Full scale evaluation of nitrification performance in an integrated fixed film activated sludge process

1998 ◽  
Vol 38 (1) ◽  
pp. 71-78 ◽  
Author(s):  
R. M. Jones ◽  
D. Sen ◽  
R. Lambert
Keyword(s):  
Activated Sludge ◽  
Monitoring And Evaluation ◽  
Full Scale ◽  
Nitrification Rate ◽  
Operating Period ◽  
Monitoring Period ◽  
Media Frames ◽  
Average Temperature ◽  
Fixed Film ◽  
The Media

The nitrification performance of an integrated fixed film activated sludge (IFAS) process was compared to a parallel control system at full scale. The IFAS process utilized the Ringlace and Biomatrix looped cord media products. Monitoring and evaluation of the retrofit was divided into two periods. The first monitoring period was from October 3, 1995 to June 20, 1996. The second monitoring period was started on December 2, 1996 and was completed on March 28, 1997. During the first operating period, the maximum media nitrification rate was estimated to be 0.42 kg/d/1000 m of media at an average temperature of 10°C. Settling was also improved. To correct flow short circuiting observed during the first operating period additional aerators were mounted below the media frames and baffles were mounted above existing diffusers. Nitrification performance of the media during the second operating period was found to be marginal. Although the nitrification performance in the control train was not stressed to the same degree as in the 1995/96 period, the likely main cause of the deteriorated performance of the media was a proliferation of bristle worm in the biofilm. The results of this study indicate that proper aeration design, and the prevention and treatment of worm blooms are two important issues in the application of the IFAS process.

Full-scale evaluation of an integrated fixed-film activated sludge (IFAS) process for enhanced nitrogen removal

1996 ◽  
Vol 33 (12) ◽  
pp. 155-162 ◽  
Author(s):  
Clifford W. Randall ◽  
Dipankar Sen
Keyword(s):  
Activated Sludge ◽  
Nitrogen Removal ◽  
Plug Flow ◽  
Treatment Plant ◽  
Nitrification Rate ◽  
A Value ◽  
Fixed Film ◽  
Control Section ◽  
The Media ◽  
Retrofit Design

One of the two trains of the 37,000 m3/d Annapolis, Maryland step aeration activated sludge treatment plant was modified for single-sludge anoxic-aerobic operation, and then fixed-film media were integrated into the aerobic zone to enhance nitrification. Rope-like Ringlace media was selected for integration, and 30,000 meters were installed in a volume of 475 m3 for a pilot demonstration. The purpose of the integrated fixed-film media was to upgrade the short hydraulic retention time (HRT) basin (6 hrs nominal) for efficient, year-round nitrogen removal without construction to increase basin volume. An engineering study had concluded that upgrading the facility for year round complete nitrification, without nitrogen removal, would cost US$24 million. The modified train was operated for 12 months, six in the plug-flow MLE configuration, and six in a step-feed configuration. The integrated Ringlace media increased the nitrification rate per unit volume to 225% of that observed in the control section, attaining a value of 1.75 kg/d NH3-N per linear meter at 15°C. The media also increased denitrification in the aerobic media section to the extent that between 30 and 88% of the nitrates formed in the section were denitrified within it, permitting a potential 25% or more reduction in the volume of the anoxic zone. An IFAS retrofit design was developed which incorporated step-feed operation, and reduced the projected construction cost to US$9.2 million.

Practical experience with full-scale structured sheet media (SSM) integrated fixed-film activated sludge (IFAS) systems for nitrification

2014 ◽  
Vol 71 (4) ◽  
pp. 545-552 ◽  
Author(s):  
Hua Li ◽  
Jia Zhu ◽  
James J Flamming ◽  
Jack O'Connell ◽  
Michael Shrader
Keyword(s):  
Activated Sludge ◽  
Wastewater Treatment Plants ◽  
Contact Process ◽  
Plug Flow ◽  
Oxygen Demand ◽  
Cost Effective ◽  
Practical Experience ◽  
Full Scale ◽  
Fixed Film ◽  
The Usa

