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The Handbook of Biomass Combustion and Co-firing

The Handbook of Biomass Combustion and Co-firing
A Book

by Sjaak Van Loo,Jaap Koppejan

  • Publisher : Earthscan
  • Release : 2012-05-16
  • Pages : 464
  • ISBN : 1849773041
  • Language : En, Es, Fr & De
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This unique handbook presents both the theory and application of biomass combustion and co-firing, from basic principles to industrial combustion and environmental impact, in a clear and comprehensive manner. It offers a solid grounding on biomass combustion, and advice on improving combustion systems.Written by leading international academics and industrial experts, and prepared under the auspices of the IEA Bioenergy Implementing Agreement, the handbook is an essential resource for anyone interested in biomass combustion and co-firing technologies varying from domestic woodstoves to utility-scale power generation. The book covers subjects including biomass fuel pre-treatment and logistics, modelling the combustion process and ash-related issues, as well as featuring an overview of the current R&D needs regarding biomass combustion.

Biomass combustion science, technology and engineering

Biomass combustion science, technology and engineering
5. Biomass co-firing

by C. Yin

  • Publisher : Elsevier Inc. Chapters
  • Release : 2013-04-04
  • Pages : 320
  • ISBN : 0128087579
  • Language : En, Es, Fr & De
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Co-firing biomass with fossil fuels in existing power plants is an attractive option for significantly increasing renewable energy resource utilization and reducing CO2 emissions. This chapter mainly discusses three direct co-firing technologies: pulverized-fuel (PF) boilers, fluidized-bed combustion (FBC) systems, and grate-firing systems, which are employed in about 50%, 40%, and 10% of all the co-firing plants, respectively. Their basic principles, process technologies, advantages, and limitations are presented, followed by a brief comparison of these technologies when applied to biomass co-firing. This chapter also briefly introduces indirect co-firing and parallel co-firing and their application status.

Handbook of Biomass Combustion and Co-firing

Handbook of Biomass Combustion and Co-firing
A Book

by Sjaak van Loo,Jaap Koppejan,Task of the Implementing Agreement on Bioenergy International Energy Agency

  • Publisher : Unknown Publisher
  • Release : 2002
  • Pages : 348
  • ISBN : 9789036517737
  • Language : En, Es, Fr & De
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Energy Ans Exergy Analysis of Biomass Co-firing in Pulverized Coal Power Generation

Energy Ans Exergy Analysis of Biomass Co-firing in Pulverized Coal Power Generation
A Book

by Shoaib Mehmood,University of Ontario Institute of Technology

  • Publisher : Unknown Publisher
  • Release : 2011
  • Pages : 329
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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Biomass co-firing with coal exhibits great potential for large scale utilization of biomass energy in the near future. In the present work, energy and exergy analyses are carried out for a co-firing based power generation system to investigate the impacts of biomass cofiring on system performance and gaseous emissions of CO2, NOx, and SOx. The power generation system considered is a typical pulverized coal-fired steam cycle system, while four biomass fuels (rice husk, pine sawdust, chicken litter, and refuse derived fuel) and two coals (bituminous coal and lignite) are chosen for the analysis. System performance is evaluated in terms of important performance parameters for different combinations of fuel at different co-firing conditions and for the two cases considered. The results indicate that plant energy and exergy efficiencies decrease with increase of biomass proportion in the fuel mixture. The extent of decrease in energy and exergy efficiencies depends on specific properties of the chosen biomass types. The results also show that the increased fraction of biomass significantly reduces the net CO2 emissions for all types of selected biomass. However, gross CO2 emissions increase for all blends except bituminous coal/refuse derived fuel blend, lignite/chicken litter blend and lignite/refuse derived fuel blend. The reduction in NOx emissions depends on the nitrogen content of the biomass fuel. Likewise, the decrease in SOx emissions depends on the sulphur content of the biomass fuel. The most appropriate biomass in terms of NOx and SOx reduction is sawdust because of its negligible nitrogen and sulphur contents.

