external flow velocity should be controlled in a reasonable range.

Innovative Clean Coal Technology (ICCT): 500-MW demonstration of advanced wall-fired cmbustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. Field chemical emissions monitoring, Overfire air and overfire air/low NO{sub x} burner operation: Final report

Energy Technology Data Exchange (ETDEWEB)

NONE

1993-12-31

This report summarizes data gathered by Radian Corporation at a coal-fired power plant, designated Site 16, for a program sponsored by the United States Department of Energy (DOE), Southern Company Services (SCS), and the Electric Power Research Institute (EPRI). Concentrations of selected inorganic and organic substances were measured in the process and discharge streams of the plant operating under two different types of combustion modifications: overfire air (OFA) and a combination of overfire air with low-NO{sub x} burners (OFA/LNB). Information contained in this report will allow DOE and EPRI to determine the effects of low-NO{sub x} modifications on plant emissions and discharges. Sampling was performed on an opposed wall-fired boiler burning medium-sulfur bituminous coal. Emissions were controlled by electrostatic precipitators (ESPs). The testing was conducted in two distinct sampling periods, with the OFA test performed in March of 1991 and the OFA/LNB test performed in May of 1993. Specific objectives were: to quantify emissions of target substances from the stack; to determine the efficiency of the ESPs for removing the target substances; and to determine the fate of target substances in the various plant discharge streams.

DEMONSTRATION OF SORBENT INJECTION TECHNOLOGY ON A TANGENTIALLY COAL-FIRED UTILITY BOILER (YORKTOWN LIMB DEMONSTRATION)

Science.gov (United States)

The report summarizes activities conducted and results achieved in an EPA-sponsored program to demonstrate Limestone Injection Multistage Burner (LIMB) technology on a tangentially fired coal-burning utility boiler, Virginia Power's 180-MWe Yorktown Unit No. 2. his successfully d...

Minor actinide transmutation using minor actinide burner reactors

International Nuclear Information System (INIS)

Mukaiyama, T.; Yoshida, H.; Gunji, Y.

1991-01-01

The concept of minor actinide burner reactor is proposed as an efficient way to transmute long-lived minor actinides in order to ease the burden of high-level radioactive waste disposal problem. Conceptual design study of minor actinide burner reactors was performed to obtain a reactor model with very hard neutron spectrum and very high neutron flux in which minor actinides can be fissioned efficiently. Two models of burner reactors were obtained, one with metal fuel core and the other with particle fuel core. Minor actinide transmutation by the actinide burner reactors is compared with that by power reactors from both the reactor physics and fuel cycle facilities view point. (author)

Porosity effects in flame length of the porous burners

Directory of Open Access Journals (Sweden)

Fatemeh Bahadori

2014-10-01

Full Text Available Furnaces are the devices for providing heat to the industrial systems like boilers, gas turbines and etc. The main challenge of furnaces is emission of huge air pollutants. However, porous burners produce less contaminant compared to others. The quality of the combustion process in the porous burners depends on the length of flame in the porous medium. In this paper, the computational fluid dynamic (CFD is used to investigate the porosity effects on the flame length of the combustion process in porous burner. The simulation results demonstrate that increasing the porosity increases the flame length and the combustion zone extends forward. So, combustion quality increases and production of carbon monoxide decrease. It is possible to conclude that temperature distribution in low porosity burner is lower and more uniform than high porosity one. Therefore, by increasing the porosity of the burner, the production of nitrogen oxides increases. So, using an intermediate porosity in the burner appears to be reasonable.

Numerical study of flow, combustion and emissions characteristics in a 625 MWe tangentially fired boiler with composition of coal 70% LRC and 30% MRC

Science.gov (United States)

Sa'adiyah, Devy; Bangga, Galih; Widodo, Wawan; Ikhwan, Nur

2017-08-01

Tangential fired boiler is one of the methods that can produce more complete combustion. This method applied in Suralaya Power Plant, Indonesia. However, the boiler where supposed to use low rank coal (LRC), but at a given time must be mixed with medium rank coal (MRC) from another unit because of lack of LRC coal. Accordingly to the situation, the study about choosing the right position of LRC and MRC in the burner elevation must be investigated. The composition of coal is 70%LRC / 30%MRC where MRC will be placed at the lower (A & C - Case I)) or higher (E & G - Case II) elevation as the cases in this study. The study is carried out using Computational Fluid Dynamics (CFD) method. The simulation with original case (100%LRC) has a good agreement with the measurement data. As the results, MRC is more recommended at the burner elevation A & C rather than burner elevation E & G because it has closer temperature (880 K) compared with 100%LRC and has smaller local heating area between upper side wall and front wall with the range of temperature 1900 - 2000 K. For emissions, case I has smaller NOx and higher CO2 with 104 ppm and 15,6%. Moreover, it has samller O2 residue with 5,8% due to more complete combustion.

RF torch discharge combined with conventional burner

International Nuclear Information System (INIS)

Janca, J.; Tesar, C.

1996-01-01

The design of the combined flame-rf-plasma reactor and experimental examination of this reactor are presented. For the determination of the temperature in different parts of the combined burner plasma the methods of emission spectroscopy were used. The temperatures measured in the conventional burner reach the maximum temperature 1900 K but in the burner with the superimposed rf discharge the neutral gas temperature substantially increased up to 2600 K but also the plasma volume increases substantially. Consequently, the resident time of reactants in the reaction zone increases

Carbon burnout of pulverised coal in power station furnaces

Energy Technology Data Exchange (ETDEWEB)

R.I. Backreedy; L.M. Fletcher; J.M. Jones; L. Ma; M. Pourkashanian; A. Williams; K. Johnson; D.J. Waldron; P. Stephenson [University of Leeds, Leeds (United Kingdom)

2003-07-01

The degree of carbon burnout in pulverised fuel fired power stations is important because it is linked with power plant efficiency and coal ash suitability for construction purposes. The use of computational methods to calculate carbon burnout in such systems has been aided by the increasing availability of fast computers and improvements in computational methodologies. Despite recent advances in fluid flow, coal devolatilisation and coal combustion models, the use of CFD methods for detailed design purposes or for the selection of commercial coals is still limited. In parallel, industrial engineering codes, which combine simplified thermal models with advanced coal combustion models, are still undergoing development since they provide economic advantages over detailed CFD analysis. Although the major coal combustion processes are well established, an understanding regarding the role of coal macerals and the influence of ash on the combustion process is still lacking. A successful coal model must be able to handle all the complexities of combustion, from the details of the burner geometry through to the formation of unburnt carbon as well as NOx. The development of such a model is described here.

Evaluation of NOX emissions from TVA coal-fired power plants

International Nuclear Information System (INIS)

Jones, J.W.; Stamey-Hall, S.

1991-01-01

The paper gives results of a preliminary evaluation of nitrogen oxide (NOx) emissions from 11 Tennessee Valley Authority (TVA) coal-fired power plants. Current EPA AP-42 emission factors for NOx from coal-fired utility boilers do not account for variations either in these emissions as a function of generating unit load, or in designs of boilers of the same general type, particularly wall-fired boilers. The TVA has compiled short-term NOx emissions data from 30 units at 11 TVA coal-fired plants. These units include cyclone, cell burner, single wall, opposed wall, single tangential, and twin tangential boiler firing designs. Tests were conducted on 29 of the 30 units at high load; 18 were also tested at reduced load. NOx emissions rates were calculated for each test and compared to the calculated rate for each boiler type using AP-42. Preliminary analysis indicates that: (1) TVA cyclone-fired units emit more NOx than estimated using AP-42; (2) TVA cell burner units emit considerably more NOx than estimated; (3) most TVA single-wall-fired units emit slightly more NOx than estimated; (4) most TVA single-furnace tangentially fired units emit less NOx than estimated at high load, but the same as (or more than) estimated at reduced load; and (5) most TVA twin-furnace tangentially fired units, at high load, emit slightly more NOx than estimated using AP-42

Results of Study of Sulfur Oxide Reduction During Combustion of Coal-Water Slurry Fuel Through use of Sulfur Capturing Agents

Directory of Open Access Journals (Sweden)

Murko Vasiliy I.

2016-01-01

Full Text Available It is shown that an effective way of burning high sulfur coal is to burn coal-water slurry fuel (CWF prepared on its basis containing a sulfur capture agent (SCA entered in the slurry at the stage of preparation. The technique of thermodynamic analysis of chemical reactions during CWF burning has been developed including burning in the presence of SCA. Using the developed calculation program, the optimal temperature conditions have been determined as required for the effective reduction of sulfur oxides in flue gases when using different types of SCA. According to the results of calculating the composition of CWF combustion products when entering various substances in the burner space as SCA it has been determined that magnesite, calcite, and dolomite are the most effective natural minerals. The analysis of calculated and experimental data proves the efficiency of SCA addition as well as validity of the obtained results.

Efficient industrial burner control of a flexible burner management system; Effiziente industrielle Brennertechnik durch Einsatz flexibler Feuerungsautomaten

Energy Technology Data Exchange (ETDEWEB)

Hofmann, Ulrich; Saenger, Peter [Siemens AG, Rastatt (Germany)

2012-02-15

Compactness and flexibility of a burner control system is a very important issue. With a few types a wide range in different industrial applications should be covered. This paper presents different applications of a new burner control system: heating of cooling lines in glass industry, steam generation and air heating for a pistachio roastery and in grain dryers. (orig.)

CHP Integrated with Burners for Packaged Boilers

Energy Technology Data Exchange (ETDEWEB)

Castaldini, Carlo; Darby, Eric

2013-09-30

The objective of this project was to engineer, design, fabricate, and field demonstrate a Boiler Burner Energy System Technology (BBEST) that integrates a low-cost, clean burning, gas-fired simple-cycle (unrecuperated) 100 kWe (net) microturbine (SCMT) with a new ultra low-NOx gas-fired burner (ULNB) into one compact Combined Heat and Power (CHP) product that can be retrofit on new and existing industrial and commercial boilers in place of conventional burners. The Scope of Work for this project was segmented into two principal phases: (Phase I) Hardware development, assembly and pre-test and (Phase II) Field installation and demonstration testing. Phase I was divided into five technical tasks (Task 2 to 6). These tasks covered the engineering, design, fabrication, testing and optimization of each key component of the CHP system principally, ULNB, SCMT, assembly BBEST CHP package, and integrated controls. Phase I work culminated with the laboratory testing of the completed BBEST assembly prior to shipment for field installation and demonstration. Phase II consisted of two remaining technical tasks (Task 7 and 8), which focused on the installation, startup, and field verification tests at a pre-selected industrial plant to document performance and attainment of all project objectives. Technical direction and administration was under the management of CMCE, Inc. Altex Technologies Corporation lead the design, assembly and testing of the system. Field demonstration was supported by Leva Energy, the commercialization firm founded by executives at CMCE and Altex. Leva Energy has applied for patent protection on the BBEST process under the trade name of Power Burner and holds the license for the burner currently used in the product. The commercial term Power Burner is used throughout this report to refer to the BBEST technology proposed for this project. The project was co-funded by the California Energy Commission and the Southern California Gas Company (SCG), a

Studying the melting behavior of coal, biomass, and coal/biomass ash using viscosity and heated stage XRD data

DEFF Research Database (Denmark)

Arvelakis, Stelios; Folkedahl, B.; Dam-Johansen, Kim

2006-01-01

by the cocombustion tests appeared to be somewhat different compared to that of the laboratory-prepared ash samples. The heated stage XRD data provide useful information regarding the reactions among the various ash compounds and the phase transformations during the heating and cooling of the ash samples and helped...... a high-temperature rotational viscometer and a hot stage XRD. The produced data were used to calculate the operating temperature of a pilot-scale entrained flow reactor during the cocombustion of biomass/ coal samples in order to ensure the slag flow and to avoid corrosion of the walls due to liquid slag...

Burner for a wood burning furnace

Energy Technology Data Exchange (ETDEWEB)

Nolting, H

1981-12-10

The burner according to the invention consists of a horizontal tube, whose front wall is penetrated by an intake pipe, which is surrounded by a pipe duct and several divided shells, which are arranged below the pipe duct. The front wall is also provided with air openings. The intake pipe is provided with a spiral and moves chopped wood into the burner.

OPTIMIZED FUEL INJECTOR DESIGN FOR MAXIMUM IN-FURNACE NOx REDUCTION AND MINIMUM UNBURNED CARBON

Energy Technology Data Exchange (ETDEWEB)

SAROFIM, A F; LISAUSKAS, R; RILEY, D; EDDINGS, E G; BROUWER, J; KLEWICKI, J P; DAVIS, K A; BOCKELIE, M J; HEAP, M P; PERSHING, D

1998-01-01

Reaction Engineering International (REI) has established a project team of experts to develop a technology for combustion systems which will minimize NO x emissions and minimize carbon in the fly ash. This much need technology will allow users to meet environmental compliance and produce a saleable by-product. This study is concerned with the NO x control technology of choice for pulverized coal fired boilers,"in-furnace NO_x control," which includes: staged low-NO_x burners, reburning, selective non-catalytic reduction (SNCR) and hybrid approaches (e.g., reburning with SNCR). The program has two primary objectives: 1) To improve the performance of "in-furnace" NO_x control, processes. 2) To devise new, or improve existing, approaches for maximum "in-furnace" NO_x control and minimum unburned carbon. The program involves: 1) fundamental studies at laboratory- and bench-scale to define NO reduction mechanisms in flames and reburning jets; 2) laboratory experiments and computer modeling to improve our two-phase mixing predictive capability; 3) evaluation of commercial low-NO_x burner fuel injectors to develop improved designs, and 4) demonstration of coal injectors for reburning and low-NO_x burners at commercial scale. The specific objectives of the two-phase program are to: 1 Conduct research to better understand the interaction of heterogeneous chemistry and two phase mixing on NO reduction processes in pulverized coal combustion. 2 Improve our ability to predict combusting coal jets by verifying two phase mixing models under conditions that simulate the near field of low-NO_x burners. 3 Determine the limits on NO control by in-furnace NO_x control technologies as a function of furnace design and coal type. 5 Develop and demonstrate improved coal injector designs for commercial low-NO_x burners and coal reburning systems. 6 Modify the char burnout model in REI's coal

Evaluating the efficacy of a minor actinide burner

International Nuclear Information System (INIS)

Dobbin, K.D.; Kessler, S.F.; Nelson, J.V.; Omberg, R.P.; Wootan, D.W.

1993-06-01

The efficacy of a minor actinide burner can be evaluated by comparing safety and economic parameters to the support ratio. Minor actinide mass produced per unit time in this number of Light Water Reactors (LWRs) can be burned during the same time period in one burner system. The larger the support ratio for a given set of safety and economic parameters, the better. To illustrate this concept, the support ratio for selected Liquid Metal Reactor (LMR) burner core designs was compared with corresponding coolant void worths, a fundamental safety concern following the Chernobyl accident. Results can be used to evaluate the cost in reduced burning of minor actinides caused by LMR sodium void reduction efforts or to compare with other minor actinide burner systems

Effect of primary air content on formation of nitrogen oxides during combustion of Ehkibastuz coal

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R.; Imankulov, Eh.R.

1986-01-01

Investigations are discussed carried out in a pilot plant at the Kaz. Power Engineering Scientific Research Institute into the effect of the amount of primary air in coal-dust flame on the final concentration of nitrogen oxides in flue gases. The tests were carried out in a 7500 mm high, 1600 mm dia vertical cylindrical combustion chamber having type P-57 burner, and air dispersed fuel plus additional air supplies located at the top. Amounts of coal dust fed by a drum feeder along the air pipe varied from 100-600 kg/h. The required air was supplied by 5000 m/sup 3//h Type TK-700/5 blowers at 0.04 MPa. Ehkibastuz coal samples contained: 1.3% moisture; 48.1% ash; 38.02% carbon; 2.56% hydrogen; 0.73% sulfur; 0.60% nitrogen; heat of combustion was 14.3 MJ/kg. Results obtained indicate that variations in the amount of primary air in swirl flow burners affect formation of fuel nitrogen; there is an optimum volume at which minimum quantities of nitrogen oxides are formed. Either an increase or decrease in the primary air results in a rise in nitrogen oxide concentration. 3 references.

0.20-m (8-in.) primary burner development report

International Nuclear Information System (INIS)

Stula, R.T.; Young, D.T.; Rode, J.S.

1977-12-01

High-Temperature Gas-Cooled Reactors (HTGRs) utilize graphite-base fuels. Fluidized-bed burners are being employed successfully in the experimental reprocessing of these fuels. The primary fluidized-bed burner is a unit operation in the reprocessing flowsheet in which the graphite moderator is removed. A detailed description of the development status of the 0.20-m (8-in.) diameter primary fluidized-bed burner as of July 1, 1977 is presented. Experimental work to date performed in 0.10; 0.20; and 0.40-m (4, 8, and 16 in.) diameter primary burners has demonstrated the feasibility of the primary burning process and, at the same time, has defined more clearly the areas in which additional experimental work is required. The design and recent operating history of the 0.20-m-diameter burner are discussed, with emphasis placed upon the evolution of the current design and operating philosophy

Study of initial stage in coal liquefaction. Increase in oil yield with suppression of retrogressive reaction during initial stage; Ekika hanno no shoki katei ni kansuru kenkyu. 1.

Energy Technology Data Exchange (ETDEWEB)

Uesugi, K.; Kanaji, M.; Kaneko, T.; Shimasaki, K. [Nippon Brown Coal Liquefaction Co. Ltd., Tokyo (Japan)

1996-10-28

For the coal liquefaction, improvement of liquefaction conditions and increase of liquefied oil yield are expected by suppressing the recombination through rapid stabilization of pyrolytic radicals which are formed at the initial stage of liquefaction. Two-stage liquefaction combining prethermal treatment and liquefaction was performed under various conditions, to investigate the effects of reaction conditions on the yields and properties of products as well as to increase liquefied oil yield. Consequently, it was found that the catalyst contributes greatly to the hydrogen transfer to coal at the prethermal treatment. High yield of n-hexane soluble fraction with products having low condensation degree could be obtained by combining the prethermal treatment in the presence of hydrogen and catalyst with the concentration of slurry after the treatment. This was considered to be caused by the synergetic effect between the improvement of liquefaction by suppressing polymerization/condensation at the initial stage of reaction through the prethermal treatment and the effective hydrogen transfer accompanied with the improvement of contact efficiency of coal/catalyst by the concentration of slurry at the stage of liquefaction. 4 refs., 8 figs.

Industrial Application of an Improved Multiple Injection and Multiple Staging Combustion Technology in a 600 MWe Supercritical Down-Fired Boiler.

Science.gov (United States)

Song, Minhang; Zeng, Lingyan; Chen, Zhichao; Li, Zhengqi; Zhu, Qunyi; Kuang, Min

2016-02-02

To solve the water wall overheating in lower furnace, and further reduce NOx emissions and carbon in fly ash, continuous improvement of the previously proposed multiple injection and multiple staging combustion (MIMSC) technology lies on three aspects: (1) along the furnace arch breadth, changing the previously centralized 12 burner groups into a more uniform pattern with 24 burners; (2) increasing the mass ratio of pulverized coal in fuel-rich flow to that in fuel-lean flow from 6:4 to 9:1; (3) reducing the arch-air momentum by 23% and increasing the tertiary-air momentum by 24%. Industrial-size measurements (i.e., adjusting overfire air (OFA) damper opening of 20-70%) uncovered that, compared with the prior MIMSC technology, the ignition distance of fuel-rich coal/air flow shortened by around 1 m. The gas temperature in the lower furnace was symmetric and higher, the flame kernel moved upward and therefore made the temperature in near-wall region of furnace hopper decrease by about 400 °C, the water wall overheating disappeared completely. Under the optimal OFA damper opening (i.e, 55%), NOx emissions and carbon in fly ash attained levels of 589 mg/m(3) at 6% O2 and 6.18%, respectively, achieving NOx and carbon in fly ash significant reduction by 33% and 37%, respectively.

Study on multi-stage hydropyrolysis of coal in fixed-bed reactor

Energy Technology Data Exchange (ETDEWEB)

Wang, N.; Li, W.; Li, B.-Q. [Chinese Academy of Sciences, Taiyuan (China). State Key Lab of Coal Conversion

1999-07-01

The composition and quantity of the oil in hydropyrolysis (HyPy) and multi-stage HyPy with high and slow heating rate were compared and the effect of multistage HyPy process on desulfurization was investigated. Multistage HyPy of lignite and high sulphur coal were investigated and the effects of residence time, heating rate and pressure on product yields were studied. 6 refs., 4 figs., 2 tabs.

Use of artificial intelligence techniques for optimisation of co-combustion of coal with biomass

Energy Technology Data Exchange (ETDEWEB)

Tan, C.K.; Wilcox, S.J.; Ward, J. [University of Glamorgan, Pontypridd (United Kingdom). Division of Mechanical Engineering

2006-03-15

The optimisation of burner operation in conventional pulverised-coal-fired boilers for co-combustion applications represents a significant challenge This paper describes a strategic framework in which Artificial Intelligence (AI) techniques can be applied to solve such an optimisation problem. The effectiveness of the proposed system is demonstrated by a case study that simulates the co-combustion of coal with sewage sludge in a 500-kW pilot-scale combustion rig equipped with a swirl stabilised low-NOx burner. A series of Computational Fluid Dynamics (CFD) simulations were performed to generate data for different operating conditions, which were then used to train several Artificial Neural Networks (ANNs) to predict the co-combustion performance. Once trained, the ANNs were able to make estimations of unseen situations in a fraction of the time taken by the CFD simulation. Consequently, the networks were capable of representing the underlying physics of the CFD models and could be executed efficiently for a large number of iterations as required by optimisation techniques based on Evolutionary Algorithms (EAs). Four operating parameters of the burner, namely the swirl angles and flow rates of the secondary and tertiary combustion air were optimised with the objective of minimising the NOx and CO emissions as well as the unburned carbon at the furnace exit. The results suggest that ANNs combined with EAs provide a useful tool for optimising co-combustion processes.

Design and construction of an air inductor burner

International Nuclear Information System (INIS)

Martinez, Camilo; Cardona, Mario; Arrieta, Andres Amell

2001-01-01

This article presents research results performed with the purpose of obtain design parameters, construction, and air inductor burner operation, which are used in industrial combustion systems, in several processes such as: metal fusion (fusion furnaces), fluids heating (immerse heating tubes), steam production (steam boiler), drying processes, etc. In order to achieve such objectives, a prototype with thermal power modulation from 6 to 52 kW, was built to be either operated with natural gas or with LPG. The burner was built taking in mind the know how (design procedure) developed according to theoretical schemes of different bibliographic references and knowledge of the research group in gas science and technology of the University of Antioquia. However, with such procedure only the burner mixer is dimensioned and five parameters must to be selected by the designer: burner thermal power, primary aeration ratio, counter pressure at combustion chamber, air pressure admission and gas fuel intended to use. For head design we took in mind research done before by the group of science and technology in gas research: Mono port and bar burner heads with their respective stabilization flame systems

Studies on a burner used biomass pellets as fuel. Performance of a spiral vortex pellet burner

Energy Technology Data Exchange (ETDEWEB)

Iwao, Toshio

1987-12-21

In order to develop a small size burner with high performance using biomass pellets fuel substitute for fuel oil, the burning performance of a spiral vortex pallet burner has been studied. An experimental equipment for the pellet burning is made up of a fuel supply unit, combustion chamber and a furnace. The used woody pellet is made of mixed sawdust and bark; with water content of 10.29%, particle diameter of 5.5-9mm, length of 5-50mm, and, apparent and real specific gravities are 0.59 and 1.334 respectively. The pellets are sent to bottom of the combustion chamber, spiral vortex combustion are carried out with blown air, the ashes and unburnt residues are discharged to out of combustion chamber with spiral vortex hot gases. As the result, it was clarified that the formation of the burning layers in a burner is required to be in order of the layers of ash, oxidation, reduction and carbonization up to the upper layer for high burning performance, and the formation of the layer is influenced by the condition of sedimentation of pellets in the combustion chamber. In the meanwhile the burning performance of the burner is influenced by the quantity of blast, the rate of feeding, and by the time of pre-heating in the combustion chamber. (23 figs, 5 refs)

Process analysis and mechanism of multi-stage hydropyrolysis of coal

Energy Technology Data Exchange (ETDEWEB)

Li, W.; Wang, N.; Li, B.Q. [Chinese Academy of Science, Taiyuan (China). Inst. of Coal Chemistry, State Key Laboratory of Coal Conversion

2002-07-01

The mechanism of multi-stage hydropyrolysis of coal was probed through detailed analysis of products of hydropyrolysis with different holding methods. The results showed that the holding method significantly affects the product distributions, thus making an apparent difference in hydrogen utilization efficiency. The holding temperature should be about 350-500{degree}C during which more free radicals are produced rapidly. Pore-riched structures are formed at the holding stage at 350{degree}C due to the evolution of large amount of volatiles, which is favorable to the subsequent hydrogenation reaction. The holding at a low temperature favors the reaction of hydrogen with oxygen-containing groups, leading to the formation of phenol and avoiding the formation of water at a high temperature. The cleavage of chemical bonds in the char is mainly dependent-on the pyrolysis temperature. The effect of holding stage is to change the distribution and components of products via stabilizing the free radicals and hydrogenating the heavier products.

Multifuel burners based on the porous burner technology for the application in fuel cell systems; Mehrstofffaehige Brenner auf Basis der Porenbrennertechnik fuer den Einsatz in Brennstoffzellensystemen

Energy Technology Data Exchange (ETDEWEB)

Diezinger, S.

2006-07-01

The present doctoral thesis describes the development of multifuel burners based on the porous burner technology for the application in hydrocarbon driven fuel cell systems. One objective of such burners is the heating of the fuel cell system to the operating temperature at the cold start. In stationary operation the burner has to postcombust the waste gases from the fuel cell and the gas processing system in order to reduce the pollutant emissions. As the produced heat is required for endothermal processes like the steam reforming the burner has a significant influence on the system's efficiency. The performed investigations are targeting on a gasoline driven PEMFC-System with steam reforming. In such systems the burner has to be capable to combust the system's fuel gasoline at the cold start, a low calorific fuel cell offgas (HU = 6,4 MJ/kg) in stationary operation and a hydrogen rich gas in the case of an emergency shut down. Pre-tests revealed that in state of the art porous burners the flame front of hydrogen/air combustion can only be stabilized at very high excess air ratios. In basic investigations concerning the stabilization of flame fronts in porous media the dominant influence parameters were determined. Based on this findings a new flame trap was developed which increases the operational range with hydrogen rich mixtures significantly. Furthermore the burning velocity at stationary combustion in porous media was investigated. The dependency of the porous burning velocity on the excess air ratio for different hydrocarbons and hydrogen as well as for mixtures of both was determined. The results of these basic investigations were applied for the design of a multifuel burner. In order to achieve an evaporation of the gasoline without the use of additional energy, an internal heat exchanger section for heating the combustion air was integrated into the burner. Additionally different experimental and numerical methods were applied for designing the

Influence of burner form and pellet type on domestic pellet boiler performance

Science.gov (United States)

Rastvorov, D. V.; Osintsev, K. V.; Toropov, E. V.

2017-10-01

The study presents combustion and emission results obtained using two serial pellet boilers of the same heating capacity 40 kW. These boilers have been designed by producers for domestic conditions of exploitation. The principal difference between boilers was the type of the burner. The study concerns the efficiency and ecological performance difference between burners of circular and rectangular forms. The features of the combustion process in both types of burners were studied when boiler operated with different sorts of pellets. The results suggest that the burner of circular form excels the rectangular form burner. However, there is some difference of NOx emission between circular and rectangular burners.

Advanced char burnout models for the simulation of pulverized coal fired boilers

Energy Technology Data Exchange (ETDEWEB)

T. Severin; S. Wirtz; V. Scherer [Ruhr-University, Bochum (Germany). Institute of Energy Plant Technology (LEAT)

2005-07-01

The numerical simulation of coal combustion processes is widely used as an efficient means to predict burner or system behaviour. In this paper an approach to improve CFD simulations of pulverized coal fired boilers with advanced coal combustion models is presented. In simple coal combustion models, first order Arrhenius rate equations are used for devolatilization and char burnout. The accuracy of such simple models is sufficient for the basic aspects of heat release. The prediction of carbon-in-ash is one aspect of special interest in the simulation of pulverized coal fired boilers. To determine the carbon-in-ash levels in the fly ash of coal fired furnaces, the char burnout model has to be more detailed. It was tested, in how far changing operating conditions affect the carbon-in-ash prediction of the simulation. To run several test cases in a short time, a simplified cellnet model was applied. To use a cellnet model for simulations of pulverized coal fired boilers, it was coupled with a Lagrangian particle model, used in CFD simulations, too. 18 refs., 5 figs., 5 tabs.

Oxy-fuel combustion of coal and biomass, the effect on radiative and convective heat transfer and burnout

Energy Technology Data Exchange (ETDEWEB)

Smart, John P.; Patel, Rajeshriben; Riley, Gerry S. [RWEnpower, Windmill Hill Business Park, Whitehill Way, Swindon, Wiltshire SN5 6PB, England (United Kingdom)

2010-12-15

This paper focuses on results of co-firing coal and biomass under oxy-fuel combustion conditions on the RWEn 0.5 MWt Combustion Test Facility (CTF). Results are presented of radiative and convective heat transfer and burnout measurements. Two coals were fired: a South African coal and a Russian Coal under air and oxy-fuel firing conditions. The two coals were also co-fired with Shea Meal at a co-firing mass fraction of 20%. Shea Meal was also co-fired at a mass fraction of 40% and sawdust at 20% with the Russian Coal. An IFRF Aerodynamically Air Staged Burner (AASB) was used. The thermal input was maintained at 0.5 MWt for all conditions studied. The test matrix comprised of varying the Recycle Ratio (RR) between 65% and 75% and furnace exit O{sub 2} was maintained at 3%. Carbon-in-ash samples for burnout determination were also taken. Results show that the highest peak radiative heat flux and highest flame luminosity corresponded to the lowest recycle ratio. The effect of co-firing of biomass resulted in lower radiative heat fluxes for corresponding recycle ratios. Furthermore, the highest levels of radiative heat flux corresponded to the lowest convective heat flux. Results are compared to air firing and the air equivalent radiative and convective heat fluxes are fuel type dependent. Reasons for these differences are discussed in the main text. Burnout improves with biomass co-firing under both air and oxy-fuel firing conditions and burnout is also seen to improve under oxy-fuel firing conditions compared to air. (author)

Catalytic burners in larger boiler appliances

Energy Technology Data Exchange (ETDEWEB)

Silversand, Fredrik; Persson, Mikael (Catator AB, Lund (Sweden))

2009-02-15

This project focuses on the scale up of a Catator's catalytic burner technology to enable retrofit installation in existing boilers and the design of new innovative combinations of catalytic burners and boilers. Different design approaches are discussed and evaluated in the report and suggestions are made concerning scale-up. Preliminary test data, extracted from a large boiler installation are discussed together with an accurate analysis of technical possibilities following an optimization of the boiler design to benefit from the advantages of catalytic combustion. The experimental work was conducted in close collaboration with ICI Caldaie (ICI), located in Verona, Italy. ICI is a leading European boiler manufacturer in the effect segment ranging from about 20 kWt to several MWt. The study shows that it is possibly to scale up the burner technology and to maintain low emissions. The boilers used in the study were designed around conventional combustion and were consequently not optimized for implementation of catalytic burners. From previous experiences it stands clear that the furnace volume can be dramatically decreased when applying catalytic combustion. In flame combustion, this volume is normally dimensioned to avoid flame impingement on cold surfaces and to facilitate completion of the gas-phase reactions. The emissions of nitrogen oxides can be reduced by decreasing the residence time in the furnace. Even with the over-dimensioned furnace used in this study, we easily reached emission values close to 35 mg/kWh. The emissions of carbon monoxide and unburned hydrocarbons were negligible (less than 5 ppmv). It is possible to decrease the emissions of nitrogen oxides further by designing the furnace/boiler around the catalytic burner, as suggested in the report. Simultaneously, the size of the boiler installation can be reduced greatly, which also will result in material savings, i.e. the production cost can be reduced. It is suggested to optimize the

The effects of coal quality on NO{sub x} emissions and carbon burnout in pulverised coal-fired utility boilers

Energy Technology Data Exchange (ETDEWEB)

O`Connor, M. [National Power plc, Swindon (United Kingdom)

1999-04-01

A comprehensive study is reported on the impact of coal quality on nitrogen oxides emissions and carbon burnout in utility boilers, with the aim of assessing their relationship and developing predictive tools for assessing coals. Experimental work was carried out on various laboratory-scale apparatus and on single burner test facilities ranging from 160 kW{sub th} to 40 MW{sub th} in size and measurements were obtained from full-scale 500 MW{sub e} utility boiler trials. This data and basic coal data were then used to develop mathematical models to predict full-scale boiler performance with respect to NO{sub x} emissions and carbon burnout. Power station trials demonstrated that coal quality effects nitrogen oxides and burnout. The variability in boiler conditions also impacted on these factors. Lower nitrogen and higher volatile coals generally produced less NO{sub x}. Volatile content was the most important generic coal property for predicting burnout. Modelling rig tests, using data from advanced laboratory-scale tests, were found to be just as successful as using rig tests for predicting NO{sub x} performance of different coals. Laboratory-scale tests were found to be successful in providing accurate predictions of burnout for the coals studied. Mathematical models, however, were found to be less successful in this area and further work to develop this is required. A major achievement was CFD solutions of full-scale utility boiler furnaces in a single mesh. 32 refs., 15 figs., 33 tabs., 2 apps.

Comparative analyses for selected clean coal technologies in the international marketplace

Energy Technology Data Exchange (ETDEWEB)

Szpunar, C.B.; Gillette, J.L.

1990-07-01

Clean coal technologies (CCTs) are being demonstrated in research and development programs under public and private sponsorship. Many of these technologies could be marketed internationally. To explore the scope of these international opportunities and to match particular technologies with markets appearing to have high potential, a study was undertaken that focused on seven representative countries: Italy, Japan, Morocco, Turkey, Pakistan, the Peoples' Republic of China, and Poland. The results suggest that there are international markets for CCTs and that these technologies can be cost competitive with more conventional alternatives. The identified markets include construction of new plants and refurbishment of existing ones, especially when decision makers want to decrease dependence on imported oil. This report describes potential international market niches for U.S. CCTs and discusses the status and implications of ongoing CCT demonstration activities. Twelve technologies were selected as representative of technologies under development for use in new or refurbished industrial or electric utility applications. Included are the following: Two generic precombustion technologies: two-stage froth-flotation coal beneficiation and coal-water mixtures (CWMs); Four combustion technologies: slagging combustors, integrated-gasification combined-cycle (IGCC) systems, atmospheric fluidized-bed combustors (AFBCs), and pressurized fluidized-bed combustors (PFBCs); and Six postcombustion technologies: limestone-injection multistage burner (LIMB) systems, gas-reburning sorbent-injection (GRSI) systems, dual-alkali flue-gas desulfurization (FGD), spray-dryer FGD, the NOXSO process, and selective catalytic reduction (SCR) systems. Major chapters of this report have been processed separately for inclusion on the data base.

Performance and analysis by particle image velocimetry (PIV) of cooker-top burners in Thailand

International Nuclear Information System (INIS)

Makmool, U.; Jugjai, S.; Tia, S.; Vallikul, P.; Fungtammasan, B.

2007-01-01

Cooker-top burners are used extensively in Thailand because of the rapid combustion and high heating-rates created by an impinging flame, which is characteristic of these types of burners. High thermal efficiency with low level of CO emissions is the most important performance criteria for these burners. The wide variation in reported performances of the burners appears to be due to the ad hoc knowledge gained through trial and error of the local manufacturers rather than sound scientific principles. This is extremely undesirable in view of safety, energy conservation and environmental protection. In the present work, a nationwide cooker-top burner performance survey and an implementation of a PIV technique to analyze the burner performance as well as advising local manufacturers were carried out. Experimental data were reported for the base line value of thermal efficiency of all the burners. The thermal performance parameters and dynamic properties of the flow field at a flame impingement area, i.e. velocity magnitude, turbulent intensity, vorticity and strain rate were also reported as a function of burner type, which was categorized into four types based on the configuration of the burner head: radial flow burners, swirling flow burners, vertical flow burners and porous radiant burners

Research program for an environmentally-friendly coal utilization system in the Philippines

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

Feasibility studies are conducted on the introduction of an environmentally-friendly coal utilization system into the Filipino electric power industry, cement industry, and domestic fuel sector. The studies cover the current status of economy and energy in that country, supply and demand of coal, environmental protection and Government's policy, study of the above-said system relative to its application to the fields of electric power industry, cement industry, and domestic fuel sector, and a study about the effective utilization of Filipino domestic coal by the use of the system. Imported coal is used in the electric power industry because of its cost and quality. It is learned after research, however, that domestic coal will be able to compete against imported coal when some technologies are resorted to, such as those pertinent to denitrification in the furnace, novel low-NOx burner, coal pulverization, and combustion diagnosis. As for the treatment of flue gas, it is concluded that the simplified wet lime/gypsum process will be suitable. It is inferred that the CWM (coal-water mixture) process technology will be effective for the utilization of domestic low-grade coal. (NEDO)

Research program for an environmentally-friendly coal utilization system in the Philippines

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

Feasibility studies are conducted on the introduction of an environmentally-friendly coal utilization system into the Filipino electric power industry, cement industry, and domestic fuel sector. The studies cover the current status of economy and energy in that country, supply and demand of coal, environmental protection and Government's policy, study of the above-said system relative to its application to the fields of electric power industry, cement industry, and domestic fuel sector, and a study about the effective utilization of Filipino domestic coal by the use of the system. Imported coal is used in the electric power industry because of its cost and quality. It is learned after research, however, that domestic coal will be able to compete against imported coal when some technologies are resorted to, such as those pertinent to denitrification in the furnace, novel low-NOx burner, coal pulverization, and combustion diagnosis. As for the treatment of flue gas, it is concluded that the simplified wet lime/gypsum process will be suitable. It is inferred that the CWM (coal-water mixture) process technology will be effective for the utilization of domestic low-grade coal. (NEDO)

Assessment of PWR plutonium burners for nuclear energy centers

International Nuclear Information System (INIS)

Frankel, A.J.; Shapiro, N.L.

1976-06-01

The purpose of the study was to explore the performance and safety characteristics of PWR plutonium burners, to identify modifications to current PWR designs to enhance plutonium utilization, to study the problems of deploying plutonium burners at Nuclear Energy Centers, and to assess current industrial capability of the design and licensing of such reactors. A plutonium burner is defined to be a reactor which utilizes plutonium as the sole fissile addition to the natural or depleted uranium which comprises the greater part of the fuel mass. The results of the study and the design analyses performed during the development of C-E's System 80 plant indicate that the use of suitably designed plutonium burners at Nuclear Energy Centers is technically feasible

Emission spectroscopy for coal-fired cyclone furnace diagnostics

Energy Technology Data Exchange (ETDEWEB)

Wehrmeyer, J.A.; Boll, D.E.; Smith, R. [Vanderbilt University, Nashville, TN (United States). Dept. of Mechanical Engineering

2003-08-01

Using a spectrograph and charge-coupled device (CCD) camera, ultraviolet and visible light emission spectra were obtained from a coal-burning electric utility's cyclone furnaces operating at either fuel-rich or fuel-lean conditions. The aim of this effort is to identify light emission signals that can be related to a cyclone furnace's operating condition in order to adjust its air/fuel ratio to minimize pollutant production. Emission spectra at the burner and outlet ends of cyclone furnaces were obtained. Spectra from all cyclone burners show emission lines for the trace elements Li, Na, K, and Rb, as well as the molecular species OH and CaOH. The Ca emission line is detected at the burner end of both the fuel-rich and fuellean cyclone furnaces but is not detected at the outlet ends of either furnace type. Along with the disappearance of Ca is a concomitant increase in the CaOH signal at the outlet end of both types of furnaces. The OH signal strength is in general stronger when viewing at the burner end rather than the exhaust end of both the fuel-rich and fuel-lean cyclone furnaces, probably due to high, non-equilibrium amounts of OH present inside the furnace. Only one molecular species was detected that could be used as a measure of air/fuel ratio: MgOH. It was detected at the burner end of fuel-rich cyclone furnaces but not detected in fuel-lean cyclone furnaces. More direct markers of air/fuel ratio, such as CO and 02 emission, were not detected, probably due to the generally weak nature of molecular emission relative to ambient blackbody emission present in the cyclone furnaces, even at ultraviolet wavelengths.

Evaluation of a high-temperature burner-duct-recuperator system

Science.gov (United States)

1990-07-01

The U.S. Department of Energy's (DOE) Office of Industrial Technologies (OIT) sponsors research and development (R and D) to improve the energy efficiency of American industry and to provide for fuel flexibility. OIT has funded a multiyear R and D project by the Babcock and Wilcox Company (B and W) to design, fabricate, field test, and evaluate a high-temperature burner-duct-recuperator (HTBDR) system. This ceramic-based recuperator system recovers waste heat from the corrosive, high-temperature (2170 F) flue gas stream of a steel soaking pit to preheat combustion air to as high as 1700 F. The preheated air is supplied to a high-temperature burner. The B and W R and D program, which is now complete, involved several activities, including selecting and evaluating ceramic materials, designing the system, and developing and evaluating the prototype. In addition, a full-scale unit was tested at a B and W steel soaking pit. The full-scale system consisted of a modular single-stage ceramic recuperator, a conventional two-pass metallic recuperator, a high-temperature burner, fans, insulated ducting, and associated controls and instrumentation. The metallic recuperator preheated combustion air to about 750 F before it passed to the ceramic module. This technical case study describes the DOE/B and W recuperator project and highlights the field tests of the full-scale recuperator system. The document makes results of field tests and data analysis available to other researchers and private industry. It discusses project status, summarizes field tests, and reviews the potential effects the technology will have on energy use and system economics.

Coal 95; Kol - 95

Energy Technology Data Exchange (ETDEWEB)

Sparre, C

1996-12-31

The report deals with the use of coal and coke in Sweden during 1994. Some information about technology, environmental questions and markets are also given. Data have been collected by questionnaires to major users and by telephone to minor users. Preliminary statistical data from Statistics Sweden have also been used.The use of steam coal for heating purposes has been unchanged during 1994 at a level of 1 Mtons. The production in the cogeneration plants has been constant, but has increased for electricity production. The minor plants have increased their use of forest fuels. The use of steam coal will probably go down in the next years both for heat and cogeneration plants. During the top year 1987 coal was used in 18 hot water and 11 cogeneration plants. 1994 these figures are 3 and 12. Taxes and environmental reasons explain this trend. The use of steam coal in industry has been constant at the level 0.7 Mtons. The import of metallurgical coal in 1993 was 1.6 Mtons, like 1992. Import of 0.3 Mtons of coke gives the total consumption of coke in industry as 1.5 Mtons. the average price of steam coal imported to Sweden was 317 SEK/ton, 3% higher than 1993. All Swedish plants meet their emission limit of dust, SO{sub 2} and NO{sub x} as given by county administrations or concession boards. The cogeneration plants all have some SO{sub 2} removal system. The biggest cogeneration plant (Vaesteraas) has recently invested in a SCR NO{sub x} cleaning system. Most other plants use low NO{sub x} burners or SNR injection systems based on ammonia or urea. 2 figs, 13 tabs.

