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Rendall process outline

The Rendall process is totally different from both conventional and emerging oil shale retorting processes.   It presents a radical new approach to conversion of oil shale kerogen to refinery-ready synthetic crude oil product:

  • efficient
  • economical
  • environmentally-responsible
  • scalable to large stream capacities

There are three main steps in the Rendall process:

Kerogen conversion

  • Maximising oil production from oil shale kerogen in a single reactor, at about 450°C and 42 bar:
  • simultaneous pyrolysis of the kerogen, and
  • hydrogenation of its breakdown products by tetralin (a potent hydrogen-donor, generated by hydro-treating of naphthalene in a mid-distillate recycle from the distillation section).

Supercritical solvent extraction

Separation of the heavy product oil coating from the spent shale residue, using a toluene-rich light-distillate recycle from the distillation section, to ensure that:

  • oil production is maximised, and
  • the shale residue leaves the process as a dry, oil-free, water-insoluble solid material for disposal as a benign mine fill, or further processing for recovery of mineral by-products &/or manufacture of Portland cement.


Separation of the combined streams of mid-light hydrocarbons (ex-kerogen conversion) and toluene + heavy oils (ex-solvent extraction) into:

  • synthetic crude oil product for despatch to the market, plus
  • internal process feed and solvent recycles, and
  • methane gas (for power generation, process heat and hydrogen production).