ICIS Innovation Awards: Dow Chemical wins CSR category

Dow Chemical’s award-winning entry saves water and energy through an innovative collaboration to recycle municipal wastewater  
Mark Whitfield/London

THE ICIS Best Innovation in CSR Award was won by Dow Chemical for its project to reuse wastewater from the town of Terneuzen, the Netherlands, at its Dow Benelux site. This proves that nontraditional wastewater streams can be viable and affordable sources for industrial use, delivering value to both Dow and the community.

Since February 2007, 7,500m3 of cleaned wastewater from the Terneuzen community has been reused daily.

“This project is critical to the Terneuzen site and a demonstration of how sustainability goals can be achieved through collaboration,” says Margaret Walker, vice president, engineering solutions and technology centres at Dow. “Water is an essential component in the running of Dow’s plant and is scarce in the region. We have looked at how things can be done differently and built a solution on previously nonviable wastewater.”

The US chemical giant’s Terneuzen site uses 60,000m3/day of water. Half of this is provided by recycling water streams, process water and rainwater. As part of Dow’s 2015 sustainability goals, the facility is seeking to reduce freshwater intake by 35% compared with 2005.

EVIDES PARTNERSHIP 

Evides is the utility company in the region responsible for treating and supplying water to industry and for domestic use. It acts as the intermediate between Dow Benelux and the Zeeuws-Vlaanderen waterboard, which owns and operates the public water infrastructure in the 1,200km2 (463 mile2) region.

Dow Benelux began collaborating with Evides and the Zeeuws-Vlaanderen waterboard in 1990 to address the scarcity of freshwater in the region. The collaboration provides a sustainable water supply through the reuse of municipal wastewater from the 55,000 inhabitants of Terneuzen.

Wastewater is recycled by Evides into demineralized water and passed to the Dow Benelux site, where it is used twice – first to produce steam and, second, as recycled water in the cooling tower.

Many additional benefits have accrued from the project, including a 65% reduction in energy use by avoiding the need for Evides to desalinate seawater reduced environmental impact through less frequent chemical cleaning of membranes reduced effluent discharge into the River Scheldt and affordable production and distribution of demineralized water through the use of existing regional piping infrastructure and adapting existing membrane equipment.

According to Niels Groot, water/wastewater specialist at Dow’s environmental technology center, around one-third of the 35% target reduction has already been achieved through the municipal wastewater project and through increased internal recycling of rain and stormwater. “The project has been presented to the public in Terneuzen emphasizing the collaboration between the three distinct organizations. The work has been well received and all of the community is behind the initiative,” Groot adds.

“The approach is now being expanded to other Dow locations, for example in Louisiana, in the US, and in Argentina,” says Walker. “Once we find something that’s going well, then we look for opportunities to leverage the experience in other areas. We’re looking to get things to work in novel ways through collaboration and involving the community. Private-public partnerships can work successfully in other regions.”

For example, Dow Water Solutions recently worked on the 2008 Olympic Games in Beijing to maximize the use of water, where it looked for original and useful alternative solutions. Filmtec membranes were installed at three wastewater reclamation and reuse facilities, treating an estimated 45,000m3/day of water, the largest volume of municipal wastewater in Olympic-related projects.

POLLUTION REDUCTION

The Terneuzen site has been working actively on its water strategy for many years and successfully reduced the discharge of organic pollutant equivalents into the Scheldt from 950,000 in 1971 to 50,000 20 years later. “We have made huge steps in the past in reducing organic loads by a factor of 20. This is one of the keys to success. We need to control the whole of the water chain both internally and externally,” says Groot.

“Sustainability goals have engendered a culture of continuous improvement,” says Walker. “Raising the bar is part of the culture at Dow and we are looking for further collaborations to achieve even more.”