Model based design of a novel process for nitrogen removal from concentrated flows

A new process for biological nitrification was developed that is operated i n a single aerated reactor at relatively high temperature and pH. This proc ess, termed SHARON, was designed to achieve substantial ammonia conversion at high reaction rates for relatively concentrated flows, rather than to me et strict effluent standards. First large scale applications that are under construction now, aim at treating reject water from a sludge digestion uni t. The SHARON process operates without sludge retention, and ammonium oxida tion is stopped at nitrite, which saves on aeration costs. Denitrification is used as a cheap means to control the pH. Under typical conditions, no he ating is necessary due to the heat production by the reactions. Overall pro cessing costs are less than 50% of other techniques. This contribution focu ses on model development for process design calculations at full scale. Und erlying kinetic principles, and especially their pH dependency, are highlig hted as well.