Characterization of Oxy-combustion Impacts in Existing Coal-fired Boilers

Energy Technology Data Exchange (ETDEWEB)

Adams, Bradley [Univ. of Utah, Salt Lake City, UT (United States); Davis, Kevin [Univ. of Utah, Salt Lake City, UT (United States); Senior, Constance [Univ. of Utah, Salt Lake City, UT (United States); Shim, Hong Shim [Univ. of Utah, Salt Lake City, UT (United States); Otten, Brydger Van [Univ. of Utah, Salt Lake City, UT (United States); Fry, Andrew [Univ. of Utah, Salt Lake City, UT (United States); Wendt, Jost [Univ. of Utah, Salt Lake City, UT (United States); Eddings, Eric [Univ. of Utah, Salt Lake City, UT (United States); Paschedag, Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Shaddix, Christopher [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cox, William [Brigham Young Univ., Provo, UT (United States); Tree, Dale [Brigham Young Univ., Provo, UT (United States)

2013-09-30

Reaction Engineering International (REI) managed a team of experts from University of Utah, Siemens Energy, Praxair, Vattenfall AB, Sandia National Laboratories, Brigham Young University (BYU) and Corrosion Management Ltd. to perform multi-scale experiments, coupled with mechanism development, process modeling and CFD modeling, for both applied and fundamental investigations. The primary objective of this program was to acquire data and develop tools to characterize and predict impacts of CO{sub 2} flue gas recycle and burner feed design on flame characteristics (burnout, NO{sub x}, SO{sub x}, mercury and fine particle emissions, heat transfer) and operational concerns (fouling, slagging and corrosion) inherent in the retrofit of existing coal-fired boilers for oxy-coal combustion. Experimental work was conducted at Sandia National Laboratories’ Entrained Flow Reactor, the University of Utah Industrial Combustion Research Facility, and Brigham Young University. Process modeling and computational fluid dynamics (CFD) modeling was performed at REI. Successful completion of the project objectives resulted in the following key deliverables: 1) Multi-scale test data from 0.1 kW bench-scale, 100 kW and 200 kW laboratory-scale, and 1 MW semi-industrial scale combustors that describe differences in flame characteristics, fouling, slagging and corrosion for coal combustion under air-firing and oxygen-firing conditions, including sensitivity to oxy-burner design and flue gas recycle composition. 2) Validated mechanisms developed from test data that describe fouling, slagging, waterwall corrosion, heat transfer, char burnout and sooting under coal oxy-combustion conditions. The mechanisms were presented in a form suitable for inclusion in CFD models or process models. 3) Principles to guide design of pilot-scale and full-scale coal oxy-firing systems and flue gas recycle configurations, such that boiler operational impacts from oxy-combustion retrofits are minimized. 4

Characterization of Oxy-combustion Impacts in Existing Coal-fired Boilers

Energy Technology Data Exchange (ETDEWEB)

Bradley Adams; Andrew Fry; Constance Senior; Hong Shim; Huafeng Wang; Jost Wendt; Christopher Shaddix

2009-06-30

This report summarizes Year 1 results of a research program designed to use multi-scale experimental studies and fundamental theoretical models to characterize and predict the impacts of retrofit of existing coal-fired utility boilers for oxy-combustion. Through the course of Year 1 activities, great progress was made toward understanding the issues associated with oxy-combustion retrofit of coal-fired boilers. All four Year 1 milestones and objectives have been, or will be, completed on schedule and within budget. Progress in the four milestone areas may be summarized as follows: • University of Utah has performed size segregated ash composition measurements in the Oxy-Fuel Combustor (OFC). These experiments indicate that oxy-combustion retrofit may impact ash aerosol mineral matter composition. Both flame temperature and flue gas composition have been observed to influence the concentration of calcium, magnesium and iron in the fine particulate. This could in turn impact boiler fouling and slagging. • Sandia National Labs has shown that char oxidation rate is dependent on particle size (for sizes between 60 and 100 microns) by performing fundamental simulations of reacting char particles. These predictions will be verified by making time-resolved optical measurements of char particle temperature, velocity and size in bench-scale experiments before the end of Year 1. • REI and Siemens have completed the design of an oxy-research burner that will be mounted on University of Utah’s pilot-scale furnace, the L1500. This burner will accommodate a wide range of O2, FGR and mixing strategies under conditions relevant for utility boiler operation. Through CFD modeling of the different burner designs, it was determined that the key factor influencing flame stabilization location is particle heat-up rate. The new oxy-research burner and associated equipment is scheduled for delivery before the end of Year 1. • REI has completed a literature survey of slagging and

Effects of elliptical burner geometry on partially premixed gas jet flames in quiescent surroundings

Science.gov (United States)

Baird, Benjamin

This study is the investigation of the effect of elliptical nozzle burner geometry and partial premixing, both 'passive control' methods, on a hydrogen/hydrocarbon flame. Both laminar and turbulent flames for circular, 3:1, and 4:1 aspect ratio (AR) elliptical burners are considered. The amount of air mixed with the fuel is varied from fuel-lean premixed flames to fuel-rich partially premixed flames. The work includes measurements of flame stability, global pollutant emissions, flame radiation, and flame structure for the differing burner types and fuel conditions. Special emphasis is placed on the near-burner region. Experimentally, both conventional (IR absorption, chemiluminecent, and polarographic emission analysis,) and advanced (laser induced fluorescence, planar laser induced fluorescence, Laser Doppler Velocimetry (LDV), Rayleigh scattering) diagnostic techniques are used. Numerically, simulations of 3-dimensional laminar and turbulent reacting flow are conducted. These simulations are run with reduced chemical kinetics and with a Reynolds Stress Model (RSM) for the turbulence modeling. It was found that the laminar flames were similar in appearance and overall flame length for the 3:1 AR elliptical and the circular burner. The laminar 4:1 AR elliptical burner flame split into two sub-flames along the burner major axis. This splitting had the effect of greatly shortening the 4:1 AR elliptical burner flame to have an overall flame length about half of that of the circular and 3:1 AR elliptical burner flames. The length of all three burners flames increased with increasing burner exit equivalence ratio. The blowout velocity for the three burners increased with increase in hydrogen mass fraction of the hydrogen/propane fuel mixture. For the rich premixed flames, the circular burner was the most stable, the 3:1 AR elliptical burner, was the least stable, and the 4:1 AR elliptical burner was intermediate to the two other burners. This order of stability was due

Influence of Process Parameters on Coal Combustion Performance

DEFF Research Database (Denmark)

Lans, Robert Pieter Van Der

investigated experimentally in a 400 MWe corner fired boiler with over fire air, a 350 MWe opposed fired boiler, and in a 160 kWt pilot scale test rig. Three different coals were fired in each of the furnaces as part of the activities in group 3 of the European Union JOULE 2 Extension project "Atmospheric......The objective of this study is to improve the understanding of nitrogen oxide formation and carbon burnout during the combustion of pulverized coal, and to contribute to addressing the potential of chemical engineering models for the prediction of furnace temperatures, NO emissions and the amount...... of carbon in ash. To this purpose, the effect of coal quality on NO and burnout has been investigated experimentally, a radiation heat balance has been developed based on simple chemical engineering methodology, and a mixing study has been conducted in order to describe the near burner macro mixing in terms...

Sensitivity of Transmutation Capability to Recycling Scenarios in KALIMER-600 TRU Burner

International Nuclear Information System (INIS)

Lee, Yong Kyo; Kim, Myung Hyun

2013-01-01

The purpose of this study is to test transmutation and design feasibility of KALIMER burner caused from many limitations in recycling options; such as low recovery factors and external feed. Design impact from many recycling options will be tested as a sensitivity to various recycling process parameters under many recycling scenarios. Through this study, possibilities when Pyro-processing is realized with SFR can be expected in the recycling scenarios. For the development of sodium-cooled fast reactor(SFR) technology, prototype KALIMER plant is now under R and D stage in Korea. For the future application of SFR for waste transmutation, KALIMER core was designed for TRU burner by KAERI. Feasibility of TRU burner cannot be evaluated exactly because overall functional parameters in pyro-processing recycling process has not been verified yet. There is great possibility to accept undesirable process functions in pyro-processing. Only TRU nuclides composition a little differs between PWR SF and CANDU SF so first scenario has no problem operating SFR. In second scenario, the radiotoxicity of waste at 99% of TRU RF have to be confirmed whether it is proper level to reposit as Low and Intermediate Level Wastes or not. And the reactor safety at high RF of RE must be inspected. Not only third scenario but also several scenarios for good measure are being calculated and will be evaluated

Fiscal 1994 survey report. Coal hydrogasification technology development; 1994 nendo sekitan suiten gaska gijutsu kaihatsu chosa hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-03-01

Surveys and studies were conducted to establish a practical SNG (substitute natural gas) production process. For the development of an ARCH (advanced rapid coal hydrogasification) process, a plan was prepared covering the basic concept of the process, overall development program, hydrogen/oxygen burner, and an injector. The overall development program comprises element studies (4 years) and the study of the operation of a 50 tons/day pilot plant (8 years), and deals with the development of a reactor and peripheral equipment. Next comes a total system verification effort using a 200 tons/day verification plant in combination with a hydrogen production process, and this aims to achieve commercialization at 3 million Nm{sup 3}/day. As for the hydrogen/oxygen burner, a structure was proposed after surveys of literature and patents on burner structures, ignition methods, and monitoring methods. In the development of an injector, a plan was prepared for testing, and improving, the performance in a cold/hot model of a specimen incorporating the proposed hydrogen/oxygen burner. Basic studies to be carried out include simulation-aided performance prediction. (NEDO)

Central recirculation zone analysis in an unconfined tangential swirl burner with varying degrees of premixing

Energy Technology Data Exchange (ETDEWEB)

Valera-Medina, A. [CIATEQ, Parque Industrial Bernardo Quintana, Turbomachinery Department, Queretaro (Mexico); Syred, N.; Kay, P.; Griffiths, A. [Cardiff University, School of Engineering, Cardiff, Wales (United Kingdom)

2011-06-15

Swirl-stabilised combustion is one of the most widely used techniques for flame stabilisation, uses ranging from gas turbine combustors to pulverised coal-fired power stations. In gas turbines, lean premixed systems are of especial importance, giving the ability to produce low NOx systems coupled with wide stability limits. The common element is the swirl burner, which depends on the generation of an aerodynamically formed central recirculation zone (CRZ) and which serves to recycle heat and active chemical species to the root of the flame as well as providing low-velocity regions where the flame speed can match the local flow velocity. Enhanced mixing in and around the CRZ is another beneficial feature. The structure of the CRZ and hence that of the associated flames, stabilisation and mixing processes have shown to be extremely complex, three-dimensional and time dependent. The characteristics of the CRZ depend very strongly on the level of swirl (swirl number), burner configuration, type of flow expansion, Reynolds number (i.e. flowrate) and equivalence ratio. Although numerical methods have had some success when compared to experimental results, the models still have difficulties at medium to high swirl levels, with complex geometries and varied equivalence ratios. This study thus focuses on experimental results obtained to characterise the CRZ formed under varied combustion conditions with different geometries and some variation of swirl number in a generic swirl burner. CRZ behaviour has similarities to the equivalent isothermal state, but is strongly dependent on equivalence ratio, with interesting effects occurring with a high-velocity fuel injector. Partial premixing and combustion cause more substantive changes to the CRZ than pure diffusive combustion. (orig.)

Methane combustion in catalytic premixed burners

International Nuclear Information System (INIS)

Cerri, I.; Saracco, G.; Specchia, V.

1999-01-01

Catalytic premixed burners for domestic boiler applications were developed with the aim of achieving a power modularity from 10 to 100% and pollutant emissions limited to NO x 2 , where the combustion took place entirely inside the burner heating it to incandescence and allowing a decrease in the flame temperature and NO x emissions. Such results were confirmed through further tests carried out in a commercial industrial-scale boiler equipped with the conical panels. All the results, by varying the excess air and the heat power employed, are presented and discussed [it

Design evaluation of the 20-cm (8-inch) secondary burner system

International Nuclear Information System (INIS)

Rode, J.S.

1977-08-01

This report describes an evaluation of the design of the existing 20-cm (8-inch) engineering-scale secondary burner system in the HTGR reprocessing cold pilot plant at General Atomic Co. The purpose of this evaluation is to assess the suitability of the existing design as a prototype of the HTGR Recycle Demonstration Facility (HRDF) secondary burner system and to recommend alternatives where the existing design is thought to be unsuitable as a prototype. This evaluation has led to recommendations for the parallel development of two integrated design concepts for a prototype secondary burner system. One concept utilizes the existing burner heating and cooling subsystems in order to minimize development risk, but simplifies a number of other features associated with remote maintenance and burner operation. The other concept, which offers maximum cost reduction, utilizes internal gas cooling of the burner, retains the existing heating subsystem for design compatibility, but requires considerable development to reduce the risk to acceptable limits. These concepts, as well as other design alternatives, are described and evaluated

Design evaluation of the 40-cm (16-inch) primary burner system

International Nuclear Information System (INIS)

Rode, J.S.

1977-06-01

An evaluation is given of the design of the existing 40-cm (16-in.) engineering-scale primary burner system in the HTGR reprocessing cold pilot plant at General Atomic Co. The purpose of this evaluation is to assess the suitability of the existing design as a prototype of the HTGR Recycle Demonstration Facility (HRDF) primary burner system and to recommend alternatives where the existing design is thought to be unsuitable as a prototype. This evaluation has led to recommendations for the parallel development of two integrated design concepts for a prototype primary burner system. One concept utilizes the existing burner heating and cooling sub-systems in order to minimize development risk, but simplifies a number of other features associated with remote maintenance and burner operation. The other concept, which offers maximum cost reduction, utilizes direct contact hot gas heating and internal gas cooling of the burner, but requires considerable development to reduce the risk to acceptable limits. These concepts, as well as other design alternatives, are described and evaluated

New stage of clean coal technology in Japan; Clean coal technology no aratana tenkai ni tsuite

Energy Technology Data Exchange (ETDEWEB)

Kawaguchi, Y [Agency of Natural Resources and Energy, Tokyo (Japan)

1996-09-01

The paper described the positioning and new development of clean coal technology. Coal is an important resource which supplies approximately 30% of the energy consumed in all the world. In the Asian/Pacific region, especially, a share of coal in energy is high, around 60% of the world, and it is indispensable to continue using coal which is abundantly reserved. Japan continues using coal as an important energy among petroleum substituting energies taking consideration of the global environment, and is making efforts for development and promotion of clean coal technology aiming at further reduction of environmental loads. Moreover, in the Asian region where petroleum depends greatly upon outside the region, it is extremely important for stabilization of Japan`s energy supply that coal producing countries in the region promote development/utilization of their coal resources. For this, it is a requirement for Japan to further a coal policy having an outlook of securing stable coal supply/demand in the Asian region. 6 figs., 2 tabs.

Desulfurization and denitrogenation of coal during multi-stage hydropyrolysis

Energy Technology Data Exchange (ETDEWEB)

Wang, N.; Li, W.; Li, B. [Chinese Academy of Sciences, Taiyuan (China). State Key Lab of Coal Conversion

2001-02-01

The elemental composition of char of high sulfur Hongmiao coal in multi-stage hydropyrolysis (MHyPy) with different heating rates were analysed and compared with that from normal hydropyrolysis (HyPy). The results illustrated that the sulfur removal in MHyPy was greater than that in HyPy, and more sulfur was evolved as the easily recycled gas H{sub 2}S. Similar with the situation of sulfur, more nitrogen transferred to the gas phase easily to be dealt with and the clean char was obtained. During MHyPy the extent of desulfurization and denitrogenation was more remarkable at high rate than that at slow heating rate. 8 refs., 2 figs., 2 tabs.

Environmental issues affecting clean coal technology deployment

Energy Technology Data Exchange (ETDEWEB)

Miller, M.J. [Electric Power Research Inst., Palo Alto, CA (United States)

1997-12-31

The author outlines what he considers to be the key environmental issues affecting Clean Coal Technology (CCT) deployment both in the US and internationally. Since the international issues are difficult to characterize given different environmental drivers in various countries and regions, the primary focus of his remarks is on US deployment. However, he makes some general remarks, particularly regarding the environmental issues in developing vs. developed countries and how these issues may affect CCT deployment. Further, how environment affects deployment depends on which particular type of clean coal technology one is addressing. It is not the author`s intention to mention many specific technologies other than to use them for the purposes of example. He generally categorizes CCTs into four groups since environment is likely to affect deployment for each category somewhat differently. These four categories are: Precombustion technologies such as coal cleaning; Combustion technologies such as low NOx burners; Postcombustion technologies such as FGD systems and postcombustion NOx control; and New generation technologies such as gasification and fluidized bed combustion.

Some parameters and conditions defining the efficiency of burners ...

Indian Academy of Sciences (India)

irradiation in special burners, namely, in the blankets of ADS. Various views ... Ecologic gain – ratio of the ecologic threat level of initial LLW to that of final. LLW. .... For all burner types, the general tendency is that the increase of consumption.

Characterization of combustion in a fabric singeing burner operating with varsol

International Nuclear Information System (INIS)

Quintana M, Juan C; Mendoza S, Cesar Camilo; Molina Alejandro

2009-01-01

The textile industry uses singeing burners to diminish the amount of pilling on surface fabrics. Some of these burners use Stoddard solvent which has high cost per unit of energy, high flammability and emits volatile organic compounds that pose an occupational safety hazard. This study characterized a singing burner operating with varsol performing measurements of temperature downstream the burner, air and fuel flows, and concentration of CO, CO 2 , O 2 and NO x . These measurements defined the most important characteristics of the Stoddard solvent flame that should be maintained to obtain a similar behavior in an eventual change to natural gas.

Numerical study on NO formation in a pulverized coal-fired furnace using oxy-fuel combustion

Energy Technology Data Exchange (ETDEWEB)

Zhang, Aiyue; Chen, Yuan; Sheng, Changdong [Southeast Univ., Nanjing (China). School of Energy and Environment

2013-07-01

Computational fluid dynamics (CFD) approach was employed to numerically investigate NO formation in a 600 MW wall-fired pulverized coal-fired furnace retrofitted for oxy-coal combustion, aimed at the impacts of flue gas recycle ratio, O{sub 2} staging and recycled NO with the recycled flue gas (RFG) on NO formation and emission. An in-house CFD research code for conventional air combustion was developed and extended to simulate O{sub 2}/RFG combustion with specific considerations of the change of gas properties and its impact on coal particle combustion processes. The extended De Soete mechanisms including NO reburning mechanism were applied to describe transformations of fuel nitrogen. It was shown that CFD simulation represented the significant reduction of NO formation during O{sub 2}/RFG combustion compared to that during air combustion. The in-burner and particularly the in-furnace O{sub 2} staging were confirmed still to play very important roles in NO formation control. Changing the recycle ratio had significant impact on the combustion performance and consequently on NO formation and emission. With the combustion performance ensured, decreasing the flue gas recycle ratio or increasing the inlet O{sub 2} concentration of combustion gas led to reduction of NO formation and emission. Although NO formation and emission was found to increase with increasing the inlet NO concentration of combustion gas, CFD simulation indicated that {proportional_to}74% of the inlet NO was reduced in the furnace, consistent with the experimental data reported in the literature. This demonstrated the significant contribution of reburning mechanism to the reduction of the recycled NO in the furnace.

Parametric Study of High-Efficiency and Low-Emission Gas Burners

Directory of Open Access Journals (Sweden)

Shuhn-Shyurng Hou

2013-01-01

Full Text Available The objective of this study is to investigate the influence of three significant parameters, namely, swirl flow, loading height, and semi-confined combustion flame, on thermal efficiency and CO emissions of a swirl flow gas burner. We focus particularly on the effects of swirl angle and inclination angle on the performance of the swirl flow burner. The results showed that the swirl flow burner yields higher thermal efficiency and emits lower CO concentration than those of the conventional radial flow burner. A greater swirl angle results in higher thermal efficiency and CO emission. With increasing loading height, the thermal efficiency increases but the CO emission decreases. For a lower loading height (2 or 3 cm, the highest efficiency occurs at the inclination angle 15°. On the other hand, at a higher loading height, 4 cm, thermal efficiency increases with the inclination angle. Moreover, the addition of a shield can achieve a great increase in thermal efficiency, about 4-5%, and a decrease in CO emissions for the same burner (swirl flow or radial flow.

Effect of the Reburning Zone Stoichiometry on the Nox Concentration at the Three-Stage Combustion of Pulverized Coal

Directory of Open Access Journals (Sweden)

Chernetskaya Nelya

2016-01-01

Full Text Available Numerical study of heat and mass transfer taking into account the combustion of coal particles in the furnace at the three-stage combustion of pulverized coal was performed. Analysis of the reburning zone stoichiometry on the concentration of nitrogen oxides at the furnace outlet was made. The values of excess air in the primary and reburning combustion zones, providing for the concentration of nitrogen oxides at the furnace outlet is not more than 350 mg/m3 and unburned carbon not more than 1 % when burning coal with a high content of nitrogen were established.

Oxy-Combustion Burner and Integrated Pollutant Removal Research and Development Test Facility

Energy Technology Data Exchange (ETDEWEB)

Mark Schoenfield; Manny Menendez; Thomas Ochs; Rigel Woodside; Danylo Oryshchyn

2012-09-30

A high flame temperature oxy-combustion test facility consisting of a 5 MWe equivalent test boiler facility and 20 KWe equivalent IPR® was constructed at the Hammond, Indiana manufacturing site. The test facility was operated natural gas and coal fuels and parametric studies were performed to determine the optimal performance conditions and generated the necessary technical data required to demonstrate the technologies are viable for technical and economic scale-up. Flame temperatures between 4930-6120F were achieved with high flame temperature oxy-natural gas combustion depending on whether additional recirculated flue gases are added to balance the heat transfer. For high flame temperature oxy-coal combustion, flame temperatures in excess of 4500F were achieved and demonstrated to be consistent with computational fluid dynamic modeling of the burner system. The project demonstrated feasibility and effectiveness of the Jupiter Oxygen high flame temperature oxy-combustion process with Integrated Pollutant Removal process for CCS and CCUS. With these technologies total parasitic power requirements for both oxygen production and carbon capture currently are in the range of 20% of the gross power output. The Jupiter Oxygen high flame temperature oxy-combustion process has been demonstrated at a Technology Readiness Level of 6 and is ready for commencement of a demonstration project.

MINIMIZATION OF CARBON LOSS IN COAL REBURNING

International Nuclear Information System (INIS)

Lissianski, Vitali V.; Loc Ho; Maly, Peter M.; Zamansky, Vladimir M.

2002-01-01

This project develops Fuel-Flexible Reburning (FFR), which combines conventional reburning and Advanced Reburning (AR) technologies with an innovative method of delivering coal as the reburning fuel. The FFR can be retrofit to existing boilers and can be configured in several ways depending on the boiler, coal characteristics, and NO x control requirements. Fly ash generated by the technology will be a saleable byproduct for use in the cement and construction industries. FFR can also reduce NO x by 60%-70%, achieving an emissions level of 0.15 lb/10 6 Btu in many coal-fired boilers equipped with Low NO x Burners. Total process cost is expected to be one third to one half of that for Selective Catalytic Reduction (SCR). Activities during reporting period included design, manufacture, assembly, and shake down of the coal gasifier and pilot-scale testing of the efficiency of coal gasification products in FFR. Tests were performed in a 300 kW Boiler Simulator Facility. Several coals with different volatiles content were tested. Data suggested that incremental increase in the efficiency of NO x reduction due to the gasification was more significant for less reactive coals with low volatiles content. Experimental results also suggested that the efficiency of NO x reduction in FFR was higher when air was used as a transport media. Up to 14% increase in the efficiency of NO x reduction in comparison with that of basic reburning was achieved with air transport. Temperature and residence time in the gasification zone also affected the efficiency of NO x reduction

Southeast Asia - air pollution control and coal-fired power generation

Energy Technology Data Exchange (ETDEWEB)

Soud, H.N.

1997-12-01

Coal-fired power generation in Southeast Asia continues to grow in order to satisfy the increasing demand for electricity throughout the region. Emissions standards have been adopted in some Southeast Asian countries. Particulate matter, SO{sub 2} and NO{sub x} emissions are the main air pollutants for which standards have been introduced. Coal cleaning, and upgrading are not used much currently. Blending is used in Thailand and is being investigated in Indonesia. Pulverised coal combustion continues to dominate the coal-fired generating capacity. FBC is used at smaller scale and in a few cases. PFBC and IGCC are considered only as options for the future. Control priority is given to particulate matter and ESPs are installed on most (existing and new) coal-fired plants. Although FGD has been installed at Mae Moh in Thailand and is planned for Paiton in Indonesia and Sual in the Philippines, the technology is still considered expensive and its application is likely to remain limited. Boiler optimisation is the main NO{sub x} abatement method currently used. It is expected that low NO{sub x} burners will be used in the future especially in new plant. 166 refs., 1 fig., 40 tabs.

Design and analysis of the federal aviation administration next generation fire test burner

Science.gov (United States)

Ochs, Robert Ian

The United States Federal Aviation Administration makes use of threat-based fire test methods for the certification of aircraft cabin materials to enhance the level of safety in the event of an in-flight or post-crash fire on a transport airplane. The global nature of the aviation industry results in these test methods being performed at hundreds of laboratories around the world; in some cases testing identical materials at multiple labs but yielding different results. Maintenance of this standard for an elevated level of safety requires that the test methods be as well defined as possible, necessitating a comprehensive understanding of critical test method parameters. The tests have evolved from simple Bunsen burner material tests to larger, more complicated apparatuses, requiring greater understanding of the device for proper application. The FAA specifies a modified home heating oil burner to simulate the effects of large, intense fires for testing of aircraft seat cushions, cargo compartment liners, power plant components, and thermal acoustic insulation. Recently, the FAA has developed a Next Generation (NexGen) Fire Test burner to replace the original oil burner that has become commercially unavailable. The NexGen burner design is based on the original oil burner but with more precise control of the air and fuel flow rates with the addition of a sonic nozzle and a pressurized fuel system. Knowledge of the fundamental flow properties created by various burner configurations is desired to develop an updated and standardized burner configuration for use around the world for aircraft materials fire testing and airplane certification. To that end, the NexGen fire test burner was analyzed with Particle Image Velocimetry (PIV) to resolve the non-reacting exit flow field and determine the influence of the configuration of burner components. The correlation between the measured flow fields and the standard burner performance metrics of flame temperature and

Studies on the catalysts for coal liquefaction. ; Kinetic discussion in initial stage of coal liquefaction. Sekitan ekikayo shokubai ni kansuru kenkyu. ; Sekitan ekika shoki dankai no sokudoronteki kosatsu

Energy Technology Data Exchange (ETDEWEB)

Muraoka, T; Ikenaga, N; Oda, H; Yokokawa, C [Kansai University, Osaka (Japan). Faculty of Engineering

1990-11-29

Discussions were given on features of various kinds of coal liquefaction catalysts exhibited by them in hydrocracking of coal (Taiheiyo coal), and particularly on selectivity of the reaction in its initial stage. Four kinds of catalysts were tested: Adkins catalyst which is an oxide of copper and chromium, Fe2O3+S, Mo-TiO2 and MoS3-Al2O3. Three grams of coal and 0.3 gram each of the catalysts were charged into an autoclave reactor and experiment was conducted under an initial hydrogen pressure of 10 MPa, temperatures from 653 K to 693 K and for durations of 0 to 120 minutes to derive apparent reaction rate constants. The MoS3-Al2O3 catalyst has promoting the reaction apparently in the primary reaction at any temperature, while the other catalysts had the rate constants varied in the initial and the later stages. It was recognized that the temperature dependence of rate constants varies considerably according to the types of catalyst. Particularly the MoO3-TiO3 catalyst has small temperature dependence in the rate constants, and high molecular weight reducing power. 3 refs., 4 figs., 3 tabs.

Development of the Radiation Stabilized Distributed Flux Burner - Phase III Final Report

Energy Technology Data Exchange (ETDEWEB)

J. D. Sullivan; A. Webb

1999-12-01

The development and demonstration of the Radiation Stabilized Burner (RSB) was completed as a project funded by the US Department of Energy Office of Industrial Technologies. The technical goals of the project were to demonstrate burner performance that would meet or exceed emissions targets of 9 ppm NOx, 50 ppm CO, and 9 ppm unburned hydrocarbons (UHC), with all values being corrected to 3 percent stack oxygen, and incorporate the burner design into a new industrial boiler configuration that would achieve ultra-low emissions while maintaining or improving thermal efficiency, operating costs, and maintenance costs relative to current generation 30 ppm low NOx burner installations. Both the ultra-low NOx RSB and the RSB boiler-burner package are now commercially available.

Modelling of NO formation in the combustion of coal blends

Energy Technology Data Exchange (ETDEWEB)

Arenillas, A.; Backreedy, R.I.; Jones, J.M.; Pis, J.J.; Pourkashanian, M.; Rubiera, F.; Williams, A. [CSIC, Instituto Nacional del Carbon, Oviedo (Spain)

2002-03-01

Coal blending is becoming of increasing importance in power stations firing pulverised coal as a result of increasing competition, stricter emission legislation and is an attractive way of improving plant economic and combustion performance. Presently, the two general methods used by power station operators to assess or predict the performance of an unknown coal blend to be fired in power station boilers are by the use of experimental large scale rig tests or correlation indices derived from experience of firing other coal blends in the power station environment. The first is expensive and the second is of doubtful accuracy in some cases. This paper evaluates the application of mathematical modelling of the combustion of a series of binary coal blends in the test situation of a drop tube reactor to predict the NO emissions and degree of char burnout. Its applicability to low NOx burners used in power stations is discussed and it is concluded that present mathematical coal combustion models are not developed sufficiently to enable an adequate description of the binary blends and the physical and chemical processes, which may include interactions, during combustion of the blend. This means that accurate predictions cannot be made. 20 refs., 4 figs., 5 tabs.

Radiative heat transfer in coal-fired furnaces and oxycoal retrofit considerations

Energy Technology Data Exchange (ETDEWEB)

Erfurth, Jens

2012-07-01

Oxycoal combustion is the combustion of coal using a mixture of oxygen and cooled recycled flue gas in place of air. In the last years it has gained interest as a means of CO{sub 2} capture from stationary point sources. In particular, under emission mitigation regimes the retrofit of existing coal-fired power plants may help avoid ''stranded assets'' through lower emissions and thus costs if certain technical criteria can be met. Among these is the need to keep total heat transfer in the boiler constant while not raising the furnace exit temperature. The altered gas composition in oxycoal combustion leads to changes in both convective and radiative heat transfer, of which the latter, while of overwhelming importance in the furnace, poses a particular challenge to modellers. This work is thus primarily concerned with the simulation of radiative heat transfer. After a short introduction to oxycoal combustion, a general discussion of Computational Fluid Dynamics (CFD) models for coal combustion is given. Emphasis is placed on the physics of molecular gas band radiation, respective modelling approaches and their application within a CFD context. Based on this analysis, it is concluded that for the purposes of this work, a non-grey CFD implementation of the Exponential Wide Band Model is most suitable. Then the results of CFD simulations of the furnace of a state-of-the-art coal-fired USC boiler with a thermal power of 1,210 MW are presented, which were carried out using the commercial software FLUENT {sup registered} 6.3, combined with some User-Defined Functions. In addition to air combustion, the cases studied include variations of the burner oxygen concentration and the mode of flue gas recycling (wet and dry), the two additional parameters that present themselves in oxycoal combustion to meet the retrofit criteria. The same burner geometry optimised for oxycoal combustion was used in all cases, while the overall boiler geometry designed for air

The influence of the furnace design on emissions from small wood pellet burners

International Nuclear Information System (INIS)

Aspfors, Jonas; Larfeldt, Jenny

1999-01-01

Two pellet burners have been installed and tested in a small scale boiler for house heating. The boiler is representative for the Swedish households and the burners, upwards and forward burning, are commercially available on the Swedish market. This work focuses on the boiler operation and particularly the potential of improved emissions by changing the furnace design. An insulation of the fireplace lowered the emission of CO by 50% and the emission of OGC by 60% for the upwards burning burner at low load. Modifying the furnace using baffles did not have any influence on the emissions. It is concluded that an increased temperature in the furnace is more important than an increased residence time of the combustible gases to decrease the emissions. At full load both burners emit approximately 300 mg CO per nm 3 gas and the emission of OGC are negligible. At half load the emissions of CO increased to 1000 mg/m n 3 and OGC to 125 mg/m n 3 in the upward burning burner. The forwards burning burner had a small increase in OGC to about 10 mg/m n 3 at half load while the emission of CO increased to 800 mg/m n 3 . The forward burning burner is less influenced on the furnace design compared to the upward burning burner. The comparatively high emissions of OGC for the upward burning burner is explained by the intermittent operation. However, it was possible to reduce the emissions from this burner by ceramic insulation of the furnace Project report from the program: Small scale combustion of biofuels. 3 refs, 12 figs, 2 tab, 1 appendix with 33 figs and 12 tabs

Characteristics of premixed flames stabilized in an axisymmetric curved-wall jet burner with tip modification

KAUST Repository

Kim, Daejoong; Gil, Y. S.; Chung, TaeWon; Chung, Suk-Ho

2009-01-01

The stabilization characteristics of premixed flames in an axisymmetric curved-wall jet burner have been experimentally investigated. This burner utilized the Coanda effect on top of a burner tip. The initially spherical burner tip was modified to a

DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL

Energy Technology Data Exchange (ETDEWEB)

Larry G. Felix; P. Vann Bush

2002-01-31

This is the fifth Quarterly Technical Report for DOE Cooperative Agreement No. DE-FC26-00NT40895. A statement of the project objectives is included in the Introduction of this report. One additional biomass co-firing test burn was conducted during this quarter. In this test (Test 9), up to 20% by weight dry hardwood sawdust and switchgrass was injected through the center of the single-register burner with Jacobs Ranch coal. Jacobs Ranch coal is a low-sulfur Powder River Basin coal ({approx} 0.5% S). The results from Test 9 as well as for Test 8 (conducted late last quarter) are presented in this quarterly report. Significant progress has been made in implementing a modeling approach to combine reaction times and temperature distributions from computational fluid dynamic models of the pilot-scale combustion furnace with char burnout and chemical reaction kinetics to predict NO{sub x} emissions and unburned carbon levels in the furnace exhaust. Additional results of CFD modeling efforts have been received and preparations are under way for continued pilot-scale combustion experiments with the dual-register burner. Finally, a project review was held at NETL in Pittsburgh, on November 13, 2001.

Rosebud SynCoal Partnership, SynCoal{reg_sign} demonstration technology update

Energy Technology Data Exchange (ETDEWEB)

Sheldon, R.W. [Rosebud SynCoal Partnership, Billings, MT (United States)

1997-12-31

An Advanced Coal Conversion Process (ACCP) technology being demonstrated in eastern Montana (USA) at the heart of one of the world`s largest coal deposits is providing evidence that the molecular structure of low-rank coals can be altered successfully to produce a unique product for a variety of utility and industrial applications. The product is called SynCoal{reg_sign} and the process has been developed by the Rosebud SynCoal Partnership (RSCP) through the US Department of Energy`s multi-million dollar Clean Coal Technology Program. The ACCP demonstration process uses low-pressure, superheated gases to process coal in vibrating fluidized beds. Two vibratory fluidized processing stages are used to heat and convert the coal. This is followed by a water spray quench and a vibratory fluidized stage to cool the coal. Pneumatic separators remove the solid impurities from the dried coal. There are three major steps to the SynCoal{reg_sign} process: (1) thermal treatment of the coal in an inert atmosphere, (2) inert gas cooling of the hot coal, and (3) removal of ash minerals. When operated continuously, the demonstration plant produces over 1,000 tons per day (up to 300,000 tons per year) of SynCoal{reg_sign} with a 2% moisture content, approximately 11,800b Btu/lb and less than 1.0 pound of SO{sub 2} per million Btu. This product is obtained from Rosebud Mine sub-bituminous coal which starts with 25% moisture, 8,600 Btu/lb and approximately 1.6 pounds of SO{sub 2} per million Btu.

Feasibility of applying coal-fired boiler technology to process heaters

Energy Technology Data Exchange (ETDEWEB)

O' Sullivan, T F

1978-01-01

The preponderance of coal in US fossil fuel reserves has raised the question of the conversion of hydrocarbon process heaters to coal firing. A review undertaken in 1977 by an API sub-committee concluded that neither existing heaters nor existing heater designs were capable of modification or revision to burn coal, and that new coal-fired design consistent with process requirements would be needed for this purpose. In recognition of this need a cooperative investigation was undertaken by Combustion Engineering and Lummus. The present paper, reporting on this investigation, reviews existing coal-fired boiler equipment and techniques and describes their adaptation to the development of a design concept for a coal-fired process heater. To this end, the design parameters for both steam boilers and fired heaters have been compared and have been incorporated into a workable coal-fired process heater design which includes the following features; a coutant bottom for ash removal, an ash-hopper located under both radiant and convection chambers, a tangent type finned wall construction, a straight through gas flow pattern, a vertical tube convection section, horizontal firing using round burners, and an overall geometry allowing a coil arrangement capable of accommodating varying numbers of parallel serpentine coils. These features are integrated into a conceptual heater design which is detailed in a series of illustrations.

Measurements and simulation for design optimization for low NOx coal-firing system

Energy Technology Data Exchange (ETDEWEB)

E. Bar-Ziv; Y. Yasur; B. Chudnovsky; L. Levin; A. Talanker [Ben-Gurion University of Negev, Beer-Sheva (Israel)

2003-07-01

The information required to design a utility steam generator is the heat balance, fuel analysis and emission. These establish the furnace wall configuration, the heat release rates, and the firing technology. The furnace must be sized for (1) residence time for complete combustion with low NOx, and (2) reduction of flue gas temperature to minimize ash deposition. To meet these, computational fluid dynamics (CFD) of the combustion process in the furnace were performed and proven to be a powerful tool for this purpose. Still, reliable numerical simulations require careful interpretation and comparison with measurements. We report numerical results and measurements for a 575 MW pulverized coal tangential firing boiler of the Hadera power plant of Israel Electric Corporation (IEC). Measured and calculated values were found to be in reasonable agreement. We used the simulations for optimization and investigated temperature distribution, heat fluxes and concentration of chemical species. We optimized both the furnace flue gas temperature entering the convective path and the staged residence time for low NOx. We tested mass flow rates through close-coupled and separate overfire air ports and its arrangement and the coal powder fineness. These parameters can control the mixing rate between the fuel and the oxidizer streams and can affect the most important characteristics of the boiler such as temperature regimes, coal burning rate and nitrogen oxidation/reduction. From this effort, IEC started to improve the boiler performance by replacing the existing typical tangential burners to low NOx firing system to ensure the current regulation requirements of emission pollutions.

Process development report: 0.40-m primary burner system

International Nuclear Information System (INIS)

Young, D.T.

1978-04-01

Fluidized bed combustion is required in reprocessing the graphite-based fuel elements from high-temperature gas-cooled reactor (HTGR) cores. This burning process requires combustion of beds containing both large particles and very dense particles, and also of fine graphite particles which elutriate from the bed. This report documents the successful long-term operation of the 0.40-m primary burner in burning crushed fuel elements. The 0.40-m system operation is followed from its first short heatup test in September 1976 to a > 40-h burning campaign that processed 20 LHTGR blocks in September 1977. The 0.40-m perforated conical gas distributor, scaled up from the 0.20-m primary burner, has proven reliable in safely burning even the largest, densest adhered graphite/fuel particle clusters originating from the crushing of loaded fuel elements. Such clusters had never been fed to the 0.20-m system. Efficient combustion of graphite fines using the pressurized recycle technique was demonstrated throughout the long-duration operation required to reduce a high carbon fresh feed bed to a low carbon particle bed. Again, such operation had never been completed on the 0.20-m system from which the 0.40-m burner was scaled. The successful completion of the tests was due, in part, to implementation of significant equipment revisions which were suggested by both the initial 0.40-m system tests and by results of ongoing development work on the 0.2-m primary burner. These revisions included additional penetrations in the burner tube side-wall for above-bed fines recycle, replacement and deletion of several metal bellows with bellows of more reliable design, and improvements in designs for burner alignment and feeder mechanisms. 76 figures, 8 tables

Process development report: 0.20-m primary burner system

International Nuclear Information System (INIS)

Rickman, W.S.

1978-09-01

HTGR reprocessing consists of crushing the spent fuel elements to a size suitable for burning in a fluidized bed to remove excess graphite, separating the fissile and fertile particles, crushing and burning the SiC-coated fuel particles to remove the remainder of the carbon, dissolution and separation of the particles from insoluble materials, and solvent extraction separation of the dissolved uranium and thorium. Burning the crushed fuel elements is accomplished in a primary burner. This is a batch-continuous, fluidized-bed process utilizing above-bed gravity fines recycle. In gas-solid separation, a combination of a cyclone and porous metal filters is used. This report documents operational tests performed on a 0.20-m primary burner using crushed fuel representative of both Fort St. Vrain and large high-temperature gas-cooled reactor cores. The burner was reconstructed to a gravity fines recycle mode prior to beginning these tests. Results of two separate and successful 48-hour burner runs and several short-term runs have indicated the operability of this concept. Recommendations are made for future work

Slurry burner for mixture of carbonaceous material and water

Science.gov (United States)

Nodd, D.G.; Walker, R.J.

1985-11-05

The present invention is intended to overcome the limitations of the prior art by providing a fuel burner particularly adapted for the combustion of carbonaceous material-water slurries which includes a stationary high pressure tip-emulsion atomizer which directs a uniform fuel into a shearing air flow as the carbonaceous material-water slurry is directed into a combustion chamber, inhibits the collection of unburned fuel upon and within the atomizer, reduces the slurry to a collection of fine particles upon discharge into the combustion chamber, and regulates the operating temperature of the burner as well as primary air flow about the burner and into the combustion chamber for improved combustion efficiency, no atomizer plugging and enhanced flame stability.

Development of strand burner for solid propellant burning rate studies

International Nuclear Information System (INIS)

Aziz, A; Mamat, R; Ali, W K Wan

2013-01-01

It is well-known that a strand burner is an apparatus that provides burning rate measurements of a solid propellant at an elevated pressure in order to obtain the burning characteristics of a propellant. This paper describes the facilities developed by author that was used in his studies. The burning rate characteristics of solid propellant have be evaluated over five different chamber pressures ranging from 1 atm to 31 atm using a strand burner. The strand burner has a mounting stand that allows the propellant strand to be mounted vertically. The strand was ignited electrically using hot wire, and the burning time was recorded by electronic timer. Wire technique was used to measure the burning rate. Preliminary results from these techniques are presented. This study shows that the strand burner can be used on propellant strands to obtain accurate low pressure burning rate data

Effects of Burner Configurations on the Natural Oscillation Characteristics of Laminar Jet Diffusion Flames

Directory of Open Access Journals (Sweden)

K. R. V. Manikantachari

2015-09-01

Full Text Available In this work, effects of burner configurations on the natural oscillations of methane laminar diffusion flames under atmospheric pressure and normal gravity conditions have been studied experimentally. Three regimes of laminar diffusion flames, namely, steady, intermittent flickering and continuous flickering have been investigated. Burner configurations such as straight pipe, contoured nozzle and that having an orifice plate at the exit have been considered. All burners have the same area of cross section at the exit and same burner lip thickness. Flame height data has been extracted from direct flame video using MATLAB. Shadowgraph videos have been captured to analyze the plume width characteristics. Results show that, the oscillation characteristics of the orifice burner is significantly different from the other two burners; orifice burner produces a shorter flame and wider thermal plume width in the steady flame regime and the onset of the oscillation/flickering regimes for the orifice burner occurs at a higher fuel flow rate. In the natural flickering regime, the dominating frequency of flame flickering remains within a small range, 12.5 Hz to 15 Hz, for all the burners and for all fuel flow rates. The time-averaged flame length-scale parameters, such as the maximum and the minimum flame heights, increase with respect to the fuel flow rate, however, the difference in the maximum and the minimum flame heights remains almost constant.

Development of a multi-fuel burner for operation with light oil, natural gas and low calorific value gas; Entwicklung eines Mehrstoffbrenners fuer Heizoel-, Erdgas- und Schwachgasbetrieb

Energy Technology Data Exchange (ETDEWEB)

Giese, Anne; Tali, Eren [Gas- und Waerme-Institut Essen e.V., Essen (Germany)

2013-08-15

In the course of the AiF research project 'Development of a multi-fuel burner for operation with natural gas, light oil and low calorific value gas (MSB)' (IGF Grant No. 16202 N), various burner concepts based on the principle of continuously staged air were developed, analysed by means of computational fluid dynamics, built, investigated experimentally and finally tested at a real biomass gasifier (plant). This article describes the results of this research project. (orig.)

The acoustic response of burner-stabilised flat flames : a two-dimensional numerical analysis

NARCIS (Netherlands)

Rook, R.; Goey, de L.P.H.

2003-01-01

The response of burner-stabilized flat flames to acoustic perturbations is studied numerically. So far, one-dimensional models have been used to study this system. However, in most practical surface burners, the scale of the perforations in the burner plate is of the order of the flame thickness.

