A centrifuge and a control system therefor

A drilling mud system for separating solids from solids laden drilling mud, includes a centrifuge 10 having a bowl 12 and a conveyor 18, an inlet 18a for solids laden drilling mud to be introduced to the bowl 12. The system also includes a solids discharge outlet 12c and a drilling mud discharge outlet 19', a bowl drive 24 for driving the bowl 12 and a conveyor drive 34 for driving the conveyor 18, the system further comprising at least one sensor and a control system measuring centrifuge performance with said at least one sensor. The control system stores an algorithm for determining optimum performance and said control system: making a small evolutionary operation parameter change in a first direction; checking if the small evolutionary operation parameter change is within constraints; re-measure centrifuge performance, whereupon if the centrifuge performance improves, for making a further small evolutionary operation parameter change in said first direction and if the performance does not improve for making a small evolutionary operation parameter change in a second direction. The centrifuge may also include an adjustable gate 20a, fig 5 and an actuator, where a pond of solids laden drilling is maintained by means of said gate 20a.