scholarly journals Use of ion exchange for removal of Ammonium: A biological regeneration of zeolite

2013 ◽  
Vol 8 (2) ◽  
pp. 146-150
Keyword(s):  
Ion Exchange ◽  
Treatment Plant ◽  
Domestic Wastewater ◽  
Exchange Capacity ◽  
Nitrifying Bacteria ◽  
Aeration Tank ◽  
Nitrate Anion ◽  
High Concentration ◽  
Column System ◽  
Clinoptilolite Zeolite

Nitrogen in the Ammonia form can have deleterious effects in water resources. Ion Exchange by zeolite and biological Nitrification processes are two proposed methods for removing Nitrogen compounds from wastewater and effluents. The main objective of this research was to investigate the efficiency of nitrifying bacteria for regenerating Clinoptilolite zeolite. In this research, the Semnan Clinoptilolite zeolite was supplied in mesh 30. Then the capacity of zeolite in ammonium removal was determined in column system. To cultivate of nitrifying bacteria a sludge sample was taken from a domestic wastewater treatment plant and added to a 15 l aeration tank. Ammonium and other nutrients were added in the reactor daily over a month period and the effect of nitrate anion and MLVSS on nitrification process have been determined. After saturation of zeolite with ammonium, biological regeneration was done by contact of zeolite and nitrifying bacteria in column system. In this stage slurry of nitrifying bacteria is pumped up flow through the zeolite column and recycled to the aeration tank. The effluent containing the displaced ammonium is oxidized to nitrate by the nitrifying bacteria. Then the nitrified brine is clarified in a sedimentation tank and stored for reuses. The results showed that the cation exchange capacity was 10.06 (in breakthrough point) and 18.38 mg NH4+ g-1 zeolite as total capacity. The results indicated that nitrification accelerated by increasing in MLVSS concentration and concentration of nitrate remains in solution. The results obtained from bioregeneration tests of zeolite showed that the efficiency was 87.7 to 99.8% in period of 3.5 to 5.5 hours. Based on the results, since regeneration is achieved in high concentration of nitrate, the use of nitrifying sludge in several cycles is possible and the use of system can be appreciated to an alternative economical method for removing NH4+ from effluent.

scholarly journals Simultaneous removal of BOD, N and P in a single continuous flow real scale activated sludge reactor with cyclic aeration

2020 ◽  
Vol 15 (1) ◽  
pp. 201-212
Author(s):  
Álvaro Orozco-Jaramillo ◽  
Santiago Vélez-Velásquez
Keyword(s):  
Continuous Flow ◽  
Treatment Plant ◽  
Domestic Wastewater ◽  
Aeration Tank ◽  
Domestic Wastewater Treatment ◽  
Stable Conditions ◽  
Activated Sludge Reactor ◽  
Anoxic Environment ◽  
Real Scale ◽  
Composite Samples

Abstract The present study evaluates the performance of a real scale domestic wastewater treatment plant (WWTP), operating under continuous flow conditions with ‘extremely high sludge age’, designed to remove organic matter and perform nitrification-denitrification within a single reactor under cyclic aeration. Composite samples were withdrawn from the reactor for one week and their analysis results compared satisfactorily with the calculations of the design models. The WWTP is operating under stable conditions with a BOD5 removal of 86%, COD removal of 87%, TKN removal of 73% and, unexpectedly, a stable removal of 55% of total phosphorus. The design of the WWTP is simple and consists of a single aeration tank with a kinetic selector and a secondary sedimentation tank, operating under cyclic conditions in the aeration tank, with 45-minute aeration on (oxic environment) and 15 minutes aeration off (anoxic environment). The system can be applied to upgrade WWTP from secondary to tertiary treatment with only small modifications. A phosphorus removal mechanism is also proposed.

Aerated Biofilters for Nitrification and Effluent Polishing

1990 ◽  
Vol 22 (7-8) ◽  
pp. 181-189 ◽  
Author(s):  
Catherine Paffoni ◽  
Michel Gousailles ◽  
Frank Rogalla ◽  
Pierre Gilles
Keyword(s):  
Activated Sludge ◽  
Suspended Matter ◽  
Ammonia Oxidation ◽  
Treatment Plant ◽  
Packed Bed ◽  
Nitrifying Bacteria ◽  
Innovative Technology ◽  
High Concentration ◽  
Conventional Activated Sludge ◽  
Paris Area

