Hydrocracked bottoms fractions are treated to separate HPNA compounds and/or HPNA precursor compounds and produce a reduced-HPNA hydrocracked bottoms fraction effective for recycle. A process for separation of HPNA and/or HPNA precursor compounds from a hydrocracked bottoms fraction of a hydroprocessing reaction effluent comprises contacting the hydrocracked bottoms fraction with heteropoly acid compounds to promote adsorption of HPNAs onto the heteropoly acids and to produce a heteropoly acid treated hydrocracked bottoms fraction, that is recycled within the hydrocracking operation.

An extractive distillation column system contains a combination column and a side rectification column. A process can be used for separation of butenes from C4-hydrocarbon streams using the extractive distillation column system.

Described and represented is a glycol drying system with at least one wet glycol collection container and/or at least one glycol collection line to collect moist glycol, with at least one heating device to heat the moist glycol in the at least one wet glycol collection container and/or in the at least one glycol collection line and with a membrane separation system to separate the water from the heated, moist glycol. In order to reduce the operating costs, without having to accept disproportionate investment costs, it is provided that at least one flash gas vent is provided to remove flash gas driven out when the moist glycol is heated before separating the water in the membrane separation system and in that at least one combustion chamber is provided to combust the flash gas and to provide heat for the heating device.

The present invention relates to a process for treating an effluent obtained from an oligomerization step in a vaporization step. In particular, the oligomerization step is a step for dimerization of ethylene to 1-butene with a nickel-based catalytic system.

Systems and methods are provided for improving the operation of a divided wall column for performing distillations. The systems and methods include using a separation stage in a fluid flow pathway for transporting an enriched intermediate stream from a first side of a dividing wall to a second side of a dividing wall. By using a separation stage, the benefit of transporting an enriched intermediate stream can be achieved without requiring precise knowledge of the local concentration profile on the first side of the dividing wall.

A process for hydrocracking a petroleum feedstock involves: (a) hydrocracking the feedstock to obtain a hydrocracked effluent; (b) liquid/gas separation of the effluent to obtain a gaseous effluent and a liquid effluent; (c) fractionating the liquid effluent at a pressure P1, producing a first distillate and a first residue, (d) recycling a first portion of the first residue to hydrocracking, (e) rectifying a second portion of the first residue at a pressure P2 lower than or equal to the pressure P1, to obtain a secondary distillate, a secondary residue and a vapor stream, (f) purging a portion of the secondary residue, and (g) recycling all or part of the secondary distillate to hydrocracking.

Provided is a method for preparing 1-butene and propylene including: supplying a C4 mixture stream to a first hydrogenation reactor to convert 1,3-butadiene into 1-butene; supplying a discharge stream from the first hydrogenation reactor to a first distillation column, supplying a lower discharge stream from the first distillation column including 2-butene and n-butane to a metathesis reactor, and supplying an upper discharge stream from the first distillation column including 1-butene and i-butane to a second distillation column; recovering an upper discharge stream the second distillation column including i-butane and recovering 1-butene from a lower discharge stream from the second distillation column; and producing propylene in the metathesis reactor, supplying a discharge stream from the metathesis reactor to a purification unit to recover propylene, and recycling an unreacted material to the metathesis reactor.

A method may include: providing bio waste stream wherein the bio waste stream comprises at least one bio waste selected from the group consisting of palm oil mill effluent, soapstock, and combinations thereof; introducing the bio waste effluent stream into a fluidized catalytic cracking unit; contacting the bio waste with a catalyst in the fluidized catalytic cacking unit; and cracking at least a portion of the bio waste stream to form cracked products that comprise a cracked product stream.

A method may include: providing bio waste stream wherein the bio waste stream comprises at least one bio waste selected from the group consisting of palm oil mill effluent, soapstock, and combinations thereof; introducing the bio waste effluent stream into a fluidized catalytic cracking unit; contacting the bio waste with a catalyst in the fluidized catalytic cacking unit; and cracking at least a portion of the bio waste stream to form cracked products that comprise a cracked product stream.

A combined plant for cryogenic separation and liquefaction of methane and carbon dioxide in a biogas stream, including a mixing means, a compressor, a first exchanger, a distillation column, a second exchanger, a separating means, an expanding means, and a separator vessel. Wherein, the mixing means is configured such that the recycle gas is the overhead vapour stream, and the first exchanger and the expanding means are combined.