HEAVY OIL PRODUCTS IN THE META-STABLE CONDITION THERMAL CRACKING METHOD AND INSTALLATION

摘要

FIELD: oil and gas industry.;SUBSTANCE: invention relates to the oil refining and petrochemical industry and can be used, in particular, to increase the heavy oil feedstock processing depth. Heavy petroleum products thermal cracking method comprises the high molecular weight feedstock feeding to the heating zone, the feedstock heating to subcritical temperature, conducting the controlled intensive thermal cracking process, formed light fractions separation, feeding the remainder to mixing with the feedstock stream directed to the heating zone, wherein the cracking is performed in the feedstock metastable state, at that, the feedstock is transferred by heating under low pressure into the metastable state with enabling high cracking rate temperature T_m=500–790 °C, and is maintained in this state for the period of time τ_m, at that, the T_m value should be below the maximum superheating temperature T_p, the T_m/T_p ratio is set from the condition, that the metastable state τ_g lifetime was more than cracking time τ_k, by the feedstock of temperature change mode T by time τ controlling by the given function T=f(τ), performing heating in two stages, preliminary and rapid heating, at that, at the first stage, the temperature increases from the initial value T₀ to temperature T₁, which lies below the feedstock boiling point beginning, but does not exceed its thermal stability temperature (350–360 °C), at the second stage, the feedstock is rapidly superheated to the metastable state during time from 0.5 to 5 times of the liquid medium's lifetime values in the given state, observing the τ_gτ_mτ_k condition. Heavy oil products thermal cracking unit includes the feedstock to the heating zone supply system, unit for the feedstock heating to the required temperature and ensuring its thermal cracking, the cracking process control device, unit for the remainder returning for the mixing with the feedstock stream, wherein for the cracking process in metastable state controlling, a device is used for the feedstock temperature change in time given mode controlling with the exit into the metastable states temperature range, functionally connected to the consisting of two units heating unit, preheating unit and the rapid heating unit, at that the preheating unit provides the feedstock heating to the temperature below the feedstock boiling point beginning, but not exceeding its thermal stability temperature, and in the rapid heating unit the feedstock is heated to the metastable state predetermined temperature.;EFFECT: enabling the possibility of increase in the thermal cracking processes efficiency and speed.;10 cl, 7 dwg, 1 tbl, 3 ex