The researchers experimented with recirculating leachate in solid waste cells to speed up the breakdown of organic waste. By adding nutrients and sludge to the leachate, they found that the biological degradation process was accelerated. This led to a quicker decrease in organic waste and an increase in methane production. The addition of nutrients and buffer solutions also boosted microbial activity in the waste cells. Overall, the study showed that enhancing biological degradation in landfills can have several benefits, including faster waste breakdown and increased methane production.