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PubMed · 17161445

Ammonium removal from digested sludge liquors using ion exchange.

A Thornton·P Pearce·S A Parsons
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Abstract

Liquors arising from the dewatering of digested sludge typically contain ammonium levels in the range 200-700mgl(-1) NH(4)(+)-N. These liquors are frequently recycled to the head of the wastewater treatment works (WwTW) untreated and can constitute >25% of the total nitrogen load entering the works at inlet. This paper investigates the use of a clay-based material, MesoLite, as an ion exchange medium for ammonium removal from recycle streams. Pilot-scale studies performed at Didcot WwTW, part of the Thames Water wastewater treatment network, indicate that MesoLite is highly selective for the ammonium ion. Results show that >95% of ammonium was removed from belt press liquors with an initial ammonium nitrogen concentration >600mgl(-1), with an overall ion exchange capacity >51g NH(4)(+)-Nkg(-1) medium and this resulted in an operating capacity in the range 27-36gNH(4)(+)-Nkg(-1).

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Aluminum SilicatesBioreactorsClayIon ExchangePilot ProjectsQuaternary Ammonium CompoundsSewageWaste Disposal, FluidWater PurificationJournal ArticleResearch Support, Non-U.S. Gov't

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A Thornton, P Pearce, S A Parsons. 2006-12-11. Ammonium removal from digested sludge liquors using ion exchange.. https://doi.org/10.1016/j.watres.2006.10.021

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