Keeping track of combustible gases

Instrumentation specialist ETG Risorse has introduced its ETG 6700 with which it is apparently possible to measure the calorific value or Wobbe index of a gas mixture in a simple, fast and safe manner, receiving an analysis of each gas in the mixture and above all without the use of a carrier gas.

Many applications present a need to keep track of variations in the quantities of combustible gases present.
Many applications present a need to keep track of variations in the quantities of combustible gases present.

The system is based on a tunable IR filter, avoiding the complications associated with hydraulic and pneumatic circuits typical of gas chromatography and the residual oxygen technique.
The device is relevant to applications like furnaces, turbines, internal combustion engines, fuel cell systems, boilers, and so on. Finding the optimal level of energy production requires keeping track of variations in the composition of mixtures of combustible gases present.
Some parameters such as the calorific value of the fuel or Wobbe index are important to measure in order to have a real-time system functioning optimally and safely.
The two technologies commonly used in this type of application are: gas chromatography (GC) and analysis of the residual oxygen. For applications that require response in real time the only option is the latter as a GC takes minutes for analysis.
However, residual oxygen analyzers do not provide a reading of the composition of the various hydrocarbon constituents that might be present. Applications that require this type of information are obliged to use both systems (GC + residual O2). This in turn presents requirements such as hydraulic circuits, sample conditioning, calibration methods, carrier gas, and gas and fuel for the instrument. This kind of setup also has limitations when used in hazardous areas.
Based upon patented tunable filter technology the ETG 6700 is said to be capable of high-accuracy fuel gas composition measurements every 5 seconds.
The ETG 6700 gas analyzer can calculate the calorific value, Wobbe Index and other gas properties in real time. This compact, stand-alone and all-optical transmitter style analyzer provides real-time data through Modbus digital interfaces.
The ETG 6700 requires no carrier-gases, no-calibration gases and offers fast-response analytics without compromising accuracy, repeatability, linearity or stability in the presence of interferences.