Introduction: Bomb Calorimetry
Calorimeter Selection
B
omb calorimetry is a fundamental test of great
significance to anyone interested in calorific
measurements. The following list includes possible
applications:
• Coal and coke, all varieties and types
• Fuel oil, both heavy and light varieties
• Gasoline, all motor fuel and aviation types jet
fuels, all varieties
• Combustible wastes and refuse disposal
• Foodstuffs and supplements for human nutrition
• Forage crops and supplements for animal nutrition
• Building materials
• Explosives and heat powders
• Rocket fuels and related propellants
• Thermodynamic studies of combustible materials
• Energy balance studies in ecology
• Instruction in basic thermodynamic methods
Heats of combustion, as determined in an oxy-
gen bomb calorimeter, are measured by a substitu-
tion procedure in which the heat obtained from the
sample is compared with the heat obtained from a
standardizing material. In this test, a representative
sample is burned in a high-pressure oxygen atmo-
sphere within a metal pressure vessel or “bomb”.
The energy released by the combustion is absorbed
within the calorimeter and the resulting temperature
change is recorded.
Four essential parts are required in any bomb
calorimeter: (1) an insulating jacket to protect the
bucket from transient thermal stresses during the
combustion process, (2) a bucket for holding the
bomb in a measured quantity of water, together
with a stirring mechanism, (3) a bomb in which the
combustible charges can be burned and (4) a ther-
mometer or other sensor for measuring temperature
changes within the bucket. Different model calo-
rimeters will incorporate these parts with varying
degrees of technology.
T
here are a number of factors which should influ-
ence a user in the selection of a calorimeter. In
general, these four areas will help define the correct
calorimeter choice:
1. Anticipated Workload
2. Required Precision
3. Appropriate Standard Methods
4. Available Budget
For those laboratories testing a large volume of
samples, the 6400 Automatic Isoperibol Calorimeter
is an appropriate choice. Loading of the sample
involves a simple 1/16th turn of the bomb head in
the unit. The calorimeter then automatically fills the
bomb and bucket, ignites the sample, monitors the
temperature rise and flushes the system once the
reaction is complete. Users will find that they can
operate multiple calorimeters with ease. The opera-
tor time per test is estimated to be 1 minute and
therefore it is possible for one operator to manage
multiple units simultaneously.
The 6200 Isoperibol Calorimeter and the 6100
Compensated Jacket Calorimeter can analyze just as
many samples per instrument as an individual auto-
matic calorimeter; however, there is additional oper-
ator time per test and therefore fewer instruments
can be operated at the same time. The operator time
per test is estimated to be 6 minutes.
The 1341 Plain Jacket Calorimeter requires signifi-
cant user time. The user must record the tempera-
tures during the course of the reaction. The estimat-
ed time that the user will spend with this instrument
is 25 minutes per test. This process can be simpli-
fied for the user by adding the 6772 Calorimetric
Thermometer.
See page 9 for Selection Guide.
O x y g e n C o m b u s t i o n C a l o r i m e t e r s
B u l l e t i n 6 0 0 0
5
1 - 8 0 0 - 8 7 2 - 7 7 2 0
