A plant for separating at least one purified hydrocarbon stream from at least one crude hydrocarbon feed stream. The plant comprises a vessel with a single foundation. The vessel comprises an absorber section and a first divided-wall column. The first divided-wall column comprises a dividing wall, a stripper section, and a stabilization section.

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.

Processes and systems for making recycle content hydrocarbons, including olefins, from recycled waste material. Recycle waste material may be pyrolyzed to form recycle content pyrolysis oil composition (r-pyoil), at least a portion of which may then be cracked to form a recycle content olefin composition (r-olefin). The r- olefin may then be further separated into product streams in a separation zone downstream of the cracker furnace. In some cases, presence of recycle content hydrocarbons may facilitate more efficient operation of one or more distillation columns in the separation zone, including the demethanizer.

A system for hydrogenation C.sub.3 and C.sub.4 acetylenes contained within a hydrocarbon stream generated in a stream cracker unit where a debutanizer is placed upstream of a depropanizer for more economical processing of the hydrocarbon stream to produce lighter hydrocarbons, where the system requires only one stripper tower downstream of hydrogenation to remove residual hydrogen.

This method comprises passing a residual stream into a flash drum to form a gaseous overhead flow and liquid bottom flow, and feeding the bottom flow into a distillation column, It comprises cooling the overhead flow in a heat exchanger to form a cooled overhead flow. It comprises the extraction of a gaseous overhead stream at the head of the distillation column, and the formation of at least one effluent stream from the overhead stream and/or from the top stream. The separation of the cooled overhead flow comprises passing the cooled overhead flow into an absorber, and injecting a methane-rich stream into the absorber to place the cooled overhead flow in contact with the methane-rich stream.

Systems and processes for detecting leaks into a refrigeration system having a heat exchanger where the process side is configured to operate at a higher pressure than the refrigerant side. The system includes a refrigerant circulation system including a refrigerant feed pipe fluidly connected to and configured to provide a refrigerant to an inlet of the refrigerant side of the heat exchanger, as well as a refrigerant effluent pipe fluidly connected to and configured to receive a refrigerant from an outlet of the refrigerant side of the heat exchanger. One or more sensors are provided, the sensors being configured to measure a property of the refrigerant, such as temperature, pressure, or flow rate, for example. Additionally, the system for detecting leaks includes a digital control system configured to provide an alert when a signal from at least one of the one or more sensors is indicative of a leak from the process side of the heat exchanger to the refrigerant side of the heat exchanger.

This invention provides a fluidized catalytic cracking apparatus and process for converting a hydrocarbon feedstock containing higher concentrations of Conradson Carbon Residue (CCR), metal impurities, etc into lighter products by employing two riser reactors in which the feed impurities are removed using an adsorbent in a first riser reactor and cracking a portion of first riser reactor liquid product in a second riser reactor to lighter products using the active catalyst thus eliminating the catalyst deactivation due to metal, impurities and FCC catalyst activity dilution effect to achieve a better conversion and higher catalyst longevity.

Provided is a method for treating an oil gas, which can realize high-efficiency separation for and recovery of gasoline components, C.sub.2, C.sub.3, and C.sub.4 components. The method first conducts separation of light hydrocarbon components from gasoline components, and then performs subsequent treatment on a stream rich in the light hydrocarbon components, during which it is no longer necessary to use gasoline to circularly absorb liquefied gas components, which significantly reduces the amount of gasoline to be circulated and reduces energy consumption throughout the separation process. Besides, in this method, impurities, such as H.sub.2S and mercaptans, in the stream rich in the light hydrocarbon components are removed first before the separation for the components. This ensures that impurities will not be carried to a downstream light hydrocarbon recovery section, thus avoiding corrosion issues caused by hydrogen sulfide in the light hydrocarbon recovery section.

A method for separating and refining 1-butene with a high purity and a high yield from a raffinate-2 stream. The method includes: feeding raffinate-2 to a first distillation column; obtaining heavy raffinate-3 from a lower part of the first distillation column; recovering an upper part fraction containing 1-butene from an upper part of the first distillation column; feeding the upper part fraction containing 1-butene to a second distillation column; recovering a first lower part fraction rich in 1-butene from a lower part of the second distillation column and light raffinate-3 from an upper part of the second distillation column. Heat of the upper part fraction recovered from the upper part of the first distillation column is fed to the lower part of the second distillation column through a first heat exchanger. Thus, 1-butene is obtained with high purity and high yield while maximizing an energy recovery amount by double-effect distillation.

A plastic pyrolysis process produces light olefin product and heavier products. The light olefin products are separated in a recovery process while the heavier product can be sent to a cracking unit to be further cracked to desired products. The cracked effluent stream may be subjected to the recovery process along with the light olefin product.