Sulfur recovery in the oil & gas industry

The Claus process is the most widely used gas desulfurizing process, removing the hydrogen sulfide (a poisonous gas) from the refinery sour gases and producing elemental sulfur as a valuable by-product.

The refinery gases, including those from the atmospheric distillation column, plus other sour gases are separated into fuel gas and hydrogen sulfide in the Amine treatment stage. Then in the Claus process, the hydrogen sulfide is mixed with air in the correct proportions, and passed through a reaction furnace, where the gases react at the very high temperature – over 850°C. In a condenser stage hot liquid sulfur is extracted, and the process is repeated on the remaining gas.

The sulfur discharge is monitored and controlled using a molten sulfur flowmeter with an integrated heating jacket: flow and temperature control is important as if the sulfur temperature rises too much, the viscosity increases due to the formation of polymers. KROHNE offers an ultrasonic flowmeter with an integral heating jacket for this application. Other Claus sulfur recovery process instrumentation available from KROHNE includes vortex flowmeters for balancing the gas and steam flows, and electromagnetic flowmeters for controlling the condenser water flows.