Closed-loop Biomass Co-firing in a Laboratory Reactor and in a Full-scale Boiler

Closed-loop Biomass Co-firing in a Laboratory Reactor and in a Full-scale Boiler
A Book

by Robert B. Williams,Bryan M. Jenkins,Lee A. Jakeway,Scott Q. Turn,Linda Gail Blevins

  • Publisher : Unknown Publisher
  • Release : 2004
  • Pages : 58
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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Co-firing tests were conducted in a pilot-scale reactor at Sandia National Laboratories and in a boiler at the Hawaiian Commercial & Sugar factory at Puunene, Hawaii. Combustion tests were performed in the Sandia Multi-Fuel Combustor using Australian coal, whole fiber cane including tops and leaves processed at three different levels (milled only, milled and leached, and milled followed by leaching and subsequent milling), and fiber cane stripped of its tops and leaves and heavily processed through subsequent milling, leaching, and milling cycles. Testing was performed for pure fuels and for biomass co-firing with the coal at levels of 30% and 70% by mass. The laboratory tests revealed the following information: (1) The biomass fuels convert their native nitrogen into NO more efficiently than coal because of higher volatile content and more reactive nitrogen complexes. (2) Adding coal to whole fiber cane to reduce its tendency to form deposits should not adversely affect NO emissions. (3) Stripped cane does not offer a NO advantage over whole cane when co-fired with coal. During the field test, Sandia measured 0 2, C02, CO, SO2, and NO concentrations in the stack and gas velocities near the superheater. Gas concentrations and velocities fluctuated more during biomass co-firing than during coal combustion. The mean 0 2 concentration was lower and the mean C02 concentration was higher during biomass co-firing than during coal combustion. When normalized to a constant exhaust 0 2 concentration, mean CO concentration was higher and mean NO concentration was lower for biomass co-firing than for coal. The SO2 concentration tracked the use of Bunker C fuel oil. When normalized by the amount of boiler energy input, the amounts of NO and SO2 formed were lower during biomass co-firing than during coal combustion. The difference between NOx trends in the lab and in the field are most likely a result of less effective heat and mass transfer in the boiler. Particles were sampled near the superheater tube using an impaction probe and were analyzed using scanning electron microscopy. Particle loading appeared higher for biomass co-firing than for coal combustion, especially for the smaller particle diameters. Laser-induced breakdown spectroscopy (LIBS) was used to detect silicon, aluminum, titanium, iron, calcium, magnesium, sodium, and potassium concentrations near the superheater. LIBS provided an abundant amount of real-time information. The major constituents of the fuel ash (silicon and aluminum) were also the major measured inorganic constituents of the combustion products. The combustion products were enriched in sodium relative to the fuel ash during all tests, and they were enriched in potassium for the biomass co-firing tests. Alkali metals are enriched because compounds containing these elements are more readily releasable into the combustion products than refractory components that remain in large particles such as silicon, aluminum, and titanium. Relative to the measured deposit chemistry, the combustion flows were enriched in iron, sodium, and potassium, constituents that are known to form fumes laden with fine particles and/or vapors. The LIBS results yield insight into the deposition mechanism: Impaction of larger particles dominates over fume deposition. The present application of LIBS reveals its potential to provide real-time field information on the deposition propensity of different fuels and the effects of different fuels and boiler operating conditions.

