Measurement of dissolved H2S, (hydrogen sulphide), in difficult applications such as tanneries, circuit board waste and waste water treatment - Dr Michael Strahand

ATi has developed a new dissolved hydrogen sulphide monitor that for the first time enables you to measure levels of H2S in difficult applications.

Measurement and control of H2S levels after pre-treatment is vital because the presence of even low levels of H2S will have a detrimental impact on subsequent biological treatment processes. Measurement at the discharge point is important to ensure compliance with legal requirements.

PCB manufacture

Hydrogen Sulphide gas is used to treat exhaust etching solutions from PCB industries, containing high level of Copper under Ammoniacal complex form. The gas is used to precipitate Copper Sulphide. The sulphide level must be always in a small excess (few ppm, usually 5 - 10) in order to be sure that all Copper is precipitated. Measurement of dissolved sulphide would allow control of the process.

The waste water from this process also needs to be processed to remove dissolved sulphides