Detecting Sulphur Compound Impurities in Natural Gas, LPG, Propane and Butane

The MEDOR® Exp from Chromatotec® is aimed at online monitoring of sulphur compounds in hazardous zones. This analyser offers continuous analysis and full speciation of all naturally occurring sulphur compounds such as H2S, Methyl and Ethyl Mercaptan as well as odourant blends, from concentrations as low as 1 ppb.

The system uses proven auto-GC technology for odourisation, quality and safety applications in a wide variety of processes:

Odourisation application: The MEDOR Exp has been developed to monitor all available odourant and mercaptan blends available from all manufacturers. The system can be used to continually analyse and control odourant injection systems for natural and biogas sites.

Pipeline quality control: The analyser is widely used for sulphur content in natural gas storage and transport. Odourless gas can be analysed for natural sulphur species before and during transport or storage.

Process monitoring – gas cleaning & desulphurisation: Sulphur removal processes, such as biogas treatment before injection into a pipeline network, requires careful monitoring and control. With detection limits as low as 1 ppb H2S, the MEDOR Exp system offers users unparalleled security for process monitoring.

The quality and performance of the system has been recognised worldwide by Standard Organisations such as ISO and ASTM. The MEDOR Exp is supplied in a stainless steel purged cabinet. The system is certified ATEX zone 1 and 2, group IIC T4 and CSA (Class 1 Division 2). for hazardous areas.

The Exp cabinet is protected by continuous flow with an X or Z purge system certified for zone 1 and zone 2 respectively. This purging system includes pressure regulator with a flow restrictor to control the inlet dilution. A flow controller is located at the valve outlet to validate the flow out of the cabinet. The cabinet is pressurised and diluted continuously.

IP 66 class allows the use of the unit in waterproof case environment and reduces the instrument air consumption volume needed for the continuous dilution. H2S, mercaptans and total sulfur can be analysed by MEDOR Exp with only nitrogen used for analysis and integrated calibration device.

One of the main advantages of MEDOR is that no additional hazardous area is created in the analyser as it could be the case with hydrogen or air presence and a flame. The worst case is taken into account to calculate the dilution flow to stay under the explosive condition.

If pressure inside the cabinet is not higher than the ambient pressure, the power is switched off by the X-purge system. For service there is a by-pass key to open the cabinet without pressure inside.

Due to these improvements, Chromatotec provides a full analytical solution for natural gas monitoring in hazardous area.