How To Measure a Gas Accurately Using a Flue Gas Analyzer?
What Is an Analyzer Flue Gas?
An analyzer flue gas system is used to measure and analyze gases produced by combustion for emissions testing, combustion efficiency, and equipment diagnostics. More commonly called a flue gas analyzer, this type of instrument can range from a compact handheld device for field testing to a larger stationary system permanently installed at an industrial facility.
A modern analyzer flue gas system can measure multiple gases, provide readings in real time, and store measurement data for later review. Some systems also provide data transfer and reporting capabilities, allowing technicians and industrial facilities to document combustion and emissions measurements.
How Does an Analyzer Flue Gas System Work?
An analyzer flue gas instrument collects a sample from the exhaust or flue of a combustion system and analyzes the gases present in that sample. The equipment may be used with boilers, furnaces, heating systems, engines, and other sources of combustion.
A flue gas analyzer typically uses a sampling probe positioned inside the flue. The analyzer draws a sample through the probe and sampling line before measuring the gases with its internal sensors.
The specific measurement technology depends on the gases being analyzed. Some analyzer flue gas systems use infrared technology, while others use electrochemical sensors. Multi-gas instruments can combine different sensor technologies to measure several gases simultaneously.
What Does an Analyzer Flue Gas Measure?
An analyzer flue gas instrument can measure different combustion gases depending on the model and application. Common measurements include oxygen (O₂), carbon monoxide (CO), carbon dioxide (CO₂), nitrogen oxides (NOₓ), sulfur dioxide (SO₂), and other gases associated with combustion and industrial emissions.
These measurements can provide valuable information about combustion performance and exhaust composition. For example, oxygen and carbon monoxide readings can help technicians evaluate combustion conditions, while measurements of specific pollutants can provide information about emissions.
Flue Gas Sampling and Probes
A sampling probe is one of the most common components used with a flue gas analyzer. The probe is positioned in the flue to collect a representative sample of the exhaust gas.
However, an analyzer flue gas system does not necessarily have to perform the measurement directly at the probe. Some systems use a pump to draw the sample through a tube or sampling line and transport it to the analyzer.
Proper sample collection is important because temperature, moisture, particulates, and other characteristics of the exhaust can affect gas measurements.
Why Does Flue Gas Need to Be Conditioned?
Some applications require the gas sample to be conditioned before it reaches the sensors. Hot or wet exhaust can create challenges for an analyzer flue gas system because moisture or certain gases may condense in the sampling line.
Heated sampling lines can help prevent condensation when measuring gases that could otherwise change from a gas to a liquid before reaching the analyzer. Maintaining the appropriate sample temperature can help preserve the composition of the gas being measured.
Other applications require the sample to be cooled. A Peltier cooler can reduce the temperature of the sample and remove moisture before the gas reaches the analyzer. Proper gas conditioning can help protect the instrument and improve the reliability of measurements.
Analyzer Flue Gas Technology
Different analyzer flue gas systems use different measurement technologies based on the gases being measured. Infrared technology, including non-dispersive infrared (NDIR), is commonly used for gases that absorb infrared radiation.
Electrochemical sensors are also widely used for combustion gas measurement. The appropriate technology depends on the target gas, concentration range, temperature, moisture, and other characteristics of the application.
A professional multi-gas flue gas analyzer may combine infrared and electrochemical technologies to measure multiple gases with one instrument.
Analyzer Flue Gas for Combustion Efficiency
An analyzer flue gas system can help technicians evaluate combustion efficiency by measuring the gases produced during combustion. Oxygen, carbon monoxide, and carbon dioxide measurements can provide useful information about how effectively fuel is being burned.
Flue gas measurements can also help identify combustion conditions that may require adjustment or maintenance. Portable analyzers allow technicians to perform these measurements directly at the equipment rather than sending samples to a separate testing facility.
Analyzer Flue Gas for Emissions Testing
A flue gas analyzer can be used for emissions testing and monitoring applications. Measuring the gases in an exhaust stream provides information about the pollutants and combustion products being released by boilers, furnaces, engines, and other equipment.
Portable analyzer flue gas equipment is particularly useful for periodic emissions measurements, commissioning, troubleshooting, maintenance, and combustion analysis. For applications requiring continuous emissions monitoring, stationary gas analysis and CEMS equipment may be more appropriate.
Choosing an Analyzer Flue Gas System
When selecting an analyzer flue gas system, consider the gases that need to be measured, expected concentration ranges, flue temperature, moisture content, sampling requirements, and whether the analyzer will be used for portable or stationary testing.
It is also important to consider sensor technology, gas conditioning, sampling equipment, data storage, and the environment where the instrument will be used. Choosing equipment designed for the specific application can help provide accurate and dependable gas measurements.
MRU Instruments offers professional gas analysis equipment for combustion, emissions, and industrial applications. Our flue gas analyzer solutions are designed for users who need dependable measurements of combustion gases and exhaust emissions.
Whether you are searching for an analyzer flue gas system for combustion efficiency testing, emissions analysis, boiler testing, furnace analysis, or industrial applications, MRU Instruments provides professional gas measurement equipment designed for field and industrial use.
