The oil and gas industry is challenged with the development of alternative technologies to control hazardous and regulated emissions. Federal and state agencies have emphasized an effort to minimize flare usage as a control device. The direct impact of regulatory action is on the shoulders of those responsible for the planning, execution and management of unit operations associated with planned maintenance and turnaround activities. The interest of these stakeholder groups is due to potential schedule interruptions caused by lack of flare capacity or downtime during critical phases of the turnarounds, which can lead to additional costs and lost production.
As such, refineries are looking for alternative technologies to flares that can provide flexibility during various operations and maintenance activities. During unit shutdowns and turnarounds, there may be periods when the refinery flare gas recovery system capacity can be challenged. The Vapor Point Scrubber system was developed to ensure compliance with permit limits for H2S and SO2 emissions by scrubbing sour flare gases. Vapor Point's processes aid the refining market in meeting the new compliance requirements while maintaining operational efficiencies.
Vapor Point applies high-efficiency liquid scrubbing systems to remove VOCs, H2S and other hazardous air pollutants (HAP) during different phases of unit decontamination. Specially designed temporary vessels for liquid and vapor phase product management have also been developed and are key elements in some applications. The vapor phase emission control systems and specially designed code process vessels have met the needs of the refining industry with numerous field implementations.
A major Gulf Coast oil refiner and Vapor Point recently worked in conjunction on a project to develop a temporary system to meet the turnaround schedule requirements and process restrictions to reduce H2S loading to the plant flare system during unit shutdown and decontamination. The high efficiency of these liquid scrubber systems and the ability to target the H2S contaminant streams were ideal to configure, engineer and design in the turnaround application. Safety, process controls and turnaround schedule compliance were the utmost priorities in the design and field implementation.
During the shutdown process prior to a turnaround, there are some periods when the flare gas venting needs could exceed the flare gas recovery system capacity, which would require a slowing of the shutdown process and prolong the shutdown. The refiner opted to use a scrubber system to remove percent levels of H2S from flare gases during its hydrotreater unit shutdown and decontamination. Vapor Point engineered a solution to remove H2S compounds from the refiner's flare gas. A continuous emission monitoring system (CEMS) was used to measure emissions. The flare line, which is 36 inches in diameter, was projected to output 7.2 MMSCFD, with a concentration of H2S higher than 10,000 ppm. Vapor Point engineered a temporary system designed to remove H2S from any flare gas that bypassed the flare gas recovery system and reduced the H2S content to below permitted limits. After verification from the local CEMS, the scrubbed gas was routed to the flare.
The project resulted in maintaining H2S levels below 120 ppm through the entire deinventory process. Additionally, the operation allowed for the completion of the decontamination of the unit on schedule with no delays due to the system provided by Vapor Point.
For more information, visit www.Vaporpoint.net or call (800) 207-0065.
