Zementklinker ist der Hauptbestandteil von Zement und verbraucht zu dessen Herstellung signifikante Mengen von natürlichen Ressourcen und trägt gleichzeitig zu seiner sehr ungünstigen Treibhausgasbilanz bei. In dieser Arbeit wird gezeigt, dass Zementersatzstoffe mit spezifischen Eigenschaften aus Abfallstoffen wie Kieswaschschlämmen, Strassenwaschschlämmen und Gipskartonplatten ohne Leistungseinbußen auf Produktseite, bei geringeren Temperaturen und geringerer CO2 Emission hergestellt werden können. Entsprechend den angestrebten Eigenschaften solcher zum Teil anthropogener Zementbestandteile wurden lokal verfügbare geeignete Abfallstoffe ausgewählt und thermisch aktiviert. Eine industriell anwendbare Methode zur Aktivierung solcher Stoffe bei Temperaturen von 700 °C – 850 °C wurde entwickelt und patentiert. Es basiert auf einem neu entwickelten Trocknungsverfahren und der Kombination von zwei Produktionslinien, um durch die Verknüpfung der Gasströme beider Systeme eine energieeffiziente thermische Behandlung von Abfallstoffen zu ermöglichen sowie auf umweltfreundliche Weise einen Zementersatzstoff herzustellen.:Table of Contents
List of Tables
List of Figures
List of Abbreviations
Glossary
Chapter 1: Introduction
1.1 Motivation
1.2 Research hypotheses and objectives
1.3 Research methodology
1.4 Thesis outline
Chapter 2: State of the art in SCM production
2.1 Supplementary cementitious materials
2.2 Classification of SCMs
2.2.1 Classification according to origin
2.2.2 Classification according to reaction behaviour
2.3 Chemical composition of SCMs
2.4 Formation of hydraulic or pozzolanic minerals in thermal processes
2.4.1 Cement clinker
2.4.2 Burnt oil shale
2.4.3 Fly ash
2.4.4 Calcined clay
2.5 Performance of composite cements
2.6 Calcining technologies
2.6.1 Flash calciner
2.6.2 Rotary calciner
2.7 Comparison of process technologies
2.8 Summary of Chapter 2
Chapter 3: Alternative SCMs and a new method for activation
3.1 Introduction
3.2 Target of alternative SCM
3.3 Waste materials
3.3.1 Aggregate washing sludge
3.3.2 Road cleaning sludge
3.3.3 Deconstruction gypsum
3.4 Producing alternative SCMs
3.5 Thermal activation of alternative SCMs
3.6 Limitations in current calcining technology
3.6.1 Difficult emission control
3.6.1.1 Particulate emission
3.6.1.2 Gaseous emission
3.6.2 Challenging material preparation
3.6.3 Demand for noble fuels
3.6.4 Difficult colour control
3.6.5 Strict temperature control
3.6.6 CO2 footprint of calciners
3.7 Proposed new method of calcination
3.7.1 Feed material handling
3.7.2 Thermal heat-exchange system
3.7.3 Clay calciner design
3.7.4 Grinding
3.8 Summary Chapter 3
Chapter 4: Theoretical Considerations
4.1 Material considerations
4.1.1 Composition of alternative SCM
4.1.2 Anticipated products and characteristics
4.2 Process considerations
4.2.1 System capacity
4.2.2 Material characteristics
4.2.3 Material receiving, crushing and handling
4.2.4 Thermodynamic modelling
4.2.4.1 Mass balance
4.2.4.2 Drying and cooling heat balance
4.2.4.3 Calcination heat balance
4.2.4.4 Gas balance
4.2.4.5 Impact on clinker kiln line
4.2.4.6 Impact of calcite on the gas balance
4.2.5 Calciner design
4.2.6 Colour control
4.2.7 Emission prediction
4.2.7.1 Emission during drying
4.2.7.2 Emission during calcination
4.2.8 CO2 footprint of produced material
4.2.9 Grinding requirements
4.3 Summary of Chapter 4
Chapter 5: Experimental tests and proof of concept
5.1 Introduction
5.2 Sampling and characterization
5.2.1 Kaolinitic AWS from France
5.2.2 Non-kaolinitic AWS from Switzerland
5.2.3 Road cleaning sludges from Switzerland
5.2.4 Deconstruction gypsum from Switzerland
5.2.5 Sample preparation and shipping
5.3 Drying screw conveyor testing
5.4 Calcination testing
5.4.1 Mineralogy of activated products
5.4.1.1 Non-kaolinitic SCM
5.4.1.2 Kaolinitic AWS from France
5.4.2 Colour
5.5 Crushing tests
5.6 Grinding tests
5.7 Mortar compressive strength testing
5.8 Water demand testing
5.9 Summary of Chapter 5
Chapter 6: Experimental results
6.1 Characteristics of activated materials
6.2 Concrete performance and colour
6.2.1 Thermally activated kaolinitic AWS from France
6.2.2 Thermally activated non-kaolinitic alternative SCM from Switzerland
6.3 Equipment dimensioning
6.3.1 Process mass flow
6.3.2 Heat-exchanging screws and thermal oil system
6.3.3 Rotary calciner dimensioning
6.3.4 Ball mill dimensioning
6.4 CO2 reduction
6.5 Summary of Chapter 6
Chapter 7: Conclusion and outlook
7.1 Conclusions
7.2 Outlook.
Literature
| Identifer | oai:union.ndltd.org:DRESDEN/oai:qucosa:de:qucosa:79811 |
| Date | 30 August 2022 |
| Creators | Weihrauch, Michael |
| Contributors | Bier, Thomas, Charitos, Alexandros, Kruspan, Peter, TU Bergakademie Freiberg |
| Source Sets | Hochschulschriftenserver (HSSS) der SLUB Dresden |
| Language | English |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, doc-type:doctoralThesis, info:eu-repo/semantics/doctoralThesis, doc-type:Text |
| Rights | info:eu-repo/semantics/openAccess |
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