1861

Wamsutta Oil Refinery

When crude oil comes out of the ground, it is a fairly disgusting and useless fluid. But once chemical engineers get involved and run crude oil through a refinery, a wide range of useful products appear. One of the first refineries in the United States was the Wamsutta Oil Refinery in Pennsylvania in 1861.

Crude oil is called a hydrocarbon because it is made primarily of hydrogen and carbon atoms. The carbon atoms have a tendency to chain together, with hydrogen atoms bonded to the carbon chains. The basic idea behind refining is that hydrocarbons behave differently depending on the length of the carbon chain. The longer the chain, the thicker the refined product. Butane (a gas at room temperature and pressure) has four carbons in its chain. Gasoline has eight. Kerosene has twelve. Paraffin wax has twenty.

To refine crude oil, start by heating it. The different chain lengths boil off at different temperatures. The vapor goes into a fractional distillation column to separate out all of the different products based on these temperatures.

If the primary goal of the refinery is to produce gasoline, then there are processes designed to produce gasoline-length chains. For example, a catalytic reformer can combine shorter carbon chains into gasoline-length chains. Catalytic cracking can take longer chains and break them down into gasoline-length chains. Different products from these different processes blend together to form gasoline at specific octane levels.

Another important part of the refinery process is the removal of contaminants. Sulfur is one of the more common. Sulfur in gasoline creates two problems. First, it forms sulfur dioxide in the combustion chamber. The sulfur dioxide mixes with rain to form sulfuric acid, also known as acid rain, a major ecological issue that lead to automotive emissions controls in the twentieth century. Second, sulfur destroys catalytic converters that clear up exhaust gases. A hydrotreater turns sulfur into hydrogen sulfide gas for easy removal.

The largest refineries can process nearly a million barrels of oil per day, making them gigantic collections of towers, pipelines, valves, and storage tanks covering many acres. Every part of the process involves engineering.

SEE ALSO Oil Well (1859), Automotive Emission Controls (1967), Trans-Alaska Pipeline (1977), Seawise Giant Supertanker (1979).

This is a modern oil, gas, and fuel refinery.