In dissolved air flotation, fine bubbles attach to impurities and float them to the surface of the water being treated.

DAF technology can contribute to more efficient wastewater treatment, reducing operating costs

Treating wastewater can be an expensive proposition. With the industrial sector feeling pressure from strict regulation, and the cost of operating plants and updating infrastructure, it’s important to control expenses wherever possible.

Wastewater treatment systems are typically energy-intensive, consuming substantial amounts of expensive electricity to operate aeration systems, pumps, and other treatment processes, so optimizing efficiency to reduce both the carbon footprint and operating costs of plants is essential.

Dissolved air flotation (DAF) is a versatile and proven technology used across various industries for removing suspended solids, oils, greases, and other contaminants from water. DAF systems release a stream of tiny bubbles into the wastewater. The bubbles attach to particles, carrying them upwards as they ascend to the surface, where they are skimmed off.

Because DAF is more effective than many conventional pretreatment options, such as filtration systems, and requires less cleaning and maintenance, it offers a cost-effective pre-treatment option for removing lightweight particles that do not readily settle out. Its ability to handle large volumes of water while efficiently removing contaminants makes it a popular choice for a wide range of industrial applications.

Improved System Efficiency

DAF systems offer an extremely efficient solution for primary treatment, protecting and optimizing downstream treatment processes, making them more efficient. Fluence’s DAF technology is designed to maximize system efficiency, providing a cost-effective solution for industries looking to reduce operating costs while maintaining high treatment standards. How can you lower your operating expenditures and increase sustainability?

• Enhanced system efficiency: DAF systems remove fats and oils, suspended solids, and other hard-to-remove contaminants, thereby improving process efficiency downstream. By removing these typically stubborn contaminants, the quality of the water entering processes is enhanced, resulting in less energy used in biological treatment. It also helps to protect equipment such as pumps and the aeration system, resulting in lower maintenance costs.
• Increasing energy efficiency: By installing energy-efficient compressors or variable-speed drives (VSD) to generate microbubbles, wastewater treatment plants can reduce the electricity used, thereby reducing energy costs. Using energy-efficient pumps to recirculate water and air, and optimizing pump capacity according to system demand, can also lower energy consumption, resulting in further cost savings. The pump VSDs are designed to keep up with fluctuations in incoming flows to help conserve energy during periods of lower demand.
• Reducing maintenance costs: Optimizing the efficiency of compressors and pumps used in DAF systems also reduces mechanical stress on components, resulting in less wear and tear. This means less frequent breakdowns and repairs, and extended equipment lifespans, reducing costs associated with maintenance and equipment replacement.
• Optimizing chemical usage: A DAF system can enhance flotation, reducing the amount of chemicals (coagulants and flocculants) required to facilitate the removal of solids. This in turn reduces the costs associated with buying and handling these chemicals.
• Smart Operations: Advanced control systems and automation allow dynamic adjustments to system parameters, such as pump speed and air injection, based on real-time water quality conditions. This helps match the treatment process with current operational needs, minimizing energy wastage. Fluence’s Smart Operations data analytics software ensures the system runs optimally, lowering energy and chemical consumption. Smart automation not only optimizes energy and chemical consumption, but also reduces the need for manual intervention, cutting down labor costs associated with system monitoring.
• Reduced sludge production: DAF systems produce less sludge than other treatment methods, minimizing disposal costs associated with transport and handling, a significant expense for many plants.

A Closer Look at DAF Systems

Fluence installed a DAF system with a capacity to treat 6,600 gallons/hour (25 m³/h) for Ekolat, a mozzarella cheese plant in Slovenia. The plant, which processes 34,340 gallons (130,000 L) of milk per week, needed to remove grease and proteins, and lower the organic load of wastewater effluent before it could be sent to a municipal wastewater treatment plant for treatment. DAF’s efficiency at removing suspended fats, oil, and grease, and reducing COD and BOD made it a robust and cost-effective solution.

An Italian poultry processing plant that wanted to increase production while reducing operational costs turned to Fluence for a customized solution for treating their process water, which had a high and variable organic load. Fluence upgraded the existing wastewater treatment plant to include DAF pretreatment, which resulted in a 97% reduction in total suspended solids and an 80% reduction in COD, together with anaerobic digestion to facilitate waste-to-energy production. With the upgrades, this plant is now able to treat high-COD wastewater, significantly reduce sludge levels, and generate energy that is used on-site to run the plant. The plant’s wastewater effluent meets strict European Union regulatory standards for discharge into the environment.

Improving efficiency in wastewater treatment can have a direct impact on operational costs through lower electricity bills, reduced maintenance, optimized chemical use, and more efficient system design, resulting in improved sustainability and significant financial benefits over time. Fluence’s DAF wastewater treatment plants offer a valuable solution for industries looking to reduce costs while maintaining high standards. Our systems are compact, robust, easy to operate and maintain, and are designed with the flexibility to handle a wide range of influent quality and flow rates.

Contact Fluence to learn more about our DAF systems and other wastewater treatment solutions.