Three projects expand product capacity of Memphis refinery

The top of the new east crude-unit tower, shown on the left, is being lifted to match its bottom portion. The completed tower and associated structure are shown in the right photo (Fig. 4).

• Cranes erected the new east crude-unit kerosine/diesel stripper in December 1998 (Fig. 5).

To continually meet local demand for gasoline and kerosine, Williams Energy Services has more than doubled its Memphis refining capacity since 1990.

In the past year, the Williams Memphis refinery, the only refinery in Tennessee, has undertaken three major projects to further this goal: installation of a new C3, C4 splitter, expansion of the east crude unit, and installation of a new catalytic reforming unit.

In 1990, the refinery's crude-distillation capacity was 60,000 b/d. Today, with most of the east crude-unit expansion complete, the refinery has a capacity of 140,000 b/d. With the completion of the new reforming unit in early 2000, the refinery will boast a 160,000 b/d capacity.

The refinery takes light, sweet crude via the Equilon-Capline pipeline system and converts it into gasoline, jet fuel, diesel fuel, fuel oil, propane, and propylene. The refinery-flow diagram in Fig. 1 [82,712 bytes] shows the feeds and products of the Memphis refinery.

History¹

This 140,000 b/d refinery had modest beginnings. In 1941, the refinery began operations under the stewardship of Delta Refining Co. Its capacity then was 3,000 b/d. It had only a crude unit and a Dubbs thermal cracker, and the crude feed came in by railcars.

Mapco Inc. purchased the refinery from Earth Resources in 1981. By that time, the refinery was capable of handling 40,000 b/d of crude feed. It had a hydrofluoric acid (HF) alkylation unit, a vacuum distillation unit, a catalytic reformer, and a 30,000 b/d fluid-catalytic cracking unit (FCCU).

In 1982-83, Mapco added 25,000 b/d of crude-distillation capacity to the refinery, making it a 65,000 b/d refinery.

Further major improvements were completed in the 1980s:

• In-line gasoline blender (1980)
• 46 megawatt totally redundant electrical substation (1980)
• Sulfur recovery unit (SRU; 1983)
• Isomerization unit (1987)
• Cryogenic recovery unit (1989).

In the past decade, Mapco completed several more major expansions.

In 1991, it expanded the FCCU to 40,000 b/d and installed a wet gas scrubber. At this time, Mapco also installed a new distillate hydrotreater, a reformer, a marine-vapor recovery system, a closed and vented API separator, and low-NOx burners in the existing crude furnaces.

The FCCU was further expanded to 45,000 b/d in 1995. This expansion simultaneously increased the crude-distillation capacity to 100,000 b/d.

In 1996, the refinery undertook several debottlenecking projects, collectively called Operations Enhancement Projects. These projects consisted of a new saturated-gas recovery unit (1996), a new FCCU air blower (1997), and expansion of the HF alkylation unit (1997).

The saturated-gas recovery unit and the FCCU air blower increased FCCU capacity to 60,000 b/d and crude capacity to 120,000 b/d. The new saturated gas recovery unit boosted the liquid-volume recovery of the refinery by 2%. Fig. 2 [73,956 bytes] illustrates the refinery's growth in liquid-volume recovery.

Enhancements to the HF alkylation unit accomplished three items: It doubled the alkylate product from 4,000 b/d to 8,000 b/d, increased the product octane, and lowered the olefinicity of the gasoline pool.

At this time, several pieces of safety enhancements were added to the unit: a dump-drum system to evacuate HF, automatic shut-off valves, and tandem-pump seals.

On Mar. 28, 1998, Williams Cos. Inc. acquired Mapco Inc., which created the Williams Memphis refinery.

Market

The refinery supplies gasoline and distillate products to Memphis and its surrounding area. With its close proximity to the Mississippi River, including river and rail distribution, as well as its expanding interstate highways, Memphis has been dubbed, "America's Distribution Center."

There is a high demand for premium gasoline in Memphis. An analysis of data from the Energy Information Administration² reveals that Tennessee ranks third in the nation in terms of amount of premium gasoline sold per capita. Only New Jersey and Maryland supply more premium gasoline per state resident.

