Chemical Precipitation of Ammonia and Phosphate from Nam Son Landfill Leachate, Hanoi

Abstract

Abstract:Leachate from municipal landfills of the city is often contaminated heavily, especially for parameters such as organic components, heavy metals, microorganisms. However, leachate also contains amounts of valuable nutrients (e.g. N, P, K) which can be used for agriculture as fertilizers. Precipitated of N and P in the form of struvite (MgNH 4 PO 4 .6H 2 O) might be applied as a technique for removal a huge amount of N as well as P in wastewater. This study investigated the recovery ability of N, P in leachate from Nam Son municipal landfill of Hanoi city. Different pH values, anaerobic time and stoichiometric Mg 2+ : NH 4 + : PO 4 3-was tested to determine the optimal conditions for precipitating struvite. The effect of pH on the forming of struvite was between pH 9 to 11. The results showed that nutrients in landfill leachate could be recovered with the optimum pH around 9.5 and the optimum Mg 2+ : NH 4 + : PO 4 3-molar ratio as 1.15: 1: 1. With the anaerobic interval of 21 days, COD value in landfill leachate was decreased to 60%, the retrieval reached 80.6% for nitrogen and 82.7% for phosphorus. According to estimates, with the application of struvite precipitation technique, the average annual retrieval amount of NH 4 + and PO 4 3-can reach 263 tons and 25 tons, respectively.

Phytoaccumulation of heavy metals from municipal solid waste leachate using different grasses under hydroponic condition

“…The average concentration of COD before treatment was calculated 5163.6 and reduced to 1715.2 mg/L after treatment which showed a reduction of 66.8% of COD. Similar outcome has been reported earlier 5,13 which were 61 and 63.11% respectively. In a hydroponic experiments, investigated 24,25 showed that vetiver grass has the ability to survive in leachate with COD of 750 mg/L to 2600 mg/L and this research showed that vetiver grass could still survive in the 100% leachate strength in which the COD value was 6930, which is a high COD value.…”

“…If the leachate goes unattended by percolation into subsoil layers, it can deteriorate the underlying soil and groundwater 4 . The quantity and quality of leachate depends upon the source of water entering into the dumpsite 5 .…”

Effect of some effective parameters on COD Removal from Nam Son Landfill Leachate by electrocoagulation

“…This landfill with area of 83.5 hectares has started mechanized operation in 1999 and expanded to 112 hectares in 2015. Currently, Nam Son landfill receives about 4300 to 4500 tons of waste per day and approximately 2000 m 3 leachate, yet only 1500 m 3 leachate is treated daily [5].…”

Penurunan Kadar Amonium dan Fosfat pada Limbah Cair Industri Pupuk

“…Selain itu struvite menjadi sumber N, Mg 2+ , dan P yang sangat efektif untuk tanaman dan dapat digunakan sebagai pupuk slow release tanpa merusak akar tanaman [5;6]. Presipitasi struvite dipengaruhi oleh beberapa faktor, diantaranya pH, komposisi kimia air limbah (derajat kejenuhan terhadap magnesium, amonium dan fosfat; kehadiran ion lainnya; kekuatan ion) dan suhu larutan [7]. Faktor yang paling berpengaruh pada presipitasi struvite adalah rasio molar Mg 2+ : NH4 + :PO4 3dan pH [8] Presipitat hasil presipitasi optimum akan dianalisis morfologi dan strukturnya menggunakan SEM-EDX.…”