Field of the Invention
The invention relates to a method for measuring the components and calorific value of coal gas.
Description of the Related Art
As a typical manual chemical analyzer, Orsat gas analyzer is characterized by low price, convenient operation and easy maintenance. However, the manual operation has low accuracy and low speed, and cannot meet the needs of industrial development. In recent years, the chromatograph has been promoted widely, but the gas to be tested must be separated using a plurality of chromatographic columns in the presence of a carrier gas, which causes the difficulty in the real-time online test.
Infrared gas analyzers have been used for years, but the technology can only analyze one or two components. In addition, gas analyzers suffer from high price and complex maintenance, and cannot accurately measure the amount of CH4 in the coal gas due to interference from other hydrocarbons. The volume concentration of H2 and O2 in the coal gas cannot be measured using a nondispersive infrared (NDIR) method. The volume concentration of H2 is usually measured with a thermal conductivity detector (TCD), and that of O2 is measured with an electrochemical detector (ECD). CH4 and other CnHm in the coal gas interfere with each other, and CH4 and CO2 interfere with H2.
Due to the significant mutual interference of CnHm and CH4, it is very difficult to accurately measure various components in the coal gas, especially CH4, CnHm, CO and H2 which provide the main source of calorific value. Therefore, it is necessary to develop a method to accurately measure a variety of components in the coal gas, calculate the calorific value of coal gas, and effectively eliminate the interference between gases.