Klargester BB BioDisc Service & Repair – Balbeggie, Perth

BB BioDisc repair in Balbeggie — We recently carried out a scheduled service and repair on a Klargester BB BioDisc sewage treatment plant in Balbeggie, Perth.

On arrival, the BioDisc was not rotating correctly and the drive belt had come off both pulleys.

The drive belt, top pulley, bottom pulley and locking element had previously been replaced by the previous owners. However, the drive system required further alignment and adjustment before it could operate correctly.

Drive System Fault

The top and bottom pulleys were inspected and found to require realignment before the drive belt could be refitted correctly.

The top pulley was properly secured, both pulleys were aligned and the drive belt was refitted and tensioned correctly.

• Drive belt refitted
• Top pulley correctly secured
• Top and bottom pulleys realigned
• Drive belt correctly tensioned
• Drive system recommissioned
• Normal BioDisc rotation restored

Mechanical Inspection

Once the drive system had been restored, the remaining mechanical components were inspected as part of the scheduled service.

• Drive-end bearing in good condition
• Non-drive-end bearing in good condition
• Motor gearbox operating correctly
• Slight motor gearbox noise noted for future monitoring
• Rotor shaft in good condition
• All rotor clamps present and secure
• Disc pack in good condition

No grease brush was present on the BioDisc at the time of inspection.

Outlet Pump Inspection

The plant is fitted with a Grundfos KP250 outlet pump, which was also inspected during the service.

The pump was removed, cleaned and checked for blockages. No restrictions were found and the pump itself was operating correctly.

However, the existing 1¼-inch non-return valve had failed.

Failed Non-Return Valve Replaced

The failed non-return valve had allowed the outlet pump to repeatedly switch on and off for an unknown period of time.

This unnecessary cycling may have placed additional wear on the pump. Although the pump is currently operating correctly, its service life may have been reduced as a result.

The failed valve was removed and replaced with a new 1¼-inch non-return valve before the outlet pump was fully tested.

Alarm & Electrical Testing

The BioDisc and outlet pump systems were electrically tested following the repair work.

• Supply voltage: 230V
• Motor current draw: 0.59A
• Outlet pump current draw: 2.1A
• High-level alarm tested and operating correctly

Treatment Process Recovery

Because the BioDisc had not been rotating correctly before the repair, the final effluent was cloudy and a septic odour was present.

These conditions are consistent with the biological treatment process being interrupted.

Now that normal rotation has been restored, the biological treatment process should begin recovering naturally. The septic odour should reduce significantly within approximately 24–48 hours, with effluent quality improving as the biomass recovers.

Sludge Levels

• Primary crust: 0mm
• Primary sludge: 100mm
• Final crust: 0mm
• Final sludge: 100mm

Sludge levels were satisfactory and desludging was not required at the time of the service.

System Condition After Repair

• BioDisc rotating correctly
• Drive belt correctly aligned and tensioned
• Outlet pump operating correctly
• New non-return valve installed
• High-level alarm operating correctly
• No further remedial work required

Recommended Future Monitoring

The outlet pump should be monitored during future servicing due to the unknown period of excessive cycling caused by the failed non-return valve.

The slight noise from the motor gearbox should also be monitored during future inspections.

Routine annual servicing is recommended to help identify developing faults before they result in unexpected breakdowns.

We provide Klargester BB BioDisc servicing, drive system repairs, outlet pump maintenance and non-return valve replacements across Balbeggie, Perthshire and throughout Scotland.