ZJ30 Mud Solids Control System for a Sichuan Shale Gas Well

TR supplied a drilling mud solids control system for a ZJ30 shale gas drilling project in Sichuan, China. The well was designed to reach 3,000 m and used water-based drilling fluid in a formation with high clay content and fine cuttings.

In this type of formation, drilled solids can build up quickly in the active mud system. Fine clay and cuttings increase solids loading, complicate mud property maintenance, and can accelerate wear on drilling pumps and drill pipe. The system therefore used staged solids removal to control both coarse cuttings and fine solids while keeping treated mud in circulation.

The system was configured for a maximum processing capacity of 240 m³/h, matching the ZJ30 rig's maximum circulating flow.

Drilling Conditions & System Setup

The installation included three mud tanks with a total volume of 240 m³. Two TRZS584 linear motion shale shakers, one TRZCQ300 vacuum degasser, one TRCS250 desander and one TRCN100×8 desilter were arranged on the tank-top platform. The TRLW450 decanter centrifuge was installed as a separate unit.

Explosion-proof electrical control equipment, mud agitators, manifolds and access walkways completed the package.

Returning drilling fluid first passed through the shale shakers to remove coarse cuttings. After degassing, the mud entered the desander and desilter for further separation in the 40–74 μm range. The TRLW450 then handled finer particles in the 2–10 μm range.

After treatment, the mud returned to the tanks for conditioning and reuse.

Field Application of Solids Control Operation

TR commissioned the system before drilling began and checked the separation units, centrifuge and auxiliary equipment during startup.

Throughout drilling, the system handled the returning mud continuously. The staged separation removed coarse cuttings first, followed by finer solids through the hydrocyclones and decanter centrifuge. The treated mud was then returned to the circulation tanks.

The configuration matched the formation conditions and kept fine solids under control during drilling. Treated drilling fluid solids content remained at ≤5%.

Operating Results

The project successfully completed the planned 3,000 m shale gas well, with no shutdown failures reported for the solids control system during drilling.

Treated drilling fluid was returned to the circulation system, reducing fresh mud preparation and associated water-treatment requirements. Lower solids loading also helped limit wear on drill pipe and drilling pumps. Cuttings were collected centrally, while reduced liquid discharge supported the environmental requirements of the Sichuan drilling site.

For this ZJ30 application, the system maintained the mud circulation cycle from coarse cuttings removal through fine-solids separation, conditioning and reuse.