Start-up of a nitrification system with automatic control to treat highly concentrated ammonium wastewater: Experimental results and modeling

The Start-Up of Aerated Submerged Fixed-Bed Biofilm Reactors for Steady State Nitrification

“…The results show that the gradual increase of NLR was not significant in shortening the start-up period for a medium-strength ammonium wastewater (NH4 + -N ~ 65 mg l -1 ). This in contrast to studies conducted for highstrength ammonium wastewaters (Jubany et al, 2008).…”

“…However, there have not been any studies on the effectiveness of such procedures for mediumstrength ammonium wastewater (where the NH4 + -N content ranges from 50 to 100 mg l -1 ) in SFBBRs carrying out the nitrification process. Researchers have reported that these reactors take long periods of up to several months just to reach steady state (for example Jubany et al, 2008). However, the length of this period seems to vary based on the different operation conditions that were selected for start-up, as well as the specifics of the treatment processes.…”

“…Free ammonia (FA) and free nitrous acid (FNA) can inhibit the growth of nitrifying bacteria during the start-up (Philips et al, 2002). For highstrength ammonium wastewater, when the nitrogen-loading rate (NLR) is greater than the maximum nitrification rate, it is now widely agreed that start-up of the process should be carried out with a stepwise and controlled increase of the NLR (Jubany et al, 2008). However, there have not been any studies on the effectiveness of such procedures for mediumstrength ammonium wastewater (where the NH4 + -N content ranges from 50 to 100 mg l -1 ) in SFBBRs carrying out the nitrification process.…”

High-throughput nitritation of reject water with a novel ammonium control loop: Stable effluent generation for anammox or heterotrophic denitritation

“…An extended description and justification of both kinetic models and parameters can be found elsewhere [15]. The kinetic parameters for AOB and NOB populations were adequately modified to the temperature and pH used in this study according to the equations described in [24]. FA and FNA concentrations were calculated from the measured TAN and TNN concentrations using the acid-base equilibria (equations 5 and 6) [25].…”

A novel control strategy for enhancing biological N-removal in a granular sequencing batch reactor: A model-based study

“…To overcome these limitations, two modifications were introduced: (i) the model considered simultaneous growth and storage of organic matter by heterotrophic bacteria as described by Sin et al [31], (ii) nitrite was included as nitrification intermediate as described by Jubany et al [32], since there was an evident accumulation of nitrite in the GSBR (Fig. 1).…”