What is the SULFATREAT process?

The SULFATREAT process is a chemical reaction that removes the hydrogen sulfide from a gas stream via specially designed reactant products. The apparatus consists of a fixed-bed or batch-type granular hydrogen sulfide reactant contained in a pressure vessel. The reactant in this case is one of the SULFATREAT or SUFLATREAT SELECT products, and the vessel - provided it is engineered to treatment specifications - can be obtained from a variety of sources, including the customer’s inventory. Both the unused and spent product are safe and stable.

During the process, sour gas or vapor flows through the consistently sized and shaped granular SULFATREAT product in the bed, where the hydrogen sulfide reacts with the product to form a stable and safe byproduct. The SULFATREAT process’ advantage is that product consumption is dependent only on the amount of hydrogen sulfide that passes through the bed. This economically matches the need for H2S removal with variations in system flow conditions and outlet specifications, regardless of the total volume or other common components of the gas.

The flexibility of the SULFATREAT process allows the system to adapt to variations in H2S outlet specifications that may result from changes in operating preferences or tighter regulations, often without additional capital equipment or system retrofitting. Predictable pressure drops, long bed life, easy and safe handling, and a simple reliable operation are a few of the features of the SULFATREAT process.

What Equipment is Required?

SULFATREAT SELECT products will work in any water content range from dehydrated to water saturated gas.

Our SULFATREAT range, however, requires the gas to be water saturated. In some cases it may be necessary for a water injection system to be installed to ensure this condition is satisfied.

Just upstream of the SULFATREAT* vessel(s), the installation requires a small inlet separator to remove excess liquids from the gas. Care should be taken to insulate the lines and SULFATREAT vessel(s) to prevent a temperature drop of no more than 5° F after the last liquid separator across the outlet of the SULFATREAT vessel.

The actual design of the SULFATREAT vessel(s) can be customized to specific site needs based on inlet gas flow, operating pressure, desired pressure drop, and the days-to-outlet-H2S specification. Low predictable pressure drops, as low as a few inches of water, allow a wide range of reliable applications and equipment configurations. Properly constructed SULFATREAT vessels should last 20 years or more.

Equipment Arrangements - Single Vessel

The most basic design is a single vessel where the inlet H2S concentration is reduced at the outlet to “non-detect” at the beginning of the bed life, gradually increasing to an outlet specification. Temporary bypass of the vessel or interruption of gas flow is necessary for the short time it takes to replace the SULFATREAT* material. The main advantage of this type of system is that the capital costs are minimized.

Equipment Arrangements - Lead/Lag Vessels

There are two benefits of this vessel configuration. The first is that it allows for change outs of the spent media without interrupting the processing of the gas stream. In addition, there will be an improvement in the overall efficiency of the system that can be as high as 20%. This arrangement is feasible where the quantities of H2S increase and for systems operating with sufficient working pressure.

Two vessels are arranged in series, flowing gas through the first bed into the second. The lead vessel acts as the “working” unit to remove all of the H2S at the beginning of a treatment period, with its outlet H2S increasing over time. The gas can go to the second, or “lag” vessel for further polishing, or it can bypass the second vessel up to the desired gas H2S outlet specification. The operation of the lead bed is similar to the single-vessel arrangement. The second vessel can be placed in operation at startup, or it can be used to polish the H2S remaining in the gas from the lead vessel when the level of outlet H2S reaches the maximum specification.