Screw conveyer system

A system for treating a material, comprising:

• a first screw conveyor comprising a first rotary shaft and a first helical flight extending radially outward from the first rotary shaft;
• a second screw conveyor comprising a second rotary shaft and a second helical flight extending radially outward from the second rotary shaft, the first helical flight and the second helical flight overlapping;
• a first actuator operably coupled to the first screw conveyor;
• and
• a second actuator operably coupled to the second screw conveyor.

A control system for a multiple-screw conveyor system comprising a first screw conveyor having a first helical flight and a second screw conveyor having a second helical flight, the first helical flight and the second helical flight overlapping, the control system comprising:

• a first screw-position sensor configured to detect a first rotational position of the first screw conveyor;
• a second screw-position sensor configured to detect a second rotational position of the second screw conveyor;
• a first adjustable speed drive operably coupled to a first actuator configured to rotate the first screw conveyor;
• a second adjustable speed drive operably coupled to a second actuator configured to rotate the second screw conveyor independently of the first actuator;
• and
• a controller configured to send a first output signal to the first adjustable speed drive in response to a first input signal received from the first screw-position sensor and to send a second output signal to the second adjustable speed drive in response to a second input signal received from the second screw-position sensor.

A method for cleaning a screw conveyor system comprising a first screw conveyor having a first helical flight and a second screw conveyor having a second helical flight, the first helical flight and the second helical flight overlapping, the method comprising:

• operating the first screw conveyor and the second screw conveyor;
• adjusting a relative rotational position between the first screw conveyor and the second screw conveyor to produce an adjusted relative axial position between the first helical flight and the second helical flight to clean the first or second helical flight;
• and
• maintaining the adjusted relative axial position.