Treatment techniques for drill fluids, cuttings and other oil field wastes

Claim 1

Process for treatment of oilfield wastes for disposal or recovery, the oilfield wastes including one or more types of drilling mud, drill cuttings and soil solids, petroleum, diesel and other oils, salts, and water, comprising separating the liquid components of said oilfield wastes from the solid components thereof by filtration to produce a filtrate, treating said filtrate with acid to reduce its pH and with a flocculating agent to flocculate solids therefrom and filtering said flocculated solids from the remaining liquid and combining same with said solid components, heating and incinerating said solid components at a temperature between about 200° F. (93° K.) and about 1500° F. (816° K.) with hot gases to produce char solids and flue gas containing materials vaporized from said solid components, cooling said char solids to a temperature between about 190° F. (88° K.) and about 350° F. (177° K.) by heat exchange with air to produce heated combustion air, cooling said flue gas to a temperature between about 200° F. (93° K.) and about 700° F. (371° K.) by heat exchange with air to produce condensed materials and additional heated combustion air, burning a fuel with said heated combustion air and said additional heated combustion air to produce said hot gases, and recovering said cooled char solids and said condensed materials for disposal or use.