Coal calorific value measurement - Huaqiang Electronic Network

Probe current voltage pin 420*4450 head diameter 5.0 over current current and voltage pin

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Coal calorific value measurement -

/ Calorimeter: The calorific value of coal refers to the amount of energy released when it is burned. A device used to measure the calorific value of coal is called a calorimeter. The unit for coal calorific value is typically in kilojoules per kilogram (kJ/kg) or megajoules per kilogram (MJ/kg). In China, it's often expressed in calories, where 1 calorie equals 4.186 joules.

A calorimeter is a sophisticated instrument that measures the heat released during combustion. It generally consists of several key components including a combustion oxygen bomb, an inner cylinder, an outer cylinder, a stirrer, temperature sensors, and a sample ignition system. The entire setup is designed to ensure accurate and repeatable measurements.

The oxygen bomb is constructed from high-temperature and corrosion-resistant materials such as chromium-nickel alloys. It must be able to withstand extreme conditions during combustion, maintain airtight integrity, and resist chemical damage from combustion byproducts. The inner cylinder, usually made of copper or stainless steel, holds water and is surrounded by the outer cylinder, which helps minimize heat loss. The space between the inner and outer cylinders is typically 10–12 mm, and the outer cylinder is insulated at the bottom to support the inner cylinder.

The stirrer inside the calorimeter rotates at a controlled speed (around 400–600 rpm) to ensure even mixing of the water and consistent heat distribution. The temperature measuring system requires high precision, with a resolution of at least 0.001K to accurately capture small temperature changes during the test.

Additional components include a combustion dish, pressure gauge, ignition system, press cake machine, stopwatch, and balances. The combustion dish is typically made of platinum or nickel-chromium steel, while the ignition system uses a low-voltage power supply and is calibrated based on the type of ignition wire used (e.g., cotton or wire). The press cake machine compresses coal samples into a compact form for testing, ensuring uniformity in the sample.

Common calorimeters used in coal analysis include models like the ZDHW-2002 automatic calorimeter, ZDHW-6 microcomputer calorimeter, and Others. These instruments are widely used in metallurgical industries and coal processing plants for precise calorific value determination.