Drilling waste cuttings treatment of Pit Less Mud Systems are also known as closed loop systems. In this closed loop systems solid control equipment are used to minimize the wastage of natural oils used in drilling. The solid control equipment that are used in pit less mud system are:
1) Shale Shaker :
This is the first equipment in solid control equipment for drilling waste cutting. It consists of s screen that does the work of separating the solid and liquid from the mixture. The screen comprises of mesh clot that is attached to a frame using tension. This is usually used for separating very large solids from the liquid. The slurry that is obtained is stored into a tank and then again sent for further filtering to a mud cleaner.
2) Mud Cleaner :
A mud cleaner combines two processes of desanders and desilters. Here they use a device that separates sand and silt particles from the drilling fluid. As these sand particles are fine, they cannot be removed by a shale shaker. Desander is used for removing solids that are abrasive in nature and dedilters are used to remove silts. The resultant mixture is then sent to a Decanter centrifuge.
3) Decanter Centrifuge :
It is a fast rotating device that uses centrifugal force and sedimentation principle to remove the solid particles from the drilling fluid. Here the machine is rotated very fast so that the solid which is of high density is forced to go out and the liquid which is of less density is forced to go at the center.
After the mixture is separated, the drilling fluid that is obtained can be reused as a drilling fluid. This not only saves the cost but also helps to prevent the wastage of our limited natural resource.
Also the solid that are obtained are first dried before disposing them or resuing thwm for some special purposes.
Thus some part of the drilling waste cuttings is reused and some part of it properly disposed in an ecofriendly manner.