UOP NGL recovery solutions offer the technology and expertise to solve your gas challenges.
Take advantage of our portfolio of NGL recovery solutions to ensure your projects maximize the recovery of high value NGL products at low production costs and downtime — even in remote areas.
Our modularized packaged plant solution deliver faster on-stream time, lower installed cost and high feed gas flexibility. Sophisticated engineering and modularization techniques combined with a modularized project strategy offer:
Reduced construction rework
Greater safety assurance
Reduced security risk
Access to skilled and reliable labor
Fast execution
Competitive costs
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UOP-Twister® Supersonic Gas Separation System
Provides partial NGL recovery with minimal footprint, no chemical consumption, and no maintenance or inspection required.
UOP Modular Equipment
Increase recovery of valuable NGLs through a pre-engineered approach with UOP Russell cryogenic turbo expander, mechanical refrigeration, JT plants and adsorption systems. Modular designs help get your plant up and running faster than a custom-built solution, getting you to revenue more quickly.
Ortloff Engineers, Ltd. Alliance
Increase recovery of high-value ethane, propane and heavier hydrocarbon components while saving power consumption costs through a cooperative alliance between UOP and Ortloff Engineers. See higher profits and the flexibility to respond to varying economic conditions.
Even at low levels, mercury in natural gas poses a threat to the structural integrity of your equipment. UOP adsorbent solutions
help provide total mercury sequestration from natural gas, LPG and other light hydrocarbon streams.
Advanced Mercury Removal (Hydrocarbon Processing, Jan 2010)
Image may be NSFW. Clik here to view.Regenerable UOP HgSIV™ Adsorbents
Silver loaded molecular sieves specifically formulated to remove mercury and regenerate with a clean gas stream. Can be loaded into an existing molecular sieve dehydration unit to simultaneously remove mercury, water and other impurities.
Find out more: Contact us
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Non-regenerable UOP Guard Bed (GB) Adsorbents
Silver loaded molecular sieves specifically formulated to remove mercury and regenerated with a clean gas stream. Can be loaded into an existing molecular sieve dehydration unit to simultaneously remove mercury, water and other impurities.
The switch from diesel to Liquefied Natural Gas (LNG) is a smart choice. Through our alliance with Black & Veatch, we offer full turnkey, modular, small-scale natural gas pre-treatment and liquefaction plants between 50 and 500 gallons per day production capacity. By working with a cost effective and reliable liquefaction provider, UOP modular Small Scale LNG plants offer long-term value and lower lifecycle costs.
“Virtual pipelines” for capturing stranded gas and flare gas
Power generation
Gas storage for peak shaving
Producing a substitution fuel for diesel for long-haul trucking, and marine, railroads, mining, or drilling/fracking applications (i.e. any high horse power engines).
Small Scale LNG. Big Dividends.
Fast LNG production through the standard modular approach
Innovative Acid Gas Removal in the Gasification Value Chain
The SeparALL™ process helps meet the needs of clean power generation through integrated gasification combined cycle (IGCC) power generation or can be used in the gasification value chain to produce chemicals and syn fuels.
Sulfur removal with separate CO2 removal and capture
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UOP SeparALL Process
Using a physical solvent, the SeparALL process efficiently removes harmful acid gas from synthesis gas streams to help you meet product specifications, protect downstream processing equipment and comply with environmental regulation. Used exclusively in Syngas applications.
PSA Polybed
For hydrogen recovery/purification applications where the feed stream is at low-to-intermediate pressure (<1000 psig) and where downstream process requirements require minimum pressure reduction and high purity hydrogen product.
PSA Polysep
Offers a range of separation characteristics (permeability, selectivity, and contaminant resistance) to allow the design of an optimum system to fit a given process need.
In the hundred years since UOP was founded, the world’s population has quadrupled while world GDP has grown by more than 700 percent, adjusted for inflation. This incredible growth was fueled by the oil and gas industry, led in many cases by technology from UOP.
UOP was founded in 1914 to commercialize 12 inventions held by Jesse Adams Dubbs. Descended from a Dutch family of chemists, and born in Pennsylvania oil country, Jesse Dubbs fell naturally into the oil business. Such was his confidence in oil that he named his eldest son Carbon. After joining his father in business, Carbon added the middle initial P to make his name “euphonious,” he said. People started calling him “Petroleum” for fun and, finding cache in the name, he did little to correct them.
One of the Dubbs inventions was developed in 1909 to demulsify oil, specifically to yield heavier fuel oil and asphalt. The byproduct was lots and lots of gasoline – a 30-percent yield, four times greater than conventional refining methods. When the younger Dubbs brought this to the attention of the Chicago meat packer J. Ogden Armour, the invention was reviewed by Armour’s patent attorney Frank Belknap.
