The ongoing discussion about reaching the "peak-oil point" (maximal delivery rate with conventional methods) emphasizes a fundamental change of the frame conditions of oil-based basic products. The alternative with the largest potential is the use of coal. Coal gasification is the production of coal gas (a mixture of mainly hydrogen and carbon monoxide) from coal adding agents like steam/water and oxygen, which can be used in a number of industrial processes (e. g. hydroformulation and Fischer-Tropsch process). Many different kinds of coal do naturally occur, and due to shrinking natural resources, there has been a substantial gain of interest in poor, ash-rich coal. Beside the quality of coal, there is a number of other parameters influencing the efficiency of coal gasification, such as temperature, pressure, and reactor type.
Although several books dealing with the subject of gasification have recently been published, few are strictly focussed on coal as feedstock. This monograph provides the reader with the necessary chemical background on coal gasification. Several types of coal (baseline coal and ash-rich coal) are compared systematically, pointing out the technological efforts achieved so far to overcome this challenge. Using a new, innovative order scheme to evaluate the gasification process at a glance (the ternary diagram), the complex network of chemistry, engineering, and economic needs can be overviewed in a highly efficient way.
This book is a must-have for Chemical and Process Engineers, Engineering Students, as well as Scientists in the Chemical Industry.
Inhaltsverzeichnis
Preface
INTRODUCTION
COAL GASIFICATION IN A GLOBAL CONTEXT
Applications of Coal Gasification
The Three Generations of Coal Gasifiers
Typical Feedstock and Products
Main Markets for Coal Gasification
Challenges and Opportunities for Coal Gasification
Environmental Aspects
COAL CHARACTERIZATION FOR GASIFICATION
Coal as Gasification Feedstock
Petrographic Coal Analysis
Coal Classification
Coal Sampling
Proximate Analysis
Fischer Assay
Ultimate Analysis
Heating Values
Caking Properties
Reactivity
Mineral Matter and Ash Analysis
Relevant Physical Properties
FUNDAMENTALS
Terms and Definitions
Gasification Reactions
Pyrolysis Reactions
Gasification Parameters
Classifying Gasification Methods
COAL GASIFICATION MODELING
Introduction
Balancing of Gasification Systems
Thermodynamic Modeling
Kinetic Modeling
CFD Modeling of Coal Gasifiers
Generic Models for Case Studies
COAL GASIFICATION TECHNOLOGY SURVEY
Entrained-Flow Gasifiers
Fluid-Bed Gasifiers
Moving-Bed Gasifiers
THERMODYNAMIC PROCESS ASSESSMENT
Introduction of a Ternary Gasification Diagram
Diagrams for Pittsburgh#8 Coal
Diagrams for South African Coal
Technology Potential Analysis
Influence of the Ash Content
Other Gasification Systems
Conclusions
EXERGETIC PROCESS ASSESMENT
Exergy Calculations
Exergetic Analysis
Conclusions of Process Assessment
CONCEPT STUDY: THE INTERNAL CIRCULATION (INCI) GASIFIER
Introduction
Basic Principle
Detailed Process Description
Thermodynamic Modeling of the INCI Gasifier
Next Development Steps
TRENDS FOR GASIFICATION DEVELOPMENT
