This is where a flow computer can help. This, when combined with Coriolis mass flow measurement, provides a more accurate picture of the actual conditions, taking into account the presence of other gases, along with other key variables. Coriolis mass flow measurement has been used for many years in oil and gas custody transfer applications and is widely considered to be one of the most accurate and cost-effective measurement techniques. Its advantages also make it a logical choice for the measurement of hydrogen. Coriolis meters operate on the mass flow measurement principle and are favored for their ability to measure multiple attributes over sustained periods with high repeatability and little maintenance requirements. The latest generation of devices from manufacturers such as ABB can measure a wide range of medium characteristics including aggregate state, conductivity, and density with an accuracy to 0.1% in direct mass flow measurement.
From the mass flow rate, fluid density and temperature measurements taken by a Coriolis meter, other measurement values can be inferred from the data, such as volumetric flow rate and percent concentration. A single Coriolis meter can therefore carry out the work of multiple instruments, saving money by reducing the need for separate devices, while also cutting down maintenance.
A flow computer is an electronic device that takes inputs from the flowmeter along with pressure and temperature sensors to compute a correct volume flow. In this sense, the flow computer essentially acts as the cash register in a hydrogen custody transfer application.
The software is used to validate continuously and intelligently, in real-time, field signals and raise an error condition so that appropriate actions are taken when the measurement fails. Depending on the actual root cause, in many cases it can not only detect an error and warn the operator, but it can also semi-automatically or even fully automatically correct for the mismeasurement incident and regenerate the flow calculation results, in near real-time, without adding any further uncertainty. This means that mismeasurement incidents are now resolved in seconds, rather than in weeks, saving vast amounts of time compared to resolving issues manually. This means that paperwork can be filled out swiftly and correctly, removing barriers and complexity from the custody transfer process.
This article was firsts published in the magazine Decarbonisation Technology.