Many wastewater treatment plants in the USA, which were originally designed as secondary treatment systems with no or partial nitrification requirements, are facing increased flows, loads, and more stringent ammonia discharge limits. Plant expansion is often not cost-effective due to either high construction costs or lack of land. Under these circumstances, integrated fixed-film activated sludge (IFAS) systems using both suspended growth and biofilms that grow attached to a fixed plastic structured sheet media are found to be a viable solution for solving the challenges. Multiple plants have been retrofitted with such IFAS systems in the past few years. The system has proven to be efficient and reliable in achieving not only consistent nitrification, but also enhanced bio-chemical oxygen demand removal and sludge settling characteristics. This paper presents long-term practical experiences with the IFAS system design, operation and maintenance, and performance for three full-scale plants with distinct processes; that is, a trickling filter/solids contact process, a conventional plug flow activated sludge process and an extended aeration process.

scholarly journals Fate of selected pharmaceutically active compounds in the integrated fixed film activated sludge process

2017 ◽  
Vol 75 (11) ◽  
pp. 2680-2691 ◽  
Author(s):  
K. J. Murray ◽  
W. J. Parker ◽  
L. M. Bragg ◽  
M. R. Servos
Keyword(s):  
Activated Sludge ◽  
Municipal Wastewater ◽  
Nitrification Rate ◽  
Process Conditions ◽  
Batch Reactors ◽  
Experimental Conditions ◽  
Conventional Activated Sludge ◽  
Fixed Film ◽  
Solids Retention ◽  
Biomass Activity

The potential for integrated fixed film activated sludge (IFAS) processes to achieve enhanced transformation of pharmaceuticals relative to conventional activated sludge (CAS) processes was assessed. Previous studies have focused on direct comparisons of parallel reactors with and without fixed film carriers and little information is available on the impacts of how varying operating parameters impact the differences in observed pharmaceutical compound (PC) transformation capabilities between CAS reactors and those equipped with both an activated sludge (AS) and fixed film carriers. The testing was carried out using bench scale sequencing batch reactors fed with authentic municipal wastewater and operated at selected combinations of temperature and solids retention time (SRT). PC transformation efficiencies were assessed in a 22 factorial design that employed the IFAS and CAS processes, operated in parallel under identical process conditions. Nitrification rate testing that was conducted to obtain insight into the biomass activity demonstrated that IFAS consistently had improved nitrification kinetics despite lower mixed liquor volatile suspended solids levels thereby demonstrating the contribution of the biofilm to nitrification. Increased transformation of atenolol (ATEN; ranging from 10–60%) and trimethoprim (TRIM; ranging from 30–50%) in the IFAS equipped reactors relative to their respective activated sludge (AS) controls was observed under all experimental conditions. Negligible transformation of carbamazepine was observed in both reactors under all conditions investigated. More than 99% of acetaminophen was transformed in both configurations under all conditions. There was no correspondence between nitrification activity and TRIM removal in the control AS while conditions that stimulated nitrification in the control AS also resulted in enhanced removal of ATEN. The results of this study indicate that the integration of biofilms in AS processes enhances transformation of some PCs.

Validating the Colloid model to optimise the design and operation of both moving-bed biofilm reactor and integrated fixed-film activated sludge systems

2014 ◽  
Vol 69 (7) ◽  
pp. 1552-1557 ◽  
Author(s):  
J. Albizuri ◽  
P. Grau ◽  
M. Christensson ◽  
L. Larrea
Keyword(s):  
Activated Sludge ◽  
Oxygen Demand ◽  
Biofilm Reactor ◽  
Nitrification Rate ◽  
Moving Bed Biofilm Reactor ◽  
Moving Bed ◽  
Fixed Film ◽  
Solids Retention ◽  
Lower Effect ◽  
Activated Sludge Systems

The paper presents a systematic study of simulations, using a previously calibrated Colloid model, from which it was found that: (i) for pure moving-bed biofilm reactor (MBBR) processes with tertiary nitrification conditions (no influent chemical oxygen demand (COD)), dissolved oxygen = 5 mg/L and residual NH4-N > 4 mgN/L, a nitrification rate of 1.2 gN/(m2d) was obtained at 10 °C. This rate decreases sharply when residual NH4-N is lower than 2 mgN/L, (ii) for MBBR systems with predenitrification–nitrification zones and COD in the influent (soluble and particulate), the nitrification rate (0.6 gN/(m2d)) is half of that in tertiary nitrification due to the effect of influent colloidal XS (particulate slowly biodegradable COD) and (iii) for integrated fixed-film activated sludge (IFAS) processes the nitrification rate in the biofilm (0.72 gN/(m2d)) is 20% higher than for the pure MBBR due to the lower effect of influent XS since it is adsorbed onto flocs. However, it is still 40% lower than the tertiary nitrification rate. In the IFAS, the fraction of the nitrification rate in suspension ranges from 10 to 70% when the aerobic solids retention time varies from 1.4 to 6 days.

