The Heart of the Verbund
Both steamcrackers are among the largest of BASF’s production facilities in Ludwigshafen and form the heart of the facility. A whole range of important basic chemical components for production are generated here on site.
Numerous value chains are started in the crackers, where straight run gasoline (naphtha) – consisting of long hydrocarbon chains – is ‘cracked’ using steam. The process results in shorter molecules; the basic components for subsequent production. The process consists of several steps: The naphtha is first mixed and evaporated with water vapour. It is then heated in giant ovens for a fraction of a second to around 840°C, which causes the naphtha to break down into smaller components. The hot gas is very rapidly cooled immediately afterwards. This prevents the cleavage products from breaking down further. The crude gas is then compressed. The first products form as a result of these process steps, for example pyrolysis oil and pyrolysis gasoline. Finally, the products contained in the mixture formed are further separated from each other by distillation, the products of which include primarily ethylene, propylene, butadiene, pyrolysis gasoline and hydrogen.
Ethylene and propylene are among the most important molecules in the chemical industry and they are preliminary products for plastics, paints, solvents, pesticides, vitamins and many more. Numerous companies on site rely on a constant supply from the crackers. The facilities are therefore in operation twenty-four hours a day. They process approximately two million tonnes of naphtha annually, which is transported to Ludwigshafen by ship and pipeline. Each year around 620,000 tonnes of ethylene and 350,000 tonnes of propylene are produced in both facilities.
Cracker I was completed in 1965; cracker II followed in 1980 with about double the capacity. It has an area of around 64,000 m² making it the size of thirteen football pitches. Steamcrackers I and II mostly operate independently of each other, which means that when repair work is being carried out in one facility the other can continue operating as normal. The steamcrackers’ flare-stacks, which can be seen from very far away, are not normally in use. Only in the case that gases are produced that cannot be used for production i.e. in the case of a TÜV inspection, are these gases burned via the flare-stacks.