A waste management model for optimal recycling–landfilling policies under macroeconomic conditions

This research provides a waste management model in the presence of macroeconomic conditions. An optimal control problem which integrates the recycling–landfilling decision with industry supply–demand dynamics is designed to achieve the value-maximizing objective. The model simultaneously considers idiosyncratic technical and aggregate demand shocks, while the stoppage time for landfill use is assumed to follow a Cox process with the intensity function of a firm's total waste collection. The closed-form solution of the optimal recycling ratio is also derived. The results suggest that when macroeconomic effects are neglected, optimal recycling ratios tend to be underestimated.