Environmental Assessment for the Commercial Demonstration of the Low NOx Burner/Separated Over-Fire Air (LNB/SOFA) Integration System Emission Reduction Technology, Finney County, Kansas

Energy Technology Data Exchange (ETDEWEB)

n/a

2003-03-11

The U.S. Department of Energy (DOE) proposes to provide partial funding to the Sunflower Electric Power Corporation (Sunflower), to demonstrate the commercial application of Low-NO{sub x} Burner/Separated Over-Fire Air (LNB/SOFA) integration system to achieve NO{sub x} emission reduction to the level of 0.15 to 0.22 pounds per million British thermal units (lb/MM Btu). The proposed project station is Sunflower's 360 MW coal-fired generation station, Holcomb Unit No. 1 (Holcomb Station). The station, fueled by coal from Wyoming's Powder River Basin, is located near Garden City, in Finney County, Kansas. The period of performance is expected to last approximately 2 years. The Holcomb Station, Sunflower LNB/SOFA integrated system would be modified in three distinct phases to demonstrate the synergistic effect of layering NO{sub x} control technologies. Once modified, the station would demonstrate that a unit equipped with an existing low-NO{sub x} burner system can be retrofitted with a new separated over-fire air (SOFA) system, coal flow measurement and control, and enhanced combustion monitoring to achieve about 45 percent reduction in nitrogen oxides (NO{sub x}) emissions. The proposed project would demonstrate a technology alternative to Selective Catalytic Reduction (SCR) systems. While SCR does generally achieve high reductions in NO{sub x} emissions (from about 0.8 lb/MM to 0.12 lb/MM Btu), it does so at higher capital and operating cost, requires the extensive use of critical construction labor, requires longer periods of unit outage for deployment, and generally requires longer periods of time to complete shakedown and full-scale operation. Cost of the proposed project technology would be on the order of 15-25 percent of that for SCR, with consequential benefits derived from reductions in construction manpower requirements and periods of power outages. This proposed technology demonstration would generally be applicable to boilers using opposed

HIGH PRESSURE COAL COMBUSTON KINETICS PROJECT

Energy Technology Data Exchange (ETDEWEB)

Stefano Orsino

2005-03-30

As part of the U.S. Department of Energy (DoE) initiative to improve the efficiency of coal-fired power plants and reduce the pollution generated by these facilities, DOE has funded the High-Pressure Coal Combustion Kinetics (HPCCK) Projects. A series of laboratory experiments were conducted on selected pulverized coals at elevated pressures with the specific goals to provide new data for pressurized coal combustion that will help extend to high pressure and validate models for burnout, pollutant formation, and generate samples of solid combustion products for analyses to fill crucial gaps in knowledge of char morphology and fly ash formation. Two series of high-pressure coal combustion experiments were performed using SRI's pressurized radiant coal flow reactor. The first series of tests characterized the near burner flame zone (NBFZ). Three coals were tested, two high volatile bituminous (Pittsburgh No.8 and Illinois No.6), and one sub-bituminous (Powder River Basin), at pressures of 1, 2, and 3 MPa (10, 20, and 30 atm). The second series of experiments, which covered high-pressure burnout (HPBO) conditions, utilized a range of substantially longer combustion residence times to produce char burnout levels from 50% to 100%. The same three coals were tested at 1, 2, and 3 MPa, as well as at 0.2 MPa. Tests were also conducted on Pittsburgh No.8 coal in CO2 entrainment gas at 0.2, 1, and 2 MPa to begin establishing a database of experiments relevant to carbon sequestration techniques. The HPBO test series included use of an impactor-type particle sampler to measure the particle size distribution of fly ash produced under complete burnout conditions. The collected data have been interpreted with the help of CFD and detailed kinetics simulation to extend and validate devolatilization, char combustion and pollutant model at elevated pressure. A global NOX production sub-model has been proposed. The submodel reproduces the performance of the detailed chemical

A small porous-plug burner for studies of combustion chemistry and soot formation

Science.gov (United States)

Campbell, M. F.; Schrader, P. E.; Catalano, A. L.; Johansson, K. O.; Bohlin, G. A.; Richards-Henderson, N. K.; Kliewer, C. J.; Michelsen, H. A.

2017-12-01

We have developed and built a small porous-plug burner based on the original McKenna burner design. The new burner generates a laminar premixed flat flame for use in studies of combustion chemistry and soot formation. The size is particularly relevant for space-constrained, synchrotron-based X-ray diagnostics. In this paper, we present details of the design, construction, operation, and supporting infrastructure for this burner, including engineering attributes that enable its small size. We also present data for charactering the flames produced by this burner. These data include temperature profiles for three premixed sooting ethylene/air flames (equivalence ratios of 1.5, 1.8, and 2.1); temperatures were recorded using direct one-dimensional coherent Raman imaging. We include calculated temperature profiles, and, for one of these ethylene/air flames, we show the carbon and hydrogen content of heavy hydrocarbon species measured using an aerosol mass spectrometer coupled with vacuum ultraviolet photoionization (VUV-AMS) and soot-volume-fraction measurements obtained using laser-induced incandescence. In addition, we provide calculated mole-fraction profiles of selected gas-phase species and characteristic profiles for seven mass peaks from AMS measurements. Using these experimental and calculated results, we discuss the differences between standard McKenna burners and the new miniature porous-plug burner introduced here.

Developement of porous media burner operating on waste vegetable oil

International Nuclear Information System (INIS)

Lapirattanakun, Arwut; Charoensuk, Jarruwat

2017-01-01

Highlights: • Steam was successfully applied to promote combustion of WVO. • A specially designed porous domain was an essential element for stable combustion of WVO. • The performance of WVO burner was in the range of cooking stove. • Nozzle clog up in domestic WVO burner can be avoided when replacing it with a steam-assisted nozzle. - Abstract: A newly designed cooking stove using Wasted Vegetable Oil (WVO) as fuel was introduced. Porous media, containing 2 cm diameter of spherical ceramic balls, was used as a flame stabilizer. Steam was successfully applied in a burner at this scale to atomize WVO droplet and entrain air into the combustion zone as well as to reduce soot and CO emission. DIN EN 203-1 testing standard was adopted and the experiment was conducted at various firing rate with the water flow rate at 0.16, 0.20 and 0.22 kg/min. Temperature, emissions, visible flame length, thermal efficiency as well as combustion efficiency were evaluated. Under the current WVOB design, it was suitable to operate the burner at the range of nominal firing rate between 325 and 548 kW/m"2 with water flow rate of 0.16 kg/min, at burner height to diameter ratio of 0.75, giving CO and NO_x emissions up to 171 and 40 ppm, respectively (at 6% O_2). Thermal efficiency was at around 28% where the combustion efficiency was approximately at 99.5%. The performance of WVO burner could be improved further if increasing the H/D ratio to 1.5, yielding thermal efficiency up to 42%.

Non-uniform velocity profile mechanism for flame stabilization in a porous radiant burner

Energy Technology Data Exchange (ETDEWEB)

Catapan, R.C.; Costa, M. [Mechanical Engineering Department, Instituto Superior Tecnico, Technical University of Lisbon, Avenida Rovisco Pais, 1049-001 Lisbon (Portugal); Oliveira, A.A.M. [Mechanical Engineering Department, Federal University of Santa Catarina, Campus Universitario Professor Joao David Ferreira Lima, 88040-900 Florianopolis, SC (Brazil)

2011-01-15

Industrial processes where the heating of large surfaces is required lead to the possibility of using large surface porous radiant burners. This causes additional temperature uniformity problems, since it is increasingly difficult to evenly distribute the reactant mixture over a large burner surface while retaining its stability and keeping low pollutant emissions. In order to allow for larger surface area burners, a non-uniform velocity profile mechanism for flame stabilization in a porous radiant burner using a single large injection hole is proposed and analyzed for a double-layered burner operating in open and closed hot (laboratory-scale furnace, with temperature-controlled, isothermal walls) environments. In both environments, local mean temperatures within the porous medium have been measured. For lower reactant flow rate and ambient temperature the flame shape is conical and anchored at the rim of the injection hole. As the volumetric flow rate or furnace temperature is raised, the flame undergoes a transition to a plane flame stabilized near the external burner surface. However, the stability range envelope remains the same in both regimes. (author)

Variability of Mercury Content in Coal Matter From Coal Seams of The Upper Silesia Coal Basin

Science.gov (United States)

Wierzchowski, Krzysztof; Chećko, Jarosław; Pyka, Ireneusz

2017-12-01

The process of identifying and documenting the quality parameters of coal, as well as the conditions of coal deposition in the seam, is multi-stage and extremely expensive. The taking and analyzing of seam samples is the method of assessment of the quality and quantity parameters of coals in deep mines. Depending on the method of sampling, it offers quite precise assessment of the quality parameters of potential commercial coals. The main kind of seam samples under consideration are so-called "documentary seam samples", which exclude dirt bands and other seam contaminants. Mercury content in coal matter from the currently accessible and exploited coal seams of the Upper Silesian Coal Basin (USCB) was assessed. It was noted that the mercury content in coal seams decreases with the age of the seam and, to a lesser extent, seam deposition depth. Maps of the variation of mercury content in selected lithostratigraphic units (layers) of the Upper Silesian Coal Basin have been created.

The Influence Of Calcite On The Ash Flow Temperature For Semi-Anthracite Coal From Donbas District

Directory of Open Access Journals (Sweden)

Čarnogurská Mária

2014-12-01

Full Text Available This paper presents the results of research focused on the lowering of ash flow temperature at semianthracite coal from Donbas district by means of additive (calcite dosing. Ash fusion temperatures were set for two coal samples (A, B and for five various states (samples of ash without any additives, with 1%, with 3%, with 5% and with 7% of the additive in total. The macroscopicphotographic method was used for identifying all specific temperatures. Obtained outputs prove that A type coal has a lower value of sphere temperature than B type coal in the whole scope of percentage representation of the additive. The flow temperature dropped in total from 1489 °C to 1280 °C, i.e. by 14% during the test of coal of type A with 7% of the additive; while it was near 10% for coal of type B (from 1450 °C to 1308 °C. Numerical simulations of the process showed that it is not effective to add an additive with a grain size lower than 280 μm by means of wastevapour burners.

Industrial applications of Tenova FlexyTech flame-less low NOx burners

International Nuclear Information System (INIS)

Fantuzzi, M.; Ballarino, L.

2008-01-01

Environmental emissions constraints have led manufacturers to improve their low NO x recuperative burners. The development by Tenova of the FlexyTech Flame-less burners with low NO x emissions, even below the present 'Best Available Technology' limit of 40 ppm at 3% O 2 with furnace temperature 1250 C, air preheat 450 C, is described. The results achieved during the R and D programme have been also improved in the industrial installations. Some details and performances of the recent furnaces equipped with such burners are provided. (authors)

Steam coal processing technology: handling, high-order processing, COM, meth-coal

Energy Technology Data Exchange (ETDEWEB)

Kamata, H.; Onodera, J.

1982-01-01

Topics covered include: various handling techologies (overland and marine transport, storage, water removal, drying, comminution and sizing); various coal processing technologies (gravity concentration, magnetic separation, multi-stage flotation, liquid-phase pelletizing, chemical processing); production methods for coal-oil mixtures (COM), their physical properties, stability, storage, transport, advantages, plus recent trends in research and development; production of coal-methanol slurry (meth-coal), its stability, storage, transport, utilization and environmental problems, plus latest trends in research and development. (In Japanese)

The release of nitrogen in coal combustion and pyrolysis

International Nuclear Information System (INIS)

Varey, J.E.; Hindmarsh, C.J.; Thomas, K.M.

1994-01-01

Environmental aspects of coal utilization are a major concern. Recent advances in the development of low NO x burners and the emerging technologies of fluidized bed combustion have led to the identification of coal char nitrogen as the major contributor to the nitrogen oxides released during combustion. The temperature programmed combustion and pyrolysis of a series of coals covering a wide range of rank have been investigated. In addition, maceral concentrates have been investigated to assess the variation in the combustion behavior and the release of nitrogen in the pyrolysis and combustion of macerals. This investigation has involved the use of thermogravimetric analysis - mass spectrometry (TG-MS) with two sampling options: (1) ∼1cm from the sample and (2) at the exit of the TG. The former allows reactive species to be identified in the combustion of the coals. These temperature programmed combustion results have been compared with similar measurements carried out at the exit of the TG where the products are at equilibrium. In addition, pyrolysis studies have been carried out under similar conditions. The results show that reactive intermediate species such as HCN, (CN) 2 , COS etc. can be detected in the combustion products. The evolution of these species during combustion are compared with the pyrolysis products of the coal. The results are discussed in relation to the structure of the coals and the conversion of volatile species and char nitrogen to nitrogen oxides

The application of zonal trademark combustion monitoring and tuning system to coal boilers for efficiency improvement and emissions reduction

Energy Technology Data Exchange (ETDEWEB)

Xu, Guang; Zhou, Wei; Widmer, Neil C.; Moyeda, David K. [GE Energy, Irvine, CA (United States)

2013-07-01

Coal-fired boilers equipped with Low NO{sub x} Burner (LNB) and Overfire Air (OFA) are challenged with maintaining good combustion conditions. In many cases, the significant increases in carbon monoxide (CO) and unburned carbon levels can be attributed to local poor combustion conditions as a result of poorly controlled fuel-air distribution within the furnace. The Zonal trademark combustion monitoring and tuning system developed by GE is available to detect and correct the furnace air-fuel distribution imbalance. The system monitors the boiler excess oxygen (O{sub 2}) and combustible gases, primarily carbon monoxide (CO), by using spatially distributed multipoint sensors located in the boiler's high temperature upper convective backpass region. At these locations, the furnace flow is still significantly stratified allowing tracing of poor combustion zones to specific burners and OFA ports. Using a model-based tuning system, operators can rapidly respond to poor combustion conditions by redistributing airflows to select burners and OFA ports. By improving combustion at every point within the furnace, the boiler can operate at reduced excess O{sub 2} and reduced furnace exit gas temperature (FEGT) while also reducing localized hot spots, corrosive gas conditions, slag formation, and carbon-in-ash. Benefits include improving efficiency, reducing NO{sub X} emissions, increasing output and maximizing availability. This chapter presents the results from implementing the Zonal combustion monitoring and tuning system on a 460 MW tangential-fired coal boiler in the Western United States.

Exploratory Research on Novel Coal

Energy Technology Data Exchange (ETDEWEB)

Winschel, R.A.; Brandes, S.D.

1998-05-01

The report presents the findings of work performed under DOE Contract No. DE-AC22 -95PC95050, Task 3 - Flow Sheet Development. A novel direct coal liquefaction technology was investigated in a program being conducted by CONSOL Inc. with the University of Kentucky Center for Applied Energy Research and LDP Associates. The process concept explored consists of a first-stage coal dissolution step in which the coal is solubilized by hydride ion donation. In the second stage, the products are catalytically upgraded to refinery feedstocks. Integrated first-stage and solids-separation steps were used to prepare feedstocks for second-stage catalytic upgrading. An engineering and economic evaluation was conducted concurrently with experimental work throughout the program. Parameters were established for a low-cost, low-severity first-stage reaction system. A hydride ion reagent system was used to effect high coal conversions of Black Thunder Mine Wyoming subbituminous coal. An integrated first-stage and filtration step was successfully demonstrated and used to produce product filtrates with extremely low solids contents. High filtration rates previously measured off-line in Task 2 studies were obtained in the integrated system. Resid conversions of first-stage products in the second stage were found to be consistently greater than for conventional two-stage liquefaction resids. In Task 5, elementally balanced material balance data were derived from experimental results and an integrated liquefaction system balance was completed. The economic analysis indicates that the production of refined product (gasoline) via this novel direct liquefaction technology is higher than the cost associated with conventional two-stage liquefaction technologies. However, several approaches to reduce costs for the conceptual commercial plant were recommended. These approaches will be investigated in the next task (Task 4) of the program.

China's coal policy since 1979: A brief overview

International Nuclear Information System (INIS)

Shen Lei; Gao Tianming; Cheng Xin

2012-01-01

Since reform and opening-up in 1978, the coal industry in China has been developing rapidly. This article identified major factors affecting the growth of China's coal industry, immediate targets, economic policies, as well as structural reforms of the sector. Authors have divided its developing process into three stages: rapid growth of coal industry (1979–1992); close-down of small-scale coal mines (SCMs) (1993–2001); resource consolidation (2002–present). At the first stage, led by the ‘two-leg walking’ strategy, SCMs grew significantly, which eased the pressure of energy shortage. From the transition of planned economy to market economy, major state-owned coal mines (MSCs), which were not consistently profitable, would have to learn how to withstand severe competitions and survive. As a result, the central government took several measures to try to keep them alive. This situation was not changed until 2001. Large-scaled coal mine groups were then established by the government when China entered the WTO. MSCs were encouraged to merge with others to form a certain scale, as a way to compete with giant overseas. So a trial was firstly implemented in Shanxi province. - Highlights: ► Authors have divided the China coal developing process since 1979 into three stages. ► Some polices solve main problems in that stage, but it also lead to another matters in following stage. ► China coal industry need to establish large coal mine groups to compete with overseas coal giants. ► Environmental and safe policy will significantly affect coal industrial development in the future.

Influence of Cu(NO32 initiation additive in two-stage mode conditions of coal pyrolytic decomposition

Directory of Open Access Journals (Sweden)

Larionov Kirill

2017-01-01

Full Text Available Two-stage process (pyrolysis and oxidation of brown coal sample with Cu(NO32 additive pyrolytic decomposition was studied. Additive was introduced by using capillary wetness impregnation method with 5% mass concentration. Sample reactivity was studied by thermogravimetric analysis with staged gaseous medium supply (argon and air at heating rate 10 °C/min and intermediate isothermal soaking. The initiative additive introduction was found to significantly reduce volatile release temperature and accelerate thermal decomposition of sample. Mass-spectral analysis results reveal that significant difference in process characteristics is connected to volatile matter release stage which is initiated by nitrous oxide produced during copper nitrate decomposition.

Innovative clean coal technology: 500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NOx) emissions from coal-fired boilers. Final report, Phases 1 - 3B

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-01-01

This report presents the results of a U.S. Department of Energy (DOE) Innovative Clean Coal Technology (ICCT) project demonstrating advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NOx) emissions from coal-fired boilers. The project was conducted at Georgia Power Company`s Plant Hammond Unit 4 located near Rome, Georgia. The technologies demonstrated at this site include Foster Wheeler Energy Corporation`s advanced overfire air system and Controlled Flow/Split Flame low NOx burner. The primary objective of the demonstration at Hammond Unit 4 was to determine the long-term effects of commercially available wall-fired low NOx combustion technologies on NOx emissions and boiler performance. Short-term tests of each technology were also performed to provide engineering information about emissions and performance trends. A target of achieving fifty percent NOx reduction using combustion modifications was established for the project. Short-term and long-term baseline testing was conducted in an {open_quotes}as-found{close_quotes} condition from November 1989 through March 1990. Following retrofit of the AOFA system during a four-week outage in spring 1990, the AOFA configuration was tested from August 1990 through March 1991. The FWEC CF/SF low NOx burners were then installed during a seven-week outage starting on March 8, 1991 and continuing to May 5, 1991. Following optimization of the LNBs and ancillary combustion equipment by FWEC personnel, LNB testing commenced during July 1991 and continued until January 1992. Testing in the LNB+AOFA configuration was completed during August 1993. This report provides documentation on the design criteria used in the performance of this project as it pertains to the scope involved with the low NOx burners and advanced overfire systems.

MA-burners efficiency parameters allowing for the duration of transmutation process

International Nuclear Information System (INIS)

Gulevich, A.; Zemskov, E.; Kalugin, A.; Ponomarev, L.; Seliverstov, V.; Seregin, M.

2010-01-01

Transmutation of minor actinides (MA) means their transforming into the fission products. Usually, MA-burner's transmutation efficiency is characterized by the static parameters only, such as the number of neutrons absorbed and the rate of MA feeding. However, the proper characterization of MA-burner's efficiency additionally requires the consideration of parameters allowing for the duration of the MA transmutation process. Two parameters of that kind are proposed: a) transmutation time τ - mean time period from the moment a mass of MA is loaded into the burner's fuel cycle to be transmuted to the moment this mass is completely transmuted; b) number of reprocessing cycles n rep - effective number of reprocessing cycles a mass of loaded MA has to undergo before being completely transmuted. Some of MA-burners' types have been analyzed from the point of view of these parameters. It turned out that all of them have the value of parameters too high from the practical point of view. It appears that some new approaches to MA-burner's design have to be used to significantly reduce the value of these parameters in order to make the large-scale MA transmutation process practically reasonable. Some of such approaches are proposed and their potential efficiency is discussed. (authors)

CFD optimization of a pellet burner

Directory of Open Access Journals (Sweden)

Westerlund Lars B.

2012-01-01

Full Text Available Increased capacity of computers has made CFD technology attractive for the design of different apparatuses. Optimization of a pellet burner using CFD was investigated in this paper. To make the design tool work fast, an approach with only mixing of gases was simulated. Other important phenomena such as chemical reactions were omitted in order to speed up the design process. The original design of the burner gave unsatisfactory performance. The optimized design achieved from simulation was validated and the results show a significant improvement. The power output increased and the emission of unburned species decreased but could be further reduced. The contact time between combustion gases and secondary air was probably too short. An increased contact time in high temperature conditions would possibly improve the design further.

Modeling and optimization of processes for clean and efficient pulverized coal combustion in utility boilers

Directory of Open Access Journals (Sweden)

Belošević Srđan V.

2016-01-01

Full Text Available Pulverized coal-fired power plants should provide higher efficiency of energy conversion, flexibility in terms of boiler loads and fuel characteristics and emission reduction of pollutants like nitrogen oxides. Modification of combustion process is a cost-effective technology for NOx control. For optimization of complex processes, such as turbulent reactive flow in coal-fired furnaces, mathematical modeling is regularly used. The NOx emission reduction by combustion modifications in the 350 MWe Kostolac B boiler furnace, tangentially fired by pulverized Serbian lignite, is investigated in the paper. Numerical experiments were done by an in-house developed three-dimensional differential comprehensive combustion code, with fuel- and thermal-NO formation/destruction reactions model. The code was developed to be easily used by engineering staff for process analysis in boiler units. A broad range of operating conditions was examined, such as fuel and preheated air distribution over the burners and tiers, operation mode of the burners, grinding fineness and quality of coal, boiler loads, cold air ingress, recirculation of flue gases, water-walls ash deposition and combined effect of different parameters. The predictions show that the NOx emission reduction of up to 30% can be achieved by a proper combustion organization in the case-study furnace, with the flame position control. Impact of combustion modifications on the boiler operation was evaluated by the boiler thermal calculations suggesting that the facility was to be controlled within narrow limits of operation parameters. Such a complex approach to pollutants control enables evaluating alternative solutions to achieve efficient and low emission operation of utility boiler units. [Projekat Ministarstva nauke Republike Srbije, br. TR-33018: Increase in energy and ecology efficiency of processes in pulverized coal-fired furnace and optimization of utility steam boiler air preheater by using in

Effect of fuel volatility on performance of tail-pipe burner

Science.gov (United States)

Barson, Zelmar; Sargent, Arthur F , Jr

1951-01-01

Fuels having Reid vapor pressures of 6.3 and 1.0 pounds per square inch were investigated in a tail-pipe burner on an axial-flow-type turbojet engine at a simulated flight Mach number of 0.6 and altitudes from 20,000 to 45,000 feet. With the burner configuration used in this investigation, having a mixing length of only 8 inches between the fuel manifold and the flame holder, the low-vapor-pressure fuel gave lower combustion efficiency at a given tail-pipe fuel-air ratio. Because the exhaust-nozzle area was fixed, the lower efficiency resulted in lower thrust and higher specific fuel consumption. The maximum altitude at which the burner would operate was practically unaffected by the change in fuel volatility.

Two-stage coal liquefaction without gas-phase hydrogen

Science.gov (United States)

Stephens, H.P.

1986-06-05

A process is provided for the production of a hydrogen-donor solvent useful in the liquefaction of coal, wherein the water-gas shift reaction is used to produce hydrogen while simultaneously hydrogenating a donor solvent. A process for the liquefaction of coal using said solvent is also provided. The process enables avoiding the use of a separate water-gas shift reactor as well as high pressure equipment for liquefaction. 3 tabs.

The influence of burner material properties on the acoustical transfer function of radiant surface burners

NARCIS (Netherlands)

Schreel, K.R.A.M.; Tillaart, van den E.L.; Goey, de L.P.H.

2005-01-01

Modern central heating systems use low NO$_x$ premixed burners with a largemodulation range. This can lead to noise problems which cannot be solved viatrial and error, but need accurate modelling. An acoustical analysis as part ofthe design phase can reduce the time-to-market considerably, but the

Experimental Research on the Impactive Dynamic Effect of Gas-Pulverized Coal of Coal and Gas Outburst

Directory of Open Access Journals (Sweden)

Haitao Sun

2018-03-01

Full Text Available Coal and gas outburst is one of the major serious natural disasters during underground coal, and the shock air flow produced by outburst has a huge threat on the mine safety. In order to study the two-phase flow of a mixture of pulverized coal and gas of a mixture of pulverized coal and gas migration properties and its shock effect during the process of coal and gas outburst, the coal samples of the outburst coal seam in Yuyang Coal Mine, Chongqing, China were selected as the experimental subjects. By using the self-developed coal and gas outburst simulation test device, we simulated the law of two-phase flow of a mixture of pulverized coal and gas in the roadway network where outburst happened. The results showed that the air in the roadway around the outburst port is disturbed by the shock wave, where the pressure and temperature are abruptly changed. For the initial gas pressure of 0.35 MPa, the air pressure in different locations of the roadway fluctuated and eventually remain stable, and the overpressure of the outburst shock wave was about 20~35 kPa. The overpressure in the main roadway and the distance from the outburst port showed a decreasing trend. The highest value of temperature in the roadway increased by 0.25 °C and the highest value of gas concentration reached 38.12% during the experiment. With the action of shock air flow, the pulverized coal transportation in the roadway could be roughly divided into three stages, which are the accelerated movement stage, decelerated movement stage and the particle settling stage respectively. Total of 180.7 kg pulverized coal of outburst in this experiment were erupted, and most of them were accumulated in the main roadway. Through the analysis of the law of outburst shock wave propagation, a shock wave propagation model considering gas desorption efficiency was established. The relationships of shock wave overpressure and outburst intensity, gas desorption rate, initial gas pressure, cross

Development of stoker-burner wood chip combustion systems for the UK market

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-07-01

The document makes a case for the development of a design of wood chip stoker-burner more suited to the UK than those currently imported from Sweden and Finland. The differences would centre on market conditions, performance and cost-effectiveness and the devices would be manufactured or part-manufactured in the UK. Econergy Limited was contracted by the DTI as part of its Sustainable Energy Programmes to design and construct an operational prototype stoker-burner rated at 120 kWth. A test rig was built to: (i) study modified burner heads and (ii) develop control hardware and a control strategy. Both (i) and (ii) are described. Tests brought about an increase in performance of the burner head and its wet wood performance. It was considered that further improvements are achievable and six areas for future study were suggested.

MA-burners efficiency parameters allowing for the duration of transmutation process

Energy Technology Data Exchange (ETDEWEB)

Gulevich, A.; Zemskov, E. [Institute of Physics and Power Engineering, Bondarenko Square 1, Obninsk, Kaluga Region 249020 (Russian Federation); Kalugin, A.; Ponomarev, L. [Russian Research Center ' ' Kurchatov Institute' ' Kurchatov Square 1, Moscow 123182 (Russian Federation); Seliverstov, V. [Institute of Theoretical and Experimental Physics ul.B. Cheremushkinskaya 25, Moscow 117259 (Russian Federation); Seregin, M. [Russian Research Institute of Chemical Technology Kashirskoe Shosse 33, Moscow 115230 (Russian Federation)

2010-07-01

Transmutation of minor actinides (MA) means their transforming into the fission products. Usually, MA-burner's transmutation efficiency is characterized by the static parameters only, such as the number of neutrons absorbed and the rate of MA feeding. However, the proper characterization of MA-burner's efficiency additionally requires the consideration of parameters allowing for the duration of the MA transmutation process. Two parameters of that kind are proposed: a) transmutation time {tau} - mean time period from the moment a mass of MA is loaded into the burner's fuel cycle to be transmuted to the moment this mass is completely transmuted; b) number of reprocessing cycles n{sub rep} - effective number of reprocessing cycles a mass of loaded MA has to undergo before being completely transmuted. Some of MA-burners' types have been analyzed from the point of view of these parameters. It turned out that all of them have the value of parameters too high from the practical point of view. It appears that some new approaches to MA-burner's design have to be used to significantly reduce the value of these parameters in order to make the large-scale MA transmutation process practically reasonable. Some of such approaches are proposed and their potential efficiency is discussed. (authors)

CFD simulations on marine burner flames

DEFF Research Database (Denmark)

Cafaggi, Giovanni; Jensen, Peter Arendt; Glarborg, Peter

The marine industry is changing with new demands concerning high energy efficiency, fuel flexibility and lower emissions of NOX and SOX. A collaboration between the company Alfa Laval and Technical University of Denmark has been established to support the development of the next generation...... of marine burners. The resulting auxiliary boilers shall be compact and able to operate with different fuel types, while reducing NOX emissions. The specific boiler object of this study uses a swirl stabilized liquid fuel burner, with a pressure swirl spill-return atomizer (Fig.1). The combustion chamber...... is enclosed in a water jacket used for water heating and evaporation, and a convective heat exchanger at the furnace outlet super-heats the steam. The purpose of the present study is to gather detailed knowledge about the influence of fuel spray conditions on marine utility boiler flames. The main goal...

Next Generation Pressurized Oxy-Coal Combustion: High Efficiency and No Flue Gas Recirculation

Energy Technology Data Exchange (ETDEWEB)

Rue, David

2013-09-30

The Gas Technology Institute (GTI) has developed a pressurized oxy-coal fired molten bed boiler (MBB) concept, in which coal and oxygen are fired directly into a bed of molten coal slag through burners located on the bottom of the boiler and fired upward. Circulation of heat by the molten slag eliminates the need for a flue gas recirculation loop and provides excellent heat transfer to steam tubes in the boiler walls. Advantages of the MBB technology over other boilers include higher efficiency (from eliminating flue gas recirculation), a smaller and less expensive boiler, modular design leading to direct scalability, decreased fines carryover and handling costs, smaller exhaust duct size, and smaller emissions control equipment sizes. The objective of this project was to conduct techno-economic analyses and an engineering design of the MBB project and to support this work with thermodynamic analyses and oxy-coal burner testing. Techno-economic analyses of GTI’s pressurized oxy-coal fired MBB technology found that the overall plant with compressed CO2 has an efficiency of 31.6%. This is a significant increase over calculated 29.2% efficiency of first generation oxy-coal plants. Cost of electricity (COE) for the pressurized MBB supercritical steam power plant with CO2 capture and compression was calculated to be 134% of the COE for an air-coal supercritical steam power plant with no CO2 capture. This compares positively with a calculated COE for first generation oxy-coal supercritical steam power plants with CO2 capture and compression of 164%. The COE for the MBB power plant is found to meet the U.S. Department of Energy (DOE) target of 135%, before any plant optimization. The MBB power plant was also determined to be simpler than other oxy-coal power plants with a 17% lower capital cost. No other known combustion technology can produce higher efficiencies or lower COE when CO2 capture and compression are included. A thermodynamic enthalpy and exergy analysis

Reconstruction of the aero-mixture channels of the pulverized coal plant of the 100MW power plant unit

Directory of Open Access Journals (Sweden)

Ivanovic Vladan B.

2011-01-01

Full Text Available After the last revitalization of thermal power block of 100 MW in TPP “Kostolac A”, made in the year 2004, during the operation of the plant, pulverized coal deposition often occurred in horizontal sections of the aero-mixture channels. Deposition phenomenon manifested itself in places ahead of spherical compensators in the direction of flow of pulverized coal to the burners, due to unfavorable configuration of these channels. Coal dust deposited in the channels dried and spontaneously combusted, causing numerous damage to channels and its isolation as well as the frequent stoppage of the operation for necessary interventions. The paper presents the original solution of reconstruction of aero-mixture channels which prevented deposition of coal dust and its eventual ignition. In this way the reliability of the mill plant is maximized and higher availability of boiler and block as a whole is achieved.

Incineration of ion exchange resins using concentric burners

International Nuclear Information System (INIS)

Fukasawa, T.; Chino, K.; Kawamura, F.; Kuriyama, O.; Yusa, H.

1985-01-01

A new incineration method, using concentric burners, is studied to reduce the volume of spent ion exchange resins generated from nuclear power plants. Resins are ejected into the center of a propane-oxygen flame and burned within it. The flame length is theoretically evaluated by the diffusion-dominant model. By reforming the burner shape, flame length can be reduced by one-half. The decomposition ratio decreases with larger resin diameters due to the loss of unburned resin from the flame. A flame guide tube is adapted to increase resin holding time in the flame, which improves the decomposition ratio to over 98 wt%

BURNER RIG TESTING OF A500 C/SiC

Science.gov (United States)

2018-03-17

AFRL-RX-WP-TR-2018-0071 BURNER RIG TESTING OF A500® C /SiC Larry P. Zawada Universal Technology Corporation Jennifer Pierce UDRI...TITLE AND SUBTITLE BURNER RIG TESTING OF A500® C /SiC 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62102F 6...test program characterized the durability behavior of A500® C /SiC ceramic matrix composite material at room and elevated temperature. Specimens were

Indian coal industry: Growth perspective

International Nuclear Information System (INIS)

Sachdev, R.K.

1993-01-01

Growth perspective of Indian coal industry and their environmental aspects, are discussed. The complete coal chain comprises of mining including preparation and processing, transport, usage and disposal of solid, liquid and gaseous wastes. Proper environmental protection measures are therefore, required to be integrated at every stage. At mining stage, land reclamation, restoration of surface damaged by subsidence and proper treatment of effluents are the minimum requirement for effective environmental protection. Since coal will continue to be the major source of commercial energy in coming decades initiative will have to be taken in making coal a clean fuel from the point of view of its usage in different industries. Washing of high ash coals for reducing the ash content will go a long way in reducing the atmospheric pollution through better plant performance and reduced environmental pollution at the power plants. (author)

Advanced In-Furnace NOx Control for Wall and Cyclone-Fired Boilers

International Nuclear Information System (INIS)

Sarv, Hamid

2009-01-01

A NO x minimization strategy for coal-burning wall-fired and cyclone boilers was developed that included deep air staging, innovative oxygen use, reburning, and advanced combustion control enhancements. Computational fluid dynamics modeling was applied to refine and select the best arrangements. Pilot-scale tests were conducted by firing an eastern high-volatile bituminous Pittsburgh No.8 coal at 5 million Btu/hr in a facility that was set up with two-level overfire air (OFA) ports. In the wall-fired mode, pulverized coal was burned in a geometrically scaled down version of the B and W DRB-4Z(reg sign) low-NO x burner. At a fixed overall excess air level of 17%, NO x emissions with single-level OFA ports were around 0.32 lb/million Btu at 0.80 burner stoichiometry. Two-level OFA operation lowered the NO x levels to 0.25 lb/million Btu. Oxygen enrichment in the staged burner reduced the NO x values to 0.21 lb/million Btu. Oxygen enrichment plus reburning and 2-level OFA operation further curbed the NO x emissions to 0.19 lb/million Btu or by 41% from conventional air-staged operation with single-level OFA ports. In the cyclone firing arrangement, oxygen enrichment of the cyclone combustor enabled high-temperature and deeply staged operation while maintaining good slag tapping. Firing the Pittsburgh No.8 coal in the optimum arrangement generated 112 ppmv NO x (0.15 lb/million Btu) and 59 ppmv CO. The optimum emissions results represent 88% NO x reduction from the uncontrolled operation. Levelized costs for additional NO x removal by various in-furnace control methods in reference wall-fired or cyclone-fired units already equipped with single-level OFA ports were estimated and compared with figures for SCR systems achieving 0.1 lb NO x /10 6 Btu. Two-level OFA ports could offer the most economical approach for moderate NO x control, especially for smaller units. O 2 enrichment in combination with 2-level OFA was not cost effective for wall-firing. For cyclone units

Process development report: 0.20-m secondary burner system

International Nuclear Information System (INIS)

Rickman, W.S.

1977-09-01

HTGR fuel reprocessing consists of crushing the spent fuel elements to a size suitable for burning in a fluidized bed to remove excess graphite; separating, crushing, and reburning the fuel particles to remove the remainder of the burnable carbon; dissolution and separation of the particles from insoluble materials; and solvent extraction separation of the dissolved uranium and thorium. Burning the crushed fuel particles is accomplished in a secondary burner. This is a batch fluidized-bed reactor with in-vessel, off-gas filtration. Process heat is provided by an induction heater. This report documents operational tests performed on a commercial size 0.20-m secondary burner using crushed Fort St. Vrain type TRISO fuel particles. Analysis of a parametric study of burner process variables led to recommending lower bed superficial velocity (0.8 m/s), lower ignition temperature (600 0 C), lower fluid bed operating temperature (850 0 C), lower filter blowback frequency (1 cycle/minute), and a lower fluid bed superficial velocity during final bed burnout

Method and means for cracking oils

Energy Technology Data Exchange (ETDEWEB)

Crozier, R H

1928-05-18

In a retort for the distillation of coal, shale or the like utilizing the heat in vapors drawn off at different stages from the retort to distill off oils of lower boiling point, the arrangement at the lower end of the retort of a flue or a series of flues acting as bracing members and providing for the introduction of a gas burner or gas burners adapted to be supplied with gas from the gas mains of the like or the retort whereby the gas produced may be utilized to the greatest advantage.

Development of combined low-emissions burner devices for low-power boilers

Science.gov (United States)

Roslyakov, P. V.; Proskurin, Yu. V.; Khokhlov, D. A.

2017-08-01

Low-power water boilers are widely used for autonomous heat supply in various industries. Firetube and water-tube boilers of domestic and foreign manufacturers are widely represented on the Russian market. However, even Russian boilers are supplied with licensed foreign burner devices, which reduce their competitiveness and complicate operating conditions. A task of developing efficient domestic low-emissions burner devices for low-power boilers is quite acute. A characteristic property of ignition and fuel combustion in such boilers is their flowing in constrained conditions due to small dimensions of combustion chambers and flame tubes. These processes differ significantly from those in open combustion chambers of high-duty power boilers, and they have not been sufficiently studied yet. The goals of this paper are studying the processes of ignition and combustion of gaseous and liquid fuels, heat and mass transfer and NO x emissions in constrained conditions, and the development of a modern combined low-emissions 2.2 MW burner device that provides efficient fuel combustion. A burner device computer model is developed and numerical studies of its operation on different types of fuel in a working load range from 40 to 100% of the nominal are carried out. The main features of ignition and combustion of gaseous and liquid fuels in constrained conditions of the flame tube at nominal and decreased loads are determined, which differ fundamentally from the similar processes in steam boiler furnaces. The influence of the burner devices design and operating conditions on the fuel underburning and NO x formation is determined. Based on the results of the design studies, a design of the new combined low-emissions burner device is proposed, which has several advantages over the prototype.

Coal fired power plant fireside problems

International Nuclear Information System (INIS)

Mayer, P.; Manolescu, A.V.

1984-01-01

This paper describes the recent experience with fireside problems in coal fired subcritical boilers at Ontario Hydro*, and is concerned with boiler tube wastage. Problems with other components such as burners, air pre-heaters and ''back-end'' ductwork are not discussed. In most utilities, boiler tube failures account for a sizable portion of the total forced outages (typically about25%) as well as a very large part of the maintenance outages. The failures shown under the external deterioration category are of interest because they indicate the proportion of problems caused by the tube metal wastage processes initiated on the fireside of the boilers. Fireside problems remain an important cause of boiler tube failures year after year in spite of concentrated efforts to mitigate them

Pollutant emissions reduction and performance optimization of an industrial radiant tube burner

Energy Technology Data Exchange (ETDEWEB)

Scribano, Gianfranco; Solero, Giulio; Coghe, Aldo [Dipartimento di Energetica, Politecnico di Milano, via La Masa, 34, 20156 Milano (Italy)

2006-07-15

This paper presents the results of an experimental investigation performed upon a single-ended self-recuperative radiant tube burner fuelled by natural gas in the non-premixed mode, which is used in the steel industry for surface treatment. The main goal of the research activity was a systematic investigation of the burner aimed to find the best operating conditions in terms of optimum equivalence ratio, thermal power and lower pollutant emissions. The analysis, which focused on the main parameters influencing the thermal efficiency and pollutant emissions at the exhaust (NO{sub x} and CO), has been carried out for different operating conditions of the burner: input thermal powers from 12.8 up to 18kW and equivalence ratio from 0.5 (very lean flame) to 0.95 (quasi-stoichiometric condition). To significantly reduce pollutant emissions ensuring at the same time the thermal requirements of the heating process, it has been developed a new burner configuration, in which a fraction of the exhaust gases recirculates in the main combustion region through a variable gap between the burner efflux and the inner flame tube. This internal recirculation mechanism (exhaust gases recirculation, EGR) has been favoured through the addition of a pre-combustion chamber terminated by a converging nozzle acting as a mixing/ejector to promote exhaust gas entrainment into the flame tube. The most important result of this solution was a decrease of NO{sub x} emissions at the exhaust of the order of 50% with respect to the original burner geometry, for a wide range of thermal power and equivalence ratio. (author)

Characterization of coal and char reactivity as a function of burn-off

Energy Technology Data Exchange (ETDEWEB)

Biede, O.; Swane Lund, J. [DTU, Dept. of Energy Engineering (Denmark); Holst Soerensen, L. [Risoe National Lab. (Denmark); Peck, R.E. [Arizona State University (United States)

1996-12-01

Four coal types have been tested under varying burning conditions in three high-temperature experimental facilities: A 1.3 MW test furnace, an entrained flow reactor and a down-fired tube furnace with a flat flame burner have been used to produce char samples. More than one hundred partly burned samples with burn-off from 30% to 99% have been collected from the experimental facilities, and analyzed in a thermogravimetric analyser (TGA) giving, besides the proximate data, a char burning profile of each individual sample, using a linear TGA-temperature ramp of 3 deg. C/minute. The burning profile derived by this procedure agrees well with reactivity profiles derived at a constant temperature. It is shown that small particle burn faster than large particles, and that small particles in general are more reactive than large particles. Particles burn faster when the oxygen partial pressure is increased, and apparently the oxygen partial pressure influences the combustion rate differently for different coal types. Except for one coal type, that apparently behaves differently in different burning environments, the ranking with respect to reactivity among the coals remains consistent at both high and at low temperatures. It is further shown how samples from one coal type varies more in behavior than samples from the other coal types, indicating a larger inhomogeneity of this coal. In general the reactivity of collected samples decrease with high-temperature burn-off. (au) 20 refs.

Design and manufacture of an atmospheric burner of biogas with rural application; Diseno y construccion de un quemador atmosferico de biogas con aplicaciones rurales

Energy Technology Data Exchange (ETDEWEB)

Nunez Nunez, Jorge; Suarez Pacheco, Jose; Novelo Navarrete, Jose H; Soto Apolinar, Efrain [Universidad de Quintana Roo, Chetumal, Quintana Roo (Mexico)

2000-07-01

In this text it's resumed the methodology that was carried out to make an atmospheric burner of biogas, as the criteria that were taken in account in order to determine the main parameters of it. It introduces a synthesis of the stages of design and manufacture of the device. The utility of this type of burner increase the efficiency of the oxidation of the biogas compared with the use of conventional burners that aren't designed for this purpose. [Spanish] En este trabajo se resume la metodologia que se llevo a cabo para la construccion de un quemador de biogas tipo atmosferico, asi como los criterios que se tomaron para la determinacion de los parametros principales del mismo. Se presenta una sintesis de las etapas de diseno y manufactura del dispositivo. El uso de este tipo de quemadores aumenta la eficiencia de la oxidacion del biogas en comparacion con el uso de quemadores convencionales que no estan disenados para quemar biogas.

