Abstract: A hermetically sealed horizontal washing decanter centrifuge for enhanced drilling fluid recovery and drilled solids washing. A process and apparatus for liquid phase-solid phase separation of oil based drilling mud-containing drill cuttings is described including flowing the drilling mud-containing drill cuttings into a horizontal washing decanter wherein the stresses imposed within the decanter act as a wash as the diluent and oil based drilling mud move away from the drill cuttings. Diluent is added prior to flowing the drilling mud containing drill cutting to the hermetically sealed horizontal washing decanter centrifuge. The entire process is performed in a gas-tight environment preventing escape of diluent from the process into the external atmosphere and preventing introduction of gases into the process from the external atmosphere.

Abstract: A process for removing hydrocarbons and water from hydrocarbon and/or water containing drilling waste. The process includes introducing hydrocarbon contaminated drill cuttings and a cleaning solvent into a solvent wash tank. Prior to introducing the hydrocarbon contaminated drill cuttings into a solvent wash tank, the hydrocarbon contaminated drill cuttings are treated with a hydrocarbon solvent such as hexane to break the surface tension of the hydrocarbons in a solvent sealed vertical centrifugal separator to remove hydrocarbons from the hydrocarbon contaminated drill cuttings, resulting in improved efficiency of the hydrocarbon removal process. Apparatus for performing the process is also described.

Abstract: A hermetically sealed horizontal washing decanter centrifuge for enhanced drilling fluid recovery and drilled solids washing. A process and apparatus for liquid phase-solid phase separation of oil based drilling mud-containing drill cuttings is described including flowing the drilling mud-containing drill cuttings into a horizontal washing decanter wherein the stresses imposed within the decanter act as a wash as the diluent and oil based drilling mud move away from the drill cuttings. Diluent is added prior to flowing the drilling mud containing drill cutting to the hermetically sealed horizontal washing decanter centrifuge. The entire process is performed in a gas-tight environment preventing escape of diluent from the process into the external atmosphere and preventing introduction of gases into the process from the external atmosphere.

Abstract: A process for removing hydrocarbons and water from hydrocarbon and/or water containing drilling waste. The process includes introducing hydrocarbon contaminated drill cuttings and a cleaning solvent into a solvent wash tank. Prior to introducing the hydrocarbon contaminated drill cuttings into a solvent wash tank, the hydrocarbon contaminated drill cuttings are treated with a hydrocarbon solvent such as hexane to break the surface tension of the hydrocarbons in a solvent sealed vertical centrifugal separator to remove hydrocarbons from the hydrocarbon contaminated drill cuttings, resulting in improved efficiency of the hydrocarbon removal process. Apparatus for performing the process is also described.