Xylem Africa has launched a new dissolved air flotation (DAF) water treatment solution. This compact and convenient industrial wastewater pre-treatment system is now available in South Africa for permanent and rental use, backed by expert skills and customisation options.
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The compact and efficient DAF water clarification system is available for permanent and rental use, backed by expert skills and customisation options.
In a recent event hosted at Xylem Africa's headquarters in Kempton Park, Johannesburg, Xylem Africa unveiled its dissolved air flotation (DAF) water treatment equipment and services, which offers reliable wastewater treatment to key sectors such as mining, municipalities, agriculture, aquaculture, food & beverage, paper & pulp, chemical manufacturers and pharmaceutical companies.
DAF is a critical pre-treatment and solids-separation system within broader wastewater treatment systems. It can operate as a standalone solids-separation step or complement downstream biological filtration or reuse systems to help achieve site-specific compliance and reuse objectives. The compact and modular design enables deployment in constricted and crowded sites. Xylem also offers excellent DAF rental options for smaller and seasonal projects.
"We are very excited to bring cutting-edge DAF solutions to our local customers. Xylem has introduced our DAF solutions to several other markets, where they have become a big hit among companies of various sizes. They appreciate the logistical benefits of DAF's compact designs and convenient deployment, supported by our expert technicians. South African organisations in the private and public sectors can now also leverage DAF to expand their choices for water treatment and recycling," says Chetan Mistry, Strategy and Marketing Manager at Xylem WSS (AMETI).
Xylem’s DAF systems use Hellbender™ pumps to release microscopic air bubbles into wastewater, which, following appropriate coagulation and flocculation, attach to suspended and destabilised colloidal particles, enabling their separation from the water phase and flotation to the surface, where they can be skimmed away.
The DAF technique efficiently removes total suspended solids (TSS), fats, oils, and greases (FOG), and particulate-associated biochemical oxygen demand (BOD) from wastewater streams. These systems offer an effective solution for a wide range of applications, including:
- Thickening of biosolids.
- Product recovery from wastewater.
- Treatment of industrial wastewater to meet site discharge limits.
- Polishing of biological treatment effluent (algae and phosphorus removal).
- Pretreatment to reduce loading on downstream biological treatment systems.
- Clarification of biosolids downstream of aerobic and anaerobic treatment.
- Removal of fats, oils and greases (FOG).
- Temporary treatment of biosolids during harvest seasons.
- Removal of metals and fines.
- Recovery of proteins from slaughterhouse wastewater.
DAF systems are also remarkably compact, often requiring significantly less footprint and depth than conventional sedimentation tanks, depending on design and loading rates. Its combination of convenient sizes and broad applications makes it attractive to numerous industries that clean water for reuse, extract materials from water or prepare water for compliant discharge into the environment.
Bringing DAF's advantages to Africa
Xylem's DAF solutions and services enable more producers to manage wastewater strategically without excessive investment in wastewater infrastructure.
As part of a phased and modular treatment strategy, DAF is often deployed as an entry point into integrated wastewater and reuse solutions, enabling future expansion with biological treatment, filtration and advanced polishing technologies.
Xylem's DAF units provide efficient wastewater pre-treatment and solids separation, with three DAF models in the Xylem RT DAF series: the RT-50, RT-100, and RT-240, offering flow rates from 100 to 1 000 GPM. Key features include:
- Superior, clog-free performance: The system delivers superior performance without plate packs, which can foul, collapse or clog, thereby increasing operational uptime.
- The robust, space-saving design features a rugged, heavy-gauge stainless-steel tank (available in 304 or 316 SST) that will not flex, while the tank’s rectangular profile ensures maximum space utilisation.
- Ease of installation: The complete, skid-mounted design means no field assembly is required, simplifying installation.
- Efficient whitewater system: The system uses an industry-leading and HELLBENDER® whitewater system to create very small air bubbles, making the system both efficient and simple to operate.
- Integrated and automated: A large internal float hopper eliminates the need for an external float tank. The system also features an automated float hopper and settled solids auger.
- Optimised chemical mixing: An integral flocculation tube is equipped with three chemical injection ports, designed for optimal mixing of coagulants and flocculants.
- Reliability: Built with quality drive and pump components for long-term reliability.
“From running pilots and proofs of concept for wastewater management plans to enhancing the efficiency of established treatment systems and upgrading to cutting-edge treatment methodologies, Xylem Africa and DAF help South African industries and municipalities solve water for all.
“Xylem Africa and its partners can deliver permanent and rental DAF solutions, calibrated to a customer's specific requirements and operations,” says Mistry.
Xylem's expert staff and experienced partners customise each solution as required. “We deliver and manage components such as mixer tanks, weir tanks, pumps and conveyors, as well as catwalks and accessories. Our skilled technicians can support on-site staff or run the process on behalf of our customers," Mistry notes.
Water is humanity's most essential resource. As water stress and costs increase, organisations are intensifying their strategies to ensure supply and compliance. For many, though, this prospect was out of reach due to the cost and cumbersome ownership requirements of industrialised water treatment options.
Backed by Xylem’s engineering expertise and service capabilities, dissolved air flotation offers flexible, resilient options for wastewater pretreatment and reuse within integrated water management strategies.
