Screenings and Grit Plant

This Wastewater Treatment Plant treats 57 ML/day of primary sewage from an EP of 210,000. The plant was expanded and commissioned in Dec 2005. The new SPIRAC^® systems include three SPIROSEP Grit Vortex chambers, hydro cyclones, a SANDSEP^® grit classifier, two twin SPIROWASH^® screening washer units, a sluice and conveying system, and two SPIROTAINERs^®.

Grit is pumped from the SPIROSEP^® Vortex Grit chambers through three hydrocyclones and discharged into a single SANDSEP screening classifier. This feeds a common screenings/grit collection conveyor to fill two SPIROTAINERs^®. Screenings from a band screen are transported via launder to twin SPIROWASH® screw-compactors which wash and compact the screenings before elevating the screenings into the collection conveyor. Automatic bifurcated chutes allow bypass to overflow bins if the SPIROTAINER^® is full or absent. The system is completely automated, allowing auto bin changeover, duty/standby operation of the SPIROWASH^®, and full monitoring and functional control.

This screenings and grit plant upgrade in 2006 included the following SPIRAC equipment:

• SPIROSEP^® Vortex grit systems (3) with Grit pump extraction
• Launder (sluice) system to transfer screenings and wash water from screens to SPIROWASH units
• SPIROWASH^® Duplex (2) for high-capacity screenings washing and compaction
• SANDSEP^® Grit classifier fed by three hydro cyclones
• Combined screenings and grit transfer conveyor
• Diverter chutes on screenings and grit feed to the conveyor for emergency bypass
• Two SPIROTAINERS^® for storage, odour containment and road transport