Optimization of Food Waste Bioevaporation Process Using Response Surface Methodology

Abstract

A proven bioevaporation process was used to treat food waste (FW) by mixing ground FW with biodried sludge (BS). Organic loading (OL), moisture content (MC), and air flow rate (Q_g) showed significant influences on FW bioevaporation performance. Single-parameter experiments for MC and Q_g were conducted and ranges were determined to be 55–67 wt% and 0.04–0.14 m³/kg TS_mixture · h, respectively. In order to optimize the FW bioevaporation process, a central composite design (CCD) and response surface method (RSM) were applied over the preselected ranges of OL (0.00–0.16 kg VS_FW/kg TS_BS), MC (50.91–71.09 wt%), and Q_g (0.01–0.17 m³/kg TS_mixture · h). The results indicated that OL of 0.06 kg VS_FW/kg TS_BS, MC of 59.2 wt%, and Q_g of 0.09 m³/kg TS_mixture · h were the optimal conditions for the FW bioevaporation process. Water evaporation of 123.1% and VS degradation of 108.4% were obtained under these estimated optimal conditions.

Keywords:

• Bioevaporation
• Food waste
• Optimization
• Response surface methodology