The leachate from municipal waste landfill in Korea, is partially treated only to remove organics in the Conventional Leachate Treatment Plant. But it is necessary to remove nutrients from the leachate in the landfill site to keep up with new regulation established on 1996.
Several processes have been developed to remove nutrients from leachate such as CSTR(Continuous Stirred Tank Reactor), UBF(Upflow Bed Filter), Membrane Separation (MF, UF, NF, R/O), Photocatalytic Oxidation (UV/H₂, O₂, UV/O₃, EB) and B3 system(Bacillus sp. process).
However, it has been often noted operational troubles in the above plants owing to high concentration of ammonia and non-biodegradable matters of leachate.
In this study, a Plot scale experiment was conducted for 1 year to evaluate the applicability and several factors in treating leachate with bacillus sp. style biological treatment process, which recently developed in Korea.
The results of experiments can be summarized as follows :
(1) If enough reaction time and organic matter are given, nitrification and denitrification happened at the same time in reactor.
(2) The pH and alkalinity was increased and the removal of nitrate was decreased in accordance with increasing the concentration of ammonia. The pH range occurred nitrification was between 6.3 to 8.7.
(3) When the concentration of NH₄^+-N is more than 3000ppm, the growth of bacillus sp. was stopped.
(4) When the inflow concentration of ammonia was extremely high, it was confirmed to be needed pretreatment process, such as pH of flow control.