Since oil was discovered in Saudi Arabia in 1938, pipelines have played an increasingly important role in the kingdom's economy. Initially their role was small: to deliver crude oil from oilfields to coastal terminals for shipment overseas and to move petroleum from offshore wells to the tank farms and terminals. But two recently completed pipelines - one for crude oil, the other for ethane and natural gas liquids (NGL) - are no less than the underpinning of the kingdom's economic future.
Stretching side by side from Saudi Arabia's eastern oil fields along the Gulf, across the Arabian Peninsula to Yanbu' on its western Red Sea coast, the twin pipelines are key elements in the development and economic unification of the kingdom - parallel bands binding the nation together and bringing to the western edge of the country the full benefits of the east coast oil harvest.
Cutting across Saudi Arabia, through a sun-scorched and often desolate landscape, from the sand dunes of the Dahna and the cliffs of the Tuwaiq Escarpment to the lava fields south of Medina and the rugged mountains of the Hijaz, the two pipelines will provide fuel and raw materials for the giant industrial city of Yanbu' now taking shape on the Red Sea shore 300 kilometers north of Jiddah (186 miles), and other important west coast projects.
The benefits of the pipelines, however, will not be restricted to Saudi Arabia alone. They will also be shared by its oil and gas-consuming customers - by bringing Saudi energy exports closer to western markets and reducing the possibility of delivery bottlenecks in the Gulf.
In the past, the kingdom could move some oil through the Trans Arabian Pipeline ("Tapline"), the 1,720-kilometer crude oil pipeline system (1,069 miles), running across Jordan, Syria and Lebanon to the Mediterranean. Since the mid 1970s, however, this outlet has not been feasible. The kingdom, therefore, shipped virtually all of its export production - vital to the economies of Europe and the United States - through the Gulf. Now, however, Pet roline - a new 1,202-kilometer pipeline (747 miles) - can transport oil overland across the Arabian Peninsula - from the east coast Abqaiq and Ghawar oil fields - rather than around it by sea. A new outlet for Saudi oil exports, Petroline now offers a brand new route, via Suez, to Europe and beyond.
Similarly, the 1,170-kilometer NGL pipeline (727 miles), linking gas processing plants in the Eastern Province with NGL fractionation and export facilities at Yanbu' will provide a partial alternative to Saudi shipments of natural gas liquids from the Gulf.
Constructed for the Saudi government by Aramco, which is responsible for designing, building and operating the kingdom's massive Master Gas System, the NGL pipeline was laid by a contractor's work force of 1,500 men, plus 100 support personnel, in less than 20 months.
Work on the NGL line began in November, 1978, when bulldozers first blazed a trail for backhoes that dug a minimum 1.83 - meter deep (six feet) trench across the peninsula. About one-third of the trench - some 400 kilometers (248 miles) - had to be blasted through rock - a job requiring 2,000 tons of explosives.
Compared to the early days of pipeline construction - when pipelaying was done by hand — laying the NGL pipeline was a highly sophisticated operation. Double jointed sections of pipe - two 12-meter lengths (39 feet) previously welded together and bent, where necessary, to fit the terrain - were strung over the trench by mechanical sidebooms, and the suspended sections were joined together by automatic welders. One of the welders passed through the pipe and the other moved along it; altogether, it took 45,000 welds to seal the 295,000 tons of the 66-, 71-, and 76-centimeter steel pipe (26,28, and 30 inches) used in the project.
The NGL line was one of the first major pipelines ever to be built by totally automatic welding techniques. Welding operations began March 3, 1979, and were completed in 479 days. Finished welds were checked for defects by radiography, and the pipeline sections given a double plastic tape wrapping to guard against corrosion. Then they were lowered into the trench, mile after mile, until, on July 28, 1980, the final section was lowered into place at its highest point: "Gunsight Pass," 1,082 meters (3,550 feet) up in the Hijaz Mountains.
Operations, as well as construction, of the NGL line are highly sophisticated; indeed the high-pressure NGL pipeline, computer monitored and controlled, is not only the longest but also the most sophisticated pipeline ever built for transportation of natural gas liquids. Controlled from Aramco headquarters in Dhahran - which receives information by microwave from 40 locations along the pipeline - the NGL line receives instructions over the same microwave system. In Dhahran, the Central Dispatch Center can also open and close main line valves by remote control - to isolate a section of the pipeline in case of emergency. A computer-based pipeline operating model to help detect leaks is being installed.
