PROCEDE DE VAPOCRAQUAGE FLEXIBLE ET INSTALLATION DE VAPOCRAQUAGE CORRESPONDANTE

摘要

A flexible steam cracking method for steam cracking hydrocarbon feedstocks by injecting particles with an average size of 0.02-4 mm at at least one point upstream from an indirect quenching exchanger (4) without separating the cracking region (2) from means (6) provided downstream for processing the cooled effluents, said particles being injected with a circulation speed in the indirect quenching means (4) of 20-180 m/s and in an amount sufficient to limit the increase in the exit temperature of the means (4) to a value of less than 100 DEG C per month. At least 70 % of the injected particles are fed in between the outlet of the cracking region (2) and the tubes of the indirect quenching exchanger (4). The tube cracking region is chemically decoked at intervals of less than 4 months by creating accelerated coke gasification conditions, e.g. by injecting steam gasification catalyst compounds, or by air and/or steam decoking.