Improving Anaerobic Digestion of Cheese Whey for Increasing the Biochemical Methane Potential

The best conditions for anaerobic digestion of cheese whey (CW) to obtain the maximum biochemical methane potential (BMP) were carried out in two stages. In the first stage, using a composite central experimental design, substrate concentration, inoculum concentration, and pH were optimized in order to find the maximum BMP values. In the second stage, the effect of adding nitrogen as urea, ammonium sulfate, and ammonium nitrate was evaluated. In the first stage, the maximum BMP of 469.75 ± 3.25 mL CH 4 /g VS was obtained at a CW concentration of 24.6 g/L, inoculum concentration of 22.4 g/L, and pH of 7.1. In the second stage with urea supplementation at a concentration of 1,000 mg/L, BMP increased by 9.4%, obtaining values of 513.95 ± 2.12 mL CH 4 /g VS. The findings contribute to improving the production of methane from the anaerobic digestion of CW, with the expectation of implementing the data obtained in a biodigester.