Phosphorus Removal and PAOs Populations at a Full-Scale Integrated Fixed-Film Activated Sludge (IFAS) Plant

2008 ◽  
Vol 2008 (17) ◽  
pp. 1-17 ◽  
Author(s):  
Annalisa Onnis-Hayden ◽  
Nehreen Majed ◽  
Katherine D. McMahon ◽  
April Z. Gu
Keyword(s):  
Activated Sludge ◽  
Phosphorus Removal ◽  
Full Scale ◽  
Fixed Film

Estimation of Biomass Concentration and Population Dynamics in a Captor® Activated Sludge System

1994 ◽  
Vol 29 (7) ◽  
pp. 149-152 ◽  
Author(s):  
M. P. Reddy ◽  
K. R. Pagilla ◽  
P. R. Senthilnathan ◽  
H. W. Johnson ◽  
P. S. Golla
Keyword(s):  
Population Dynamics ◽  
Activated Sludge ◽  
Microbial Population ◽  
Biomass Concentration ◽  
Activated Sludge Process ◽  
Free Swimming ◽  
Activated Sludge System ◽  
Suspended Growth ◽  
Fixed Film ◽  
The Media

A technique was developed to measure the equivalent MLSS in the fixed film Captor® media-activated sludge process. The technique accounts for the wear in the media as well as unequal wear in different media. The microbial population variations encountered during three years of full scale operation of the Captor® process, at the Moundsville WWTP were recorded. It has been found that fixed film media seem to support predominantly rotifers, followed by free swimming ciliates, and single stalk ciliates. In contrast, the suspended growth activated sludge population contained lower level organisms, mostly free swimming ciliates, followed by stalk ciliates, flagellates, and a few rotifers.

Full-scale application of the BABE® technology

2004 ◽  
Vol 50 (7) ◽  
pp. 87-96 ◽  
Author(s):  
S. Salem ◽  
D.H.J.G. Berends ◽  
H.F. van der Roest ◽  
R.J. van der Kuij ◽  
M.C.M. van Loosdrecht
Keyword(s):  
Activated Sludge ◽  
Treatment Plant ◽  
Full Scale ◽  
Nitrification Rate ◽  
Stable Operation ◽  
Water Line ◽  
Ambient Temperatures ◽  
N Removal ◽  
Set Up ◽  
Activated Sludge Processes

Bio-augmentation can be used to obtain nitrification in activated sludge processes that operate at ub-optimal solid retention times. A side-stream process, the so-called BABE® process that incorporates Nremoval and augmentation of nitrifiers has been developed. The principle is to implement a nitrification reactor in the sludge return line, the so-called BABE reactor. This reactor can be fed with an internal N-rich flow (e.g. effluent from the sludge treatment). Hence the nitrification capacity of an activated sludge process can be augmented by the addition of nitrifiers cultivated in the BABE reactor. A full-scale test of the BABE technology has been at the treatment plant Garmerwolde in Groningen, the Netherlands. The set-up allowed comparing between three different lines: with the BABE reactor, without rejectwater and with untreated rejectwater. Based on this, the two important tasks (N-removal and inoculation) performed by the BABE reactor could be quantified. The results of the practical work in Garmerwolde showed a higher nitrification rate in the water line where the BABE reactor was implemented and also lower effluent ammonia. The experiments on a practical scale have demonstrated univocally the effective and stable operation of the BABE technology. In addition, sludge samples in different streams as well as from the BABE reactor were analysed with FISH technique. The FISH results illustrated the augmentation effect of the BABE reactor on the stream with the BABE reactor. A mathematical model, based on ASM1 model and implemented in AQUASIM was developed and used for simulating the treatment plant of Garmerwolde. The simulation results indicated that better effect of the BABE technology is expected at lower ambient temperatures and smaller volume of the BABE reactor. The BABE reactor could also allow for providing more space for de-nitrification in the main water line when nitrification is efficient enough.

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