The petrochemicals industry is witnessing enormous growth worldwide. Ethylene is produced by cracking a range of hydrocarbons. Naphtha is the main raw material used in European and Japanese crackers, while the US utilizes ethane as its primary feedstock. In the US, 52% of ethylene is produced from ethane, 22% from gasoil, 5% from naphtha, and the remainder is from other feedstocks. In Western Europe, naphtha constitutes approximately 71% of ethylene feedstock, gasoil and LPG account for 11% each, and the remainder of ethylene production originates from ethane cracking. ETHYLENE PRODUCTION TECHNOLOGIESThe following is a review on the most common technologies for producing ethylene from different feedstocks. A summary of each technology, along with standard reactions, is presented, as well as temperatures/pressures of the reactions, operation of the reactors and whether the reaction type is endothermic or exothermic. Ethylene from steam cracking. The hydrocarbon stream is heated and then diluted by mixing it with steam before entering a tubular reactor when mass flow trough flow meter fill rite. The steam required depends on the type of feedstock used. The cracking reaction takes place at a temperature of 750°C–870°C under partial pressure, with a residence time of up to one second. The reaction (Eq. 1) is endothermic and requires considerable heat input C2H6 → C2H4 + H2 ... ( 1 )Ethylene from ethyl alcohol by dehydrogenation. Ethyl alcohol is changed into a vapor by heating it with a high–pressure steam before passing it over a fixed bed of activated alumina and phosphoric acid contained in the reactor, shown in Eq. 3. The reactor can be in either an isothermal or adiabatic state. The temperature ranges from 296°C–315°C, and conversion rates up to 99% are claimed, with a yield of 94%. 2C₂H₅OH → 2C₂H₄ +2H₂O ... ( 2 )Product range and yield. The choice of feedstock and the reaction cracking conditions determine the ratio of products obtained. The methodology used combines both the simulation (through an industrial process simulator program) and the cost model (through an economical evaluation of different technologies) for the production of ethylene based on the total investment cost in flow meter indonesia. The feedstocks used in this study for the production of ethylene and propylene were ethane (C2H6), propane (C3H8) and light naphtha.
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