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Thermal Expansion of Solids and Liquids

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I NTERNATIONAL J OURNAL OF E NERGY AND E NVIRONMENT Volume 4, Issue 2, 2013 pp.191-198 Journal homepage: www.IJEE.IEEFoundation.org ISSN 2076-2895 (Print), ISSN 2076-2909 (Online) ©2013 International Energy & Environment Foundation. All rights reserved. An experimental study on the thermal valorization of municipal and animal wastes Despina Vamvuka 1 , Stelios Sfakiotakis 1 , Kyriakos D. Panopoulos 2 1 Department of Mineral Resources Engineering, Technical University of Crete, Crete, Greece. 2 Centre for Research & Technology Hellas / Institute for Solid Fuels Technology & Applications (CERTH/ISFTA), 4 th klm. Nat. Rd. Ptolemais-Kozani-P.O. box 95 – GR 50200 Ptolemais, Greece. Abstract Poultry wastes and refused derived fuel disposal through thermochemical processes, such as combustion, has been proposed. These fuels have calorific values that in many cases exceed 20MJ kg -1 . An extensive analysis has been performed of pyrolysis and combustion results obtained by thermal analysis measurements. The weight loss data were recorded continuously, under dynamic conditions, in the range 25-1300ºC. A first order parallel reactions model and a power low model fitted the experimental results accurately for pyrolysis and combustion, respectively. The pyrolysis of poultry waste was a complex process, occurring up to 1300°C with high activation energies. Copyright © 2013 International Energy and Environment Foundation - All rights reserved. Keywords: Poultry wastes; RDF; Pyrolysis; Combustion. 1. Introduction Given the trend to replace fossil carbon and gain additional revenue, the power generation sector across the world is considering the use of secondary fuels, such as animal breeding and household wastes. As landfill disposal is no longer a viable solution, due to the high cost and the environmental regulations, thermal treatment of these wastes is an attractive option, by destroying hazardous constituents, reducing their volume, allowing for energy recovery and increasing economic returns to rural communities. Chicken eggs and meat is one the most widely used protein source throughout the world. Nowadays, it is more and more common to have large scale chicken industries. There is about 50g of wastes generated by a chick every day and this mainly composes of: manure, bedding material, waste feed, dead birds, broken eggs and feathers. Refused derived fuel (RDF) is produced from municipal solid wastes (MSW) through a procedures comprising source-separated, processed and dried combustible MSW fraction. It consists of mostly cellulosic and plastic components. Several thermal systems have been proposed for poultry litter and RDF valorization for energy. Fast pyrolysis of poultry wastes (PW) has been tried out but the results were not so promising, as the bio-oil yield of poultry litter was relatively low compared to wood derived bio-oil (34–42wt%) [1]. Pyrolysis of RDF is crucial in thermochemical conversion processes, due to the high volatile content of this fuel. Volatile species evolved have been characterized by TGA-FTIR and TGA-MS techniques [2]. Combustion of PW and RDF has been accomplished in fluidized bed combustion units [3, 4]. Care should be given in both direct combustion and co-combustion on the effect of chlorine and nitrogen, International Journal of Energy and Environment (IJEE), Volume 4, Issue 2, 2013, pp.191-198 ISSN 2076-2895 (Print), ISSN 2076-2909 ...http://72.3.142.35/mghdxreader/jsp/print/FinalDisplayForPrint.jsp;jses 1 de 1 24/4/2006 10:00 The Properties of Gases and Liquids, Fifth Edition Bruce E. Poling, John M. Prausnitz, John P. O’Connell cover Printed from Digital Engineering Library @ McGraw-Hill (www.Digitalengineeringlibrary.com). Copyright ©2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. >> 1.1 CHAPTER ONE THE ESTIMATION OF PHYSICAL PROPERTIES 1-1 INTRODUCTION The structural engineer cannot design a bridge without knowing the properties of steel and concrete. Similarly, scientists and engineers often require the properties of gases and liquids. The chemical or process engineer, in particular, finds knowl- edge of physical properties of fluids essential to the design of many kinds of prod- ucts, processes, and industrial equipment. Even the theoretical physicist must oc- casionally compare theory with measured properties. The physical properties of every substance depend directly on the nature of the molecules of the substance. Therefore, the ultimate generalization of physical prop- erties of fluids will require a complete understanding of molecular behavior, which we do not yet have. Though its origins are ancient, the molecular theory was not generally accepted until about the beginning of the nineteenth century, and even then there were setbacks until experimental evidence vindicated the theory early in the twentieth century. Many pieces of the puzzle of molecular behavior have now fallen into place and computer simulation can now describe more and more complex systems, but as yet it has not been possible to develop a complete generalization. In the nineteenth century, the observations of Charles and Gay-Lussac were combined with Avogadro’s hypothesis to form the gas ‘‘law,’’ PV ϭ NRT, which was perhaps the first important correlation of properties. Deviations from the ideal- gas law, though often small, were finally tied to the fundamental nature of the molecules. The equation of van der Waals, the virial equation, and other equations of state express these quantitatively. Such extensions of the ideal-gas law have not only facilitated progress in the development of a molecular theory but, more im- portant for our purposes here, have provided a framework for correlating physical properties of fluids. The original ‘‘hard-sphere’’ kinetic theory of gases was a significant contribution to progress in understanding the statistical behavior of a system containing a large number of molecules. Thermodynamic and transport properties were related quan- titatively to molecular size and speed. Deviations from the hard-sphere kinetic the- ory led to studies of the interactions of molecules based on the realization that molecules attract at intermediate separations and repel when they come very close. The semiempirical potential functions of Lennard-Jones and others describe attrac- tion and repulsion in approximately quantitative fashion. More recent potential functions allow for the shapes of molecules and for asymmetric charge distribution in polar molecules. Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as [...]... the properties of gases and liquids The chemical or process engineer, in particular, finds knowledge of physical properties of fluids essential to the design of many kinds of products, processes, and industrial equipment Even the theoretical physicist must occasionally compare theory with measured properties The physical properties of every substance depend directly on the nature of the molecules of the... point and the chemical formula Most estimation methods require parameters that are characteristic of single pure components or of constituents of a mixture of interest The more important of these are considered in Chap 2 The thermodynamic properties of ideal gases, such as enthalpies and Gibbs energies of formation and heat capacities, are covered in Chap 3 Chapter 4 describes the PVT properties of pure... equations of state, and methods restricted to liquids Chapter 5 extends the methods of Chap 4 to mixtures with the introduction of mixing and combining rules as well as the special effects of interactions between different components Chapter 6 covers other thermodynamic properties such as enthalpy, entropy, free energies and heat capacities of real fluids from equations of state and correlations for liquids. .. practice of physical properties data’’ (Dewan and Moore, 1999) where searching the World Wide Web can retrieve property information from sources and at rates unheard of a few years ago Yet despite the many handbooks and journals devoted to compilation and critical review of physical-property data, it is inconceivable that all desired experimental data will ever be available for the thousands of compounds of. .. members of the pair having [ϭ] or [ϵ]; if they both have a ϭ or a ϵ without the brackets [ ], they will also have at least 1 — and the bonding of the pair is via a single bond Therefore, the substance CHFϭCFCF3 would have 1 pair of [ϭ]CH — & [ϭ]CϽ, 1 pair of ϭCH — & F — , 1 pair of ϭCϽ & — F, 1 pair of ϭCϽ and ϾCϽ, and 3 pairs of ϾCϽ & — F The location of bonding in esters is distinguished by the use of. .. establishing and collecting estimation methods for physical properties of fluids as required for chemical process and product design B E Poling J M Prausnitz J P O’Connell This page intentionally left blank CHAPTER ONE THE ESTIMATION OF PHYSICAL PROPERTIES 1-1 INTRODUCTION The structural engineer cannot design a bridge without knowing the properties of steel and concrete Similarly, scientists and engineers often... is, temperature and density The correlation of a and b in terms of other properties of a substance is an example of Series in Thermal & Fluid Physics & Engineering Editor: G.F. Hewitt Practical Thermal Design of Shell-and-Tube Heat Exchangers R. 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ROWLAND •* ABSTRACT Differential thermal analysis (DTA) began soon after the de- velopment of the thermocouple. It has progressed through the systematic development of better equipment and the cataloguing of typical DTA curves for a variety of materials until good technique now requires control of the composition and pressure of the furnace atmosphere as well as consideration of the thermo- dynamics and kinetics of the reactions involved. Although dif- ferential thermal analyses have been made for many materials, the major applications have been concerned with clay and car- bonate minerals. In DTA curves for clay minerals the low-temperature endo- thermic loop associated with the loss of water, and the high- temperature exothermic loop accompanying the formation of new compounds, are changed in shape, temperature, and intensity by the kind of exchange cations. The midtemperature-range endo- thermic loop has a temperature dependence on the partial pres- sure of water in the furnace atmosphere. For the anhydrous normal carbonates the dissociation tempera- ture and its dependence on the partial pressvire of CO2 are in the decreasing order Ca, Mg, Mn, Fe, and Zn. The lower temperature loop of dolomite, the reaction for which must be preceded by an internal rearrangement, is independent of the pressure of ('()•• but may be shifted to a lower temperature by prolonged fine grinding which accomplishes a similar rearrangement. INTRODUCTION Differential thermal analysis (DTA), although not a very accurate or definitive method, has found an impor- tant place amon» techniques which allow the characteri- zation of materials. Limited only by the sensitivity of the apparatus, the differential thermal curves record all transformations in which heat is taken up or given off. This includes the dehydration of clays, the decarbona- tion of carbonates, the reversible change from a- to |3-quartz, the burning of materials, and the recombina- tion of elements into more stable forms. When employed alone, the technique can be used to identify a number of reasonably pure compounds and to follow changes in mixtures for control purposes. When used in eonjunc- with X-ray diffraction, microscopy, and chemical analy- sis, otherwise difficult identifications can be made. The technique is not easily standardized, however, and the factors which frequently make it difficult to compare DTA curves prepared in different laboratories are sum- marized by Ahrens (1950). The development of differential thermal analysis has progressed through several stages. As early as 1887 le Chatelier described the use of his thermocouple as a difference thermocouple and published DTA curves of kaolinite. Prom that time until Orcel (1935) began the systematic differential thermal analyses of clays, about twenty miscellaneous DTA papers appeared. Another stage began with the design of good furnaces, ssimple holders, and photographic recording equipment by Norton (1939) and Hendricks (1939). Refinements of this design by Grim and Rowland (1942) were followed by further developments by Berkelhamer and Spiel (1944). Throughout this period many papers appeared which repeated .. .Thermal Expansion of Solids and Liquids • Linear thermal expansion is ΔL = αLΔT, where ΔL is the change in length L, ΔT is the change in temperature, and α is the coefficient of linear expansion, ... –10.0ºC? Although the monument is made of limestone, assume that its thermal coefficient of expansion is the same as marble’s 11/14 Thermal Expansion of Solids and Liquids 169.98 m How much taller... linear expansion, is less susceptible Water expands significantly when it freezes: a volume increase of about 9% occurs As a result of this expansion and because of the formation and growth of crystals

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