Impressive though it is, the NGL pipeline still cannot eclipse the crude line - Petroline-beside it. Indeed, the crude line, in statistical as well as economic and strategic terms, is even more impressive. With a diameter of 122 centimeters (48 inches), the crude oil pipeline will have one of the largest capacities of any pipeline system in the world. The new pipeline is already capable of moving 1.85 million barrels of crude a day - about one fifth of Saudi Arabia's average production in 1981 - and could handle 3.7 million barrels a day if the Saudi government decided to expand output.
Construction of the $1.6 billion Petroline system for Petromin, Saudi Arabia's General Petroleum and Minerals Organization, was supervised by the Mobil Overseas Pipeline Company, Inc., (MORCI) a subsidiary of Mobil Oil Corporation. Some 7,000 men were involved in the four-year design and building of the pipeline and export terminal, which, like the NGL line, involved working in difficult conditions in some of Saudi Arabia's toughest terrain.
Finally, however, on July 1,1981, the first shipment, 1.3 million barrels of crude oil, pumped across Arabia through Petroline, was ceremonially loaded aboard the aptly-named Petromin tanker Yanbu' Pride at Yanbu'. "It's a great day for us," said Petromin's Governor Dr. Abdulhady Taher, as the first crude to leave a Saudi Red Sea terminal gushed aboard the Yanbu' Pride at the rate of 130,000 barrels an hour.
Like the NGL line, the crude pipeline will be operated by remote control, but from Yanbu' rather than Dhahran. The controls will extend to the 11 pumping stations - spaced at roughly equal distances along the line - and to the 11 storage tanks which dominate the new export terminal and which suggest the importance of Yanbu' in Saudi Arabia's restructured oil export pattern. Each is capable of holding one million barrels of crude.
From the tank farm the export crude moves in two 142-centimeter (56 inch) diameter pipes to tankers offshore along a jetty and trestle causeway - stretching a total of 3.35 kilometers (two miles) out over coral reefs to three deep water loading berths; one can accommodate large tankers up to 500,000 deadweight tons, and the other two up to 275,000 tons each. And from there it goes, most probably, to Europe via a route 3,600 kilometers shorter (1,460 miles) and three to four days faster than the sea route around the Arabian Peninsula from the Gulf.
Both pipelines play a key role in Saudi Arabia's plans to create a new West coast industrial center at Yanbu' - and reduce the kingdom's dependence on crude oil exports. The NGL line feeds a gas fractiona-tion plant built at Yanbu' by Aramco - to process up to 270,000 barrels of natural gas liquids daily for export - and provide ethane as feedstock for a petrochemical complex. In turn, the petrochemical complex will produce some 450,000 tons a year of polyethylene and ethylene, most of it for export.
The Yanbu' fractionation plant - one of the largest of its kind in the world - went into operation in August this year, and the first tanker was loaded at the NGL export terminal in October. Meanwhile, the NGL pipeline had been put into service to provide fuel for the crude oil pipeline pump stations and to industrial consumers in the Yanbu' area. It was switched to NGL when liquid feed was required at Yanbu'.
At the moment, virtually all of the crude moved to Yanbu' by Petroline will be exported, but later, upon completion of two new refineries, some will be processed. Initially, the refineries will have a combined capacity of 420,000 barrels a day, but will be expanded. The larger of the two refineries, a joint venture between Mobil and Petromin, will refine 250,000 barrels daily of crude into finished gasoline, naphtha, kerosene, diesel fuel and heating oil for North American and European markets. The other, owned by Petromin, will be able to process 170,000 barrels per day for domestic consumption. Eventually the crude oil pipeline will also supply petroleum via coastal tanker to other hydrocarbon-based industries planned for the smaller town of Rabigh, midway between Yanbu' and Jiddah, including a 335,000 barrel a day refinery.
All of these projects represent a major shift by Saudi Arabia - away from almost total economic dependence on export of crude oil towards processing and sale of finished petroleum products, and a diversified economy built on foundations bound together by the twin trans-peninsular pipelines.