MBBR Process Proves Highly Effective for Treating Variable Strength Landfill Leachate

摘要

Seneca Landfill, in Mars, PA, has recently retrofitted their treatment train to include a series ofthree moving bed biological reactors (MBBRs), to maximize the onsite treatment of ammonia.The wastewater influent stream is composed of landfill leachate, as well as of condensate fromtheir methane recovery system. The goal of treatment is to obtain effluent ammoniaconcentrations of less than 4.7 mg/L at as high a flow rate as possible. The influent ammoniaconcentration averages over 1,000 mg/L, and spikes higher than 3,000 mg/L. Before the upgradebegan, the landfill was not able to consistently treat its leachate to below the effluent limit, andso virtually all of the landfill leachate needed to be treated off-site.Today, the landfill is able to consistently treat 20 gpm (28,000 gpd) of waste at typical ammonialoading rates, and therefore allowed to discharge the waste into the municipal sewer system.There are still occasions when there is too much ammonia coming into the treatment system tobe treated, in which case the effluent is redirected back to the equalization tanks for furthertreatment. The current objective is to continue to optimize the current configuration in order toincrease the capacity of the existing system.Due to the step-by-step nature of this upgrade, in which both the bio-towers and the hydraulicswere upgraded over the course of 6 months, it was possible to collect data at a variety ofdifferent reactor configurations. Four of these arrangements are examined in this paper, and thepercent of influent ammonia treated as well as the pounds of ammonia removed per cubic meterof media are examined for each case. The dates of the study were from September 2011 throughJune 2012.