3KDVHFKHPLVWU\LQSURFHVVPRGHOVIRU FHPHQWFOLQNHUDQGOLPHSURGXFWLRQ %RGLO+|NIRUV 7KHUPDO(QHUJ\&RQYHUVLRQ/DERUDWRU\ 'HSDUWPHQWRI$SSOLHG3K\VLFVDQG(OHFWURQLFV 'RFWRUDOWKHVLV Phase chemistry in process models for cement clinker and lime production Doctoral thesis Bodil Hkfors Thermal Energy Conversion Laboratory Department of Applied Physics and Electronics SE-901 87 Ume Ume 2014 Copyright©Bodil Hk ors ISBN:978-91-7459-801-8 Front: At the top le t is a microscopy picture o a cement clinker nodule. The igure to the right is a schematic representation o the process modell or cement clinker production that is descri.ed in this thesis. Printed .y: Print 0 1edia2 Ume Uni3ersity2 Ume 2 Sweden 2014 Table of Contents Abstract III Acknowledgements IV Pop l!rvetenskaplig sammanfattning V 1. Introd ction 1 1.1. Sustaina.ility in the cement and lime industry 1 1.1.1. Energy and carbon dioxide (CO 2) 1 1.1.2. Carbon Capture and Storage (CCS) 3 1.2. Chemical calculations2 thermodynamic data and process models 5 1.2.1. Chemical equilibrium calculations and thermo dynamic data 6 1.2.2. Types of process models 6 1.3. The cement and lime production processes 8 1.3.1. The cement process 8 1.3.2. The lime process 10 1.3.3. Specific features of the rotary kiln processes 11 1.3.4. Types of fuel 12 1.3.5. Cement clinker and lime phase chemistry 14 1.3.5.1. Major elements (Ca, Si, ,l, -e and Mg) 14 1.3.5.2. Minor elements (., Na, S, Cl, -, 0, 1n and Ti) 18 1.3.5.3. -uel elements (C, 2, O and N) 18 1.4. Scope o the thesis 20 2. Methods sed in developed process models 21 2.1. Aspen Plus6 21 2.2. ChemApp6 21 2.3. Thermodynamic data rom FACT 22 2.4. Process schemes 22 2.5. Thermodynamic data.ase de3eloped or cement clinker and lime applications 25 2.5.1. -uel definition, including chemistry and enthalpy 26 2.7. Phase chemical e8uili.rium calculations 27 2.6.1. Non equilibrium cooling according to 3ulliver Scheil 27 2.6.2. Energy balance 28 2.7. Strengths and weaknesses o the de3eloped models 28 3. Res lts and disc ssion 31 3.1. 9alidation o simulation models 31 3.1.1. Cement clinker process models 31 3.1.2. 0rocess model of a lime rotary kiln 35 3.1.3. Development of the thermodynamic database 37 3.1.3.1. 7alidation of the clinker composition 38 3.1.3.2. Influence of phosphorus (0) in cement clinker production 42 3.2. Simulated scenarios with 3alidated models 44 I 3.2.1. Oxygen enriched combustion in cement clinker production 45 3.2.2. Influence of co combustion on the lime production process and the lime product 48 3.2.3. 0artial and full oxy fuel combustion in cement clinker production 50 3.2.4. Oxy fuel combustion in lime production 56 4. Concl sions 60 5. Abbreviations 62 6. References 63 II Abstract The goal of the thesis is to evaluate if developed phase chemical process models for cement clinker and lime production processes are reliable to use as predictive tools in understanding the changes when introducing sustainability measures. The thesis describes the development of process simulation models in the application of sustainability measures as well as the evaluation of these models. The motivation for developing these types of models arises from the need to predict the chemical and the process changes in the production process, the impact on the product quality and the emissions from the flue gas. The main chemical reactions involving the major elements (calcium, silicon, aluminium and iron are relatively well known. As for the minor elements, such as sodium and potassium metals, sulphur, chlorine, phosphorus and other trace elements, their influence on the main reactions and the formation of clinker minerals is not entirely known. When the concentrations of minor and trace elements increase due to the use of alternative materials and fuels, a model that can accurately predict their chemistry is invaluable. For example, the shift towards using less carbon intensive fuels and more biomass fuels often leads to an increased phosphorus concentration in the products. One way to commit to sustainable development methods in cement clinker and lime production is to use new combustion technologies, which increase the ability to capture carbon dioxide. Introducing oxy-fuel combustion achieves this, but at the same time, the overall process changes in many other ways. Some of these changes are evaluated by the models in this work. In this thesis, a combination of the software programs Aspen Plus) and ChemApp) constitutes the simulation model. Thermodynamic data from FACT are evaluated and adjusted to suit the chemistry of cement clinker and lime. The resulting model has been verified for one lime and two cement industrial processes. Simulated scenarios of co-combustion involving different fuels and different oxy-fuel combustion cases in both cement clinker and lime rotary kiln production are described as well as the influence of greater amounts of phosphorus on the cement clinker quality. Keywords, Process