This heading covers crude petroleum oils and crude oils obtained from bituminous minerals (e.g., from shale, calcareous rock, sand), i.e., natural products, whatever their composition, whether obtained from normal or condensation oil‑deposits or by the destructive distillation of bituminous minerals. The crude oils thus obtained remain classified in this heading even when they have been subjected to the following processes :
(1) Decantation. (2) De‑salting. (3) Dehydration. (4) Stabilisation in order to normalise the vapour pressure. (5) Elimination of very light fractions with a view to returning them to the oil‑deposits in order to improve the drainage and maintain the pressure. (6) The addition of only those hydrocarbons previously recovered by physical methods during the course of the above‑mentioned processes. (7) Any other minor process, provided it does not change the essential character of the product. The heading also covers gas condensates, i.e., crude oils obtained during the stabilisation of natural gas immediately upon its extraction. This operation consists of obtaining, mainly by cooling and depressurisation, the condensable hydrocarbons (C4 to approximately C20) from the wet natural gas.
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