With the clock ticking on the U.S. Environmental Protection Agency’s mandated introduction of ultra low sulfur diesel fuel, ConocoPhillips has submitted permit applications for the construction of an ultra low sulfur diesel production facility in the Kuparuk River unit on Alaska’s North Slope. The new facility will produce diesel fuel for all of the industrial operations on the North Slope and may also produce fuel for North Slope communities.
EPA requires diesel powered vehicles operating on the U.S. road system to transition in 2007 to low sulfur fuel containing 500 parts per million of sulfur and then to fully convert to the use of 15 parts per million ultra low sulfur diesel by 2010.
But EPA, recognizing the unique issues situation in Alaska, granted rural Alaska (those areas off the road and ferry system) an exemption from the requirement to switch to low sulfur diesel in 2007. One key issue in Alaska is, for example, the need for Arctic grade diesel fuel that will not gel in frigid winter temperatures.
This need for ultra low sulfur Arctic grade diesel poses issues for the North Slope oil industry — currently the industry uses Arctic grade diesel refined in two small-scale refineries known as topping plants in the Prudhoe Bay and Kuparuk oil fields.
Special North Slope deal
In June 2005 BP Exploration and ConocoPhillips signed an agreement with the State of Alaska for the transition to ultra low sulfur diesel on the North Slope.
Under that agreement, the whole of the North Slope, north of Atigun Pass in the Brooks Range, is classified as rural, under the terms of the EPA Alaska exemption. In return for this flexibility in interpreting the federal rules, the oil companies agreed to transition to the on-site manufacture of ultra low sulfur diesel by 2008, two years ahead of the EPA mandated timeframe. Additionally, the companies agreed that after the transition all North Slope diesel equipment would use the new fuel, regardless of whether that equipment was subject to EPA ultra low sulfur diesel rules. And the producers agreed to also require contractors to use ultra low diesel and would sell excess ultra low sulfur fuel to the North Slope communities.
Construction plans
The oil companies plan to meet their commitments by using the ultra low sulfur diesel facility that ConocoPhillips proposes to build.
“ConocoPhillips has determined the most economical and environmentally safe method to comply with the regulation is to produce ULSD on the North Slope,” the company said in its plan of operation for a proposed ultra low diesel facility. “Other alternatives investigated were: importing from Alaska or Canada; using gas-to-liquids fuel; and using compressed natural gas.”
ConocoPhillips is locating its new ultra low sulfur diesel facility at the Kuparuk field Central Processing Facility 3; the facility will strip sulfur from diesel fuel produced by the existing North Slope topping plants. The topping plan at Kuparuk’s CPF 1 will form the main diesel fuel source, with the untreated fuel passing through a new pipeline between the two central processing facility locations. The Prudhoe Bay topping plant will produce additional diesel fuel for delivery by truck for the new facility when fuel demand is high.
Ultra low diesel fuel from the new facility will pass through another new pipeline to new diesel storage and distribution facilities at CPF 1.
The new sulfur-removal facility will use hydrogen in a catalytic reaction that will convert sulfur in the fuel to hydrogen sulfide. A catalytic oxygenation process will then convert the hydrogen sulfide to solid sulfur. The sulfur will be formed into cakes that can be ground and injected into an appropriate disposal well in the Prudhoe Bay field.
Electrolysis of seawater
Hydrogen for the facility will come from the electrolysis of seawater diverted from CPF 1’s waterflood system, powered by two 3-kilovolt transformers connected to CPF 3’s electrical power system. Because the process requires pure water, a reverse osmosis plant will filter the salts from the seawater. The new diesel storage and distribution facilities at CPF 1 will require the addition of new pumps, a 5,000-barrel surge tank and a new truck loading rack to an existing diesel distribution facility.
The two pipelines that transfer untreated fuel to the sulfur-removal facility and back from that facility to the storage and distribution facility will be 3 inches in diameter and run parallel to each other alongside the seawater pipeline that passes between CPF 3 and CPF 1.
Pipeline construction will occur in the winter of the first half of 2008 and will require an ice road.
ConocoPhillips expects to start off-site module construction and some on-site facility work in 2007. The sulfur-removal plant modules, electrical transformers and new surge tank will arrive by sealift in August 2008. Other equipment will be trucked to the North Slope in March 2008, and the new facility should go into operation in December 2008.
