New environmental regulations are more focusing on the final disposal of drilling waste cutting. Normally there are several methods for final treatment of the drilling waste management . Cuttings Re-injection is also one of the main methods. In many developed countries like USA, Canada and Germany, cuttings re-injection technology is already very mature. China drillers are now more and more adopting this technology for final treatment on drilling cuttings.
Cuttings Re-injection system is always including 3 parts as cuttings transferring, cuttings screening and Cuttings Re-injection. In the first stage for cuttings transferring, there are shale shakers, centrifuge and other traditional solids control equipment doing the same job for drilling fluids recycling. The cuttings discharged from the shale shaker will be collected by the screw conveyor and then transferred to a Venturi device to fast transferring to the storage tank. Here the centrifugal pump will be equipped for shearing the cuttings. In mud mixing system, a fine mesh screen shaker will be here for screening the cuttings suitable for re-injection to underground. The injection pump is triplex cylinder type with pressure around 40MPa. With cuttings fed by the centrifugal pump, the injection pump would pump the cuttings back to the underground via the well.
The well for re-injection could be either a new drilled one or an old well. Always a new one would be better to avoid the cuttings leak into the oil production layer. The re-injection layer could be under or above the production layer. This technology requests accurately analysis on the geological condition as not everywhere could be chosen as a point for cuttings re-injection.
Driller need choose the cuttings disposal method according to specific condition. Cuttings re-injection is a very good method for offshore drilling cuttings disposal, as it will save much time on shipping the cuttings back to onshore plant for treatment. Especially the application of SBM makes the base liquid is biodegradable for better environmental protection.
Waste Cuttings Re-injection Process for Environmental Protection is a post from: Drilling Mud Decanter Centrifuge
