Then it gets rather more high-tech. Capua's high-vacuum, low-temperature equipment removes bergaptene, an irritant, from the oil; and it is then stored under nitrogen gas to stop it oxidising.

Considering the high contents of olefins and nitrogen, the whole fraction of delayed coker distillates (including light and heavy naphtha, gas oil) must be hydrotreated.

Nitrogen gas - lift not only has become a major fluid flowing method, but also been successfully used in high pour - point oil well, thus opening a new way of special oil recovery.