Research On Cation Competition Of The Process Removing Ammonium With High-efficient Ammonium Ion-sieve And Sieve Molding

In municipal wastewater, nitrogen above 90% especially the one after secondary treatment usually exists in form of ammonium. Removal of nitrogen in form of ammonium is easier and more economical than nitrate. Sometimes we do not need to remove the total nitrogen but ammonium. Ammonium in landscape water may cause algae propagate rapidly, thus it can debase the water quality. Using of ammonium in the sterilization of industry circular water may cause more chorline's consumption.Ammonium also erode metals especially cuprum. We should take that in to consideration. In case of this, it is important to remove ammonium when the reused water is used in landscape water or industry circular water system.This paper selects three kinds of cation which is Na⁺, Mg²⁺ and Ca²⁺ in the reused water as delegate. We study the character of cation's competition and adsorption with ammonium in the process removing ammonium using high-efficient ammonium ion-sieve. We select the appropriate experiment's condition and establish the ion competition and adsorption dynamics model. The results show that Na+ and Mg²⁺ have little effect on the adsorption capacity of the NH+4⁺ while Ca²⁺ affects it dramatically. The ion-sieve shows better selectivity of Ca²⁺.This paper also study the method and condition of ammonium ion-sieve's molding. Comparing with many kinds of molding's methods, we finally fix on extrusion molding method. We add proper proportion of reagent in to powder, mix and squeeze. After baking we could get ion-sieve in the form of granule. On the base of that, we test and token the molding granule. We use the electronic multifunctional machine to test the granule's intensity and use XRD to analyze the granule's structure. The results show that the structure of the granule hasn't been changed, which indicate the molding doesn't destroy the granule's structure and won't affect its adsorption capacity. We also study the granule's surface using SEM. The SEM results show that the surface of granule forms a lot of pores with similar size which is propitious to solid and liquid's contact. This will enhance the reactive efficiency of ion's exchange.