The raw materials used in thermal cracking processes include ethane, propane and butane, liquid naphtha and diesel. Thermal cracking, pyrolysis, with water vapor is a good way to convert inactive paraffinic hydrocarbons to olefin active compounds, which are the main feed for the petrochemical industry. Steam cracking furnaces are process units, devoted to producing ethylene and propylene from a stream of hydrocarbons and steam. Today’s modern ethylene plants are complex networks of more than 300 individual units, including thermal cracking, cracked gas compression and physical scrubbing, fractionation, adsorptive drying, catalytic hydrogenation and others, operating in the temperature range of 1100☌ to −170☌.

ethane, propane and butane) are recycled to the furnaces in order to improve overall yields. The compressed, cracked gas is then separated into specified products. Later the process steam is condensed and removed from the cracked gas before it enters the compression and chilling sections (Cold Section). The separation train of a cracker starts with the Hot Section and then the cracked gas is quenched and cooled where heavy fractions are condensed and separated. The resulting gas is separated into valuable products suitable for downstream processes. The heavy hydrocarbon compounds are usually cracked at temperatures between 800☌ and 860☌. It is the principal industrial method for producing the lighter alkenes commonly known as olefins, including ethene or ethylene, propene or propylene and butadiene. Olefin production is a petrochemical process in which saturated hydrocarbons are broken down into smaller, often unsaturated ones. Olefin plants are large, complex units at the heart of petrochemical complexes.

Petrochemical processes handbook pdf