Experimental verification of altitude effect over thermal power in an atmospheric burner

International Nuclear Information System (INIS)

Amell Arrieta, Andres; Agudelo, John Ramiro; Cortes, Jaime

1992-01-01

Colombian national massive gasification plan is carried out in a variety of geographic altitudes ranging from 0 to 2.600 meter. The biggest market is located in the Andinan Region, which is characterized by great urban centres located at high altitudes. Commercial, domestic and industrial applications are characterized by the utilization of appliances using atmospheric burners. The thermal power of these burners is affected by altitude. This paper shows experimental results of thermal power reduction in atmospheric burners due to altitude changes. It was found that thermal power is reduced by 1,5% each 304 meters of altitude

A high turndown, ultra low emission low swirl burner for natural gas, on-demand water heaters

Energy Technology Data Exchange (ETDEWEB)

Rapp, Vi H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Cheng, Robert K. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Therkelsen, Peter L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2017-06-13

Previous research has shown that on-demand water heaters are, on average, approximately 37% more efficient than storage water heaters. However, approximately 98% of water heaters in the U.S. use storage water heaters while the remaining 2% are on-demand. A major market barrier to deployment of on-demand water heaters is their high retail cost, which is due in part to their reliance on multi-stage burner banks that require complex electronic controls. This project aims to research and develop a cost-effective, efficient, ultra-low emission burner for next generation natural gas on-demand water heaters in residential and commercial buildings. To meet these requirements, researchers at the Lawrence Berkeley National Laboratory (LBNL) are adapting and testing the low-swirl burner (LSB) technology for commercially available on-demand water heaters. In this report, a low-swirl burner is researched, developed, and evaluated to meet targeted on-demand water heater performance metrics. Performance metrics for a new LSB design are identified by characterizing performance of current on-demand water heaters using published literature and technical specifications, and through experimental evaluations that measure fuel consumption and emissions output over a range of operating conditions. Next, target metrics and design criteria for the LSB are used to create six 3D printed prototypes for preliminary investigations. Prototype designs that proved the most promising were fabricated out of metal and tested further to evaluate the LSB’s full performance potential. After conducting a full performance evaluation on two designs, we found that one LSB design is capable of meeting or exceeding almost all the target performance metrics for on-demand water heaters. Specifically, this LSB demonstrated flame stability when operating from 4.07 kBTU/hr up to 204 kBTU/hr (50:1 turndown), compliance with SCAQMD Rule 1146.2 (14 ng/J or 20 ppm NOX @ 3% O2), and lower CO emissions than state

IEN project - Fluidized bed burner

International Nuclear Information System (INIS)

1985-08-01

Due to difficulties inherent to the organic waste storage from laboratories and institutes which use radioactive materials for scientific researches, the Nuclear Facilities Division (DIN/CNEN); elaborated a project for constructing a fluidized burner, in laboratory scale, for burning the low level organic radioactive wastes. The burning system of organic wastes is described. (M.C.K.) [pt

Numerical investigation of a novel burner to combust anode exhaust gases of SOFC stacks

Directory of Open Access Journals (Sweden)

Pianko-Oprych Paulina

2017-09-01

Full Text Available The aim of the present study was a numerical investigation of the efficiency of the combustion process of a novel concept burner under different operating conditions. The design of the burner was a part of the development process of a complete SOFC based system and a challenging combination of technical requirements to be fulfilled. A Computational Fluid Dynamics model of a non-premixed burner was used to simulate combustion of exhaust gases from the anode region of Solid Oxide Fuel Cell stacks. The species concentrations of the exhaust gases were compared with experimental data and a satisfactory agreement of the conversion of hydrocarbons was obtained. This validates the numerical methodology and also proves applicability of the developed approach that quantitatively characterized the interaction between the exhaust gases and burner geometry for proper combustion modelling. Thus, the proposed CFD approach can be safely used for further numerical optimisation of the burner design.

Development and demonstration of a gas-fired recuperative confined radiant burner (deliverable 42/43). Final report

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-06-01

The objective of the project was to develop and demonstrate an innovative, efficient, low-pollutant, recuperative gas-fired IR-system (infrared radiation) for industrial processes (hereafter referred to as the CONRAD-system). The CONRAD-system is confined, so flue gases from the combustion can be kept separated from the product. The gas/air mixture to the burner is preheated by means of the flue gas, which increases the radiant efficiency of the CONRAD-system significantly over traditional gas-fired IR burners. During the first phase of the project, the CONRAD-system was designed and developed. The conducted work included a survey on suitable burner materials, modelling of the burner system, basic design of burner construction, control etc., experimental characterisation of several preprototypes and detailed design of the internal heat exchanger in the burner. The result is a cost effective burner system with a documented radiant efficiency up to 66% and low emissions (NO{sub x} and CO) all in accordance with the criteria of success set up at the start of the project. In the second phase of the project, the burner system was established and tested in laboratory and in four selected industrial applications: 1) Drying of coatings on sand cores in the automotive industry. 2) Baking of bread/cake. 3) General purpose painting/powder curing process 4. Curing of powder paint on wood components. The results from the preliminary tests Overe used to optimise the CONRAD-system, before it was applied in the industrial processes and demonstrated. However, the optimised burners manufactured for demonstration suffered from different 'infant failures', which made the installation in an industrial environment very cumbersome, and even impossible in the food industry and the automotive industry. In the latter cases realistic laboratory tests Overe carried out and the established know how reported for use when the burner problems are overcome.(au)

Investigation of air gasification of micronized coal, mechanically activated using the plasma control of the process

Directory of Open Access Journals (Sweden)

Butakov Evgenii

2017-01-01

Full Text Available Combination of the processes of coal combustion and gasification into a single technology of mechano-chemical and plasma-chemical activation is of a considerable scientific and technological interest. Enhancement of coal reactivity at their grinding with mechanical activation is associated with an increase in the reaction rate of carbon material, and at plasma-chemical effect, the main is an increase in reactivity of the oxidizing agent caused by the high plasma temperatures of atomic oxygen. The process of gasification was studied on the 1-MW setup with tangential scroll supply of pulverized coal-air mixture and cylindrical reaction chamber. Coal ground by the standard boiler mill is fed to the disintegrator, then, it is sent to the scroll inlet of the burner-reactor with the transport air. Pulverized coal is ignited by the plasmatron of 10-kW power. In experiments on air gasification of micronized coal, carried out at the temperature in the reaction chamber of 1000-1200°C and air excess α = 0.3-1, the data on CO concentration of 11% and H2 concentration of up to 6% were obtained. Air and air-steam gasification of mechanically-activated micronized coals with plasma control was calculated using SigmaFlow software package.

Investigation of air gasification of micronized coal, mechanically activated using the plasma control of the process

Science.gov (United States)

Butakov, Evgenii; Burdukov, Anatoly; Chernetskiy, Mikhail; Kuznetsov, Victor

2017-10-01

Combination of the processes of coal combustion and gasification into a single technology of mechano-chemical and plasma-chemical activation is of a considerable scientific and technological interest. Enhancement of coal reactivity at their grinding with mechanical activation is associated with an increase in the reaction rate of carbon material, and at plasma-chemical effect, the main is an increase in reactivity of the oxidizing agent caused by the high plasma temperatures of atomic oxygen. The process of gasification was studied on the 1-MW setup with tangential scroll supply of pulverized coal-air mixture and cylindrical reaction chamber. Coal ground by the standard boiler mill is fed to the disintegrator, then, it is sent to the scroll inlet of the burner-reactor with the transport air. Pulverized coal is ignited by the plasmatron of 10-kW power. In experiments on air gasification of micronized coal, carried out at the temperature in the reaction chamber of 1000-1200°C and air excess α = 0.3-1, the data on CO concentration of 11% and H2 concentration of up to 6% were obtained. Air and air-steam gasification of mechanically-activated micronized coals with plasma control was calculated using SigmaFlow software package.

The effects of pf grind quality on coal burnout in a 1 MW combustion test facility

Energy Technology Data Exchange (ETDEWEB)

Richelieu Barranco; Michael Colechin; Michael Cloke; Will Gibb; Edward Lester [University of Nottingham, Nottingham (United Kingdom). School of Chemical, Environmental and Mining Engineering, Nottingham Fuel and Energy Centre

2006-05-15

A study was carried out to determine the effect of pf particle size distribution on coal burnout propensity in a 1 MW pulverised fuel burner. The specific aim of the work was to assess the improvement in combustion performance achievable by retrofitting commercially available high performance static or dynamic classifiers to existing plants. Two coals were used and were selected as representative of extremes in fuel characteristics experienced by coal importing utilities in Europe. Each coal was fired in the unit at a range of grind sizes to determine the overall impact of a variable performance from a mill. The levels of unburnt carbon in the resultant flyashes for the two coals showed significantly different behaviour. For the higher volatile coal, the unburnt carbon was found to be insensitive to grind quality. However, the coarser grinds of the other coal produced significantly lower unburnt carbon than expected when compared with the finest grinds. Generally the results indicate that the installation of improved classification technology, leading to a finer product, will help to lower unburnt carbon levels. Nevertheless, further work will be necessary to establish the levels of diminishing returns for grind size, burnout performance and grind costs. 21 refs., 4 figs., 4 tabs.

Method of burning highly reactive strongly slagging coal dust in a chamber furnace

Energy Technology Data Exchange (ETDEWEB)

Protsaylo, M.Ya.; Kotler, V.R.; Lobov, G.V.; Mechev, V.P.; Proshkin, A.V.; Zhuravlev, Yu.A.

1982-01-01

In the chamber furnace in order to reduce slagging, it is proprosed that, above the coal dust burners, nozzles be installed with inclination downwards through which air is fed in a mixture with flue gases. Under the influence of this flue gas-air mixture, the coal dust flame is deviated downwards. In this case there is an increase in the length of the flame and degree of filling of the volume of the furnace with the flame. This increases the effectiveness of dust burning. The input into the furnace of fuel jointly with the air and flue gases (optimally 10-15% of the total quantity of gases formed during fuel combustion) makes it possible to reduce the temperature in the furnace and the probability of slagging of the furnace walls.

Mathematical model of stacked one-sided arrangement of the burners

Directory of Open Access Journals (Sweden)

Oraz J.A.

2017-01-01

Full Text Available Paper is aimed at computer simulation of the turbulent methane-air combustion in upgraded U-shaped boiler unit. To reduce the temperature in the flame and hence NOx release every burner output was reduced, but the number of the burners was increased. The subject of studying: complex of characteristics with space-time fields in the upgraded steam boiler E-370 with natural circulation. The flare structure, temperature and concentrations were determined computationally.

Effects on NOx and SO2 Emissions during Co-Firing of Coal With Woody Biomass in Air Staging and Reburning

Directory of Open Access Journals (Sweden)

Nihad Hodžić

2018-02-01

Full Text Available Co-firing coal with different types of biomass is increasingly being applied in thermal power plants in Europe. The main motive for the use of biomass as the second fuel in coal-fired power plants is the reduction of CO2 emissions, and related financial benefits in accordance with the relevant international regulations and agreements. Likewise, the application of primary measures in the combustion chamber, which also includes air staging and/or reburning, results in a significant reduction in emission of polluting components of flue gases, in particular NOx emissions. In addition to being efficient and their application to new and future thermoblocks is practically unavoidable, their application and existing conventional combustion chamber does not require significant constructional interventions and is therefore relatively inexpensive. In this work results of experimental research of co-firing coals from Middle Bosnian basin with waste woody biomass are presented. Previously formed fuel test matrix is subjected to pulverized combustion under various temperatures and various technical and technological conditions. First of all it refers to the different mass ratio of fuel components in the mixture, the overall coefficient of excess air and to the application of air staging and/or reburning. Analysis of the emissions of components of the flue gases are presented and discussed. The impact of fuel composition and process temperature on the values of the emissions of components of the flue gas is determined. Additionally, it is shown that other primary measures in the combustion chamber are resulting in more or less positive effects in terms of reducing emissions of certain components of the flue gases into the environment. Thus, for example, the emission of NOx of 989 mg/ measured in conventional combustion, with the simultaneous application of air staging and reburning is reduced to 782 mg/, or by about 21%. The effects of the primary measures

Thermo-Acoustic Properties of a Burner with Axial Temperature Gradient: Theory and Experiment

Directory of Open Access Journals (Sweden)

Béla Kosztin

2013-03-01

Full Text Available This paper presents a model for thermo-acoustic effects in a gas turbine combustor. A quarter-wavelength burner with rectangular cross-section has been built and studied from an experimental and theoretical perspective. It has a premixed methane-air flame, which is held by a bluff body, and spans the width of the burner. The flame is compact, i.e. its length is much smaller than that of the burner. The fundamental mode of the burner is unstable; its frequency and pressure distribution have been measured. The complex pressure reflection coefficients at the upstream and downstream end of the burner were also measured. For the theoretical considerations, we divide the burner into three regions (the cold pre-combustion chamber, the flame region and the hot outlet region, and assume one-dimensional acoustic wave propagation in each region. The acoustic pressure and velocity are assumed continuous across the interface between the precombustion chamber and flame region, and across the interface between the flame region and outlet region. The burner ends are modelled by the measured pressure reflection coefficients. The mean temperature is assumed to have the following profile: uniformly cold and uniformly hot in the pre-combustion chamber and outlet region, respectively, and rising continuously from cold to hot in the flame region. For comparison, a discontinuous temperature profile, jumping directly from cold to hot, is also considered. The eigenfrequencies are calculated, and the pressure distribution of the fundamental mode is predicted. There is excellent agreement with the experimental results. The exact profile of the mean temperature in the flame region is found to be unimportant. This study gives us an experimentally validated Green's function, which is a very useful tool for further theoretical studies.

Coal -98

International Nuclear Information System (INIS)

Sparre, C.

1998-01-01

Energi, Haesselbyverket, has now invested in equipment for burning pellets instead of coal. In Linkoeping wastes of rubber are mixed with coal. Also Soederenergi AB has rebuilt their three coal boilers and replaced 100 % of the coal by peat and wood fuels. Coal is a reserve fuel. Several co-generation plants like Linkoeping, Norrkoeping, Uppsala and Oerebro use both coal and forest fuels. The use of coal is then concentrated to the electricity production. The average price of steam coal imported in Sweden in 1997 was 370 SEK/ton or 10 per cent higher than in 1996. For the world, the average import price fell to 46 USD/ton. The price fall was concentrated to the 4th quarter. The prices have continued to fall during 1998 as a result of the crisis in Asia. All Swedish plants meet their emission limits of dust, SO 2 and NO x given by county administrations or concession boards. The co-generation plants have all some sort of SO 2 -removal system. Mostly used is the wet-dry method. The biggest co-generation plant, Vaesteraas, has newly invested in a ca talytic NO x -cleaning system type SCR, which is reducing the emission level 80-90 %. Most other plants are using low NO x -burners or injection systems type SNCR, based on ammonium or urea, which are reducing the emissions 50-70 %. A positive effect of the recently introduced NO x -duties is a 60 % reduction compared to some years ago, when the duties were introduced. World hard coal production was about 3 800 tons in 1997, a minor increase compared to 1996. The coal demand in the OECD-countries has increased about 1.7 % yearly during the last ten years. The coal share of the energy supply is about 20% in the OECD-countries and 27% in the whole world. Several sources estimate a continuing growth during the next 20 years in spite of an increasing use of natural gas and nuclear power. The reason is a strong demand for electrical power in the Asian countries and the developing countries. However, greater efforts to minimize the

Coal liquefaction in early stage of NEDOL process 1t/d PSU; 1t/d PSU ni okeru ekika shoki hanno ni kansuru kento

Energy Technology Data Exchange (ETDEWEB)

Ikeda, K.; Kawabata, M.; Mochizuki, M.; Imada, K. [Nippon Steel Corp., Tokyo (Japan); Nogami, Y.; Inokuchi, K. [Mitsui SRC Development Co. Ltd., Tokyo (Japan)

1996-10-28

To investigate the behavior of coal liquefaction reaction in early stage as a part of studies on the coal liquefaction characteristics using NEDOL process 1 t/d process supporting unit (PSU), coal slurry sample was taken from the outlet of slurry preheater located in the upflow of liquefaction reactors, and was tested. Tanito Harum coal was used for liquefaction. Preheater was operated under the condition of pressure of 170 kg/cm{sup 2}, gas flow rate of 64 Nm{sup 3}/hr, and at temperature up to 410{degree}C at the outlet, in response to the standard test condition. The slurry sample was discharged into a high temperature separator with temperature of 250{degree}C. Liquefaction was not proceeded at the outlet of preheater. Solid residue yielded around 80%, and liquid yielded around 15%. Gases, CO and CO2, and water yielded also small amount around 3%. The solid sample contained much IOM fraction (tetrahydrofuran-insoluble and ash), and the liquid contained much heavy oil fraction. Hydrogenation was not proceeded, and the hydrogen consumption was very low showing below one-tenth of that at the usual operation. Hydrogen sulfide gas was formed at early stage, which suggested that the change of iron sulfide catalyst occur at early stage of liquefaction. 1 ref., 5 figs., 2 tabs.

Investigation of a high pressure oxy-coal process

Energy Technology Data Exchange (ETDEWEB)

Renz, U. [RWTH Aachen Univ. (Germany). Inst. of Heat and Mass Transfer

2013-07-01

A study was conducted to investigate the feasibility of an oxy-coal process, which is pressurized to a combustion pressure of 80 bar. At that pressure the water-vapor can be separated economically from the CO{sub 2}/H{sub 2}O flue gases, either by nucleate condensation or by condensation on cooled surfaces in condenser heat exchangers at a temperature of about 300 C. The heat of condensation can be recaptured to preheat the boiler feed water. So the number of economizers is drastically reduced compared to a conventional steam cycle. Another interesting feature of the high pressure oxy-coal process is the fact, that low rank coal with high moisture content can be fired. Such a process at a pressure of about 80 bar is currently investigated by Babcock, USA, as the ThermoEnergy Integrated Power System (TIPS) and will be analyzed in the present paper. A known disadvantage of the oxy-coal processes is the large recirculating flue gas stream to control the combustion temperature, and which need large pipes and heavy recirculation fans. This disadvantage could be avoided if instead of flue gas a part of the condensed water from the condenser heat exchangers is recirculated. Within the present study both types of processes have been simulated and for an electric power output of about 220 MW. Furthermore, results of CFD simulations of a pressurized 250 MW combustor with a single swirl burner and flue gas recirculation will be presented.

Coal consumption minimizing by increasing thermal energy efficiency at ROMAG-PROD Heavy Water Plant

International Nuclear Information System (INIS)

Preda, Marius Cristian

2006-01-01

ROMAG-PROD Heavy Water Plant is a large thermal energy consumer using almost all the steam output from ROMAG-TERMO Power Plant - the steam cost weight in the total heavy water price is about 40%. The steam consumption minimizing by modernization of isotopic exchange facilities and engineering development in ROMAG-PROD Heavy Water Plant results in an corresponding decrease of coal amount burned at ROMAG-TERMO boilers. This decrease could be achieved mainly by the followings ways: - Facility wrappings integrity; - High performance heat exchangers; - Refurbished heat insulations; - Modified condenser-collecting pipeline routes; - High performance steam traps; - Heat electric wire. When coal is burned in Power Plant burners to obtain thermal energy, toxic emissions results in flue gases, such as: - CO 2 and NO x with impact on climate warming; - SO 2 which results in ozone layer thinning effect and in acid rain falls. From the value of steam output per burned coal: 1 GCal steam = 1.41 tone steam = 0.86 thermal MW = 1.1911 tones burned coal (lignite), it is obvious that by decreasing the thermal energy consumption provided for ROMAG PROD, a coal amount decrease is estimated at about 45 t/h, or about 394,200 t/year coal, which means about 10% of the current coal consumption at ROMAG-TERMO PP. At the same time, by reducing the burned coal amount, an yearly decrease in emissions into air to about 400,000 tones CO 2 is expected

Experimental investigations and numerical simulations of methane cup-burner flame

Directory of Open Access Journals (Sweden)

Kubát P.

2013-04-01

Full Text Available Pulsation frequency of the cup-burner flame was determined by means of experimental investigations and numerical simulations. Simplified chemical kinetics was successfully implemented into a laminar fluid flow model applied to the complex burner geometry. Our methodical approach is based on the monitoring of flame emission, fast Fourier transformation and reproduction of measured spectral features by numerical simulations. Qualitative agreement between experimental and predicted oscillatory behaviour was obtained by employing a two-step methane oxidation scheme.

Development of advanced air-blown entrained-flow two-stage bituminous coal IGCC gasifier

Directory of Open Access Journals (Sweden)

Abaimov Nikolay A.

2017-01-01

Full Text Available Integrated gasification combined cycle (IGCC technology has two main advantages: high efficiency, and low levels of harmful emissions. Key element of IGCC is gasifier, which converts solid fuel into a combustible synthesis gas. One of the most promising gasifiers is air-blown entrained-flow two-stage bituminous coal gasifier developed by Mitsubishi Heavy Industries (MHI. The most obvious way to develop advanced gasifier is improvement of commercial-scale 1700 t/d MHI gasifier using the computational fluid dynamics (CFD method. Modernization of commercial-scale 1700 t/d MHI gasifier is made by changing the regime parameters in order to improve its cold gas efficiency (CGE and environmental performance, namely H2/CO ratio. The first change is supply of high temperature (900°C steam in gasifier second stage. And the second change is additional heating of blast air to 900°C.

Synthesis of Titanium Dioxide Nanoparticles Using a Double-Slit Curved Wall-Jet Burner

KAUST Repository

Ismail, Mohamed; Mansour, Morkous S.; Memon, Nasir K.; Anjum, Dalaver H.; Chung, Suk-Ho

2016-01-01

A novel double-slit curved wall-jet (DS-CWJ) burner was proposed and utilized for flame synthesis. This burner was comprised of double curved wall-jet nozzles with coaxial slits; the inner slit was for the delivery of titanium tetraisopropoxide

Microjet burners for molecular-beam sources and combustion studies

Science.gov (United States)

Groeger, Wolfgang; Fenn, John B.

1988-09-01

A novel microjet burner is described in which combustion is stabilized by a hot wall. The scale is so small that the entire burner flow can be passed through a nozzle only 0.2 mm or less in diameter into an evacuated chamber to form a supersonic free jet with expansion so rapid that all collisional processes in the jet gas are frozen in a microsecond or less. This burner can be used to provide high-temperature source gas for free jet expansion to produce intense beams of internally hot molecules. A more immediate use would seem to be in the analysis of combustion products and perhaps intermediates by various kinds of spectroscopies without some of the perturbation effects encountered in probe sampling of flames and other types of combustion devices. As an example of the latter application of this new tool, we present infrared emission spectra for jet gas obtained from the combustion of oxygen-hydrocarbon mixtures both fuel-rich and fuel-lean operation. In addition, we show results obtained by mass spectrometric analysis of the combustion products.

Coal: the metamorphosis of an industry

Energy Technology Data Exchange (ETDEWEB)

Jean-Marie Martin-Amouroux

2008-07-01

Coal, a fuel that once dominated the global energy scene, is staging a come-back despite being environmentally dirty. The purpose of the paper is to analyse the return of King Coal to find out whether it is likely to be regain its dominance in the global energy in the future. In analysing the metamorphosis of the coal industry, the paper looks at the historical evolution of the industry and analyses the factors behind the change. The deficiencies of coal's competitors are also analysed. Using a scenario analysis, the future role of coal in the global energy mix is estimated as well. The paper finds that despite the domination of hydrocarbons in the global energy mix, coal has maintained a steady share and in some countries, it remained the main fuel. With the concerns of high-oil prices and peak oil, coal is regaining its domination in the power sector around the world. The industry has reformed and restructured itself to remain competitive. Consequently, it has the possibility of staging a come back as a dominant fuel.

40 CFR 63.6092 - Are duct burners and waste heat recovery units covered by subpart YYYY?

Science.gov (United States)

2010-07-01

... Combustion Turbines What This Subpart Covers § 63.6092 Are duct burners and waste heat recovery units covered by subpart YYYY? No, duct burners and waste heat recovery units are considered steam generating units... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Are duct burners and waste heat...

ASSESSMENT OF THE USE FOR FERTILISATION PURPOSES INCINERATION ASH PELLETS USING GASIFICATION BURNER LESTER

Directory of Open Access Journals (Sweden)

Marzena Gibczyńska

2016-12-01

Full Text Available The use of biomass in system energetics for the purpose of increasing the share of renewable energy sources in the overall energy mix by biomass and coal co-combustion is not an optimal solution in the light of previous experience in Poland. It is appropriate to develop local biomass market for energy purposes as a basis for future distributed energy generation based on biomass. This solution facilitates the use of ash from biomass combustion for plant fertilisation. The present paper concerns the assessment of the use of ash from combustion of pellets in an innovative gasifying pellet burner – LESTER type, for soil fertilisation. The paper presents the analysis of the content of macro- and microelements in ash against the chemical composition of pellets in relation to permissible contents in fertilisers. The content of phosphorus, potassium, calcium and magnesium in bottom and fly ash from combustion of wood pellet and rye straw in LESTER gasifying burner validates the use of this material for soil fertilisation purposes. However, due to low nitrogen content – comparable to that found in soil, the material is not to be considered as fertiliser supplying this macroelement to soil. The analysed bottom ash used for fertilisation meets the conditions set out in the Regulation of the Minister of Environment of 9 September 2002. However, fly ash should be used with considerable caution due to high content of iron, zinc and nickel. The yield of bottom ash is several times higher than that of fly ash, therefore the possibility of its use in the form of mixtures in adequate proportions should be considered.

Development, study and use of GN type high-speed burners

Energy Technology Data Exchange (ETDEWEB)

Pilipenko, R A; Yerinov, A Y

1981-01-01

The design of a tunnel high speed gas burner for thermal, tunnel, and annealing furnaces is described. The use of GN type burners and heat treating processes and annealing of articles allows one to attain high uniformity of heating, to reduce fuel consumption, and to simplify the lining. A high degree of (+ or - f/sup 0/C) heating uniformity and significant (up to 30%) fuel saving was obtained in a heat treatment furnace with a roll-out hearth at the Uralkhimmash plant.

Oil fired boiler/solar tank- and natural gas burner/solar tank-units

DEFF Research Database (Denmark)

Furbo, Simon; Vejen, Niels Kristian; Frederiksen, Karsten Vinkler

1999-01-01

During the last few years new units consisting of a solar tank and either an oil fired boiler or a natural gas burner have been introduced on the Danish market. Three different marketed units - two based on a natural gas burner and one based on an oil fired boiler - have been tested in a heat...

Appraisal of BWR plutonium burners for energy centers

International Nuclear Information System (INIS)

Williamson, H.E.

1976-01-01

The design of BWR cores with plutonium loadings beyond the self-generation recycle (SGR) level is investigated with regard to their possible role as plutonium burners in a nuclear energy center. Alternative plutonium burner approaches are also examined including the substitution of thorium for uranium as fertile material in the BWR and the use of a high-temperature gas reactor (HTGR) as a plutonium burner. Effects on core design, fuel cycle facility requirements, economics, and actinide residues are considered. Differences in net fissile material consumption among the various plutonium-burning systems examined were small in comparison to uncertainties in HTGR, thorium cycle, and high plutonium-loaded LWR technology. Variation in the actinide content of high-level wastes is not likely to be a significant factor in determining the feasibility of alternate systems of plutonium utilization. It was found that after 10,000 years the toxicity of actinide high-level wastes from the plutonium-burning fuel cycles was less than would have existed if the processed natural ores had not been used for nuclear fuel. The implications of plutonium burning and possible future fuel cycle options on uranium resource conservation are examined in the framework of current ERDA estimates of minable uranium resources

A design of steady state fusion burner

International Nuclear Information System (INIS)

Hasegawa, Akira; Hatori, Tadatsugu; Itoh, Kimitaka; Ikuta, Takashi; Kodama, Yuji.

1975-01-01

We present a brief design of a steady state fusion burner in which a continuous burning of nuclear fuel may be achieved with output power of a gigawatt. The laser fusion is proposed to ignite the fuel. (auth.)

Premixed burner experiments: Geometry, mixing, and flame structure issues

Energy Technology Data Exchange (ETDEWEB)

Gupta, A.K.; Lewis, M.J.; Gupta, M. [Univ of Maryland, College Park, MD (United States)] [and others

1995-10-01

This research program is exploring techniques for improved fuel-air mixing, with the aim of achieving combustor operations up to stoichiometric conditions with minimal NO x and maximum efficiency. The experimental studies involve the use of a double-concentric natural gas burner that is operable in either premixed or non-premixed modes, and the system allows systematic variation of equivalence ratio, swirl strength shear length region and flow momentum in each annulus. Flame structures formed with various combinations of swirl strengths, flow throughput and equivalence ratios in premixed mode show the significant impact of swirl flow distribution on flame structure emanating from the mixedness. This impact on flame structure is expected to have a pronounced effect on the heat release rate and the emission of NO{sub x}. Thus, swirler design and configuration remains a key factor in the quest for completely optimized combustion. Parallel numerical studies of the flow and combustion phenomena were carried out, using the RSM and thek-{epsilon} turbulence models. These results have not only indicated the strengths and limitations of CFD in performance and pollutants emission predictions, but have provided guidelines on the size and strength of the recirculation produced and the spatio-temporal structure of the combustion flowfield. The first stage of parametric studies on geometry and operational parameters at Morgan State University have culminated in the completion of a one-dimensional flow code that is integrated with a solid, virtual model of the existing premixed burner. This coupling will provide the unique opportunity to study the impact of geometry on the flowfield and vice-versa, with particular emphasis on concurrent design optimization.

Burnout behaviour of bituminous coals in air-staged combustion conditions

Energy Technology Data Exchange (ETDEWEB)

Kluger, F.; Spliethoff, H.; Hein, K.R.G. [University of Stuttgart, Stuttgart (Germany). Inst. of Process Engineering and Power Plant (IVD)

2001-07-01

In order to determine the influence on burnout by the combustion conditions and the coal preparation, three bituminous coals sold on the world market, from three different locations in Poland, South Africa, and Australia, were studied more closely. For this purpose, the coals were ground in two different particle size ranges, which, besides the influence of the combustion conditions, such a temperature, residence time, and stoichiometry, made it possible to also investigate the impact on burnout by the coal preparation. The experiments were carried out in an electrically heated entrained-flow reactor with a thermal input of 8.5 kW. The parameters for the experiments are wall temperature (1000-1350{degree}C), air ratio (0.6-1.15) and two particle sizes (70% {lt} 75 {mu}m, 90% {lt} 75 {mu}m). The results show that in general, for increasing temperatures, the burnout quality will improve. For the Australian Illawara coal, another outcome is increased NOx emissions. Lowering the air ratio in the reduction zone leads to less NOx emission but to increased unburnt matter in ash. For the smaller particle size fraction, the analysis of the different particle sizes shows an improvement of the burnout without a change in NOx emissions. 10 refs., 10 figs., 2 tabs.

Application of roof radiant burners in large pusher-type furnaces

Directory of Open Access Journals (Sweden)

A. Varga

2009-07-01

Full Text Available The paper deals with the application of roof flat-flame burners in the pusher-type steel slab reheating furnaces, after furnace reconstruction and replacement of conventional torch burners, with the objective to increase the efficiency of radiative heat transfer from the refractory roof to the charge. Based on observations and on measurements of the construction and process parameters under operating conditions, the advantages and disadvantages of indirectly oriented radiant heat transfer are analysed in relation to the heat transfer in classically fired furnaces.

Flame stability and emission characteristics of turbulent LPG IDF in a backstep burner

Energy Technology Data Exchange (ETDEWEB)

S. Mahesh; D.P. Mishra [Indian Institute of Technology, Kanpur (India). Combustion Laboratory, Department of Aerospace Engineering

2008-09-15

The stability characteristics and emissions from turbulent LPG inverse diffusion flame (IDF) in a backstep burner are reported in this paper. The blow-off velocity of turbulent LPG IDF is observed to increase monotonically with fuel jet velocity. In contrast to normal diffusion flames (NDF), the flame in the present IDF burner gets blown out without getting lifted-off from the burner surface. The soot free length fraction, SFLF, defined as the ratio of visible premixing length, H{sub p}, to visible flame length, H{sub f}, is used for qualitative estimation of soot reduction in this IDF burner. The SFLF is found to increase with central air jet velocity indicating the occurrence of extended premixing zone in the vicinity of flame base. Interestingly, the soot free length fraction (SFLF) is found to be correlated well with the newly devised parameter, global momentum ratio. The peak value of EINOX happens to occur closer to stoichiometric overall equivalence ratio. 16 refs., 9 figs.

Research and Development of Natural Draft Ultra-Low Emissions Burners for Gas Appliances

Energy Technology Data Exchange (ETDEWEB)

Therkelsen, Peter [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Cheng, Robert [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sholes, Darren [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2017-08-31

Combustion systems used in residential and commercial cooking appliances must be robust and easy to use while meeting air quality standards. Current air quality standards for cooking appliances are far greater than other stationary combustion equipment. By developing an advanced low emission combustion system for cooking appliances, the air quality impacts from these devices can be reduced. This project adapted the Lawrence Berkeley National Laboratory (LBNL) Ring-Stabilizer Burner combustion technology for residential and commercial natural gas fired cooking appliances (such as ovens, ranges, and cooktops). LBNL originally developed the Ring-Stabilizer Burner for a NASA funded microgravity experiment. This natural draft combustion technology reduces NOx emissions significantly below current SCAQMD emissions standards without post combustion treatment. Additionally, the Ring-Stabilizer Burner technology does not require the assistance of a blower to achieve an ultra-low emission lean premix flame. The research team evaluated the Ring-Stabilizer Burner and fabricated the most promising designs based on their emissions and turndown.

Optimization of pulverised coal combustion by means of CFD/CTA modeling

Directory of Open Access Journals (Sweden)

Filkoski Risto V.

2006-01-01

Full Text Available The objective of the work presented in this paper was to apply a method for handling two-phase reacting flow for prediction of pulverized coal combustion in large-scale boiler furnace and to assess the ability of the model to predict existing power plant data. The paper presents the principal steps and results of the numerical modeling of power boiler furnace with tangential disposition of the burners. The computational fluid dynamics/computational thermal analysis (CFD/CTA approach is utilized for creation of a three-dimensional model of the boiler furnace, including the platen superheater in the upper part of the furnace. Standard k-e model is employed for description of the turbulent flow. Coal combustion is modeled by the mixture fraction/probability density function approach for the reaction chemistry, with equilibrium assumption applied for description of the system chemistry. Radiation heat transfer is computed by means of the simplified P-N model, based on the expansion of the radiation intensity into an orthogonal series of spherical harmonics. Some distinctive results regarding the examined boiler performance in capacity range between 65 and 95% are presented graphically. Comparing the simulation predictions and available site measurements concerning temperature, heat flux and combustion efficiency, a conclusion can be drawn that the model produces realistic insight into the furnace processes. Qualitative agreement indicates reasonability of the calculations and validates the employed sub-models. After the validation and verification of the model it was used to check the combustion efficiency as a function of coal dust sieve characteristics, as well as the impact of burners modification with introduction of over fire air ports to the appearance of incomplete combustion, including CO concentration, as well as to the NOx concentration. The described case and other experiences with CFD/CTA stress the advantages of numerical modeling and

Reactivity of mechanical activated coals for special utilization

Energy Technology Data Exchange (ETDEWEB)

Turcaniova, L.; Kadarova, J.; Imrich, P.; Liptaj, T.; Vidlar, J.; Vasek, J.; Foldyna, F.; Sitek, J.; Balaz, P. [Slovak Academy of Science, Kosice (Slovakia). Inst. of Geotechnology

2004-09-01

The paper presents the coal activation effect as disintegration in the nano-submicron range and destruction carbon structure. The Slovak brown coal activated in planetary mill is characterised by destruction of organic structure of coal. The biggest activation effect connected with the destruction of C-C bonds of sp{sup 3} carbons has been confirmed by {sup 13}C NMR spectroscopy in the chemical structure of humic acids extracted from the coal sample activated for a period of 60 min. The specific surface of humic acids is much smaller then that of mechanically activated sample from which they were extracted. The black Czech coal was activated by two stage disintegration. In the first stage of mechanochemical activation using Grinding Aqueous Caustic Leaching, GACL method, a fine dispersed semiproduct is formed with the size of particles from 2.5 to 9000 nm. The additional disintegration using water jet increases the effect of disintegration in the submicron area of the coal product. The volume distribution maximum achieves in this stage about 60 wt% of 750 nm grains.

Effect of cycled combustion ageing on a cordierite burner plate

International Nuclear Information System (INIS)

Garcia, Eugenio; Gancedo, J. Ramon; Gracia, Mercedes

2010-01-01

A combination of 57 Fe-Moessbauer spectroscopy and X-ray Powder Diffraction analysis has been employed to study modifications in chemical and mechanical stability occurring in a cordierite burner aged under combustion conditions which simulate the working of domestic boilers. Moessbauer study shows that Fe is distributed into the structural sites of the cordierite lattice as Fe 2+ and Fe 3+ ions located mostly at octahedral sites. Ferric oxide impurities, mainly hematite, are also present in the starting cordierite material accounting for ≅40% of the total iron phases. From Moessbauer and X-ray diffraction data it can be deduced that, under the combustion conditions used, new crystalline phases were formed, some of the substitutional Fe 3+ ions existing in the cordierite lattice were reduced to Fe 2+ , and ferric oxides underwent a sintering process which results in hematite with higher particle size. All these findings were detected in the burner zone located in the proximity of the flame and were related to possible chemical reactions which might explain the observed deterioration of the burner material. Research Highlights: →Depth profile analyses used as a probe to understand changes in refractory structure. →All changes take place in the uppermost surface of the burner, close to the flame. →Reduction to Fe 2+ of substitutional Fe 3+ ions and partial cordierite decomposition. →Heating-cooling cycling induces a sintering of the existing iron oxide particles. →Chemical changes can explain the alterations observed in the material microstructure.

Combustion characteristics of porous media burners under various back pressures: An experimental study

Directory of Open Access Journals (Sweden)

Xuemei Zhang

2017-07-01

Full Text Available The porous media combustion technology is an effective solution to stable combustion and clean utilization of low heating value gas. For observing the combustion characteristics of porous media burners under various back pressures, investigating flame stability and figuring out the distribution laws of combustion gas flow and resistance loss, so as to achieve an optimized design and efficient operation of the devices, a bench of foamed ceramics porous media combustion devices was thus set up to test the cold-state resistance and hot-state combustion characteristic of burners in working conditions without back pressures and with two different back pressures. The following results are achieved from this experimental study. (1 The strong thermal reflux of porous media can preheat the premixed air effectively, so the flame can be kept stable easily, the combustion equivalent ratio of porous media burners is lower than that of traditional burners, and its pollutant content of flue gas is much lower than the national standard value. (2 The friction coefficient of foamed ceramics decreases with the increase of air flow rate, and its decreasing rate slows down gradually. (3 When the flow rate of air is low, viscosity is the dominant flow resistance, and the friction coefficient is in an inverse relation with the flow rate. (4 As the flow rate of air increases, inertia is the dominant flow resistance, and the friction coefficient is mainly influenced by the roughness and cracks of foamed ceramics. (5 After the introduction of secondary air, the minimum equivalent ratio of porous media burners gets much lower and its range of equivalent ratio is much larger than that of traditional burners.

Comparison calculations for an accelerator-driven minor actinide burner

International Nuclear Information System (INIS)

2002-01-01

International interest in accelerator-driven systems (ADS) has recently been increasing in view of the important role that these systems may play as efficient minor actinide and long-lived fission-product (LLFP) burners and/or energy producers with an enhanced safety potential. However, the current methods of analysis and nuclear data for minor actinide and LLFP burners are not as well established as those for conventionally fuelled reactor systems. Hence, in 1999, the OECD/NEA Nuclear Science Committee organised a benchmark exercise for an accelerator-driven minor actinide burner to check the performances of reactor codes and nuclear data for ADS with unconventional fuel and coolant. The benchmark model was a lead-bismuth-cooled subcritical system driven by a beam of 1 GeV protons. This report provides an analysis of the results supplied by seven participants from eight countries. The analysis reveals significant differences in important neutronic parameters, indicating a need for further investigation of the nuclear data, especially minor actinide data, as well as the calculation methods. This report will be of particular interest to reactor physicists and nuclear data evaluators developing nuclear systems for nuclear waste management. (authors)

Coking coal consumption of POSCO

International Nuclear Information System (INIS)

Yoo, B.C.

1991-01-01

Pohang Iron and Steel Company Limited (POSCO) was established in 1968. Molten iron was first produced in July 1973 after a 3 year construction period. The long awaited start up of Korea's first integrated steel works provided the momentum for the fast growth of our steel industry. In 1973, the first year of operation, POSCO purchased 770,000 tons of coal from the United States and Australia. The import tonnage was more than doubled in 1976 when we completed the second stage of Pohang Works and has continued to increase reaching 13.1 million tons last year. POSCO's coal consumption will increase one more time next year as the fourth stage of Kwangyang works starts to operate a new blast furnace with an annual molten iron production capacity of 2.8 million tons. Even though the new blast furnace will have the same capacity as the other 3 in Kwangyang, the additional coking coal requirement will be much smaller than the tonnages we needed for the other stages of the works. This paper reports that this is due to the increased use of pulverized coal

Investigation on the transient enthalpy of coal combustion

Energy Technology Data Exchange (ETDEWEB)

Fu, Pei-fang; Wang, Na; Yu, Bo; Zhang, Bin; Liu, Yang; Zhou, Huai-chun [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion

2013-07-01

The transient enthalpy ({Delta}h) of coal/char combustion of the three different coals (including anthracite, bituminous, and lignite) during the process of combustion is determined as a function of burn-off degree by using thermo-gravimetric-differential scanning calorimeter (TG-DSC) simultaneous thermal analyzer, and The error of determining calorific values of coals/chars is less 5% compared the results of TG-DSC with that of an automatic isoperibol calorimeter. It is found that In the initial stage, all the {Delta}h of coals are greater than that of the char pyrolysized from parent coal for many of volatiles contained more a great deal of heat per unit mass oxidized at low temperature, it also imply that coal is more easily ignited than char corresponded; And in the middle stage, all the {Delta}h of coals is lower than that of the char pyrolysized, so the pyrolysized char oxidation can supply much more of thermo-energy per unit mass. {Delta}h are almost a constant when the burn-off degree is equal to between 0.35/0.15 and 0.95/0.85 for ZCY bituminous coal/char and JWY anthracite/char, between 0.35/0.35 and 0.75/0.9 for SLH lignite/char; In the later stage, the {Delta}h of the coal/char decreased with the burn-off degree, it imply that the activity of the coal/char decreases. Therefore, coal pyrolysis changes not only the structure of char, but also the property of release heat; the transient enthalpy of coal/char combustion has been in change with the burn-out degree.

Combustion zone investigation in fuel flexible suspension fired boilers, Experimental

DEFF Research Database (Denmark)

Clausen, Sønnik; Fateev, Alexander; Hvid, Søren Lovmand

velocities for coal-straw flame were mapped by Laser Doppler velocimetry (LDA) in 235 points. High speed IR-camera with water-cooled endoscope optics has been used to grab images of particle flow patterns and dispersion in flames. The IR-camera was also used with a grating spectrometer to measure gas...... velocity measurements for the coal-straw flame show that the simple gas flow field expected for a single burner is smeared out shortly after start of flame due to interaction with other burners....... and to cut measurement costs. All measurements were carried out on a Mitsui-Babcock Low-NOx wall burner at Studstrup power plant, unit 4, Denmark in October and November 2009. Measurements on a pure coal (reference), coal-straw and coal-wood flame have been obtained. Special attention was paid to the coal...

Interim results: fines recycle testing using the 4-inch diameter primary graphite burner

International Nuclear Information System (INIS)

Palmer, W.B.

1975-05-01

The results of twenty-two HTGR primary burner runs in which graphite fines were recycled pneumatically to the 4-inch diameter pilot-plant primary fluidized-bed burner are described. The result of the tests showed that zero fines accumulation can easily be achieved while operating at plant equivalent burn rates. (U.S.)

Concentrations of lithium in Chinese coals

Energy Technology Data Exchange (ETDEWEB)

Sun, Yuzhuang; Li, Yanheng; Zhao, Cunliang; Lin, Mingyue; Wang, Jinxi; Qin, Shenjun [Hebei University of Engineering, Handan (China). Key Laboratory of Resource Exploration Research of Hebei Province

2010-04-15

Lithium is an important energy metal. Its concentrations in coals have been studied by many geologists. Its average content is only 14 mg/kg in the coals of the world. Lithium has never been reported as a coal associated deposit before. In order to study the concentrations in Chinese coals, 159 coal and gangue samples were taken from six coal mines and were determined by ICP-MS and the minerals in the samples were identified by X-ray powder diffraction. The results indicate that the Li contents in the coal samples from the Antaibao Coal Mine have reached the industry grade of coal associated deposits. In Tongxing Coal Mine, Li contents in the coal floor rock samples have reached the industry grade of independent lithium deposits. Main minerals are polylithionite, triphylite, zinnwaldite, lithionite and cookeite, which were transported into the peats. Therefore, lithium enriched is most likely in the synsedimentary stage in both coal mines. Furthermore, a revised average Li content in Chinese coals was given.

Design and evaluation of a porous burner for the mitigation of anthropogenic methane emissions.

