Since 2005, Gulf Coast Environmental Systems (GCES) has provided sulfur reduction plants with the treatment solutions to treat H2S and CS2 Pollutants and other Greenhouse Gas (GHS) emissions. Through a thorough review of multiple sulfur reduction plants sulfur abatement needs GCES developed a state of the art Regenerative Thermal Oxidizer (RTO) system to improve fuel efficiencies, reduce operating costs and minimize NOx production that would come from operation of a standard Direct-Fired Thermal Oxidizer (TO).
In handling each and every project, GCES carefully considers the make-up of the process stream as given by the customer. One of the most important factors with every application is to properly understand the flammability nature of the vent stream and to design a solution with safety as the number #1 priority.
Safety Considerations for Sulfur Abatement via Thermal Oxidation
Carbon Disulfide (CS2) is a colorless compound with an ‘ether-like’ odor. It is highly flammable with a Lower Explosive Limit (LEL) of 1.3% by volume, meaning 1.3% of the total volume of air consists of Carbon Disulfide. If the atmosphere has less than 1.3% by volume Carbon Disulfide, an explosion cannot occur even if a source of ignition is present. When the CS2 concentration reaches 1.3% by volume an explosion can occur if there is an ignition source.
Hydrogen Sulfide (H2S) is a colorless, very poisonous, flammable gas with a foul odor characteristically similar to rotten eggs. It is less explosive than Carbon Disulfide with a LEL value of 4.0% by volume. The atmosphere would require more than 4.0% of its volume to contain H2S to allow the possibility of an explosion with the presence of an ignition source.
Let’s assume (for this example) the maximum stated carbon disulfide amount in an 80,000 Nm3/hr vent stream is 301 kg/hr. This could include up to 116 kg/hr of H2S also. This combination gives a combined weighted LEL value of 1.89% by volume. The LEL level of this process stream is about 0.21% by volume, or 11% of the LEL value – at the stated extreme conditions. At this level we still have approximately a 10 fold increased safety factor before approaching explosive conditions. GCES carefully designed equipment to treat this process stream with detailed attention to safety and risk potential. As a result for over a decade our systems have safely convert the CS2 and H2S to SO2 and SO3. In many cases our customers have choses optional post treatment with a quench and scrubber which can remove the SO2 and SO3 from the tail-end of the GCES Thermal Oxidizer system.
As stated by one of GCES’s biggest competitors to a potential customer requiring a sulfur abatement solution, ‘You should call Gulf Coast Environmental Systems for this project. They have developed the expertise for this very difficult application.’
GCES is considered worldwide one of the most diligent and experienced application companies in the air pollution control market. GCES excels in situations such as this one, with unique applications that had not been previously completed by our competitors by implementing the proper thermal oxidizer technology for the application and developing custom systems that are not only effective but also efficient and safe to operate.