Methods and Tools and Optimization of for Analysis Power Plants

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Methods and Tools and Optimization of for Analysis Power Plants Methods and Tools For Analysis and Optimization of Power Plants ,.. ;.., Mohsen Assadi Division of Power Plant Technology Department of Heat and Power Engineering Lund Institute of Technology Doctoral Thesis Methods and Tools for Analysis and !., , .: .,.... ,,, , Optimization of Power Plants L:, .,,,,, ,,y~.,,, .: ::, + ,. Av Mohsen Assadi , ,. ,, :,, ,,. ,,, c., , Akademisk avhandling ,, som for avlaggande av teknisk doktorsexamen vid tekniska fidculteten vid Lunds Universitet kommer att firsvaras vid offentlig disputation .,,,. fiedagen den 6 oktober 2000 kl. 1015 i sal M:B, M-huse; Ole R6mers v~g 1, Lunds Tekniska Htigskola ----- A————— . ——. —.. —-—. .-. --.....—-–—. ----- - - Olganimioss DOcmneutname LUND UNIVERSITY DOcrOIULDISSERTATION DivisionofThermalPowerEngineering Date of issue DepartmentofHeatandPowerEngirteeting September11,2000 LundInstituteofTechnology COD8M ISR3’JLUTIvlDN/TMVK--lO2l--SE Author(s) Spoosxingorganization Mohsenkisadi Titleandsubtitle MethodsandToolsforAnalysisandOptimiition ofPowerPlants Abstract Modemsncieties’timctiorralityisstronslydependentontheelectricity.Eilicientjenvironmentfriendly, and economical pnwer productionhasbeeninfocus for a Iong time. The introduction of computers and drereby computer-aided tools for pm-design studies,optimization and choice of the best opcmtinnal strategies, haa changed the conditions for pnwer production tremendously. The moat noticeable advantage of the intmducrinn nf the computer-aidedteds in the field of power generation, haa been the ability enstudy the plant’s performanceprior tn the construction phase. The results of these studies have nrade it pnasible to change and adjust the plant layout to snatchthe pre-detined requirements. Further developmentof computem in recent yeara haa opened up for implementationof new features in the existing tools and also for the development of new tnols for specific applications, like thernmdynamic and economic optimization, prediction nf the refraining component life time, and fault diagnostics, resulting in impmvenrent of the plant’s performance, availability and reliability. ? The mnat common tmls for predeaign sludies am heat and mass balance programs. Further thermodynamic and economic optimization of plant layouta, generad by the heat and mass balance programs, ean be accomplished by using pinch pmgmms, esersy analysis and tieorro=onotica. Suweihnceand fault diagnostics nf existing systems can be performed by using tnnls like cmufitionmonitoringsystems and artificial neural networks. The increased number of tools and their various cnnatructionand application arms make tbe choice of the most adequate tnol for a cefiin application difiiculL In this thesis the development of different categories of tnnls and tec~lques, and their application arm am reviewed and presented. Case studies on both existing and theoretical power plant layouts have been performed using different commercially available tools to illuminate their advantagea and shortcomings. Tbe development of pnwer plant technologyand the rqdremurts for new tnola and measurementsystems have been briefly reviewed. This thesis contains alan programming techniques and calculation methods concerning part-load calculations using Ineal Iinearizatinn, which has been implemented in an in-house heat and rnaaa balance pmgmm developed by the author. Results nf calculations performed by the in-home pmgmm have been compared with results fmm cnmmcrcial pmgmnrs. The comparison shows gond cmraiaterrcy[1, 2]. Methcds suggested by the author increase the numerical stability, reduce the calculation time, and impmve the user-fiiendlinesaby facilitating free choice of input data. Key words Pre-design, Heat and massbalance,Gashsnbine ~=tioa systemand/orindexterms(iiany) Srrpplsment=ybibliographicalinformation L=&W& En ~s~ ISSNasuikeytftfe LSSN0282-1990 ‘M 91-628-4372-9 rlota Nudes OfpS&S Price Recipklt’s 136 Seeorhy ckifiition . ‘-’’tinDwmon of?(-e”d~)hermal Power engineering,~ Lund Institute of Technology Box 118, S-221 00 LUND, Sweden I,themxkigruc,hewtheeopynght oftheabstract of tbe Arumentioned dkertatfon. hacby grsnt to all mferenee ~t= September 11,2000 Signsmre ——— -———-—--—. —-—-. .—- Methods and Tools for Analysis and Optimization of Power Plants Mohsen Assadi .. LUND UNIVERSITY Lund Institute of Technology October 2000 Doctoral Thesis Division of Power Plant Technology Department of Heat and Power Engineering Lund Institute of Technology SE-221 00 Lund$weden .-. Mohsen Assadi ISBN 91-628-4372-9 ISSN 0282-1990 ISRN LUTMDN/TMVK-102 l-SE Printed in Sweden, KFS AB Lund 2000 DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. —.