When Methanol Addition is Cheaper than Free Wastewater for Denitrification

A systematic evaluation of estimated construction and operation costs shows that the use of methanol at the Smithfield Packing Plant near Tar Heel, NC is a more economical carbon source for denitrification than anaerobic lagoon influent. The capital and O&M cost comparison of the two options shows that the methanol addition results in a yearly savings of 317,750 when compared to the anaerobic by-pass option. This difference is primarily due to:Lower estimated capital costs due to the High-Strength Equalization Basin required with the by-pass option.Reduced biogas production in the anaerobic lagoon associated with the by-pass option.Reduced aeration requirements and solids handling costs associated with the methanol addition.This evaluation illustrates the importance of all operational considerations when selecting a carbon source for denitrification at an industrial facility.