Silage treatment using constructed wetlands

A growing concern for small dairy farmers in Western Massachusetts is the management of silage leachate. Silage leachate is a toxic organic liquid that is produced in dairy farms during the fermentation process of corn. A senior honors thesis work began to explore the possibility of using constructed wetlands to treat silage leachate. There are several design options that have been studied in this project and the one that best fits the criteria of nutrient removal and Biochemical Oxygen Demand reduction has been analyzed. All the design suggestions made have been based on analysis of previous case studies of constructed wetlands used to treat waste water. The recommended design that would be best suited to leachate treatment is a hybrid vertical and horizontal flow type constructed wetland. It has bulrush as vegetation and gravel and sand as substrates with a treatment area of 52m2. The recommended design should have to capacity to reduce nutrients and BOD with an efficiency of as high as 80%. Comparison of the final design of constructed wetland with the filtration system suggested by the Smith College Design Clinic Team Razcas (2013-2014) showed that the constructed wetland would be a more effective but costly and time intensive option. Thus, only farmers willing to invest resources into a constructed wetland would benefit from this venture in the long term.