Biomass Co-firing with Coal and Natural Gas

Biomass Co-firing with Coal and Natural Gas
A Book

by Ezinwa Uchechukwu Agbor

  • Publisher : Unknown Publisher
  • Release : 2015
  • Pages : 119
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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Biomass fuels have long been accepted as useful renewable energy sources, especially in mitigating greenhouse gases (GHG) emissions. Fossil fuel-based power plants make up over 30% of the GHG emissions in Alberta, Canada. Displacement of fossil fuel-based power through biomass co-firing has been proposed as a near-term option to reduce these emissions. In this research, co-firing of three biomass feedstocks (i.e., whole forest, agricultural residues and forest residues) at varying proportions with coal as well as with natural gas in existing plants was studied to investigate different co-firing technologies. Whole forest biomass refers to live or dead trees (spruce and mixed hardwood) not considered merchantable for pulp and timber production; agricultural residues are straws obtained as the by-product of threshing crops such as wheat, barley, and flax; and forest residues refer to the limbs and tops of the trees left on the roadside to rot after logging operations by pulp and timber companies. Data-intensive models were developed to carry out detailed techno-economic and environmental assessments to comparatively evaluate sixty co-firing scenarios involving different levels of the biomass feedstock co-fired with coal in existing 500 MW subcritical pulverized coal (PC) plants and with natural gas in existing 500 MW natural gas combined cycle (NGCC) plants. Minimum electricity production costs were determined for the co-fired plants for the same three biomass feedstocks and base fuels. Environmental assessments, from the point of harvesting to delivering electricity to the customers, was evaluated and compared to the various co-fired configurations to determine the most economically viable and environmental friendly options of biomass co-firing configuration for western Canada. The results obtained from these analyses shows that the fully paid-off coal-fired power plant co-fired with forest residues is the most attractive option and has levelized cost of electricity (LCOE) ranging from $53.12 to $54.50/MWh; and CO2 abatement costs ranging from $27.41 to $31.15/tCO2. Similarly, the LCOE and CO2 abatement costs for whole forest chips range from $54.68 to $56.41/MWh and $35.60 to $41.78/tCO2 respectively. When straw is co-fired with coal in a fully paid-off plant, the LCOE and CO2 abatement costs range from $54.62 to $57.35/MWh and $35.07 to $38.48/tCO2 respectively. This is of high interest considering the likely increase of the carbon levy to about $30/tCO2 in the Province of Alberta by 2017.

Co-firing of Biomass at UK Power Plant

Co-firing of Biomass at UK Power Plant
A Book

by Anonim

  • Publisher : Unknown Publisher
  • Release : 2005
  • Pages : 36
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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Biomass Combustion and Co-firing

Biomass Combustion and Co-firing
An Overview

by International Energy Agency, 75 - Paris (FR).

  • Publisher : Unknown Publisher
  • Release : 2002
  • Pages : 14
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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Co-firing biomass with coal-power plant case study

Co-firing biomass with coal-power plant case study
A Book

by K. C. G. Bindemann,H. J. Graham

  • Publisher : Unknown Publisher
  • Release : 1997
  • Pages : 329
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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Evaluation of drying processes for biomass co-firing in coal fired steam power plants

Evaluation of drying processes for biomass co-firing in coal fired steam power plants
A Book

by Birte Everts

  • Publisher : Cuvillier Verlag
  • Release : 2016-12-30
  • Pages : 136
  • ISBN : 3736984413
  • Language : En, Es, Fr & De
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In dieser Arbeit werden verschiedene Prozesse zu Biomassetrocknung für die anschließende Mitverbrennung in kohlebefeuerten Dampfkraftwerken untersucht. Modelle der verschiedenen Trocknungsprozesse, sowie Modelle des Dampferzeugers und des Gesamtprozesses werden erstellt, um die Auswirkungen der Biomassemitverbrennung auf den Kraftwerksprozess zu untersuchen. Mehrere Szenarien für die dezentrale und prozessintegrierte Trocknung werden analysiert und bewertet. In this work, several processes for biomass drying for biomass co firing in coal fired steam power plants are evaluated. Models are developed for each drying process, as well as for the power plant boiler and the overall power generation process, to analyse the consequences and impacts of biomass co firing on the power generation process. Several scenarios for decentralised and process integrated drying are analysed and evaluated.