Belknap reasoned that, if the 1909 Dubbs process could be patented, it would take precedence over a 1912 patent for a similar process granted to William Merrion Burton of the Standard Oil Company of Indiana. With this patent, Armour could demand payments from Standard Oil – and gain retribution against his rival John D. Rockefeller, that company’s principal shareholder.
After acquiring the rights to Dubbs’ invention, Armour created the National Hydrocarbon Company on July 17, 1914. Belknap resubmitted the patent application, which was granted on January 5, 1915. The company immediately began preparing legal complaints, and the first of these was filed on August 7, 1916.
On Oct. 3, 2005, Honeywell announced its acquisition of Dow’s 50-percent stake in UOP, closing the deal on Nov. 30 for $825 million, making UOP a wholly-owned subsidiary of Honeywell, and part of its Performance Materials and Technology business unit. Almost immediately, Honeywell began new investments in UOP’s research and development capabilities and funding major development projects.
Cleaner fuels and renewable energy became primary targets for research. In March or 2006 UOP entered into an alliance with Albemarle Corporation, a leading supplier of hydrotreating catalysts and technologies, to help refiners make cleaner fuels.
In 2006, UOP developed Honeywell Green Diesel™ technology, a fuel chemically identical to petroleum diesel, but made from inedible plants and waste oils. This was followed by contracts for the Methanol-to-Olefins (MTO) process to make plastics from coal and natural gas, the Uniflex™ process to convert heavy oil residuum into valuable fuels, and Honeywell Green Jet Fuel™ — an aircraft fuel made from renewable sources.
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In 2012, UOP acquired 70 percent of the Thomas Russell Company, a leader in modular plants for the natural gas industry, to form UOP Russell. Also that year, the company added Callidus Technologies, a manufacturer of combustion equipment including process heaters, burners, flares and other equipment.
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By this time, a revolution in natural gas was well underway, with cost-effective ways to retrieve it from shale formations, remote locations and even off-shore. UOP’s Separex™ Membrane Systems and other technologies clean natural gas so it can be sent through pipelines and processed into LNG, moving from places with abundant supplies to new markets where gas is in high demand. Once marginal or inaccessible sources of gas are now highly productive fields, making natural gas a cost-effective source of fuel, power and petrochemical compounds.
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UOP celebrated its 100th anniversary in 2014 with a series of customer recognition events and employee celebrations, and surpassing $3 billion in revenue for the first time.
Today, UOP is a worldwide organization with more than 5,000 people working in 30 offices and plants located in 19 countries. UOP continues to invest in research and development, operating the world’s leading centers of research for the catalytic processing of hydrocarbons. Scientists and engineers from around the world are inventing better ways to convert oil, natural gas, coal and biomass into the fuels and chemicals required to support the growth and well-being of our world, while keeping the air and water we depend on clean.
A full-fledged conglomerate by 1975, diversification had rendered UOP a slow-growth company, consisting of the Process Division that encompassed its traditional petroleum business – and the Construction, Water, Air Correction and Chemical Divisions. On May 1 that year, The Signal Companies acquired a 50.1-percent majority ownership of the company, and raised its ownership to 100 percent in 1979. That same year, UOP expanded its expertise to natural gas processing with the acquisition of Separex.
UOP continued to operate relatively autonomously until 1983, when Signal dispatched a management team to improve profitability at UOP. Within two years, this team had closed or sold every business not related to oil and gas, returning UOP to its core business.
Signal itself merged with Allied Chemical Corporation on Aug. 6, 1985, creating a formidable competitor in the petrochemical and aerospace markets. At that time, UOP became part of AlliedSignal’s Engineered Materials division.
On Aug. 22, 1988, UOP merged with its longtime rival and collaborator, the Catalyst, Adsorbents and Process Systems (CAPS) division of Union Carbide. The new company – renamed UOP LLC – combined CAPS’s expertise in synthetic molecular sieves with UOP’s expertise in process technology and licensing. As a result of the merger, UOP was now co-owned by AlliedSignal and Union Carbide.
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UOP introduced the Oleflex™ process in 1990, an improved process to manufacture gasoline components and building blocks of plastic from propane and isobutene.
In 1995, UOP acquired the Process Technology Licensing business of Unocal. This combined UOP’s leadership in catalytic reforming and catalytic cracking with Unocal’s expertise in hydroprocessing. Also that year, the Riverside facility was recognized as a National Historic Chemical Landmark by the American Chemical Society.
In 1999, AlliedSignal – by now one of the leading technology and manufacturing companies in the world — announced a $13.8-billion acquisition of Honeywell, combining AlliedSignal’s position in aircraft equipment with Honeywell’s aircraft control and aerospace operations. When the deal closed on Dec. 2 of that year, the new company adopted the Honeywell name for its strong brand recognition.
