To maintain profitability, refineries are being forced to refine more sour crude, which is less expensive than sweet sulfur free crude.
The sulfur recovery unit (SRU) capacity dictates what types and volumes of sour crude feed stocks can be processed. A small gain in capacity in the SRU can yield significant profit for the refinery, so maintaining throughput while ensuring availability and safety is key.
It is imperative that the sulfur present in sour crude be removed on the front end of the refining process; as sulfur bearing crude is corrosive and will produce hydrogen sulfide (H2S) that will cause stress corrosion cracking throughout the balance of plant. The sulfur captured in the sulfur recovery unit is a bi-product of the process and can be sold or blended to manufacture sulfuric acid.