G. Dimova et al., Combined filter for ammonia removal - Part I: Minimal zeolite contact timeand requirements for desorption, WATER SCI T, 39(8), 1999, pp. 123-129
The minimal contact time in removal of ammonia ions by ion-exchange with ze
olite, Na-form, is determined using the method of differential element. The
relationship between the contact time, the water velocity, the effect of r
emoval and the initial ammonia concentration is investigated. The obtained
data serve as a basis for mathematical modeling of the ion exchange kinetic
s and give valuable information about some design parameters of ion-exchang
e facilities. Some basic analyses, concerning the desorption of ammonia fro
m zeolite, induced mainly from the cations naturally present in surface wat
ers ate made. The influence of water velocity and water hardness on such de
sorption is investigated, These experimental data and analyses are an essen
tial part of a study, the purpose of which is to investigate the possibilit
ies for ammonia removal and biological regeneration of zeolite in a combine
d facility, using the processes: ion-exchange, desorption induced by small
concentrations of cations and biological nitrification. (C) 1999 Published
by Elsevier Science Ltd on behalf of the IAWQ. All rights reserved.