Well treating process using sacrificial plug

Claim 2

A process for treating an earth formation interval in a penetrating wellbore comprising: isolating that portion of the wellbore which lies adjacent the formation interval to be treated; providing a conduit between the surface of said wellbore and said portion of said wellbore; injecting a first well treating fluid into said formation interval through said conduit; injecting a second well treating fluid of a different composition from said first treating fluid into said formation interval through said conduit immediately behind said one well treating fluid; and separating said first and said second well treating fluids while they are in said conduit with a sacrificial plug comprised of material which will substantially maintain its integrity while in said conduit but will decompose once said sacrificial plug reaches said portion of said wellbore.

Claim 3

The process of claim 1 wherein: said sacrificial plug material is a solid material which will melt at the temperature existing in said portion of said wellbore.

Claim 4

The process of claim 2 wherein: said sacrificial plug material is comprised of solid, eutectic combination of organic compounds which will melt at the temperature existing in said portion of said wellbore.

Claim 5

The process of claim 3 wherein: said eutectic combination of organic compounds comprises napthalene and an organic additive which adjusts the temperature at which said eutectic combination will melt.

Claim 6

The process of claim 2 wherein: said sacrificial plug material is comprised of a wax material which will melt at the temperature existing in said portion of said wellbore.

Claim 7

The process of claim 1 wherein: said sacrificial plug material is a solid material which will dissolve in well fluid which is present in said portion of said wellbore.

Claim 8

A process for treating a plurality of earth formation intervals penetrated by a wellbore, said process comprising: positioning a lower packer means adjacent the lower point of the first of said formation intervals to be treated and setting said lower packer means to close said wellbore at said lower point; positioning an upper packer means adjacent the upper point of said first of said formation intervals to be treated and setting said upper packer means to close said wellbore at said upper point and to isolate a first portion of said wellbore between said packer meaNs which lies adjacent said first of said formation intervals to be treated; providing a conduit which extends from the surface of said wellbore, through said upper packer means, and into said first portion of said wellbore; injecting one well treating fluid into said first formation interval through said conduit; injecting another well treating fluid into said first formation interval through said conduit immediately behind said one well treating fluid; separating said one and said another well treating fluid while they are in said conduit with a sacrificial plug comprised of material which will substantially maintain its integrity while in said conduit but will decompose when said sacrificial plug reaches said first portion of said wellbore; releasing said upper and said lower packer means; repositioning said lower packer means adjacent the lower point of the second of said formation intervals to be treated and setting said lower packer means to close said wellbore at said point; repositioning said upper packer means adjacent the upper point of said second formation interval to be treated and setting said upper packer to close said wellbore at said upper point and to isolate a second portion of said wellbore between said packer means which lies adjacent said second of said formation intervals to be treated; providing said conduit from the surface of said wellbore, through said upper packer means, and into said second portion of said wellbore, the steps of releasing, repositioning, and resetting said packer means and of providing said conduit being carried out without removing a substantial portion of said conduit from said wellbore; injecting one well treating fluid into said second formation through said conduit; injecting another well treating fluid into said second formation interval through said conduit immediately behind said one well treating fluid; and separating said one and said another well treating fluids while they are in said conduit with another sacrificial plug comprised of material which will substantially maintain its integrity while in said conduit but will decompose when said another sacrificial plug reaches said second portion of said wellbore.

Claim 9

A process for treating a plurality of earth formation intervals penetrated by a wellbore, said process comprising: positioning a lower packer means adjacent the lower point of the first of said formation intervals to be treated and setting said lower packer means to close said wellbore at said lower point; positioning an upper packer means adjacent the upper point of said first of said formation intervals to be treated and setting said upper packer means to close said wellbore at said upper point and to isolate a first portion of said wellbore between said packer meaNs which lies adjacent said first of said formation intervals to be treated; providing a conduit which extends from the surface of said wellbore, through said upper packer means, and into said first portion of said wellbore; injecting one well treating fluid into said first formation interval through said conduit; injecting another well treating fluid into said first formation interval through said conduit immediately behind said one well treating fluid; separating said one and said another well treating fluid while they are in said conduit with a sacrificial plug comprised of material which will substantially maintain its integrity while in said conduit but will decompose when said sacrificial plug reaches said first portion of said wellbore; releasing said upper and said lower packer means; repositioning said lower packer means adjacent the lower point of the second of said formation intervals to be treated and setting said lower packer means to close said wellbore at said point; repositioning said upper packer means adjacent the upper point of said second formation interval to be treated and setting said upper packer to close said wellbore at said upper point and to isolate a second portion of said wellbore between said packer means which lies adjacent said second of said formation intervals to be treated; providing said conduit from the surface of said wellbore, through said upper packer means, and into said second portion of said wellbore, the steps of releasing, repositioning, and resetting said packer means and of providing said conduit being carried out without removing a substantial portion of said conduit from said wellbore; injecting one well treating fluid into said second formation through said conduit; injecting another well treating fluid into said second formation interval through said conduit immediately behind said one well treating fluid; and separating said one and said another well treating fluids while they are in said conduit with another sacrificial plug comprised of material which will substantially maintain its integrity while in said conduit but will decompose when said another sacrificial plug reaches said second portion of said wellbore.

Claim 10

The process of claim 7 further comprising: repeating the above steps until all of said formation intervals have been treated.

Claim 11

The process of claim 7 wherein: said sacrificial plug material used in said first portion is solid material which will melt at the temperature existing in said first portion of said wellbore; and said sacrificial plug material used in said second portion is a solid material which will melt at the temperature existing in said second portion of said wellbore.

Claim 12

The process of claim 9 wherein: said sacrificial plug material used in said first portion is comprised of a wax material which will melt at the temperature existing in said first portion of said wellbore; and said sacrificial plug material used in said second portion is comprised of a wax material which will melt at the temperature existing in said second portion of said wellbore.

Claim 13

The process of claim 9 wherein: said sacrificial plug material used in said first portion is comprised of a solid, eutectic combination of organic compounds which will melt at the temperature existing in said first portion of said wellbore; and said sacrificial plug material used in said second portion is comprised of solid, eutectic combination of organic compounds which will melt at the temperature existing in said second portion of said wellbore.

Claim 14

The process of claim 10 wherein: said eutectic combination of organic compounds comprises napthalene and an organic additive which adjusts the temperature at which said eutectic combination will melt.

Claim 15

The process of claim 7 wherein: said sacrificial plug material used in said first portion is a solid material which will dissolve in well fluid which is present in said firSt portion of said wellbore; and said sacrificial plug material used in said second portion is a solid material which will dissolve in well fluid which is present in said second portion of said wellbore.