文摘
Society needs sustainable methods for landfilling from an environmental perspective, but they have to be cost effective and affordable. Aftercare represents considerable costs within waste management system and costs can be expected to accrue over a long period of time showing the need to compare different management options. Direct-discharge limits for leachate COD and nitrogen are different in various (European) countries. When leachate COD or nitrogen has decreased at the latter part of the aftercare period, effluent limits 50 or 200 mg/l for COD and 10 or 70 mg/l for nitrogen have a considerable impact on period length. The objective of this paper is to discuss the effects of leachate discharge limits on landfill aftercare and leachate management costs in various conditions. Landfill simulator results and modelling are used to estimate leachate concentrations in three different scenarios. It is suggested that stricter discharge limits (shown before) impact on the costs of activated carbon filtration (1.4-fold) and biological treatment (1.1–1.24-fold). Stricter limits also extend the aftercare period length considerably, but with substantial water circulation the differences are clearly smaller. These results support the recent suggestion of aftercare incentives, and some details of applying these incentives in different conditions are discussed.