“Stripping” the H
2S from water utilizes a gas stream to force the H
2S and Ammonia (NH
3) out of solution and into the gas phase. This stream is processed by a sulfur recovery unit to separate the sulfur from the water,
allowing the water to be re-used as process water, or released to wastewater treatment.
pH Measurement Challenges
Measuring pH in sour water is difficult for most sensor designs. The high temperatures required to convert impurities to the gas phase shorten sensor life. The presence of H
2S can poison and plug most conventional
reference cells. Cyanide and ammonia can poison a reference by forming a complex with the silver ions in the electrolyte. Historically, traditional double junction references would die within a day or less when the sulfide, cyanide, or ammonia levels were very high.