Ammonium removal from wastewaters using natural New Zealand zeolites

Abstract

Ammoniacal nitrogen (ammonia and ammonium) in agricultural wastewaters can promote eutrophication of receiving waters and be potentially toxic to fish and other aquatic life. Zeolites, which are hydrated aluminum-silicate minerals, have an affinity for ammonium ions (NH 4 + ) and are, therefore, potentially useful in removing this contaminant from wastewaters. The major objectives of this study were to evaluate the capacity of two natural New Zealand zeolites (clinoptilolite and mordenite) to remove NH 4 + from a range of wastewaters under both batch and flowthrough conditions. Effects of two zeolite particle size ranges (0.25-0.50 mm and 2.0-2.83 mm) on NH 4 + removal performance were also investigated. Results obtained from the batch adsorption experiments indicated that both zeolites tested, regardless of their particle sizes, were equally effective (87-98%) -3 of wastewater throughput, which equates up to 5.8-6.5 g NH 4 -N kg -1 zeolite. In contrast, at a faster loading flow rate (15.9 mm min -1 ), the breakthrough was almost immediate (1 BV) for coarse zeolites and after 22 BVs for fine zeolite. The NH 4 + breakthrough capacity for fine mordenite was 2.0-4.4 g NH 4 -N kg -1 zeolite. Fine zeolites were more effective than coarse zeolites in removing wastewater NH 4 + (95% and 55% removal, respectively), even after receiving 64 BV of wastewater.

Influence of natural zeolite on nitrogen dynamics in soil

“…When nutrients are introduced into the soil in this way, their consumption is reduced, so there is no need for redundant delivery of raw materials and consequently fewer nutrients (mostly nitrogen, which causes eutrophication of water sources) are leached into ground and surface waters. Zeolites from Italy (Ciambelli et al, 1985) and New Zealand (Nguyen and Tanner, 1998) have been used for ammonium removal from wastewater. After researching Turkish zeolites, Işıldar (1999) confirmed that nitrification decreased after zeolite application to soil, albeit not in all observed soil types.…”

Hydroponic systems and water management in aquaponics: a review

“…Furthermore, zeolite reduced the concentrations of inorganic N (-36.5%) and P (-17.9%) in the system water. Zeolites are characterised by high cation-exchange capabilities, and are thus able to adsorb ammonium-N (Nguyen and Tanner, 1998;Wang and Peng, 2010;Borin et al, 2013;Markou et al, 2014). In addition, iron-and aluminiumbased crystalline and amorphous phases can become positively charged and, through a ligand exchange mechanism, their adsorption capabilities increase at neutral to acidic equilibrium pH values in comparison to alkaline conditions (Parfitt, 1979;Geelhoed et al, 1997).…”

Applicability of Natural Zeolite for NH-Forms Removal in Enzyme-Mediated Calcite Precipitation Technique

“…Natural zeolite has a unique structure, large internal cavities, and entry channels [17]. It is proved to have high cation exchange capacity, cation selectivity, higher void volume, and a great affinity for ammonium (NH 4 + ) and other cations [18,[27][28][29]. It is also low in cost and independent of temperature [18,19,22,27].…”