EOS-LT Consortium Biomass Co-firing

EOS-LT Consortium Biomass Co-firing
WP 4 - Biomass Co-firing in Oxy-fuel Combustion : Part I: Lab-scale Experiments

by L. Fryda

  • Publisher : Unknown Publisher
  • Release : 2010
  • Pages : 58
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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Investigation of Ash Deposition During Co-firing Biomass/peat with Coal in a Pilot-scale Fluidized-bed Reactor

Investigation of Ash Deposition During Co-firing Biomass/peat with Coal in a Pilot-scale Fluidized-bed Reactor
A Book

by Yuanyuan Shao

  • Publisher : Unknown Publisher
  • Release : 2011
  • Pages : 329
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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Biomass, a promising alternative to fossil fuels, has been applied widely for energy generation by co-firing technology in recent year particularly in the EU countries. In this thesis, a key issue of biomass co-firing technology - ash deposition in combustion, co-combustion and gasification, was comprehensively investigated in a pilot-scale bubbling fluidized bed reactor. A custom-designed, air-cooled probe was installed in the freeboard zone of the reactor to simulate the heat-transfer surface and collect ash deposits from the process. A local lignite coal, a woody biomass (white pine), and a Canadian peat were involved in the tests. The main varying operating parameters investigated in this study included: blending ratio, air/fuel ratio, moisture content and sulphur addition for the combustion/combustion tests; equivalence ratio, bed materials and fuel types for the gasification tests. A new parameter, "relative deposition rate" (RDA) was proposed in this study to evaluate the relative deposition tendencies of biomass fuels and biomass-coal mixed fuels against the coal as the base fuel for co-firing. As expected, co-firing of the lignite and the wood pellets (with a much lower ash-content than the lignite) resulted in a decreased superficial rate of ash deposition. However, co-firing of woody biomass and lignite coal did not significantly increase the ash deposition tendency in terms of the values of RDA, and more interestingly, co-firing of the fuel blend of 50% lignite-50% white pine pellets produced a lower RDA. Co-combustion of three-fuel blend at 20%lignite-40%peat-40%pine resulted in the lowest deposition rate and the least deposition tendency among all the combustion tests with various mixed fuels or individual fuels. Another new and interesting discovery of this study was that fluidized-bed combustion of an individual fuel or a fuel blend with a higher moisture content produced not only a more uniform temperature profile along the fluidized-bed column but also a reduced ash deposition rate. A higher chlorine concentration in the feed would generally result in a higher tendency of ash deposition. Adding sulfur into the fuel of coal or peat could effectively decrease the chloride deposition in the ash deposits via sulphation. The sulphur addition could also reduce the ash deposition rate for the combustion of lignite, while it slightly increased the ash deposition rate for the peat fuel. In air-blown gasification of a woody biomass and a Canadian peat, the experimental results demonstrated that among the four bed materials (olivine, limestone, iron ore, and dolomite), the use of olivine resulted in the lowest ash deposition rate. The superb performance of olivine in retarding ash deposition could be accounted for by its outstanding thermal stability and mechanical strength. The other three bed materials, in particular limestone, were fragile during the fluidized bed gasification, and the fractured fines from the bed materials were found to deposit along with the fuel-ash on the heat transfer surface, leading to higher ash deposition rates. Finally, mathematical models parameterized with interactions between fuel chlorine, alkali and ash particles were developed to analyze the ash and chlorine deposition behavior based on the experimental data from co-firing peat with lignite coal. The developed equations in this study can not only describe the dependence of the deposition rate and the ash chlorine content on the fraction of peat, but can also determine suitable range of the peat fraction for smooth operations, which would be useful for co-firing other fuel blends.

