Multi-function testing apparatus for cement and methods of using the same

A method of testing the healing capacity of a self-healing cement comprising:

• (a) curing a self-healing cement in a test cell, the test cell having an inlet port and an outlet port;
• (b) inducing a fracture of pre-determined width in the cured self-healing cement while the cured self-healing cement is within the test cell by flowing a formation fluid under pressure into the test cell;
• (c) waiting for a time sufficient for the self-healing cement to seal the induced fracture;
• and
• (d) inducing a fracture of pre-determined width in the sealed self-healing cement of step (c) and measuring the hydraulic pressure required to induce the fracture while the self-healing cement is within the test cell.

A method of testing the healing capacity of a self-healing cement in a testing apparatus, the testing apparatus comprising a test cell, an inlet port, an outlet port diametrically opposite to the inlet port, a bottom port, a piston and an adjustable piston depth-setting rod, wherein the adjustable piston depth-setting rod is adjacent to the piston, the method comprising:

• (a) introducing into the test cell through the bottom port a cement slurry wherein the piston is closest to the inlet port of the cement slurry to the test cell;
• (b) curing the self-healing cement in the test cell, wherein the location of the bottommost portion of the piston during curing is substantially the same as the vertical axis of the inlet port and outlet port;
• (c) defining a travel path for the piston by moving the adjustable piston depth-setting rod a set distance away from the piston;
• (d) inducing a fracture in the cured cement by flowing a formation fluid under pressure into the test cell through the inlet port, the fracture having a width defined by the travel path;
• (e) waiting for a time sufficient for the self-healing cement to seal the induced fracture;
• and
• (f) inducing a fracture of defined fracture width in the sealed self-healing cement of step (e) and measuring the hydraulic pressure required to induce the fracture.

A method of measuring the resistance of a set cement to carbon dioxide channeling in a testing apparatus, the testing apparatus comprising a test cell, a inlet port, a outlet port diametrically opposite to the inlet port and a bottom port, wherein the method comprises:

• (a) introducing into the test cell through the bottom port a cement slurry;
• (b) curing the self-healing cement in the test cell;
• (c) injecting carbonic acid into the test cell through the inlet port;
• and
• (d) measuring the flow of water exiting the outlet port.

A method of testing the hydraulic bonding strength of a set cement in a testing apparatus, the testing apparatus comprising a test cell, a inlet port, a outlet port diametrically opposite to the inlet port, a bottom port, a piston and an adjustable piston depth-setting rod, wherein the adjustable piston depth-setting rod is adjacent to the piston, the method comprising:

• (a) closing the inlet port and outlet port and introducing into the test cell through the bottom of test cell port a cement slurry wherein the piston is closest to the bottom port;
• (b) curing the cement in the test cell, wherein the location of the bottommost portion of the piston during curing lies substantially along the horizontal axis defined by the inlet port and the outlet port and the uppermost portion of the test cell;
• (c) opening the inlet port and outlet port and defining a travel path for the piston by moving the adjustable piston depth-setting rod a set distance away from the piston;
• (d) introducing a formation fluid into the test cell through the inlet port and monitoring the travel distance of the piston, wherein the formation fluid is introduced into the test cell under a defined flow rate and defined pressure;
• (e) monitoring the movement of the piston until the cement bond is broken;
• and
• (f) determining the hydraulic bonding strength of the cement from the pressure required to break the bonding indicated by the travel distance of the piston.