Downhole fluid separator in lateral of re-entry multilateral well

A system comprising:

• a fluid separator disposed within a lateral bore of a multilateral well, wherein the fluid separator is configured to receive formation fluid that is produced via a lower completion assembly disposed in a main bore of the multilateral well and separate the formation fluid into formation water and production fluid, wherein the fluid separator is configured to output the production fluid to flow uphole wherein the fluid separator comprises:
• a separator housing;
• a fluid inlet formed in the separator housing, wherein the fluid inlet is disposed at an uphole end of the separator housing, wherein the fluid inlet is configured to receive the formation fluid from the main bore of the multilateral well;
• an elongated fluid chamber formed in the separator housing, wherein the formation fluid is directed to flow into the elongated fluid chamber via the fluid inlet, and wherein the formation fluid is separated in response to gravity as the formation fluid flows through the elongated fluid chamber;
• a water outlet formed in a bottom portion of the separator housing in a position downhole from the fluid inlet, wherein the formation water is directed to flow through the water outlet from the elongated fluid chamber;
• and
• an oil outlet formed in a top portion of the separator housing in a position downhole from the fluid inlet, wherein the production fluid is directed to flow through the oil outlet from the elongated fluid chamber;
• a lower lateral packer disposed within the lateral bore in a position downhole from the fluid separator;
• and
• a downhole pump disposed in the lateral bore, wherein the downhole pump is configured to receive the formation water from the fluid separator and pump the formation water to flow into a portion of the lateral bore downhole from the lower lateral packer.

A system comprising:

• a fluid separator disposed within a lateral bore of a multilateral well, wherein the fluid separator is configured to receive formation fluid that is produced via a lower completion assembly disposed in a main bore of the multilateral well and separate the formation fluid into formation water and production fluid, wherein the fluid separator is configured to output the production fluid to flow uphole;
• a lower lateral packer disposed within the lateral bore in a position downhole from the fluid separator;
• a downhole pump disposed in the lateral bore, wherein the downhole pump is configured to receive the formation water from the fluid separator and pump the formation water to flow into a portion of the lateral bore downhole from the lower lateral packer;
• and
• a junction tubing configured to provide a flow path for the formation fluid to flow from the main bore to the fluid separator, wherein the junction tubing includes a main tubing portion, a first tubing branch extending into the main bore, and a second tubing branch extending into the lateral bore to the fluid separator, wherein the formation fluid is directed to flow through the first tubing branch, through the main tubing portion, through the second tubing branch, and into the fluid separator.

A system comprising:

• a fluid separator disposed within a lateral bore of a multilateral well, wherein the fluid separator is configured to receive formation fluid that is produced via a lower completion assembly disposed in a main bore of the multilateral well and separate the formation fluid into formation water and production fluid, wherein the fluid separator is configured to output the production fluid to flow uphole;
• a lower lateral packer disposed within the lateral bore in a position downhole from the fluid separator;
• a downhole pump disposed in the lateral bore, wherein the downhole pump is configured to receive the formation water from the fluid separator and pump the formation water to flow into a portion of the lateral bore downhole from the lower lateral packer;
• and
• a junction tubing configured to provide a first flow path for the formation fluid to flow from the main bore to the fluid separator and a second flow path for the production fluid to flow from the fluid separator toward a surface of the multilateral well, wherein the junction tubing includes a main tubing portion, a first tubing branch extending into the main bore, and a second tubing branch extending into the lateral bore to the fluid separator, wherein the junction tubing further includes an inner tubing extending from an upper end of the main tubing portion to a lower end of the second tubing branch, wherein the first flow path extends from a lower end of the first tubing branch and through a junction annulus formed between an inner surface of the second tubing branch and an outer surface of the inner tubing to the fluid separator, and wherein the second flow path extends through the inner tubing.

A system comprising

• a fluid separator disposed within a lateral bore of a multilateral well, wherein the fluid separator is configured to receive formation fluid that is produced via a lower completion assembly disposed in a main bore of the multilateral well and separate the formation fluid into formation water and production fluid, wherein the fluid separator is configured to output the production fluid to flow uphole, and wherein the lower completion assembly is disposed within the main bore in a position downhole from a completion deflector, wherein the lower completion assembly includes:
• a lower main production tubing;
• a plurality of completion packers disposed about the lower main production tubing and configured to isolate production zones in the main bore;
• at least one screen disposed within between adjacent packers of the plurality of completion packers, wherein the at least one screen is configured to filter production fluid flowing into the lower main production tubing;
• and
• a flow control device configured to control flow of formation fluid into the lower main production tubing;
• a lower lateral packer disposed within the lateral bore in a position downhole from the fluid separator;
• and
• a downhole pump disposed in the lateral bore, wherein the downhole pump is configured to receive the formation water from the fluid separator and pump the formation water to flow into a portion of the lateral bore downhole from the lower lateral packer, wherein the completion deflector is disposed in the main bore in a position downhole from a junction between the lateral bore and the main bore, wherein the completion deflector is configured to deflect the fluid separator into the lateral bore during installation of the fluid separator, wherein the completion deflector is fluidly coupled to the lower completion assembly via a lower main production tubing, wherein the completion deflector is configured to direct formation fluid from the lower completion assembly into an annulus of the lateral bore via a central bore of the completion deflector.

