Reactivation

Thermal Reactivation of Spent Activated Carbon

SorbiTech reactivation is the lifecycle service that returns spent granular activated carbon to service at 85 to 95 percent of virgin activity. The spent carbon is shipped to a Medaad partner reactivation plant, processed in a rotary or multiple hearth furnace at 850 to 950 °C in a controlled steam atmosphere, and returned to site after laboratory verification of the recovered iodine number, hardness, and decolorization performance. The cycle takes four to six weeks from collection to return, scheduled around the operator demand profile.

Why Reactivate Rather Than Discard

Reactivation is the deciding economic feature of granular carbon over powdered carbon. The avoided cost of new media plus the avoided disposal of spent media together lower the lifecycle cost of a water filter by 40 to 60 percent compared with single use operation. The carbon mass is reused for 5 to 10 reactivation cycles before make up is required for fines loss; the cumulative effect is a treatment cost per cubic metre of water that is up to 60 percent below the single use route.

Carbon Lifecycle Programme

The reactivation contract includes:

• Scheduled spent carbon collection aligned to the operator backwash cycle
• Thermal reactivation with controlled make up to maintain bed depth
• Laboratory analysis of returned activity (iodine, hardness, moisture, ash)
• Returned material delivered with certificate of analysis
• Logbook for regulatory compliance reporting

The programme is most common in the municipal water treatment sector for taste and odour and dissolved organic carbon polishing.