Rig-up for pressure control

Abstract

A method creates and verifies a thermite-based downhole well barrier in a well. The method includes lowering a heat generating mixture to a desired location in the well; and igniting the heat generating mixture, thereby starting a heat generating process. The method further includes measuring a parameter (P(t)) representative of fluid pressure and/or fluid flow at an upper location of the well as a function of time, at least from time of ignition of the heat generating mixture. The method further includes identifying a first peak area of the measured parameter (P(t)); and determining that the integrity of the well barrier is intact by comparing the first peak area with a first peak area of an expected parameter (E(t)).

1 . A method for creating and verifying a thermite-based downhole well barrier in a well, wherein the method comprises:
 lowering a heat generating mixture to a desired location in the well;   igniting the heat generating mixture, thereby starting a heat generating process;   measuring a parameter (P(t)) representative of fluid pressure and/or fluid flow at an upper location of the well as a function of time, at least from time of ignition of the heat generating mixture;   identifying a first peak area of the measured parameter (P(t));   determining that the integrity of the well barrier is intact by comparing the first peak area with a first peak area of an expected parameter (E(t)).   
     
     
         2 . The method according to  claim 1 , wherein the method comprises determining the expected parameter (E(t)) based on:
 a generic expected parameter (GF(t)); and   specific well parameters for the well.   
     
     
         3 . The method according to  claim 1 , wherein the method comprises
 identifying a maximum point (P 1 max) within the first peak area of the measured parameter (P(t));   identifying a maximum point (E 1 max) within the first peak area of the expected parameter (E(t));   comparing the maximum point (P 1 max) within the first peak area of the measured parameter (P(t)) with the maximum point (E 1 max) within the first peak area of the expected parameter (E(t)).   
     
     
         4 . The method according to  claim 3 , wherein identifying the maximum points (P 1 max, E 1 max) comprises:
 identifying a point in time (TP 1 max) for the maximum point (P 1 max) within the first peak area of the measured parameter (P(t));   identifying a point in time (TE 1 max) for the maximum point (E 1 max) within the first peak area of the expected parameter (E(t));   comparing the point in time (TP 1 max) for the maximum point (P 1 max) within the first peak area of the measured parameter (P(t)) with the point in time (TE 1 max) for the maximum point (E 1 max) within the first peak area of the expected parameter (E(t)).   
     
     
         5 . The method according to  claim 3 , wherein identifying the maximum points (P 1 max, E 1 max) comprises:
 identifying an amplitude (AP 1 max) for the maximum point (P 1 max) within the first peak area of the measured parameter (P(t));   identifying an amplitude (AE 1 max) for the maximum point (E 1 max) within the first peak area of the expected parameter (E(t));   comparing the amplitude (AP 1 max) for the maximum point (P 1 max) within the first peak area of the measured parameter (P(t)) with the amplitude (AE 1 max) for the maximum point (E 1 max) within the first peak area of the expected parameter (E(t)).   
     
     
         6 . The method according to  claim 1 , wherein identifying the first peak area of the measured parameter (P(t)) comprises:
 identifying the first peak area of the measured parameter (P(t)) within a first time interval; and/or   identifying the first peak area of the expected parameter (E(t)) within the first time interval.   
     
     
         7 . The method according to  claim 6 , wherein the first time interval is 1-240 seconds measured from the time of ignition. 
     
     
         8 . The method according to  claim 1 , wherein the method comprises:
 identifying in initial maximum point (P 0 max) of the measured parameter (P(t)), wherein a point in time (TP 0 max) of the initial maximum point (P 0 max) is occurring prior to the point in time (TP 1 max) of the maximum point (PV 1 max) and wherein an amplitude (AP 0 max) of the initial maximum point (P 0 max) is lower than the amplitude (AP 1 max) of the maximum point (PV 1 max);   identifying an initial maximum point (E 0 max) of the expected parameter (E(t)), wherein a point in time (TE 0 max) of the initial maximum point (E 0 max) is occurring prior to the point in time (TE 1 max) of the maximum point (PE 1 max) and wherein an amplitude (AE 0 max) of the initial maximum point (E 0 max) is lower than the amplitude (AE 1 max) of the maximum point (PE 1 max);   comparing the amplitude (AP 0 max) and/or the point in time (TP 0 max) of the initial maximum point (P 0 max) of the measured parameter (P(t)) with the amplitude (AE 0 max) and/or the point in time (TP 0 max) for the maximum point (E 0 max) of the expected parameter (E(t)).   
     
