Showing papers on "Enhanced biological phosphorus removal published in 2020"
TL;DR: Analysis of key enzyme activities indicated that the presence of DCF reduced the activities of exopolyphosphatase and polyphosphate kinase, which revealed that DCF promoted the ratio of protein to polysaccharide in activated sludge extracellular polymers and inhibited anaerobic phosphorus release and oxic phosphorus uptake.
77 citations
TL;DR: Results deciphered the resilience of aerobic granular sludge-based biological nitrogen and phosphorus removal processes to hypersaline stress and revealed multiple halophilic and non-halophilic bacteria within aerobic granules with family Anaerolineaceae being the predominant potential salt adapter.
73 citations
TL;DR: Enhanced biological phosphorus removal (EBPR) in practical wastewater treatment via improving identification of bacterial species and symbiosis of bacteria community is explored via improvingIdentification of phosphate-accumulating organisms (PAOs), denitrification and accumulating phosphorous though RDA and chord plot.
59 citations
TL;DR: Results showed that about 86% of influent phosphorus could be removed within 6 h comprising 2-hr dark phase and 4-hr light phase, and the removal mechanisms of phosphorus by microalgal-bacterial granular sludge process were identified.
52 citations
TL;DR: This work presents the long term operation of a demo-scale pilot plant with a novel configuration named as mainstream SCEPPHAR (ShortCut Enhanced Phosphorus and polyhydroxyalkanoate (PHA) Recovery) based on two sequencing batch reactors.
46 citations
TL;DR: It appears from this this study that the micro-ferrous dosing strategy is practically feasible and economically viable for enhanced phosphorus removal from municipal wastewater.
43 citations
TL;DR: This work shows that functioning of aerobic granular sludge in seawater conditions is as stable as in freshwater conditions, while past research has shown a negative effect on operation of AGS processes with NaCl-based wastewater at the same salinity as seawater.
39 citations
TL;DR: In this article, a comprehensive literature analysis evaluated essential partial nitrification (PN) parameters including various reactor configurations, control strategies on dissolved oxygen (DO) and aeration, pH, inhibition via free ammonia (FA) and free-nitrous acid (FNA), and oxidation reduction potential (ORP) in both pilot and full-scale systems.
Abstract: This comprehensive literature analysis evaluated essential partial nitrification (PN) parameters including various reactor configurations, control strategies on dissolved oxygen (DO) and aeration, pH, inhibition via free ammonia (FA) and free-nitrous acid (FNA), and oxidation reduction potential (ORP) in both pilot and full-scale systems. The median growth rates for ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) at 20 °C are 0.74 and 0.65 d−1, respectively. The median first-order decay coefficient for both AOB and NOB was 0.14 d−1 while the average biomass yields were 0.17 and 0.08 mg chemical oxygen demand (COD) mg N−1. The COD/N ratio is one of the critical factors for partial nitrification, particularly for attached growth systems. The optimum COD/N ratio for partial nitrification appears to be system-specific, as it is impacted both by system design parameters and operational conditions. The most widely used PN technology is the sequencing batch reactor (SBR) despite significantly lower volumetric nitrogen loading rates due to the ease of NOB suppression by the relatively high FA and FNA concentrations during the early stage of aeration. This review identified several knowledge gaps including better understanding of PN mechanisms in attached growth systems, combination of PN and enhanced biological phosphorous removal (EBPR), and development of process control strategies for technologies other than SBRs. Mainstream low-temperature application and combination with EBPR, particularly in light of the inhibitory impact of nitrites on phosphorus accumulating bacteria, are two major challenges hindering the widespread application of partial nitrification.
38 citations
TL;DR: The microbiological aspects of the biological phosphorus removal from wastewater are examined, including the basic principles of the implementation of biotechnology used in the practice of wastewater treatment for phosphorus and other nutrients.
Abstract: The review examines the microbiological aspects of the biological phosphorus removal from wastewater. The history of the development of biotechnology and the discovery of the physiological group of phosphate-accumulating organisms (PAOs), which biologically remove phosphorus via the phosphate uptake and storage in the form of intracellular polyphosphates, is briefly described. PAOs are characterized by a cyclic type of metabolism that occurs when the anaerobic/aerobic conditions cyclically change. Under anaerobic conditions, PAOs uptake and store organic compounds through the energy of degradation of intracellular polyphosphates. When anaerobic conditions change to aerobic or an alternative electron acceptor appears, PAOs uptake phosphates and synthesize intracellular polyphosphates using the intracellular polymeric sources of carbon and energy accumulated under anaerobic conditions. The main representatives of the PAOs, their metabolic models, and physiological characteristics are described. The basic principles of the implementation of biotechnology used in the practice of wastewater treatment for phosphorus and other nutrients are considered.
37 citations
TL;DR: In this paper, the current knowledge and fundamental understanding on microbiology and biochemical transformations in enhanced biological phosphorus removal (EBPR) process is revisited and a comprehensive review of EBPR design and operation with process configurations is critically reviewed.
