A process for producing light olefins comprising thermal cracking. Hydrocracked streams are thermally cracked in a steam cracker to produce light olefins. A pyrolysis gas stream is separated into a light stream and a heavy stream. A light stream is separated into an aromatic naphtha stream and a non-aromatic naphtha stream. The aromatics can be saturated and thermally cracked. The integrated process may be employed to obtain olefin products of high value from a crude stream.

A process for producing light olefins comprising thermal cracking. Hydrocracked streams are thermally cracked in a steam cracker to produce light olefins. A pyrolysis gas stream is separated into a light stream and a heavy stream. A light stream is separated into an aromatic naphtha stream and a non-aromatic naphtha stream. The aromatics can be saturated and thermally cracked. The integrated process may be employed to obtain olefin products of high value from a crude stream.

A method and apparatus for processing a hydrocarbon stream are described. The method includes heating a feed stream in a convective bank. The heated feed stream is reacted in a first reaction zone to form a first effluent, which is heated in a first radiant cell. The first radiant cell combusts fuel to heat the first effluent and forms a first exhaust gas. The first exhaust gas is contacted with the convective bank to heat the feed stream. The outlet temperature the heated feed stream from the convective bank is controlled by introducing an additional gas stream into the convective bank. There can be additional reaction zones and radiant heaters.

Provided is a continuous process for converting waste plastic into a feedstock for polyethylene polymerization. The process comprises selecting waste plastics containing polyethylene and/or polypropylene, and then passing the waste plastics through a pyrolysis reactor to thermally crack at least a portion of the polyolefin waste and produce a pyrolyzed effluent. The pyrolyzed effluent is then separated into offgas, a pyrolysis oil comprising a naphtha/diesel/heavy fraction, and char. The pyrolysis oil is passed to a crude unit in a refinery from which a naphtha fraction (C.sub.5-C.sub.8), or a propane and butane (C.sub.3-C.sub.4) fraction, is recovered. The naphtha fraction, or propane and butane (C.sub.3-C.sub.4) fraction, is then passed to a steam cracker for ethylene production.

Provided is a continuous process for converting waste plastic into a feedstock for polyethylene polymerization. The process comprises selecting waste plastics containing polyethylene and/or polypropylene, and then passing the waste plastics through a pyrolysis reactor to thermally crack at least a portion of the polyolefin waste and produce a pyrolyzed effluent. The pyrolyzed effluent is then separated into offgas, a pyrolysis oil comprising a naphtha/diesel/heavy fraction, and char. The pyrolysis oil is passed to a crude unit in a refinery from which a naphtha fraction (C.sub.5-C.sub.8), or a propane and butane (C.sub.3-C.sub.4) fraction, is recovered. The naphtha fraction, or propane and butane (C.sub.3-C.sub.4) fraction, is then passed to a steam cracker for ethylene production.

Provided is a continuous process for converting waste plastic into recycle for polypropylene polymerization. The process comprises selecting waste plastics containing polyethylene and/or polypropylene and passing the waste plastics through a pyrolysis reactor to thermally crack at least a portion of the polyolefin waste and produce a pyrolyzed effluent. The pyrolyzed effluent is separated into offgas, a naphtha/diesel fraction, a heavy fraction, and char. Pyrolysis oil and wax, comprising the naphtha/diesel fraction and heavy fraction, is sent to a refinery FCC unit. A liquid petroleum gas C.sub.3-C.sub.5 olefin/paraffin mixture is recovered from the FCC unit and passed to a refinery alkylation unit. A propane fraction is recovered from the alkylation unit and passed to a dehydrogenation unit to produce propylene. The propylene is passed to a propylene polymerization reactor.

Provided is a continuous process for converting waste plastic into recycle for polypropylene polymerization. The process comprises selecting waste plastics containing polyethylene and/or polypropylene and passing the waste plastics through a pyrolysis reactor to thermally crack at least a portion of the polyolefin waste and produce a pyrolyzed effluent. The pyrolyzed effluent is separated into offgas, a naphtha/diesel fraction, a heavy fraction, and char. Pyrolysis oil and wax, comprising the naphtha/diesel fraction and heavy fraction, is sent to a refinery FCC unit. A liquid petroleum gas C.sub.3-C.sub.5 olefin/paraffin mixture is recovered from the FCC unit and passed to a refinery alkylation unit. A propane fraction is recovered from the alkylation unit and passed to a dehydrogenation unit to produce propylene. The propylene is passed to a propylene polymerization reactor.

Provided in one embodiment is a continuous process for converting waste plastic into recycle for polyethylene polymerization. The process comprises selecting waste plastics containing polyethylene and/or polypropylene, and passing the waste plastics through a pyrolysis reactor to thermally crack at least a portion of the polyolefin waste and produce a pyrolyzed effluent. The pyrolyzed effluent is separated into offgas, a pyrolysis oil and optionally wax comprising a naphtha/diesel and heavy fraction, and char. The pyrolysis oil is passed to a refinery FCC unit from which a liquid petroleum gas C.sub.3 olefin/paraffin mixture fraction is recovered, as well as a C.sub.4 olefin/paraffin mixture fraction. The liquid petroleum gas C.sub.3 olefin/paraffin mixture fraction is passed to a steam cracker for ethylene production. The C.sub.4 olefin/paraffin mixture fraction is passed to a refinery alkylation unit, from which a n-butane and naphtha feed for a stream cracker to produce ethylene is recovered.

Provided in one embodiment is a continuous process for converting waste plastic into recycle for polyethylene polymerization. The process comprises selecting waste plastics containing polyethylene and/or polypropylene, and passing the waste plastics through a pyrolysis reactor to thermally crack at least a portion of the polyolefin waste and produce a pyrolyzed effluent. The pyrolyzed effluent is separated into offgas, a pyrolysis oil and optionally wax comprising a naphtha/diesel and heavy fraction, and char. The pyrolysis oil is passed to a refinery FCC unit from which a liquid petroleum gas C.sub.3 olefin/paraffin mixture fraction is recovered, as well as a C.sub.4 olefin/paraffin mixture fraction. The liquid petroleum gas C.sub.3 olefin/paraffin mixture fraction is passed to a steam cracker for ethylene production. The C.sub.4 olefin/paraffin mixture fraction is passed to a refinery alkylation unit, from which a n-butane and naphtha feed for a stream cracker to produce ethylene is recovered.

A process and a system for reforming and upgrading a heavy naphtha feedstock may include dehydrogenating naphthenes in the heavy naphtha feedstock to form a first effluent stream comprising aromatics and then separating the aromatics via extraction from the produced first effluent stream to produce a second effluent stream containing raffinate paraffins. The process may then include subjecting the second effluent stream to cyclization reactions to produce a third effluent stream comprising aromatics and then combining the first effluent stream and the third effluent stream prior to extraction.