GN Vertical Cuttings Dryers for Drilling Waste Management

Efficient drilling waste management involves more than simply removing drilled solids from the circulating mud system. When oil-based mud (OBM) or synthetic-based mud (SBM) is used, discharged cuttings can retain a significant amount of valuable drilling fluid. A vertical cuttings dryer provides a secondary separation stage designed to recover this fluid while reducing the volume and liquid content of the remaining solids.

The GNCD930 Vertical Cuttings Dryer uses centrifugal force to separate drilling fluid from cuttings. Wet cuttings enter the dryer and are accelerated inside a stainless-steel screen bowl rotating at speeds up to 900 RPM and generating forces up to 420 G. Liquid is forced through the screen openings while the separated solids are continuously moved through the machine by the rotor flights.

For oil-based drilling cuttings, the GNCD930 is designed for a processing capacity of approximately 30–50 tons per hour. Depending on the drilling conditions and characteristics of the material, oil on cuttings can typically be reduced to approximately 3–5%.

Field performance is an important part of evaluating any solids-control process. The accompanying GN operation record shows incoming cuttings containing approximately 13–19% oil over a 21-day operating period. Following treatment by the Vertical Cuttings Dryer, the discharged solids remained primarily within the 2–5% range, with one documented sample reaching 2.9% oil on cuttings.

Fluid recovery does not necessarily end at the VCD. Effluent recovered through the screen can be collected in a catching tank and pumped to a high-volume decanter centrifuge for further clarification. The centrifuge removes finer suspended solids, allowing the recovered drilling fluid to be returned to the active mud system when process requirements permit.

A complete drilling cuttings management system can therefore incorporate shale shakers, screw conveyors, the Vertical Cuttings Dryer, catching tanks, transfer pumps and a decanter centrifuge. This approach allows operators to address both sides of the process: reducing liquid retained on discharged cuttings while recovering drilling fluid for potential reuse.

GN Solids America can provide the GNCD930 as a standalone Vertical Cuttings Dryer or integrate it into a complete drilling waste management system based on specific site, throughput and process requirements.