Abstract: Phosphorus as a fundamental element for growth and metabolism of living organisms, yet problematic to water quality, is an irreplaceable component. Application of enhanced biological phosphorus removal (EBPR) technology in wastewater treatment plants offers phosphorus removal and recovery in addition to potential eutrophication prevention. This process is dependable on enrichment of phosphorus accumulating organisms in activated sludge to accumulate great amount of poly-phosphate inside their cell interior for enhancement of phosphorus removal. Yet, inadequate removal performance in pilot and full-scale systems, rises the need for optimization in operation and design of applicable configuration. In addition to applying advancement strategies to minimize the growth of undesirable microorganisms through cost effective phosphorus removal along with potential P-recovery and sustainability. Preceding research has certainly advanced the insight on this area of investigation. Notwithstanding, there are still numerous unresolved issues to be undertaken. This comprehensive review paper aims to revisit the current knowledge and fundamental understanding on microbiology and biochemical transformations in EBPR process. In view of application and structure, EBPR design and operation considerations along with process configurations is critically reviewed. This comprehensive review hopes to touch on the critical points of operation to help in understanding the overall EBPR process and to farther provide insights on future work onto EBPR process developments.
36 citations
TL;DR: In this paper, a strategy combining enhanced biological phosphorus removal and mineral P-precipitation was studied, by considering possible process modifications of a large treatment facility, and precipitation tests were conducted.
Abstract: Combined phosphorus (P) removal and recovery from wastewater is a sensible and sustainable choice in view of potential future P-resource scarcity, due to dwindling primary global reserves. P-recovery from wastewater, notwithstanding the relatively small fraction of total global amounts involved (less than 1/5 of total global use ends up in wastewater) could extend the lifespan of available reserves and improve wastewater cycle sustainability. The recovery of the resource, rather than its mere removal as ferric or aluminum salt, will still allow to achieve protection of receiving waters quality, while saving on P-sludge disposal costs. To demonstrate the possibility of such a recovery, a strategy combining enhanced biological phosphorus removal and mineral P-precipitation was studied, by considering possible process modifications of a large treatment facility. Process simulation, a pilot study, and precipitation tests were conducted. The results demonstrated that it would be possible to convert this facility from chemical -precipitation to its biological removal followed by mineral precipitation, with minimal structural intervention. Considerable P-recovery could be obtained, either in form of struvite or, more sustainably, as calcium phosphate, a mineral that also has possible fertilizing applications. The latter would present a cost about one order of magnitude lower than the former.
TL;DR: This study explored the effect of two carbon sources on performance and population structure of granular enhanced biological phosphorus removal systems at long-term low temperature by using two sequencing batch reactors, with acetate (SBR-1) and propionate ( SBR-2) as carbon sources respectively.
TL;DR: The resultant EBPR system stability and performance can be potentially controlled and optimized by manipulating the system SRT, and shorter SRT (<10 days) seems to be preferred.
Abstract: Investigations of the impact of solid residence time (SRT) on microbial ecology and performance of enhanced biological phosphorus removal (EBPR) process in full-scale systems have been scarce due to the challenges in isolating and examining the SRT from other complex plant-specific factors. This study performed a comprehensive evaluation of the influence of SRT on polyphosphate-accumulating organisms (PAOs) and glycogen-accumulating organisms (GAOs) dynamics and on P removal performance at Clark County Water Reclamation District Facility in Las Vegas, USA. Five parallel treatment trains with separated clarifiers were operated with five different SRTs ranging from 6 to 40 days. Microbial community analysis using multiple molecular and Raman techniques suggested that the relative abundances and diversity of PAOs and GAOs in EBPR systems are highly affected by the SRT. The resultant EBPR system stability and performance can be potentially controlled and optimized by manipulating the system SRT, and shorter SRT (<10 days) seems to be preferred. PRACTITIONER POINTS: Phosphorus removal performance and kinetics are highly affected by the operational solid residence time (SRT), with lower and more stable effluent P level achieved at SRT < 10 days. Excessive long SRTs above that needed for nitrification may harm EBPR performance; additionally, excessive long SRT may favor GAOs to dominate over PAOs and thus further reducing efficient use of rbCOD for EBPR. Microbial population abundance and diversity, especially those functionally relevant PAOs and GAOs, can impact the P removal performances, and they are highly dependent on the operational solid residence time. EBPR performance can be potentially controlled and optimized by manipulating the system SRT, and shorter SRT (≤10 days) seems to be preferred at the influent rbCOD/P ratio and environmental conditions as in the plant studied.
TL;DR: The results indicated that process configurations that select for slow-growing or EPS-producing heterotrophs play an important role for granule formation in full-scale CFAS systems as previously shown in SBR configurations.
TL;DR: The development of such a model able to describe in detail the microbial and chemical transformations of BNR systems with minimal adjustment to parameters suggests that the META-ASM model is a powerful tool to predict and mitigate EBPR upsets, optimise EBPR performance and to evaluate new process designs.
