Installation (plant) for thermo-cracking a hydrocarbon starting material to alkene, shell and tube heat exchanger for use in such an installation and process for manufacturing shell and tube heat exchanger

摘要

The invention relates to an installation (plant) for thermocracking a hydrocarbon starting material to alkenes, comprising a cracking furnace with externally heated reactor tubes (coils) and a shell and tube heat exchanger («quench», cooler, «transfer line» heat exchanger, TLX) to be used for quenching the reactor effluent and connected to the cracking furnace, wherein on the shell side steam is generated, wherein the internal surface of the tubes of the heat exchanger is coated with an inert layer impermeable to the materials in the reactor effluent which are responsible for the fouling, said layer masking the alloy of which the heating exchanger tubes consist. Said layer has a thickness of preferably 0.5 - 20 pm and is a layer based on an inert metal, in particular aluminium, metal oxide, aluminate, silicate or graphite or is an inert polymeric layer, in particular a layer formed by thermosetting alkylene quench oil with a peroxide, like benzoyl peroxide. The invention also relates to the heat exchanges.