New Carbon Sanitization

When it comes time to replace your carbon media, there is some preparation that needs to be done and it’s critical to properly condition and sanitize it to ensure optimal performance and water quality.

Once you have your new carbon media in place, it is time to prepare it by first soaking the carbon.  Make sure the carbon is fully submerged by filling the vessel with water and letting it soak for a minimum of 8 hours. By doing this, it removes the air pockets from the carbon, and total de-aeration may take over a week to complete.

When your carbon is done soaking, it is time to initiate a backwashing cycle to remove fines and to properly stratify the carbon bed. While backwashing, you should ensure a minimum of 30% bed expansion. Flow rate should be done gradually until the desired flow rate has been achieved.

Once you have reached the desired flow rate, the backwashing cycle should be continued until the water runs clear for at least 20 minutes, but here at Complete Water Solutions, we recommend 30-60 minutes. A turbidity test should be conducted to inspect the water fines and ensure water clarity throughout the backwashing cycle. Using a white cup to confirm water fines have been removed can also be performed.

The next part of the process is sanitization of your new carbon media. The two primary methods for sanitization are steaming and hot water sanitization.

Steaming is a highly effective method for GAC (Granular Activated Carbon) sanitization, reaching temperatures that kill most microorganisms, including thermophilic bacteria and penetrates areas where hot water would not contact.

Carbon needs to be heated completely to 85°C (180°F) with steam cycles running for 8-10 hours at temperatures above 105°C (220°F). The maximum steam temperature should not exceed 110°C (230°F), as damage can occur to the system.

Once the steaming cycle has completed, the vessel should be backwashed to remove debris and fines. Ensure face piping and valves are sanitized by exercising them to expose all wetted surfaces.

Steaming penetrates areas that hot water may not reach, this is especially useful for thorough sanitization in larger complex systems

Cycle steps to remember include Backwash, Settle, Heat-up, Steam, Cool Down, and Refill. Condensate should be removed during a cycle, and upflow steaming is preferred for more effective results.

Hot water sanitization, while different also provides effective GAC treatment and Biofilm control.

Temperature and recirculation: Hot water should be at minimum 85°C (180°F); recirculating through the vessel until the exit temperature reaches 82°C or higher. When exit temperature is 82ׄ°C or higher, continue this process for 1-3 hours for new media, or longer (4+ hours) for older, compacted media.

During the recirculating process, the vessel is filled, ensuring maximum contact with the GAC surface and internal component. Sample ports should be opened briefly during recirculation to expose all parts to heat.

During the cooling phase, hot water is pushed out to the drain and gradually cooled for a minimum of 45 minutes to an hour. After hot water is pushed out to drain and has cooled, you need to backwash the system and rinse it to clear any remaining carbon fines of dislodged biofilm.

When granular activated carbon is installed, it’s not uncommon to see pH rise at startup. This can vary based on source water and carbon surface chemistry.

To manage pH, you can run the drain, fill and soak cycles to help expedite stabilization. In severe cases, acid adjustment can lower inlet pH to speed up stabilization.

By ensuring thorough and effective sanitation practices, you can enhance long term performance and reliability of your industrial water systems whether it’s through steaming or hot water sanitization.

Work with the Experts at Complete Water Solutions.

New carbon installation isn’t just about filling a tank—it’s about ensuring system longevity and water quality from the start. At Complete Water Solutions, we offer expert guidance in system selection and GAC preparation. Get customized support for your water and treatment goals. Industrial problems require industrial solutions. Contact us today to get expert assistance and ensure your new carbon system is ready for long-term performance.