Duty: To measure the concentration of H₂S in a process liquid stream, including the measurement of H₂S in crude oil.

The principle of operation is as follows. The Analyser consists of a stripping system coupled with a NovaSulf H₂S Analyser. The liquid sample enters the top of an insulated, heated sample handling cabinet via a flow controller to maintain a constant sample flow. Nitrogen flows down a vertical tube to a sintered plug located within the liquid and then flows up through the liquid. As the nitrogen mixes with the liquid hydrocarbons it strips out the dissolved H₂S in the liquid.  

The degassed liquid falls into a reservoir and then to the drain. At the same time, the nitrogen containing H₂S in proportion to that in the original liquid is piped directly to the NovaSulf^TM HG 400 series H₂S Analyser to be measured.

The benefits of this technology can be summarised as follows:

• As the measurement is specific to H₂S, there will be no interference from other sulphur components
• A continuous analyser, not cyclic
• The instrument has a wide range capability, measuring between 0-2ppm to 0-1% H₂S
• Configuration of the system is via a touch screen which eliminates the need to open the enclosure.
• Single point calibration results in lower running costs
• A compact flash card allows for remote evaluation and diagnostics
• Capital investment is minimised as up to four detection modules can be run from one controller
• Suitable for gas group IIC environments.

With its wide-ranging ability to measure H₂S from % levels down to ppb levels, the HG400 range of H₂S process analysers can be utilised in many process industries, including the measurement of dissolved H₂S in crude oil