Assisted autonomous treatment system and process in pre-salt production platforms, and their uses

Abstract

The present invention relates to a system and process for assisted autonomous treatment for removing and/or inhibiting scale with desulfated seawater on pre-salt production platforms, using production facilities and injection water, without the need of using a stimulation vessel or a workover rig.

1 . An autonomous treatment process on pre-salt production platforms comprising:
 identifying signs of scaling in a producing well;   conducting a first test of a production of the well to determine a pre-treatment reference condition;   shutting down the producing well;   executing a scale removal and inhibition procedure comprising:
 pumping a treatment volume of desulphated water ranging from 500 bbl to 4500 bbl; 
 injecting a chemical sequence into the treatment volume; 
 aligning a production and an injection train; 
 maintaining a log of pressure gauges of a production well system within a range of 80 to 220 kgf/cm 2  and a flow rate range of diesel injection and of a treatment solution injection within a range from 2 bpm to 30 bpm; and 
   restarting the production well;   collecting samples from the production well;   conducting a second test of the production of the well to determine an efficiency of the treatment.   
     
     
         2 . The autonomous treatment process of  claim 1 , wherein identifying signs of scaling comprises one or more of:
 monitoring variations in in a pressure differential between a string PDG (permanent downhole gauge) and an annulus PDG ranging from 4 to 10 kgf/cm 2 ;   monitoring a temperature variation in the string PDG ranging from −2° C. to 2° C.; and   monitoring a drop of greater than 5% of a well potential.   
     
     
         3 . The autonomous treatment process of  claim 1 , wherein conducting the first and second test of the production well comprises a measuring flow rate data and a production profile. 
     
     
         4 . The autonomous treatment process of  claim 3 , wherein the second test is conducted shortly after executing the scale removal and inhibition procedure. 
     
     
         5 . The autonomous treatment process of  claim 1 , further comprising aligning a production and an injection train with at least a second alignment valve of an assisted autonomous treatment system at least by:
 closing a first shut down valve of a water and gas (WAG) portion of the assisted autonomous treatment system,   opening a first choke valve the WAG portion,   opening a second alignment valve of a producing portion of the assisted autonomous treatment system, and   activating the water pump to pump desulphated water through the first choke valve and into a WAG injection well line, into a first PIG receiver header and a test header, into a second PIG receiver by-pass, into a producing well line, and into a producing well.   
     
     
         6 . The autonomous treatment process of  claim 5 , further comprising sending desulphated water from a desulphated water source to a WAG injection well when the first shut down valve is open and the water pump is activated to pump the desulphated water into the WAG injection well. 
     
     
         7 . The autonomous treatment process of  claim 5 , further comprising aligning to test the producing well at least by opening the second alignment valve to open a flow path to a second PIG receiver header and the second PIG receiver by-pass. 
     
     
         8 . The autonomous treatment process of  claim 5 , further comprising:
 aligning a production and an injection train with at least the second alignment valve of the producing portion, wherein aligning a production and an injection train further comprises:
 opening the second shut down valve, 
 closing the second alignment valve, and 
 activating a diesel fuel pump is activated to pump diesel from a diesel tank into the producing well line. 
   
     
     
         9 . The autonomous treatment process of  claim 5 , wherein injecting a chemical sequence into the treatment volume comprises injecting a scale inhibitor into the producing well line via a triplex chemical injection pump. 
     
