Prioritization of suitable sludge treatment and management methods is a complex task that requires the assessment of alternatives across usually conflicting criteria. In this paper, four possible methods (compositing, anaerobic digestion, incineration, and alkaline stabilization) applicable in sludge treatment and management in Metro Manila, Philippines, were evaluated. The analytic hierarchy process (AHP) was then used in ranking the alternatives in terms of technical, environmental, and economic considerations. Results illustrated that compositing is the most preferred alternative, followed by alkaline stabilization, anaerobic digestion, and incineration. To explore the robustness of the decision modeling results, a sensitivity analysis was performed.
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