Tackling the U.S. Waste Infrastructure with Supercritical Water Oxidation

By Kobe Nagar

Future Cities

With cities projected to accommodate nearly 70 percent of the world’s population by 2050, local and state officials are working to implement more sustainable and resilient sanitation practices and infrastructure. This is primarily for the purpose of maximizing the protection of natural resources and providing a healthier environment for citizens. These efforts will become increasingly important, especially considering that cities account for 60-80 percent of global energy consumption and at least 70 percent of carbon emissions despite only occupying 3 percent of land.

Resource Management

One concept gaining prominence as a guide for cities to limit carbon-emissions and regenerate nature is the notion of a circular economy. According to the United Nations, a circular economy is one in which products and materials are “designed in such a way that they can be reused, remanufactured, recycled or recovered and thus maintained in the economy for as long as possible.” The benefits of establishing a circular economy are substantial; by promoting reuse and recycling, cities can save money, reduce pollution, and encourage innovation.  

Clean Water Act

In the United States, a great deal of environmentally-conscious legislation has accumulated making now the opportune time for the pursuit of a truly circular economy. The Clean Water Act, enacted 50 years ago, provided the first comprehensive basis for wastewater standards. The Clean Water Act dictated that wastewater must be treated so at least 85 percent of certain pollutants are removed before it can be discharged. The Act significantly decreased pollution concentrations in water, which can partially be attributed to the federal grants that were given to municipal wastewater treatment plants.

Investing in Smart Infrastructure

Today, new legislation provided by the Bipartisan Infrastructure Law has further expanded the opportunity to replace outdated infrastructure with better tools to promote a circular economy. The law provides the EPA upwards of $50 billion to improve the nation’s drinking water infrastructure, including wastewater treatment. For example, thanks to the Bipartisan Infrastructure Law, the EPA was recently able to award a $221 Million Water Infrastructure Finance and Innovation Act loan to New Jersey for water infrastructure upgrades. As a result, local projects will be funded to improve treatment capacity and provide more efficient treatment at wastewater facilities. This loan exemplifies the benefits made possible by the Bipartisan Infrastructure Law when allocated to advance circular economy objectives. 

PFAS Crisis

One way in which updating wastewater facilities and treatment plans enhances sustainability is by managing PFAS, or  “forever chemicals.” PFAS are a group of  non-biodegradable chemicals that contaminates the environment and the human body. It is difficult to eliminate, primarily because of how pervasive it is. PFAS are used to make products that resist heat, oil, stains, grease and water, and can be found in consumer goods ranging from non-stick cookware, waterproof clothes, to cosmetics. 

Despite their use for decades, the impact of PFAS on the environment and the human body has not been fully addressed. It continues to be studied in the risks they pose to health. In fact, a recent review from the U.S. Centers for Disease Control and Prevention has found a wealth of health effects associated with PFAS exposure. This includes cancer and liver damage, decreased fertility, and increased risk of asthma and thyroid disease. 

Consequently, municipalities are beginning to turn to innovative wastewater treatment solutions to protect public health. One particular approach to treating PFAS involves reevaluating existing systems for wastewater treatments and exploring new technologies that will treat sludge, biosolids, agricultural, pharmaceutical, and chemical wastes more effectively. 

“SCWOification”

Supercritical water oxidation, commonly referred to as SCWO, is a physical-thermal process powered by water above its critical point and air that create a highly effective oxidation reaction. Through this process, waste is converted to clean water, energy, and minerals, while completely eliminating organic emerging contaminants of concern like PFAS. This effect strongly distinguishes SCWO from traditional means of waste management often utilized by municipalities. These other treatment methods include landfilling, anaerobic digestion, and incineration, which do not successfully contain or eliminate PFAS. 

Technologies employing supercritical water oxidation serve as a transformative tool for cities looking to better pursue a circular economy. Although stringent regulations against the use of PFAS have been implemented, it may take an extensive period of time to see the effects due to PFAS’ ubiquity. Therefore, a more viable solution can be the treatment and elimination of PFAS through wastewater treatment and supercritical water oxidation. By reducing the amount of PFAS in wastewater, SCWO enables cities to achieve their sustainability goals and protect public health, as well as the environment. 

Dare to Transform

In all, the nation is at a precipice to dramatically transform the ways in which our infrastructure supports environmental goals. As part of their efforts, cities should commit as leaders in sustainability to minimize the potential damage caused to the environment and our health, highlighted by the current PFAS crisis. Thus, progress can be accomplished towards a zero-waste world and the ultimate goal of a true circular economy. 

Kobe Nagar is CEO of 374Water.