Abstract:
The invention involves a process for treating a gas stream from a hydroprocessor that contains hydrogen, methane and C2+ hydrocarbons. In embodiments of the invention, the gas stream is sent through at least two pressure swing adsorption units to produce a high quality hydrogen stream, a fuel gas stream containing most of the methane and a tail gas stream that is sent to a steam cracker. Lean gas from a gas plant and other refinery off gases may also be processed together with the gas stream from the hydroprocessor.
Abstract:
Methods and apparatuses for processing hydrocarbon streams are provided. In an embodiment, a method for processing a hydrocarbon stream includes heating a feed stream in a convective bank. In the method, the feed stream is reacted in a first reaction zone to form a first effluent. The first effluent is heated in a first radiant cell that combusts fuel gas to heat the first effluent and forms a first exhaust gas. The method includes contacting the first exhaust gas with the convective bank to heat the feed stream.
Abstract:
A process for separation and treatment of a naphtha feedstock to increase overall octane in a gasoline blending pool by reducing or removing the normal pentane in the feedstock. The feedstock is passed into a divided wall column having an undivided top portion, an undivided bottom portion and a wall dividing a middle portion into two sections. The intermediate faction can include either all normal pentane, which can be utilized on other processes, or it can include a mixture of normal pentane and C6 hydrocarbons, which can be isomerized in an isomerization zone to increase the octane and then passed to a gasoline blending pool.
Abstract:
A process for recovering heat from the separation of hydrocarbons. The overhead vapor stream from a fractionation column is passed to a two stage heat pump compressor. The first stage of compression is used to reboil the fractionation column. The second stage is compressed and cooled passed to a separation zone. The liquid in the separation zone may be passed back to the fractionation column as secondary reflux, and/or recovered as liquid product. Heat may also be removed from the second stage. A suction drum on the first stage may be used to protect the heat pump compressor from any droplets in the overhead stream.
Abstract:
One exemplary embodiment can be a process for treating a hydroprocessing fraction. The process can include obtaining a bottom stream from a fractionation zone, and passing at least a portion of the bottom stream to a film generating evaporator zone for separating a first stream containing less heavy polynuclear aromatic compounds than a second stream.
Abstract:
A process and apparatus provides for blending a heavy naphtha stream with a diesel stream to increase the yield of diesel. The diesel stream is recovered separately from a kerosene stream to leave the kerosene stream undiminished. The blended diesel provides a valuable composition.
Abstract:
A composition for a mixed refrigerant can be used to efficiently separate hydrogen from light hydrocarbons. The mixed refrigerant can comprise about 0 to about 7 mol % inert gas, about 11 to about 35 mol % methane, about 25 to about 40 mol % C2 hydrocarbon, about 20 to about 50 mol % C3 hydrocarbon and about 0 to about 15 mol % C5 hydrocarbon.
Abstract:
A process and apparatus integrate a deethanizer column with a cryogenic heat exchanger by reboiling the deethanizer column with a refrigerant stream and/or cooling a deethanizer overhead line in the cryogenic heat exchanger. A single stage separator and a single deethanizer column may be used to obtain high purity hydrogen in the net gas stream and an ethane rich off-gas stream, whereas conventionally a dual stage separator and two deethanizer columns were necessary for equivalent purity, respectively.
Abstract:
Embodiments of apparatuses and methods for reforming of hydrocarbons including recovery of products are provided. In one example, a method comprises separating a reforming-zone effluent into a net gas phase stream and a liquid phase hydrocarbon stream. The net gas phase stream is separated for forming an H2-rich stream and a first liquid phase hydrocarbon stream. The H2-rich stream may be contacted with an adsorbent to form an H2-ultra rich stream and a gas stream. C3/C4 hydrocarbons are absorbed from the gas stream with the liquid phase hydrocarbon stream. The gas stream may be contacted with an H2/hydrocarbon separation membrane to separate the PSA tail gas stream and form an H2-rich permeate stream and an H2 depleted non-permeate residue stream.
Abstract:
The process produces a diesel stream from a biorenewable feedstock by hydrotreating to remove heteroatoms and saturate olefins. The recycle gas is recycled to the hydrotreating reactor without removing hydrogen sulfide, which is needed in the biorenewable feed to keep the hydrotreating catalyst active. A purification unit can be utilized on a purge gas stream to purify the gas and improve hydrogen concentration in the recycle gas when added to the recycle gas.