Also that year, Dow Chemical Company announced plans to acquire Union Carbide, closing the $11.6 billion merger on Feb. 5, 2001. As a result, in little more than a year, UOP went from being jointly owned by AlliedSignal and Union Carbide to being jointly owned by Honeywell and Dow.
In 2003, UOP was awarded the U.S. National Medal of Technology for its history “of sustained leadership and innovation for the worldwide petroleum and petrochemical industries.”
Entering the 1970s, UOP became involved in several environmental technologies. The introduction of CCR Platforming™ led to lead-free gasoline, and this was followed by the catalytic converter — both removing millions of tons of pollutants from the air every year. UOP also created the basis for biodegradable detergents using linear alkylbenzene (LAB), eliminating the foaming that had become common on rivers and lakes.
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To promote lead-free gasoline during the 1970s, UOP sponsored Can-Am and Formula One teams developed by Don Nichols’ Shadow Racing team. Race fans were drawn to the team’s innovative designs, underdog status and black livery featuring a caped figure in silhouette. The Shadow racers also used UOP lead-free gasoline as a fuel, promoting the technology with every win, and proving the superiority of the fuel to conventional leaded gas.
Following President Nixon’s trip to China in 1972, UOP was invited to advise Chinese enterprises on petrochemical technologies for synthetic fibers in an effort to convert cotton fields to food production. For UOP, this marked the resumption of a decades-long relationship, returning to a country where Dubbs cracking units had been operating for nearly half a century. Due to these and other technological developments, UOP began to promote itself in advertising as “The Answer Company.”
When oil prices rose in 1973 and 1974, the industry made advancements in exploration and recovery, and UOP began a drive to expand yields from a wider range of crudes. The amount of transportation fuel that could be derived from a barrel of oil had grown steadily since the days of Clean Circulation, punctuated by UOP’s work on FCC, alkylation, the Platforming process, hydrocracking, and finally in 1971, the CCR Platforming™ process.
UOP generated so much income that it threatened the American Chemical Society’s non-profit status. Seeking to resolve this while diversifying its source of income, the ACS sold UOP to shareholders in a 1959 public offering.
Within a year, shareholders were pining for UOP to diversify its operations and insulate the company from the boom-and-bust cycles in the petroleum industry. By 1966, UOP had acquired more than 20 businesses in trades as diverse as fragrances, food additives, copper mining, forestry and even manufacturing truck seats and aircraft galleys.
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In Japan, UOP established a manufacturing and licensing company with Japan Gasoline Company in 1963 called Nikki-Universal. Five years later, the Union Showa company (USKK) was created by Showa Denko and a Union Carbide division that later joined UOP, to manufacture molecular sieves.
UOP introduced the revolutionary Parex™ process in 1970, enabling efficient production of high-quality paraxylene for polyester, resins and films.
Having lost half of its engineers, surviving on a slim diet of engineering projects and with few prospects, UOP recruited the affable president of the Arkansas Natural Gas Corporation David W. Harris to run the company. Harris proved to be an exceptional diplomat, holding plaintiffs at bay while negotiating a handful of new deals to keep the company afloat.
These few years were critical because, in 1947 a protégé of Ipatieff named Vladimir Haensel perfected a revolutionary new method of catalysis that used platinum as a reforming agent. The use of a metal more precious than gold to break down crude oil was thought to be economically impossible. But the method, called the Platforming™ process, greatly multiplied the yields of high-octane gasoline from crude oil while producing hydrogen for purifying — or “hydrotreating” — refinery feedstocks. This invention became the world’s leading process for making gasoline and it gave UOP a new and highly profitable process to replenish its licensing income.
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This and other UOP technologies helped to launch the petrochemicals industry during the 1950s. In addition to making fuels, refineries could now turn out new compounds of benzene, toluene and mixed xylenes that provided the building blocks for nylon, polyester, styrene and other plastics.
These products had numerous industrial uses as films, packaging and construction materials, in precision instruments and life-saving medical applications, as well as house wares and toys. Petrochemical technologies developed by or in conjunction with UOP gave birth to new manufacturing industries that employed millions more people, fueling an economic expansion that transformed entire nations into export-led economies.
In fact, dozens of new countries gained independence in the postwar period – among them, India, Indonesia, The Philippines, South Korea, and many more in Africa and the Middle East. With independence came the need to develop domestic sources of fuel and power as well as manufacturing.
Already a world traveler, UOP added many new destinations to its collective passport. UOP relocated its headquarters to Des Plaines, Ill. in 1952 to gain closer proximity to the new airport, O’Hare Field, which was then under construction. UOP also entered manufacturing, establishing its first facility in Shreveport, La.