Science.gov (United States)

Wood, Susie; Fletcher, David F; Joseph, Stephen D; Dawson, Adrian; Harris, Andrew T

2009-12-15

Methane constitutes 15% of total global anthropogenic greenhouse gas emissions. The mitigation of these emissions could have a significant near-term effect on slowing global warming, and recovering and burning the methane would allow a wasted energy resource to be exploited. The typically low and fluctuating energy content of the emission streams makes combustion difficult; however porous burners-an advanced combustion technology capable of burning low-calorific value fuels below the conventional flammability limit-are one possible mitigation solution. Here we discuss a pilot-scale porous burner designed for this purpose. The burner comprises a cylindrical combustion chamber filled with a porous bed of alumina saddles, combined with an arrangement of heat exchanger tubes for preheating the incoming emission stream. A computational fluid dynamics model was developed to aid in the design process. Results illustrating the burner's stable operating range and behavior are presented: stable ultralean combustion is demonstrated at natural gas concentrations as low as 2.3 vol%, with transient combustion at concentrations down to 1.1 vol%; the system is comparatively stable to perturbations in the operating conditions, and emissions of both carbon monoxide and unburned hydrocarbons are negligible. Based on this pilot-scale demonstration, porous burners show potential as a methane mitigation technology.

Study and mathematical model of ultra-low gas burner

International Nuclear Information System (INIS)

Gueorguieva, A.

2001-01-01

The main objective of this project is prediction and reduction of NOx and CO 2 emissions under levels recommended from European standards for gas combustion processes. A mathematical model of burner and combustion chamber is developed based on interacting fluid dynamics processes: turbulent flow, gas phase chemical reactions, heat and radiation transfer The NOx prediction model for prompt and thermal NOx is developed. The validation of CFD (Computer fluid-dynamics) simulations corresponds to 5 MWI burner type - TEA, installed on CASPER boiler. This burner is three-stream air distribution burner with swirl effect, designed by ENEL to meet future NOx emission standards. For performing combustion computer modelling, FLUENT CFD code is preferred, because of its capabilities to provide accurately description of large number of rapid interacting processes: turbulent flow, phase chemical reactions and heat transfer and for its possibilities to present wide range of calculation and graphical output reporting data The computational tool used in this study is FLUENT version 5.4.1, installed on fs 8200 UNIX systems The work includes: study the effectiveness of low-NOx concepts and understand the impact of combustion and swirl air distribution and flue gas recirculation on peak flame temperatures, flame structure and fuel/air mixing. A finite rate combustion model: Eddy-Dissipation (Magnussen-Hjertager) Chemical Model for 1, 2 step Chemical reactions of bi-dimensional (2D) grid is developed along with NOx and CO 2 predictions. The experimental part of the project consists of participation at combustion tests on experimental facilities located in Livorno. The results of the experiments are used, to obtain better vision for combustion process on small-scaled design and to collect the necessary input data for further Fluent simulations

Passive safety design characteristics of the KALIMER-600 burner reactor

International Nuclear Information System (INIS)

Kwon, Young-Min; Jeong, Hae-Yong; Cho, Chung-Ho; Ha, Ki-Seok; Kim, Sang-Ji

2009-01-01

The Korea Atomic Energy Research Institute (KAERI) has recently studied several burner core designs for a transuranics (TRU) transmutation based on the breakeven core geometry of KALIMER-600. The KALIMER-600 is a net electrical rating of 600MWe, sodium-cooled, metallic-fueled, pool-type reactor. For the burner core concept selected for the present analysis, the smearing fractions of the fuel rods in three fuel zones are changed while maintaining the cladding outer diameter and cladding thickness. The resulting fuel slug smearing fractions of the inner, middle, and outer core zones are 36%, 40%, and 48%, respectively. The TRU conversion ratio is 0.57 and the TRU enrichment of the driver fuel is set to 30.0 w/o because of the current practical limitation of the U-TRU-10%Zr metal fuel database. The purpose of this paper is to evaluate the safety performance characteristics provided by the passive safety design features in the KALIMER-600 burner reactor by using a system-wide safety analysis code. The present scoping analysis focuses on an assessment of the enhanced safety design features that provide passive and self-regulating responses to transient conditions and an evaluation of the safety margin during unprotected overpower, unprotected loss of flow, and unprotected loss of heat sink events. The analysis results show that the KALIMER-600 burner reactor provides larger safety margins with respect to the sodium boiling, fuel rod integrity, and structural integrity. The overall inherent safety can be enhanced by accounting for the reactivity feedback mechanisms in the design process. (author)

Effect of cycled combustion ageing on a cordierite burner plate

Energy Technology Data Exchange (ETDEWEB)

Garcia, Eugenio [Instituto de Ceramica y Vidrio, CSIC, c/ Kelsen 5, Campus de Cantoblanco, 28049 Madrid (Spain); Gancedo, J. Ramon [Instituto de Quimica Fisica ' Rocasolano' , CSIC, c/ Serrano 119, 28006 Madrid (Spain); Gracia, Mercedes, E-mail: rocgracia@iqfr.csic.es [Instituto de Quimica Fisica ' Rocasolano' , CSIC, c/ Serrano 119, 28006 Madrid (Spain)

2010-11-15

A combination of {sup 57}Fe-Moessbauer spectroscopy and X-ray Powder Diffraction analysis has been employed to study modifications in chemical and mechanical stability occurring in a cordierite burner aged under combustion conditions which simulate the working of domestic boilers. Moessbauer study shows that Fe is distributed into the structural sites of the cordierite lattice as Fe{sup 2+} and Fe{sup 3+} ions located mostly at octahedral sites. Ferric oxide impurities, mainly hematite, are also present in the starting cordierite material accounting for {approx_equal}40% of the total iron phases. From Moessbauer and X-ray diffraction data it can be deduced that, under the combustion conditions used, new crystalline phases were formed, some of the substitutional Fe{sup 3+} ions existing in the cordierite lattice were reduced to Fe{sup 2+}, and ferric oxides underwent a sintering process which results in hematite with higher particle size. All these findings were detected in the burner zone located in the proximity of the flame and were related to possible chemical reactions which might explain the observed deterioration of the burner material. Research Highlights: {yields}Depth profile analyses used as a probe to understand changes in refractory structure. {yields}All changes take place in the uppermost surface of the burner, close to the flame. {yields}Reduction to Fe{sup 2+} of substitutional Fe{sup 3+} ions and partial cordierite decomposition. {yields}Heating-cooling cycling induces a sintering of the existing iron oxide particles. {yields}Chemical changes can explain the alterations observed in the material microstructure.

500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide emissions from coal-fired boilers

Energy Technology Data Exchange (ETDEWEB)

Sorge, J.N.; Larrimore, C.L.; Slatsky, M.D.; Menzies, W.R.; Smouse, S.M.; Stallings, J.W.

1997-12-31

This paper discusses the technical progress of a US Department of Energy Innovative Clean Coal Technology project demonstrating advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NOx) emissions from coal-fired boilers. The primary objectives of the demonstration is to determine the long-term NOx reduction performance of advanced overfire air (AOFA), low NOx burners (LNB), and advanced digital control optimization methodologies applied in a stepwise fashion to a 500 MW boiler. The focus of this paper is to report (1) on the installation of three on-line carbon-in-ash monitors and (2) the design and results to date from the advanced digital control/optimization phase of the project.

Ammonia-methane combustion in tangential swirl burners for gas turbine power generation

OpenAIRE

Valera Medina, Agustin; Marsh, Richard; Runyon, Jon; Pugh, Daniel; Beasley, Paul; Hughes, Timothy Richard; Bowen, Philip John

2017-01-01

Ammonia has been proposed as a potential energy storage medium in the transition towards a low-carbon economy. This paper details experimental results and numerical calculations obtained to progress towards optimisation of fuel injection and fluidic stabilisation in swirl burners with ammonia as the primary fuel. A generic tangential swirl burner has been employed to determine flame stability and emissions produced at different equivalence ratios using ammonia–methane blends. Experiments were...

Investigation of combustion and gasification mechanically activated coal fuel of various degrees of metamorphism on the 5-MW heat setup

Directory of Open Access Journals (Sweden)

Butakov Evgenii

2017-01-01

Full Text Available The technology of mechanochemical activation of combustion and gasification of coals is of unquestionable scientific and technical interest; an increase in chemical activity of coals at their mechanically activated grinding is associated with an increase in the rate of reaction of the coal substance. To study the combustion and gasification process, the reactor model with tangential scroll input of coal-air suspension and cylindrical reaction chamber was used at the 5-MW thermal power plant. The experiments were carried out with coals of G and SS grades of the Kuznetsk deposit. Coal, ground after the boiler’s standard mill, is fed by a feeder to the disintegrator; then, it enters the scroll inlet of the reactor burner with transport air. The suspension is ignited by a gas igniting device with the power of 50 kW. In experiments on combustion and gasification of fine coal performed at the temperature in the reaction chamber of 1000-1300°C and air excess α = 0.5-0.7, the data on concentrations of CO and H2 were obtained: for coal of grade G, concentration of H2 was 6.3% and concentration of CO was 15.3%; for coal of SS grade, concentration of H2 was 9.5% and concentration of CO was 15.6%.

Separation of the constituents of coal

Energy Technology Data Exchange (ETDEWEB)

Betrand, M F

1938-12-06

A process is disclosed of separating, by means of dense aqueous solutions, the constituents of coal, isolated by preliminary crushing from each other and/or from barren and carbonaceous shales, comprising the addition to the washing water before treatment or during any stage of the preparation of the coal before separation, or to the dense separating solution of agents improving the wetting of the coal by water.

Clean coal technologies

International Nuclear Information System (INIS)

Aslanyan, G.S.

1993-01-01

According to the World Energy Council (WEC), at the beginning of the next century three main energy sources - coal, nuclear power and oil will have equal share in the world's total energy supply. This forecast is also valid for the USSR which possesses more than 40% of the world's coal resources and continuously increases its coal production (more than 700 million tons of coal are processed annually in the USSR). The stringent environmental regulations, coupled with the tendency to increase the use of coal are the reasons for developing different concepts for clean coal utilization. In this paper, the potential efficiency and environmental performance of different clean coal production cycles are considered, including technologies for coal clean-up at the pre-combustion stage, advanced clean combustion methods and flue gas cleaning systems. Integrated systems, such as combined gas-steam cycle and the pressurized fluidized bed boiler combined cycle, are also discussed. The Soviet National R and D program is studying new methods for coal utilization with high environmental performance. In this context, some basic research activities in the field of clean coal technology in the USSR are considered. Development of an efficient vortex combustor, a pressurized fluidized bed gasifier, advanced gas cleaning methods based on E-beam irradiation and plasma discharge, as well as new catalytic system, are are presented. In addition, implementation of technological innovations for retrofitting and re powering of existing power plants is discussed. (author)

Radiation and convective heat transfer, and burnout in oxy-coal combustion

Energy Technology Data Exchange (ETDEWEB)

J.P. Smart; P. O' Nions; G.S. Riley [RWE npower, Swindon (United Kingdom)

2010-09-15

Measurements of radiative and convective heat transfer, and carbon-in-ash have been taken on the RWEn 0.5 MWth combustion test facility (CTF) firing two different coals under oxy-fuel firing conditions. The two coals fired were a Russian Coal and a South African Coal. Recycle ratios were varied within the range of 65-75% dependent on coal. Furnace exit O{sub 2} values were maintained at 3% and 6% for the majority of tests. Air firing tests were also performed to generate baseline data. The work gives a comprehensive insight into the effect of oxy-fuel combustion on both radiative and convective heat transfer, and carbon-in-ash compared to air under dry simulated recycle conditions. Results have shown peak radiative heat flux values are inversely related to the recycle ratio for the two coals studied. Conversely, the convective heat flux values increase with increasing recycle ratio. It was also observed that the axial position of the peak in radiative heat flux moves downstream away from the burner as recycle ratio is increased. A 'working range' of recycle ratios exists where both the radiative and convective heat fluxes are comparable with air. Carbon-in-ash (CIA) was measured for selected conditions. For air firing of Russian Coal, the CIA for follows and expected trend with CIA decreasing with increasing furnace exit O{sub 2}. The CIA data for the two recycle ratios of 72% and 68% for the same coal show that the CIA values are lower than for air firing for corresponding furnace exit O{sub 2} levels and vary little with the value of furnace exit O{sub 2}. CIA measurements were taken for the South African Coal for a range of recycle ratios at 3% and 6% furnace exit O{sub 2} levels. Results indicate that the CIA values are lower for higher furnace exit O{sub 2}. 32 refs., 11 figs., 1 tab.

Efficient direct coal liquefaction of a premium brown coal catalyzed by cobalt-promoted fumed oxides

Energy Technology Data Exchange (ETDEWEB)

Trautmann, M.; Loewe, A.; Traa, Y. [Stuttgart Univ. (Germany). Inst. of Chemical Technology

2013-11-01

The search for alternatives in the fuel sector is an important technological challenge. An interim solution could be provided by direct coal liquefaction. Hydrogen economy and the lack of an efficient catalyst are the main obstacles for this process. We used a premium German brown coal with a high H/C molar ratio of 1.25 and nanostructured cobalt catalysts to improve the efficiency of direct coal liquefaction. We were able to recover and recycle the catalyst efficiently and reached good brown coal conversions and oil yields with single-stage coal liquefaction. The oil quality observed almost reached that of a conventional crude oil considering higher heating value (HHV), H/C molar ratio and aliphatic content. (orig.)

Experimental investigation and optimisation of burner systems for glass melting ends with regenerative air preheating. Final report; Experimentelle Untersuchung und Optimierung von Brennersystemen fuer Glasschmelzwannen mit regenerativer Luftvorwaermung. Schlussbericht

Energy Technology Data Exchange (ETDEWEB)

Scherello, A.; Flamme, M.; Kremer, H.

2000-02-15

The project comprised experiments on burner systems for glass melting ends with regenerative air preheating for the purpose of optimisation. The experimental set-up was to reflect realistic conditions. In the first stage of the investigations, modern burner systems were installed in a GWI test facility and investigated. [German] Ziel des oben genannten Forschungsvorhabens war die Durchfuehrung experimenteller Untersuchungen von Brennersystemen fuer Glasschmelzwannen mit regenerativer Luftvorwaermung sowie deren Optimierung. Dazu war es notwendig, einen experimentellen Aufbau zu realisieren, mit dessen Hilfe die Stroemungs-, Mischungs- und Umsetzungsphaenomene von Glasschmelzoefen realistisch nachgestellt und aussagekraeftige Untersuchungen durchgefuehrt werden koennen. In einem ersten Untersuchungsschritt wurden moderne Brennerlanzen an der GWI-Versuchsanlage installiert und untersucht. (orig.)

Experimental investigation of combustion instabilities in lean swirl-stabilized partially-premixed flames in single- and multiple-burner setup

Directory of Open Access Journals (Sweden)

Christian Kraus

2016-03-01

Full Text Available In the present work, combustion instabilities of a modular combustor are investigated. The combustor operates with partially premixed, swirl-stabilized flames and can be operated in single- and different multiple-burner setups. The design parameters of the combustor prevent large-scale flame–flame interactions in the multiple-burner arrangements. The objective is to investigate how the interaction of the swirl jets affects the thermoacoustic stability of the combustor. Results of measurements of pressure oscillations and high-speed OH*-chemiluminescence imaging for the single-burner setup and two multiple-burner setups are discussed. Additionally, results of investigations with different flame characteristics are presented. These are achieved by varying the ratio of the mass flow rates through the swirlers of the double-concentric swirl nozzle. Several unstable modes with high pressure amplitudes are observed in the single-burner setup as well as in the multiple-burner setups. Numerical studies of the acoustic behavior of the combustor setups were performed that indicate that the different geometries show similar acoustic behaviors. The results lead to the conclusion that the interaction of the swirl jets in the multiple-burner setups affects the thermoacoustic response spectrum of the flame even in the absence of large-scale flame–flame interactions. Based on the findings in earlier studies, it is concluded that the differences in the flame response characteristics are induced by the reduction of the swirl intensity in the multiple-burner arrangements, which is caused by the exchange of momentum between the adjacent swirl jets.

Nuclear magnetic resonance studies of ancient buried wood-II. Observations on the origin of coal from lignite to bituminous coal

Science.gov (United States)

Hatcher, P.G.; Breger, I.A.; Szeverenyi, N.; Maciel, G.E.

1982-01-01

Coalified logs ranging in age from Late Pennsylvania to Miocene and in rank from lignite B to bituminous coal were analyzed by 13C nuclear magnetic resonance (NMR) utilizing the cross-polarization, magic-angle spinning technique, as well as by infrared spectroscopy. The results of this study indicate that at least three major stages of coalification can be observed as wood gradually undergoes transformation to bituminous coal. The first stage involves hydrolysis and loss of cellulose from wood with retention and differential concentration of the resistant lignin. The second stage involves conversion of the lignin residues directly to coalified wood of lignitic rank, during which the oxygen content of intermediate diagenetic products remains constant as the hydrogen content and the carbon content increases. These changes are thought to involve loss of methoxyl groups, water, and C3 side chains from the lignin. In the third major stage of coalification, the coalified wood increases in rank to subbituminous and bituminous coal; during this stage the oxygen content decreases, hydrogen remains constant, and the carbon content increases. These changes are thought to result from loss of soluble humic acids that are rich in oxygen and that are mobilized during compaction and dewatering. Relatively resistant resinous substances are differentially concentrated in the coal during this stage. The hypothesis that humic acids are formed as mobile by-products of the coalification of lignin and function only as vehicles for removal of oxygen represents a dramatic departure from commonly accepted views that they are relatively low-molecular-weight intermediates formed during the degradation of lignin that then condense to form high-molecular-weight coal structures. ?? 1982.

Study on dynamic multi-objective approach considering coal and water conflict in large scale coal group

Science.gov (United States)

Feng, Qing; Lu, Li

2018-01-01

In the process of coal mining, destruction and pollution of groundwater in has reached an imminent time, and groundwater is not only related to the ecological environment, but also affect the health of human life. Similarly, coal and water conflict is still one of the world's problems in large scale coal mining regions. Based on this, this paper presents a dynamic multi-objective optimization model to deal with the conflict of the coal and water in the coal group with multiple subordinate collieries and arrive at a comprehensive arrangement to achieve environmentally friendly coal mining strategy. Through calculation, this paper draws the output of each subordinate coal mine. And on this basis, we continue to adjust the environmental protection parameters to compare the coal production at different collieries at different stages under different attitude of the government. At last, the paper conclude that, in either case, it is the first arrangement to give priority to the production of low-drainage, high-yield coal mines.

Optimal Switching Control of Burner Setting for a Compact Marine Boiler Design

DEFF Research Database (Denmark)

Solberg, Brian; Andersen, Palle; Maciejowski, Jan M.

2010-01-01

This paper discusses optimal control strategies for switching between different burner modes in a novel compact  marine boiler design. The ideal behaviour is defined in a performance index the minimisation of which defines an ideal trade-off between deviations in boiler pressure and water level...... approach is based on a generalisation of hysteresis control. The strategies are verified on a simulation model of the compact marine boiler for control of low/high burner load switches.  ...

Duct burners in heat recovery system for cogeneration and captive power plants

International Nuclear Information System (INIS)

Majumdar, J.

1992-01-01

Our oil explorations both onshore and offshore have thrown open bright prospects of cogeneration by using natural gas in gas turbine power plants with heat recovery units. Both for co-gen and combined cycle systems, supplementary firing of GT exhaust gas is normally required. Hence, duct burners have significant role for effective contribution towards of efficacy of heat recovery system for gas turbine exhaust gas. This article details on various aspects of duct burners in heat recovery systems. (author)

On Bunsen Burners, Bacteria and the Bible

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 2. On Bunsen Burners, Bacteria and the Bible. Milind Watve. Classroom Volume 1 Issue 2 February 1996 pp 84-89. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/001/02/0084-0089 ...

Hydrogeological and groundwater modeling studies to estimate the groundwater inflows into the coal Mines at different mine development stages using MODFLOW, Andhra Pradesh, India

Directory of Open Access Journals (Sweden)

L. Surinaidu

2014-09-01

Full Text Available The Singareni Collieries Company Ltd (SCCL is exploiting coal in the Godavari valley coal fields spread over 5.33 km2 in Andhra Pradesh, India. In the area, six workable coal seams have been identified in Barakar formation by the analysis of the geologic logs of 183 bore wells. A finite difference based numerical groundwater flow model is developed with twenty conceptual layers and with a total thickness of 320 m. The flow model was calibrated under steady state conditions and predicted groundwater inflows into the mine pits at different mine development stages. The groundwater budget results revealed that the mining area would receive net groundwater inflows of 5877 m3 day−1, 12,818 m3 day−1, 12,910 m3 day−1, 20,428 m3 day−1, 22,617 m3 day−1 and 14,504 m3 day−1 at six mine development stages of +124 m (amsl, +93 m (amsl, +64 m (amsl, +41 m (amsl, +0 m (amsl and −41 m (amsl, respectively. The results of the study can be used to plan optimal groundwater pumping and the possible locations to dewater the groundwater for safe mining at different mine development stages.

Coal exports still growing

International Nuclear Information System (INIS)

Blain, M.

1998-01-01

It is shown that the swings and roundabouts of the Asian economic shake out and Australian dollar devaluation are starting to work their way through the Australian export coal market. Perhaps somewhat surprisingly, at this stage the results are not proving to be as bad as were at first predicted by some market watchers. Export revenue and tonnages are up 12% for the year to July 98. Coal exports totaling $9.5 billion left Australia's shores in the 12 months confirming coal as Australia's single largest export revenue earner. Sales volumes in the present financial year are still increasing, the market being driven by steadily increasing Asian demand for steaming coal from places like Korea, Malaysia, Thailand and the Philippines

Preliminary Results on the Effects of Distributed Aluminum Combustion Upon Acoustic Growth Rates in a Rijke Burner

OpenAIRE

Newbold, Brian R.

1998-01-01

Distributed particle combustion in solid propellant rocket motors may be a significant cause of acoustic combustion instability. A Rijke burner has been developed as a tool to investigate the phenomenon. Previous improvements and characterization of the upright burner lead to the addition of a particle injection flame. The injector flame increases the burner's acoustic driving by about 10% which is proportional to the injector's additional 2 g/min of gas. Frequency remained fairly constant fo...

Coal liquefaction becomes viable

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-11-15

In 2003 the May/June issue of CoalTrans International speculated that coal liquefaction would become viable due to falling coal prices. This has not proved the case but the sustained high oil price is sparking new interest. A survey by Energy Intelligence and Marketing Research during November 2005 revealed a growth in the number of projects under development or at the feasibility stage. The article reports projects in China, the USA, Australia, New Zealand, the Philippines and India. China is commissioning the first wave of large liquefaction plants. The key question is whether other countries, particularly the USA, will follow.

Low NOx combustion and SCR flow field optimization in a low volatile coal fired boiler.

Science.gov (United States)

Liu, Xing; Tan, Houzhang; Wang, Yibin; Yang, Fuxin; Mikulčić, Hrvoje; Vujanović, Milan; Duić, Neven

2018-08-15

Low NO x burner redesign and deep air staging have been carried out to optimize the poor ignition and reduce the NO x emissions in a low volatile coal fired 330 MW e boiler. Residual swirling flow in the tangentially-fired furnace caused flue gas velocity deviations at furnace exit, leading to flow field unevenness in the SCR (selective catalytic reduction) system and poor denitrification efficiency. Numerical simulations on the velocity field in the SCR system were carried out to determine the optimal flow deflector arrangement to improve flow field uniformity of SCR system. Full-scale experiment was performed to investigate the effect of low NO x combustion and SCR flow field optimization. Compared with the results before the optimization, the NO x emissions at furnace exit decreased from 550 to 650 mg/Nm³ to 330-430 mg/Nm³. The sample standard deviation of the NO x emissions at the outlet section of SCR decreased from 34.8 mg/Nm³ to 7.8 mg/Nm³. The consumption of liquid ammonia reduced from 150 to 200 kg/h to 100-150 kg/h after optimization. Copyright © 2018. Published by Elsevier Ltd.

Coal 99; Kol 99

Energy Technology Data Exchange (ETDEWEB)

Sparre, C

2000-07-01

in equipment for burning pellets instead of coal. In Linkoeping waste of rubber is mixed with coal. Also Soederenergi AB has rebuilt their three coal boilers and replaced 100 % of the coal by peat and wood fuels. Coal is a reserve fuel. Several co-generation plants like Linkoeping, Norrkoeping, Uppsala and Oerebro use both coal and forest fuels. The use of coal is then concentrated to the electricity production. The average price of steam coal imported in Sweden in 1998 was 370 SEK/ton or the same as in 1997. For the world, the average import price fell about 6 USD/ton to 32 USD/ton. The price fall was concentrated to the 4th quarter. The prices have continued to fall during 1999 as a result of the crisis in Asia but are now stabilising as a result of increasing oil prices. All Swedish plants meet their emission limits of dust, SO{sub 2} and NO{sub x}, given by county administrations or concession boards. The co-generation plants have all some sort of SO{sub 2}-removal system. Mostly used is the wet-dry method. The biggest co-generation plant, in Vaesteraas, has recently invested in a catalytic NO{sub x}-cleaning system type SCR, which is reducing the emission level 80-90 %. Most other plants are using low NO{sub x}- burners or injection systems type SNCR, based on ammonium or urea, which are reducing the emissions 50-70 %. A positive effect of the recently introduced NO{sub x}-duties is a 60 % reduction compared to some years ago, when the duties were introduced. World hard coal production was about 3 700 tons in 1998, a minor decrease compared to 1997. The trade, however, has increased about 3 % to 520 mill tons. The coal demand in the OECD-countries has increased about 1,7 % yearly during the last ten years. The coal share of the energy supply is about 20% in the OECD-countries and 27% in the whole world. Several sources estimate a continuing growth during the next 20 years in spite of an increasing use of natural gas and nuclear power. The reason is a strong

Spatio-temporal evolution of apparent resistivity during coal-seam hydraulic flushing

Science.gov (United States)

Li, Dexing; Wang, Enyuan; Song, Dazhao; Qiu, Liming; Kong, Xiangguo

2018-06-01

Hydraulic flushing in gas predrainage is widely used, but the hydraulic-flushing effect is evaluated in a traditional way, by determining the desorption volume, moisture content, gas drainage rate and other conventional indices. To verify the rationality and feasibility of the multielectrode resistivity method in the evaluation of coal-seam hydraulic flushing and to research the spatio-temporal evolution of apparent resistivity during hydraulic flushing, a field test was conducted in 17# coal seam at Nuodong Mine, Guizhou. During hydraulic flushing, four stages were defined according to the variation in coal rock resistivity with time, namely, the preparation stage, the sharply decreasing stage, the rapidly increasing stage and the steady stage. The apparent resistivity of the coal rock mass is affected mainly by its own degree of fragmentation and flushing volume. A more serious rupture and a greater flushing volume yield a smaller apparent resistivity during the sharply decreasing stage and a higher resistivity during the stable stage. After three months of gas predrainage, the residual gas content and the gas pressure at different points in the expected affected area decrease below the critical value. Changes in the residual gas content and gas pressure at these points are consistent with the apparent resistivity, which validates the rationality and feasibility of the multielectrode resistivity method in evaluating coal-seam hydraulic flushing.

NO{sub x} controls for coal-fired utility boilers in East Central Europe

Energy Technology Data Exchange (ETDEWEB)

Eskinazi, D. [Electric Power Research Inst., Washington, DC (United States); Tavoulareas, E.S. [Energy Technologies Enterprises Corp., McLean, VA (United States)

1995-12-01

Increasing environmental pressures worldwide, including East Central Europe are placing greater emphasis on NO{sub x} emission controls in utility power plants. Western Europe, Japan and the U.S. have significant experience in applying NO{sub x} controls, especially in boilers firing hard coal. Some countries in Europe (i.e., Germany and Austria), have gained experience in applying NO{sub x} controls in boilers firing low-rank coal. This experience can be applied to East Central European countries in providing the basis for planning NO{sub x} control projects, suggesting cost-effective solutions, and providing lessons learned. However, while the experience is generally applicable to East Central European countries, differences in boiler design, operation and coal characteristics also need to be considered. This paper begins with a comparison of the NO{sub x} regulations, identifies the key NO{sub x} control technologies and the worldwide experience with them, and discusses the achievable NO{sub x} reduction, O&M impacts, and retrofit costs for each technology. Emphasis is placed on retrofit applications for existing boilers, because new coal-fired power plants are not expected to be built for the next 5-10 years. This paper also focuses on technologies with relatively low cost and operational simplicity: combustion system tuning/optimization. low-NO{sub x} burners (LNB), overfire air (OFA), selective non-catalytic reduction (SNCR), and reburning.

Analyses of the performance of the ASTRID-like TRU burners in regional scenario studies - 5136

International Nuclear Information System (INIS)

Vezzoni, B.; Gabrielli, F.; Rineiski, A.

2015-01-01

In the past, large Sodium Fast Reactors systems (earlier CAPRA/CADRA, later ESFR and ESFR-like systems) and Accelerator Driven Systems (ADS-EFIT) were considered and extensively studied in Europe for managing MAs/Pu within regional or national scenario studies. After the ASTRID system was proposed in France, ASTRID-like burners could be considered as further options to be investigated. Low conversion ratio (CR) ASTRID-like burner cores (1200 MWth) have been considered at KIT by introducing few modifications with respect to the original French ASTRID design. These modifications allow keeping almost unchanged the main characteristics of the system (e.g. thermal power) and avoiding a strong deterioration of safety parameters (such as sodium void effect) after introduction of large amounts of Pu (more than 20%) and MAs (2-12%) in the fuel. These cores have already been studied at KIT for phase-out scenarios. A constant energy production case, relevant for a European or another regional scenario is considered in the paper. Cases with different shares (from 10 to 30%) of ASTRID-like burners in the nuclear energy fleet are compared. The results show that the ASTRID-like burners allow the use of all TRUs compositions foreseen in the fuel cycle with a proper choice of the MAs to Pu ratios and of the U/TRUs fractions either in phasing-out and on-going nuclear energy utilization conditions. The results show that a mixed fleet composed of 11% burners and 89% ESFR is able to stabilize the MAs in the cycle. The same stabilization is obtained with a fleet composed by 33% burner in combination with LWRs only

Late Cretaceous coal overlying karstic bauxite deposits in the Parnassus-Ghiona Unit, Central Greece: Coal characteristics and depositional environment

Energy Technology Data Exchange (ETDEWEB)

Kalaitzidis, Stavros; Siavalas, George; Christanis, Kimon [Dept. of Geology, University of Patras, 26504 Rio-Patras (Greece); Skarpelis, Nikos [Dept. of Geology and Geoenvironment, University of Athens, 15784 Zografou (Greece); Araujo, Carla Viviane [Petrobras-Cenpes GEOQ/PDEXP, Rua Horacio Macedo n 950, Cidade Universitaria - Ilha do Fundao, 21941-915 Rio de Janeiro (Brazil)

2010-04-01

The Pera-Lakkos coal located on top of bauxite deposits in the Ghiona mining district (Central Greece), is the only known Mesozoic (Late Cretaceous) coal in the country. It was derived from herbaceous plants and algae growing in mildly brackish mires that formed behind a barrier system during a regression of the sea, on a karstified limestone partly filled in with bauxitic detritus. Petrological, mineralogical and geochemical data point to the predominance of reducing conditions and intense organic matter degradation in the palaeomires. O/C vs. H/C and OI vs. HI plots, based on elemental analysis and Rock-Eval data, characterize kerogen types I/II. This reflects the relatively high liptinite content of the coal. Besides kerogen composition, O/C vs. H/C plot for the Pera-Lakkos coals is in accordance with a catagenesis stage of maturation in contrast with vitrinite reflectance and T{sub max} from Rock-Eval pyrolysis, which indicate the onset of oil window maturation stage. Suppression of vitrinite reflectance should be considered and the high liptinite content corroborates this hypothesis. Despite some favourable aspects for petroleum generation presented by the Pera-Lakkos coal, its maximum thickness (up to 50 cm) points to a restricted potential for petroleum generation. Coal oxidation took place either during the late stage of peat formation, due to wave action accompanying the subsequent marine transgression, or epigenetically after the emergence of the whole sequence due to percolation of drainage waters. Both options are also supported by the REE shale-normalized profiles, which demonstrate an upwards depletion in the coal layer. Oxidation also affected pyrite included in the coal; this led to the formation of acidic (sulfate-rich) solutions, which percolated downwards resulting in bleaching of the upper part of the underlying bauxite. (author)

Mitsubishi latest coal fired USC boiler technology (CFE Pacifico 700 MW)

Energy Technology Data Exchange (ETDEWEB)

Hashimoto, T.; Sakamoto, K. [Mitsubishi Heavy Industries, Ltd., Nagasaki (Japan). Power Systems; Fujitab, M. [Mitsubishi Heavy Industries, Ltd., Yokohama (Japan). Power Systems

2013-07-01

Mitsubishi Heavy Industries, Ltd. (MHI) has successfully completed commissioning work for CFE (Comision Federal de Electricidad) Pacifico 700 MW coal-fired unit in March 2010 which is the first supercritical unit in Latin America. This supercritical boiler was designed with state of the art technologies such as low NOx burners, high fineness pulverizers, advanced vertical furnace wall technology and so on. Especially the advanced vertical furnace wall technology with some improvements is a key technology to realize swift load changes such as 5% load per minute ramping rate with assuring dynamic characteristics. Recently the requirement of the high efficiency and the swift load changes for the power boilers has been increased so that even a coal-fired unit needs flexible operation characteristics for balancing variety of power sources. One of the challenges for the swift load change is to keep the furnace wall metal temperature low during the load change, which the advanced vertical furnace wall could realize. The report describes the features of the unit and commissioning result including load swing test results in details.

The effect of heat transfer on acoustics in burner stabilized flat flames

OpenAIRE

Schreel, K.R.A.M.; Tillaart, van den, E.L.; Janssen, R.W.M.; Goey, de, L.P.H.; Vovelle, C.; Lucka, K.

2003-01-01

Modern central heating systems use low NO$_x$ premixed burners with a large modulation range. This can lead to noise problems which cannot be solved via trial and error, but need accurate modelling. An acoustic analysis as part of the design phase can reduce the time-to-market considerably, but the acoustic response of the flame is an unknown and complex key-factor. In this study, the influence of the heat transfer between the gas and the burner on the acoustic transfer coefficient is studied...

Polonium release from an ATW burner system with liquid lead-bismuth coolant

International Nuclear Information System (INIS)

Li, N.; Yefimov, E.; Pankratov, D.

1998-04-01

The authors analyzed polonium release hazards in a conceptual pool-type ATW burner with liquid lead-bismuth eutectic (LBE) coolant. Simplified quantitative models are used based on experiments and real NPP experience. They found little Po contamination outside the burner under normal operating conditions with nominal leakage from the gas system. In sudden gas leak and/or coolant spill accidents, the P contamination level can reach above the regulation limit but short exposure would not lead to severe health consequences. They are evaluating and developing mitigation methods

40 CFR 266.102 - Permit standards for burners.

Science.gov (United States)

2010-07-01

... or industrial furnace downstream of the combustion zone and prior to release of stack gases to the... MANAGEMENT FACILITIES Hazardous Waste Burned in Boilers and Industrial Furnaces § 266.102 Permit standards for burners. (a) Applicability—(1) General. Owners and operators of boilers and industrial furnaces...

Staged combustion - main method for suppressing nitrogen oxides in pulverized-coal fired boilers

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R. (Vsesoyuznyi Teplotekhnicheskii Institut (USSR))

1989-08-01

Describes principles behind staged combustion, which is based on organizing furnace operations so that only part of the air from the fuel is taken into the furnace. The remaining air, which is needed for combustion, is fed as a tertiary blast jet into the intermediate flame zone. Following inflammation and combustion of the volatile matter, the oxygen concentration in the flame drops sharply causing a retardation of the oxidation reactions forming NO and an intensification of the reactions causing the nitrogen-containing radicals NH{sub i} and CN to be converted into N{sub 2}. When the reducing agents CO, H{sub 2} and CH{sub 4} are present in certain flame zones, even the nitrogen oxide is reduced to N{sub 2}. The NO concentrations in the flame are reduced until the jet of tertiary air is introduced. Discusses with reference to practice in the USA and Western Europe how to achieve maximum effect of this method for different types of boiler and presents the results of observations of the introduction of staged combustion to the BKZ-210-140 boiler burning Kuznetsk gassy coal. 5 refs.

Burner Rig Hot Corrosion of a Single Crystal Ni-48Al-Ti-Hf-Ga Alloy

Science.gov (United States)

Nesbitt, James A.; Darolia, Ram; Cuy, Michael D.

1998-01-01

The hot corrosion resistance of a single crystal Ni-48Al-1Ti-0.5Hf-0.2Ga alloy was examined in a Mach 0.3 burner rig at 900 C for 300 hours. The combustion chamber was doped with 2 ppmw synthetic sea salt. The hot corrosion attack produced a random mound morphology on the surface. Microstructurally, the hot corrosion attack appeared to initiate with oxide-filled pits which were often broad and shallow. At an intermediate stage, the pits increased in size to incorporate unoxidized Ni islands in the corrosion product. The rampant attack stage, which was observed only at sharp sample corners, was characterized by rapid inward growth of alumina in finger-like protrusions incorporating significant amounts of Al-depleted Ni islands. Aluminum consumption in the oxide fingers resulted in the growth of a gamma' layer ahead of the advancing oxide fingers.

Burner rig hot corrosion of a single crystal Ni-48Al-Ti-Hf-Ga alloy

Energy Technology Data Exchange (ETDEWEB)

Nesbitt, J.A.; Darolia, R.; Cuy, M.D.

1999-07-01

The hot corrosion resistance of a single crystal Ni-48Al-1Ti-0.5Hf-0.2Ga alloy was examined in a Mach 0.3 burner rig at 900 C for 300 hours. The combustion chamber was doped with 2 ppmw synthetic sea salt. The hot corrosion attack produced a random mound morphology on the surface. Microstructurally, the hot corrosion attack appeared to initiate with oxide-filled pits which were often broad and shallow. At an intermediate stage, the pits increased in size to incorporate unoxidized Ni islands in the corrosion product. The rampant attack stage, which was observed only at sharp sample corners, was characterized by rapid inward growth of alumina in finger-like protrusions incorporating significant amounts of Al-depleted Ni islands. Aluminum consumption in the oxide fingers resulted in the growth of a {gamma}{prime} layer ahead of the advancing oxide fingers.

EXPLORATORY RESEARCH ON NOVEL COAL LIQUEFACTION CONCEPT

Energy Technology Data Exchange (ETDEWEB)

Brandes, S.D.; Winschel, R.A.

1998-11-30

The report presents a summary the work performed under DOE Contract No. DE-AC22-95PC95050. Investigations performed under Task 4--Integrated Flow Sheet Testing are detailed. In this program, a novel direct coal liquefaction technology was investigated by CONSOL Inc. with the University of Kentucky Center for Applied Energy Research and LDP Associates. The process concept explored consists of a first-stage coal dissolution step in which the coal is solubilized by hydride ion donation. In the second stage, the products are catalytically upgraded to refinery feedstocks. Integrated first-stage and solids-separation steps were used to prepare feedstocks for second-stage catalytic upgrading. An engineering and economic evaluation was conducted concurrently with experimental work throughout the program. Approaches to reduce costs for a conceptual commercial plant were recommended at the conclusion of Task 3. These approaches were investigated in Task 4. The economic analysis of the process as it was defined at the conclusion of Task 4, indicates that the production of refined product (gasoline) via this novel direct liquefaction technology is higher than the cost associated with conventional two-stage liquefaction technologies.

Coal fights back

International Nuclear Information System (INIS)

Ince, R.

1990-01-01

During the twentieth century coal has moved from being the dominant energy hero that fueled the industrial revolution to a background role: a fuel of last choice, a supplemental resource, and sometimes a convenient villain in the environmental debate. But, as this paper points out, the other side of the coin is that coal is dependable, plentiful, and the price is right. To examine the issue as it merits, reason will have to be substituted for emotion. We are currently in what the author of this paper calls the crisis enrichment stage of the debate. In this stage, when definitive knowledge is lacking, there is a temptation to imagine the worst, overcorrect the problem, and do considerable damage to energy supply and economic needs. The environmental movement has provoked a hunt for someone to blame for the world's current environmental situation. Without a proven culprit to blame for disturbances to some of the world's lakes and forests, it has been decided that coal is the cause. This paper makes a plea for balance, urging all parties to find some acceptable middle ground between energy production and environmental protection

Improving combustion characteristics and NO(x) emissions of a down-fired 350 MW(e) utility boiler with multiple injection and multiple staging.

Science.gov (United States)

Kuang, Min; Li, Zhengqi; Xu, Shantian; Zhu, Qunyi

2011-04-15

Within a Mitsui Babcock Energy Limited down-fired pulverized-coal 350 MW(e) utility boiler, in situ experiments were performed, with measurements taken of gas temperatures in the burner and near the right-wall regions, and of gas concentrations (O(2) and NO) from the near-wall region. Large combustion differences between zones near the front and rear walls and particularly high NO(x) emissions were found in the boiler. With focus on minimizing these problems, a new technology based on multiple-injection and multiple-staging has been developed. Combustion improvements and NO(x) reductions were validated by investigating three aspects. First, numerical simulations of the pulverized-coal combustion process and NO(x) emissions were compared in both the original and new technologies. Good agreement was found between simulations and in situ measurements with the original technology. Second, with the new technology, gas temperature and concentration distributions were found to be symmetric near the front and rear walls. A relatively low-temperature and high-oxygen-concentration zone formed in the near-wall region that helps mitigate slagging in the lower furnace. Third, NO(x) emissions were found to have decreased by as much as 50%, yielding a slight decrease in the levels of unburnt carbon in the fly ash.

Thermal-hydraulics of actinide burner reactors

International Nuclear Information System (INIS)

Takizuka, Takakazu; Mukaiyama, Takehiko; Takano, Hideki; Ogawa, Toru; Osakabe, Masahiro.

1989-07-01

As a part of conceptual study of actinide burner reactors, core thermal-hydraulic analyses were conducted for two types of reactor concepts, namely (1) sodium-cooled actinide alloy fuel reactor, and (2) helium-cooled particle-bed reactor, to examine the feasibility of high power-density cores for efficient transmutation of actinides within the maximum allowable temperature limits of fuel and cladding. In addition, calculations were made on cooling of actinide fuel assembly. (author)

Fully automatic and self-learning process optimisation to increase efficiency of large-scale power plants by correlation of data from the process control system with optical and acoustic information; Vollautomatische und selbstlernende Prozessoptimierung zur Wirkungsgradsteigerung von Grosskraftwerken. Softwaregestuetzte Korrelation der Prozessdaten mit optischen und akustischen Informationen

Energy Technology Data Exchange (ETDEWEB)

Hanf, Alexander Carl [Powitec Intelligent Technologies GmbH, Essen (Germany)

2009-07-01

Economic necessities have led to new challenges for the operation of coal steam generators in large power plants. The strongly fluctuating quality, in particular of imported coal, design and coal-dependent uneven distribution of pulverised coal results in a sub-optimal combustion air distribution if classical control concepts are used. This has a direct negative impact on efficiency. By using a system package consisting of intelligent software and optical sensors for flame analysis and acoustic sensors for milling degree analysis, the fuel-/air-ratio for each burner and over the burner levels is optimised. (orig.)

Studies on the catalysts for coal liquefaction. ; Rheological studies of coal liquefaction process. Sekitan ekikayo shokubai ni kansuru kenkyu. ; Sekitan ekika process no rheology teki kenkyu

Energy Technology Data Exchange (ETDEWEB)

Muraoka, T; Oda, H; Yokokawa, C [Kansai University, Osaka (Japan). Faculty of Engineering

1991-11-07

Hydrogenolysis of different rank coals as Taiheiyo coal (75.7C%) and Pittston coal (85.4C%) were conducted in the presence of four kinds of catalysts (CuCrO4, Fe2O3+S, MoO3-TiO2 and MoS3-Al2O3) with an addition of tetralin as vehicle. The variation in viscosity in every reaction system was traced in the initial stage of the reaction by a torque meter attached to an autoclave. As a result, in every system, the torque decreased in the initial stage of temperature rise because of reduction of a solvent viscosity. The torque subsequently increased with temperature indicating two peaks before the following gradual decrease. In Taiheiyo coal, both peaks were low, and its coal conversion was more than 85%, while in Pittston coal, both peaks were sharp and high, and both subsequent torque reduction and coal conversion were smaller than those of Taiheiyo coal. 5 refs., 10 figs., 2 tabs.

Effect of combustion characteristics on wall radiative heat flux in a 100 MWe oxy-coal combustion plant

Energy Technology Data Exchange (ETDEWEB)

Park, S.; Ryu, C. [Sungkyunkwan Univ., Suwon (Korea, Republic of). School of Mechanical Engineering; Chae, T.Y. [Sungkyunkwan Univ., Suwon (Korea, Republic of). School of Mechanical Engineering; Korea Institute of Industrial Technology, Cheonan (Korea, Republic of). Energy System R and D Group; Yang, W. [Korea Institute of Industrial Technology, Cheonan (Korea, Republic of). Energy System R and D Group; Kim, Y.; Lee, S.; Seo, S. [Korea Electric Power Research Institute (KEPRI), Daejeon (Korea, Republic of). Power Generation Lab.

