High Water Recovery and Reduction of Chemical Oxygen Demand (COD) in Industrial Wastewater
A major US consumer goods producer generates wastewater with chemical oxygen demand concentrations (COD) of approximately 15,000 mg/l. The customer wanted to reuse 90% of the wastewater with a maximum COD value of 2,000 mg/l in the treated product.
These criteria could not be met using traditional polymeric membranes because the elevated concentration of surfactants in the feed water would lead to rapid fouling and require high frequency cleaning cycles. The pre-treatment system necessary to mitigate fouling of polymeric membranes was capital intensive and expensive to operate for the target flow rate of 100,000 gallons per day.
Reduction of Chemical Oxygen Demand (COD) in Aquaculture Wastewater Combined with High Water and Nutrient Recovery
Aquaculture can have many positive benefits on food sustainability and conservation of fisheries. However, sustainable aquaculture operations require successful management of wastewater streams to avoid negative impacts on the environment. Recognizing the need to be a good steward of the environment, an aquaculture facility located on the coast of New England is committed to treating its wastewater to protect the receiving water bodies while recovering valuable byproducts.
The operation produces wastewater with chemical oxygen demand concentrations (COD) of approximately 8,700 mg/l and elevated nitrogen concentrations of about 640 mg/l. The customer’s objective is to reuse the treated wastewater and to recover the organic constituents and nitrogen for resale. To achieve this goal, COD level in the treated water has to be reduced below 150 mg/l, and the organic constituents and nitrogen have to be concentrated by a factor of about 4x or above in the reject stream.