In 1933, Ipatieff introduced solid phosphoric acid as a catalyst to stimulate even higher yields of gasoline from crude oil. This was followed by work in hydrofluoric alkylation, polymerization and isomerization. These developments led to the development of high-octane fuels that could be produced on a large scale, as well as for the production of synthetic rubber.
This became critically important in the years that followed, as the world became engulfed in World War II. While Axis forces struggled for sources of oil to fuel their war effort, Allied forces were comparatively awash in high-octane aviation gasoline. This afforded the Allies a critical advantage in air superiority, allowing tactical advances that likely shortened the war.
While UOP benefited greatly from a pooling of industrial patents during the war, by 1944 the legal basis for the company’s core refining patents was called into question over an unproven accusation of judicial partiality. Customers not only withheld royalty payments, but prepared to sue UOP to recover past payments. In addition, UOP’s longtime president Hiram Halle, architect of the company’s business model, died only hours after learning of the loss of a key court battle.
To avoid becoming ensnared in UOP’s legal problems, the oil companies that owned UOP placed it into a trust to support the American Chemical Society.
In 1931, faced with an adverse judgment in favor of UOP, a consortium of defendants banded together to purchase UOP for $25 million. This consortium, the United Gasoline Corporation, was jointly controlled by the Shell Oil Company and Standard Oil Company of California (present-day Chevron), and later included the Standard Oil Company of Indiana (later Amoco, and now BP), Standard Oil Company of New Jersey (Esso, now ExxonMobil), The Texas Company (Texaco, now Chevron), the Atlantic Refining Company (ARCO, now part of Sunoco and BP) and Gulf Oil (also now part of Chevron).
To allay concerns over antitrust, UOP was obliged to continue its work with independent refiners, in effect, becoming the center of research for the entire industry. But for the major oil companies, the acquisition of UOP brought peace after 15 years of litigation.
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Also in 1931, Vladimir Ipatieff joined UOP as head of research. Recruited by UOP’s chief chemist Gustav Egloff, Ipatieff was one of the world’s foremost chemical scientists. A former czarist general, Ipatieff was head of the Soviet Union’s chemical industry, but had become concerned that he would be engulfed in Stalinist purges that had claimed the lives of several several associates. Ipatieff was so close to Czar Nicholas II that the Russian royal family had been held under protective custody in his home in Yekaterinburg, only to be killed in Ipatieff’s basement by Bolshevik soldiers on July 17, 1918.
At UOP’s Riverside laboratory, Ipatieff tested his theories by constructing miniature refineries that could be scaled up a million times into to full refineries. The world’s foremost chemical engineers flocked to UOP for a chance to work with Ipatieff, who — like Edison and Einstein — came to be known by only his last name.
Gasoline, which until then had been used as a solvent, had found favor as a fuel in internal combustion engines. With mass production of automobiles by Ford, General Motors and other car companies, these engines were being produced by the millions, generating strong demand for gasoline.
Jesse Dubbs retired in 1914 and died four years later. But Carbon Dubbs remained with the company to prove the efficacy of his father’s invention. While he did this, he spent most of his time on other projects, much to the displeasure of the company’s president Hiram J. Halle.
In 1919, the year the company changed its name to Universal Oil Products, Carbon Dubbs revealed his secret work – Clean Circulation, a refining method that improved on his father’s invention by circulating a quantity of refined gasoline back into the feedstock. For Halle, this meant a profound change in the company’s business.
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No longer just a paper company formed to enforce patent rights, UOP now had a new and improved method for refining oil. Because UOP lacked the capital to become a refining company itself, Halle decided UOP should license the Clean Circulation process to any refiner in exchange for a royalty fee, based on production. For its part, UOP would engineer its customers’ refineries and guarantee performance. This would remain UOP’s business model for the next century.
In 1921, UOP established its Riverside research and development laboratory in present-day McCook, Illinois, as a focal point where the best and brightest scientists could create new products and provide scientific support for the oil refining industry.
Beginning with Shell’s Roxana refinery in Wood River, Ill. in 1922, UOP signed dozens of customers – initially in the United States, followed by Japan, China, India, Romania, the United Kingdom and The Philippines. The steadily rising income from these licensees helped to fund UOP’s legal action.
UOP training programs are focused on building the knowledge and skills of your team. We utilize experience and expertise built up over a century in the oil and gas industry to teach and motivate your workforce; and help you achieve safe, efficient and stable operations.
View the 2015 schedule to register for available courses.
We’re excited to announce new offerings and locations in this year’s programs:
Several offerings are being held in a new location, Istanbul, Turkey, Miami, USA and Prague, Czech Republic. We hope these locations provide attractive destinations for your training needs.
UOP continues to offer a popular training class, the Engineering Design Seminar. This intensive nine week program gives participants the opportunity to learn the fundamentals of refining process design. Early registration is suggested as this course often sells out.
