In operation since 1915

Shell's Martinez Refinery, in operation since 1915, is both a pioneer and a pacesetter. Throughout its history, it has amassed a tradition of technical achievement, and is currently one of the most complex refineries in the world.

Located 30 miles northeast of San Francisco on about 1,000 acres of land, Shell's Martinez Refinery combines state-of-the-art facilities and equipment to convert up to 165,000 barrels of crude oil a day into many useful products.  These products include automotive gasoline, jet fuel, diesel, petroleum coke, industrial fuel oils, liquefied petroleum gas, asphalt, and sulfur.

While high technology and expensive equipment are important in the daily operation of the Refinery, nothing is more important than our people.  More than 700 men and women fill jobs encompassing a wide variety of activities.  Most are highly skilled craftspersons and experienced operating personnel who work to make sure the Refinery functions safely and efficiently day and night.

There's also a large technical staff who plan for maintenance of equipment and construction of new facilities with safety, health, and the environment as primary considerations.  Engineers and inspectors help fine tune operations for improved efficiency, while chemists and laboratory technicians assist the entire Refinery in assuring product quality.

Many other professionals play an important part at the Refinery, providing their expertise in purchasing, finance, environmental stewardship, health and safety, communications, human resources, training, and other functions.

These people, as well as the thousands before them, have helped Shell's Martinez Refinery become an integral and respected part of the community.  We at Shell, are proud of that relationship and pledge to preserve it by continuing to conduct our business safely, with integrity and efficiency, and with a watchful eye on the needs and concerns of our neighbors.

History of Achievement

With the rise of automobiles and airplanes, demand in the United States for gasoline and other refined petroleum products increased rapidly shortly after the turn of the twentieth century. In 1913, under the auspices of the American Gasoline Company, the Royal Dutch/Shell Group built a shipping terminal along the Carquinez Strait in Martinez to import and distribute gasoline along the Pacific Coast. This was the beginning of a long history of achievement for what would become the Martinez Refining Company.

In August 1913, the company purchased oilfields in California's Central Valley. By the following year, it began construction of the refinery in Martinez and on a 170-mile pipeline to transport oil to its new facility. Completed in 1915, the refinery was Shell's first in the United States.

Processing its first barrel of oil in January 1916, the Martinez refinery made production history by using innovative techniques to become the first modern, continuously running refinery in the United States.

The Martinez Refinery handled up to 20,000 barrels of crude oil a day - a sizable amount in those times. Most of its production was "heavy" products, making the Refinery a leading supplier of lubricants on the West Coast.

During the 1920s, Shell invested heavily in developing new product technology. The Company's first research laboratory was located at Martinez, as was its first chemical plant, built in 1931.

The Martinez Refinery continued to grow and improve over the years. A major expansion project was the Light Oil Processing facility, completed in 1966, which involved building an entire, integrated, modern refining facility, including a catalytic cracker, a hydrocracker and distillation units.

In 1983, Shell completed an $800 million modernization of its California refineries, much of which was spent at Martinez, making the Refinery among the safest, most environmentally sound and efficient in the world.

In 1994, the Martinez refinery began construction on the $1 billion Clean Fuels project. Completed in 1997, this project enabled the Refinery to comply with new state and federal regulations, requiring the production of cleaner-burning gasoline. Reformulated gasoline has had a significant impact on improving air quality in the Bay Area by reducing vehicle emissions.

A joint venture between Shell Oil Company and Texaco Inc. in January 1998 resulted in a new name for the Martinez refinery: the Martinez Refining Company.  In October 2001, Shell purchased Texaco's share of the joint venture and on March 1, 2002 the company became Shell Oil Products US and the Martinez refinery became Shell Martinez Refinery.  Yet with all these changes, the refinery personnel continue to focus on meeting energy needs in a safe, environmentally sound way remains the same.

The Fine Art of Refining

Petroleum refining is a complex business, involving chemistry, physics, mathematics and several engineering disciplines.

Crude oil is not a single substance, but a mixture of hundreds of compounds made up mostly of hydrogen and carbon, along with sulfur, nitrogen, and many other elements in very small quantities.  These "hydrocarbons" range in density from materials as light as natural gas to those as heavy as road asphalt.

In crude oil, these substances are thoroughly intermingled.  Each of these compounds, however, boils at a different temperature, and that is the secret to separating them.

Distillation -- boiling a liquid, condensing the vapors, and then collecting the resultant separate liquids -- is the first step in transforming crude oil into petroleum products. Distilling separates different parts of the crude oil that are sent into various portions of the refinery, which are then sent on for future processing.

The majority of the Crude barrel is used for making fuels (gasoline, jet fuel, and diesel). The remaining portion is processed to make asphalt and petroleum coke. There are several major units at the refinery that accomplish this process.  The refinery has two (cokers), a catalytic cracking unit, a hydrocracking unit, a crude unit, and an alkylation unit among others.  All play a major role in the refining process.  The cat cracker is a major gasoline producing unit, while the hydrocracker produces diesel.

In these processes, additional lighter products are created - large hydrocarbon molecules are broken into smaller ones - and the resulting liquids are sent on to further processing. What remains is virtually pure carbon, or "coke." The coke produced by the Delayed Coker is sold as a fuel for power generation and industrial uses, whereas the coke manufactured by the Flexicoker is converted to a gas and is used to meet much of the Refinery's internal fuel needs.

The petroleum fractions emerging from initial distillation processes and from the Flexicoker and Delayed Coker are, for the most part, still far too heavy (that is, they are composed of hydrocarbon molecules that are too large) for use in gasoline, jet fuel, and diesel. However, under a variety of special conditions, these large molecules can be "cracked" - literally broken into smaller, more usable, varieties.

One of the Shell Martinez Refinery's major plants is the Catalytic Cracking Unit, or "cat cracker," as it is called. Heavy oils are mixed with a flowing sand-like catalyst at high temperatures and in a few seconds, are cracked into gasoline components and lighter gases.

Another catalytic process is hydrocracking, which takes intermediate oils, mixes them with hydrogen and passes this mixture over a catalyst at high pressure and moderate temperature. This converts them to gasoline, jet fuel, and diesel components.

Catalytic reforming and isomerization are processes that change the molecular structure of certain gasoline boiling range fractions. With the aid of a catalyst, low-octane gasoline fractions are chemically changed into a high-octane gasoline component suitable for blending into finished gasoline.

While many of the Martinez Refinery's big processing plants change heavy hydrocarbon molecules into lighter ones, units such as the Alkylation Plant and the Dimerization Plant do just the opposite. These plants take the lightest parts of crude oil and combine them to form gasoline components.

A careful concern for the environment -- both at the Refinery and where the products are consumed -- is an important part of Shell's operation.  Several processes -- hydrotreating and sulfur recovery among them -- safely remove sulfur and other unwanted ingredients of the original crude oil, thus; these elements won't be released to the atmosphere.

In addition to all of this processing there is significant blending involved to make these products.  Automotive gasoline, for example, is a mixture of many components and additives that meet octane and other specifications.  This is aided by computer, with instruments in modern control rooms telling operators what's happening at all times.  Shell even has special engines on site to test gasolines for the proper octane specifications.

As you can see, there are many aspects to the refining process, all of which are administered with great care.

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