Project Merit: Water Reuse


CDM Smith (Boston, Mass.) for a process water treatment and return plant (PWTRP) designed and built for JR Simplot, one of the world’s largest producers of potato products. CDM Smith’s innovative treatment system included primary clarification, anaerobic fermentation, enhanced biological nutrient removal for nitrogen and phosphorus, and activated sludge with membrane bioreactors followed by reverse osmosis (RO) and chlorine disinfection. All RO brine is evaporated on site in an enhanced evaporation system. The plant, in Caldwell, Idaho, treats an average of 2.3 million gallons per day (mgd) of high-strength potato processing wastewater. Approximately 1.7 mgd of water, equivalent to drinking water standards, is reclaimed for reuse. The technology ALSO won the WateReuse Assn.’s 2016 Industrial Project of the Year award.

Tamilnadu Water Investment Company Limited (Chennai, India), a developer of water/wastewater projects, for a zero liquid discharge (ZLD) common effluent treatment plant (CETP) project with a combined capacity of 53 millions of liters per day (MLD). The plant services a textile dyeing cluster in the district of Tirupur, Tamilnadu, India. Tirupur was the first industrial cluster to implement ZLD in the country. This project recovers 98% of water and over 70% of sodium sulphate salt for reuse in the dyeing units, and is being replicated in other districts with large concentrations of dyeing units. The technology uses membrane distillation instead of thermal multiple effect evaporators and features integration of membrane distillation coupled with a solar thermal system, helping to ensure that the carbon footprint is lower than conventional treat-and-discharge systems. A detailed project report was prepared in 2016, technically evaluated by IIT, Madras, and approved for a grant by the State of Tamilnadu, in addition to passing the first stage of approval for a grant from the federal government.