AECOM Process Technologies provides cost-effective removal of sulfur in the mid-size range from 0.2 to 25 tons per day with CrystaSulf®.
Removing sulfur from gas streams that contain 0.2 to 25 long tons per day of sulfur has historically been problematic. In this size range, the operating cost of once-through chemicals for hydrogen sulfide (H2S) scavenging is high, while traditional amine/Claus units suffer from prohibitively high capital costs and operating problems.
CrystaSulf® can remove sulfur economically without the operating issues of aqueous-iron systems and with significantly lower pumping costs for most applications. Using SO2 as an oxidant, CrystaSulf® converts inlet H2S to elemental sulfur through a modified liquid-phase Claus reaction. Elemental sulfur is soluble in CrystaSulf® solution, which eliminates circulating solids in high-pressure equipment. The sulfur is crystallized and separated in equipment designed to handle solids, while the rest of the process remains solids-free.
The CrystaSulf® process can achieve pipeline H2S specifications of less than 4 parts per million by volume (ppmv) at pressures above 150 psig. CO2 has been shown to have no effect on the process. Inlet hydrocarbons also have little or no effect.
- Lower overall treatment cost, especially in high-CO2 applications
- Lower maintenance and clean-out cost
- Greater on-stream factor
- Easy to pump solids-free solution
- Low circulation rate
- No sulfur settling additives or surfactants
- No foaming or plugging problems typically found in aqueous systems
- No special design requirements for slurry handling
- No sulfur solids in circulating solution
- Easy handling, separation, and filtration of sulfur
- Less disposal cost associated with drier sulfur
- Increased buffering capacity (changes happen slowly)
- Easily monitored compound removal
- Modules can be designed for vertical placement (smaller footprint)
- Easy access to all equipment afforded by low-profile design
- Ideal for retrofit in congested plants with space constraint
- Standardized and modular design
- Fast-track schedule to engineer, procure, and construct
- Readily available equipment
- Sour high-pressure natural gas (including shale gas)
- Hydrogen recycle streams in refinery HDS units
- Refinery fuel gas
- Claus tail gas streams
- Gasification syngas
- Off-gas from heavy oil upgrading
- Gas associated with in-situ oil sands operations