Mobile gas sample collector
Gases fed into the grid are ever more diverse: natural gas and LNG from various origins, biomethane and hydrogen from Power to Gas plants result in permanently increasing in local and time-related fluctuations in gas quality. In order to ensure correct billing and monitor technical regulation specifications, it is becoming increasingly important to be aware of gas composition and relevant parameters.
Simple but exact gas quality determination
GasPro facilitates simple but exact average gas quality assessment by means of cyclical sampling and subsequent chromatographic analysis. The mobile sample collector features simple commissioning and use, and it can be deployed at practically any grid location. In this way GasPro is highly flexible and represents a useful alternative to permanent gas chromatography installations.
This is how GasPro works
On a cyclical basis the gas sampler removes a predetermined sample quantity from the pipeline. The gas mixtures collected in this way thus reflect average gas quality over the sampling period. Subsequently these gas samples collected are analysed in a certified laboratory or state-accredited testing station; gas composition can then be calculated in terms of all relevant parameters such as calorific value and Wobbe Index. In this way it is also possible to test the gas quality for trace substances such as oxygen.
Typically samples are taken over a period of 4 days, and so a cycle time of 15 minutes produces 384 samples. There is an option for configuring other sampling periods and cycle times. GasPro can be constructed outside with power supplied by a free-standing built-in battery. In this way gas quality can be assessed at practically any grid location. With the included software the sample collector can be configured (sample periods, cycle times), measured data are retrieved and operational conditions are displayed.
Applicable in a variety of situations
Thanks to its mobile nature GasPro can be deployed at practically any grid location. This opens up a whole series of possibilities:
• Assessment of natural gas quality with respect to corresponding regulations (e. g. DVGW) at representative grid locations, especially at network interconnection points and in supply areas with feed-in involving differing gas qualities.
• Validation of gas quality tracking systems (SmartSim): comparison of simulated gas parameters with GC analysis of GasPro´s gas samples.
• When used at biogas plants, it is possible to test both the raw biogas and also biomethane fed into the grid in terms of calorific value, Wobbe Index and trace substances.
• When Power to Gas plant feed hydrogen into the grid, both the hydrogen purity before injection and the hydrogen concentration after feed-in can be monitored.
The gas sample collector was developed in cooperation of E.ON and Ehrler Prüftechnik. It consists of two housing parts; gas-leading components are found in the upper element (Ex area), controls and power supply (battery) are underneath.
• Sample duration can be adjusted
• Operating pressure 4 - 16 bar
• Temperature range: -20 to +50°C
• Power supply voltage: 24 VDC / optional 230 VAC
• Battery life approx. 2 years
• Independent operation possible
• Can be deployed outside
• Sample cylinder volume 500 ml
• ATEX compatible
• Approval for use in gas parameter custody transfer assessment expected early 2016.
• Uncertainty of calorific value due to sampling process < 0.1%