WBM waste treatment system technical specification:
1) High G drying shaker to separate coarse solids from the drilling waste,
2) VFD decanter centrifuge to separate fine solids from the drilling fluids, the chemical dosing system add chemicals into the waste water to improve the separation performance and efficiency.
The working principal of the decanter centrifuge to separate fine solids from the fluids is as below:
The bowl and the screw ( inside the bowl) rotate by the same direction with a differential speed. the waste water is fed to the screw shaft by the centrifuge feeding pump, under the centrifugal force working, the solids desposited to the bowl wall and the solids is continuously pushed to the cone section of the centrifuge bowl and discharged to solids distribution port. Because of the gravity difference, the fluids overflows to the liquid distribution port which is in big end of the bowl. The straight bowl material is made of duplex stainless steel 2205 or 2304 by centrifugal casting, as clarification phase, the cone section is made of stainless steel 316L, which is as extrusion drying area. To adjust the differential speed by VFD control panel is very important operation for VFD decanter centrifuge, it will influence the decanter centrifuge separation performance a lot, the user should read the operation manual carefully and to be trained to input correct differential speed by the touch screen and controlled by PLC smart control.
The flow rate can be controlled by adjust the frequency of pump motor. When start the decanter centrifuge, the flow rate should be set properly in case that high flow rate lead the too high electricity currency which will burn the motor.
After treated by decanter centrifuge, most of the ultra fine solids up to 1 microns will be separated out and get relative pure water.