Guest Column | May 3, 2024

Reducing Wastewater Hauling Through An Advanced Membrane Treatment Technology

By Chris Roy


High-strength wastewater is often hauled away to be managed, treated, or disposed of off-site, especially in applications like manure digestate and landfill leachate treatment, where strict regulations require the removal of contaminants before disposal or reuse. Hauling wastewater is one of the most expensive and least sustainable means of managing wastewater, significantly impacting the environment through carbon emissions, and drastically increasing operational costs.

As industries strive to meet environmental and economic goals, finding sustainable wastewater treatment methods is needed — now more than ever.

Challenges With Hauling

The logistics of wastewater hauling faces several challenges, the most significant being the high costs associated with its transportation. Unlike electricity or drinking water, which can be transmitted efficiently over long distances, wastewater that is unfit for sewer discharge is much more difficult and costly to transport. And complying with ever-tightening regulations can be difficult as well as costly due to surcharges or fines. These challenges include:

High Costs

The costs of wastewater hauling can be significantly high, influenced by things such as distance traveled, the frequency of hauling, the volume of wastewater being transported, fuel costs, and tipping fees at the offloading sites. For facilities near a wastewater treatment plant (WWTP), distance isn’t an issue, but many remote sites face the challenge of having to haul wastewater over longer distances, costing well over $0.10/kilogallon (kgal) and in some cases even approaching $0.20-0.30/kgal. Additionally, many WWTPs are increasingly restricting or outright refusing to accept many of these streams due to tightening regulations governing their operations and over concerns like PFAS contamination in landfill leachate.

Environmental Risks During Transport

Hauling wastewater poses significant environmental risks, including potential spills that can pollute soil and water, harming ecosystems and posing health dangers to communities and wildlife. These risks were highlighted by the 2023 train derailment in East Palestine, Ohio, which further raised community concerns about the safety and environmental impact of transporting hazardous materials.

PR & Community Impacts

Wastewater hauling can damage a company’s public image and reputation, especially when heavy trucking through residential areas is a constant occurrence. The frequent trucking not only increases community concerns about potential accidents and environmental spills, but also leads to increased noise levels, road damage, and overall safety concerns.

The cumulative effect of noise, potential accidents, environmental risks, and road damage can severely tarnish a company's image and impact growth. Stakeholders, including customers, potential investors, and partner companies, may view the company as a source of local disruption and risk. Over time, this can lead to decreased trust and confidence in the company, affecting its ability to operate effectively within the community. It can also severely limit plant expansion plans that require local approvals.

Energy Consumption and Carbon Footprint

The process of wastewater hauling consumes high quantities of diesel fuel and greatly increases carbon emissions. Requiring substantial fuel consumption, it adds to the overall environmental impact of wastewater management. As companies increasingly focus on their carbon footprints from the board level down and plant carbon intensity (CI) scores increasingly drive economic outcomes, reducing wastewater hauling is becoming a major way to achieve companywide emissions targets.

Advantages Of Treating On-Site

Treating wastewater on-site offers several enticing advantages for both businesses and communities. It enables businesses to comply with local regulations more effectively, while simultaneously improving their public image by showing a commitment to environmental responsibility. Treating on-site also provides companies with enhanced control over their treatment process, ensuring the water they discharge meets limits and helps avoid unexpected fines and surcharges.

In terms of costs, reducing or eliminating the need for wastewater hauling can substantially reduce overall operational costs. Moreover, on-site treatment lowers the environmental impact of wastewater treatment by lowering energy use and carbon emissions from hauling. And in some applications, like in meat and poultry processing, treating wastewater in a chemical-free manner can open the possibility of selling or repurposing organic material as a cost neutral or even a revenue generating stream instead.

An Emerging Technology In Wastewater Treatment

Advancements in wastewater treatment technologies that unlock on-site treatment of these streams are essential for the industry to adopt and support. Membrane filtration, which uses a semi-permeable barrier to filter out impurities from water, has been the most cost-effective method in the past, but has seen only incremental material science innovation over the past 40 years.

With the introduction of new technologies, such as spiral-wound superfiltration membranes, wastewater treatment is on track to become more productive, less expensive, and more sustainable — changing the industry for the better.

Zwitterionic Superfiltration

Superfiltration (SF) is a membrane class that falls between nanofiltration (NF) and ultrafiltration (UF), combining the best qualities of both — high organic rejections and low-pressure operation. Zwitterionic SF membranes offer enhanced treatment capabilities and allow for more efficient removal of contaminants. By letting water and certain solutes like salts pass through its barrier, while blocking larger molecules and contaminants without clogging, this technology has a wide range of applications — including in high-strength wastewater treatment.

In manure digestate applications, zwitterionic SF membranes are designed to handle the toughest wastewater, resolving disposal challenges and creating value from leftover water and nutrients. Implementing a membrane-based solution for digestate can reduce waste hauling and emissions from land application, allow water reuse for irrigation or livestock, and enable the creation of organic fertilizer from recovered nutrients.

In meat and poultry industries, zwitterionic SF membranes provide chemical-free ways to fully remove fats oils and grease (FOG), proteins, and other dissolved contaminants from wastewater, enabling water reuse at scale, and converting organic byproducts into new revenue streams.

In landfill leachate, zwitterionic SF membranes provide the highest quality of reverse osmosis (RO) pretreatment, removing organic foulants without fouling itself and improving overall clean water recoveries, membrane performance, and lifetime.

Zwitterionic superfiltration membranes use innovative zwitterionic technology to construct a membrane that is immune to irreversible fouling. Operating with high efficiency, requiring less energy, and extending membrane life, zwitterionic membranes help facilities reduce their operational costs and support larger environmental sustainability goals.

The Future Of Wastewater Management

The future of wastewater management is being shaped by various exciting trends and innovations that promise to transform how we treat and reuse water. Advanced treatment technologies like zwitterionic membrane filtration are key in reducing the need for wastewater hauling, which in turn lowers both environmental impact and operational costs. In a world where companies are increasingly being required to improve plant efficiencies and bring down costs while decreasing their carbon footprint, wastewater hauling has become the low hanging fruit.

Chris Roy is a co-founder and director of commercial engineering at ZwitterCo. An expert in polymeric and ceramic membranes, Chris previously worked as a research and development engineer and field engineer for Veolia CeraMem and the ALSYS Group, where he piloted, commissioned, and supported numerous industrial wastewater treatment projects in the food and beverage, metal finishing, oil and gas, and aerospace industries. He graduated summa cum laude from the University of Massachusetts Amherst with a BS in chemical engineering and with departmental honors of greatest distinction for his independent research in polymer rheology.