https://doi.org/10.1351/goldbook.D01578
A thermal process which increases the molecular aggregation or @A00472@ in petroleum-based residues or @C01121@ leading to extended @M03849@ domains. This is achieved by holding them at an elevated temperature (usually \(750{-}765\ \text{K}\)) over a period of time (\(12\ \text{to}\ 36\ \text{h}\)). It is performed in a @C01144@ drum and is designed to ultimately produce @D01577@. The feed is rapidly pre-heated in a tubular furnace to about \(760\ \text{K}\).
Note:
@N04095@ is the premium product of the delayed @C01144@ process. It is generally produced from highly aromatic residues from, for instance, the steam @C01387@ of gas oil. Its appearance and preferred orientation of the @G02683@ is a consequence of the evolved gaseous products percolating through the @M03849@ which must not have too high a @V06627@. A close control of temperature, time and feedstock is essential. Lower grades, for instance @I03353@ cokes, are used for @C00829@ applied, for example, in the production of aluminium.
@N04095@ is the premium product of the delayed @C01144@ process. It is generally produced from highly aromatic residues from, for instance, the steam @C01387@ of gas oil. Its appearance and preferred orientation of the @G02683@ is a consequence of the evolved gaseous products percolating through the @M03849@ which must not have too high a @V06627@. A close control of temperature, time and feedstock is essential. Lower grades, for instance @I03353@ cokes, are used for @C00829@ applied, for example, in the production of aluminium.