Hydrogen Sulfide is a chemical compound with the molecular formula H2S . H2S is a colorless toxic gas with an extreme rotten egg odor. Humans can normally detect the odor of the compound at 0.0047 ppm. A single breath at 1000 ppm is lethal. The need to control or remove hydrogen sulfide to safe levels is necessary in all types of industries and applications, but is particularly necessary for the hydrocarbon processing industry. In addition to the safety concerns for plant personnel and operators, there are also corrosion concerns with H2S because it is highly corrosive and can cause damage to pipelines, equipment and downstream processes.
Hydrogen sulfide removal processes can be classified according to the amount of sulfur to be removed per day (lbs of sulfur from H2S per day). As a general rule, low tonnage sulfur removal of up to 1,000 lbs per day should consider the use of an H2S scavenger. A requirement that exceeds this general level of sulfur would consider other processes capable of handling larger quantities of sulfur such as amine, caustic, or direct oxidation.
H2S scavengers are classified as either (1) fixed-bed adsorbents or (2) liquid scavengers. Both types are treatment options for low temperature H2S reduction from sour hydrocarbon streams. Both adsorbents and liquid type scavengers have been used successfully for many years.
Liquid scavengers are typically supplied in drums or totes, and work by pumping the scavenger liquid directly into the sour gas pipeline. When the liquid scavenger runs out, the empty drum must be replaced with fresh chemical. One of the disadvantages of this type of chemical can be high treating cost. Without specialized equipment, operating costs can run as much as 10 times that of fixed-bed adsorbent systems. Another drawback of using liquid scavengers for H2S removal is that it has been proven to form solids that deposit in pipelines, valves and tanks leading to additional costs and headaches for downstream processors.
Conversely, a fixed-bed H2S removal system such as our proprietary SULFURTRAP® , offers lower treating costs, doesn’t form by-products or side reactions, and becomes a safe non-hazardous waste that is typically disposed at a landfill. It is a safe, simple and clean process for selective H2S removal. Fixed-bed hydrogen sulfide removal systems work by passing the sour gas stream through the fixed-bed of solid media in a vertical vessel. Fixed-bed systems such as SULFURTRAP® can handle fluctuations in flow rate and H2S concentration with no decrease in performance or efficiency. SULFURTRAP® is supplied in 2000 lb bags, 500 lb drums or 50 lb drums.
SULFURTRAP® represents the next generation in fixed-bed hydrogen sulfide removal technology. It easily removes H2S to <1 ppm, is capable of high sulfur loading capacity and is free-flowing in its reacted form for easy product change-outs.