The increasing global demand for energy implies a diversification in gas production and puts a stronger focus on the development of unconventional natural gas sources, such as shale gas and coal seam gas. As a direct consequence, the number of unconventional natural gas wells increases worldwide.
Gas flow meters located close to the wellhead or at the gathering station are commonly used to monitor unconventional gas production. Depending on the reservoir and the quality of the gas treatment equipment on the wellhead, the gas may contain liquids and containment. Depending on their volume fraction, these liquids and containments can degrade the flow meter measurement performance and in turn negatively impact the monitoring reliability. The output of the gas well also may fluctuate unpredictably on relatively short timescales and will generally decline over longer time periods. Monitoring a time-varying production rate requires a robust flow meter with high turn-down and minimized operational costs to cope with economic requirements.
Gas metering points in this production environment are traditionally equipped with differential pressure meters even though new gas meters like ultrasonic meters provide several advantages over differential pressure technologies. In the last few years, gas producers have experienced lower operational expenditures and technology benefits from ultrasonic meters that compensate for the higher initial investment. This has made ultrasonic meters for gas production applications become more accepted.
SICK took an innovative approach for an ultrasonic gas production meter that provides high reliability, rangeability and class 1 uncertainty in dry conditions without the need for an individual high-pressure natural gas calibration.
*The US standards that would apply to this article are custody transfer measurement as presented in AGA Report No.9
Download the technical paper below to learn more about the technical challenges that have been overcome in order to ensure a proper meter performance in high-pressure natural gas without high-pressure calibration.