Please visit the UOP Training Website for registration and additional information on our single-company courses, and self-study options including web-based training, expert systems, and training simulators.
We look forward to supporting your training needs in 2015.
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UOP hosted the 2015 Unicracking Technology Conference in March in Singapore. The conference joined UOP experts, Unicracking licensees and catalyst users from around the world. Attendees discussed key industry challenges, shared best practices, and learned about new technologies that can help improve refinery operations and meet the growing global demand for high-quality distillates.
2015 Conference Calendar
Aromatics Technology Conference, China
CCR Platforming User’s Conference, China
Oleflex Technology Conference, China
Gas Processing and Hydrogen Road Show, China
Russia Refining, Petrochemicals & Gas Processing
Conference, Moscow
European Refining Seminar, Rome
H2 Plant Symposium, London and United States
Western States Refining Conference, United States
For more information about conferences planned for 2015 or to request and invitation, please contact Conferences@UOP.com.
Separex Flux+ and Select membrane elements have been operating successfully at a number of customer sites with more than 1.5 years of continuous operation for both products.
At an EOR plant in west Texas, replacement of existing flux elements with Separex Flux+ elements has helped the customer increase the throughput by about 15% while using only 71% of existing membrane skid capacity.
At a gas processing plant in South Asia, the customer replaced existing flux elements with Separex Select elements. The hydrocarbon recovery increased from an average of 89% to an average of 95% during the demonstration phase of two months operating with Select membranes. This plant is producing pipeline quality gas. For such plants, increased hydrocarbon recovery means savings in compression and/or increased production.
UOP has been an Industry leader for proven membrane technology, from membrane research to manufacturing, with more than 30 years of field operating experience. UOP has in-house membrane R&D capabilities which enables continuing development of advanced products that go through a rigorous new product development process before deployment.
To learn more about UOP’s membrane technology, visit uop.com.
Gas plant operators are always looking to increase operating efficiency. Revamps are an opportunity to achieve this, along with higher capacity and improved incremental revenue.
In 2013, UOP added two new products to the Separex membrane element product line. Ideal for revamps, the new products, Separex Flux+ and Separex Select elements, are a drop-in replacement for the membrane elements in existing Separex systems. These elements can also be used with any CO2 removal membrane system that utilizes 8-8.25” spirally wound membrane elements.
Separex Flux+ Element
By replacing the currently installed Separex Flux elements with Separex Flux+ elements in an existing Separex system, the customer may realize:
An increase in profit resulting from up to 25% higher production. The existing Separex system will be able to process up to a 25% higher gas throughput.
A capital cost saving from debottlenecking the existing system. The existing Separex system will be able to treat a higher CO2 level at the same feed gas throughput to meet the same product specification, with minimal-to-no change in existing hardware.
Operating cost savings from debottlenecking downstream processing units by achieving a lower CO2 specification at the outlet of the Separex system.
Example:
The below table shows a hypothetical scenario where a plant is designed for 50 MMscfd capacity but the customer has more feed gas available to process. If the membrane system is fully loaded with existing elements, the only way to increase capacity would be to add more membrane housings.
This would require several weeks of delivery time in addition to longer plant down time for modifications/additions. Using Separex Flux+ elements as drop in replacement, the capacity increase can be achieved such that up to 25% more flow can be processed via the same membrane system with the identical amount of new membrane elements. This will take no additional tube or plant down time other than replacing older elements with Separex Flux+ elements.
Note: Two stage membrane system will also require enough additional compression power to process more feed. Calculations above does take that into account. The same example is applcable to single stage system with no requirement for permeate compression.
Separex Select Element
The Separex Select element is UOP’s new high-selectivity membrane element. It has up to 50% higher selectivity compared to Separex flux element and Separex Flux+. By replacing Separex flux membranes with Separex Select membranes in existing and/or new systems, the customer may realize:
An increase in profit from increased hydrocarbon recovery and reduced hydrocarbon emissions.
An increase in profit from extending the life of the well by reducing the feed gas flow rate to meet the same product gas nomination.
Reduced compressor operating costs for a multi-stage Separex system.
An increase in profit from higher gas throughput that can now be processed by the existing compressor in a multi-stage Separex system to achieve the same hydrocarbon recovery.
Example:
The below table shows a hypothetical scenario where the customer would like to improve they efficiency of an existing single stage membrane system to gain incremental revenue. There is no additional feed gas available to process since field may be declining in the capacity. By using Separex Select elements in the existing 1-stage system, profits can increase from higher hydrocarbon recovery (i.e. more product gas at the same feed gas flow rate and product CO2 specification).
