INTRODUCTION
In any manufacturing plant, energy consumption is a major portion of operating cost.
Energy consumption worldwide is expected to increase 1.4% per year over the next
25 years, from 200 to 307 quadrillion Btu, as shown in Figure 9.1 [1]. Energy is required
for running process equipment, for generating steam, for lighting, and for heating and air
conditioning. The petrochemicals and refinery industries are energy intensive, consuming
over 25% of total energy.
Furnaces and boilers are an integral part of most sites in the process industries.
Furnaces are commonly used to process hydrocarbon feeds, and they often also include
convection banks that produce steam. Boilers, in contrast, are used to produce only
steam. In many process plants, fired duty in furnaces and boilers is the largest single
energy input. Individual furnaces and boilers are energy intensive, and therefore it is
important to design and operate these units at the best possible efficiency. While many
boilers operate under near-constant conditions, furnace operation is often very dynamic.
A major product group in the heart of petrochemical industry is ethylene and other
olefins, which are used in the manufacture of plastics and many other derivatives. More
than 60% of the energy consumption in a typical olefins plant is in the furnaces. Olefins