TM 5-815-1/AFR 19-6
CHAPTER 2
INCINERATOR EMISSIONS
2-1. Incineration
solid, semi-solid, liquid, or gaseous waste at specified
rates, so that the residues contain little or no combusti-
This chapter describes and quantifies whenever possi-
ble material. In order for an incinerator to meet these
ble the air pollution particulate emissions which are the
specifications, the following principles of solid fuel
direct result of the incineration process.
combustion generally apply:
a. Incineration process. The incineration process
-- Air and fuel must be in the proper proportion,
consists of burning solid, semisolid, liquid, or gaseous
-- Air and fuel, especially combustible gases, must
waste to produce carbon dioxide, water, and ash. It is
be properly mixed,
an efficient means of reducing waste volume. The
solid, incombustible residue of incineration is inert,
-- Temperatures must be high enough to ignite
sanitary, and sensibly odorless.
both the solid fuel and the gaseous components,
b. Emissions. Incineration contributes to air pollu-
-- Furnace volumes must permit proper retention
tion. The polluting emissions are ash, hydrocarbons,
time needed for complete combustion,
-- Furnace configurations must maintain ignition
and carbon monoxide. Estimating absolute quantities
temperatures and minimize fly-ash entrainment.
of these pollutants is not an exact science, hut historical
testing data from typical incinerators allow estimates of
2-4. Effect of waste properties
emissions to be made. Also, measurement methods for
The variability of chemical and physical properties of
incinerator emissions are sufficiently advanced to per-
waste materials, such as ash content, moisture content,
mit actual data to be obtained for any existing incin-
volatility, burning rate, density, and heating value,
erator. These measurements are preferred in all cases
makes control of incineration difficult. All of these fac-
over analytical estimates.
tors affect to some degree the operating variables of
c. Pollution codes. Air pollution particulate emis-
sions must be considered in regard to federal, state and
flame-propagation rate, flame travel, combustion tem-
local pollution codes. In general, incinerators cannot
perature, combustion air requirements, and the need
meet current pollution code requirements without par-
for auxiliary heat. Maximum combustion efficiency is
ticulate control devices.
maintained primarily through optimum incinerator
design.
2-2. Types of incinerator waste materials
Waste materials are classified as shown in table 2-1.
2-5. Types of incinerators
An ultimate analysis of a typical general solid waste is
a. Municipal incinerators. Incinerators are classified
shown in table 2-2. Because of the wide variation in
either as large or small units, with the dividing point at
composition of waste materials, an analysis of the
a processing rate of 50 tons of waste per day. The trend
actual material to be incinerated should be made before
is toward the use of the smaller units because of their
sizing incineration equipment.
lower cost, their simplicity, and lower air emission
control requirements. There are three major types of
municipal incinerators.
(1) Rectangular incinerators. The most common
municipal incinerator is the rectangular type.
The multiple chamber units are either refrac-
tory lined or water cooled and consist of a
combustion chamber followed by a mixing
chamber. The multicell units consist of two
or more side-by-side furnace cells connected
to a common mixing chamber. Primary air is
fed under the grate. Secondary air is added in
the mixing chamber to complete combustion.
A settling chamber often follows the mixing
2-3. Function of incinerators
chamber. Ash is removed from pits in the
Incinerators are engineered apparatus capable of with-
bottom of all of the chambers.
standing heat and are designed to effectively reduce
2-1
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