TL;DR: The present work demonstrated the invention of synergistically strengthen of chemical and biological removal of phosphorus (P) in biological wastewater treatment, which was achieved by exposure the bioreactors to different levels of La-based-adsorbent, and revealed that the species richness and microbial diversity varied with the different dosages of adsorbent.
TL;DR: The high enrichment of phosphate accumulating organisms in the granular sludge through bottom-feeding and selective wasting of flocs makes aerobic granularSludge resilient to morphological deterioration in aerobic presence of rbCOD.
05 Mar 2020
TL;DR: In this article, the authors demonstrate efficient and reliable combined total N, P, and chemical oxygen demand removal (70, 83, and 81%, respectively) in a sequencing batch reactor (SBR) treating real mainstream wastewater (primary effluent) at 20 °C.
Abstract: While enhanced biological phosphorus removal (EBPR) is widely utilized for phosphorus (P) removal from wastewater, understanding of efficient process alternatives that allow combined biological P removal and shortcut nitrogen (N) removal, such as nitritation–denitritation, is limited. Here, we demonstrate efficient and reliable combined total N, P, and chemical oxygen demand removal (70%, 83%, and 81%, respectively) in a sequencing batch reactor (SBR) treating real mainstream wastewater (primary effluent) at 20 °C. Anaerobic – aerobic cycling (with intermittent oxic/anoxic periods during aeration) was used to achieve consistent removal rates, nitrite oxidizing organism (NOO) suppression, and high effluent quality. Importantly, high resolution process monitoring coupled to ex situ batch activity assays demonstrated that robust biological P removal was coupled to energy and carbon efficient nitritation–denitritation, not simultaneous nitrification–denitrification, for the last >400 days of 531 total days of operation. Nitrous oxide emissions of 2.2% relative to the influent TKN (or 5.2% relative to total inorganic nitrogen removal) were similar to those measured in other shortcut N bioprocesses. No exogenous chemicals were needed to achieve consistent process stability and high removal rates in the face of frequent wet weather flows and highly variable influent concentrations. Process modeling reproduced the performance observed in the SBR and confirmed that nitrite drawdown via denitritation contributed to suppression of NOO activity.
TL;DR: C Cultivation of hAGS from autochthonous wastewater-microbes can be a promising approach for achieving biological nitrogen and phosphorus removals from hypersaline seawater-based wastewaters.
TL;DR: The values of microbial kinetic parameters such as YH and KdH in USSAS systems were higher than those in CAS systems, indicating faster microbial community renewal.
TL;DR: The results showed that the effects of GO NPs on bioreactor performances were dependent on the dose applied and the duration for which it was applied, and that Paracoccus sp.
TL;DR: This study assessed two different sludge line configurations aiming for P extraction and recovery before anaerobic digestion and compared them with the classical configuration, including a holistic approach and an optimization study of both alternatives plus their economic and environmental aspects.
TL;DR: High-resolution cellular level information is revealed regarding the metabolic flexibility in PAOs, phenotypic stoichiometry changes and carbon flux and distribution among PAOs and GAOs, in response to influent loading conditions, to contribute to improvement in mechanistic EBPR modeling and design.
TL;DR: The possibility to exploit the biological phosphorus removal in plant (C), by adjusting the aeration conditions, was explored and an economic analysis showed this to be a preferable approach with respect to the chemical removal of phosphorus.
TL;DR: Higher endogenous NUR in ASSR than in anoxic tank also indicated that ASSR and carriers both accelerated sludge decay, indicating that denitrification and sludge reduction occurred inASSR played important roles in biological nutrient removal.
TL;DR: The mechanism study revealed that the presence of 500 μg/L NOR inhibited anaerobic phosphorus release and acetate uptake as well as aerobic phosphorus uptake during long-term exposure and suppressed the activity of key enzymes related to phosphorus removal.
TL;DR: Investigation of the biotransformation of P in two EBPR sludge biochars reveals that P released from biochar produced at 700 °C (E700) was more easily absorbed by P. putida than that released fromBiochar produced in E400, which is attributed to the higher polyphosphates (poly-P) content in E700 and poly-P has higher affinity to P.–putida surface compared to orthophosphates.
TL;DR: It was confirmed that the EBPR process was related to the combined action of extracellular and intracellular poly-P using a new fractionation method of P in EBPR sludge, which included the ultrasonic protocol at high power density for extracting the intrACEllular P and its poly- P.
TL;DR: The highest P-release amount and rate were found in highly-enriched PAO sludge samples, but with fewer influences on thesludge collected from WWTP, which may be attributed to the lower fraction of PAOs in the sludge.
TL;DR: PAC addition effectively inhibited the proliferation of filamentous bacteria, indicating its potential in inhibiting the sludge filamentous bulking and guidance for the selection of the phosphorus removal process and operational conditions.