Note: The Select membrane requires a larger amount of membrane area to perform the similar CO2 removal as Flux elements. The graph above takes the additional membrane area price in the account.
The need for high-purity olefin process streams has become even more critical to help protect the new generation, high-yield polyolefin plant polymerization catalysts. UOP provides the technical and application knowledge as well as adsorbent solutions to remove many contaminants and meet the high-purity requirements needed in these processes.
The performance of newer generation Ziegler-Natta type and especially metallocene polymerization catalysts in the production of polyolefins (polyethylene, polypropylene, etc.) can be adversely impacted by the presence of a wide range of contaminants in the feed monomer, comonomer, reaction controlling gas, solvent and recycle streams. Trace levels of these impurities impair polymerization catalyst efficiency (through deactivation of the catalyst) resulting in decreased polymer quality and yield with a resultant economic penalty. Through an understanding of all the relevant adsorption application technology, contaminants of concern in polyolefin production, and optimum adsorption system operating conditions, adsorbent units can be designed to assure ultimate protection of the polymerization catalyst while providing enhanced effective life for the adsorbents installed. Contaminants of concern in the production of polyolefins include H2O, CO2, CO, O2, oxygenated hydrocarbons (alcohols, ketones, aldehydes, ethers, peroxide, etc.), nitrogen based compounds (NH3, nitriles, amines), sulfur based compounds (H2S, COS, CS2, mercaptans, sulfides and disulfides), AsH3, PH3, SbH3, Hg and others.
Adsorption Application Technology Principles
Adsorption involves trapping of the contaminant (via condensation or electrostatic attraction) on the surface area of a solid; whereas, absorption involves removal of contaminants (via chemical or molecular action). Adsorbents typically have a porous structure with a high surface for removal of trace levels of polar or polarizable molecules from vapor or liquid streams. Adsorption can occur via a number of different mechanisms including physisorption, chemisorption, a combination of physisorption and chemisorption, ion exchange, and chemical reaction. Zeolite molecular sieves (metal aluminosilicates) have metal cations contained in the crystalline structure to balance the negative charge of the framework. The cation and crystalline structure of a molecular sieve determine the size of the pore opening; thereby, selectively adsorbing or excluding a molecule based on its diameter (i.e., concept of “molecular sieving”). On the other hand, activated alumina based and silica gel type adsorbents are amorphous in nature with a wide range of pore openings. (Figure1).
Therefore, unlike molecular sieves’ size exclusion phenomenon, activated aluminas utilize complex surface chemistry for removal of contaminants. The modification of the activated aluminas surface functionality by inorganic “promoters” enhances its adsorbent performance particularly via chemisorption of specific contaminants. A hybrid adsorbent that is a composite of molecular sieve (zeolite) and promoted alumina can take advantage of the complementary performance characteristics of both materials. Metal oxide based adsorbents with optimized pore structure irreversibly binds hydride contaminants via an oxidation-reduction mechanism. UOP manufactures molecular sieve, activated alumina, composite and metal oxide/sulfide on alumina type adsorbents.
One concept relevant to our discussion is selectivity (i.e., preferential adsorption) involving the physisorption of contaminants on molecular sieves and composite adsorbents. Figure 2 details the predicted order of selectivity on a large pore molecular sieve with H2O preferentially adsorbed over all other polar contaminants. Due to selectivity, a more strongly adsorbed polar molecular can displace or “roll off” a less strongly adsorbed molecule.
As noted in Figure 2, adsorption of contaminants involves generation of heat of adsorption, which typically results in minimal heat release to the carrier stream since the level of contaminant to be adsorbed is quite low. Adsorbents have the ability to remove contaminants to ultra-low effluent specifications (ppb) to assure protection of downstream catalysts, processes, and equipment. The final attainable effluent specification for each contaminant depends on the adsorption mechanism and properties of the product utilized in a specific application.
Adsorbents and catalysts share key attributes: porosity, surface area, and surface functionality. The reactivity of an adsorbent (leading to undesirable side reactions) is of utmost importance when treating reactive streams such as olefins. Figure 3 compares the reactivity (to convert vapor phase isobutylene to higher molecular weight oligomers/polymers) of various adsorbents.
As the gas reacts over the adsorbents, the pressure drops indicating the initiation temperature at which the isobutylene is catalyzed. More reactive adsorbents catalyze isobutylene at lower temperatures. In addition to this catalytic oligomerization of olefins, another reaction of concern in the polyolefins industry is the double bond shift (Figure 4) of an alpha olefin (butene-1, hexene-1, octene-1) used as a comonomer in polyethylene production processes.
This double bond shift (examples: butene-1 to butene-2 or hexene-1 to hexene-2) is an unwanted reaction (resulting in a negative impact on product quality and process economics) that can potentially occur when adsorbents remove oxygenates from the fresh and recycled comonomer streams.
