The system has provided continuous, quality feedwater to a downstream reverse osmosis system downstream for almost a year
Dow Water & Process Solutions, a business unit of The Dow Chemical Co., is demonstrating its dedication to research and development (R&D) through investment in progressive product piloting. As part of this continued research, the company has announced the results of a recent piloting focused on DOW ultrafiltration technologies, which was carried out at its Global Water Technology Center in Tarragona, Spain, and has seen continuous, excellent quality feedwater supply to the reverse osmosis system downstream over a prolonged period.
The pilot program aimed to monitor the quality of the feedwater produced by the ultrafiltration system, in order to provide support for the company’s range of ultrafiltration technologies, reinforces its ongoing dedication to R&D and improvement of its products and solutions. The data generated is used both to prove the success of its existing solutions, and to validate and qualify new products before their launch into the market. The results of piloting confirm the sustainable and stable operation of the commercial modules as a pretreatment for the reverse osmosis system downstream for more than 300 accumulated days, demonstrating their success in a real wastewater reuse application with relatively high organic content.
In order to provide real wastewater conditions, the pilot system was fed with secondary effluent from the Vilaseca (Tarragona, Spain) municipal wastewater treatment plant. Typically, due to wastewater feed quality and characteristics, the reverse osmosis system cannot be fed directly from the secondary effluent of the wastewater treatment plant without interruption. Therefore, to guarantee the required feed quality to the Reverse Osmosis system, a DOW Ultrafiltration SFP-2880 system was integrated upstream.
The autopsies carried out on the ultrafiltration modules following the end of the piloting demonstrated the absence of broken or damaged fibers, as well as no reported loss in tensile strength and mechanical properties. Based on these test results, it can be concluded that these elements are suitable pretreatment for reverse osmosis systems. The permeate produced by the system downstream is suitable for a number of applications, including irrigation, agriculture and golf courses. Precisely, the agricultural sector represents 80% of water use in the country, so integrating advanced technologies into the sector can help increase efficiency.
Another important finding from the study is the associated cost reduction resulting from the combination of DOW’s ultrafiltration and FILMTEC reverse osmosis technologies. For instance, the ultrafiltration systems require a smaller footprint when compared to other methods of conventional pretreatment technologies, such as sand filtration. In addition, less chemical cleanings are required in the reverse osmosis system downstream due to the more suitable feed water provided by the ultrafiltration system, resulting in longer membrane life, higher plant availability and lower replacement rate of cartridge filters.