Beside quantity measurement, metering systems often require quality measurement of the products. For quality measurement, (automatic) sampling and analyser systems are used to accurately determine the quality of the oil or gas. Automatic or manual sampling systems are used to collect representative samples to be analyzed in a laboratory. Online analyser systems can be in-line fluid analysers up to fully integrated analyzer houses including chromatographs, H2S analysers, CO2 analysers, water in gas monitors, hydrocarbon and H2O dew point analyzers etc. As an integral part of the Custody Metering Package, ODS Metering Systems designs, engineers, procures, tests and delivers sampling and analyser systems as a loose skid or integrated on the metering skid. All our sampling systems are designed in accordance with the applicable ISO, API, IP and ASTM standards.
Insert Automatic Grab Sampling
Insert type flow-proportional grab sampling systems are the most cost effective sampling systems. Especially for systems in intermittent operation, insert type sampling systems are the ideal choice as maintenance can be done in between shifts. A sample extractor is installed in the main line to capture the sample from the flow and discharge it by positive displacement through a downward gradient small-bore pipe (to prevent water traps) into a sample receiver mounted in a housing. The receiver housing can contain multiple receivers with manual or automatic changeover. The flow proportional control can be integrated within the Metering Control System.
Fast Loop Sampling
Fast-Loop Sampling Systems are often used when measurement systems are in 24×7 continuous operation, such as pipeline metering systems. In contrary to an insert type grab sampler, the fast loop by-pass sampling system can be maintained and commissioned without interrupting the measurement and analysis. Another advantage is that process analysers can be integrated in the fast loop for real time BS&W (water-cut) analysis, densitometers and other on-line measurement devices. Representative samples of the fluid can only be guaranteed when there is sufficiently mixing by the velocity of the fluid. Sometimes additional mixing with a pump or static mixer is required, based on the process conditions. The sample extractor works flow proportional and the functionality can fully be integrated in the Metering Control System. ODS is expert in quantity and quality measurement and offer the best suitable sampling solution for your application.
Gas Sampling and Analysing
Nowadays, the value of natural gas is not only determined by the volume flow or mass flow quantity, but the gas is transferred in total energy in caloric value. To calculate the caloric value, the gas hydrocarbon composition has to be analysed. Online hydrocarbon composition analysis can be done using a gas chromatograph. Adjacent to the online analysis, a manual or automatic sampling system can take samples from the gas for further analysis in a laboratory. Besides hydrocarbon composition analysis for energy calculation, operators are often interested to know further details of the gas such as the H2S, CO2 or H2O content as well as HC dew point for real time process control. To perform high-quality analysis it is crucial that the analysers receive an uncontaminated gas sample achieved through sample conditioning. The full sampling and analyser system can be built in a rack, cabinet or analyser house. Depending on the environment, the shelters are supplied with heaters, HVAC, fire and gas protection etc. As part of the metering package, ODS Metering Systems offer total analyser solutions in line with your specific requirements.