Another issue when adsorbing contaminants from olefinic streams is coadsorption of the carrier stream by large pore molecular sieves such as 13X where a large amount of heat can be released triggering possible exothermic reactions that endanger equipment and personnel. To prevent this situation, either: 1) a preload step can be used before the initial exposure of a fresh or regenerated adsorbent to the olefin containing stream; or 2) a low reactivity, low olefin coadsorption composite adsorbent, such as UOP’s AZ-300 or AZ-400 can be substituted for 13X type molecular sieve in this application. The preload procedure involves using a low (<5 Wt%) concentration of the olefin in a non-adsorbed carrier stream (example: N2) to slowly saturate the adsorbent with the carrier stream olefin and safely remove the heat of adsorption. (Figure 5)
In process facilities, the solid adsorbent is loaded into a pressure vessel and the contaminated process stream passes through the packed bed. Dynamic adsorption takes place across a mass transfer zone that progresses through the adsorbent bed as a stable wave or “front” (Figure 6) until contaminant breakthrough occurs.
Adsorbent requirements must be sufficient to accommodate the equilibrium section as well as the mass transfer zone’s length. An adsorbent’s equilibrium capacity for a contaminant is dependent on the concentration of the contaminant in the feed stream as well as its temperature. Adsorbent regeneration is accomplished via a thermal and/or pressure swing driving force. Thermal regeneration of molecular sieves, activated aluminas and composite adsorbents are typically conducted by passing a hot (150-290°C) gas such as N2 or contaminant free light hydrocarbon through the packed bed to desorb the contaminants. The heating step is followed by a cooling step (utilizing a contaminant free gas or liquid stream). Adsorbents such as metal oxides/ sulfides, where chemical reaction is the mechanism for contaminant removal, are operated in a non-regenerative mode. The contaminants are tightly bound to the adsorbent and remain on the material through the useful life of the product and proper disposal following recharge of the vessel.
Adsorbent Applications in Polyolefin Production Processes
A technical service available from UOP at no charge is our adsorption unit design service; whereby, after completion of a design worksheet (Figure 7), an adsorption system (for removal of contaminants from any stream within a polyolefin plant) can be specified including vessel geometry, adsorbent(s), regeneration gas requirements and other parameters. This service is available to engineering construction firms, process licensors and end users.
The operating conditions, contaminants removed, adsorbents installed, regeneration gas requirements and relevant adsorption application technology will be reviewed for selected adsorption systems in polyethylene and polypropylene plants designed by various polyolefin process licensors.
Figure 8 is a simplified process flow diagram for the catalytic removal of O2 and CO (utilizing UOP GB-620 CuO on alumina material in a lead – lag bed configuration) from the feed ethylene stream to a swing LLDPE (linear low density polyethylene)/ HDPE (high density polyethylene) plant. This same general process scheme would apply if O2 and/or CO removal is required from the propylene monomer feed stream in a PP (polypropylene) plant or from the nitrogen reaction controlling gas stream or the nitrogen regeneration gas stream in a LLDPE plant. If H2S and/or COS is present in the ethylene or propylene monomer stream, it is necessary to install a non-regenerative sulfur guard bed (utilizing UOP GB-217, GB-220, GB-417, or GB-420 adsorbent) or a regenerative adsorption system (utilizing UOP’s AZ-300 composite, AZ-400 composite or SG-731 promoted alumina adsorbent) upstream of the GB-620/622 material for O2 removal since the H2S or COS will deactivate its catalytic ability.
Figure 9 details the reactions involved in the removal of O2 and CO over CuO based products. As noted, to effectively remove O2 in the lead bed, the GB-620 must be in a reduced copper form, CuO. The CO + ½ O2 reaction occurs over CuO. CO reacts with CuO in the lag bed. Whereas O2 removal from ethylene, propylene or nitrogen can be accomplished at either an ambient or elevated (90 to 110 OC) temperature, CO removal is only effective in the elevated temperature range. Prior to bringing the lead bed on-line, an initial reduction step is required to reduce the GB-620 to the CuO state. This initial and subsequent reduction steps (to “regenerate” the GB-620) involves the step wise ramping of the H2 content in the N2 “regeneration” gas stream. Likewise a periodic “regeneration” of the GB-620 in the lag bed is required to reconvert the CuO back to CuO with an oxidation step (with a similar ramping of the O2 content in the N2 “regeneration” gas stream).
Figure 10 details the feed ethylene treating system for a HDPE plant in Western Europe. Note that H2O, NH3 and oxygenates are removed via physisorption (with H2O preferentially adsorbed) on UOP’s AZ-300 composite adsorbent; whereas, CO2 is removed using UOP’s CG-731 promoted alumina adsorbent via a combination of physisorption and chemisorption with H2S removed via chemisorption. A compound bed of two adsorbents is used in one process vessel. No preload step is required with use of these specified adsorbents.
