What is Pyrolysis?
Pyrolysis of plastics thermally degrades the plastic, breaking the bonds of the polymer to produce lower molecular weight oligomers and monomers. The vapours resulting from the process are condensed to produce an oil/wax hydrocarbon product which has a high degree of purity and which are further refined in the process by selective fractionation to give predominantly diesel fuel. Pyrolysis typically takes place at relatively low temperatures in the range 350-450 deg.C. Pyrolysis transforms organic materials into carbonaceous char, oils and gases. During pyrolysis, the macromolecular structures of polymeric materials are broken down into smaller molecules, resulting in a wide range of hydrocarbons being formed. These pyrolytic products can be divided into a noncondensable gas fraction, a liquid fraction (consisting of paraffins, olefins, naphthenes and aromatics), and solid residues (i.e. char). Pyrolysis of waste plastics appears simple in concept.