The Memphis refinery also supplies 100% of the jet fuel used by the Memphis airport. Federal Express Corp., headquartered in Memphis, heavily uses this airport to run its business. According to an annual survey by Airports Council International, the Memphis airport handled more cargo than any other airport in the world in 1997.³

All of the refinery's crude supply is fed from the Equilon-Capline pipeline, to which Mapco was connected in 1984. This pipeline was originally constructed by Shell Oil Co. and its partners to transport oil from St. James, La., to the upper Midwest.

The pipeline can currently transport 140,000 b/d of crude to the refinery and is being upgraded to 165,000 b/d. A 6-in. products pipeline from the refinery to the Memphis airport has a capacity of 31,000 b/d.¹

Internal culture

Unique about the Williams Memphis refinery is the way in which many of its projects are launched. In 1994, the refinery implemented a cultural revolution so that a "bottoms-up" approach was encouraged.

Every 3-4 weeks, eight to ten refinery employees from several departments meet to talk about business improvements. Persons in the meeting come from a range of jobs, from operators to laboratory technicians to accountants.

In this atmosphere, every employee is given the chance to take and to receive: the employee can provide input to refinery operations while better understanding the business plans of the company. Emmett Reagan, Williams' director of support services, admits the culture didn't change overnight. It was, however, a cultural experiment that he feels has been well worth the effort. "Projects

developed from the ground up in organizations maximize the effect of a project when they're implemented. Our projects have been successful, and I credit our culture to this success."

The projects heretofore described were all discussed at these monthly business-planning meetings. Reagan added, "We have empowered our people in a way that allows them to contribute directly to the refinery's bottom line. In an era when some refineries are closing, we've been able to grow because our people are involved in the strategy process and continually bring new ideas to the table."

New splitters

In 1997, the refinery entered the petrochemical business when it modified the depropanizer section of the polymerization unit to produce about 2,000 b/d of a 75% propylene/propane mixture.

In January 1998, the completion of a new C3, C4 splitter increased propylene/propane production to 6,000 b/d. Most of the product is exported to the Gulf Coast.

The project consisted of a new fractionation tower, two new spherical storage tanks (25,000 bbl each), and a new north LPG rail loading facility. The new rail facility doubled the number of rail car spots from 12 to 24.¹

The splitter takes olefin feed from the FCCU and separates propane/ propylene from butane/butylene. The butane/butylene mixture is processed in the refinery alkylation or polymerization units, while the propane/ propylene stream is exported for further processing as a chemical feedstock.

With propylene being diverted from the polymerization and alkylation units, the new splitter allows higher-octane product to be produced from the alkylation plant and reduces the load to the polymerization unit.

East crude-unit project

Before November 1998, the east crude unit had a capacity of 40,000 b/d. The project increased the unit capacity to 80,000 b/d, which, combined with the west crude unit's 80,000 b/d capacity, gives the refinery 160,000 b/d.

Without the new reforming unit, however, the refinery does not yet have the infrastructure to run 160,000 b/d. Fig. 3 [108,933 bytes] tracks the quantity of refinery crude-unit and FCCU feeds since 1980. The east crude unit was originally planned with two phases, but currently has three. The first two phases were completed in November 1998. The third phase is in the mechanical design stag

e and is expected to be complete at the end of 1999. The scope of the three phases are as follows:

1. New tower (Fig. 4) and furnace for the east crude unit. The existing tower was converted to a preflash tower for the unit.
2. Debottlenecking of heat exchangers, pump upgrades, and a new kerosine/diesel stripper. The kerosine/ diesel stripper was completely fabricated offsite and erected in one stage at the refinery (Fig. 5).
3. Expansion of east crude-distillation unit to 100,000 b/d.

The new kerosine/diesel stripper increased the reliability of the supply of kerosine to the Memphis airport. Today, both the west and east crude units can make kerosine, whereas, previously, only the west crude unit could produce kerosine.

This project improved the refinery in three ways: increased crude-distillation capacity, increased reliability of kerosine and diesel supply, and better cuts and better yields from the new tower.

