ISO TR 14749:2016 pdf free
ISO TR 14749:2016 pdf free.Natural gas一Online gas chromatograph for upstream area
The GC is a technique for separating and analysing compounds that can be vaporized without decomposition in a continuous and automatic manner of sample injection, separation, data integration and reporting. A precise volume of sample gas is injected into the column which contains a stationary phase (packing) that is either an active solid (adsorption partition) or an inert solid support that is coated with a liquid phase (absorption partitioning). The gas is moved through the column by means of a mobile phase (carrier gas). Selective retention of the components of the sample takes place in the column and causes each component to move through the column at a different rate. This action separates the sample into its gaseous constituents.
A detector detects the elution of component from the column and produces electrical outputs proportional to the concentration of each component. Output from the detector are amplified in the electronics, then transmitted to the controller for further processing.
Output from the controller is normally linked to flow computer, DCS, remote personal computer (PC) or a printer. Connection between the GC Controller and others can be accomplished via a direct serial link or Ethernet link.
The GC today has features to report alarm and ignore any fault (report last good value) and also provides good diagnostic and troubleshooting data. To verify the GC performance, repeatability check with Standard gas and baseline check are recommended.
The nature of gas processing in upstream petroleum industry is relied on gas separation and gas dehydration units. There is potential of small liquid droplets in Natural Gas which are able to get into GC causing lots of problems such as incorrect data, failure of GC, etc.
Sample probes and sample conditioning unit have to be properly designed and installed to address liquid carry over and condensing issues. A well designed, installed and maintained sampling system is vital to ensure the provision of a representative sample for GC analysis.
The purpose of the sample handling system is not to transfer an exact sample of the process fluid to the GC. Rather, the purpose is to transfer a representative sample of the fluid after it has been conditioned that is compatible with GC sample requirements.ISO TR 14749 pdf free download.