Figure 12 details the butene-1 comonomer treating system for that same Chinese LLDPE/HDPE plant where UOP’s 3A-EPG molecular sieve is at the bed inlet (due to contaminant selectivity concept) to physisorb the H2O with the remainder of the adsorbent bed being AZ-300 for removal of oxygenates (CH3OH, MTBE, peroxides). Alpha olefin isomerization, if it occurs at all, is minimized through use of these low reactivity adsorbents.
Figure 13 details the hexene-1 comonomer treating system for a HDPE plant in Korea utilizing a different licensed process than the previous polyethylene plants discussed.
Figure 14 details the regenerative adsorption system to treat the feed propylene stream (sourced from the on-site ethylene plant) to a polypropylene plant in China. Whereas H2O and oxygenates are respectively physisorbed on UOP 3A-EPG 1/16 molecular sieve and AZ-300 7×14 composite adsorbent, COS removal with UOP’s SG-731 7×12 promoted alumina based adsorbent is completely via chemisorption, requiring a higher regeneration gas (N2) temperature than is required to desorb the physisorbed contaminants from AZ-300.
For all the above detailed applications for AZ-300 composite adsorbent, UOP’s recently developed, high capacity, composite adsorbent, AZ-400 can also be utilized to assure optimum contaminant capacity particularly for the less polar compounds that can deactivate polymerization catalysts.
Figure 15 details the non-regenerative adsorption system to treat the feed propylene stream (sourced from a petroleum refinery fluid catalytic cracking unit) to a polypropylene plant in Eastern Europe. The two UOP GB metal oxide on alumina adsorbents specified remove the various sulfur contaminant species via chemical reaction.
In addition to these applications just discussed, other contaminants including aldehydes, carbonyls, nitriles, amines, CS2, DMS (dimethyl sulfide), PH3, SbH3, and Hg can be removed by UOP adsorbents (AZ-300, AZ-400, SG-731, GB-346S, GB-347S, GB-238, and others) from polyolefin plants’ feed monomer, solvent, comonomer, reaction controlling gas, and recycle streams.
Conclusion
A wide variety of contaminants must be removed from various vapor and liquid phase streams within the process to assure adequate protection of new generation, high yield polyolefin plant polymerization catalysts. UOP has the product application technology expertise, technical services and broad adsorbent product line to provide polyolefin plant polymerization catalyst protection.
Refinery produced LPG streams are often upgraded to high quality gasoline blendstocks or high-purity petrochemical products. These LPG streams are ultimately impacted by stringent finished-fuel and product specifications.
For example, as part of a comprehensive federally mandated plan to reduce atmospheric emissions, the United States Environmental Protection Agency is implementing its Tier 3 regulations in 2017. Among these regulations are standards that will require all finished motor fuel gasoline blends to contain no more than 10 wt-ppm sulfur. Merox technology can be implemented to meet this challenge by significantly reducing the total sulfur in alkylation unit feeds and light naphtha streams to facilitate compliance with the upcoming governmental regulations.
UOP has recently introduced two major technology improvements to the reliable Merox process, the Enhanced Prewash configuration and the MVP Regeneration design. UOP’s Extractor Plus with Enhanced Prewash design is the only technology commercially available that will remove all extractable sulfur (H2S, COS and mercaptan sulfur) within a single vessel, thus reducing plot space requirements by as much as 25%, and capital investment by more than 25%.
The MVP Regeneration design features a more robust and compact regeneration section that reduces re-entry sulfur by a factor of five (5x), so ultra-low sulfur specifications can be easily and efficiently achieved. The compact design and modular construction of the MVP Regeneration section reduces plot space requirements by more than 25% compared to the traditional regeneration section featured in previous Merox unit designs. A further benefit of the new design is that sulfur emissions in the spent air stream resulting from Merox regeneration are reduced by 99%. MVP Regeneration can be installed as retrofit of existing facilities or incorporated in new Merox unit designs. MVP Regeneration is supplied by UOP Modular Services and easily commissioned at site. Modular construction can shorten the overall project schedule by six months and ensure achieving obligatory 2017 fuel standards.
Since its introduction in 1958, UOP has continuously worked to improve the Merox process to reduce capital and operating costs, reduce plot space requirements, improve operability and help operating companies achieve ever-tightening product specification requirements. More than 1800 Merox units have been licensed making Merox technology the world’s preferred treating technology. Since its introduction last year, more than five new Merox units have incorporated the new Enhanced Prewash configuration. The first Merox unit with the MVP Regeneration design was licensed to a US Gulf Coast refiner and is scheduled to be commissioned in late 2015.