     
         10 . An assisted autonomous treatment system on pre-salt production platforms, comprising:
 one or more controllers configured to:
 identify signs of scaling in a producing well; 
 conduct a first test of a production of the well to determine a pre-treatment reference condition; 
 shut down the producing well, 
 execute a scale removal and inhibition procedure comprising:
 pumping a treatment volume of desulphated water ranging from 500 bbl to 4500 bbl with a water injection pump of a WAG (water and gas) portion of the assisted autonomous treatment system, the water injection pump fluidly coupled to a desulphated water source, the WAG portion comprising a WAG injection well in fluid communication with a WAG injection well line, the WAG injection well line comprising a first shut down valve and a first alignment valve; 
 inject a chemical sequence into the treatment volume with a triplex injection pump of a producing portion of the assisted autonomous treatment system, the triplex chemical injection pump in fluid communication with a producing line of the producing portion between a producing well and a second alignment valve of the producing system, the triplex chemical injection pump positioned downstream of a diesel tank, the producing well in fluid communication with the producing line, the producing line comprising the second alignment valve of the producing system, align a production and an injection train with at least the second alignment valve of the producing portion; 
 maintain a log of pressure gauges of the production well system within a range of 80 to 220 kgf/cm 2  and a flow rate range of diesel injection and of a treatment solution injection within a range from 2 bpm to 30 bpm; 
 restart the production well; 
 collect samples from the production well; 
 conduct a second test of the production of the well to determine an efficiency of the treatment. 
 
   
     
     
         11 . The assisted autonomous treatment system of  claim 10 , wherein the WAG portion comprises:
 the WAG injection well in fluid communication with the WAG injection well line, the WAG injection well line comprising the first shut down valve and the first alignment valve;   the water injection pump fluidly coupled to a desulfated water source,   a first choke valve positioned downstream of the water injection pump, wherein the first choke valve is in fluid communication with the WAG injection well line between the first shut down valve and the first alignment valve;   a first PIG receiver header in fluid communication with the first alignment valve;   a first PIG receiver by-pass in fluid communication with the first PIG receiver header; and   a test header in fluid communication with the first PIG receiver by-pass.   
     
     
         12 . The assisted autonomous treatment system of  claim 11 , wherein the producing portion comprises:
 the producing well in fluid communication with the producing line, the producing line comprising the second alignment valve;   the triplex chemical injection pump in fluid communication with the producing line between the producing well and the second alignment valve, the triplex chemical injection pump positioned downstream of a diesel tank;   a second PIG receiver header in fluid communication with the second alignment valve; and   a second PIG receiver by-pass in fluid communication with the second PIG receiver header and the test header.   
     
     
         13 . The assisted autonomous treatment system of  claim 12 , wherein to align a production and an injection train with at least the second alignment valve of the producing portion, the one or more controllers are further configured to close the first shut down valve, open the first choke valve, open the second alignment valve, and activate the water pump to pump desulphated water through the first choke valve and into the WAG injection well line, into the first PIG receiver header and the test header, into the second PIG receiver by-pass, into the producing well line, and into the producing well. 
     
     
         14 . The assisted autonomous treatment system of  claim 13 , wherein the first choke valve is configured to adjust the flow rate of desulphated seawater injected into the producing well. 
     
     
         15 . The assisted autonomous treatment system of  claim 13 , wherein the one or more controllers are further configured to send desulphated water from the desulphated water source to the WAG injection well when the first shut down valve is open and the water pump is activated to pump the desulphated water into the WAG injection well. 
     
     
         16 . The assisted autonomous treatment system of  claim 13 , wherein the one or more controllers are further configured to align to test the producing well at least by opening the second alignment valve to open a flow path to the second PIG receiver header and the second PIG receiver by-pass. 
     
     
         17 . The assisted autonomous treatment system of  claim 16 , wherein to align a production and an injection train with at least the second alignment valve of the producing portion, the one or more controllers are further configured to align for injection of diesel fuel into the producing well at least by opening the second shut down valve, closing the second alignment valve, and activating a diesel fuel pump is activated to pump diesel from the diesel tank into the producing well line. 
     
     
         18 . The assisted autonomous treatment system of  claim 10 , wherein the desulphated water is produced by a stationary production unit (SPU) and eliminates a need for a preparation tank for the fluid to be injected. 
     
     
         19 . The assisted autonomous treatment system of  claim 18 , wherein the SPU is a controller of log parameters, control, and safety. 
     
     
         20 . The assisted autonomous treatment system of  claim 10 , wherein to inject a chemical sequence into the treatment volume with a triplex injection pump, the one or more controllers are further configured to inject a scale inhibitor into the producing well line via the triplex chemical injection pump.