# US 5,341,882 A · Well drilling cuttings disposal > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,341,882 A - Document ID: US5341882A - Status: Granted - Kind: A - Application number: 08/015,185 - Filed: 1993-02-10 - Granted: 1994-08-30 - Earliest claimed: 1993-02-10 - Assignees: Shell Oil Company - Inventors: Arthur H. Hale - Web page: https://patentgrep.com/patent/US5341882A ## CPC - E21B 41/0057: {Disposal of a fluid by injection into a subterranean formation} - C04B 18/049: {Wastes from oil or other wells, e.g. drilling mud} - C09K 8/46: containing inorganic binders, e.g. Portland cement - E21B 21/066: {with further treatment of the solids, e.g. for disposal} - E21B 33/14: for cementing casings into boreholes - Y02W 30/91: Use of waste materials as fillers for mortars or concrete - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - Y02W: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT ## Abstract Well cuttings are disposed of by solidification by combining the cuttings with water and blast furnace slag, and injection of the cuttings, water and slag into an annulus surrounding a wellbore casing and solidifying the cuttings, water and slag. Solidification in blast furnace slag cement is inexpensive, and the blast furnace slag is compatible with both oil and water based drilling muds. Drilling fluids therefore do not have to be removed from the drilling cuttings prior to solidification in the wellbore annulus. ## Claims ### Claim 1 A method for disposing of drilling cuttings comprising: decanting drilling fluids used during well drilling from cuttings attained during well drilling to concentrate said cuttings; then combining the cuttings with granulated water-quenched blast furnace slag to form a slurry; injecting the slurry into an annulus; and allowing the slurry to harden to form a solidified wellbore cement surrounding a well casing. ### Claim 2 (depends on 1) The method of claim 1 wherein said cuttings are ground to reduce the average particle size of said cuttings before the step of combining the cuttings with granulated water-quenched blast furnace slag. ### Claim 3 (depends on 1) The method of claim 1 wherein said separating step is conducted by gravity settlement. ### Claim 4 (depends on 1) The method of claim 1 wherein said separating step is conducted with a shaker table. ### Claim 5 (depends on 1) The method of claim 1 wherein a hardening activator is added to the slurry to accelerate the hardening of the slurry. ### Claim 6 (depends on 1) The method of claim 1 wherein the activator is selected from the group consisting of sodium hydroxide, calcium oxide, calcium hydroxide, magnesium hydroxide, magnesium oxide, sodium carbonate, sodium sulfate, calcium sulfate, calcium nitrate, calcium nitrite, zinc oxide, zinc carbonate, titanium carbonate, potassium hydroxide, potassium sulfate, potassium nitrate, potassium nitrite, copper sulfate, and sodium fluoride. ### Claim 7 (depends on 1) The method of claim 1 wherein at least a portion of the blast furnace slag and water had been previously circulated through a wellbore as drilling fluid. ### Claim 8 (depends on 1) The method of claim 1 wherein drilling cuttings comprise between about 14 percent and about 40 percent by weight of the slurry. ### Claim 9 (depends on 1) The method of claim 1 where in the slurry comprises between about 5 and about 40 percent by weight of blast furnace slag. ### Claim 10 (depends on 1) The method o claim 1 wherein the drilling cuttings are contaminated with between about one and about twenty percent by weight of drilling fluid. ### Claim 11 (depends on 1) The method of claim 1 wherein the drilling fluid is an oil-based drilling fluid. ### Claim 12 (depends on 1) The method of claim 1 wherein the wellbore has been drilled using a drilling slurry comprising blast furnace slag forming a blast furnace slag-containing fluid loss barrier on the outer wall of the borehole. ### Claim 13 (depends on 1) The method of claim 1 wherein the wellbore has been drilled using a drilling slurry comprising blast furnace slag forming a blast furnace slag-containing fluid loss barrier on the outer wall of the borehole. ### Claim 14 (depends on 1) The method of claim 1 wherein the water comprises a salt-containing brine. ### Claim 15 (depends on 1) The method of claim 1 wherein the water comprises sea water. ### Claim 16 A method of disposing of drilling cuttings comprising: extracting cuttings attained during well drilling from drilling fluid used during well drilling; grinding said cuttings to reduce the average particle size of said cuttings; combining drilling fluid used during well drilling, ground cuttings, and granulated water-quenched blast furnace slag to form a cementitious slurry; injecting said cementitious slurry into an annulus; allowing the cementitious slurry to harden to form a solidified wellbore cement surrounding a well casing.