Effect of Food Waste Diversion on Leachate Quality

Investigator: North Carolina State University

Start Date:
March 2017

Award Amount:
$75,000

Approximately 19,500 million gallons of leachate was estimated to have been sent to a wastewater treatment plant (WWTP) in the U.S. in 2013. Landfill leachate increasingly requires pre-treatment because it contains high levels of refractory organic matter (ROM) and ammonia that could impact WWTP operations. ROM (i.e. humic- and fulvic-like substances) in leachate reduces the effectiveness of UV disinfection. As a result, WWTPs increasingly refuse to accept landfill leachate, pressuring landfill owners to explore costlier treatment alternatives.

Thus, understanding the sources of ROM and exploration of alternatives to reduce its presence in leachates are needed. Concurrent with the difficulty in treating leachate in WWTPs, the diversion of food waste from landfills is increasing. This diversion is motivated by several factors including responses to policies banning food waste disposal, reducing landfill methane emissions, and more efficient recovery and utilization of methane from anaerobic digesters. As the composition of the waste stream changes, changes to leachate quality can be expected.

The objectives of the study are:

  1. To determine the effect of removing food waste from municipal solid waste (MSW) on leachate quality during waste decomposition under simulated landfill conditions
  2. To characterize the compounds/moieties that absorb UV at 254 nm in samples of leachate produced in systems with and without food waste

It is hypothesized that food waste diversion will result in reduced ammonia and ROM since food waste is readily degradable and more easily solubilized, when compared to other MSW organics.