| Operation of waste cells as bioreactors is an attractive option for managing municipal solid waste. Among various techniques, leachate recirculation is one of the most promising techniques for accelerating waste degradation in landfill bioreactors. Although leachate recirculation has been practised in some landfills worldwide, leachate augmentation with enzymes, prior to its recirculation, to enhance the waste degradation and gas production in anaerobic landfill bioreactors is a relatively new concept, and little is known about its applicability. This research was undertaken to determine the viability of enzymatic augmentation of leachate with peroxidase enzymes to enhance the waste degradation rates at later stages of anaerobic bioreactor operation. A comprehensive set of laboratory experiments were conducted to assess the viability of this process and to identify the process parameters. The results showed that there was a significant increase in the cumulative methane production in enzyme-added batch reactors and flow-through columns compared to the corresponding control operation. This observation is attributed to an increase in the fraction of waste being degraded as indicated by the increasing levels of dissolved organic carbon and decreased lignin levels in the waste. |
