Refining is a complex operation that relies upon upon the abilities of operators, engineers and planners together with innovative technology to produce merchandise that meet the demands of an intensely aggressive market.

A few of the best challenges for the refinery lately have been modifications to the specification of transportation fuels. The swap from leaded to unleaded petrol, the reduction of sulphur ranges in diesel and petrol, and, extra recently, the elevated use of biofuels in diesel and petrol, needed below European legislation, have all required main funding in new items and upgrades to existing refinery units.

At its easiest, oil refining is the separation of crude oil by distillation into totally different fractions. But many different complex processes are crucial to provide a full vary of products, that includes propane and butane (LPG), petrol, jet gasoline, diesel, marine fuels, heating oil, lubricant basestocks and fuel oil.

The refinery at Fawley also supplies feedstock to the adjoining ExxonMobil Chemical plant.

The catalytic cracking unit, known because the cat cracker, is one in all an important plants on the refinery. The cat cracker takes the heavier, less useful molecules from the distillation course of and breaks them down into smaller ones. These smaller, more helpful and therefore extra valuable molecules are used for manufacturing petrol and supply feedstocks for the chemical plant.

Refining processes use substantial amounts of energy and there was appreciable funding lately to make the refinery extra vitality efficient. A 拢60 million combined heat and energy (CHP) producing plant was installed in 1999, reducing power costs by more than 拢2 million per yr. Utilizing much less energy brings the additional environmental advantage of reducing emissions of gases similar to sulphur dioxide, carbon dioxide and nitrogen oxides.