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

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

by Anonim

  • Publisher : Unknown Publisher
  • Release : 2002
  • Pages : 79
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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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(subscript x) pollutant emissions produced will be similar to or lower than pollutant emissions when firing coal. This is a surprising result as the levels of N are higher in the biomass fuel than in coal. Further experiments showed that biomass is twice or more effective than coal when used in a reburning process to reduce NO(subscript x) emissions. Since crushing costs of biomass fuels may be prohibitive, stoker firing may be cost effective; in order simulate such a firing, future work will investigate the performance of a gasifier when fired with larger sized coal and biomass. It will be a fixed bed gasifier, and will evaluate blends, coal, and biomass. Computer simulations were performed using the PCGC-2 code supplied by BYU and modified by A & M with three mixture fractions for handling animal based biomass fuels in order to include an improved moisture model for handling wet fuels and phosphorus oxidation. Finally the results of the economic analysis show that considerable savings can be achieved with the use of biomass. In the case of higher ash and moisture biomass, the fuel cost savings will be reduced, due to increased transportation costs. A spreadsheet program was created to analyze the fuel savings for a variety of different moisture levels, ash levels, and power plant operating parameters.

ENDOGENOUS ADOPTION DECISIONS OF COAL-BIOMASS CO-FIRING

ENDOGENOUS ADOPTION DECISIONS OF COAL-BIOMASS CO-FIRING
AN EQUILIBRIUM FRAMEWORK APPROACH.

by Brayam Valqui Ordonez

  • Publisher : Unknown Publisher
  • Release : 2018
  • Pages : 329
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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Biomass co-firing technology with coal is an alternative means to achieving Renewable Portfolio Standards (RPS) that could also extend the life of coal-fired power plants. This approach is particularly attractive in regions where there is a considerable potential supply of biomass and where a high share of electricity generation capacity comes from coal plants. An RPS that allows for biomass co-firing could provide an incentive for some plants that otherwise would not co-fire. In order to properly assess the likely response of coal units in a region requires taking into consideration competition among coal plants and other generation sources. Further, such an analysis would require estimating biomass local availability, which is heterogeneous across different areas, and could drive up its price, making co-firing not economic feasible for some plants. In this thesis, I present a holistic framework allowing for endogenous adoption decisions of whether a plant chooses to co-fire or not. This framework is composed of a detailed power system that determines hourly output at each power plant while accounting for real world operational constraints (Unit Commitment Model) and a game-theoretic model that solves for a stable equilibrium among power plants competing for biomass. As a case study, I apply this framework to the Midcontinent Independent System Operator (MISO), where many states have an existing RPS and where there is a high potential to obtain corn residue as a biomass. I simulate a co-firing rate under a broad range of carbon prices, which act as a RPS that includes biomass, and numerically solve for the Nash Equilibrium; i.e., none of the competing coal plants would unilaterally change their decisions whether to co-fire with biomass.

CO-FIRING COAL

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

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

  • Publisher : Unknown Publisher
  • Release : 2003
  • Pages : 256
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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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 used in a reburning process. Computer simulations for coal: LB blends were performed by modifying an existing computer code to include the drying and phosphorus (P) oxidation models. The gasification studies revealed that there is bed agglomeration in the case of chicken litter biomass due to its higher alkaline oxide content in the ash. Finally, the results of the economic analysis show that considerable fuel cost savings can be achieved with the use of biomass. In the case of higher ash and moisture biomass, the fuel cost savings is reduced.

Closed Loop Biomass Co-Firing

Closed Loop Biomass Co-Firing
A Book

by Anonim

  • Publisher : Unknown Publisher
  • Release : 2000
  • Pages : 5
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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Development and Application of a Decision Support Tool for Biomass Co-firing in Existing Coal Fired Power Plants

Development and Application of a Decision Support Tool for Biomass Co-firing in Existing Coal Fired Power Plants
A Book

by Jason S. Smith

  • Publisher : Unknown Publisher
  • Release : 2015
  • Pages : 126
  • ISBN : 9781339045979
  • Language : En, Es, Fr & De
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Biomass Co-firing

Biomass Co-firing
A Renewable Alternative for Utilities

by Anonim

  • Publisher : Unknown Publisher
  • Release : 2000
  • Pages : 5
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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Biomass is a proven option for electricity generation. A diverse range of biopower producers includes electric utilities, independent power producers, and the pulp and paper industry. To help expand opportunities for biomass power production, the U.S. Department of Energy established the Biopower Program and is sponsoring efforts to increase the productivity of dedicated energy crops. The Program aims to double biomass conversion efficiencies, thus reducing biomass power generation costs. These efforts will promote industrial and agricultural growth, improve the environment, create jobs, increase U.S. energy security, and provide new export markets.

