Fawley refinery

The Esso refinery at Fawley, near Southampton, is the largest in the UK and one of the most complex in Europe.


Fawley refinery

Situated on Southampton Water, it has a mile-long marine terminal that handles around 2,000 ship movements and 22 million tonnes of crude oil and other products every year. The refinery processes around 270,000 barrels of crude oil a day and provides 20 per cent of UK refinery capacity.

We are committed to the very highest safety, health and environmental standards. But we are never complacent and are always exploring ways of further improving the safety and integrity of our operations.

Safety is the first priority in all our activities and our safety performance across the Fawley site is excellent. Workers at Fawley are significantly safer than the average in the European oil and chemical industry.

Although our safety performance continues to earn us awards, we know we are not perfect. We are committed to learning from our mistakes and will not be satisfied until our operations are flawless.

We continue to improve our environmental performance. The site's emissions to atmosphere have been falling steadily. This reduction has been achieved in part by the installation of a £60 million cogeneration unit. This highly energy efficient combined heat and power (CHP) unit burns fuel at an efficiency of 75 per cent, twice the efficiency of a conventional power station. Energy efficiency improvements over recent years have led to significant reductions in emissions - equivalent to taking 250,000 cars off British roads every year.

Our record on releases of oil in water used by the refinery is also excellent. The site draws over 300,000 tonnes of sea water from Southampton Water every day, mostly for cooling purposes. When it is returned to the sea after purification it is often cleaner than when it was extracted.

The thriving saltmarsh on the seaward boundary of the site is a testament to our environmental performance. It forms a Site of Special Scientific Interest (SSSI) that is home to some 22 species of birds. The land boundary of the site is surrounded by a tree screen containing some 50,000 mature trees and shrubs, originally planted some 50 years ago.

The refinery and adjacent chemical manufacturing plant are committed to being responsible neighbours and have a well-established programme of community links in the area. A newsletter about the Fawley site, Community Matters, is distributed to local residents six times a year.

Crude oil supplies

Our refinery at Fawley processes around 270,000 barrels of crude oil every day. Crude oil is transported by sea to the refinery's modern marine terminal, which handles around 2,000 ship movements and 22 million tonnes of crude oil and other products every year. The crude oil is pumped into storage tanks before being processed.

Each crude oil type has a unique composition and is a complex mixture containing many thousands of hydrocarbon molecules of different shapes and sizes. Crude oil from the North Sea is 'sweet', which means it is low in sulphur, whilst Middle East crude is 'sour' with a high sulphur content.

Not all crude oils are suitable for the production of all petroleum products. Before deciding which crude oil to process, consideration is given to the current demand for particular products, market prices and the various costs of the different crude oils.

It is also vital that appropriate feedstocks are available for ExxonMobil's chemical manufacturing plant that is adjacent to and integrated with the refinery.

Typically, the refinery will process over 20 different crude oils in any one year. This requires extremely sophisticated planning and highly flexible refinery operations.

Refinery operations

Refining is a complex operation that depends upon the skills of operators, engineers and planners in combination with cutting edge technology to produce products that meet the demands of an intensely competitive market.

Some of the greatest challenges for the refinery in recent years have been changes to the specification of transportation fuels. The switch from leaded to unleaded petrol, the reduction of sulphur levels in diesel and petrol, and, more recently, the increased use of biofuels in diesel and petrol, necessary under European legislation, have all required major investment in new units and upgrades to existing refinery units.

At its simplest, oil refining is the separation of crude oil by distillation into different fractions. But many other complex processes are necessary to produce a full range of products, that includes propane and butane (LPG), petrol, jet fuel, diesel, marine fuels, heating oil, lubricant basestocks and fuel oil.

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

The catalytic cracking unit, known as the cat cracker, is one of the most important plants on the refinery. The cat cracker takes the heavier, less valuable molecules from the distillation process and breaks them down into smaller ones. These smaller, more useful and therefore more valuable molecules are used for manufacturing petrol and provide feedstocks for the chemical plant.

Refining processes use substantial amounts of energy and there has been considerable investment in recent years to make the refinery more energy efficient. A £60 million combined heat and power (CHP) generating plant was installed in 1999, reducing energy costs by more than £2 million per year. Using less energy brings the additional environmental benefit of reducing emissions of gases such as sulphur dioxide, carbon dioxide and nitrogen oxides.

Refinery to customer

Hundreds of thousands of people in the UK depend on our quality products - whether it's fuel at a service station, heating oil for a local school or 100,000 litres of jet fuel to speed flights across the Atlantic, we have to ensure that our fuels are available when and where our customers want them 365 days of the year

Every day, we transport over 30 million litres of clean products - petrol, diesel, jet fuel and gas oils - from our refinery in the most efficient, safe and environmentally friendly way: by underground pipeline.

We operate nearly 700 kilometres of pipeline in a network that connects to five of our distribution terminals at key locations around the country and to facilities at Heathrow, Gatwick and Birmingham airports.

Most of the pipelines carry a number of different products. They are fed into the pipeline one at a time in a predetermined sequence. Pipeline operations are controlled using a sophisticated computer and information collection system that keeps track of the interfaces between products so that they can be separated on arrival at the terminal.

Most orders for fuel are processed by our European Customer Service Centre. Experienced customer service staff, computer-aided route planning and other initiatives such as night-shift deliveries, all ensure high levels of efficiency and customer service.

The final link in the delivery system, by road from distribution terminal to customer, is carried out by a contractor company that has a fleet of around 90 Esso-branded trucks.

Around 95 per cent of our clean products are transported by underground pipeline. The remainder accounts for transport to coastal distribution terminals that are supplied by sea.

Other products - for example, marine fuels or lubricant basestocks - that leave the refinery to go directly to customers or to other ExxonMobil locations are also transported mainly by sea.

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