Application: S Zorb sulfur removal technology (S Zorb SRT) was origi-nally developed and commercialized by Phillips Petroleum Co. (now ConocoPhillips Co.) SINOPEC purchased the ownership of the S Zorb sulfur removal suite of technologies in July 2007.
Description: S Zorb SRT is designed to remove sulfur from full-range naphtha, from as high as 2,000 μg/g feed sulfur, to as low as < 10 μg/g product sulfur, in a one-step process with high liquid yield and high octane number retention. S Zorb SRT is different from what is com-monly known as the hydrodesulfurization (HDS) technologies. What dis-tinguishes S ZorbT SRT from the HDS processes includes:
• High octane number retention (especially for reducing > 1,000 μg/g feed sulfur to < 10 μg/g product sulfur in one step)
• Better selectivity and more reactive toward all sulfur-containing species for S Zorb sorbent
• Low net hydrogen consumption, low hydrogen feed purity needed; reformer hydrogen is an acceptable hydrogen source
• Low energy consumption, no pre-splitting of fluid catalytic cracker (FCC) feed stream, full-range naphtha is applicable
• High liquid yield, over 99.7 volume % in most cases
• Renewable sorbent with sustained stable activity to allow synchronization of maintenance schedule with the FCC unit.
Commercial plants: S Zorb SRT has been successfully commercialized in six units. Thirteen units will be commercially operating by the end of 2010.
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H 2 s removal
Application: ELIMINATOR technology consisting of a full line of ELIMI-NATOR products removes hydrogen sulfide (H2S) and light mercaptans from gas streams. Suitable applications are generally sulfur loads be-low 200 lb/d sulfur, and/or as a standby backup unit for other sulfur-removal systems.
Description: The ELIMINATOR technology is extremely versatile, and its performance is not sensitive to operating pressure. In properly designed systems, H2S concentrations of less than 1 ppm can easily be achieved on a continuous basis.
A number of different treatment methodologies may be used to treat sour gas streams.
• Line injection—ELIMINATOR can be sprayed directly into a gas stream with removal of the spent product in a downstream knockout pot.
• Sparge tower—Sour gas is bubbled up through a static volume of ELIMINATOR. A lead-lag vessel arrangement can be installed to allow for the removal of spent solution and the addition of fresh solution without shutting down. This arrangement also results in the optimum utilization of the solution.
• Packed tower—Sour gas is contacted with circulating solution of ELIMINATOR in a counter, packed-bed scrubber.
Products: A full line of ELIMINATOR products can treat any type of gas streams.
Economics: Operating costs are very favorable for removing less than 200 ld/d of H2S.
Installations: Fifteen units in operation.
Licensor: Merichem Company contact
Sour gas
Sweet gas
Drains
Inlet knockout pot
Absorber
Spent scavenger
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H 2 s removal
Application: LOCAT removes H2S from gas streams and produces el-emental sulfur. LOCAT units are in service treating refinery overhead off gas (coking, visbreaking, fluidized-bed catalytic cracking, hydrotreating, hydrofining and hydrodesulfurization), gasification syngas (coal and oth-er organic based matoth-erials), sour-watoth-er-strippoth-er gas, natural gas, amine acid gas (physical solvents: Rectisol, Selexol, Benfield and chemical sol-vents: amines: MEA, DGA, DEA, DIPA and MDEA), Claus tail gas and tank vent gas. Sulfur capacities are typically less than 25 ltpd down to several pounds per day. Key benefits of operation are high (99.9%) H2S removal efficiency, and flexible operation, with virtually 100% turndown capability on both H2S concentration and treated gas volumes. Sulfur is recovered as a slurry, filter cake or high-purity molten sulfur.
Description: The conventional configuration is used to process com-bustible gas and product gas streams. Sour gas contacts the dilute, pro-prietary, catalyst solution in an absorber (1), where the H2S is absorbed and oxidized to solid sulfur. Sweet gas leaves the absorber for down-stream use. The reduced catalyst solution returns to the oxidizer (2), where sparged air reoxidizes the catalyst solution. The catalyst solution is returned to the absorber. Continuous regeneration of the catalyst so-lution allows for very low chemical operating costs.
In the patented autocirculation configuration, the absorber (1) and oxidizer (2) are combined in one vessel, but separated internally by baf-fles. Sparging of the sour gas and regeneration air into the specially designed baffle system creates a series of “gas lift” pumps, eliminating the external circulation pumps. This configuration is ideally suited for treating acid gas and sour-water-stripper gas streams.
In both configurations, sulfur is concentrated in the oxidizer cone and sent to a sulfur filter, which can produce filter cake as high as 85%
sulfur. If desired, the filter cake can be further washed and melted to produce pure molten sulfur.
Operating conditions: Operating pressures range from vacuum condi-tions to 1,000 psi. Operating temperatures range from 40°F to 140°F.
H2S concentrations range from a few ppm to 100%. Sulfur loadings range from a few pounds per day to 25+ tpd. No restrictions on type of gas to be treated; however, some contaminants, may increase operat-ing costs.
Installations: Presently, 204 licensed units, 82 are in operation with 12 additional units currently under construction.
Licensor: Merichem Company contact
1
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H 2 s removal
Applications: SULFUR RITE is a solid-bed scavenger for removal of H2S from aerobic and anaerobic gas streams. Suitable applications are gen-erally sulfur loads below 200 lb/d sulfur, and/or as a standby backup unit for other sulfur-removal systems. The spent media is nonpyrophoric.
Description: Single-bed (shown) or dual “lead-lag” configurations are possible. Sour gas is saturated prior to entering media bed. Gas enters vessel top, flows over media where H2S is removed and reacted. Sweet gas exits the bottom of vessel. In the single-vessel configuration, when the H2S level exceeds the level allowed, the vessel must be bypassed, media removed through the lower manway, fresh media installed and vessel returned to service.
For continuous operation, a dual “lead-lag” configuration is desir-able. The two vessels operate in series, with one vessel in the lead posi-tion, the other in the lag position. When the H2S level at the outlet of the lead vessel equals the inlet H2S level (the media is completely spent), the gas flow is changed and the vessels reverse rolls, so that the “lag”
vessel becomes the “lead” vessel. The vessel with the spent media is bypassed. The media is replaced, and the vessel with fresh media is re-turned to service in the “lag” position.
Operating conditions: Gas streams up to 400°F can be treated. Gas streams should be at least 50% water saturated.
Installations: Sixteen units installed.
Licensor: Merichem Company contact
Sour gas H2O inject
Sweet gas Drains
Inlet knockout pot
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