New Index Wobbe Analyser And Calorific Value

With the new ETG 6700 from ETG (Italy) it is possible to measure the calorific value or Wobbe index in a  simple, fast and safe way with an analysis of each gas in the mixture without carrier gas. The system is based on a "tunable" IR filter with which it is possible to avoid all the complications of hydraulic and pneumatic circuits typical of the GC and the residual oxygen technique. The variations in the mixtures of combustible gases can be harmful in the production of energy within, for example: furnaces, turbines, internal combustion engines, fuel cell systems, boilers, etc. Some parameters such as the calorific value of the fuel or Wobbe index are important to measure in real-time to ensure optimal and safe function.

The two technologies commonly used on this type of application are: gas chromatography (GC) and the analysis of the residual oxygen. For applications that require response in real time the only option is an oxygen analyser residual as a GC takes minutes for analysis.

However, the restriction with a residual oxygen analyser is that it does not provide the value of the composition in the various constituent elements (hydrocarbon components).

Therefore, applications that require this type of information are obliged to use both systems (GC + residual O2). This creates both cost and practical problems as they require hydraulic circuits, sample conditioning, calibration methods, carrier gas, gas and fuel for the instrument, limitations for hazardous areas, technical interventions etc.

Based upon patented tunable filter technology  the ETG 6700 is 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 analyser 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.