Page 370 - Air Pollution Control Engineering

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Thermal Oxidation

Lawrence K. Wang, Wei Lin, and Yung-Tse Hung

CONTENTS
INTRODUCTION
PRETREATMENT AND ENGINEERING CONSIDERATIONS
SUPPLEMENTARY FUEL REQUIREMENTS
ENGINEERING DESIGN AND OPERATION
MANAGEMENT
DESIGN EXAMPLES
NOMENCLATURE
REFERENCES

1. INTRODUCTION
1.1. Process Description

Thermal oxidation (thermal incineration) is a widely used air pollution control
technique whereby organic vapors are oxidized at high temperatures. Incineration (both
thermal oxidation and catalytic oxidation) is considered an ultimate disposal method in
that organic compounds in a waste gas stream are converted to carbon dioxide, water,
and other inorganic gases rather than collected. In thermal incineration, contaminant-
laden waste gas is heated to a high temperature (above 1000ºF) at which the organic
contaminants are burned with air in the presence of oxygen (see Figs. 1 and 2). A major
advantage of incineration is that virtually any gaseous organic stream can be incinerated
safely and cleanly, given proper design, engineering, installation, operation, and main-
tenance. Also, high (99% and higher) destruction efficiencies are possible with a wide
variety of emission streams.
Depending on the types of heat recovery unit, incinerators are further classified as
regenerative and recuperative. A recuperative thermal incinerator uses a shell and tube
heat exchanger to transfer the heat generated by incineration to preheat the feed stream.
Recuperative incinerators can recover about 70% of the waste heat from the exhaust
gases. Regenerative thermal incinerators consist of a flame-based combustion chamber
that connects two to three fixed beds containing ceramic or other inert packing.
Incoming gas enters one of the beds where it is preheated. The heated gas flows into the
combustion chamber, burns, and the hot flue gases flow through the packed beds where

From: Handbook of Enviromental Engineering, Volume 1: Air Pollution Control Engineering
Edited by: L. K. Wang, N. C. Pereira, and Y.-T. Hung  Humana Press Inc., Totowa, NJ
347