— Abstract Modern societies’ fimctionality is strongly dependent on the electricity. Efficient environment friendly, and economical power production has been in focus for a long time. The introduction of computers and thereby computer-aided tools for pre-design studies, optimization and choice of the best operational strategies, has changed the conditions for power production tremendously. The most noticeable advantage of the introduction of the computer-aided tools in the field of power generation, has been the ability to study the plant’s petiormance prior to the construction phase. The results of these studies have made it possible to change and adjust the plant layout to match the pre-defined requirements. Further development of computers in recent years has opened up for implementation of new features in the existing tools and also for the development of new tools for specific applications, like thermodynamic and economic optimization, prediction of the remaining component life time, and fault diagnostics, resulting in improvement of the plant’s performance, availability and reliability. The most common tools for pre-design studies are heat and mass balance programs. Further thermodynamic and economic optimization of plant layouts, generated by the heat and mass balance programs, can be accomplished by using pinch programs, exergy analysis and thermoeconomics. Surveillance and fault diagnostics of existing systems can be performed by using tools like condition monitoring systems and artificial neural networks. The increased number of tools and their various construction and application areas make the choice of the most adequate tool for a certain application difficult. In this thesis the development of different categories of tools and techniques, and their application area are reviewed and presented. Case studies on both existing and theoretical power plant layouts have been performed using different commercially available tools to illuminate their advantages and shortcomings. The development of power plant technology and the requirements for new tools and measurement systems have been briefly reviewed. This thesis contains also programmingg techniques and calculation methods concerning part-load calculations using local linearization, which has been implemented in an in- house heat and mass balance program developed by the author. Results of calculations performed by the in-house program have been compared with results from commercial programs. The comparison shows good consistency [1, 2]. Methods suggested by the author increase the numerical stability, reduce the calculation time, and improve the user-friendliness by facilitating fi-eechoice of input data. ——--— -.—— ————.—.———. —— . .- . ii List of Papers 1. Assadi M., Johansson K. B., Applying Pinch Method and ExergY Analysis to a BIO- IGIL4T Power Plant, 2nd Co&erence on Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction, PRES’99, pp. 139-144, Published by Hungerian Chemical Society, Budapest, Hungary, May 31 - June 2, 1999. 2. Assadi M., H5gglund T., A computational investigation of a combined cycle using an SI-engine, a Rankine bottoming cycle and a fuel cell, European Fuel cell news, Newsletter of the European Fuel Cell Group, Ltd., Volume 6, Number 2, pp. 5-7, July 1999. 3. Assadi M., Jansson S. A., Blomstedt M., Increasing thermal eficiency of a PFBC power plant using a natural gas fueled gas turbine, The First lntemationa Symposium on Computer Aided Process Engineering, ISCAPE 2000, Cartagena de india, Colombia, January 24-28,2000. 4. Assadi M., Torisson T., Integration of biomass-fueled power plants and SI-en@”nes, a method for increasing power output from existing plants, 4ti International Cotierence of Iranian Society of Mechanical Engineers, ISME 2000, pp. 409-412, Tehran, Iran, May 16-19,2000. 5. Arriagada J., Assadi M., Air bottoming cycle for Gas Turbines, 4ti International Conference of Iranian Society of Mechanical Engineers, ISME 2000, pp. 447-454, Tehran, IrarL May 16-19,2000. 6. Assadi M., Hildebrandt A., A Computational Investigation of a Biomass Fueled Integrated Gasljication Cascaded Humid Air Turbine, Bio-IGCIiMT, to be presented at 14* International Congress of Chemical Engineering, QUBEC 2000, Sao Paulo, Brazil, September 24-27,2000. 7. Assadi M., Mesbahi E., Torisson T., Lindquist T., Arriagada J., Olausson P., A Novel Correction Technique for Simple Gas Turbine Parameters, submitted to ASME TURBOEXPO 2001, New Orleans, USA. 8. Mesbahi E., Assadi M., Torisson T., Lindquist T., A Unique Correction Technique for Evaporative Gas Turbine (EvGT) Parameters, submitted to ASME TURBOEXPO 2001, New Orleans, USA. ... 111 . .—...—.—.— — ..-:— ..——- .-. iv \ Acknowledgements This work was earned out at the Department of Heat and Power Engineering.
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