English: 360° view of the Enefit 280 shale oil plant. The retort can be compared to a large airtight container used to heat and decompose raw organic matter without access to oxygen. In chemistry, such a process is called pyrolysis. The pyrolysis lasts about fifteen minutes and results in a vapour-gas mixture consisting of vapours of liquid products, water vapour and semi-coke gas. The solid product of pyrolysis is semi-coke. The vapour-gas mixture leaving the reactor is separated from semi-coke in a dust chamber and then in a cyclone.