Charles L. Kimtantas - Bechtel Hydrocarbon Technology Solutions, Inc.
Sulfur emissions from refineries are very important and regulated by the federal and state governments. One source of sulfur emissions from the refinery are the sulfur pits and sulfur tanks that store liquid sulfur produced in the Claus sulfur recovery unit. These vents can contain hydrogen sulfide, sulfur dioxide, and elemental sulfur. At one time these vents were discharged directly to the atmosphere. However, because of the hydrogen sulfur and sulfur dioxide content, safety concerns and in some cases government regulation, these vents are collected and routed to the sulfur unit thermal oxidizer for combustion to sulfur dioxide and discharge to the atmosphere.
Refinery sulfur emissions are being forced to lower and lower levels by governmental regulators. This is especially true whenever a refinery wants to make changes or additions to the refinery. Refineries are always looking for ways to reduce sulfur emissions in one area of the refinery to allow flexibility in operations (crude slate) and changes in configuration (add equipment or units). The sulfur pit and sulfur tank vents are a source of sulfur emissions that offer opportunities to control and reduce the sulfur emissions from the sulfur plant. Some refineries have changed the routing of these vents from the thermal oxidizer to the front of the Claus sulfur recovery unit, where the sulfur is recovered, and some have routed the vents to caustic or other scrubbing systems to remove the sulfur. This paper will discuss the various disposal options for the vents and look at the pros and cons of each option.
Technical Advisor: Ron Pitman (Motiva Enterprises)