Whether you want to monitor power stations, examine gas in chemical industry, see rotating furnaces in cement work, a gas analyzer ensures highest reliability and accuracy for the constant observation of process gases. Here is a simple guide on how to use one.
Gas Analyzers- There are many kinds of gas analysers- dissolved oxygen analyzer, carbon monoxide analyzer, and carbon dioxide analyzer and each has a different principle of working.
Dissolved oxygen analysers have cells which only allow electricity to pass through oxygen. One side has a reference concentration and second side the sample. The difference in concentrations creates a voltage difference due to the difference in conductivity which is then measured.
Whereas, CO and CO2 analysers use the absorption of infrared light of a particular frequency to measure the concentration. The more the absorption, the more the concentration.
Some things should be remembered and considered before using or buying a gas analyzer:
- The sample of gas is taken through an inlet with knobs that can regulate the sampling flow rate to suit various applications. More advanced and small gas analysers select a sample size that suits most of the purposes.
- Your sample won’t only contain the gases but also the dirt particles and other impurities. thus, dust caps are required when analyser is not in use and filters when in use. Not removing the dust caps from inlet and exhaust ports before starting the pump is a common and embarrassing mistake which should be avoided.
- Ensure that at least 10 minutes of the pump action is on before the reading is taken. Otherwise, the large offset of the gases already in the analyser can disrupt the readings.
- The inlet and outlet passage should remain clear.
- To increase the life of transducers, the sample should remain moisture free.
For dissolved oxygen analyzer the Measuring range should be around 0 to 20.0 mg/L with a resolution of 0.1 mg/L and accuracy of 0.4 mg/L.
For CO and CO2 analyzers the good measuring Range of 0 to 1000 ppm with a Resolution of 1 ppm and Accuracy of ± 10ppm(or 5 % for the cheaper ones) is suitable for various applications. Gas analyzer price varies from 9,000 to 45,000, reliability, display and accuracy being the factor there.