At Stanlow, 20,000 litres of crude pass through the crude oil distillation unit every minute in the first step of the production chain. The crude oil is heated and distilled in the tall columns of the crude distiller to break it into different constituents known as ‘fractions’.
The heaviest fractions, condensing at the hottest temperatures near the bottom of the columns, are upgraded in the catalytic cracker to produce petrol and diesel components, or used as fuel in the refinery furnaces.
Fractions condensing around the middle of the columns include kerosene for jet fuel and gas oil for heating and diesel engines.
The lightest fractions, condensing at the coolest temperatures near the top, include gases such as propane, butane and naphtha, some of which are upgraded further in Stanlow’s catalytic reformer, converting them to petrol components and solvents.
The £200 million catalytic cracker complex uses advanced process technology to bring heavy fraction molecules into contact with a hot catalyst in a process which breaks, or ‘cracks’, the molecules to produce new hydrocarbon combinations for petrol, diesel, and chemical unit feedstocks.
Energy from the cracker is harnessed by a power recovery train, the largest in Western Europe, capable of generating 21 megawatts of electricity. This is fed back to help power the refinery and, together with the eight turbo alternators at the boiler house, enables us to export to the National Grid.
Propylene produced on the cracker is fed to the polypropylene plant at Carrington, near Manchester.
The hydrodesulphuriser plant uses a high temperature and high pressure catalytic process to remove sulphur from gas oil, which is in turn blended to make diesel. The hydrodesulphuriser was extensively refurbished in the late 1990s to help launch the UK’s first British-manufactured low sulphur diesel a year ahead of EU requirements.
The catalytic reformer (platformer) uses a platinum catalyst to upgrade light fractions by reducing their hydrogen content. The upgraded stream is then used to make LPG, chemical grade Benzene and Toluene and high octane petrol components.
In 2000, the £30 million hydrotreater 2 and gasoline 3-cut splitter were built and brought on line to enable robust production of low-sulphur petrol.
The business development and specialities team helps to maximise refinery income through the sale of blend components and niche products.
They supply UK customers with both white and black oil components, sulphur, toluene, marine grades, and some of Stanlow’s chemical streams. These products are sold via the jetty and gantry, or delivered direct via ship, pipe, or road car.
Constantly involved in the identification and analysis of opportunities to drive new market entries, they work with teams right across the refinery to understand product quality and supply chain capabilities.
Their expertise lies in understanding what the refinery is capable of delivering in order to respond quickly to changes in market demand.