The Blue Plains Advanced Wastewater Treatment Plant (AWTP) in Washington, DC has a high rate activated sludge system followed by a suspended growth nitrification-denitrification system. Methanol is used for post-denitrification, because it is the least expensive synthetic compound available that does not leave residual biochemical oxygen demand (BOD) in the process effluent. The process achieves ...
A membrane bioreactor (MBR) was developed to achieve nitrogen removal by combining nitrification and denitrification conditions in one reactor. The activated sludge was alternated between aerobic and anoxic conditions using peristaltic pump. The biomass concentration and floc morphological properties were observed to be similar in anoxic and aerobic compartments. However, the homogeneous ...
Simultaneous nitrification and denitrification (SND), which is more economical compared with the traditional method for nitrogen removal, is studied in this paper. In order to find the suitable conditions of this process, a mixed flow activated sludge system under low oxygen concentration is investigated, and some key control parameters are examined for nitrogen removal from synthetic wastewater. ...
The operation of biological wastewater treatment systems performing simultaneous nitrificationdenitrification (SND) was simulated using Activated Sludge Model No. 1 (ASM1). Properties and parameters typical of domestic sewage were used in the simulations. System performance was simulated under a range of conditions to identify an appropriate operating window for the process. Simulation results ...
Concurrent nitrification and denitrification (CND) are natural phenomena in the soil environment that can be applied in wastewater treatment for enhanced total nitrogen removal. However, significant renovation is necessary for existing plants to equip them for nutrient removal. At a domestic wastewater treatment plant, we performed a pilot test by installing bioplates with entrapped biomass in a ...
ABSTRACT As part of a nutrient reduction program, developed to meet new Virginia ENR requirements, two innovative denitrification technologies were piloted at the Noman Cole Jr. Water Pollution Control Plant in Fairfax County, Virginia. The first technology was a Moving Bed Biofilm Reactor (MBBR). The second technology was a modified Integrated Fixed Film Activated Sludge (IFAS) ...
Nitrate concentration in the final effluent is a key issue in pre-denitrification biological treatment systems. This study investigated post-denitrification with alginate beads containing immobilized activated sludge microorganisms and organic carbon source. A batch study was first performed to identify suitable carbon sources among acetate, glucose, calcium tartrate, starch and canola oil on ...
The use of fusel oil as an ‘alternative’ carbon source for denitrification in the mainstream and sidestream treatment processes was studied. Research comprised two kinds of batch experiments as well as acclimation of process biomass to external carbon sources. In the conventional nitrate utilization rate (NUR) measurements (one-phase experiments with non-acclimated biomass), the NUR with fusel ...
The efficiencies of denitrification and enhanced biological phosphorus removal (EBPR) in biological nutrient removal (BNR) activated sludge systems are strongly dependent on the availability of appropriate carbon sources. Due to high costs of commercial compounds (such as methanol, ethanol, acetic acid etc.) and acclimation periods (usually) required, the effective use of internal carbon sources ...
An integrated fixed-film activated sludge (IFAS) process (G1) and an activated sludge anoxic–oxic process (G2) were operated at nitrate liquor recirculation ratio (R) of 100, 200 and 300% to investigate the feasibility of enhancing nitrogen removal efficiency (RTN) and reducing R by improving simultaneous nitrification and denitrification (SND) in the IFAS process. The results ...
Recently, the research focused on the development and operation of aerobic granular biomass has increased in interest, due to the advantages of this option as compared to the conventional activated sludge systems traditionally used for the biological treatment of wastewater. The aerobic granular sludge is produced in Sequential Batch Reactors (SBR) where a large amount of biomass is accumulated ...
High nitrogen discharge from wastewater impacts negatively on the marine environment. Under the South Australian Environmental Improvement Program, metropolitan wastewater treatment plants are reconfigured to meet the new nitrogen discharge guideline. The denitrification process is carbon limited with carbon supplementation required to meet discharge guidelines, hence molasses is used for carbon ...
A parameter estimation framework was used to evaluate the ability of observed data from a full-scale nitrification–denitrification bioreactor to reduce the uncertainty associated with the bio-kinetic and stoichiometric parameters of an activated sludge model (ASM). Samples collected over a period of 150 days from the effluent as well as from the reactor tanks were used. A hybrid genetic ...
ABSTRACTThe possibility of co-treating municipal and winery wastewaters in a conventional activated sludge process was studied at full scale. The wastewater treatment plant considered in this paper operated an extended-oxidation process during vintage (four month per year) and a pre-denitrification/oxidation process during the rest of the year. The experimentation showed that good performances, ...
ABSTRACTThe Greenville Utilities Commission Wastewater Treatment Plant (GUC WWTP) is a 17.5 mgd treatment plant designed to meet effluent total nitrogen and total phosphorus limits of 6.0 mg/L and 2.0 mg/L, respectively, through biological nutrient removal. The treatment plant is divided into two separate activated sludge systems; the north and south plants. The treatment plant has consistently ...
Research was undertaken to calibrate and verify the Aquifas semi-empirical and biofilm 1D models against a full scale Integrated Fixed-Film Activated Sludge (IFAS) system. The model was then used to evaluate and identify alternatives to upgrade the performance of tertiary IFAS system and Moving (mobile) Bed Biofilm Reactor (MBBR) systems that could minimize volume required for nitrogen removal. ...
Abstract New Activated Sludge (NAS) represents a hybrid, floc-based nitrogen removal process, based on the control of solids retention times (SRT) and dissolved oxygen (DO) levels. The aim of this study was to examine the performance of a full-scale NAS plant, which treated anaerobically digested industrial wastewater. The batch-fed partial nitritation step oxidized ...
The immobilized cell augmented activated sludge (ICAAS) system combines a cell immobilization technique and an off-line enricher-reactor for the bioaugmentation of activated sludge system to improve treatment performances. In this study, enhanced nitrogen removal using ICAAS was investigated. Laboratory-scale, off-line, batch enricher-reactors were used to maintain nitrification and ...
ABSTRACT The hybrid membrane biofilm process (HMBP) is a novel technology for removing total nitrogen (TN) from municipal wastewater. Air-filled, hollow-fiber membranes are placed in an activated sludge basin, and the bulk liquid is left anoxic. The membranes support an aerobic, nitrifying biofilm, while produced nitrite and/or nitrate is exported to the bulk liquid and reduced with BOD as ...
A lab-scale Cyclic Activated Sludge Technology (CAST) system was operated more than 5 months to evaluate the effects of the operation mode on nitrogen removal performance and investigate a feasible method for achieving short-cut nitrification in the system. Results showed that nitrogen was removed by conventional biological nitrification and denitrification in traditional operation mode ...