We specialize in on-site support, providing a host of top-notch field services to install and remove carbon in the most efficient and safe manner – maximizing the customer’s economic benefits and minimizing disruptions to the operations.

We started in the 1940s, providing activated carbon solutions for the U.S. military. Over time, we evolved. We became pioneers in drinking water treatment and have a long legacy of solving customer problems for a variety of applications. With more than 75 years of experience, we are trusted, and we are proven.

For its industrial customers, we treat not just water but also the environment. The company offers a wide range of treatment solutions depending on the site challenge and discharge permit criteria. We offer PFAS treatment solutions for wastewater, air, process water, landfill leachate, and groundwater remediation.

Our technical team can assist with testing and simulation to determine the optimal PFAS treatment configuration for municipal and industrial settings.  This collaboration offers the most cost-effective investment process, which helps clients avoid mistakes that could increase the cost and timeline for effective treatment.

Our technical experts know that testing helps them determine the best treatment option. As a result, we perform more tests than any other manufacturer and have more capabilities than our competitors. Thorough testing determines the best course of treatment, including ion exchange or GAC.

Reactivated carbon is GAC that has been thermally treated once it is at the end of its useful service life, when it is known as spent carbon. It goes through a process that vaporizes and destroys adsorbed contaminants at extremely high temperatures and restores the GAC to a near-virgin state so it can be reused.

In reactivation, the spent activated carbon travels through a multi-hearth furnace or rotary kiln, which restores the activated carbon to a virgin-like state. Using thermal treatment at high temperatures of up to 1750 degrees Fahrenheit, this step vaporizes and destroys contaminants in the furnace or kiln itself. The goal of this first step of reactivation is to restore the structure of the activated carbon, and the operating conditions (temperature and steam addition) are tuned for that purpose. 

Any contaminants that survive the high-temperature furnace travel to the abatement system for further destruction. 

The pollution abatement system for reactivation consists of a thermal oxidizer / afterburner, a scrubber, and a baghouse. Our abatement system is designed to destroy organics to meet regulatory limits, typically to at least 99.99% efficiency. The system also neutralizes acid gases formed during the process and captures particulates.

There is carbon regeneration, which uses a lower-temperature treatment – typically below 400 degrees Fahrenheit with steam, nitrogen, or other hot gas – for short periods of time to remove only a portion of the adsorbed contaminants, producing a partially spent carbon that contains some, and potentially all, of the original contaminants.

We do not use the carbon regeneration process, but instead a reactivation process that relies on thermal treatment at high temperatures greater than 1700 degrees Fahrenheit for hours at a time.

Our FILTRASORB^® is a re-agglomerated GAC produced from bituminous coal that has demonstrated superior PFAS-removal capabilities compared to other carbons and acts as a high-performing carbon for a variety of other compounds as well.

We offer a full range of GAC adsorption equipment and activated carbon products to treat PFAS. This simple and effective solution requires little operator involvement. Our equipment is uniquely designed to ensure no water escapes without being in contact with our activated carbon product. In an application with no room for error, choosing the right equipment and the right carbon is critical.

We offer two primary options to meet our customers’ needs and provide the flexibility needed.  The two types of AquaKnight systems are 1) Gold Certified (GC) and 2) Custom Certified (CC).  The AquaKnight Gold Certified, or GC, designation applies to a two-vessel system that is certified in its entirety by the National Sanitation Foundation to Standard 61 (NSF 61) for Drinking Water System Components.  The AquaKnight Custom Certified, or CC, designation applies to either systems or single vessels, where each individual component that is in contact with the water is NSF 61 certified, rather than the entire packaged system.

The AquaKnight GC system is fully NSF 61 certified for the entire system. It provides a more cost-effective and timely approach than customizing and certifying each component.

The numbers represent the size and capacity of each vessel. For example, one of Calgon Carbon’s most frequently requested vessels, the Model 10 system is comprised of two 10-foot diameter vessels, hence the Model 10 naming convention.  Moving forward this system will be referred to as AquaKnight GC 10 (or CC 10) in drinking water applications. 

The data from our stack testing program demonstrate that reactivation of PFAS-laden GAC in a facility operating a multi-hearth furnace with appropriate abatement system results in high levels of destruction of PFAS compounds – including removal of PFAS compounds from GAC and greater than 99.99% destruction of PFAS compounds through the furnace and abatement system.

The most significant finding is the confirmation that not only is PFAS removed from the activated carbon to below detectable levels, but PFAS destruction occurs in the reactivation furnace and robust abatement systems.

Our research is critical in this space. Everyone wants to know what happens to PFAS once they are removed from water. This research demonstrates that, through our proprietary reactivation process, we can remove PFAS from the activated carbon and destroy them to greater than 99.99%. The research is critical in answering the question, “What happens to PFAS once they are removed from the water?”

We contracted with a third-party vendor specializing in manufacturing emissions testing to determine the emission rates of PFAS and hydrogen fluoride per established methodology. Additional outside vendors tested air samples for 36 PFAS compounds and analyzed well water and treated motive water samples for PFAS and analyzed samples of spent carbon, reactivated carbon, abatement dust, and bicarbonate raw materials for extraction and targeted PFAS.