Calculation of the required engine torque to rotate the cylindrical shell

Hi engineers! The first time with you, so forgive me if something goes wrong.


The task is as follows. We have a device called a drum filter (see attachments). I need to understand how powerful the geared motor should be so that it can turn the cylindrical shell (the cylinder is the filter itself). The weight of this cylinder is 150 kg. Disregard hinge friction. Diameter 1600 mm, length 2500 mm. In addition, it can be half filled with water. The geared motor must be able to rotate it both dry and half filled with water. I will show the location of the gears in the attachment. You need to understand what power (kW) or with what moment (N * m) a geared motor is needed so that it all rotates. I know how to count as long as the motor shaft is coaxial with the cylinder. Please show me the technique, you can have a ready-made answer, just explain please. So that in the future I can count everything.

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