Monitoring diversion degradation in a well

Abstract

A degradable diverter is placed in a flow path to divert fluid flow and exposed to degradation conditions, and after sensing a response to a pressure wave to determine the diverter has degraded, placing the well in service. Also, a treatment sequence is initiated according to a treatment schedule, a degradable diverter is placed in a flow path to divert treatment fluid, and, before completing the treatment, an interruption of the treatment schedule is followed by sensing a response to a pressure wave generated in the well to determine the status of the degradable diverter. Also, in a series of stages a degradable diverter is placed in a flow path, a response to a pressure wave is sensed to confirm placement, fluid flow is diverted, and the sequence repeated for subsequent stages.

What is claimed is: 
     
         1 . A method for treating a well, comprising:
 (a) placing a degradable diverter in a flow path of the well to divert treatment fluid flow from the flow path;   (b) exposing the degradable diverter to degradation conditions;   (c) sensing a response to a pressure wave generated in the well to determine whether the degradable diverter has substantially degraded; and   (d) after determining that the degradable diverter has substantially degraded, performing an operation and flowing fluid through the flow path.   
     
     
         2 . The method of  claim 1 , wherein the degradable diverter comprises a mechanical diverter. 
     
     
         3 . The method of  claim 1 , wherein the degradable diverter comprises a chemical diversion material. 
     
     
         4 . The method of  claim 1 , wherein the flow path comprises a perforation or fracture in communication with the well. 
     
     
         5 . The method of  claim 1 , wherein the flow path comprises a first portion of the wellbore isolated from a second portion of the wellbore by the diverter. 
     
     
         6 . The method of  claim 1 , further comprising continuously or periodically generating the pressure wave and sensing the response to monitor the placement of the diverter, degradation of the diverter, or a combination thereof. 
     
     
         7 . The method of  claim 6 , wherein the placement or degradation of the diverter or both are monitored by changes in the sensed response. 
     
     
         8 . The method of  claim 6 , wherein the pressure wave is generated at a frequency from 1 per second to 1 per minute. 
     
     
         9 . The method of  claim 6 , wherein the pressure wave generation comprises a sweep circuit comprising a regularly changing frequency. 
     
     
         10 . The method of  claim 9 , wherein the pressure wave has overlapping intervals, and further comprising deconvoluting the sensed response. 
     
     
         11 . The method of  claim 6 , further comprising automatically sending data derived from the sensed response to a remote receiver. 
     
     
         12 . The method of  claim 1 , wherein the pressure wave is generated by a fluid hammer. 
     
     
         13 . The method of  claim 1 , wherein the pressure wave is generated by a pressure signal emitter device in communication with the well. 
     
     
         14 . The method of  claim 1 , wherein the flowing of the fluid in (d) comprises producing reservoir fluid. 
     
     
         15 . The method of  claim 1 , wherein the flowing of the fluid in (d) comprises fluid injection into a subterranean formation. 
     
     
         16 . A method for treating a well, comprising:
 (a) initiating a treatment sequence according to a planned treatment schedule comprising introducing treatment fluid into the well in a plurality of stages;   (b) placing a degradable diverter in a flow path of the well to divert treatment fluid from the flow path;   (c) interrupting the treatment schedule comprising shutting in the well;   (d) sensing a response to a pressure wave generated in the well to determine whether the degradable diverter has degraded; and   (e) after determining that the degradable diverter has not degraded, performing an operation or resuming the treatment sequence.   
     
     
         17 . The method of  claim 16 , wherein the resumption of the treatment sequence is according to the planned treatment schedule. 
     
     
         18 . The method of  claim 16 , wherein the resumption of the treatment sequence is according to a new treatment schedule revised in response to the interruption. 
     
     
         19 . The method of  claim 16 , further comprising exposing the diverter to degradation conditions; sensing a response to a pressure wave generated in the well to determine whether the degradable diverter has degraded; and after determining that the degradable diverter has degraded, flowing fluid through the flow path. 
     
     
         20 . A method for treating a well, comprising:
 (a) placing a degradable diverter in a flow path of the well;   (b) sensing a response to a pressure wave generated in the well to confirm the placement of the degradable diverter;   (c) diverting fluid flow from the flow path;   (d) exposing the diverter to degradation conditions;   (e) sensing a response to a pressure wave generated in the well to determine whether the degradable diverter has degraded; and   (f) after determining that the degradable diverter has degraded, performing an operation and flowing fluid through the flow path.   
     
     
         21 . A method for treating a well, comprising:
 (a) placing a degradable diverter in a flow path of the well;   (b) sensing a response to a pressure wave generated in the well to confirm the placement of the degradable diverter;   (c) diverting fluid flow from the flow path;   (d) repeating (a)-(c) one or more times for a plurality of respective degradable diverters placed in respective flow paths;   (e) exposing the diverters to degradation conditions;   (f) sensing a response to a pressure wave generated in the well to determine whether the degradable diverters have degraded; and   (g) after determining that the degradable diverters have degraded, placing the well in service and flowing fluid through the flow paths.