Method and Apparatus for Processing Fluid from a Well

Abstract

An assembly is for an oil and gas production platform or rig and related methods. The platform or rig may have a Christmas tree deck and a hatch deck above the Christmas tree deck. The assembly may have a Christmas tree connected to a top of a wellhead on the platform or rig located at the Christmas tree deck. The assembly may further have a processing unit comprising at least one separator, positioned above and connected onto a top of the Christmas tree. The Christmas tree may bear at least partially the weight of said separator. The separator may be operable for receiving production fluid from at least one oil and gas production well and removing solids to clean the production fluid.

1 . An assembly for an oil and gas production platform or rig, the platform or rig having a Christmas tree deck and a hatch deck above the Christmas tree deck, the assembly comprising:
 a Christmas tree connected to a top of a wellhead on the platform or rig, the Christmas tree located at the Christmas tree deck; and   a processing unit comprising at least one separator, positioned above and connected onto a top of the Christmas tree, the Christmas tree bearing at least partially the weight of said separator;   wherein the separator is operable for receiving production fluid from at least one oil and gas production well and removing solids to clean the production fluid.   
     
     
         2 . An assembly comprising:
 a Christmas tree connected to a top of a wellhead, the Christmas tree having a vertical bore for accessing the well by an intervention or another tool lowered on a wireline or tubing from above the vertical bore through said tree; and   a processing unit comprising at least one separator, positioned above and connected onto a top of the Christmas tree, the Christmas tree bearing at least partially the weight of said separator;   wherein the processing unit is further arranged to provide full diameter access to the vertical bore of the Christmas tree; and   wherein the separator is operable for receiving oil and gas production fluid from at least one well and removing solids to clean the production fluid.   
     
     
         3 . The assembly as claimed in  claim 2  on an oil and gas production platform or rig, said platform or rig having a Christmas tree deck and a hatch deck above the Christmas tree deck, wherein the Christmas tree is arranged at the Christmas tree deck. 
     
     
         4 . The assembly as claimed in  claim 1 , wherein the separator comprises a de-sander. 
     
     
         5 . The assembly as claimed in  claim 1 , wherein the separator comprises a de-sander having a processing tank mounted in the processing unit. 
     
     
         6 . The assembly as claimed in  claim 5 , wherein the de-sander has an associated solids container comprising a processing tank for containing removed solids transferred from the de-sander in order to be later disposed of. 
     
     
         7 . The assembly as claimed in  claim 1 , wherein the processing unit comprises first and second de-sanders operable in parallel to clean the production fluid. 
     
     
         8 . The assembly as claimed in  claim 1 , wherein the processing unit includes a degasser comprising a processing tank, for removing gas from the production fluid upstream from a de-sander. 
     
     
         9 . The assembly as claimed in  claim 1 , wherein the processing unit has a vertical conduit or passageway aligned with the vertical bore of Christmas tree for deploying an intervention or other tool on a wireline or tubing into the valve tree. 
     
     
         10 . The assembly as claimed in  claim 9 , wherein the processing unit comprises a vertical conduit aligned with a vertical bore of the Christmas tree, and the separator is a de-sander, wherein the de-sander and a solids container associated with the de-sander are spaced apart in the processing unit along the conduit or passageway. 
     
     
         11 . The assembly as claimed in  claim 9 , wherein the processing unit comprises a vertical conduit or passageway aligned with a vertical bore of the Christmas tree, and the separator comprises a processing tank which extends longitudinally along the vertical conduit or passageway. 
     
     
         12 . The assembly as claimed in  claim 9 , wherein the conduit or passageway comprises a vertical pipe section. 
     
     
         13 . The assembly as claimed in  claim 9 , wherein the processing unit comprises a connector for connecting the processing unit onto the top of the Christmas tree. 
     
     
         14 . The assembly as claimed in  claim 13 , wherein the connector is configured to mate with a top flange of an upper bore portion of the vertical bore of the Christmas tree. 
     
     
         15 . The assembly as claimed in  claim 9 , wherein the processing unit comprises a mount for mounting the separator therein. 
     
     
         16 . The assembly as claimed in  claim 9 , wherein the processing unit further comprises either or both of an emergency shut down valve and a choke. 
     
     
         17 . A method of equipping a Christmas tree for processing fluid from at least one oil and gas production well using an assembly for an oil and gas production platform or rig, the platform or rig having a Christmas tree deck and a hatch deck above the Christmas tree deck, the assembly comprising:
 a Christmas tree connected to a top of a wellhead on the platform or rig, the Christmas tree located at the Christmas tree deck; and   a processing unit comprising at least one separator, positioned above and connected onto a top of the Christmas tree, the Christmas tree bearing at least partially the weight of said separator;   wherein the separator is operable for receiving production fluid from at least one oil and gas production well and removing solids to clean the production fluid, wherein the processing unit has a vertical conduit or passageway aligned with the vertical bore of Christmas tree for deploying an intervention or other tool on a wireline or tubing into the valve tree;   the method comprising: applying the processing unit to the Christmas tree such that the separator is at least partially supported on top of the Christmas tree whereby said Christmas tree bears at least part of the weight of the separator.   
     
     
         18 . The method as claimed in  claim 17 , which is performed to equip the Christmas tree on an oil and gas production platform or rig, said platform or rig having a Christmas tree deck and a hatch deck above the Christmas tree deck, wherein the Christmas tree is arranged at the Christmas tree deck, the method including the step of lowering the apparatus through a hatch in the hatch deck onto the Christmas tree, so as to locate the separator in place, at least partially supported on the top of the Christmas tree. 
     
     
         19 . A method of performing an intervention operation through the vertical bore of the Christmas tree of an assembly for an oil and gas production platform or rig, the platform or rig having a Christmas tree deck and a hatch deck above the Christmas tree deck, the assembly comprising:
 a Christmas tree connected to a top of a wellhead on the platform or rig, the Christmas tree located at the Christmas tree deck; and   a processing unit comprising at least one separator, positioned above and connected onto a top of the Christmas tree, the Christmas tree bearing at least partially the weight of said separator;   wherein the separator is operable for receiving production fluid from at least one oil and gas production well and removing solids to clean the production fluid;   the method comprising:   lowering intervention equipment through the vertical bore, while the separator remains in place and is at least partially supported on the top of the Christmas tree.