Co-firing Fossil Fuels and Biomass

Co-firing Fossil Fuels and Biomass
Combustion, Deposition and Modelling

by Ala H. M. Khodier

  • Publisher : Unknown Publisher
  • Release : 2011
  • Pages : 329
  • ISBN : 9876543210XXX
  • Language : En, Es, Fr & De
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The application of advanced technologies employing combustion/co-firing of coal andbiomass is seen as a promising approach to minimising the environmental impact andreducing CO2 emissions of heat/power production. The existing uncertainties in thecombustion behaviour of such fuel mixes and the release of alkali metals with otherelements during the combustion (or co-firing) of many bio-fuels are some of the mainissues that are hindering its application. The potential presence of high levels of alkalichlorides and low levels of sulfates in the deposits formed on heat exchanger can causeenhanced corrosion and/or limit the heat transfer between the hot combustion gases andthe water/steam system within the process plant. This work has investigated the detailed gas compositions and deposition characteristicsof the combusted gas streams produced from fossil and biomass fuels pure and/or blendin a pilot-scale combustors (PF and FBC) at Cranfield University. Combustion gasanalysis were obtained on-line by a high resolution multi-component Fourier TransformInfra-Red (FTIR) gas analyser and deposits samples were collected from the flue gasusing air-cooled probes with surface temperatures of about 500, 600, 700oC andanalysed using SEM-EDX and XRD techniques. Fuels included several biomass fuels(cereal co-product (CCP) straw, miscanthus (pulverised), oil seed rape straw (againststored pellets), miscanthus (pellets), willow, fast pyrolysis bio-oil) and twocommercially-used coals (El-cerrejon and Daw Mill). The results of the experimentalstudies have been compared with thermodynamic equilibrium predictions. High combustion efficiency was maintained throughout the range of fuel mixes. TheSO2 and HCl levels were low in pure biomass combustion and increased as the biomassfraction of the fuel decreased when co-fired with these coals. However, the NOx outputremained stable except for Miscanthus:Daw Mill mixtures and OSR stored pelletcombustion. The deposition flux was highest on the coolest probes for each fuel. Thelowest deposition fluxes were found for the combustion of either fast pyrolysis bio-oilor coppiced willow. There is evidence of significant differences deposition fluxesbetween El-cerrejon coal and Daw Mill coal mixed with CCP and/or miscanthus. Thepresence of chlorine was identified in deposits produced from combustion of purebiomass or high biomass mixes. The lowest levels found here in fast pyrolysis bio-oilcombustion and only detected at higher shares (? 80 %) of biomass co-fired with DawMill coal, whereas, mixed biomass with El-cerrejon coal produced Cl in deposits at alow % biomass share. The application of thermodynamic equilibrium modelling has been found to be usefultool for providing a qualitative understanding of elements present and/or control by hotgas in modern combustion processes.

Assessment of Situation and Potential for Co-Firing Coal and Biomass in Energy Facilities

Assessment of Situation and Potential for Co-Firing Coal and Biomass in Energy Facilities
A Book

by DIANE Publishing Company

  • Publisher : Unknown Publisher
  • Release : 1994-03-01
  • Pages : 96
  • ISBN : 9780788106156
  • Language : En, Es, Fr & De
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Reviews the status & potential for co-firing of biomass with coal in the Great Lakes region. The assessment is based on literature review, extensive interviewing, & detailed case studies of facilities that are now or a capable of co-firing. Addresses the economic & technological impacts of co-firing, the effects of co-firing on air emissions, & includes 9 case studies, as well as information on equipment, fuel sources & system performance. Tables & charts.