2013-07-01

Oxy-coal combustion exhibits different reaction, flow and heat transfer characteristics from air-coal combustion due to different properties of oxidizer and flue gas composition. This study investigated the wall radiative heat flux (WRHF) of air- and oxy-coal combustion in a simple hexahedral furnace and in a 100 MWe single-wall-fired boiler using computational modeling. The hexahedral furnace had similar operation conditions with the boiler, but the coal combustion was ignored by prescribing the gas properties after complete combustion at the inlet. The concentrations of O{sub 2} in the oxidizers ranging between 26 and 30% and different flue gas recirculation (FGR) methods were considered in the furnace. In the hexahedral furnace, the oxy-coal case with 28% of O{sub 2} and wet FGR had a similar value of T{sub af} with the air-coal combustion case, but its WRHF was 12% higher. The mixed FGR case with about 27% O{sub 2} in the oxidizer exhibited the WRHF similar to the air-coal case. During the actual combustion in the 100 MWe boiler using mixed FGR, the reduced volumetric flow rates in the oxy-coal cases lowered the swirl strength of the burners. This stretched the flames and moved the high temperature region farther to the downstream. Due to this reason, the case with 30% O{sub 2} in the oxidizers achieved a WRHF close to that of air-coal combustion, although its adiabatic flame temperature (T{sub af}) and WHRF predicted in the simplified hexahedral furnace was 103 K and 10% higher, respectively. Therefore, the combustion characteristics and temperature distribution significantly influences the WRHF, which should be assessed to determine the ideal operating conditions of oxy- coal combustion. The choice of the weighted sum of gray gases model (WSGGM) was not critical in the large coal-fired boiler.

CFD simulation of a burner for syngas characterization and experimental validation

Energy Technology Data Exchange (ETDEWEB)

Fantozzi, Francesco; Desideri, Umberto [University of Perugia (Italy). Dept. of Industrial Engineering], Emails: fanto@unipg.it, umberto.desideri@unipg.it; D' Amico, Michele [University of Perugia (Italy). Dept. of Energetic Engineering], E-mail: damico@crbnet.it

2009-07-01

Biomass and waste are distributed and renewable energy sources that may contribute effectively to sustainability if used on a small and micro scale. This requires the transformation through efficient technologies (gasification, pyrolysis and anaerobic digestion) into a suitable gaseous fuel to use in small internal combustion engines and gas turbines. The characterization of biomass derived syngas during combustion is therefore a key issue to improve the performance of small scale integrated plants because synthesis gas show significant differences with respect to Natural Gas (mixture of gases, low calorific value, hydrogen content, tar and particulate content) that may turn into ignition problems, combustion instabilities, difficulties in emission control and fouling. To this aim a burner for syngas combustion and LHV measurement through mass and energy balance was realized and connected to the rotary-kiln laboratory scale pyrolyzer at the Department of Industrial Engineering of the University of Perugia. A computational fluid dynamics (CFD) simulation of the burner was carried out considering the combustion of propane to investigate temperature and pressure distribution, heat transmission and distribution of the combustion products and by products. The simulation was carried out using the CFD program Star-CD. Before the simulation a geometrical model of the burner was built and the volume of model was subdivided in cells. A sensibility analysis of cells was carried out to estimate the approximation degree of the model. Experimental data about combustion emission were carried out with the propane combustion in the burner, the comparison between numerical results and experimental data was studied to validate the simulation for future works involved with the combustion of treated or raw (syngas with tar) syngas obtained from pyrolysis process. (author)

Low Emissions Burner Technology for Metal Processing Industry using Byproducts and Biomass Derived Liquid Fuels

Energy Technology Data Exchange (ETDEWEB)

Agrawal, Ajay; Taylor, Robert

2013-09-30

This research and development efforts produced low-emission burner technology capable of operating on natural gas as well as crude glycerin and/or fatty acids generated in biodiesel plants. The research was conducted in three stages (1) Concept definition leading to the design and development of a small laboratory scale burner, (2) Scale-up to prototype burner design and development, and (3) Technology demonstration with field vefiication. The burner design relies upon the Flow Blurring (FB) fuel injection based on aerodynamically creating two-phase flow near the injector exit. The fuel tube and discharge orifice both of inside diameter D are separated by gap H. For H < 0.25D, the atomizing air bubbles into liquid fuel to create a two-phase flow near the tip of the fuel tube. Pressurized two-phase fuel-air mixture exits through the discharge orifice, which results in expansion and breakup of air bubbles yielding a spray with fine droplets. First, low-emission combustion of diesel, biodiesel and straight VO (soybean oil) was achieved by utilizing FB injector to yield fine sprays for these fuels with significantly different physical properties. Visual images for these baseline experiments conducted with heat release rate (HRR) of about 8 kW illustrate clean blue flames indicating premixed combustion for all three fuels. Radial profiles of the product gas temperature at the combustor exit overlap each other signifying that the combustion efficiency is independent of the fuel. At the combustor exit, the NOx emissions are within the measurement uncertainties, while CO emissions are slightly higher for straight VO as compared to diesel and biodiesel. Considering the large variations in physical and chemical properties of fuels considered, the small differences observed in CO and NOx emissions show promise for fuel-flexible, clean combustion systems. FB injector has proven to be very effective in atomizing fuels with very different physical properties, and it offers a

The use of mechanically activated micronized coal in thermal power engineering

Directory of Open Access Journals (Sweden)

Burdukov Anatoliy P.

2016-01-01

Full Text Available Coal is one of the main energy resources and development of new promising technologies on its basis is certainly topical. This article discusses the use of new technology of gas and fuel oil replacement by mechanically activated micronized coal in power engineering: ignition and stabilization of pulverized coal flame combustion, as well as gasification of micronized coal in the flow. The new technology coal combustion with two stages of grinding is suggested. Optimization of the scheme of two-stage combustion is calculated. The first experimental data on the combustion process are obtained. The first demonstration tests on gas and heavy oil replacement by micronized coal during boiler ignition were carried out in the real power boiler with the capacity of 320 tons of steam per hour.

British coal-down to the line

International Nuclear Information System (INIS)

Anon.

1993-01-01

The long-running saga of British Coal's decline is in its final stages with virtually no change from last October when the British government announced plants to close 31 of the 50 remaining mines. That announcement produced a political outcry but having privatized the electricity industry in 1990 the government had effectively left itself up the creek without a paddle. It had no powers to force the generators to buy more coal. The status of the British coal industry is discussed

PULSE DRYING EXPERIMENT AND BURNER CONSTRUCTION

Energy Technology Data Exchange (ETDEWEB)

Robert States

2006-07-15

Non steady impingement heat transfer is measured. Impingement heating consumes 130 T-BTU/Yr in paper drying, but is only 25% thermally efficient. Pulse impingement is experimentally shown to enhance heat transfer by 2.8, and may deliver thermal efficiencies near 85%. Experimental results uncovered heat transfer deviations from steady theory and from previous investigators, indicating the need for further study and a better theoretical framework. The pulse burner is described, and its roll in pulse impingement is analyzed.

Early detection of spontaneous combustion of coal in underground coal mines with development of an ethylene enriching system

Energy Technology Data Exchange (ETDEWEB)

Xie, Jun; Xue, Sheng [CSIRO Earth Science and Resource Engineering, Kenmore (Australia); Cheng, Weimin; Wang, Gang [Shandong University of Science and Technology, Qingdao (China)

2011-01-01

Spontaneous combustion of coal (sponcom) is a major hazard in underground coal mining operations. If not detected early and managed properly, it can seriously affect mine safety and productivity. Gaseous products of sponcom, such as carbon monoxide, ethylene and hydrogen, are commonly used in coal mines as indicators to reflect the state of the sponcom. Studies have shown that ethylene starts to occur when sponcom reaches a characteristic temperature. However, due to dilution of ventilation air and detection limits of the instruments used for gas analysis at coal mines, ethylene cannot be detected until the sponcom has developed past its early stage, missing an optimum opportunity for mine operators to control the hazard. To address the issue, an ethylene-enriching system, based on its physical adsorption and desorption properties, has been developed to increase detection sensitivity of the ethylene concentration in mine air by about 10 times. This system has successfully been applied in a number of underground coal mines in China to detect sponcom at its early stage and enable mine operators to take effective control measures. This paper describes the ethylene enriching system and its application. (author)

Thermal behavior and kinetics of bio-ferment residue/coal blends during co-pyrolysis

International Nuclear Information System (INIS)

Du, Yuying; Jiang, Xuguang; Lv, Guojun; Ma, Xiaojun; Jin, Yuqi; Wang, Fei; Chi, Yong; Yan, Jianhua

2014-01-01

Highlights: • The Activation energy for the blends is lower than that of BR and coal when BR < 50%. • The BR/coal blends start to decompose at approximately 45 °C releasing ammonia. • The yield of gaseous products increases with increasing BR blending ratio. • NH 3 , alkanes and CO 2 increase with increasing BR blending ratio. • Interactions most likely occur between the BR and the coal during co-pyrolysis. - Abstract: In this work, the thermal behavior and kinetics of bio-ferment residue (BR) and coal blends during co-pyrolysis were investigated using TG-FTIR and kinetic analysis. The co-pyrolysis of BR and coal occurred in three major stages. The BR/coal blends lost most of their weight during the devolatilization stage. The kinetics of the BR/coal blends in this stage implied that the activation energy was lower than that of BR and coal below a certain BR blending ratio. The BR/coal blends started to decompose at approximately 45 °C, releasing ammonia followed by alkanes, carbon dioxide, methane and carbon monoxide. The total yield of gaseous products (primarily ammonia, alkanes and carbon dioxide) increased with increasing BR blending ratio. Moreover, interactions most likely occurred between the BR and the coal during co-pyrolysis

Characterization of a Rijke Burner as a Tool for Studying Distribute Aluminum Combustion

OpenAIRE

Newbold, Brian R.

1996-01-01

As prelude to the quantitative study of aluminum distributed combustion, the current work has characterized the acoustic growth, frequency, and temperature of a Rijke burner as a function of mass flow rate, gas composition, and geometry. By varying the exhaust temperature profile, the acoustic growth rate can be as much as tripled from the baseline value of approximately 120 s-1• At baseline, the burner operated in the third harmonic mode at a frequency of 1300 Hz, but geometry or temperature...

Reduction in nitrogen oxide emissions by boiler construction companies in the USA

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R.

1989-11-01

Explains that in the USA greater emphasis is placed on reducing pollutant emissions by altering the combustion process than by cleaning flue gases. Results of a joint USA/FRG program show that NO{sub x} concentrations may vary greatly according to the type of slag removal (solid or liquid) and the location and type of burners used. Examines variants and demonstrates that the most effective method of reducing NO{sub x} emissions from large-scale pulverized-coal fired boilers is three-stage combustion used in conjunction with a flue gas cleaning method such as selective catalytic reduction (cyclone burners). Trials found that this method results in a 60% drop in NO{sub x} emissions and, if limestone is added to the tertiary air, a 20% drop in SO{sub 2}. Best results from an economic aspect were achieved when gas was burned in the extra burners. 6 refs.

Experimental Evaluation of a Low Emissions High Performance Duct Burner for Variable Cycle Engines (VCE)

Science.gov (United States)

Lohmann, R. P.; Mador, R. J.

1979-01-01

An evaluation was conducted with a three stage Vorbix duct burner to determine the performance and emissions characteristics of the concept and to refine the configuration to provide acceptable durability and operational characteristics for its use in the variable cycle engine (VCE) testbed program. The tests were conducted at representative takeoff, transonic climb, and supersonic cruise inlet conditions for the VSCE-502B study engine. The test stand, the emissions sampling and analysis equipment, and the supporting flow visualization rigs are described. The performance parameters including the fuel-air ratio, the combustion efficiency/exit temperature, thrust efficiency, and gaseous emissions calculations are defined. The test procedures are reviewed and the results are discussed.

Combustion Characteristics of Butane Porous Burner for Thermoelectric Power Generation

Directory of Open Access Journals (Sweden)

K. F. Mustafa

2015-01-01

Full Text Available The present study explores the utilization of a porous burner for thermoelectric power generation. The porous burner was tested with butane gas using two sets of configurations: single layer porcelain and a stacked-up double layer alumina and porcelain. Six PbSnTe thermoelectric (TE modules with a total area of 54 cm2 were attached to the wall of the burner. Fins were also added to the cold side of the TE modules. Fuel-air equivalence ratio was varied between the blowoff and flashback limit and the corresponding temperature, current-voltage, and emissions were recorded. The stacked-up double layer negatively affected the combustion efficiency at an equivalence ratio of 0.20 to 0.42, but single layer porcelain shows diminishing trend in the equivalence ratio of 0.60 to 0.90. The surface temperature of a stacked-up porous media is considerably higher than the single layer. Carbon monoxide emission is independent for both porous media configurations, but moderate reduction was recorded for single layer porcelain at lean fuel-air equivalence ratio. Nitrogen oxides is insensitive in the lean fuel-air equivalence ratio for both configurations, even though slight reduction was observed in the rich region for single layer porcelain. Power output was found to be highly dependent on the temperature gradient.

Using coal mine saline water to produce chlorine

Energy Technology Data Exchange (ETDEWEB)

Gnot, W; Turek, M; Walburg, Z

1979-01-01

Utilizing hard coal mine waters with salt concentration reaching 140 kg/mat3 in the chemical industry would significantly reduce the cost of protecting the natural environment from salt. The Institute of Chemistry and Inorganic Technology of the Silesian Technical University in Gliwice developed an efficient technology of producing chorine from underground black coal mine waters. A scheme of the technology is explained: double stage brine purification with magnesium hydroxide as by-product. During the first stage magnesium is precipitated using sodium hydroxide; after increasing salt content in the brine calcium and a low percentage of magnesium are removed by lye-sodium method. During the second stage sedimentation rate increases to 1.4 mm/s, and volume of sludge is only 1%. Magnesium hydroxide is removed using a method patented in Poland (after adding a flocculant magnesium hydroxide is left untouched). Only at a later stage does sedimentation occur. The proposed technology of utilizing mine water will be tested in an experimental plant which will be built at the Ziemowit black coal mine. (7 refs.) (In Polish)

Design process and instrumentation of a low NOx wire-mesh duct burner for micro-cogeneration unit

Energy Technology Data Exchange (ETDEWEB)

Ramadan, O.B.; Gauthier, J.E.D. [Carleton Univ., Ottawa, ON (Canada). Dept. of Mechanical and Aerospace Engineering; Hughes, P.M.; Brandon, R. [Natural Resources Canada, Ottawa, ON (Canada). CANMET Energy Technology Centre

2007-07-01

Air pollution and global climate change have become a serious environmental problem leading to increasingly stringent government regulations worldwide. New designs and methods for improving combustion systems to minimize the production of toxic emissions, like nitrogen oxides (NOx) are therefore needed. In order to control smog, acid rain, ozone depletion, and greenhouse-effect warming, a reduction of nitrogen oxide is necessary. One alternative for combined electrical power and heat generation (CHP) are micro-cogeneration units which use a micro-turbine as a prime mover. However, to increase the efficiencies of these units, micro-cogeneration technology still needs to be developed further. This paper described the design process, building, and testing of a new low NOx wire-mesh duct burner (WMDB) for the development of a more efficient micro-cogeneration unit. The primary goal of the study was to develop a practical and simple WMDB, which produces low emissions by using lean-premixed surface combustion concept and its objectives were separated into four phases which were described in this paper. Phase I involved the design and construction of the burner. Phase II involved a qualitative flow visualization study for the duct burner premixer to assist the new design of the burner by introducing an efficient premixer that could be used in this new application. Phase III of this research program involved non-reacting flow modeling on the burner premixer flow field using a commercial computational fluid dynamic model. In phase IV, the reacting flow experimental investigation was performed. It was concluded that the burner successfully increased the quantity and the quality of the heat released from the micro-CHP unit and carbon monoxide emissions of less than 9 ppm were reached. 3 refs., 3 figs.

Emission characteristics and axial flame temperature distribution of producer gas fired premixed burner

Energy Technology Data Exchange (ETDEWEB)

Bhoi, P.R. [Department of Mechanical Engineering, L and T-Sargent and Lundy Limited, L and T Energy Centre, Near Chhani Jakat Naka, Baroda 390 002 (India); Channiwala, S.A. [Department of Mechanical Engineering, Sardar Vallabhbhai National Institute of Technology, Deemed University, Ichchhanath, Surat 395 007, Gujarat (India)

2009-03-15

This paper presents the emission characteristics and axial flame temperature distribution of producer gas fired premixed burner. The producer gas fired premixed burner of 150 kW capacity was tested on open core throat less down draft gasifier system in the present study. A stable and uniform flame was observed with this burner. An instrumented test set up was developed to evaluate the performance of the burner. The conventional bluff body having blockage ratio of 0.65 was used for flame stabilization. With respect to maximum flame temperature, minimum pressure drop and minimum emissions, a swirl angle of 60 seems to be optimal. The experimental results also showed that the NO{sub x} emissions are inversely proportional to swirl angle and CO emissions are independent of swirl angle. The minimum emission levels of CO and NO{sub x} are observed to be 0.167% and 384 ppm respectively at the swirl angle of 45-60 . The experimental results showed that the maximum axial flame temperature distribution was achieved at A/F ratio of 1.0. The adiabatic flame temperature of 1653 C was calculated theoretically at A/F ratio of 1.0. Experimental results are in tune with theoretical results. It was also concluded that the CO and UHC emissions decreases with increasing A/F ratio while NO{sub x} emissions decreases on either side of A/F ratio of 1.0. (author)

Coal gasification. Quarterly report, April--June 1977

Energy Technology Data Exchange (ETDEWEB)

None

1978-01-01

The conversion of coal to high-Btu gas requires a chemical and physical transformation of solid coal. However, because coal has widely differing chemical and physical properties, depending on where it is mined, it is difficult to process. Therefore, to develop the most suitable techniques for gasifying coal, ERDA, together with the American Gas Association, is sponsoring the development of several advanced conversion processes. Although the basic coal-gasification chemical reactions are the same for each process, the processes under development have unique characteristics. A number of the processes for converting coal to high Btu and to low Btu gas have reached the pilot plant stage. The responsibility for designing, constructing and operating each of these pilot plants is defined and progress on each during the quarter is described briefly. The accumulation of data for a coal gasification manual and the development of mathematical models of coal gasification processes are reported briefly. (LTN)

Clean Coal Diesel Demonstration Project

Energy Technology Data Exchange (ETDEWEB)

Robert Wilson

2006-10-31

A Clean Coal Diesel project was undertaken to demonstrate a new Clean Coal Technology that offers technical, economic and environmental advantages over conventional power generating methods. This innovative technology (developed to the prototype stage in an earlier DOE project completed in 1992) enables utilization of pre-processed clean coal fuel in large-bore, medium-speed, diesel engines. The diesel engines are conventional modern engines in many respects, except they are specially fitted with hardened parts to be compatible with the traces of abrasive ash in the coal-slurry fuel. Industrial and Municipal power generating applications in the 10 to 100 megawatt size range are the target applications. There are hundreds of such reciprocating engine power-plants operating throughout the world today on natural gas and/or heavy fuel oil.

Thermionic cogeneration burner assessment study. Third quarterly technical progress report, April-June, 1983

Energy Technology Data Exchange (ETDEWEB)

1983-01-01

The specific tasks of this study are to mathematically model the thermionic cogeneration burner, experimentally confirm the projected energy flows in a thermal mock-up, make a cost estimate of the burner, including manufacturing, installation and maintenance, review industries in general and determine what groups of industries would be able to use the electrical power generated in the process, select one or more industries out of those for an in-depth study, including determination of the performance required for a thermionic cogeneration system to be competitive in that industry. Progress is reported. (WHK)

Refining and end use study of coal liquids

International Nuclear Information System (INIS)

1998-01-01

Two direct coal liquids were evaluated by linear programming analysis to determine their value as petroleum refinery feedstock. The first liquid, DL1, was produced from bitiuminous coal using the Hydrocarbon Technologies, Inc.(HTI) two-stage hydrogenation process in Proof of Concept Run No.1, POC-1. The second liquid, DL2,was produced from sub-bituminous coal using a three-stage HTI process in Proof of Concept Run No. 2, POC-2; the third stage being a severe hydrogenation process. A linear programming (LP) model was developed which simulates a generic 150,000 barrel per day refinery in the Midwest U.S. Data from upgrading tests conducted on the coal liquids and related petroleum fractions in the pilot plant testing phase of the Refining and End Use Study was inputed into the model. The coal liquids were compared against a generic petroleum crude feedstock. under two scenarios. In the first scenario, it was assumed that the refinery capacity and product slate/volumes were fixed. The coal liquids would be used to replace a portion of the generic crude. The LP results showed that the DL1 material had essentially the same value as the generic crude. Due to its higher quality, the DL2 material had a value of approximately 0.60 $/barrel higher than the petroleum crude. In the second scenario, it was assumed that a market opportunity exists to increase production by one-third. This requires a refinery expansion. The feedstock for this scenario could be either 100% petroleum crude or a combination of petroleum crude and the direct coal liquids. Linear programming analysis showed that the capital cost of the refinery expansion was significantly less when coal liquids are utilized. In addition, the pilot plant testing showed that both of the direct coal liquids demonstrated superior catalytic cracking and naphtha reforming yields. Depending on the coal liquid flow rate, the value of the DL1 material was 2.5-4.0 $/barrel greater than the base petroleum crude, while the DL2

Determination of the stagnation point in pulverized coal swirl flames by detailed analysis of laser velocity measurements; Staupunktbestimmung in Kohlenstaub-Drallflammen mittels detaillierter Analyse von LDA-Daten

Energy Technology Data Exchange (ETDEWEB)

Ohliger, A.; Stadler, H.; Foerster, M.; Kneer, R. [RWTH Aachen University (Germany). Lehrstuhl fuer Waerme- und Stoffuebertragung

2009-07-01

When Laser Doppler Anemometry (LDA) is used for experimental investigation of flow fields in pulverised coal flames, the measured coal particle velocities are usually averaged in order to determine the gas velocity. This paper shows that this approach can lead to a misinterpretation of the data. In the burner vicinity of the investigated flame, where high accelerations in the gas phase occur, a discrepancy appears between the measured velocity distribution and the expected normal distribution. Thus, a detailed analysis of the measured particle data is conducted and compared to conventional averaging. The difference can be attributed to large particles from the inner recirculation zone of the flame, which do not follow the gas flow properly. (orig.)

Fully Premixed Low Emission, High Pressure Multi-Fuel Burner

Science.gov (United States)

Nguyen, Quang-Viet (Inventor)

2012-01-01

A low-emissions high-pressure multi-fuel burner includes a fuel inlet, for receiving a fuel, an oxidizer inlet, for receiving an oxidizer gas, an injector plate, having a plurality of nozzles that are aligned with premix face of the injector plate, the plurality of nozzles in communication with the fuel and oxidizer inlets and each nozzle providing flow for one of the fuel and the oxidizer gas and an impingement-cooled face, parallel to the premix face of the injector plate and forming a micro-premix chamber between the impingement-cooled face and the in injector face. The fuel and the oxidizer gas are mixed in the micro-premix chamber through impingement-enhanced mixing of flows of the fuel and the oxidizer gas. The burner can be used for low-emissions fuel-lean fully-premixed, or fuel-rich fully-premixed hydrogen-air combustion, or for combustion with other gases such as methane or other hydrocarbons, or even liquid fuels.

Surface ignition behaviors of methane–air mixture in a gas oven burner

International Nuclear Information System (INIS)

Ryu, Jungwan; Kwon, Jongseo; Kim, Ryanggyun; Kim, Minseong; Kim, Youngsoo; Jeon, Chunghwan; Song, Juhun

2014-01-01

In a gas oven burner, commonly used as a residential appliance, a surface igniter is a critical component for creating a pilot flame near the surface that can propagate safely back to the nozzle of the burner. The igniter should meet critical operating requirements: a lower surface temperature needed to ignite a methane–air mixture and a stable/safe ignition sustained. Otherwise, such failure would result in an instantaneous peak in carbon monoxide emission and a safety hazard inside a closed oven. Several theoretical correlations have been used to predict ignition temperature as well as the critical ignition/extinction limit for a stagnation flow ignition. However, there have only been a few studies on ignition modes or relevant stability analysis, and therefore a more detailed examination of the transient ignition process is required. In this study, a high-speed flame visualization technique with temperature measurement was employed to reveal a surface ignition phenomenon and subsequent flame propagation of a cold combustible methane–air mixture in a gas oven burner. The operating parameters were the temperature–time history of the igniter surface, mixture velocity, and the distance of the igniter from the nozzle. The surface ignition temperatures were analyzed for such parameters under a safe ignition mode, while several abnormal modes leading to ignition failure were also recognized. - Highlights: •We revealed a surface ignition behavior of combustible mixture in gas oven burner. •We employed a flame visualization technique with temperature measurement. •We evaluated effects of parameters such as lifetime, mixture velocity and igniter distance. •We recognized several abnormal modes leading to ignition failure

The method of waste liquid atomization/incineration by using ultrasonic industrial burners

International Nuclear Information System (INIS)

Bartonek, Thomas

1999-01-01

The problem of burning a fuel is closely related to distributing that fuel and mixing it with the combustion air within a pre-designated space, the combustion chamber. For fuel engineers, the rule of thumb is unchanged: mix it and it will burn. That is why the burner designer focuses his attention on incorporating the best possible atomization and mixing, equipment, i.c. in the end, on the construction of the atomizer nozzle and the control of the combustion air. It was these considerations plus the inability of conventional burners to meet the tough demands of today's applications that led DUMAG to undertake an intensive program of research which has now been crowned with success. Below, basic points drawn from the fundamental knowledge of all fuel engineers have been included to bring into sharper focus the operating principles of the DUMAG Ultrasonic Industrial Burner, a world class Austrian product. This paper describes a plant which has been operating without incident since October 1977. Its level of operational effectiveness is at least equivalent to that of a standard oil burner plant. The plant is also in full compliance with current environmental standards following the installation of additional safety equipment such as pre-combustion chambers, sensors to monitor pre-combustion chamber temperatures, cut-off valves for reaction water and solvents to block their flow if no heating oil is being fed in, flue gas density monitor, and finer atomization and better mixing by means of an ultrasonic system - even with fluctuations in the viscosity. By eliminating disposal costs and recovering power from liquid waste materials, the entire plant pays for itself within one year. (Original)

Influence of Process Parameters on Nitrogen Oxide Formation in

DEFF Research Database (Denmark)

Lans, Robert Pieter Van Der; Glarborg, Peter; Dam-Johansen, Kim

1997-01-01

This paper describes the influence of burner operating conditions, burner geometry and fuel parameters on the formation of nitrogen oxide during combustion of pulverized coal. Main attention has been paid to combustion test facilities with self-sustaining flames, while extensions have been made...... to full scale boilers and furnace modeling. Since coal combustion and flame aerodynamics have been reviewed earlier, these phenomena are only treated briefly....

Synthesis of Titanium Dioxide Nanoparticles Using a Double-Slit Curved Wall-Jet Burner

KAUST Repository

Ismail, Mohamed

2016-05-04

A novel double-slit curved wall-jet (DS-CWJ) burner was proposed and utilized for flame synthesis. This burner was comprised of double curved wall-jet nozzles with coaxial slits; the inner slit was for the delivery of titanium tetraisopropoxide (TTIP) precursor while the outer one was to supply premixed fuel/air mixture of ethylene (C2H4) or propane (C3H8). This configuration enabled rapid mixing between the precursor and reactants along the curved surface and inside the recirculation zone of the burner. Particle growth of titanium dioxide (TiO2) nanoparticles and their phases was investigated with varying equivalence ratio and Reynolds number. Flow field and flame structure were measured using particle image velocimetry (PIV) and OH planar laser-induced fluorescence (PLIF) techniques, respectively. The nanoparticles were characterized using high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and nitrogen adsorption Brunauer–Emmett–Teller (BET) for surface area analysis. The flow field consisted of a wall-jet region leading to a recirculation zone, an interaction jet region, followed by a merged-jet region. The DS-CWJ burner revealed appreciable mixing characteristics between the precursor and combustion gases near the nozzle regions, with a slight increase in the axial velocity due to the precursor injection. The precursor supply had a negligible effect on the flame structure. The burner produced a reasonably uniform size (13–18 nm) nanoparticles with a high BET surface area (>100 m2/g). The phase of TiO2 nanoparticles was mainly dependent on the equivalence ratio and fuel type, which impact flame height, heat release rate, and high temperature residence time of the precursor vapor. For ethylene flames, the anatase content increased with the equivalence ratio, whereas it decreased in the case of propane flames. The synthesized TiO2 nanoparticles exhibited high crystallinity and the anatase phase was dominant at high equivalence

The Effects of Combustion Parameters on Pollutant Emissions in a Porous Burner

Directory of Open Access Journals (Sweden)

Negin Moallemi Khiavi

2014-06-01

Full Text Available This paper reports a two-dimensional numerical prediction of premixed methane/air combustion in inert porous media. The two dimensional Navier-stokes equations, the two separate energy equations for solid and gas and conservation equations for chemical species are solved using finite volume method based on SIMPLE algorithm. The burner under study is a rectangular one with two different regions. First region is a preheating zone (low porosity matrix that followed by the actual combustion region (high porosity matrix. For simulating the chemical reactions, skeletal mechanism (26 species and 77 reactions is used. For studying the pollutant emissions in this porous burner, the effects of porous matrix properties, excess air ratio and inlet velocity are studied. The predicted gas temperature contour and pollutant formations are in good agreement with the available experimental data. The results indicate that the downstream of the burner should be constructed from materials with high conductivity, high convective heat transfer coefficient and high porosity in order to decrease the CO and NO emissions. Also, with increasing the inlet velocity of gas mixture and the excess air ratio, the pollutant emissions are decreased.

Catalyst dispersion and activity under conditions of temperature-staged liquefaction

Energy Technology Data Exchange (ETDEWEB)

Davis, A.; Schobert, H.H.; Mitchell, G.D.; Artok, L.

1993-02-01

This research program involves the investigation of the use of highly dispersed catalyst precursors for the pretreatment of coals by mild hydrogenation. During the course of this effort solvent preswelling of the coal was evaluated as a means of deeply impregnating catalysts into coal, active phases of catalysts under reaction conditions were studied and the impact of these techniques were evaluated during pretreatment and temperature-staged liquefaction. Two coals, a Texas subbituminous and a Utah high volatile A bituminous, were used to examine the effects of solvent swelling pretreatment and catalyst impregnation on conversion behavior at 275[degrees]C, representative of the first, low-temperature stage in a temperature-staged liquefaction reaction. Ferrous sulfate, iron pentacarbonyl, ammonium tetrathiomolybdate, and molybdenum hexacarbonyl were used as catalyst precursors. Without swelling pretreatment, impregnation of both coals increased conversion, mainly through increased yields of preasphaltenes.

ZZ WPPR-FR-MOX/BNCMK, Benchmark on Pu Burner Fast Reactor

International Nuclear Information System (INIS)

Garnier, J.C.; Ikegami, T.

1993-01-01

Description of program or function: In order to intercompare the characteristics of the different reactors considered for Pu recycling, in terms of neutron economy, minor actinide production, uranium content versus Pu burning, the NSC Working Party on Physics of Plutonium Recycling (WPPR) is setting up several benchmark studies. They cover in particular the case of the evolution of the Pu quality and Pu fissile content for Pu recycling in PWRs; the void coefficient in PWRs partly fuelled with MOX versus Pu content; the physics characteristics of non-standard fast reactors with breeding ratios around 0.5. The following benchmarks are considered here: - Fast reactors: Pu Burner MOX fuel, Pu Burner metal fuel; - PWRs: MOX recycling (bad quality Pu), Multiple MOX recycling

CFD analysis of the pulverized coal combustion processes in a 160 MWe tangentially-fired-boiler of a thermal power plant

Energy Technology Data Exchange (ETDEWEB)

Silva, Cristiano V. da; Beskow, Arthur B. [Universidade Regional Integrada do Alto Uruguai e das Misses (LABSIM/GEAPI/URI), Erechim, RS (Brazil). Dept. de Engenharia e Ciencia da Computacao. Grupo de Engenharia Aplicada a Processos Industriais], Emails: cristiano@uricer.edu.br, Arthur@uricer.edu.br; Indrusiak, Maria Luiza S. [Universidade do Vale do Rio dos Sinos (UNISINOS), Sao Leopoldo, RS (Brazil). Programa de Engenharia Mecanica], E-mail: sperbindrusiak@via-rs.net

2010-10-15

The strategic role of energy and the current concern with greenhouse effects, energetic and exegetic efficiency of fossil fuel combustion greatly enhance the importance of the studies of complex physical and chemical processes occurring inside boilers of thermal power plants. The state of the art in computational fluid dynamics and the availability of commercial codes encourage numeric studies of the combustion processes. In the present work the commercial software CFX Ansys Europe Ltd. was used to study the combustion of coal in a 160 MWe commercial thermal power plant with the objective of simulating the operational conditions and identifying factors of inefficiency. The behavior of the flow of air and pulverized coal through the burners was analyzed, and the three-dimensional flue gas flow through the combustion chamber and heat exchangers was reproduced in the numeric simulation. (author)

Structure of diffusion flames from a vertical burner

Science.gov (United States)

Mark A. Finney; Dan Jimenez; Jack D. Cohen; Isaac C. Grenfell; Cyle Wold

2010-01-01

Non-steady and turbulent flames are commonly observed to produce flame contacts with adjacent fuels during fire spread in a wide range of fuel bed depths. A stationary gas-fired burner (flame wall) was developed to begin study of flame edge variability along an analagous vertical fuel source. This flame wall is surrogate for a combustion interface at the edge of a deep...

Fuel staging tests at the Kymijaervi power plant

International Nuclear Information System (INIS)

Kivelae, M.; Rotter, H.; Virkki, J.

1990-01-01

The aim of this study was to measure nitrogen oxide (NO x ) emissions and find the methods to reduce them in plants using coal and natural gas as fuel. The tests involved were made at the Kymijaervi Power Plant, Lahti, Finland. Coal and natural gas was used alone or mixed. With natural gas when using flue gas recirculation, the NO x emission level dropped from 330 mg/m 3 down to 60 mg/m 3 . A negative side effect was that the flue gas temperature increased. At coal combustion and staged combustion, the flue gas recirculation had no significant effect on the NO x emission level. At coal combustion, the staging of combustion air halved the NO x emission but the combustibles increased strongly. With fuel staging, using coal as main fuel and gas as staging fuel, the NO x emission level was decreased from 340 mg/m 3 to 170 mg/m 3 . At the same time the combustibles increased 2 %- units. Also the flue gas temperature increased a little. At the tests, the proportion of natural gas was rather high, one third of the fuel energy input, but it could not be decreased, because the gas flow ratio was already too low to ensure good mixing

FY 1980 Report on results of Sunshine Project by Coal Group. Basic researches on coal liquefaction techniques by solvolysis; 1980 nendo sunshine keikaku sekitanhan hokokusho. Sekitan no solvolysis ekika gijutsu no kiso kenkyu

Energy Technology Data Exchange (ETDEWEB)

NONE

1981-07-01

The basic experimental researches were carried out for coal liquefaction by solvolysis. The studied items include hydrogenation conditions for treating the primary liquefied products, asphalt, pitch and model solvents (e.g., anthracene oil) in the presence of a commercial catalyst, solvolysis conditions for finely divided, molten coal using a hydrogenation recycled solvent, hydrotreating solvents, analysis of solvolysis-liquefied products, and liquefaction capacity of fractionated solvents for finely divided, molten coal. The studied items for separation of minerals include settlement at high temperature of the solid residue from the first liquefaction stage, and changed coal particle size distribution as a result of the first-stage liquefaction reactions in the presence of a hydrogenation solvent. The experimental study results indicate that conversion of finely divided molten coal into asphaltenes and preasphaltenes is notably accelerated in the phase-II coal liquefaction process by solvolysis, when a hydrotreating solvent is used for the first stage solvolysis process. (NEDO)

Coal Matrix Deformation and Pore Structure Change in High-Pressure Nitrogen Replacement of Methane

Directory of Open Access Journals (Sweden)

Xiaofeng Ji

2018-01-01

Full Text Available Coal matrix deformation is one of the main controlling factors for coal reservoir permeability changes in nitrogen foam fracturing. The characteristics and mechanism of coal matrix deformation during the process of adsorption/desorption were studied by isothermal adsorption/desorption experiments with methane and nitrogen. Based on the free-energy theories, the Langmuir equation, and elastic mechanics, mathematical models of coal matrix deformation were developed and the deformation characteristics in adsorption/desorption processes were examined. From the study, we deduced that the coal matrix swelling, caused by methane adsorption, was a Langmuir-type relationship with the gas pressure, and exponentially increased as the adsorption quantity increased. Then, the deformation rate and amplitude of the coal matrix decreased gradually with the increase of the pressure. At the following stage, where nitrogen replaces methane, the coal matrix swelling continued but the deformation amplitude decreased, which was only 19.60% of the methane adsorption stage. At the mixed gas desorption stage, the coal matrix shrank with the reduction of pressure and the shrinkage amount changed logarithmically with the pressure, which had the hysteresis effect when compared with the swelling in adsorption. The mechanism of coal matrix deformation was discussed through a comparison of the change of micropores, mesopores, and also part macropores in the adsorption process.

Curved wall-jet burner for synthesizing titania and silica nanoparticles

KAUST Repository

Ismail, Mohamed; Memon, Nasir; Mansour, Morkous S.; Anjum, Dalaver H.; Chung, Suk-Ho

2015-01-01

A novel curved wall-jet (CWJ) burner was designed for flame synthesis, by injecting precursors through a center tube and by supplying fuel/air mixtures as an annular-inward jet for rapid mixing of the precursors in the reaction zone. Titanium

Test and evaluate the tri-gas low-Btu coal-gasification process. Final report, October 21, 1977-October 31, 1980

Energy Technology Data Exchange (ETDEWEB)

Zabetakis, M.G.

1980-12-01

This report describes the continuation of work done to develop the BCR TRI-GAS multiple fluidized-bed gasification process. The objective is the gasification of all ranks of coals with the only product being a clean, low-Btu fuel gas. Design and construction of a 100 lb/h process and equipment development unit (PEDU) was completed on the previous contract. The process consists of three fluid-bed reactors in series, each having a specific function: Stage 1 - pretreatment; Stage 2- - gasification; Stage 3 - maximization of carbon utilization. Under the present contract, 59 PEDU tests have been conducted. A number of these were single-stage tests, mostly in Stage 1; however, integrated PEDU tests were conducted with a western coal (Rosebud) and two eastern coals (Illinois No. 6 and Pittsburgh seam). Both Rosebud and Pittsburgh seam coals were gasified with the PEDU operating in the design mode. Operation with Illinois No. 6 seam coal was also very promising; however, time limitations precluded further testing with this coal. One of the crucial tasks was to operate the Stage 1 reactor to pretreat and devolatilize caking coals. By adding a small amount of air to the fluidizing gas, the caking properties of the coal can be eliminated. However, it was also desirable to release a high percentage of the volatile matter from the coal in this vessel. To accomplish this, the reactor had to be operated above the agglomerating temperature of caking coals. By maintaining a low ratio of fresh to treated coal, this objective was achieved. Both Illinois No. 6 and Pittsburgh seam coals were treated at temperatures of 800 to 900 F without agglomerating in the vessel.

The impact of resource tax reform on China's coal industry

International Nuclear Information System (INIS)

Liu, Huihui; Chen, ZhanMing; Wang, Jianliang; Fan, Jihong

2017-01-01

Contributing to approximately two-thirds of primary energy consumption, coal usage is the focus of China's energy policies. To regulate the resource taxation system and reduce the burden of coal enterprises, the Chinese government launched a reform of its resource tax system in 2014 for coal, introducing the ad valorem system to replace the volume-based system that had been in place for the preceding thirty years. To assess the impact of the tax reform, this paper constructs two-stage dynamic game models by taking the coal and coal-fired power industries as the players. The market situations of shortage and oversupply are investigated separately. Empirical data are collected to estimate the model parameters for numerical simulations. The model results suggest that the tax reform will reduce both coal prices and the coal industry profitability if the tax levied on each ton of coal is maintained at the same level as before the reform, regardless of whether the market is in a shortage or an oversupply situation. However, the increased buyer's power will amplify the effect of the tax reform. The numerical simulations also provide an estimation of the tax rate of the ad valorem system that maintains the profit of the coal industry. Considering the demand and supply situations in China's coal market, policy recommendations are provided to guide further reform of China's resource tax system. - Highlights: • The paper examines the influence of resource tax reform on China's coal industry. • We construct two-stage game models between coal and coal-fired power industries. • Market situations of shortage and oversupply are studied in two taxation systems. • Coal price will decrease if maintaining the tax levied on each ton of coal the same. • To achieve the reform objective, the ad valorem tax rate should not be set too high.

Effect of Low Frequency Burner Vibrations on the Characteristics of Jet Diffusion Flames

Directory of Open Access Journals (Sweden)

C. Kanthasamy

2012-03-01

Full Text Available Mechanical vibrations introduced in diffusion flame burners significantly affect the flame characteristics. In this experimental study, the effects of axial vibrations on the characteristics of laminar diffusion flames are investigated systematically. The effect of the frequency and amplitude of the vibrations on the flame height oscillations and flame stability is brought out. The amplitude of flame height oscillations is found to increase with increase in both frequency and amplitude of burner vibrations. Vibrations are shown to enhance stability of diffusion flames. Although flame lifts-off sooner with vibrations, stability of the flame increases.

Study on the Low-Temperature Oxidation Law in the Co-Mining Face of Coal and Oil Shale in a Goaf—A Case Study in the Liangjia Coal Mine, China

Directory of Open Access Journals (Sweden)

Gang Wang

2018-01-01

Full Text Available The low-temperature oxidation law of coal and rock mass is the basis to study spontaneous combustion in goafs. In this paper, the low-temperature oxidation laws of coal, oil shale, and mixtures of coal and oil shale were studied by using laboratory programmed heating experiments combined with a field beam tube monitoring system. The results from the programmed heating experiments showed that the heat released from oil shale was less than that from coal. Coal had a lower carbon monoxide (CO-producing temperature than oil shale, and the mixture showed obvious inhibiting effects on CO production with an average CO concentration of about 38% of that for coal. Index gases were selected in different stages to determine the critical turning point temperature for each stage. The field beam tube monitoring system showed that the temperature field of the 1105 co-mining face of coal and oil shale in the goaf of the Liangjia Coal Mine presented a ladder-like distribution, and CO concentration was the highest for coal and lower for the mixture of coal and oil shale, indicating that the mixture of coal with oil shale had an inhibiting effect on CO production, consistent with the results from the programmed heating experiments.

The generation of resonant turbulence for a premixed burner

NARCIS (Netherlands)

Verbeek, Antonie Alex; Pos, R.C.; Stoffels, Genie G.M.; Geurts, Bernardus J.; van der Meer, Theodorus H.

2012-01-01

Is it possible to optimize the turbulent combustion of a low swirl burner by using resonance in turbulence? To that end an active grid is constructed that consists of two perforated disks of which one is rotating, creating a system of pulsating jets, which in the end can be used as a central

Ensemble Diffraction Measurements of Spray Combustion in a Novel Vitiated Coflow Turbulent Jet Flame Burner

Science.gov (United States)

Cabra, R.; Hamano, Y.; Chen, J. Y.; Dibble, R. W.; Acosta, F.; Holve, D.

2000-01-01

An experimental investigation is presented of a novel vitiated coflow spray flame burner. The vitiated coflow emulates the recirculation region of most combustors, such as gas turbines or furnaces; additionally, since the vitiated gases are coflowing, the burner allows exploration of the chemistry of recirculation without the corresponding fluid mechanics of recirculation. As such, this burner allows for chemical kinetic model development without obscurations caused by fluid mechanics. The burner consists of a central fuel jet (droplet or gaseous) surrounded by the oxygen rich combustion products of a lean premixed flame that is stabilized on a perforated, brass plate. The design presented allows for the reacting coflow to span a large range of temperatures and oxygen concentrations. Several experiments measuring the relationships between mixture stoichiometry and flame temperature are used to map out the operating ranges of the coflow burner. These include temperatures as low 300 C to stoichiometric and oxygen concentrations from 18 percent to zero. This is achieved by stabilizing hydrogen-air premixed flames on a perforated plate. Furthermore, all of the CO2 generated is from the jet combustion. Thus, a probe sample of NO(sub X) and CO2 yields uniquely an emission index, as is commonly done in gas turbine engine exhaust research. The ability to adjust the oxygen content of the coflow allows us to steadily increase the coflow temperature surrounding the jet. At some temperature, the jet ignites far downstream from the injector tube. Further increases in the coflow temperature results in autoignition occurring closer to the nozzle. Examples are given of methane jetting into a coflow that is lean, stoichiometric, and even rich. Furthermore, an air jet with a rich coflow produced a normal looking flame that is actually 'inverted' (air on the inside, surrounded by fuel). In the special case of spray injection, we demonstrate the efficacy of this novel burner with a

Development, testing, and demonstration of an optimal fine coal cleaning circuit

International Nuclear Information System (INIS)

Mishra, M.; Placha, M.; Bethell, P.