     
         9 . The method according to  claim 1 , wherein the method comprises:
 identifying a second peak area of the measured parameter (P(t));   determining that the integrity of the well barrier is intact by comparing the second peak area with a second area of the expected parameter (E(t)).   
     
     
         10 . The method according to  claim 9 , wherein the method comprises:
 identifying a maximum point (P 2 max) within the second peak area of the measured parameter (P(t)) as a point of time (TP 2 max) or an amplitude (AP 2 max);   comparing the point of time (TP 2 max) or the amplitude (AP 2 max) for the maximum point (P 2 max) with a time (TE 2 max) or an amplitude (AE 2 max) for a maximum point (E 2 max) of the second area of the expected parameter (E(t)).   
     
     
         11 . The method according to  claim 9 , wherein identifying the second peak area of the measured parameter (P(t)) comprises:
 identifying the second peak area of the measured parameter (P(t)) within a second time interval; and/or   identifying the second peak area of the expected parameter (E(t)) within the second time interval.   
     
     
         12 . The method according to  claim 11 , wherein the second time interval is 0.5-4 hours measured from the time of ignition. 
     
     
         13 . The method according to  claim 1 , wherein the method comprises:
 connecting a pressure-sealed tank to a fluid outlet of the well;   receiving well fluid from the well into the pressure-sealed tank as a result of the heat generating process;   measuring the parameter (P(t)) inside the pressure-sealed tank.   
     
     
         14 . The method according to  claim 13 , wherein the method comprises:
 increasing the pressure inside the pressure-sealed tank to a predetermined pressure above the topside ambient pressure before the time of ignition.   
     
     
         15 . The method according to  claim 14 , wherein the method comprises:
 measuring a pressure reduction in the pressure-sealed tank resulting from a fluid leakage in a period of time prior to the time of ignition;   adjusting the parameter (P(t)) and/or the expected parameter (E(t)) according to the measured pressure reduction.   
     
     
         16 . A system for creating and verifying a thermite-based downhole well barrier in a well, wherein the system comprises:
 a heat generating mixture located at a desired location in the well;   an ignition device for igniting the heat generating mixture at the desired location in the well;   a measuring device arranged at an upper location of the well, the measuring device being configured for measuring a parameter (P(t)) representative of pressure (Δp(t)) and/or fluid flow (ΔV(t)) as function of time, at least from time of ignition of the heat generating mixture;   a user interface connected to the measurement device for providing an output of the measurements of the parameter (P(t)) to a user;   wherein the user interface comprises a signal processing unit configured to:
 identify a first peak area of the measured parameter (P(t)); 
 compare the first peak area with an expected first peak area; 
 wherein it can be determined that the integrity of the well barrier is intact based on the comparison of the first peak area with the expected first peak area. 
   
     
     
         17 . The system according to  claim 16 , wherein the signal processing unit is determining that the integrity of the well barrier is intact based on the comparison of the first peak area with the expected first peak area. 
     
     
         18 . The system according to  claim 16 , wherein the user interface comprises a display configured to display:
 the measured parameter (P(t));   the expected parameter (E(t)).   
     
     
         19 . The system according to  claim 16 , wherein the system comprises a pressure-sealed tank for receiving the well fluid from the well, the pressure-sealed tank being fluidly connected to a fluid outlet of the well. 
     
     
         20 . The system according to  claim 19 , wherein the measuring device is located within the pressure-sealed tank. 
     
     
         21 . The system according to  claim 16 , wherein the system comprises a fluid line connected at one end to a fluid outlet of the well, and at its other end to an inlet of the pressure-sealed tank. 
     
     
         22 . (canceled) 
     
     
         23 . The method according to  claim 1 , wherein the first peak area of the measured parameter (P(t)) is a result of gas produced in the initial phase of the heat generating process.