Ammonia removal from landfill leachate by air stripping and absorption

Abstract

An old landfill leachate was pre-treated in a pilot-scale aerated packed tower operated in batch mode for total ammoniacal nitrogen (TAN) removal. The stripped ammonia was recovered with a 0.4 mol L(-1) H2SO4 solution, deionized water and tap water. Ca(OH)2 (95% purity) or commercial hydrated lime was added to the raw leachate to adjust its pH to 11, causing removal of colour (82%) and heavy metals (70-90% for Zn, Fe and Mn). The 0.4 molL(-1) H2SO4 solution was able to neutralize 80% of the stripped ammonia removed from 12 L of leachate. The effectiveness of the neutralization of ammonia with deionized water was 75%. Treating 100 L of leachate, the air stripping tower removed 88% of TAN after 72 h of aeration, and 87% of the stripped ammonia was recovered in two 31 L pilot-scale absorption units filled with 20 L of tap water.

Removal of ammonium from municipal landfill leachate using natural zeolites

“…Leachate generated from landfill sites is characterized with high concentrations of organic matter, inorganic salts, heavy metals and ammonium-nitrogen. [1][2][3] The discharging of leachate may pose a great threat to the environment. Among the leachate constituents, ammonium is the most significant pollutant in the long term, and its concentration can be found up to several thousand mg/L.…”

“…Among the leachate constituents, ammonium is the most significant pollutant in the long term, and its concentration can be found up to several thousand mg/L. [1,3] The release of high level of ammonium without proper treatment decreases the performance of conventional biological treatment systems and accelerates eutrophication, dissolved oxygen depletion and toxicity of living organisms in surface waters. [4] Therefore, the removal of high ammonium concentration from leachate has become a critical issue in recent years.…”

“…[4] Therefore, the removal of high ammonium concentration from leachate has become a critical issue in recent years. Various treatment technologies have been applied to remove ammonium from leachate, such as biological processes, [5,6] electro-oxidation, [7,8] air stripping, [3,4] chemical precipitation, [9,10] adsorption and ion exchange. [1,11] Among these treatment methods, ion exchange using zeolites is very attractive due to its low cost and relatively simple application.…”

Removal of ammonia from a smelting wastewater by cyclic stripping and acid adsorption: Kinetics study

“…Reference pH T ( C) F 1 (m 3 Áh −1 ) C 0 (mgÁL −1 ) C t (mgÁL −1 ) t (h) G (h −1 ) This test 12 .2 25 30 5951 13 15 0.435 [15] 11.0 25 4.5 830 10 20 0.180 [16] 11.0 50 ---24 0.160 [17] 12.0 20 2.69 1964 44 19 0.200 [18] 11.0 50 70 1243 198 24 0.077 [19] 11.0 -0.9 1350 150 18 0.122 Figure 9. Parity graph for the predicted values of the overall ammonia removal rate by the proposed semiempirical model in the cyclic stripping process.…”

Experimental plant for the physical-chemical treatment of groundwater polluted by Municipal Solid Waste (MSW) leachate, with ammonia recovery

“…Particular mention must be made of the stripping process, which involves several applications in full-scale plants, even if most of them are based on rudimentary techniques, in order to carry out even simple leachate pretreatments. Only in a few cases, the stripping process is the option for achieving a high ammonia removal efficiency and subsequent recovery (Kabdasli et al, 2000;Campos et al, 2013;Ferraz et al, 2013).…”