Performance and kinetics of ANAMMOX granular sludge with pH shock in a sequencing batch reactor

Abstract

As an efficient and cost-effective nitrogen removal process, anaerobic ammonium oxidation (ANAMMOX) could be well operated at suitable pH condition. However, pH shock occurred in different kinds of wastewater and affected ANANNOX process greatly. The present research aimed at studying the performance and kinetics of ANAMMOX granular sludge with pH shock. When influent pH was below 7.5, effluent NH -N deviated from theoretical value. Longer recovery time from pH 9.0 than from pH 6.0 indicated that alkaline surroundings inhibited anaerobic ammonium oxidizing bacteria (AAOB) greater. The sludge settling velocity was 2.15 cm/s at pH 7.5. However, it decreased to 2.02 cm/s when pH was 9.0. Acidic pH had little effect on sludge size, but disintegration of ANA-MMOX granule was achieved with pH of 9.0. The Bell-shaped (A) model and the Ratkowsky model were more applicable to simulate the effect resulting from pH shock on ANAMMOX activity (R 2 [ 0.95), and both could describe ANAMMOX activity well with pH shock. They indicated that q max was 0.37 kg DNH þ 4 -N/(kgMLSSÁd) at the optimum pH value (7.47) in present study. The minimum pH during which ANAMMOX occurred was 5.68 while the maximum pH for ANAMMOX reaction was 9.26. Based on nitrogen removal performance with different pH, strongly acidic (pH B 6.5) or alkaline (pH C 8.5) inhibited ANAMMOX process. Besides, ANA-MMOX appeared to be more susceptible to alkaline wastewater. Compared to extremely acidic condition (low pH), extremely alkaline condition (high pH) affected ANAMMOX granules much more.Electronic supplementary material The online version of this article

Enhanced carbon and nitrogen removal performance of simultaneous anammox and denitrification (SAD) with mannitol addition treating saline wastewater

“…The high value of R 2 (0.9635, 0.9857, 0.9815) from the three models dictated a good linear relationship between the experimental data and the predicted value. The t‐value (0.06, 2.54E‐06, 2.56E‐05) were much lower than the value of t crit (0.703) indicating that the models were unbiased . These findings demonstrated that all three models could be suitably applied for determining the TNRE with the addition of mannitol in a SAD process.…”

“…The t-value (0.06, 2.54E-06, 2.56E-05) were much lower than the value of t crit (0.703) indicating that the models were unbiased. [43][44][45] These findings demonstrated that all three models could be suitably applied for determining the TNRE with the addition of mannitol in a SAD process. The kinetic analysis for high mannitol inhibition recovery period is shown in Figs S4 and S2.…”

Response and Adaptation of Microbial Community in a CANON Reactor Exposed to an Extreme Alkaline Shock

“…Thus, the CANON process was severely inhibited by the alkaline shock. As Li et al [ 11 ] reported, the effect of an alkaline pH (9.0) shock on the performance of anammox granular sludge was much more severe than that of an acidic pH (6.5) shock, and the alkaline condition disintegrated anammox granules. Based on the impact of influent pH of 4 and 10 for 12 h, Yu and Jin [ 35 ] also found a loss of anammox performance only in alkaline condition.…”

“…Fux et al [ 10 ] pointed out that specific anammox activity (SAA) of anammox was completely inhibited by pH 9.3. Li et al [ 11 ] observed the disintegration of anammox granule at pH 9.0. When the concentration of FA reaches approximately 32.5 mg·L −1 at pH 8.5, anammox bacteria and ammonia oxidising bacteria (AOB) activities are severely inhibited, and the performance of the CANON system deteriorates quickly [ 9 ].…”

Anammox and partial denitrification coupling: a review

“…If the amount of alkali production is uncertain, slightly alkaline inlet water is more suitable. 110,111 It is suitable for slightly alkaline inlet water.…”