MPEC Inc., Houston, completed the process design for Phases 1 and 2. Mustang Engineering Inc., Houston, designed the plant, and Turner Industries Ltd., Baton Rouge, performed the construction.

During peak construction in the first week of November, there were 200 people involved in the construction of the project in the refinery. The safety team reported only one recordable injury in 100,000 project manhours.

Phases 1 and 2 cost $28 million. The cost of Phase 3 has not yet been completely estimated.

An almost unheard of feat in projects of this size, Phases 1 and 2 started up 2 months early and were under budget. Fred Collier, refinery engineering manager, credits the early start-up time to the cooperation of the refinery and contract employees, fast deliveries, and a well-planned project.

The start-up was uneventful. "It started up like it had been there for 10 years," said Collier.

New reformer

To meet the high demand for premium gasoline in the Memphis and surrounding areas, Williams is undertaking a $123 million project to build a new catalytic reforming unit and expand its naphtha hydrotreating unit.

The project will increase its premium gasoline production by 20,000 b/d.

The reforming unit was designed and licensed by UOP LLC. It will use UOP's CCR Platforming technology. Williams has chosen a 36,000 b/d continuous catalyst-regeneration unit to replace its existing 15,000 b/d semiregenerative one.

Howe-Baker Engineers Inc. will provide engineering, purchasing, and construction per a lump-sum contract. It began engineering in September 1998.

The project is currently in its first phase of construction and is not expected to be complete until the second quarter of the year 2000. Jeff Peterson, manager of the CCR project, expects peak of construction to occur in the fourth quarter of 1999, during which time 300 people will be on the project.

New control equipment associated with the CCR project will be part of a distributed control system.

Peterson states four reasons for the project:

1. To better supply the refinery's customers with gasoline.
2. To continually grow the refinery.
3. To improve processing capability. The reforming unit will allow lighter grades of crude to be run.
4. To give the refinery more flexibility in choosing crudes.

While the reforming unit is being replaced, another project to upgrade the capacity of the naphtha processing train will be ongoing. Equipment that will be idled as part of an alkylation-unit expansion will be used to make a second naphtha process train. In the end, Williams will have converted its one-train, naphtha-hydrotreating unit to a dual-train unit.

The process engineering for the dual-train naphtha processing project was contracted to MPEC Inc. Mustang Engineering will be doing the detailed design, and the contractor for construction has not yet been determined.

Permitting

The permitting process for expansion of the east crude unit, expansion of the FCCU, and construction of the new reformer lasted from October 1997 to July 1998, a relatively short period for permitting. The project essentially began in October 1997 when Mapco fast-tracked a prevention of significant deterioration (PSD) permit for county approval to expand the crude unit.

In March 1998, Williams submitted the PSD permit application to the Air Pollution Control Division of the Memphis Shelby County Health Department for review and approval. The permit for the projects was issued on July 10, 1998.

A few days later, Williams began construction of the east crude-unit project.

"Usually, the process takes 18-24 months," said Dale Morris, Williams' environmental manager, "but we worked so closely with the Shelby County Health Department that we basically got its approval before submitting the application."

Upfront, the company established a team to take charge of the permitting process for the projects. The team consisted of Trinity Consultants, Dallas, Williams' legal counsel, several engineers from the process engineering group, and a couple of representatives from the environmental group.

To comply with New Source Performance Standards (NSPS), Williams incorporated both ultra-low NOx burners and low NOx burners in its new crude-furnace design.

Today, in compliance with its state operating permit, Williams has submitted its proposal to demonstrate how to test the east crude units' emissions.

References

1. Collier, Fred L., "Williams Presents Refinery History," Apr. 28, 1998.
2. "Refiner Motor Gasoline Volumes by Grade, Sales Type, PAD District, and State," Petroleum Marketing Monthly, January 1999, Energy Information Administration.
3. Airports Council International bulletin, "Worldwide Passenger Traffic Up 5%, Cargo Up 8% in 1997," April 1998.

Copyright 1999 Oil & Gas Journal. All Rights Reserved.