The present disclosure provides processes and systems for heat integration in ethanol production. In one embodiment, a feed mixture is distilled with one or more distillation units to remove at least a portion of the water, and form a distillation unit bottom stream, a vaporous overhead stream, and a fusel oil stream. Molecular sieve units are regenerated by vacuum or a combination of vacuum and optionally a portion of the product stream to form one or more regenerate streams. A feed tank is configured to receive at least one selected from a condensed portion of the regenerate streams and a portion of a vaporous depressure stream, to form a feed stream. The energy contained in the depressure vapor is recovered by the depressure vapor contacting the feed tank and heating up at least one stream forwarded into the feed tank.

A method of producing aromatic hydrocarbons including: supplying a raw material stream to a C6 separation column, supplying an upper discharge stream from the C6 separation column to a first gasoline hydrogenation unit, and supplying a lower discharge stream from the C6 separation column to a C7 separation column; supplying an upper discharge stream from the C7 separation column to the first gasoline hydrogenation unit and supplying a lower discharge stream from the C7 separation column to a C8 separation column; separating benzene and toluene from a discharge stream from the first gasoline hydrogenation unit; removing a lower discharge stream from the C8 separation column and supplying an upper discharge stream from the C8 separation column to a second extractive distillation column; and separating styrene from a lower discharge stream from the second extractive distillation column and separating xylene from an upper discharge stream from the second extractive distillation column.

The present invention utilizes mechanical vapor compression and/or thermal vapor compression integrating compression loops across multiple process stages. A sequential network of compressors is utilized to increase the pressure and condensing temperature of the vapors within each process stage, as intra-vapor flow, and branching between process stages, as inter-vapor flow. Because the vapors available are shared among and between compressor stages, the number of compressors can be reduced, improving economics. Balancing vapor mass flow through incremental compressor stages which traverse multiple process stages by splitting vapors between compressor stages enables the overall vapor-compression system to be tailored to individual process energy requirements and to accommodate dynamic fluctuations in process conditions.

A slurry separator comprising a moving blade that wipes slurry oil onto a wall of the slurry separator for separating a recovered oil stream from a concentrated residue stream has the capability of maximizing recovery of the LCO from slurry oil as well as removing both the catalyst fines as well as coke particles suspended in the slurry oil. The slurry separator can be fed directly from the main column bottoms. Advantageously, the process and apparatus can enable the FCC unit to achieve higher production of LCO and higher value clarified slurry oil more efficiently.

A system and method for removing acetic acid and other short chain fatty acids described as organic acid from a rich mono-ethylene glycol (“MEG”) solution does so by stripping the organic acid from the rich MEG solution by contacting the solution with a gas, the gas being nitrogen or a fuel gas such as methane; and stripping the organic acid from the gas by contacting the gas with a caustic solution such as a dilute sodium hydroxide solution. The stripping takes place in respective stripping columns. A portion of the gas exiting the gas/organic acid stripping column can be recycled to the MEG/organic acid stripping column to reduce total gas usage. A portion of the waste stream exiting the gas/organic acid stripping column can be recycled back to the gas/organic acid stripping column to reduce the amount of caustic solution used as well as the amount of waste.

The present application relates to a distillation device, and according to the distillation device of the present application, in first and second compounds being capable of forming an azeotrope, by introducing the second compound having a relatively high boiling point into a supply port located below the first compound having a relatively low boiling point, the first compound can be previously separated from the top of a first distillation column and the content of the first compound in the flow discharged from the bottom of the first distillation column can be minimized, and thus, as a moving route of the first compound is minimized, the second compound can be separated in high purity.

A process and apparatus for producing a hydrogen-enriched product and recovering CO.sub.2 from an effluent stream from a hydrogen production process unit are described. The process utilizes a CO.sub.2 recovery system integrated with a PSA system that produces at least two product streams to recover additional hydrogen and CO.sub.2 from the tail gas stream of a hydrogen PSA unit in the hydrogen production process.

A process and apparatus for producing a hydrogen-enriched product and recovering CO.sub.2 from an effluent stream from a hydrogen production unit are described. The effluent from the hydrogen production unit, which comprises a mixture of gases comprising hydrogen, carbon dioxide, water, and at least one of methane, carbon monoxide, nitrogen, and argon, is sent to a PSA system that produces at least two product streams for separation. The PSA system that produces at least two product streams separates the gas mixture into a high-pressure hydrogen stream enriched in hydrogen, optionally a second gas stream containing the majority of the impurities, and a low-pressure tail gas stream enriched in CO.sub.2 and some impurities. The CO.sub.2-rich tail gas stream is compressed and sent to a CO.sub.2 recovery unit, where a CO.sub.2-enriched stream is recovered. The CO.sub.2-depleted overhead gas stream is recycled to the PSA system that produces at least two product streams.

A process for treating effluent streams in a renewable transportation fuel production process is described. One or more of the sour water stream and an acid gas stream are treated directly in thermal oxidation section. The process allows the elimination or size reduction of a sour water stripper unit, waste water treatment plant, and sulfur recovery unit.

In producing C.sub.2-C.sub.4 olefins, in particular propylene, from an educt mixture containing steam and oxygenates, such as methanol and/or dimethyl ether, the educt mixture is reacted in a reactor on a catalyst to a reaction mixture comprising low-molecular olefins and gasoline hydrocarbons, which in a first separating device is separated into a mixture rich in C.sub.5− olefins, a mixture rich in C.sub.5+ gasoline hydrocarbons, and an aqueous phase. To increase the yield of propylene the mixture rich in C.sub.5+ gasoline hydrocarbons is supplied to a second separating device, in which the aromatics contained in the mixture are separated. The residual stream largely free from aromatics is at least partly recirculated to the reactor.