A method for quenching a pyrolysis product, including: supplying a discharge stream from a liquid decomposition furnace to a first quench tower; supplying an upper discharge stream from the first quench tower to a second quench tower; supplying a discharge stream from a first gas decomposition furnace to the second quench tower; and supplying a discharge stream from a second gas decomposition furnace to the second quench tower.

A system includes a first separator that separates water from a fluid material. The water settles on the bottom of the water knock-out tank. The system includes multiple compressors to boost the pressure of the fluid material. The system includes a second separator that separates condensate from the fluid material. The system includes a mixing pipe that mixes glycol with the fluid material and a first heat exchanger that cools the mixed fluid material and glycol. The system includes a third separator that separates gaseous components and liquid components of the mixed fluid material and glycol and a fourth separator that separates the liquid components of the mixed fluid material and glycol. The system includes a fractional distillation column that heats a first liquid from the fourth separator, gasifying a first portion of the first liquid. A second portion of the first liquid remains liquid and is natural gas liquids.

A method for quenching a pyrolysis product, including: supplying a discharge stream from a liquid decomposition furnace to a first quench tower; supplying an upper discharge stream from the first quench tower to a second quench tower; supplying a discharge stream from a first gas decomposition furnace to the second quench tower; and supplying a discharge stream from a second gas decomposition furnace to the second quench tower.

A process for hydrocracking a hydrocarbon feed is provided. The process comprises hydrocracking the hydrocarbon feed to produce a first hydrocracking product stream, separating the first hydrocracking product stream to form a gas stream and a liquid stream, hydrocracking the liquid stream to produce a second hydrocracking product stream, separating the second hydrocracking product stream to form a first light stream and a first heavy stream comprising benzene, toluene, xylene, C.sub.9+ hydrocarbon, or a combination comprising at least one of the foregoing, purifying the gas stream to form a purified gas stream, and separating the purified gas stream to form at least two of a hydrogen stream, C.sub.1 stream, C.sub.2 stream, C.sub.3 stream, C.sub.4 stream, C.sub.5+ stream, or a combination comprising at least one of the foregoing.

A method for separating a hydrogen-containing hydrocarbon mixture (C2minus), which in addition to the hydrogen essentially contains hydrocarbons with two carbon atoms and methane, using a distillation column (10). Fluid (a, c, e) of the hydrocarbon mixture (C2minus) is cooled stepwise at a first pressure level, during which time first condensates (b, d) are separated from the fluid (a, c, e). Fluid (e) from the hydrocarbon mixture (C2minus) which remains gaseous after this is fed at the first pressure level into a C2 absorber (7), to which a liquid reflux (r) is added at the top, while a second condensate (f) is drawn off from the sump of the C2 absorber (7) and a gaseous top stream (g) containing predominantly methane and hydrogen is drawn off at the top of the C2 absorber (7). Fluid of the above-mentioned gaseous top stream (g) from the top of the C2 absorber (7) is cooled to a third temperature level and transferred at the first pressure level into a hydrogen separator (8) in which a methane-rich third condensate (i) is separated from the fluid of the gaseous top stream (g), leaving behind a gaseous, hydrogen-rich stream (h). Fluid of the first condensates (b, d) and fluid of the second condensate (f) is depressurized from the first pressure level to a second pressure level below the first pressure level and fed into the distillation column (10) which is operated at the second pressure level. Fluid (e) of the third condensate (i) which is separated in the hydrogen separator (8) from the fluid of the gaseous top stream (g) from the top of the C2 absorber is used as the reflux (r) added at the top of the C2 absorber (7) and transferred from the hydrogen separator to the C2 absorber solely by gravity. The invention also relates to a corresponding separating unit and a corresponding olefin apparatus.

A compression stage for the compression of cracked gas, the compression stage comprising a liquid separating means for separating liquid components from gaseous components of a cracked gas, a compressor connected to the liquid separating means, a gas cooling means connected to the compressor for cooling the compressed gas from the compressor, wherein the gas cooling means are cooled by a first cooling fluid from the cooling fluid source. The stage further comprises gas precooling means connected to the liquid separating means cracked gas, having an inlet for receiving the cracked gas.

The present invention relates to a method for treating a cracked stream stemming from a fluid catalytic cracker unit (FCCU) in order to improve propylene recovery. The present invention also relates to the corresponding installation to implement the method.

The invention relates to a process for separating a component mixture (K) comprising hydrogen, methane, hydrocarbons having two carbon atoms and hydrocarbons having three or more carbon atoms, wherein in a deethanization at least a portion of the component mixture (K) is subjected to a first partial condensation by cooling from a first temperature level to a second temperature level at a first pressure level to obtain a first gas fraction (G1) and a first liquid fraction (C1), at least a portion of the first gas fraction (G1) is subjected to a second partial condensation by cooling from the second temperature level to a third temperature level at the first pressure level to obtain a second gas fraction (G4) and a second liquid fraction (C2), and at least a portion of the first liquid fraction (C1) and at least a portion of the second liquid fraction (C2) are subjected to a rectification to obtain a third gas fraction (G3) and a third liquid fraction (C3+). The first liquid fraction (C1) or its part subjected to the rectification and the second liquid fraction (C2) or its part subjected to the rectification are expanded to a second pressure level and the rectification is carried out at the second pressure level, the first pressure level being 25 to 35 bar and the second pressure level being 14 to 17 bar. An overhead gas formed during the rectification is cooled to 25 to 35 C. and partially condensed, wherein a condensed portion of the overhead gas is used partially or completely as a reflux in the rectification and an uncondensed portion of the overhead gas is provided partially or completely as the third gas fraction (G3). The present invention likewise provides a corresponding plant (100, 200).

The present subject matter relates generally to processes for propylene recovery. More specifically, the present subject matter relates to processes for enhanced recovery of propylene and liquid petroleum gas (LPG) from the fuel gas produced in fluid catalytic cracking (FCC) units by minimizing the light ends and propylene in the unstabilized gasoline which is used as lean oil for the primary absorber of the FCC gas concentration unit.

This method comprises: forming an expanded intermediate recirculation stream (170) from a liquid (112, 128) obtained during an upstream cooling and/or intermediate cooling step, upstream from the downstream cooling step; circulating the intermediate recirculation stream (170) at least in an upstream heat exchanger (42) to cool an upstream stream of cracked gas (102); reintroducing the reheated intermediate recirculation stream (170) in a raw cracked gas (20) upstream from at least one compressor (36, 38) of a cooling and compression stage (24). The upstream, intermediate and downstream cooling steps is carried out without a heat exchanger respectively of an upstream stream of cracked gas (102), an intermediate stream of cracked gas (114) and a downstream stream of cracked gas (140) with an external refrigeration cycle.