Cement Production Technology

Principles and Practice

Anjan Kumar Chatterjee

• Publisher: CRC Press
• Year: 2018
• Print ISBN: 9781138570665
• eBook ISBN: 9781351335737
• Topic: Technology & Engineering
• Subtopic: Civil Engineering
• Index: Technology & Engineering

The book is an outcome of the author's active professional involvement in research, manufacture and consultancy in the field of cement chemistry and process engineering. This multidisciplinary title on cement production technology covers the entire process spectrum of cement production, starting from extraction and winning of natural raw materials to the finished products including the environmental impacts and research trends. The book has an overtone of practice supported by the back-up principles.

ONEBasics of mineral resources for cement production

1.1Preamble

It is said that cement manufacture begins in the quarry (Figure 1.1), which is the commonly used term for opencast mining of minerals and rocks including limestone, the primary raw material for cement production. Since there is hardly any alternative to using limestone for making cement, it is treated as one among the most essential resources of a country. However, given its importance in the economy of any nation, our understanding of the genesis, occurrence, composition, properties, mining, and application of limestone is rather poor. This is because limestone has long been regarded as a “common” rock, and past geological studies were limited in scope, focused essentially on mapping deposits, analyzing rocks, and—occasionally—evaluating aquifers and petroleum reservoirs. However, a different set of data and a deeper understanding are needed to make more efficient use of limestone as a cement raw material. Further, there are certain other naturally occurring raw materials like limestone that are also used in cement manufacture, although in smaller quantities and only when required, and they include clay, bauxite, iron ore, sandstone, and so on. These materials are also obtained from opencast mining operations. Hence, a basic knowledge of geology and mining is important for cement chemists, technologists, and plant engineers. Keeping this in view, this chapter presents the fundamentals of geology, chemistry, and the mining of raw materials as relevant to cement production.

Figure 1.1A view of the limestone quarry at Cedar Creek, Virginia, USA. (Courtesy: Mr Robert Shenk; [email protected].)

1.2Characterization of minerals and rocks

Any naturally occurring chemical compound making up a part of the Earth’s crust is called a mineral. Minerals may occur in solid, liquid, or gaseous form. Natural gas is the best example of the occurrence of minerals in a gaseous state. Petroleum, mercury, and water are the commonest examples of minerals in liquid form. Solid minerals can either be native elements like gold, silver, etc., or compounds like calcium carbonate (calcite), calcium silicate (wollastonite), aluminum silicate hydrate (kaolinite), etc. The last group of solid minerals in the form of simple or complex compounds is of particular relevance for cement manufacture.

Aggregates of such minerals of more or less invariable composition forming independent geological bodies are known as rocks. Depending on their genesis, rocks are classified as igneous, sedimentary, or metamorphic. Igneous rocks are formed by the cooling of the molten mass, called magma, inside the Earth. Primary igneous rock types include granite, syenite, dunite, gabbro, basalt, diorite, etc. Based on their silica content, these rocks are further classified as acidic (SiO2 > 65%), intermediate (SiO2 65–52%), basic (SiO2 52–40%), and ultrabasic (SiO2 < 40%). Amongst the commonly known igneous rocks, granite is acidic and basalt is basic in composition.

Sedimentary rocks are formed by the deposition of the products of weathering of igneous and metamorphic rocks by mechanical, chemical, or organic means from water or air that acts as the carrier of weathering products. Common examples of sedimentary rocks include limestone, sandstone, coal, iron ore, etc. These rocks are the most relevant ones for cement manufacture.

Metamorphic rocks are derived from previously formed rocks of any kind through primarily in-situ action of high pressure and temperature, as well as of chemicals from hot liquids and gases. Quartzite, schist, gneiss, marble, etc. are typical examples of metamorphic rocks.

Minerals and their intrinsic properties

It is common knowledge that the properties of minerals are a function of their chemical composition and system of crystallization. It is possible to have 32 crystal classes belonging to six systems. All these systems and classe...

Table of contents

• Cover
• Half Title Page
• Title Page
• Copyright Page
• Dedication
• Contents
• Preface
• Authors
• Notation
• Chapter one Basics of mineral resources for cement production
• Chapter two Raw mix proportioning, processing, and burnability assessment
• Chapter three Fuels commonly in use for clinker production
• Chapter four Alternative fuels and raw materials
• Chapter five Pyroprocessing and clinker cooling
• Chapter six Clinker grinding and cement making
• Chapter seven Composition and properties of Portland cements
• Chapter eight Advances in plant-based quality control practice
• Chapter nine Environmental mitigation and pollution control technologies
• Chapter ten Trends of research and development in cement manufacture and application
• Chapter eleven Global and regional growth trends in cement production
• Chapter twelve Epilogue
• Index