Full-scale partial nitritation/anammox experiences – An application survey

Abstract

Partial nitritation/anammox (PN/A) has been one of the most innovative developments in biological wastewater treatment in recent years. With its discovery in the 1990s a completely new way of ammonium removal from wastewater became available. Over the past decade many technologies have been developed and studied for their applicability to the PN/A concept and several have made it into full-scale. With the perspective of reaching 100 full-scale installations in operation worldwide by 2014 this work presents a summary of PN/A technologies that have been successfully developed, implemented and optimized for high-strength ammonium wastewaters with low C:N ratios and elevated temperatures. The data revealed that more than 50% of all PN/A installations are sequencing batch reactors, 88% of all plants being operated as single-stage systems, and 75% for sidestream treatment of municipal wastewater. Additionally an in-depth survey of 14 full-scale installations was conducted to evaluate practical experiences and report on operational control and troubleshooting. Incoming solids, aeration control and nitrate built up were revealed as the main operational difficulties. The information provided gives a unique/new perspective throughout all the major technologies and discusses the remaining obstacles.

One-stage deammonification start-up control using ion-selective electrodes (ISE) sensor

“…Robust deammonification in cold streams with low ammonium concentration, such as municipal wastewater (mainstream treatment), is still subject of intense research and should be considered as an infancy stage so far [3][4][5][6]. Until 2014, there was over 100 full-scale side-stream installations, where 88% of them was in one-stage reactor configuration, which means that partial nitritation and Anammox (PN/Anammox) processes occur in a single reactor [7].…”

Shortcut nitrification/partial nitritation start-up for reject water treatment in a SBR

“…Rising popularity of this process can be proven by over 100 PN/Anammox installations operating worldwide by 2014 [6].…”

Manometric measurements of temperature influence on Anammox activity

“…In engineering practice anammox process becomes more commonly applied as wastewater treatment plants face more stringent effluent limits, especially with regard to total nitrogen, which force them to consider sidestream nitrogen removal from digested sludge dewatering liquor which can contain up to 20% of incoming nitrogen load [3].…”

“…As raw reject water contains mainly ammonium, the partial nitrification step, conducted by strictly aerobic ammonium oxidizing bacteria, is required to oxidize approximately half of the initial ammonium to nitrite. In the anammox step ammonium (electron donor) and nitrite (electron acceptor) are converted by strictly anaerobic anammox bacteria into dinitrogen gas and small amounts (~10%) of nitrate without external organic carbon source, according to equation [3,5] …”

“…The advantage of deammonification is that it allows to decrease oxygen demand by 60%, and organic carbon demand and sludge production by 90%, compared to conventional nitrification/denitrification systems [1,3,5].…”