Pennsylvania Facility Successfully Tests Chlorine-Free Wastewater Treatment Solution

What Happened

Kemira has concluded the first full-scale U.S. trial of its chlorine-free wastewater treatment technology, KemConnect DEX, at a Pennsylvania facility. The month-long trial was performed in partnership with Capital Region Water, the utility provider for the Harrisburg area. The technology utilizes performic acid (PFA) as a sustainable alternative to traditional chlorine-based disinfection methods.

Performic acid (PFA) is generated on-site by combining formic acid and hydrogen peroxide in a controlled reaction. Unlike pre-manufactured chlorine solutions that require hazardous material storage and handling protocols, PFA is produced on demand at the point of use. This eliminates the need for large chemical storage tanks and reduces the facility's OSHA-regulated chemical inventory. The compound's rapid auto-degradation into formic acid, water, and oxygen means no harmful disinfection byproducts—such as trihalomethanes (THMs) or haloacetic acids (HAAs)—enter downstream waterways.

Capital Region Water, which serves approximately 62,000 customers in the Harrisburg metropolitan area, selected PFA specifically because its existing chlorine infrastructure was aging. Upgrading to ultraviolet (UV) treatment would have required an estimated $4–$8 million in capital expenditure for reactor installation, power supply upgrades, and ongoing lamp replacement costs. The PFA system, by contrast, integrates with existing piping and requires significantly lower upfront investment.

The trial focused on demonstrating the efficacy of performic acid in a real-world municipal setting. According to the report, the system effectively managed bacterial levels while addressing the operational challenges typically associated with traditional chemical disinfection in the wastewater sector.

Why It Matters

Under the EPA's Clean Water Act, publicly owned treatment works (POTWs) must meet National Pollutant Discharge Elimination System (NPDES) permit limits for fecal coliform and E. coli before discharging treated effluent. Chlorine-based disinfection has been the industry standard for decades, but growing concerns over chlorinated byproducts—particularly in waterways supporting aquatic ecosystems—have pushed regulators toward stricter total residual chlorine (TRC) limits. Facilities exceeding TRC limits face potential fines and mandatory dechlorination steps.

The Harrisburg trial data suggests PFA achieves equivalent bacterial kill rates at concentrations as low as 1–2 mg/L, with complete degradation within 15–30 minutes of application. For comparison, chlorine contact times typically range from 15–60 minutes at 2–5 mg/L, followed by dechlorination with sodium bisulfite—an additional chemical step that PFA eliminates entirely.

Disinfection is a critical stage in wastewater management, but traditional chlorine methods can leave persistent chemical footprints in local water supplies. Performic acid offers a different chemical profile; the solution auto-degrades into biodegradable compounds. This reduces the persistence of chemicals in the environment after the treatment process is complete.

For facility managers, the trial data indicated that the performic acid solution was effective even at low doses. This high level of efficacy suggests that plants can maintain regulatory compliance regarding bacteria levels while utilizing a more environmentally sustainable chemical agent.

Key Details

The KemConnect DEX system integrates a digital platform designed to modernize existing infrastructure. This platform automates chemical dosing by reacting to real-time data, which is particularly beneficial during specific operational scenarios:

• Sudden fluctuations in water flow caused by weather events.
• Rapid changes in influent water quality.
• Maintaining bacterial limits without manual dosing adjustments.

By installing the platform on-site, the facility was able to implement these upgrades without the significant capital investment usually associated with large-scale chlorine system overhauls or the installation of ultraviolet (UV) treatment systems.

What To Watch Next

The success of this Pennsylvania trial may signal a broader shift toward chlorine-free microbial control in the U.S. wastewater market. As municipal and industrial facilities look for ways to modernize aging infrastructure, the adoption of automated, performic acid-based systems could become a preferred alternative to capital-intensive UV projects.

Stakeholders should monitor how digital dosing platforms continue to integrate with existing plant SCADA systems to optimize chemical consumption. The ability to maintain bacterial limits during volatile weather events will remain a primary metric for evaluating the long-term viability of these sustainable alternatives.