Power Plant Engineering

2

Fuels and Combustion

Contents

2.1 Introduction

2.2 Classification of fuels and different types of fuels used for steam generation

2.3 Calorific values of fuels

2.4 Combustion of fuels

2.5 Properties of coal, indian coals

2.6 Selection of coal in thermal power station

2.7 Questions

2.1 INTRODUCTION

A fuel is a combustible substance that generates heat when burnt in the presence of oxygen. Carbon and hydrogen are the main constituents of a fuel. In addition to these, fuel also contains sulphur, oxygen and nitrogen. Based on the fuel, the percentage of carbon (C) ranges from 50 to 95 per cent, hydrogen (H₂) 2 to 6 per cent, oxygen (O₂) 2 to 4 per cent, sulphur (S) 0.5 to 3 per cent and nitrogen (N₂) 5 to 7 per cent. A solid fuel may ...