1995-01-01

The overall objective of this project is to improve the efficiency of fine coal cleaning. The project will be completed in two phases: bench-scale testing and demonstration of four advanced flotation cells and; in-plant proof-of-concept (POC) pilot plant testing of two flotation cells individually and in two-stage combinations. The goal is to ascertain if a two-stage circuit can result in reduced capital and operating costs while achieving improved separation efficiency. The plant selected for this project, Cyprus Emerald Coal Preparation plant, cleans 1200 tph of raw coal. The plant produces approximately 4 million tonnes of clean coal per year at an average as received energy content of 30.2 MJ/Kg (13,000 Btu/lb)

Development, testing, and demonstration of an optimal fine coal cleaning circuit

Energy Technology Data Exchange (ETDEWEB)

Mishra, M.; Placha, M.; Bethell, P. [and others

1995-11-01

The overall objective of this project is to improve the efficiency of fine coal cleaning. The project will be completed in two phases: bench-scale testing and demonstration of four advanced flotation cells and; in-plant proof-of-concept (POC) pilot plant testing of two flotation cells individually and in two-stage combinations. The goal is to ascertain if a two-stage circuit can result in reduced capital and operating costs while achieving improved separation efficiency. The plant selected for this project, Cyprus Emerald Coal Preparation plant, cleans 1200 tph of raw coal. The plant produces approximately 4 million tonnes of clean coal per year at an average as received energy content of 30.2 MJ/Kg (13,000 Btu/lb).

Optimization of gas mixing system of premixed burner based on CFD analysis

International Nuclear Information System (INIS)

Zhang, Tian-Hu; Liu, Feng-Guo; You, Xue-Yi

2014-01-01

Highlights: • New multi-ejectors gas mixing system for premixed combustion burner is provided. • Two measures are proposed to improve the flow uniformity at the outlet of GMS. • Small improvement of uniformity induces significant decrease of pollutant emission. • Uniformity of velocity and fuel–gas mixing of ejector increases 234.2% and 2.9%. • Uniformity of flow rate and fuel–gas mixing of ejectors increases 1.9% and 2.2%. - Abstract: The optimization of gas mixing system (GMS) of premixed burner is presented by Computational Fluid Dynamics (CFD) and the uniformity at the outlet of GMS is proved experimentally to have strong influence on pollutant emission. To improve the uniformity at the outlet of GMS, the eleven distribution orifice plates and a diversion plate are introduced. The quantified analysis shows that the uniformity at the outlet of GMS is improved significantly. With applying the distribution orifice plates, the uniformity of velocity and fuel–gas mixing of single ejector is increased by 234.2% and 2.9%, respectively. With applying the diversion plate, the uniformity of flow rate and fuel–gas mixing of different ejectors is increased by 1.9% and 2.2%, respectively. The optimal measures and geometrical parameters provide an applicable guidance for the design of commercial premixed burner

Fuel Evaporation in an Atmospheric Premixed Burner: Sensitivity Analysis and Spray Vaporization

Directory of Open Access Journals (Sweden)

Dávid Csemány

2017-12-01

Full Text Available Calculation of evaporation requires accurate thermophysical properties of the liquid. Such data are well-known for conventional fossil fuels. In contrast, e.g., thermal conductivity or dynamic viscosity of the fuel vapor are rarely available for modern liquid fuels. To overcome this problem, molecular models can be used. Currently, the measurement-based properties of n-heptane and diesel oil are compared with estimated values, using the state-of-the-art molecular models to derive the temperature-dependent material properties. Then their effect on droplet evaporation was evaluated. The critical parameters were liquid density, latent heat of vaporization, boiling temperature, and vapor thermal conductivity where the estimation affected the evaporation time notably. Besides a general sensitivity analysis, evaporation modeling in a practical burner ended up with similar results. By calculating droplet motion, the evaporation number, the evaporation-to-residence time ratio can be derived. An empirical cumulative distribution function is used for the spray of the analyzed burner to evaluate evaporation in the mixing tube. Evaporation number did not exceed 0.4, meaning a full evaporation prior to reaching the burner lip in all cases. As droplet inertia depends upon its size, the residence time has a minimum value due to the phenomenon of overshooting.

Characteristics of premixed flames stabilized in an axisymmetric curved-wall jet burner with tip modification

KAUST Repository

Kim, Daejoong

2009-11-10

The stabilization characteristics of premixed flames in an axisymmetric curved-wall jet burner have been experimentally investigated. This burner utilized the Coanda effect on top of a burner tip. The initially spherical burner tip was modified to a flat tip and a concave tip in order to improve flame stabilization by providing enough space for flow recirculation above the burner tip region. The flow characteristics have been visualized using a schlieren technique. Small-scale turbulence structure has been observed mainly in the interaction jet region (located downstream of the recirculation region) for large jet velocity (Reynolds number >11,500). An appreciable amount of air entrainment was exhibited from the half-angle of the jet spread, approximately 20. The averaged planar laser-induced fluorescence images of the flames for this large velocity demonstrated that the strong signal of OH radicals, representing reaction zones, existed in the recirculation zone, while it was weak in the interaction jet region due to intermittency and local extinction by the generation of small scale turbulence. The OH radical signals strengthened again in the merged jet region (downstream of the interaction jet region). In extreme cases of Reynolds number over 19,000, a unique flame exhibiting OH radicals only in the recirculation zone was observed for the concave tip. The flame stabilization has been mapped by varying jet velocity and equivalence ratio, and the result showed that the stabilization characteristics were improved appreciably from the initial spherical tip design, especially for rich mixtures. The flow fields measured by a laser Doppler velocimetry confirmed the existence of recirculation zone and the expansion of the recirculation zones for the modified tips. The temperature profile measured by a coherent anti-Stokes Raman spectroscopy exhibited an intermittent nature, especially near the recirculation zone.

Coal background paper. Coal demand

International Nuclear Information System (INIS)

1997-01-01

Statistical data are presented on coal demands in IEA and OECD member countries and in other countries. Coal coaking and coaking coal consumption data are tabulated, and IEA secretariat's coal demand projections are summarized. Coal supply and production data by countries are given. Finally, coal trade data are presented, broken down for hard coal, steam coal, coking coal (imports and export). (R.P.)

The generation of resonant turbulence for a premixed burner

NARCIS (Netherlands)

Verbeek, Antonie Alex; Pos, R.C.; Stoffels, Genie G.M.; Geurts, Bernardus J.; van der Meer, Th.H.

Is it possible to optimize the turbulent combustion of a low swirl burner by using resonance in turbu- lence? To that end an active grid is constructed that consists of two perforated disks of which one is rotat- ing, creating a system of pulsating jets, which in the end can be used as a central

Numerical study of geometric parameters effecting temperature and thermal efficiency in a premix multi-hole flat flame burner

International Nuclear Information System (INIS)

Saberi Moghaddam, Mohammad Hossein; Saei Moghaddam, Mojtaba; Khorramdel, Mohammad

2017-01-01

This paper investigates the geometric parameters related to thermal efficiency and pollution emission of a multi-hole flat flame burner. Recent experimental studies indicate that such burners are significantly influenced by both the use of distribution mesh and the size of the diameter of the main and retention holes. The present study numerically simulated methane-air premixed combustion using a two-step mechanism and constant mass diffusivity for all species. The results indicate that the addition of distribution mesh leads to uniform flow and maximum temperature that will reduce NOx emissions. An increase in the diameter of the main holes increased the mass flow which increased the temperature, thermal efficiency and NOx emissions. The size of the retention holes should be considered to decrease the total flow velocity and bring the flame closer to the burner surface, although a diameter change did not considerably improve temperature and thermal efficiency. Ultimately, under temperature and pollutant emission constraints, the optimum diameters of the main and retention holes were determined to be 5 and 1.25 mm, respectively. - Highlights: • Using distribution mesh led to uniform flow and reduced Nox pollutant by 53%. • 93% of total heat transfer occurred by radiation method in multi-hole burner. • Employing retention hole caused the flame become closer to the burner surface.

Coal preparation and coal cleaning in the dry process; Kanshiki sentaku to coal cleaning

Energy Technology Data Exchange (ETDEWEB)

Tanaka, Z; Morikawa, M; Fujii, Y [Okayama University, Okayama (Japan). Faculty of Engineering

1996-09-01

Because the wet process has a problem such as waste water treatment, coal cleaning in the dry process was discussed. When a fluidized bed (using glass beads and calcium carbonate) is utilized instead of the heavy liquid, the fluidized bed will have apparent density as the liquid does, whereas the relative relationship therewith determines whether a substance having been put into the fluidized bed will float or sink. This is utilized for coals. In addition, two powder constituents of A and B may be wanted to be separated using the fluidized extraction process (similar to the liquid-liquid extraction process). In such a case, a fluidized bed in which both constituents are mixed is added with a third constituent C (which will not mix with A, but mix well with B), where the constituents are separated into A and (B + C), and the (B + C) constituent is separated further by using a sieve. If coal has the coal content mixed with ash content and pulverized, it turns into particle groups which have distributions in grain size and density. Groups having higher density may contain more ash, and those having lower density less ash. In addition, the ash content depends also on the grain size. The ash content may be classified by using simultaneously wind classification (for density and grain size) and a sieve (for grain size). This inference may be expanded to consideration of constructing a multi-stage fluidized bed classification tower. 12 figs., 5 tabs.

Experimental Study on Properties of Methane Diffusion of Coal Block under Triaxial Compressive Stress

Science.gov (United States)

Zhao, Hong-Bao

2014-01-01

Taking the standard size coal block samples defined by ISRM as research objects, both properties of methane diffusion of coal block under triaxial compressive stress and characteristic influences caused by methane pressure were systematically studied with thermo-fluid-solid coupling with triaxial servocontrolled seepage equipment of methane-containing coal. The result shows the methane diffusion property of coal block under triaxial compressive stress was shown in four-stage as follow, first is sharply reduce stage, second is hyperbolic reduce stage, third is close to a fixed value stage, fourth stage is 0. There is a special point making the reduced rate of characteristic curve of methane diffusion speed become sharply small; the influences of shape of methane diffusion speed characteristic curve caused by methane pressure are not obvious, which only is shown in numerical size of methane diffusion speed. Test time was extended required by appear of the special point makes the reduce rate of methane diffusion speed become sharply small. The fitting four-phase relation of methane diffusion of coal block under triaxial compressive stress was obtained, and the idea is proposed that influences of the fitting four-phase relation caused by methane pressure were only shown in value of fitting parameters. PMID:25531000

Regenerative burner systems for batch furnaces in the steel industry; Regenerativbrenner fuer Doppel-P-Strahlheizrohre in einer Feuerverzinkungslinie

Energy Technology Data Exchange (ETDEWEB)

Georgiew, A. [Salzgitter Flachstahl GmbH, Salzgitter (Germany); Wuenning, J.G.; Bonnet, U. [WS Waermeprozesstechnik GmbH, Renningen (Germany)

2007-09-15

This article will describe the application of a new self regenerative burner in a continuous galvanizing line. After a brief introduction of the process line, the self regenerative burner will be described. Very high air preheat temperatures enable considerable energy savings and flameless oxidation suppresses the formation of NO{sub x}. (orig.)

Regenerative burner systems for batch furnaces in the steel industry; Regenerativbrenner fuer Doppel-P-Strahlheizrohre in einer Feuerverzinkungslinie

Energy Technology Data Exchange (ETDEWEB)

Georgiew, Alexander [Salzgitter Flachstahl GmbH, Salzgitter (Germany); Wuenning, Joachim G.; Bonnet, Uwe [WS Waermeprozesstechnik GmbH, Renningen (Germany)

2009-07-01

This article will describe the application of a new self regenerative burner in a continuous galvanizing line. After a brief introduction of the process line, the self regenerative burner will be described. Very high air preheat temperatures enable considerable energy savings and flameless oxidation suppresses the formation of NO{sub X}. (orig.)

Reducing coal miner absenteeism

Energy Technology Data Exchange (ETDEWEB)

Peters, R.H.; Clingan, M.R. (Bureau of Mines, PA (USA). Pittsburgh Research Center)

1989-09-01

High absenteeism at coal mines can seriously affect safety and hamper productivity. Several effective strategies for achieving high attendance which mine operators may not have considered are presented and a method is proposed for implementing programs for minimizing absenteeism among coal miners. The best strategies for improving attendance will vary according to the needs and circumstances of the particular mine, however, the process for establishing such a program is relatively invariant. A four-stage process is recommended; evaluate data from prior attendance records, communicate attendance goals and policy, develop and implement an attendance promotion program, and recycle. 12 refs., 5 figs.

Optimization of a premixed low-swirl burner for industrial applications

International Nuclear Information System (INIS)

Fable, S.E.; Cheng, R.K.

2000-01-01

This study was motivated by recent tests results showing that a 5cm i.d. low-swirl burner (LSB) stabilizes ultra-lean premixed turbulent flames up to 600kW. A parametric study has been performed to determine the optimum ultra-lean LSB configuration, i.e. one that will achieve low NOx and flame stability, for thermal input between 15kW to 150kW. Using Laser Doppler Velocimetry (LDV), non-reacting centerline velocity and rms fluctuation profiles were measured, and were found to show self-similar behavior. This self-similarity may explain why the flame remains stationary relative to the burner exit despite a change in bulk flow velocity from 5 to 90m/s. The recess distance of the swirler affects the shape of the mean and rms velocity profiles. Lean blow-off limits were also determined for various recess distances, and an optimum exit length was found that provides stable operation for ultra-lean flames

78 FR 49701 - Approval and Promulgation of Implementation Plans; Connecticut; Control of Visible Emissions...

Science.gov (United States)

2013-08-15

... Harbor 3.... Bridgeport/ Coal/Oil Operating Adaro Adaro Coal, Fairfield. Coal/Residual Oil. Electrostatic precipitator, Activated carbon injection, Pulse jet fabric filter baghouse, Low NOX Burner Technology w... by 52 percent, the maximum allowable NO X emission rate for existing coal-fired boilers was reduced...

Thermal behaviour and microanalysis of coal subbituminus

Science.gov (United States)

Heriyanti; Prendika, W.; Ashyar, R.; Sutrisno

2018-04-01

Differential scanning calorimetry (DSC) and X-ray powder diffraction (XRD) is used to study the thermal behaviour of sub-bituminous coal. The DSC experiment was performed in air atmosphere up to 125 °C at a heating rate of 25 °C min1. The DSC curve showed that the distinct transitional stages in the coal samples studied. Thermal heating temperature intervals, peak and dissociation energy of the coal samples were also determined. The XRD analysis was used to evaluate the diffraction pattern and crystal structure of the compounds in the coal sample at various temperatures (25-350 °C). The XRD analysis of various temperatures obtained compounds from the coal sample, dominated by quartz (SiO2) and corundum (Al2O3). The increase in temperature of the thermal treatment showed a better crystal formation.

Innovation Developments of Coal Chemistry Science in L.M. Litvinenko Institute of Physical-Organic Chemistry and Coal Chemistry of NAS of Ukraine

Directory of Open Access Journals (Sweden)

Shendrik, T.G.

2015-11-01

Full Text Available The article presents short historical review and innovation developments of Coal Chemistry Department of L.M. Litvinenko Institute, NAS of Ukraine connected with coal mine exploitation problems, search for decisions toward prevention of spontaneous combustion, dust control in mines, establishing structural chemical features of coal with different genesis and stages of metamorphism with the aim to develop new methods of their modification and rational use. The methods of obtaining inexpensive sorbents from Ukrainian raw materials (including carbon containing waste are proposed. The problems of modern coal chemistry science in IPOCC of NAS of Ukraine are outlined.

Fuel oil from low-temperature carbonization of coal

Energy Technology Data Exchange (ETDEWEB)

Thau, A

1941-01-01

A review has been given of German developments during the last 20 years. Four methods for the low-temperature carbonization of coal have been developed to the industrial stage; two involving the use of externally heated, intermittent, metallic chamber ovens; and two employing the principle of internal heating by means of a current of gas. Tar from externally heated retorts can be used directly as fuel oil, but that from internally heated retorts requires further treatment. In order to extend the range of coals available for low-temperature carbonization, and to economize metals, an externally heated type of retort constructed of ceramic material has been developed to the industrial stage by T. An excellent coke and a tar that can be used directly as fuel oil are obtained. The properties of the tar obtained from Upper Silesian coal are briefly summarized.

Shea meal and cotton stalk as potential fuels for co-combustion with coal.

Science.gov (United States)

Munir, S; Nimmo, W; Gibbs, B M

2010-10-01

The efficient management of waste biomass is an important environmental problem in agricultural countries. Often land-fill is the main disposal route with ramifications including CH(4) release having 21 times greater global warming potential per molecule than CO(2). Biomasses are considered to be CO(2)-neutral fuels when combusted. Moreover, they are renewable and covered by the renewable obligation scheme and eligible for certificates in the UK. The overall objective of the investigation is to assess the performance of selected biomass and coal co-firing under two different modes of operation, air-staging and fuel-staging with the benefit of reduced-NO(x) and SO(2) emissions in power plant. The biomasses chosen for the study, shea meal (SM) and cotton stalk (CS) have very different cellulose/lignin compositions and different reported thermal behaviour. A series of experiments have been carried out in a 20 kW, down fired combustor using coal, shea meal-coal and cotton stalk-coal blends under un-staged, air-staged and fuel-staged co-combustion configurations. For air-staging, an optimum value of primary zone stoichiometry SR(1)=0.9 was found. Keeping it fixed, the shea meal and cotton stalk content in the coal-biomass blends was set to 5%, 10% and 15% on thermal basis. NO reductions of 51% and 60% were achieved using SM and CS, respectively, with an optimum thermal biomass blending ratio (BBR) of 10%. The results obtained were compared with un-staged and air-staged results for coal without the addition of biomass. Similarly for fuel-staging, keeping the length of the reburn and burnout zone fixed, SM and CS were evaluated as reductive fuel using different reburn fuel fractions (R(ff)) of 5%, 10%, 15% and 20%. NO reductions of 83% and 84% were obtained with an optimum R(ff) of 15% with an optimum reburn zone stoichiometry of SR(2)=0.8 for both SM and CS, respectively. SO(2) reduction and char burnout efficiency were also evaluated. It was found that addition of

Coal gasification. Quarterly report, January--March 1977

Energy Technology Data Exchange (ETDEWEB)

None

1977-12-01

High-Btu natural gas has a heating value of 950 to 1,000 Btu per standard cubic foot, is composed essentially of methane, and contains virtually no sulfur, carbon monoxide, or free hydrogen. The conversion of coal to high-Btu gas requires a chemical and physical transformation of solid coal. However, because coal has widely differing chemical and physical properties, depending on where it is mined, it is difficult to process. Therefore, to develop the most suitable techniques for gasifying coal, ERDA, together with the American Gas Association is sponsoring the development of several advanced conversion processes. Although the basic coal-gasification chemical reactions are the same for each process, the processes under development have unique characteristics. A number of the processes for converting coal to high Btu and to low Btu gas have reached the pilot plant stage. The responsibility for designing, constructing and operating each of these pilot plants is defined and progress on each during the quarter is described briefly. The accumulation of data for a coal gasification manual and the development of mathematical models of coal gasification processes are reported briefly. (LTN)

An artificial intelligence treatment of devolatilization for pulverized coal and biomass in co-fired flames

Energy Technology Data Exchange (ETDEWEB)

Abbas, T.; Awais, M.M.; Lockwood, F.C. [Lahore University of Management & Science, Lahore (Pakistan)

2003-02-01

In most of the existing predictive procedures for devolatilization, combustion and emissions are modeled by a single-step, global chemical reaction, with the yield of volatile matter presumed to experience mixing-controlled combustion. Several more detailed multi-step coal devolatilization models have recently emerged. A common shortcoming of these models is that they require a large set of input data, involving kinetic parameters, gas precursor compositions, and additional parameters describing the coal's polymeric structure. The input data must be generated from an extensive series of experimental measurements for each coal of interest. Very significant computational expense and application restricted to coals, which have already been studied, are implied. All of these problems are exacerbated when coal blending or co-firing with renewable solid fuels, such as forest and agricultural waste, and sewage sludge, is considered. In this paper, a new approach based on neural networks is proposed; it is capable of handling a range of solid fuels. The model considers heating rate, fuel atomic ratios, and the temperature of the fuel particles to predict the volatiles released by the particles. The 'learning' properties of the model implicitly facilitate all the physical conditions, of devolatilization experiments, which were used during its training and validation phases. The neural-network model was implemented into an existing 3D CFD combustion code. The predictions for high- and low-NOx burners demonstrate improved prediction of in-flame data for reduced computational effort, one-fifth of that with the standard single-global-reaction devolatilization model. Its devolatilization predictions have also been compared with a detailed devolatilization model (FLASHCHAIN) and were found to be comparable.

Integration of a wood pellet burner and a Stirling engine to produce residential heat and power

International Nuclear Information System (INIS)

Cardozo, Evelyn; Erlich, Catharina; Malmquist, Anders; Alejo, Lucio

2014-01-01

The integration a Stirling engine with a pellet burner is a promising alternative to produce heat and power for residential use. In this context, this study is focused on the experimental evaluation of the integration of a 20 kW th wood pellet burner and a 1 kW e Stirling engine. The thermal power not absorbed by the engine is used to produce hot water. The evaluation highlights the effects of pellet type, combustion chamber length and cycling operation on the Stirling engine temperatures and thermal power absorbed. The results show that the position of the Stirling engine is highly relevant in order to utilize as much as possible of the radiative heat from the burner. Within this study, only a 5 cm distance change between the Stirling engine and the pellet burner could result in an increase of almost 100 °C in the hot side of the engine. However, at a larger distance, the temperature of the hot side is almost unchanged suggesting dominating convective heat transfer from the hot flue gas. Ash accumulation decreases the temperature of the hot side of the engine after some cycles of operation when a commercial pellet burner is integrated. The temperature ratio, which is the relation between the minimum and maximum temperatures of the engine, decreases when using Ø8 mm wood pellets in comparison to Ø6 mm pellets due to higher measured temperatures on the hot side of the engine. Therefore, the amount of heat supplied to the engine is increased for Ø8 mm wood pellets. The effectiveness of the engine regenerator is increased at higher pressures. The relation between temperature of the hot side end and thermal power absorbed by the Stirling engine is nearly linear between 500 °C and 660 °C. Higher pressure inside the Stirling engine has a positive effect on the thermal power output. Both the chemical and thermal losses increase somewhat when integrating a Stirling engine in comparison to a stand-alone boiler for only heat production. The overall efficiency

Catalyst dispersion and activity under conditions of temperature-staged liquefaction. Final report

Energy Technology Data Exchange (ETDEWEB)

Davis, A.; Schobert, H.H.; Mitchell, G.D.; Artok, L.

1993-02-01

This research program involves the investigation of the use of highly dispersed catalyst precursors for the pretreatment of coals by mild hydrogenation. During the course of this effort solvent preswelling of the coal was evaluated as a means of deeply impregnating catalysts into coal, active phases of catalysts under reaction conditions were studied and the impact of these techniques were evaluated during pretreatment and temperature-staged liquefaction. Two coals, a Texas subbituminous and a Utah high volatile A bituminous, were used to examine the effects of solvent swelling pretreatment and catalyst impregnation on conversion behavior at 275{degrees}C, representative of the first, low-temperature stage in a temperature-staged liquefaction reaction. Ferrous sulfate, iron pentacarbonyl, ammonium tetrathiomolybdate, and molybdenum hexacarbonyl were used as catalyst precursors. Without swelling pretreatment, impregnation of both coals increased conversion, mainly through increased yields of preasphaltenes.

The effectiveness of recirculating flue gasses on a gas-fuel oil boiler unit with hearth burners

Energy Technology Data Exchange (ETDEWEB)

Eremeev, V V; Kovalenko, A L; Kozlov, V G

1981-01-01

The results of investigating the effect of recirculating flue gasses on a TP-87 boiler (D = 420 tons per hour, 14 MPa, 560 C) with a hearth composition of four gas-fuel oil burners are presented. The heat-release rate of the volume of the furnace is 136 Kw per m/sup 3/; that if a cross section of the combustion chamber is 3.2 MW/m/sup 2/. The hot air temperature is 420 C. The tests were carried out during the combustion of M-100 petroleum oil which has a moisture content of 3 / 4% and a sulfur content of 2.4%. The pressure of the oil against the mechanical sprayers is 2.9-3.0 MPa at the rated load; the temperature is 125-130 C. The recirculation of the flue gasses was organized in order to expand the regulatory stress range and decrease the discharge of nitric oxides into the atmosphere. Moreover, flue gasses with a temperature of 330-370/sup 0/C were removed from a first-degree BE gas conduit, and, using two BGD-15.5 type exhaust fans, were fed into the annular channels around the burners. The calculated velocity of the gasses at the output of the burner is equal to 35 M/s; the air velocity is 64 M/s. It is shown that the TP-87 furnace--with fuel oil hearth burners and recirculation to obtain flue gasses into independent burner ducts--makes it possible to obtain a useful stress range during almost complete fuel oil combustion with minimal air exceses by maintaining the calculated temperature of the superheated vapor. Recirculating flue gasses in a duct around the burners constitutes an effective means of decreasing the discharge of nitric oxides, and of decreasing local heat stress on the screens. However, increasing the recirculation coefficient to 0.17 causes a 0.35% increase in the loss of heat with the departing gasses (the temperature of which increases by 7 C), and a 0.15% decrease in the heat flow rate for SN, which leads to an overall drop of approx. 0.5% in the efficiency coefficient of the boiler.

Study on HOPE Management Mode of Coal Enterprises Based on Systematic Thinking

Science.gov (United States)

Zhaoran, Zhang; Tianzhu, Zhang; Wenjing, Tong

2018-02-01

The extensive management mode of coal enterprises is no longer applicable to the demand of enterprise development under the new economic situation. Combined with the characteristics of coal mine production, based on the system of thinking, integration of lean, people, comprehensive, job management theory, formed HOPE management model, including a core system and three support systems and 18 elements. There are three stages in the development and implementation of this model. To 6S site management for the initial stage to job process reengineering for the intermediate stage to post value process control for the advanced stage. The successful implementation of HOPE model in coal enterprises needs comprehensive control from five aspects: lean culture construction, flattening organizational structure, cost control system, performance appraisal system and lean information management platform. HOPE model can be implemented smoothly and make “win-win” between enterprises and employees.

The nexus of the coal industry and the state in Australia: Historical dimensions and contemporary challenges

International Nuclear Information System (INIS)

Baer, Hans A.

2016-01-01

This article presents a historical account of the close relationship between the coal mining industry and the federal and various state governments, thus over time building a state/coal industry nexus in Australia. It examines (1) an early colonial stage extending from the late 18th century to around the time of Federation in 1902 when the nexus emerged; (2) an intermediate stage from the early 20th century to the late 1970s when the nexus became solidified; and (3) a late stage from the early 1980s to the present day when the corporate sector came to dominate the nexus. Both Coalition and Australian Labor Party governments have consistently supported the exploitation of Australia's coal and natural gas, including recently coal seam gas, and supported the expansion of coal ports. An opposition movement has called for leaving coal and coal seam gas in the ground and shifting Australia’s energy production to renewable sources, particularly solar and wind energy. The article highlights how the nexus between coal mining and the state inhibits action on climate change. It argues this can be transcended by energy policy directed at socializing coal mining, wedded to a program of transitioning it to renewable energy production. - Highlights: • A close nexus exists between the coal industry and the state in Australia. • An anti-coal movement has developed in recent years in Australia. • Breaking the coal industry/state nexus requires socialization of energy production. • This would enable a shift from reliance on coal to renewable energy sources.

Modeling of complex premixed burner systems by using flamelet-generated manifolds

NARCIS (Netherlands)

Oijen, van J.A.; Lammers, F.A.; Goey, de L.P.H.

2001-01-01

The numerical modeling of realistic burner systems puts a very high demand on computational recources.The computational cost of combustion simulations can be reduced by reduction techniques which simplify the chemical kinetics. In this paper the recently introduced Flamelet-Generated Manifold method

Numerical investigation of premixed combustion in a porous burner with integrated heat exchanger

Energy Technology Data Exchange (ETDEWEB)

Farzaneh, Meisam; Shafiey, Mohammad; Shams, Mehrzad [K.N. Toosi University of Technology, Department of Mechanical Engineering, Tehran (Iran, Islamic Republic of); Ebrahimi, Reza [K.N. Toosi University of Technology, Department of Aerospace Engineering, Tehran (Iran, Islamic Republic of)

2012-07-15

In this paper, we perform a numerical analysis of a two-dimensional axisymmetric problem arising in premixed combustion in a porous burner with integrated heat exchanger. The physical domain consists of two zones, porous and heat exchanger zones. Two dimensional Navier-Stokes equations, gas and solid energy equations, and chemical species transport equations are solved and heat release is described by a multistep kinetics mechanism. The solid matrix is modeled as a gray medium, and the finite volume method is used to solve the radiative transfer equation to calculate the local radiation source/sink in the solid phase energy equation. Special attention is given to model heat transfer between the hot gas and the heat exchanger tube. Thus, the corresponding terms are added to the energy equations of the flow and the solid matrix. Gas and solid temperature profiles and species mole fractions on the burner centerline, predicted 2D temperature fields, species concentrations and streamlines are presented. Calculated results for temperature profiles are compared to experimental data. It is shown that there is good agreement between the numerical solutions and the experimental data and it is concluded that the developed numerical program is an excellent tool to investigate combustion in porous burner. (orig.)

Steam coal mines of tomorrow

Energy Technology Data Exchange (ETDEWEB)

McCloskey, G

1986-07-01

A comprehensive review of new steam coal mines being planned or developed worldwide. It shows that at least 20 major mines with a combined annual output of 110 million tonnes per annum, could add their coal to world markets in the next 10 years. The review highlights: substantial activity in Australia with at least four major mines at advanced planning stages; a strengthening of the South American export industry with 4 major mines operating in 10 years compared with just one today; no major export mines being developed in the traditional US mining areas; and the emergence of Indonesia as a major steam coal producer/exporter. The review also shows a reduction in cost/output ratios, and also the proximity of the new mines to existing infrastructure (e.g. export terminals, rail links).

Reduction of exposure to ultrafine particles by kitchen exhaust hoods: the effects of exhaust flow rates, particle size, and burner position.

Science.gov (United States)

Rim, Donghyun; Wallace, Lance; Nabinger, Steven; Persily, Andrew

2012-08-15

Cooking stoves, both gas and electric, are one of the strongest and most common sources of ultrafine particles (UFP) in homes. UFP have been shown to be associated with adverse health effects such as DNA damage and respiratory and cardiovascular diseases. This study investigates the effectiveness of kitchen exhaust hoods in reducing indoor levels of UFP emitted from a gas stove and oven. Measurements in an unoccupied manufactured house monitored size-resolved UFP (2 nm to 100 nm) concentrations from the gas stove and oven while varying range hood flow rate and burner position. The air change rate in the building was measured continuously based on the decay of a tracer gas (sulfur hexafluoride, SF(6)). The results show that range hood flow rate and burner position (front vs. rear) can have strong effects on the reduction of indoor levels of UFP released from the stove and oven, subsequently reducing occupant exposure to UFP. Higher range hood flow rates are generally more effective for UFP reduction, though the reduction varies with particle diameter. The influence of the range hood exhaust is larger for the back burner than for the front burner. The number-weighted particle reductions for range hood flow rates varying between 100 m(3)/h and 680 m(3)/h range from 31% to 94% for the front burner, from 54% to 98% for the back burner, and from 39% to 96% for the oven. Copyright © 2012 Elsevier B.V. All rights reserved.

Advanced coal-fueled gas turbine systems

Energy Technology Data Exchange (ETDEWEB)

Wenglarz, R.A.

1994-08-01

Several technology advances since the early coal-fueled turbine programs that address technical issues of coal as a turbine fuel have been developed in the early 1980s: Coal-water suspensions as fuel form, improved methods for removing ash and contaminants from coal, staged combustion for reducing NO{sub x} emissions from fuel-bound nitrogen, and greater understanding of deposition/erosion/corrosion and their control. Several Advanced Coal-Fueled Gas Turbine Systems programs were awarded to gas turbine manufacturers for for components development and proof of concept tests; one of these was Allison. Tests were conducted in a subscale coal combustion facility and a full-scale facility operating a coal combustor sized to the Allison Model 501-K industrial turbine. A rich-quench-lean (RQL), low nitrogen oxide combustor design incorporating hot gas cleanup was developed for coal fuels; this should also be applicable to biomass, etc. The combustor tests showed NO{sub x} and CO emissions {le} levels for turbines operating with natural gas. Water washing of vanes from the turbine removed the deposits. Systems and economic evaluations identified two possible applications for RQL turbines: Cogeneration plants based on Allison 501-K turbine (output 3.7 MW(e), 23,000 lbs/hr steam) and combined cycle power plants based on 50 MW or larger gas turbines. Coal-fueled cogeneration plant configurations were defined and evaluated for site specific factors. A coal-fueled turbine combined cycle plant design was identified which is simple, compact, and results in lower capital cost, with comparable efficiency and low emissions relative to other coal technologies (gasification, advanced PFBC).

Primary migration of Jurassic coal-derived oil in Santanghu basin

Energy Technology Data Exchange (ETDEWEB)

Zhang, W.; Zhong, N.; Ren, D. [China University of Mining and Technology, Beijing (China). Dept of Resource Exploitation Engineering

2000-11-01

It is known that the differential evolution of the multiple macerals results in 'oil generation by stage', and that 'early generation, early expulsion' is one of the preconditions for the efficient accumulation of the coal-derived oil. Based upon the study on the evolution of the physical properties, related to the hydrocarbon expulsion, of the Jurassic organic rock in Santanghu basin during the course of maturation, the mechanism of the primary migration of its coal-derived oil was discussed. The rapid loss of the inherent moisture in the organic rock was not accordant with the main generation stage of the coal-derived oil, so it was unrealistic that the oil migrated by dissolution in the expelled water. It is thought that the special forming mechanism of the continuous 'bitumen network' under the condition of over-pressure and an earlier history of primary migration may be essential to the Jurassic coal-derived oil in Santanghu basin. 17 refs., 4 figs.

The effects of chemical kinetics and wall temperature on performance of porous media burners

Science.gov (United States)

mohammadi, Iman; Hossainpour, Siamak

2013-06-01

This paper reports a two-dimensional numerical prediction of premixed methane-air combustion in inert porous media burner by using of four multi-step mechanisms: GRI-3.0 mechanism, GRI-2.11 mechanism and the skeletal and 17 Species mechanisms. The effects of these models on temperature, chemical species and pollutant emissions are studied. A two-dimensional axisymmetric model for premixed methane-air combustion in porous media burner has developed. The finite volume method has used to solve the governing equations of methane-air combustion in inert porous media burner. The results indicate that the present four models have the same accuracy in predicting temperature profiles and the difference between these profiles is not more than 2 %. In addition, the Gri-3.0 mechanism shows the best prediction of NO emission in comparison with experimental data. The 17 Species mechanism shows good agreement in prediction of temperature and pollutant emissions with GRI-3.0, GRI-2.11 and the skeletal mechanisms. Also the effects of wall temperature on the gas temperature and mass fraction of species such as NO and CH4 are studied.

Distinctive features of high-ash bituminuos coals combution with low milling fineness in furnace chambers with bottom blowing

Science.gov (United States)

Zroychikov, N. A.; Kaverin, A. A.; Biryukov, Ya A.

2017-11-01

Nowadays the problem of improvement of pulverized coal combustion schemes is an actual one for national power engineering, especially for combustion of coals with low milling fineness with significant portion of moisture or mineral impurities. In this case a big portion of inert material in the fuel may cause impairment of its ignition and combustion. In addition there are a lot of boiler installations on which nitrogen oxides emission exceeds standard values significantly. Decreasing of milling fineness is not without interest as a way of lowering an electric energy consumption for pulverization, which can reach 30% of power plant’s auxiliary consumption of electricity. Development of a combustion scheme meeting the requirements both for effective coal burning and environmental measures (related to NOx emission) is a complex task and demands compromising between these two factors, because implementation of NOx control by combustion very often leads to rising of carbon-in-ash loss. However widespread occurrence of such modern research technique as computer modeling allows to conduct big amount of variants calculations of combustion schemes with low cost and find an optimum. This paper presents results of numerical research of combined schemes of coal combustion with high portion of inert material based on straight-flow burners and nozzles. Several distinctive features of furnace aerodynamics, heat transfer and combustion has been found. The combined scheme of high-ash bituminouos coals combustion with low milling fineness, which allows effective combustion of pointed type of fuels with nitrogen oxides emission reduction has been proposed.

Comparison of In-Vessel Shielding Design Concepts between Sodium-cooled Fast Burner Reactor and the Sodium-cooled Fast Breeder Reactor

International Nuclear Information System (INIS)

Yun, Sunghwan; Kim, Sang Ji

2015-01-01

In this study, quantities of in-vessel shields were derived and compared each other based on the replaceable shield assembly concept for both of the breeder and burner SFRs. Korean Prototype Gen-IV Sodium-cooled Fast Reactor (PGSFR) like SFR was used as the reference reactor and calculation method reported in the reference was used for shielding analysis. In this paper, characteristics of in-vessel shielding design were studied for the burner SFR and breeder SFR based on the replaceable shield assembly concept. An in-vessel shield to prevent secondary sodium activation (SSA) in the intermediate heat exchangers (IHXs) is one of the most important structures for the pool type Sodium-cooled Fast Reactor (SFR). In our previous work, two in-vessel shielding design concepts were compared each other for the burner SFR. However, a number of SFRs have been designed and operated with the breeder concept, in which axial and radial blankets were loaded for fuel breeding, during the past several decades. Since axial and radial blanket plays a role of neutron shield, comparison of required in-vessel shield amount between the breeder and burner SFRs may be an interesting work for SFR designer. Due to the blanket, the breeder SFR showed better performance in axial neutron shielding. Hence, 10.1 m diameter reactor vessel satisfied the design limit of SSA at the IHXs. In case of the burner SFR, due to more significant axial fast neutron leakage, 10.6 m diameter reactor vessel was required to satisfy the design limit of SSA at the IHXs. Although more efficient axial shied such as a mixture of ZrH 2 and B 4 C can improve shielding performance of the burner SFR, additional fabrication difficulty may mitigate the advantage of improved shielding performance. Therefore, it can be concluded that the breeder SFR has better characteristic in invessel shielding design to prevent SSA at the IHXs than the burner SFR in the pool-type reactor

ESTIMATION OF NEAR SUBSURFACE COAL FIRE GAS EMISSIONS BASED ON GEOPHYSICAL INVESTIGATIONS

Science.gov (United States)

Chen-Brauchler, D.; Meyer, U.; Schlömer, S.; Kus, J.; Gundelach, V.; Wuttke, M.; Fischer, C.; Rueter, H.

2009-12-01

Spontaneous and industrially caused subsurface coal fires are worldwide disasters that destroy coal resources, cause air pollution and emit a large amount of green house gases. Especially in developing countries, such as China, India and Malaysia, this problem has intensified over the last 15 years. In China alone, 10 to 20 million tons of coal are believed to be lost in uncontrolled coal fires. The cooperation of developing countries and industrialized countries is needed to enforce internationally concerted approaches and political attention towards the problem. The Clean Development Mechanism (CDM) under the framework of the Kyoto Protocol may provide an international stage for financial investment needed to fight the disastrous situation. A Sino-German research project for coal fire exploration, monitoring and extinction applied several geophysical approaches in order to estimate the annual baseline especially of CO2 emissions from near subsurface coal fires. As a result of this project, we present verifiable methodologies that may be used in the CDM framework to estimate the amount of CO2 emissions from near subsurface coal fires. We developed three possibilities to approach the estimation based on (1) thermal energy release, (2) geological and geometrical determinations as well as (3) direct gas measurement. The studies involve the investigation of the physical property changes of the coal seam and bedrock during different burning stages of a underground coal fire. Various geophysical monitoring methods were applied from near surface to determine the coal volume, fire propagation, temperature anomalies, etc.

Experience from performance testing of low NOx burners for refinery heaters; Tests de performance avec des bruleurs de raffinerie a basse emission de NOx

Energy Technology Data Exchange (ETDEWEB)

Boden, J.C. [Refining Technology, BP Oil International, Sunbury (United Kingdom)

2001-07-01

Developments in low NOx burner technology have resulted in major reductions in NOx emissions from refinery process heaters. However, the techniques used in low NOx burners to reduce NOx emissions can potentially affect other key aspects of burner performance, particularly flame stability and completeness of combustion. BP has evaluated many of the currently available low and ultra-low NOx burners, both natural and forced draught, in its purpose-built test furnace. This extensive test programme has shown that to be a reliable predictor of actual performance a test rig must recreate accurately the real furnace conditions, particularly with respect to furnace and hearth temperatures. The testing has demonstrated the NOx emissions to be expected in practice from different generic types of burner, conventional, low NOx and ultra-low NOx, and has highlighted the sets of conditions most likely to lead to combustion performance problems. (authors)

Blow-off characteristics of turbulent premixed flames in curved-wall Jet Burner

KAUST Repository

Mansour, Morkous S.; Mannaa, O.; Chung, Suk-Ho

2015-01-01

and simultaneously stereoscopic particle image velocimetry (SPIV) quantified the turbulent flow field features. Ethylene/air flames were stabilized in CWJ burner to determine the sequence of events leading to blowoff. For stably burning flames far from blowoff

Role of the outer-edge flame on flame extinction in nitrogen-diluted non-premixed counterflow flames with finite burner diameters

KAUST Repository

Chung, Yong Ho

2013-03-01

This study of nitrogen-diluted non-premixed counterflow flames with finite burner diameters investigates the important role of the outer-edge flame on flame extinction through experimental and numerical analyses. It explores flame stability diagrams mapping the flame extinction response of nitrogen-diluted non-premixed counterflow flames to varying global strain rates in terms of burner diameter, burner gap, and velocity ratio. A critical nitrogen mole fraction exists beyond which the flame cannot be sustained; the critical nitrogen mole fraction versus global strain rate curves have C-shapes for various burner diameters, burner gaps, and velocity ratios. At sufficiently high strain-rate flames, these curves collapse into one curve; therefore, the flames follow the one-dimensional flame response of a typical diffusion flame. Low strain-rate flames are significantly affected by radial conductive heat loss, and therefore flame length. Three flame extinction modes are identified: flame extinction through shrinkage of the outer-edge flame with or without oscillations at the outer-edge flame prior to the extinction, and flame extinction through a flame hole at the flame center. The extinction modes are significantly affected by the behavior of the outer-edge flame. Detailed explanations are provided based on the measured flame-surface temperature and numerical evaluation of the fractional contribution of each term in the energy equation. Radial conductive heat loss at the flame edge to ambience is the main mechanism of extinction through shrinkage of the outer-edge flame in low strain-rate flames. Reduction of the burner diameter can extend the flame extinction mode by shrinking the outer-edge flame in higher strain-rate flames. © 2012 Elsevier Ltd. All rights reserved.

International Coal Report's coal year 1991

Energy Technology Data Exchange (ETDEWEB)

McCloskey, G [ed.

1991-05-31

Following introductory articles on factors affecting trade in coal and developments in the freight market, tables are given for coal exports and coal imports for major countries worldwide for 1989 and 1990. Figures are also included for coal consumption in Canada and the Eastern bloc,, power station consumption in Japan, coal supply and demand in the UK, electric utility coal consumption and stocks in the USA, coal production in Australia, Canada and USA by state, and world hard coal production. A final section gives electricity production and hard coal deliveries in the EEC, sales of imported and local coal and world production of pig iron and steel.

Distribution of volatile sulphur containing products during fixed bed pyrolysis and gasification of coals

Energy Technology Data Exchange (ETDEWEB)

Furimsky, E.

