Industry-Knowledge

How to install a pre-fractionated column for a sewage pump

Installing a pre-fractionated column (also called a separation or deaeration column) for a sewage pump system helps separate gases, solids, and liquids to improve pump efficiency and prevent airlock or clogging. Here’s a step-by-step guide:


Tools & Materials Needed

  • Pre-fractionated column (sized for your pump capacity)

  • PVC or stainless steel piping (compatible with sewage)

  • Check valves & gate valves

  • Vent pipe (for gas release)

  • Pipe sealant (Teflon tape or thread compound)

  • Wrenches, pipe cutter, level

  • Rubber couplings or flange adapters


Installation Steps

1. Choose the Correct Location

  • Install the column before the pump inlet (suction side).

  • Ensure vertical alignment (critical for proper separation).

  • Allow space for maintenance access.

2. Connect Inlet Pipe (From Sewage Source)

  • Use a gradual downward slope (1–2%) to prevent air pockets.

  • Install a gate valve before the column for flow control.

3. Mount the Column

  • Secure the column vertically with brackets or a support frame.

  • Ensure the outlet (bottom) connects to the pump inlet.

4. Vent Gases

  • Attach a vent pipe (top of the column) to release trapped gases (methane, H₂S).

  • Route the vent safely outdoors or to a treatment system.

5. Connect to Pump

  • Use a flexible coupling to reduce vibration transfer.

  • Install a check valve after the pump to prevent backflow.

6. Test the System

  • Fill the column with water to prime it.

  • Run the pump and check for:

    • Smooth flow (no gurgling = proper deaeration).

    • No airlocks (adjust venting if needed).

    • Leaks (tighten fittings as required).


Key Considerations

✔ Column Sizing – Must handle peak flow rates (consult manufacturer specs).
✔ Material – Stainless steel or reinforced PVC for corrosive sewage.
✔ Solids Handling – For high solids, add a grinder pump upstream.


Troubleshooting

IssueSolution
Pump loses primeCheck for leaks; ensure column is full.
Gurgling noiseIncrease vent pipe diameter.
CloggingInstall a pre-filter before the column.

Why Use a Pre-Fractionated Column?

  • Prevents airlocks in centrifugal pumps.

  • Reduces wear by separating abrasive gases/solids.

  • Improves efficiency in wastewater systems.