The present invention describes a process for heating the reboiler of the propane/propylene separation column situated downstream of an FCC unit and fed with the C3 cut from said FCC unit, a process consisting of heating the water in a hot water circuit by means of one or more process fluids originating from units placed upstream and/or downstream of the FCC unit and called hot fluids, one of these fluids being constituted by the overhead vapours from the fractionation column connected to the mild hydrocracking unit.

A system and process that are configured to prepare incoming hydrocarbon feedstocks for storage. For incoming ethane gas, the embodiments can utilize a plurality of vessels to distill the incoming feedstock to vapor and liquid ethane that is suitable for storage. The embodiments can direct the vapor to a demethanizer column that is downstream of the vessels and other components. The process can include stages for distilling an incoming feedstock at a plurality of vessels to form a vapor and a liquid for storage; directing the vapor to a demethanizer column; and circulating liquid from the demethanizer column back to the plurality of vessels.

Provided are an apparatus and a method for separation and recovery of propane and heavier hydrocarbons from LNG. The apparatus has, from the upstream side toward the downstream side of LNG supply, first column (3) equipped with first column overhead condenser (2), first column bottom reboiler (4) and side reboiler (5), and second column (14) equipped with second column overhead condenser (11) and second column bottom reboiler (15). The first column (3) separates methane and a part of ethane as an overhead vapor and separates remaining ethane and C3 or higher hydrocarbons as a bottom liquid. The second column (14) separates ethane as an overhead vapor and separates C3 or higher hydrocarbons as a bottom liquid.

An improved method for separating hydrocarbons for separating feed LNG into product LNG and a liquid fraction enriched in C3+ components is provided. Feed LNG is heated and partially vaporized by a heat exchanger to obtain a vapor-liquid two-phase stream; the whole or a liquid phase of the vapor-liquid two-phase stream is separated into first overhead vapor enriched in methane and first bottom liquid enriched in ethane and C3+ components at a first distillation column; the first bottom liquid is separated into second overhead vapor enriched in ethane and second bottom liquid enriched in C3+ components by the second distillation column; the second overhead vapor is cooled and wholly or partially condensed to obtain condensed liquid; one of two or more streams obtained by dividing the condensed liquid is mixed with the first overhead vapor; the mixed stream is totally condensed to obtain a liquid stream by heat exchange with feed LNG by the heat exchanger; the whole or a part of the liquid stream is discharged as product LNG; another of the divided streams is refluxed to the second distillation column; and the second bottom liquid is discharged as the liquid fraction enriched in C3+ components.

Certain aspects of natural gas liquid fractionation plant waste heat conversion to simultaneous power and potable water using Kalina Cycle and modified multi-effect-distillation system can be implemented as a system. The system includes a waste heat recovery heat exchanger network coupled to multiple heat sources of a Natural Gas Liquid (NGL) fractionation plant. The heat exchanger network is configured to transfer at least a portion of heat generated at the multiple heat sources to a first buffer fluid and a second buffer fluid flowed through the first heat exchanger network. The system includes a first sub-system configured to generate power. The first sub-system is thermally coupled to the waste heat recovery heat exchanger. The system includes a second sub-system configured to generate potable water from brackish water. The second sub-system is thermally coupled to the waste heat recovery heat exchanger.

Certain aspects of natural gas liquid fractionation plant waste heat conversion to simultaneous power and potable water using organic Rankine cycle and modified multi-effect distillation systems can be implemented as a system that includes two heating fluid circuits thermally coupled to two sets of heat sources of a NGL fractionation plant. The system includes a power generation system that comprises an organic Rankine cycle (ORC), which includes (i) a working fluid that is thermally coupled to the first heating fluid circuit to heat the working fluid, and (ii) a first expander configured to generate electrical power from the heated working fluid. The system includes a MED system thermally coupled to the second heating fluid circuit and configured to produce potable water using at least a portion of heat from the second heating fluid circuit. A control system actuates control valves to selectively thermally couple the heating fluid circuit to a portion of the heat sources of the NGL fractionation plant.

A gas plant using an Ortloff or similar process comprising the use of a second expander in place of a valve used in most demethanizer reflux systems, wherein a compressor wheel is used to increase the pressure of the partial stream of inlet gas that is used to provide heat to the demethanizer reboilers. This stream remains a separate stream and is used for the flow of gas that feeds the demethanizer reflux expander.

The invention relates to various nonlimiting embodiments that include methods, apparatuses or systems for processing natural gas comprising a heavies removal column processing natural gas and light oil reflux. The overhead stream goes to heavies treated natural gas storage. The heavies removal column reboiler bottoms stream product is input to a debutanizer column. The debutanizer column overhead lights are input to a flash drum where the bottoms is pumped through a heat exchanger as a light oil reflux input to the heavies removal column, while the debutanizer reboiler bottoms product is stored as stabilized condensate. Alternatively, debutanizer column overhead lights are sent to heavies treated gas storage and the bottoms stream product goes to a depentanizer column, the overhead lights are pumped through a heat exchanger as a light oil reflux input to the heavies removal column, while the depentanizer reboiler bottoms product is stabilized condensate.

A system and method for enhancing propane recovery in a GSP system operated in an ethane rejection mode using an add-on system comprising a heat exchanger and a condenser and optionally a reflux column having 0-5 theoretical stages. An overhead stream from a GSP fractionation column and a subcooled expanded GSP stream are diverted from the typical GSP process for processing in the add-on system to provide an additional reflux stream that increases the amount of ethane and propane that feeds into a top level of the GSP fractionation column. In ethane rejection mode, the add-on system results in an NGL product stream preferably comprising less than 6% of the ethane and at least 97% of the propane from the GSP feed stream.

The invention relates to a system, method and apparatus for removing heavies from natural gas. Natural gas and an external rich reflux gas feed are processed in a single column refluxed absorber. A bottoms stream is routed to a first heat exchanger and then to a stabilizer column where an overhead stream from the stabilizer column is routed through a condenser for partial separation into an overhead stream. A rich solvent may be introduced to the stabilizer column. The overhead stream is routed through a condenser for partial separation into a stabilizer reflux and a second overhead stream lights. The second overhead stream lights is routed to a heat exchanger and then routed to a partial condenser where the stream is separated into a heavies rich reflux stream, a distillate stream and heavies treated natural gas stream. The rich reflux is routed through a heat exchanger and the rich reflux is pumped to the single column refluxed absorber to be introduced into the single column refluxed absorber as the external rich reflux gas feed.