Landfill Leachate as an Abundant Source of Nitrogen: Case Study Using a Submerged Aerated Filter under Nonalkalinization Condition

This study presents the performance of submerged aerated filter technology in removing ammonia from landfill leachate. The investigation proposes the filter without the use of chemical agents to alter the pH. The research was developed in real scale. The efficiencies obtained, for a hydraulic retention time of 56 days, were as follows: 83% removal of ammoniacal nitrogen (influent concentration of 2,653 mg/L) and 78% removal of total Kjeldahl nitrogen (influent of 3,058 mg/L). The pH variation range was from 8.3 to 9.3. The alkalinity showed a reduction from 12,338 to 4,015 mg/L. The dissolved oxygen concentration ranged from 0 to 8.3 mg/L. The research hypothesis was positively confirmed: there is no need to alkalinize the medium to obtain high ammonia removal in the leachate; in terms of load, this expulsion was quite significant: 2.6 t. This result establishes leachate as an abundant source for obtaining the chemical element nitrogen, which is so necessary as a macronutrient for the fertilizer industry and food production.