A system comprising:

• a fluid separator disposed within a lateral bore of a multilateral well, wherein the fluid separator is configured to receive formation fluid that is produced via a lower completion assembly disposed in a main bore of the multilateral well and separate the formation fluid into formation water and production fluid, wherein the fluid separator is configured to output the production fluid to flow uphole, and wherein the lower completion assembly is disposed within the main bore in a position downhole from a completion deflector, wherein the lower completion assembly includes:
• a lower main production tubing;
• a plurality of completion packers disposed about the lower main production tubing and configured to isolate production zones in the main bore;
• at least one screen disposed within between adjacent packers of the plurality of completion packers, wherein the at least one screen is configured to filter production fluid flowing into the lower main production tubing;
• and
• a flow control device configured to control flow of formation fluid into the lower main production tubing;
• a lower lateral packer disposed within the lateral bore in a position downhole from the fluid separator;
• and
• a downhole pump disposed in the lateral bore, wherein the downhole pump is configured to receive the formation water from the fluid separator and pump the formation water to flow into a portion of the lateral bore downhole from the lower lateral packer, wherein the completion deflector is disposed in the main bore in a position downhole from a junction between the lateral bore and the main bore, wherein the completion deflector is configured to deflect the fluid separator into the lateral bore during installation of the fluid separator, wherein the completion deflector is fluidly coupled to the lower completion assembly via a lower main production tubing, wherein the completion deflector is configured to direct formation fluid from the lower completion assembly into a junction tubing having a main tubing portion, a first tubing branch extending into the completion deflector, and a second tubing branch extending into the lateral bore to the fluid separator.

A system comprising:

• a fluid separator disposed within a lateral bore of a multilateral well, wherein the fluid separator is configured to receive formation fluid from a main bore of the multilateral well and separate the formation fluid into formation water and production fluid, wherein the fluid separator is configured to output the production fluid into a lower annulus;
• a lower lateral packer disposed within the lateral bore in a position downhole from the fluid separator;
• an upper main bore packer disposed in the main bore in a position uphole from a junction between the main bore and the lateral bore;
• a crossflow packer disposed within the lateral bore in a position uphole from the fluid separator, wherein an upper production tubing extends from the crossflow packer and through the upper main bore packer toward a surface of the multilateral well, wherein the crossflow packer and the upper main bore packer are configured to seal an upper annulus formed uphole from the fluid separator to direct flow of formation fluid from the main bore through the upper annulus, into the crossflow packer, and toward the fluid separator via a connection tubing extending between the crossflow packer and the fluid separator, and wherein the crossflow packer and the lower lateral packer are configured to seal the lower annulus about the fluid separator to direct flow of the production fluid output from the fluid separator into the crossflow packer and to the upper production tubing;
• and
• a downhole pump disposed in the lateral bore, wherein the downhole pump is configured to receive formation water from the fluid separator via a fluid conduit extending between a water outlet of the fluid separator and a water inlet of the downhole pump, wherein the downhole pump is configured to pump the formation water into a portion of the lateral bore downhole from the lower lateral packer via a lower tubing extending from the downhole pump and into the lower lateral packer.

A method of separating oil from water downhole in a multilateral well comprising:

• directing formation fluid from a main bore of a multilateral well to flow into a lateral bore of the multilateral well, wherein the formation fluid is produced via a lower completion assembly disposed in the main bore;
• drawing the formation fluid into a fluid separator from the lateral bore, wherein the fluid separator is located in the lateral bore, and wherein the formation fluid at least includes formation water and production fluid;
• separating the production fluid from the formation water via the fluid separator;
• outputting the production fluid from the fluid separator to flow uphole toward a surface, wherein the production fluid is directed to flow uphole from the fluid separator toward the surface through a lateral annulus formed in the lateral bore and a main annulus formed in the main bore;
• and
• injecting the formation water from the fluid separator into a downhole formation disposed about the lateral bore.