Bomb calorimetry is an essential technique for determining calorific values across a wide range of applications, including coal, fuel oils, gasoline, combustible waste, food, construction materials, explosives, and more. The method measures the heat of combustion by comparing the energy released from a sample to that of a standard reference material. During the test, the sample is combusted in a high-pressure oxygen environment inside a sealed metal pressure vessel, known as the bomb. The released energy is absorbed by the surrounding system, and the resulting temperature increase is accurately recorded.
Every bomb calorimeter consists of four core components:
- an insulating jacket to minimize thermal disturbances,
- a bucket with a stirring mechanism to hold the bomb and water,
- the bomb, where combustion takes place,
- a thermometer to measure temperature changes precisely.
Different calorimeter models integrate these components with varying levels of technological sophistication to match specific analytical requirements."
Calorimeter Design Features
Isoperibol Calorimetry
An isoperibol calorimeter, such as the Model 6400 and 6200 Calorimeters, maintains a constant temperature in the surrounding jacket while allowing the temperatures of the bomb and bucket to rise as heat is released during combustion. These systems use a microprocessor-based controller to continuously monitor and correct temperature differences between the bucket and the jacket, ensuring accurate and stable measurements throughout the test.
Continuously Compensated Calorimetry
The Parr 6100 and 6050 Calorimeters apply a real-time, continuously compensated approach to isoperibol calorimetry. The jacket temperature is actively adjusted based on the temperature difference between the bucket and the jacket.
This method delivers results comparable to conventional isoperibol calorimetry, although it does not reach the same level of temperature uniformity as systems equipped with a circulating water jacket.
Compensated Calorimetry
The Parr 6772 Calorimetric Thermometer, when used with the 1341 or 6725 Calorimeters, applies an alternative approach to emulate isoperibol calorimetry. It precisely measures heat leakage during the calorimetric pre-period to estimate the average temperature of the surrounding environment.
This value is then used for heat-leak correction throughout the experiment, delivering results comparable to non-electronic thermometry and traditional manual calorimetric methods—without additional hardware investment.
Model 6400 Automatic Isoperibol Calorimeter
Designed for laboratories requiring high throughput, the Model 6400 features a closed-loop cooling subsystem and the highest level of automation in bomb calorimetry.
Its patented Quick Twist-Lock vessel closure allows a single operator to run up to four instruments simultaneously, maximizing productivity.
Model 6200 Isoperibol Calorimeter
The Parr 6200 is the most widely used calorimeter in the range. Its removable bomb and bucket design makes it ideal for high-precision quality control and R&D applications.
Multiple bomb configurations are available, extending application flexibility.
Model 6100 Compensated Jacket Calorimeter
The Parr 6100 uses a real-time, continuously corrected calorimetric method originally developed by Parr.
This approach delivers excellent accuracy and is well suited for coal testing, waste analysis, refuse-derived fuels, and similar applications.
Model 6050 Compensated Jacket Calorimeter
The Model 6050 is the first Parr calorimeter designed for direct control via a personal computer.
This compact, cost-effective system combines a static jacket with automated oxygen filling, offering a strong balance between performance and affordability.
Model 1341 Plain Jacket Calorimeter
A reliable and economical solution, the 1341 supports the same wide range of solid and liquid combustible samples as more advanced systems.
Its simple design makes it suitable for low-throughput testing, sample screening, and educational laboratories.
Model 6725 Semimicro Calorimeter
The 6725 Semimicro Calorimeter is a compact static jacket system designed for very small sample sizes.
It is particularly well suited for marine biology research and applications where sample availability is limited.
Model 6755 Solution Calorimeter
The 6755 Solution Calorimeter is intended for laboratories measuring enthalpy changes from chemical reactions in solution.
Model 6765 Combination Calorimeter
For laboratories requiring both solution calorimetry and semimicro oxygen bomb calorimetry, the 6765 Combined Calorimeter provides a flexible solution.
It includes the 6772 Calorimetric Thermometer, a calorimeter module, and conversion components for both the 6755 and 6725 systems.
This configuration is particularly popular in teaching laboratories.
Conversion Sets
The 6729 and 6759 Conversion Sets allow users to add a second calorimetric capability to an existing system.
Model 6772 Calorimetric Thermometer
The 6772 is a high-precision temperature measurement system compatible with Models 1341, 6725, and 6755.
It includes an ignition firing system and stirrer motor output.
PARR CALORIMETER SELECTION GUIDE
Ask a quotation
From the advanced 6400 Automatic Isoperibol Calorimeter with the 1138 Oxygen Bomb to the 1341 Plain Jacket Calorimeter using the industry-standard 1108 Oxygen Bomb, Parr delivers quality, reliability, and world-class support.