modelling, phase chemistry, cement clinker, lime, sustainability, CO 2, energy. III Acknowledgements Sincere thanks to many people for making this thesis possible. friends and colleagues at Cementa, Cementa Research and 0me1 0niversity, especially to Rainer 2ackman, Dan 2ostr3m and 4ars 25ckstr3m at 0me1 0niversity, to Erik 7iggh, Stefan Sandelin, 2o-Erik Eriksson, Thomas 4ind and Anders 4yberg at Cementa, to 8atias Eriksson and Kjell Dahlberg at Nordkalk, to Kristina :ohansson and :ohan 4arsson at Cementa Research and to 8arianne Thomaeus and :an 2ida at 8inFo (Swedish 8ineral Processing Research Association . I;m grateful to the Swedish Energy Agency (No. 2006-06679, Project 30A27-1 , to 8inFo and to the Swedish National Research Platform 2ioCEnergy for financial support. 4ast but not least. to great friends, to my family and especially to 4iv, Emil, Dan and Dans, thank youE I9 Populrvetenskaplig sammanfattning Tillverkningen av cement och kalk 5r energiintensiv och inneb5r utsl5pp av stora m5ngder koldioxid (CO 2 . CO 2 har tv1 ursprungsk5llor, CO 2 kan antingen h5rstamma fr1n r1materialet eller fr1n br5nslet. 7id cement- och kalktillverkning best1r r1materialet till stor del av kalksten. N5r kalksten v5rms upp erh1lls den 3nskv5rda kalken och samtidigt bildas CO 2. CO 2 fr1n br5nslet kan minskas genom att energieffektivisera processen, ers5tta traditionella fossila br5nslen med biomassa eller med br5nslen med l5gre kolhalt. Det finns f5rre m3jligheter att minska CO 2 som h5rstammar fr1n r1materialet. Inom cementtillverkning finns m3jlighet att ers5tta en del av r1materialet med restprodukter fr1n j5rn- och st1lindustrin d5r CO 2 redan 5r avdriven. Fenom att rena r3kgaserna fr1n CO 2 kommer man 1t CO 2 fr1n b1de r1material och br5nsle. Tekniken heter CCS (Carbon Capture and Storage och inneb5r att f1nga CO 2 ur r3kgaserna, komprimera och lagra dessa djupt ned i geologiska formationer. Oxy-fuel f3rbr5nning kan med f3rdel kombineras med CCS. D5rvid ers5tts f3rbr5nningsluften helt eller delvis med ren syrgas. F3rbr5nnings- temperaturen 3kar d1 avsev5rt och kontrolleras genom att 1tercirkulera r3kgaser. R3kgasernas koncentration av CO 2 kan d5rmed 3kas fr1n ca 2A till 7AG, vilket ger m3jligheter till effektivare CO 2-avskiljning. 81let med avhandlingen 5r att utv5rdera hur v5l det utvecklade simuleringsverktyget fungerar att anv5nda f3r att f3rutsp1 f3r5ndringars p1verkan p1 produktkvaliteten, tillverkningsprocessen och den yttre milj3n. De anv5nda termodynamiska processmodellerna beskriver de komplexa kemiska reaktionerna i b1de gasfasen och i materialet i respektive tillverkningsprocess. 8odellerna baseras p1 naturvetenskapliga grundregler vilket ger en generell predikterbarhet f3r nya system som 5nnu inte testats i verkliga fall. Tillg5nglig kemisk grunddata 5r utv5rderad och till vissa delar f3rb5ttrad f3r att b5ttre passa f3r cementklinker- och kalktillverkning. 8odellernas riktighet har verifierats med data f3r tv1 cementfabriker och en kalkfabrik. De f3r5ndringar som utv5rderats i detta arbete syftar till 3kad milj3m5ssig h1llbarhet inom cement- och kalkindustrin. 8odellerna kan anv5ndas till att studera inverkan av f3r5ndringar s1 som inf3rande av nya slags br5nslen, energieffektiviserings1tg5rder och nya f3rbr5nningsteknologier. Resultateten skulle ytterligare f3rb5ttras med ut3kade och f3rb5ttrade termodynamiska data och om modellen kompletterades med m3jlighet att simulera stoftbildning i gasfasen. 9 List of papers This thesis is based on the following papers, which are separately appended and referenced by their corresponding roman numerals, I to 7I, in the text. I A predictive chemistry model for the cement process 2. Wilhelmsson D3kfors, E. 7iggh and R. 2ackman. HKF International 7 (200I 60-70. In Chinese, HKF China 3 (200I C0-CC. In Russian, HKF Russia 2 (2009 A3-AI. II Improved process modeling for a lime rotary kiln using equilibrium chemistry 2. D3kfors, 8. Eriksson and R. 2ackman. :ournal of Engineering Technology (2012 Spring I-1I. III Oxy-fuel combustion in rotary kiln lime production 8. Eriksson, 2. D3kfors and R. 2ackman. Submitted to Energy Science J Engineering. IV Modelling the cement process and cement clinker quality 2. D3kfors, 8. Eriksson and E. 7iggh. Advances in Cement Research (201C . DOI, 10.16I0/adcr.13.000A0 V On the phase chemistry of Portland cement clinker 2. D3kfors, D. 2ostr3m, E. 7iggh and R. 2ackman. Accepted 30 th :anuary 201C to be published in Advances in Cement Research. VI Simulation of oxy-fuel combustion in cement clinker manufacturing 2. D3kfors, E. 7iggh, and 8. Eriksson. Accepted 6 th :anuary 201C to be published in Advances in Cement Research. Reprints have been included within this thesis with permission from the publishers. 9I 1 Introduction 1 1 Sustainability in the cement and lime industry 1.1.1. Energy and carbon dioxide (CO 2) The world;s cement production was 3.6 billion tonnes in 2012 and is expected to increase (I8F, 2013 .