Drilling cuttings would be produced when drilling. In order to recover and reuse the drilling fluids, the operator need remove the drilling cutting from the drilling fluids. The well known equipment to remove the cutting from drilling fluids is the solids control equipment. So, what is the cuttings dewatering system? And how it works to remove the cuttings in the drilling fluids?
The drilling fluids with cuttings coming from the well hole is fed to the shale shaker unit via the elevated pipeline, this the method used in oil rig package. For some other drilling project, like the no-dig horizontal directional drilling, the used drilling fluids would be collected into a pit on the ground, and then the fluids would be transferred by a slurry pump to the shale shaker unit.
Shale shaker unit is the first stage for removing the coarse size cuttings in the drilling fluids. And then the de-sander and de-silter cyclone could remove out the cuttings with size down to around 20 microns. The used drilling fluids treated by the de-silter cyclone are already clean enough to be reused. However, the cuttings with size less than 20 microns would build up to make a heavy mud which is not suitable for normal drilling application.
The dewatering system is especially equipped to remove the ultra fine solids that even cannot be separated by the decanter centrifuge unit. A decanter centrifuge like GN’s 22 inch model GNLW553 can remove the cutting with size down to 5 microns. For the even finer cuttings, we need a flocculation process to gather the ultra fine solids so that the decanter centrifuge could remove out. The polymer mixing system is a critical part of the dewatering system, GN’s polymer mixing system is designed with powder hose conveyer, automatic dosing system, mixing tank and diaphragm pump for transferring the polymer to the drilling fluids. For better flocculation process, always one acid tank and one alkali tank is equip to make the suitable PH value.
Sometimes, the drilling fluids are mixture of water and oil, GN is also able to provide the oil water separator system for recovering the water and oil.
GN now has already have the design of the complete system for drilling cutting dewatering system, for more
information, please feel free to contact with us.