Process for separating and recovering NGLs from hydrocarbon streams

摘要

This process comprises using unconventional processing of hydrocarbons, e.g. natural gas, for recovering C2+ and NGL hydrocarbons that meet pipeline specifications, without the core high capital cost requirement of a demethanizer column, which is central to and required by almost 100% of the world's current NGL recovery technologies. It can operate in Ethane Extraction or Ethane Rejection modes. The process uses only heat exchangers, compression and simple separation vessels to achieve specification ready NGL. The process utilizes cooling the natural gas, expansion cooling, separating the gas and liquid streams, recycling the cooled streams to exchange heat and recycling selective composition bearing streams to achieve selective extraction of hydrocarbons, in this instance being NGLs. The compactness and utility of this process makes it feasible in offshore applications as well as to implementation to retrofit/revamp or unload existing NGL facilities. Many disparate processes and derivatives are anticipated for its use.

主权项

1. A process for separating less volatile hydrocarbons from more volatile hydrocarbons while also producing stabilized condensates or NGL, comprising the steps of:
a. providing a pressurized feedstock stream comprising hydrocarbons; b. directing the feedstock stream as a feed stream to a heat exchanger and then cooling the feed stream in the heat exchanger; c. further cooling the feed stream from the heat exchanger via a first gas expansion assembly; d. directing the further cooled stream from the first gas expansion assembly to a first gas/liquid mixer and separation vessel assembly and separating the further cooled stream into gas and liquid streams, wherein the first gas/liquid mixer and separation vessel assembly is capable of receiving one or more recycle streams from one or more downstream processing steps; e. directing the liquid stream from the first gas/liquid mixer and separation vessel assembly to a splitter pump capable of directing fractions of the liquid stream from the splitter pump to the heat exchanger and to a third stream splitter; f. recycling a fraction of the liquid stream from the splitter pump into the heat exchanger to provide cooling to the feed stream in the heat exchanger, and directing the balance of the liquid stream from the first gas/liquid mixer and separation vessel assembly to the third stream splitter; g. recycling the gas stream from the first gas/liquid mixer and separation vessel assembly into the heat exchanger to impart additional cooling in the heat exchanger; h. directing the recycled gas stream from the heat exchanger to a first compressor cooler assembly, and then compressing and cooling the recycled gas stream for use at an end location; i. directing the recycled liquid stream from the heat exchanger to a second separation vessel assembly wherein gas and liquid are separated; j. directing the gas stream from the second separation vessel assembly to a second compressor cooler assembly and compressing the gas stream from the second separation vessel assembly; k. cooling the gas stream from the second compressor cooler assembly via a second gas expansion assembly; l. directing the cooled stream from the second gas expansion assembly to a third separation vessel assembly wherein gas and liquid are separated, wherein the third separation vessel assembly is capable of directing fractions of the liquid stream in the third separation vessel assembly to the first gas/liquid mixer and separation vessel assembly, a first stream mixer splitter assembly, and/or the second separation vessel assembly, and wherein the third separation vessel assembly is capable of directing fractions of the gas stream (totaling 100%) in the third separation vessel assembly to the first gas/liquid mixer and separation vessel assembly and/or to the first stream mixer splitter assembly; m. directing a fraction of the gas stream from the third separation vessel assembly to the first gas/liquid mixer and separation vessel assembly; n. directing a fraction of the gas stream from the third separation vessel assembly to the first stream mixer splitter assembly;
wherein the combined fractions of step m. and step n. total 100%; o. directing a desired fraction of the liquid stream from the third separation vessel assembly to the first gas/liquid mixer and separation vessel assembly; p. directing a desired fraction of the liquid stream from the third separation vessel assembly to the first stream mixer splitter assembly; q. directing a desired fraction of the liquid stream from the third separation vessel assembly to the second separation vessel assembly;
wherein the combined fractions of step o., step p. and step q. total 100%; r. pumping the liquid stream from the second separation vessel assembly to the first stream mixer splitter assembly; s. directing a first fraction of a stream from the first stream mixer splitter assembly to a mixing blender or other end location; t. directing a fraction of the stream from the first stream mixer splitter assembly to a second stream mixer splitter assembly; u. directing a first fraction of a stream from the second stream mixer splitter assembly to the mixing blender or other end location; v. pumping the fraction of the liquid stream from the first gas/liquid mixer and separation vessel assembly to the third stream splitter via the splitter pump, the third stream splitter capable of directing fractions of the liquid stream from the third stream splitter to the first gas/liquid mixer and separation vessel assembly, a fourth stream splitter, and/or to an end location; w. directing a first fraction of a liquid stream from the third stream splitter to the first gas/liquid mixer and separation vessel assembly; x. directing a second fraction of the liquid stream from the third stream splitter to the fourth stream splitter, the fourth stream splitter being capable of directing fractions of a liquid stream from the fourth stream splitter to the third separation vessel assembly and/or the second separation vessel assembly; y. directing a third fraction of the liquid stream from the third stream splitter to an end location;
wherein the combined fractions of step w., step x. and step y. total 100%; z. directing a first fraction of the liquid stream from the fourth stream splitter to the third separation vessel assembly; aa. directing a second fraction of the liquid stream from the fourth stream splitter to the second separation vessel assembly;
wherein the combined fractions of step z. and step aa. total 100%; and bb. directing a stream from the mixing blender to an end location.