Napier-Reid Services: Pump Station Design, Instrumentation & Control Design, Electro-mechanical Supplies, Installation and Commissioning Support, Operator's Training.
Scope of Supply:
Steel pump station chamber made of epoxy-coated steel; 2.5 m diameter and 6.9m height. The pump chamber c/w inlet and outlet connections, vent connection, hinged access hatch covers and sacrificial anodes to protect the chamber.
ABS submersible Pumps, ( 1-duty, 1-standby ), Pump slide guide rails, Emergency Diesel Pump connection lines 150mm epoxy coated steel with Kamlock connections. Inlet 300mm and Outlet 150 mm epoxy coated steel piping and pipe fittings.
Mid access platform made of aluminum grating with support angles for operator landing and aluminum safety handrail around the access platform, Aluminum access ladder, Explosion proof lights (One - at the grade level, One-at the mid-access platform)
Lot of valves including Three 6 check valves and Three -6" plug valves
Electrical, Instrumentation & Control:
Electric control panel free standing, double-door type, mounted outside for pumps, with weatherproof NEMA 4, Stainless Steel enclosure, 575V/3/60, and maximum 50 KW.
The panel includes Variable Frequency Drive, PLC and Phoenix Ethernet for communication with plant SCADA, Main circuit breaker, Thermal/Leakage protection relays, H-O-A selector switch per pump, Indicating lights push-to-test type, Motor high temperature RESET pushbutton, Surge Protector, UPS, Intrinsically safe relays, External interfaces to the plant PLC for pump status, selector switch position, pump fail alarm and tank high level alarm by Ethernet and not hard wired, Labels, Terminal strips, fuses.
Ultrasonic level transmitter, float type liquid level controls, Explosion proof lights.
Pumping Chamber made of Steel, Variable Frequency Drive.
- Process Description
The pumps station can be operated in two modes; Hand and Auto.
In Hand, the speed of the sewage pump will be manually adjusted by the potentiometer. The pump will run continuously until the sewage level reaches the Low-Low level switch.
In Auto, the sewage pump will run by the PLC based on level set points and the speed of the pump will be adjusted automatically adjusted by an algorithm. The level transmitter will be located inside the control panel. If the ultrasonic level transmitter faults, the PLC will use the float switches signals as backup to control the pumps.
In normal condition the pumps will run as duty and standby. If the sewage pump station level reaches the high-high set point on the transmitter or the high-high level switch is ON, the lead/lag condition will be activated by the PLC until the condition is cleared. The lead/lag condition will be clear when the pump stop level set point is reached or the Pump Stop float switch is reached.
During the lead/lag condition two pumps may run together. The PLC will use a time delay to prevent two sewage pumps from starting instantaneously.
Duplex Wastewater Pumping Station