According to the environment protection laws and regulations in many countries, the drilling waste management system is mandatory for a drilling rig’s solids control system. A complete drilling waste management system includes 2 systems, one is to treat the drilling cuttings discharged by the solids control shale shakers, which is used for reduce the cuttings for a safe discharge, and also for recovery of the drilling fluids. The other is drilling fluids waste management, which is used to remove the extra particles in the drilling fluids after a long time recycling in a solids control system.

1. Drilling cuttings waste management system. In a word, this system’s first mission is to minimize the cuttings to be discharged. Based on different mud type, the first separation equipment is different.

1.1. For oil based mud, which is used in most of drilling fields, a vertical cuttings dryer is more efficient. A vertical cuttings dryer is a high speed rotating machine which uses the centrifugal force to splash the liquid to through a mesh while the same mesh is used to block the cuttings. GNCD930 series vertical cuttings dryers can reduce the oil on cutting to below 5%.

1.2. For water based mud, a high G drying shaker is a better choice. It is similar as a shale shaker. And the main differences from a solids control shale shaker are: a high G shaker has a larger G force and the feeding of a high G shale shaker is like a hopper.

2. The second step for separation, for both the OBM cuttings and WBM cuttings is always a high speed decanter centrifuge, which is used to remove the finer solids particles in the liquid after the first equipment’s work. Unless a solids control centrifuge, this centrifuge for drilling waste management is always equipped by a VFD control panel, which is more flexible for variable mud condition.

Next time we will talk about the drilling waste management system.