1991-08-01

Various coals were used to study the evolution of H{sub 2}S COS, and SO{sub 2} in a fixed bed reactor. For all types of coal, most of H{sub 2}S and SO{sub 2} were released during the devolatilization stage. COS was formed only during the gasification stage in the presence of CO{sub 2}.

Clean Coal Technologies in China: Current Status and Future Perspectives

Directory of Open Access Journals (Sweden)

Shiyan Chang

2016-12-01

Full Text Available Coal is the dominant primary energy source in China and the major source of greenhouse gases and air pollutants. To facilitate the use of coal in an environmentally satisfactory and economically viable way, clean coal technologies (CCTs are necessary. This paper presents a review of recent research and development of four kinds of CCTs: coal power generation; coal conversion; pollution control; and carbon capture, utilization, and storage. It also outlines future perspectives on directions for technology research and development (R&D. This review shows that China has made remarkable progress in the R&D of CCTs, and that a number of CCTs have now entered into the commercialization stage.

Correction of edge-flame propagation speed in a counterflow, annular slot burner

KAUST Repository

Tran, Vu Manh; Cha, Min

2015-01-01

to study the fundamental behaviors of edge-flames. In addition, our burner has easy optical access for detailed laser diagnostics. Flame displacement speeds were measured using a high-speed camera and related flow fields of unburned gases were visualized

The future development of the British coal topping cycles

International Nuclear Information System (INIS)

Harrison, J.S.; Dawes, S.G.; Minchener, A.J.

1992-01-01

In the United Kingdom (UK), at present most of the electricity produced from coal is generated using large pulverized fuel boilers with a conventional steam cycle. This technology has been developed over many years and has culminated in a 6 x 660 MWe station at Drax. The design cycle efficiency of such a station is some 40%, lower heating value basis, this limit being due to the nature of the Rankin cycle appropriate for steam turbines without utilization of the lower grade heat as in a combined heat and power (CHP) system. This paper reports that there is an increasing concern regarding the potential environmental impact of fossil-fuel fired systems. In particular, emissions limits are being tightened for particulates, NO x SO 2 . There is also concern over the greenhouse gases such as CO 2 . For existing conventional plant, this has resulted in the retrofitting of low NO x burners coupled in some instances with the introduction of flue gas desulphurization (FGD) equipment. Such modifications lead to significant increases in the capital and operating costs, with loss in cycle efficiency when FGD is fitted. Thus at Drax the efficiency will fall by some 1% to below 39%. These adverse effects have increased the need for alternative coal-fired generation systems which will have higher efficiencies while at the same time improving the environmental impact of the power stations. The environmental debate over the use of fossil fuels for power generation will continue, with continuing public uncertainty especially over the extent and causes of enhanced global warming. The debate will continue against a background of rising power generation demand worldwide, particularly in developing countries. What is clear is that in the absence of long-term, cost effective and technologically proven alternatives to fossil fuels, coal will remain the prime fuel for power generation

Pollutant Exposures from Natural Gas Cooking Burners: A Simulation-Based Assessment for Southern California

Energy Technology Data Exchange (ETDEWEB)

Logue, Jennifer M.; Klepeis, Neil E.; Lobscheid, Agnes B.; Singer, Brett C.

2014-06-01

Residential natural gas cooking burners (NGCBs) can emit substantial quantities of pollutants and they are typically used without venting. The objective of this study is to quantify pollutant concentrations and occupant exposures resulting from NGCB use in California homes. A mass balance model was applied to estimate time-dependent pollutant concentrations throughout homes and the "exposure concentrations" experienced by individual occupants. The model was applied to estimate nitrogen dioxide (NO{sub 2}), carbon monoxide (CO), and formaldehyde (HCHO) concentrations for one week each in summer and winter for a representative sample of Southern California homes. The model simulated pollutant emissions from NGCBs, NO{sub 2} and CO entry from outdoors, dilution throughout the home, and removal by ventilation and deposition. Residence characteristics and outdoor concentrations of CO and NO{sub 2} were obtained from available databases. Ventilation rates, occupancy patterns, and burner use were inferred from household characteristics. Proximity to the burner(s) and the benefits of using venting range hoods were also explored. Replicate model executions using independently generated sets of stochastic variable values yielded estimated pollutant concentration distributions with geometric means varying less than 10%. The simulation model estimates that in homes using NGCBs without coincident use of venting range hoods, 62%, 9%, and 53% of occupants are routinely exposed to NO{sub 2}, CO, and HCHO levels that exceed acute health-based standards and guidelines. NGCB use increased the sample median of the highest simulated 1-hr indoor concentrations by 100, 3000, and 20 ppb for NO{sub 2}, CO, and HCHO, respectively. Reducing pollutant exposures from NGCBs should be a public health priority. Simulation results suggest that regular use of even moderately effective venting range hoods would dramatically reduce the percentage of homes in which concentrations exceed health

Influence of the burner swirl on the azimuthal instabilities in an annular combustor

Science.gov (United States)

Mazur, Marek; Nygård, Håkon; Worth, Nicholas; Dawson, James

2017-11-01

Improving our fundamental understanding of thermoacoustic instabilities will aid the development of new low emission gas turbine combustors. In the present investigation the effects of swirl on the self-excited azimuthal combustion instabilities in a multi-burner annular annular combustor are investigated experimentally. Each of the burners features a bluff body and a swirler to stabilize the flame. The combustor is operated with an ethylene-air premixture at powers up to 100 kW. The swirl number of the burners is varied in these tests. For each case, dynamic pressure measurements at different azimuthal positions, as well as overhead imaging of OH* of the entire combustor are conducted simultaneously and at a high sampling frequency. The measurements are then used to determine the azimuthal acoustic and heat release rate modes in the chamber and to determine whether these modes are standing, spinning or mixed. Furthermore, the phase shift between the heat release rate and pressure and the shape of these two signals are analysed at different azimuthal positions. Based on the Rayleigh criterion, these investigations allow to obtain an insight about the effects of the swirl on the instability margins of the combustor. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant agreement n° 677931 TAIAC).

Cleaner Coal in China [Chinese Version

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-07-01

China’s rapid economic growth has aroused intense interest around the world. Policy makers, industrialists, investors, environmentalists, researchers and others want to better understand the issues that this populous nation faces as it further develops an already thriving economy largely fuelled by coal. This study sheds light on the Chinese coal supply and transformation sectors. China’s rapid economic growth has aroused intense interest around the world. Policy makers, industrialists, investors, environmentalists, researchers and others want to better understand the issues that this populous nation faces as it further develops an already thriving economy largely fuelled by coal. This study sheds light on the Chinese coal supply and transformation sectors. China’s coal, mined locally and available at a relatively low cost, has brought enormous benefits to energy consumers in China and to those outside the country who enjoy the products of its coal-based economy. Yet from another perspective, China’s coal use has a high cost. Despite progress, health and safety in the thousands of small coal mines lag far behind the standards achieved in China’s modern, large mines. Environmental degradation is a real and pressing problem at all stages of coal production, supply and use. Adding to these burdens, emissions of carbon dioxide are of concern to the Chinese government as it embarks on its own climate protection strategy. Technology solutions are already transforming the way coal is used in China and elsewhere. This study explores the context in which the development and deployment of these technologies can be accelerated. Providing a large amount of new data, it describes in detail the situation in China as well as the experiences of other countries in making coal cleaner. Above all, the report calls for much greater levels of collaboration – existing bi-lateral and multi-lateral co-operation with China on coal is found lacking. China’s growing openness

Design and construction of a regenerative radiant tube burner

International Nuclear Information System (INIS)

Henao, Diego Alberto; Cano C, Carlos Andres; Amell Arrieta, Andres A.

2002-01-01

The technological development of the gas industry in Colombia, aiming at efficient and safe use of the natural gas, requires the assimilation and adaptation of new generation, technologies for this purpose in this article results are presented on the design, construction and characterization of a prototype of a burner of regenerative radiant robe with a thermal power of 9,94 kW and a factor of air 1,05. This system takes advantage of the high exit temperature of the combustion smokes, after they go trough a metallic robe where they transfer the heat by radiation, to heat a ceramic channel that has the capacity to absorbing a part of the heat of the smokes and then transferring them to a current of cold air. The benefits of air heating are a saving in fuel, compared with other processes that don't incorporate the recovery of heat from the combustion gases. In this work it was possible to probe a methodology for the design of this type of burners and to reach maximum temperatures of heating of combustion air of 377,9 centigrade degrees, using a material available in the national market, whose regenerative properties should be studied in depth

Measurements of non-reacting and reacting flow fields of a liquid swirl flame burner

Science.gov (United States)

Chong, Cheng Tung; Hochgreb, Simone

2015-03-01

The understanding of the liquid fuel spray and flow field characteristics inside a combustor is crucial for designing a fuel efficient and low emission device. Characterisation of the flow field of a model gas turbine liquid swirl burner is performed by using a 2-D particle imaging velocimetry(PIV) system. The flow field pattern of an axial flow burner with a fixed swirl intensity is compared under confined and unconfined conditions, i.e., with and without the combustor wall. The effect of temperature on the main swirling air flow is investigated under open and non-reacting conditions. The result shows that axial and radial velocities increase as a result of decreased flow density and increased flow volume. The flow field of the main swirling flow with liquid fuel spray injection is compared to non-spray swirling flow. Introduction of liquid fuel spray changes the swirl air flow field at the burner outlet, where the radial velocity components increase for both open and confined environment. Under reacting condition, the enclosure generates a corner recirculation zone that intensifies the strength of radial velocity. The reverse flow and corner recirculation zone assists in stabilizing the flame by preheating the reactants. The flow field data can be used as validation target for swirl combustion modelling.

Report for fiscal 1981 of Sunshine Program coal group. Basic research on Solvolysis liquefaction technology; 1981 nendo solvolysis ekika gijutsu no kiso kenkyu hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1982-03-01

Basic research is conducted on the Solvolysis liquefaction process for the purpose of producing from coal an ashless, low-sulfur, pollution-free liquid fuel. In the research on the Solvolysis liquefaction (1st stage liquefaction) of coal using a hydrogenation solvent, the Solvolysis liquefaction of coal is studied, for which a refined Solvolysis pitch containing coal substances and a hydride of solvent refined coal are used as Solvolysis liquefaction solvents for the 1st stage. In the research on the 1st stage liquefaction reaction conditions using a high-temperature closed process, two methods are employed. One is a method that uses a mini-pump type reactor in which a small hermetic container is submerged in a high-temperature solvent for rapid heating and the other is a method that uses a pipe type reactor in which coal slurry is caused to travel through a pipe heated to a high temperature. For the analysis of the 2nd stage liquefaction (hydrogenation) reaction conditions, the properties of the 2nd coal liquid, and the constitution of the 2nd coal liquid, and the for the research on the 1st stage liquefaction capacity, the hydrogenation of anthracene oil and solvent refined coal as recyclable solvent models is studied. (NEDO)

Enterprise investment, local government intervention and coal overcapacity: The case of China

International Nuclear Information System (INIS)

Zhang, Yanfang; Zhang, Ming; Liu, Yue; Nie, Rui

2017-01-01

Long-term management of China's coal overcapacity depends on the targeted policy guidance on industry production capacity expansion in the overcapacity formation process. In this study, coal enterprise and local government are treated as game participants, and a three-stage dynamic game model has been developed to depict the boosting effect of the game behavior of coal enterprise's and local government's capacity investments in different markets of supply and demand. The results are shown in the following: (1) local government has been the 'behind-the-scenes' operator of over-investment and redundant construction, and its excessive interventions in coal industry investment have been the primary cause of overcapacity formation; (2) when the market is in short supply, coal enterprise's optimal behavior is to continuously increase the rate of investment growth until it reaches the threshold to obtain the maximum excess profits, ultimately leading to overinvestment in the industry; and (3) the key factors affecting the game abilities of coal enterprise and local government are the market's self-regulation and the central government's supervision intensity. Although the Chinese government, a highly vertically oriented bureaucratic structure, is implementing a mandatory de-capacity policy to alleviate the intensity of excessive coal capacity, it is not a long-term regularization on the supply-side reform. - Highlights: • The formation of China's coal overcapacity is studied from capacity investors. • A three-stage game is developed to depict the boosting effect of coal overcapacity. • Local government has been the 'behind-the-scenes' operators of coal overcapacity. • Coal enterprise's optimal strategy is reaching an investment-max with undersupply. • Chinese government should rely more on market mechanisms instead of intervention.

Low NO sub x /SO sub x Burner retrofit for utility cyclone boilers

Energy Technology Data Exchange (ETDEWEB)

1991-09-01

This Public Design Report provides available nonproprietary design information on the Low NO{sub x}SO{sub x} Burner Retrofit of Utility Cyclone Boilers project. In addition to the design aspects, the history of the project, the organization of the project, and the role of the funding parties are discussed. An overview of the Low NO{sub x}SO{sub x} (LNS) Burner, the cyclone boiler and the Southern Illinois Power Cooperative host site is presented. A detailed nonproprietary description of the individual process steps, plant systems, and resulting performance then follows. Narrative process descriptions, simplified process flow diagrams, input/output stream data, operating conditions and requirements are given for each unit. The plant demonstration program and start up provisions, the environmental considerations and control, monitoring and safety factors that are considered are also addressed.

Electric plants to gas, influence of both Mineral Matter and Air Oxidation in coal pyrolysis

International Nuclear Information System (INIS)

Mondragon, F.; Jaramillo, A.; Quintero, G.

1995-01-01

In this work some coal samples from different Colombia's deposits are analyzed. In first stage, material matter is removed from coal by acid treatment with HF/HCl, and aerial oxidation of coal is made with air in oven to 150 Centigrade degree temperature. In second stage, pyrolysis is carried out in two different techniques: 1. Thermogravimetric Analysis (TGA) and 2. Programmed Temperature Pyrolysis (PTP) in a pyrolyzer equipped with a quadrupole mass spectrometer. In both techniques, the coal samples are heated in different rates to 650 Centigrade degree. During PTP trials the evolution of CH4, H2S, hydrocarbons (m/z=42), CO2, benzene and toluene are monitored. Studied coal samples showed: 1). A gas conversion range between 48.8% to 21.8%; 2). A decrease in the gas conversion between 2% to 4%, when oxidation it is applied; 3). The temperature at the one which is presented the maximum evolution of CH4 is similar for all coal samples; 4). The maximum evolution of H2S depends on mineral matter composition, occurs between 480 to 550 Centigrade degrees and is presented due to pyrite decomposition. 5). The evolution of CO2 occurs between 100 to 650 Centigrade degree, its production is generated in different stage of the mentioned temperature range, and in some coal samples is presented due to inorganic origin

Clean coal use in China: Challenges and policy implications

International Nuclear Information System (INIS)

Tang, Xu; Snowden, Simon; McLellan, Benjamin C.; Höök, Mikael

2015-01-01

Energy consumption in China is currently dominated by coal, a major source of air pollution and carbon emissions. The utilization of clean coal technologies is a likely strategic choice for China at present, however, although there have been many successes in clean coal technologies worldwide, they are not widely used in China. This paper examines the challenges that China faces in the implementation of such clean coal technologies, where the analysis shows that those drivers that have a negative bearing on the utilization of clean coal in China are mainly non-technical factors such as the low legal liability of atmospheric pollution related to coal use, and the lack of laws and mandatory regulations for clean coal use in China. Policies for the development of clean coal technologies are in their early stages in China, and the lack of laws and detailed implementation requirements for clean coal require resolution in order to accelerate China's clean coal developments. Currently, environmental pollution has gained widespread attention from the wider Chinese populace and taking advantage of this opportunity provides a space in which to regain the initiative to raise people’s awareness of clean coal products, and improve enterprises’ enthusiasm for clean coal. - Highlights: • Clean coal is not widely used in China due to many management issues. • Legal liability of pollution related with coal utilization is too low in China. • China is lack of laws and mandatory regulations for clean coal utilization. • It is difficult to accelerate clean coal utilization by incentive subsidies alone.

Utility boiler computer modeling experience in the USA for practical furnace air port and low NOx burner field design

Energy Technology Data Exchange (ETDEWEB)

Breen, B.P.; Urich, J.A.; Krippene, B.C. [ESA, Inc. (United States)

2000-07-01

This paper presents several examples of where effective furnace and low NOx burner modeling has produced substantial advantages to the low NOx combustion system designer. Using practical boiler furnace air injection port and low NOx burner maths modeling as an integral part of the design process has often made the difference between a successful low NOx combustion system field conversion project and an unsuccessful one.

Modeling of pollutant formation in fully premixing surface burners using a verified practice-oriented experimental reaction-kinetic calculation method. Final report

International Nuclear Information System (INIS)

Ruy, C.; Kremer, H.

1996-01-01

The intent of the present study was to simulate quantitatively pollutant formation in premixing surface burners and to describe qualitatively the share of the premixing flame in pollut emissions from atmospheric burners. For this purpose reaction-kinetic programmes for one-dimensional premixing flames were extended by a terms describing heat discharge through gas radiation. Furthermore, the calculation range for the flame was extended far into the secondary reaction zone. Temperature, CO, and NO x profiles were measured in the secondary reaction zone of premixing burners at standard pressure. The air-fuel ratio was calculated within the practically relevant range between 0.5 and 1.5, as was load behaviour. (DG) [de

Nanometre-sized pores in coal: Variations between coal basins and coal origin

Science.gov (United States)

Sakurovs, Richard; Koval, Lukas; Grigore, Mihaela; Sokolava, Anna; Ruppert, Leslie F.; Melnichenko, Yuri B.

2018-01-01

We have used small angle neutron scattering (SANS) to investigate the differences in methane and hexane penetration in pores in bituminous coal samples from the U.S., Canada, South Africa, and China, and maceral concentrates from Australian coals. This work is an extension of previous work that showed consistent differences between the extent of penetration by methane into 10–20 nm size pores in inertinite in bituminous coals from Australia, North America and Poland.In this study we have confirmed that there are differences in the response of inertinite to methane and hexane penetration in coals sourced from different coal basins. Inertinite in Permian Australian coals generally has relatively high numbers of pores in the 2.5–250 nm size range and the pores are highly penetrable by methane and hexane; coals sourced from Western Canada had similar penetrability to these Australian coals. However, the penetrability of methane and hexane into inertinite from the Australian Illawarra Coal Measures (also Permian) is substantially less than that of the other Australian coals; there are about 80% fewer 12 nm pores in Illawarra inertinite compared to the other Australian coals examined. The inertinite in coals sourced from South Africa and China had accessibility intermediate between the Illawarra coals and the other Australian coals.The extent of hexane penetration was 10–20% less than CD4 penetration into the same coal and this difference was most pronounced in the 5–50 nm pore size range. Hexane and methane penetrability into the coals showed similar trends with inertinite content.The observed variations in inertinite porosity between coals from different coal regions and coal basins may explain why previous studies differ in their observations of the relationships between gas sorption behavior, permeability, porosity, and maceral composition. These variations are not simply a demarcation between Northern and Southern Hemisphere coals.

A numerical study of a premixed flame on a slit burner

NARCIS (Netherlands)

Somers, L.M.T.; Goey, de L.P.H.

1995-01-01

A numerical study of a premixed methane/air flame on a 4 mm slit burner is presented. A local grid refinement technique is used to deal with large gradients and curvature of all variables encountered in the flame, keeping the number of grid points within reasonable bounds. The method used here leads

Wabash River Coal Gasification Repowering Project: A DOE Assessment; FINAL

International Nuclear Information System (INIS)

National Energy Technology Laboratory

2002-01-01

The goal of the U.S. Department of Energy (DOE) Clean Coal Technology Program (CCT) is to furnish the energy marketplace with a number of advanced, more efficient, and environmentally responsible coal utilization technologies through demonstration projects. These projects seek to establish the commercial feasibility of the most promising advanced coal technologies that have developed beyond the proof-of-concept stage. This document serves as a DOE post-project assessment (PPA) of a project selected in CCT Round IV, the Wabash River Coal Gasification Repowering (WRCGR) Project, as described in a Report to Congress (U.S. Department of Energy 1992). Repowering consists of replacing an existing coal-fired boiler with one or more clean coal technologies to achieve significantly improved environmental performance. The desire to demonstrate utility repowering with a two-stage, pressurized, oxygen-blown, entrained-flow, integrated gasification combined-cycle (IGCC) system prompted Destec Energy, Inc., and PSI Energy, Inc., to form a joint venture and submit a proposal for this project. In July 1992, the Wabash River Coal Gasification Repowering Project Joint Venture (WRCGRPJV, the Participant) entered into a cooperative agreement with DOE to conduct this project. The project was sited at PSI Energy's Wabash River Generating Station, located in West Terre Haute, Indiana. The purpose of this CCT project was to demonstrate IGCC repowering using a Destec gasifier and to assess long-term reliability, availability, and maintainability of the system at a fully commercial scale. DOE provided 50 percent of the total project funding (for capital and operating costs during the demonstration period) of$438 million

FY 1999 basic survey of coal resource development. Coal GIS survey; 1999 nendo sekitan shigen kaihatsu kiso chosa. Sekitan GIS chosa

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

The purpose of this survey is to construct a comprehensive coal field assessment technology system which can promptly cope with any natural conditions/geological situations of coal field. As to the GIS (geographical information system) which can unifiedly manage/analyze various data being used in other fields, survey was conducted of present situations/technology trends of the resource related GIS, and at the same time the survey is aimed at applying it to the coal resource field. In the survey in this fiscal year, based on the survey made in FY 1998, applicability of GIS function was verified for Australia where the coal GIS is prepared. And the fundamental design was made to construct a coal GIS considered of concrete application in the stage of coal resource exploration and resource assessment. In the fundamental design, prototypes of individual functions of the system were made. Making the analysis using the actual data, expansion and complication of the system size were advanced step by step toward the completion of the system. Such prototypical development method was adopted. (NEDO)

A study of toxic emissions from a coal-fired power plant utilizing the SNOX innovative clean coal technology demonstration. Volume 1, Sampling/results/special topics: Final report

Energy Technology Data Exchange (ETDEWEB)

1994-07-01

This study was one of a group of assessments of toxic emissions from coal-fired power plants, conducted for DOE during 1993. The motivation for those assessments was the mandate in the 1990 Clean Air Act Amendments that a study be made of emissions of hazardous air pollutants (HAPs) from electric utilities. The report is organized in two volumes. Volume 1: Sampling describes the sampling effort conducted as the basis for this study; Results presents the concentration data on HAPs in the several power plant streams, and reports the results of evaluations and calculations conducted with those data; and Special Topics report on issues such as comparison of sampling methods and vapor/solid distributions of HAPs. Volume 2: Appendices include quality assurance/quality control results, uncertainty analysis for emission factors, and data sheets. This study involved measurements of a variety of substances in solid, liquid, and gaseous samples from input, output, and process streams at the Innovative Clean Coal Technology Demonstration (ICCT) of the Wet Sulfuric Acid-Selective Catalytic Reduction (SNOX) process. The SNOX demonstration is being conducted at Ohio Edison`s Niles Boiler No. 2 which uses cyclone burners to burn bituminous coal. A 35 megawatt slipstream of flue gas from the boiler is used to demonstrate SNOX. The substances measured at the SNOX process were the following: 1. Five major and 16 trace elements, including mercury, chromium, cadmium, lead, selenium, arsenic, beryllium, and nickel; 2. Acids and corresponding anions (HCl, HF, chloride, fluoride, phosphate, sulfate); 3. Ammonia and cyanide; 4. Elemental carbon; 5. Radionuclides; 6. Volatile organic compounds (VOC); 7. Semi-volatile compounds (SVOC) including polynuclear aromatic hydrocarbons (PAH); and 8. Aldehydes.

Fuel production from coal by the Mobil Oil process using nuclear high-temperature process heat

International Nuclear Information System (INIS)

Hoffmann, G.

1982-01-01

Two processes for the production of liquid hydrocarbons are presented: Direct conversion of coal into fuel (coal hydrogenation) and indirect conversion of coal into fuel (syngas production, methanol synthesis, Mobil Oil process). Both processes have several variants in which nuclear process heat may be used; in most cases, the nuclear heat is introduced in the gas production stage. The following gas production processes are compared: LURGI coal gasification process; steam reformer methanation, with and without coal hydrogasification and steam gasification of coal. (orig./EF) [de

Chemical and Pyrolytic Thermogravimetric Characterization of Nigerian Bituminous Coals

Directory of Open Access Journals (Sweden)

Nyakuma Bemgba Bevan

2016-12-01

Full Text Available The discovery of new coal deposits in Nigeria presents solutions for nation’s energy crises and prospects for socioeconomic growth and sustainable development. Furthermore, the quest for sustainable energy to limit global warming, climate change, and environmental degradation has necessitated the exploration of alternatives using cleaner technologies such as coal pyrolysis. However, a lack of comprehensive data on physico-chemical and thermal properties of Nigerian coals has greatly limited their utilization. Therefore, the physico-chemical properties, rank (classification, and thermal decomposition profiles of two Nigerian bituminous coals – Afuze (AFZ and Shankodi-Jangwa (SKJ – were examined in this study. The results indicate that the coals contain high proportions of C, H, N, S, O and a sufficiently high heating value (HHV for energy conversion. The coal classification revealed that the Afuze (AFZ coal possesses a higher rank, maturity, and coal properties compared to the Shankodi-Jangwa (SKJ coal. A thermal analysis demonstrated that coal pyrolysis in both cases occurred in three stages; drying (30-200 °C, devolatilization (200-600 °C, and char decomposition (600-1000 °C. The results also indicated that pyrolysis at 1000 °C is not sufficient for complete pyrolysis. In general, the thermochemical and pyrolytic fuel properties indicate that the coal from both places can potentially be utilized for future clean energy applications.

Behaviors of tribrachial edge flames and their interactions in a triple-port burner

KAUST Repository

Yamamoto, Kazuhiro; Isobe, Yusuke; Hayashi, Naoki; Yamashita, Hiroshi; Chung, Suk-Ho

2015-01-01

In a triple-port burner, various non-premixed flames have been observed previously. Especially for the case with two lifted flames, such configuration could be suitable in studying interaction between two tribrachial flames. In the present study

Life cycle assessment of opencast coal mine production: a case study in Yimin mining area in China.

Science.gov (United States)

Zhang, Li; Wang, Jinman; Feng, Yu

2018-03-01

China has the largest coal production in the world due to abundant resource requirements for economic development. In recent years, the proportion of opencast coal mine production has increased significantly in China. Opencast coal mining can lead to a large number of environmental problems, including air pollution, water pollution, and solid waste occupation. The previous studies on the environmental impacts of opencast coal mine production were focused on a single production process. Moreover, mined land reclamation was an important process in opencast coal mine production; however, it was rarely considered in previous research. Therefore, this study attempted to perform a whole environmental impact analysis including land reclamation stage using life cycle assessment (LCA) method. The Yimin opencast coal mine was selected to conduct a case study. The production of 100 tons of coal was used as the functional unit to evaluate the environmental risks in the stages of stripping, mining, transportation, processing, and reclamation. A total of six environmental impact categories, i.e., resource consumption, acidification, global warming, solid waste, eutrophication, and dust, were selected to conduct this assessment. The contribution rates of different categories of environmental impacts were significantly different, and different stages exhibited different consumption and emissions that gave rise to different environmental effects. Dust was the most serious environmental impact category, and its contribution rate was 36.81%, followed by global warming and acidification with contribution rates of 29.43% and 22.58%, respectively. Both dust and global warming were mainly affected in mining stage in Yimin opencast coal mine based on comprehensive analysis of environmental impact. Some economic and feasible measures should be used to mitigate the environmental impacts of opencast coal mine production, such as water spraying, clean transportation, increasing processing

Exhaust gas aftertreatment with online burner; Abgasnachbehandlung mit Online-Brenner

Energy Technology Data Exchange (ETDEWEB)

Rembor, Hans-Joerg; Bischler, Thomas [Huss Technologies GmbH, Nuernberg (Germany)

2010-09-15

In order to fulfil continuously tightened emission standards, modern Diesel engines for on and off road have to meet demands of catalytic exhaust gas aftertreatment with their thermomanagement. With an online burner from Huss Technologies, even with low load duty cycles, catalytic exhaust gas aftertreatment is possible. Diesel engine development can therefore be redirected again more on efficiency enhancement and other direct customer demands. (orig.)

Bench-scale testing of a micronized magnetite, fine-coal cleaning process

Energy Technology Data Exchange (ETDEWEB)

Suardini, P.J. [Custom Coals, International, Pittsburgh, PA (United States)

1995-11-01

Custom Coals, International has installed and is presently testing a 500 lb/hr. micronized-magnetite, fine-coal cleaning circuit at PETC`s Process Research Facility (PRF). The cost-shared project was awarded as part of the Coal Preparation Program`s, High Efficiency Preparation Subprogram. The project includes design, construction, testing, and decommissioning of a fully-integrated, bench-scale circuit, complete with feed coal classification to remove the minus 30 micron slimes, dense medium cycloning of the 300 by 30 micron feed coal using a nominal minus 10 micron size magnetite medium, and medium recovery using drain and rinse screens and various stages and types of magnetic separators. This paper describes the project circuit and goals, including a description of the current project status and the sources of coal and magnetite which are being tested.

Multi-ported, internally recuperated burners for direct flame impingement heating applications

Energy Technology Data Exchange (ETDEWEB)

Abbasi, Hamid A. (Naperville, IL); Kurek, Harry (Dyer, IN); Chudnovsky, Yaroslav (Skokie, IL); Lisienko, Vladimir G. (Ekaterinburg, RU); Malikov, German K. (Ekaterinburg, RU)

2010-08-03

A direct flame impingement method and apparatus employing at least one multi-ported, internally recuperated burner. The burner includes an innermost coaxial conduit having a first fluid inlet end and a first fluid outlet end, an outermost coaxial conduit disposed around the innermost coaxial conduit and having a combustion products outlet end proximate the first fluid inlet end of the innermost coaxial conduit and a combustion products inlet end proximate the first fluid outlet end of the innermost coaxial conduit, and a coaxial intermediate conduit disposed between the innermost coaxial conduit and the outermost coaxial conduit, whereby a second fluid annular region is formed between the innermost coaxial conduit and the intermediate coaxial conduit and a combustion products annular region is formed between the intermediate coaxial conduit and the outermost coaxial conduit. The intermediate coaxial conduit has a second fluid inlet end proximate the first fluid inlet end of the innermost coaxial conduit and a second fluid outlet end proximate the combustion products inlet end of the outermost coaxial conduit.

NOx emissions and potential NOx reduction for low volatile Australian coals: End-of-grant report

International Nuclear Information System (INIS)

Holcombe, D.; Nelson, P.F.; Kelly, M.D.; Gupta, R.P.; Wall, T.F.

1994-09-01

The objective of this project was to improve the understanding of NO x formation from the combustion of low-volatile Australian coals. A secondary objective was to develop NO x reduction techniques which will improve the export market potential of these coals. Low volatile coals frequently have high nitrogen levels. In addition, they differ from high volatile coals in their behaviour in the early part of the combustion process, which largely determines the level of NO x that will be formed. Low volatile coals were examined with respect to the release of nitrogen species during the early stage of PF combustion. These species are precursors to NO x and it is at this stage of combustion that furnace conditions are important in determining whether these species become NO x or are reduced to molecular nitrogen. Pilot scale measurements of NO x concentrations from the combustion of the coals were undertaken under a range of conditions to provide data on the relevance of furnace parameters as well as of coal properties. Finally, mathematical models of coal combustion with NO x formation were developed, to be able to incorporate data on nitrogen species released from coal, and to use this information as well as furnace conditions to predict NO x concentrations. (author). Tabs., figs., refs

Concentration of gallium in the Permo-Carboniferous coals of China

Energy Technology Data Exchange (ETDEWEB)

Zhao, Cunliang; Qin, Shenjun; Yang, Yinchao; Li, Yanheng; Lin, Mingyue [Hebei University of Engineering, Handan (China)

2009-10-15

Gallium is widely used in electronic industry and its current price is about 500 US dollars per kilogram. It has been found that its contents are very high in Permo-Carboniferous coal of China. In order to look for valuable associated gallium deposits in coal, gallium contents of 177 coal samples were determined by using inductively coupled plasma-mass spectrometry (ICP-MS) and the data of 873 coal samples from Chinese Permo-Carboniferous coalfields were collected. The results show that the average gallium concentration of Chinese Permo-Carboniferous coals is 15.49{mu}g{center_dot}g{sup -1}. There are two concentration types of gallium in Chinese Permo-Carboniferous coals: one type is that gallium has enriched to an ore deposit, and another type is that gallium is locally enriched in coal seams, but has not formed a valuable associated gallium ore deposit. The gallium concentration in Chinese Permo-Carboniferous coal may have several different sources: concentration in sedimentation stage, magmatic hydrothermal inputs and low-temperature hydrothermal fluids.

Environmental monitoring handbook for coal conversion facilities

Energy Technology Data Exchange (ETDEWEB)

Salk, M.S.; DeCicco, S.G. (eds.)

1978-05-01

The primary objectives of the Department of Energy's (DOE) coal conversion program are to demonstrate the environmental acceptability, technical feasibility, and economic viability of various technologies for gaseous, liquid, and solid fuels from coal. The Environmental Monitoring Handbook for Coal Conversion Facilities will help accomplish the objective of environmental acceptability by guiding the planning and execution of socioeconomic and environmental monitoring programs for demonstration facilities. These programs will provide information adequate to (1) predict, insofar as is possible, the potential impacts of construction and operation of a coal conversion plant, (2) verify the occurrence of these or any other impacts during construction and operation, (3) determine the adequacy of mitigating measures to protect the environment, (4) develop effluent source terms for process discharges, and (5) determine the effectiveness of pollution control equipment. Although useful in a variety of areas, the handbook is intended primarily for contractors who, as industrial partners with DOE, are building coal conversion plants. For the contractor it is a practical guide on (1) the methodology for developing site- and process-specific environmental monitoring programs, (2) state-of-the-art sampling and analytical techniques, and (3) impact analyses.To correspond to the phases of project activity, the subject matter is divided into four stages of monitoring: (1) a reconnaissance or synoptic survey, (2) preconstruction or baseline, (3) construction, and (4) operation, including process monitoring (prepared by Radian Corp., McLean, Va.). For each stage of monitoring, guidelines are given on socioeconomics, aquatic and terrestrial ecology, air quality and meteorology, surface and groundwater quality, geohydrology and soil survey, and surface water hydrology.

The effect of heat transfer on acoustics in burner stabilized flat flames

NARCIS (Netherlands)

Schreel, K.R.A.M.; Tillaart, van den E.L.; Janssen, R.W.M.; Goey, de L.P.H.; Koehne, H.; Lucka, K.

2003-01-01

Modern central heating systems use low NOx premixed burners with a largemodulation range. This can lead to noise problems which cannot be solved viatrial and error, but need accurate modelling. An acoustic analysis as part ofthe design phase can reduce the time-to-market considerably, but the

Measurement of O2 in the Combustion Chamber of Apulverized Coal Boiler

Directory of Open Access Journals (Sweden)

Břetislav Janeba

2012-01-01

Full Text Available Operational measurements of the O2 concentration in the combustion chamber of a pulverized coal boiler are not yet common practice. Operators are generally satisfied with measuring the O2 concentration in the second pass of the boiler, usually behind the economizer, where a flue gas sample is extracted for analysis in a classical analyzer. A disadvantage of this approach is that there is a very weak relation between the measured value and the condition in specific locations in the fireplace, e.g. the function of the individual burners and the combustion process as a whole. A new extractionline was developed for measuring the O2 concentration in the combustion chamber. A planar lambda probe is used in this approach. The extraction line is designed to get outputs that can be used directly for diagnosis or management of the combustion in the boiler.

Correction of edge-flame propagation speed in a counterflow, annular slot burner

KAUST Repository

Tran, Vu Manh

2015-10-22

To characterize the propagation modes of flames, flame propagation speed must be accurately calculated. The impact of propagating edge-flames on the flow fields of unburned gases is limited experimentally. Thus, few studies have evaluated true propagation speeds by subtracting the flow velocities of unburned gases from flame displacement speeds. Here, we present a counterflow, annular slot burner that provides an ideal one-dimensional strain rate and lengthwise zero flow velocity that allowed us to study the fundamental behaviors of edge-flames. In addition, our burner has easy optical access for detailed laser diagnostics. Flame displacement speeds were measured using a high-speed camera and related flow fields of unburned gases were visualized by particle image velocimetry. These techniques allowed us to identify significant modifications to the flow fields of unburned gases caused by thermal expansion of the propagating edges, which enabled us to calculate true flame propagation speeds that took into account the flow velocities of unburned gases.

Experiment research of slag renovation in the corner-fired boiler

Energy Technology Data Exchange (ETDEWEB)

Gong, Zhijun; Wu, Wenfei [Inner Mongolia Univ. of Science and Technology, Baotou (China). School of Energy and Environment

2013-07-01

Aiming at serious slag on the water wall around the burner of corner-fired boiler with low-ash-fusion-point coal, cold experimental model has been established. In this experiment, particle image velocimetry (PIV) has been employed to accurately measure aerodynamic field of burner region, and the experimental research of furnace slag renovation has been conducted through changing the burner jet arrangement. The experiment results show that it has significantly effect on aerodynamic field in the furnace by changing burner jet deflection angle. A reasonable actual tangential circle diameter can be formed through adjusting the burner jet deflection angle, to prevent primary air attacking the wall, and further more, to effectively prevent serious slag on the water wall around the burner.

Applying Rock Engineering Systems (RES approach to Evaluate and Classify the Coal Spontaneous Combustion Potential in Eastern Alborz Coal Mines

Directory of Open Access Journals (Sweden)

Amir Saffari

2013-12-01

Full Text Available Subject analysis of the potential of spontaneous combustion in coal layers with analytical and numerical methods has been always considered as a difficult task because of the complexity of the coal behavior and the number of factors influencing it. Empirical methods, due to accounting for certain and specific factors, have not accuracy and efficiency for all positions. The Rock Engineering Systems (RES approach as a systematic method for analyzing and classifying is proposed in engineering projects. The present study is concerned with employing the RES approach to categorize coal spontaneous combustion in coal regions. Using this approach, the interaction of parameters affecting each other in an equal scale on the coal spontaneous combustion was evaluated. The Intrinsic, geological and mining characteristics of coal seams were studied in order to identifying important parameters. Then, the main stages of implementation of the RES method i.e. interaction matrix formation, coding matrix and forming a list category were performed. Later, an index of Coal Spontaneous Combustion Potential (CSCPi was determined to format the mathematical equation. Then, the obtained data related to the intrinsic, geological and mining, and special index were calculated for each layer in the case study (Pashkalat coal region, Iran. So, the study offers a perfect and comprehensive classification of the layers. Finally, by using the event of spontaneous combustion occurred in Pashkalat coal region, an initial validation for this systematic approach in the study area was conducted, which suggested relatively good concordance in Pashkalat coal region.

Biodesulphurisation of high sulphur coal by heap leaching

Energy Technology Data Exchange (ETDEWEB)

J. Cara; M.T. Carballo; A. Moran; D. Bonilla; O. Escolano; F.J. Garcia Frutos [Universidad de Leon, Leon (Spain). Departamento de Ingenieria Quimica

2005-10-01

The biodesulphurisation of coal carried out in pile could be an interesting option to clean coal. In view of the good results obtained in biodesulphurisation test column at lab scale on a sample of semianthracite coal that proceed of an industrial plant with a high sulphur content, mainly pyritic sulphur, the feasibility of the process at pilot plant scale was studied. The pile was formed with 6 ton of gravity middlings coal sample with a grain size -12+0.5 mm from S.A. Hullera Vasco-Leonesa industrial plant. The coal has a total sulphur content of 3.78% and a pyritic sulphur content of 2.88%, the rest of sulphur is organic sulphur. The biodesulphurisation process in pilot plant follows three stages: stabilization of the pile, biodesulphurisation and washing. Heap was sampled twice during stabilisation stage, at the end of desulphurisation process and finally once washed. A pyritic sulphur removal of 39% and total sulphur removal of 23% was obtained. To complete the bioleaching process, the treatment of purge of leachate was carried out with the objective to recycling to head of process. The best treatment was a pre-treatment of the leachate until pH 4, and further treatment by reverse osmosis of the clarified water. Comparing this process with conventional precipitation to reach disposal limits, the reagents consumption and sludges were reduced considerably and due to the high quality of permeate it permits to recycle it to head of process. 18 refs., 6 figs., 6 tabs.

Effect of sulfur or hydrogen sulfide on initial stage of coal liquefaction in tetralin; Sekitan ekika shoki katei ni okeru io to ryuka suiso no hatasu yakuwari

Energy Technology Data Exchange (ETDEWEB)

Nakada, M. [Government Industrial Research Institute, Kyushu, Saga (Japan)

1996-10-28

It is well known that the solubilization of coal can be accelerated by adding sulfur or hydrogen sulfide during direct liquefaction of difficult coals. From the studies of authors on the coal liquefaction under the conditions at rather low temperatures between 300 and 400{degree}C, liquefaction products with high quality can be obtained by suppressing the aromatization of naphthene rings, but it was a problem that the reaction rate is slow. For improving this point, results obtained by changing solvents have been reported. In this study, to accelerate the liquefaction reaction, Illinois No.6 coal was liquefied in tetralin at temperature range from 300 to 400{degree}C by adding a given amount of sulfur or hydrogen sulfide at the initial stage of liquefaction. The addition of sulfur or hydrogen sulfide provided an acceleration effect of liquefaction reaction at temperature range between 300 and 400{degree}C. The addition of sulfur or hydrogen sulfide at 400{degree}C increased the oil products. At 370 and 400{degree}C, the liquid yield by adding sulfur was slightly higher than that by adding hydrogen sulfide, unexpectedly. The effects of sulfur and hydrogen sulfide were reversed when increasing the hydrogen pressure. 5 figs., 1 tab.

Computational fluid dynamics (CFD) modelling of coal/biomass co-firing in pulverised fuel boilers

Energy Technology Data Exchange (ETDEWEB)

Moghtaderi, B.; Meesri, C. [University of Newcastle, Callaghan, NSW (Australia). CRC for Coal in Sustainable Development, Dept. of Chemical Engineering

2002-07-01

The present study is concerned with computational fluid dynamics (CFD) modelling of coal/biomass blends co-fired under conditions pertinent to pulverised fuel (PF) boilers. The attention is particularly focused on the near burner zone to examine the impact of biomass on the flame geometry and temperature. The predictions are obtained by numerical solution of the conservation equations for the gas and particle phases. The gas phase is solved in the Eulerian domain using steady-state time-averaged Navier-Stokes equations while the solution of the particle phase is obtained from a series of Lagrangian particle tracking equations. Turbulence is modelled using the {kappa}-{epsilon} and Reynolds Stress models. The comparison between the predictions and experimental measurement reported in the literature resulted in a good agreement. Other influences of biomass co-firing are observed for fuel devolatilisation and burnout. 19 refs., 6 figs.

Study on Transfer Rules of Coal Reservoir Pressure Drop Based on Coalbed Methane Well Drainage Experiments

Science.gov (United States)

Yuhang, X.

2017-12-01

A pumping test was carried out to explore the transfer rules of pressure drop in coal reservoir during the drainage. The experiment was divided into three stages. In the first stage, the pump displacement of 3m3/h was used to reduce the bottom hole flowing pressure and stopped until the continuous gas phase was produced; Undertaking the first stage, in the second stage, when the gas phase was continuously produced, the pump was stopped immediately. As the bottom hole flowing pressure going up without gas phase, pumping started again for a week. In the third stage ,the well pumping was carried out at the bottom hole pressure drop rate of 30Kpa/d after two months' recovery. Combined with the data of regional geology and fractured well, taking the characteristics of macroscopic coal rocks, development of pore and fracture in coal and isothermal adsorption test as the background, the features of reservoir output in each stage of the experiment were analyzed and compared, and then the transfer rules of pressure drop contained in the differences of the output was studied further. In the first and third stage of the experiment, the output of liquid phase was much larger than the space volume of coal reservoir pore and fracture in the range of 100m2. In the second stage, the output of the continuous gas phase appeared around 0.7Mpa when the continuous gas phase appears below the critical desorption pressure of 0.25Mpa during the whole experiment. The results indicate that, the transfer of pressure drop in the coal reservoir of this well is mainly horizontal, and the liquid phase produced in the reservoir mainly comes from the recharge of the reservoir at the far end of the relative high pressure area; the adsorption space of coalbed methane in the coal matrix as well as the main migration channel of fluid in the reservoir doesn't belong to the same pressure system and there exists the communication barrier between them. In addition, the increasing of the effective stress

The effect of heat transfer on acoustics in burner stabilized flat flames