Sizing
Back Pressure
Final compression, as a design and sizing factor
Back pressure is the resistance applied at the discharge that compresses the cake. In design it determines the achievable cake solids and influences the required drive torque.
Compression in the machine design
The back-pressure device — a plate or cone at the discharge — works with the narrowing screw pitch to compress the cake plug. A design with sufficient compression capability and drive torque can reach higher cake solids across a range of sludges. In operation, back pressure is trimmed to each sludge; in sizing, it is the machine’s ability to apply and sustain that compression that matters. Excess pressure is limited by the point at which fines are forced into the filtrate.
RF Series Screw Press
Sludge Cake Discharge
The dewatered cake drops into a discharge trough — ready for a conveyor, container or skip.
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