To comply with new effluent discharge standards of 10 mg TKN/l, different upgrading methods for a highly loaded activated sludge plant were explored. As a conclusion, demonstration units were tested to assess process feasibility and performance data of an innovative technology. The Achères Treatment plant of the city of Paris is currently being extended to purify a flow of about 2 700 000 m3/d, corresponding to 8 Million population equivalents. Conventional activated sludge, loaded at about 0.6 kg BOD/kg SS d, delivers an effluent of 30 mg/l for both BOD and SS. To achieve nitrification, a considerable multiplication of basin volume and clarifier area would be required. In the densely urbanised Paris area, insufficient space is available for a such an extension. Therefore, new technology for plant upgrading was tested on industrial scale. Biological aerated filters combine aerobic degradation of pollutants with physical retention of suspended solids in one reactor. A high concentration of active biomass can be retained in the packed bed, and nitrifying bacteria can be attached to the filter media. Removal efficiency becomes thus independent of clarification and sludge settling, and ammonia oxidation can be achieved without sludge age requirements. Four parallel units were installed on the Colombes research platform, handling a total flow of 3000 m3/d. An extensive demonstration test program was carried out over a period of five years to assess the feasibility and performances of the process in line with a conventional activated sludge plant. The limits of loading to achieve different residual ammonia concentrations were studied, and the influence of temperature on biological and hydraulic parameters was verified. Backwash requirements and residual values of carbonaceous and suspended matter were explored in dependence on influent values and filtration velocity. At 13 °C, an ammonia load of 0.5 kg N/m3 d was completely oxidized. A concentration of 20 mg/l N-NH4 can thus be totally converted with an empty bed contact time of 1 hour. The Arrhenius temperature coefficient for nitrification was measured as 1.05. Biodegradable carbonaceous and suspended matter was completely removed at filtration velocities higher than 4 m/h, yielding an effluent of less than 5 mg/l for both SS and BOD. Backwash frequency was less than once per day, and a maximum of 5 % of the filter flowrate was used for backwashing.

Quantifying solute transport processes: Are chemically “conservative” tracers electrically conservative?

Geophysics ◽  
2011 ◽  
Vol 76 (1) ◽  
pp. F53-F63 ◽  
Author(s):  
Kamini Singha ◽  
Li Li ◽  
Frederick D. Day-Lewis ◽  
Aaron B. Regberg
Keyword(s):  
Mass Transfer ◽  
Ion Exchange ◽  
Solute Transport ◽  
Exchange Capacity ◽  
Transport Processes ◽  
Surface Conductance ◽  
Exchange Reactions ◽  
High Concentration ◽  
Temporal Variance ◽  
Reactive Processes

The concept of a nonreactive or conservative tracer, commonly invoked in investigations of solute transport, requires additional study in the context of electrical geophysical monitoring. Tracers that are commonly considered conservative may undergo reactive processes, such as ion exchange, thus changing the aqueous composition of the system. As a result, the measured electrical conductivity may reflect not only solute transport but also reactive processes. We have evaluated the impacts of ion exchange reactions, rate-limited mass transfer, and surface conduction on quantifying tracer mass, mean arrival time, and temporal variance in laboratory-scale column experiments. Numerical examples showed that (1) ion exchange can lead to resistivity-estimated tracer mass, velocity, and dispersivity that may be inaccurate; (2) mass transfer leads to an overestimate in the mobile tracer mass and an underestimate in velocity when using electrical methods; and (3) surface conductance does not notably affect estimated moments when high-concentration tracers are used, although this phenomenon may be important at low concentrations or in sediments with high and/or spatially variable cation-exchange capacity. In all cases, colocated groundwater concentration measurements are of high importance for interpreting geophysical data with respect to the controlling transport processes of interest.

Tailoring of highly efficient nitrifying biofilms in fluidized bed for ammonia-rich industrial wastewater treatment

2000 ◽  
Vol 42 (3-4) ◽  
pp. 357-362 ◽  
Author(s):  
S. Tsuneda ◽  
T. Miyoshi ◽  
Y. Aoi ◽  
A. Hirata
Keyword(s):  
Fluidized Bed ◽  
Industrial Wastewater ◽  
Domestic Wastewater ◽  
Nitrifying Bacteria ◽  
Nitrification Rate ◽  
Fish Analysis ◽  
Ammonia Oxidizing Bacteria ◽  
High Concentration ◽  
Stepwise Reduction ◽  
Biofilm Structure

We proposed two tailoring methods for efficient nitrifying biofilms on particles which are expected to be used in fluidized bed in nitrogen removal processes for industrial wastewaters. The first method was examined with gradual reduction of the hydraulic retention time in continuous feeding reactor to form biofilm with high nitrification ability. As a result, nitrification rate was successfully improved mainly due to acclimation of nitrifying bacteria to higher loading. The second tailoring method for nitrifying biofilm started with the biofilm which had been previously constructed in synthetic domestic wastewater containing high concentration of NH4+-N as well as various biodegradable organic compounds. Stepwise reduction of C/N ratio in inlet wastewater was performed during one month simultaneously with observation of microbial population dynamics in the biofilm using fluorescent in situ hybridization (FISH) analysis. As a result, this acclimation process promoted occupation of the biofilm by ammonia-oxidizing bacteria and resulted in making suitable biofilm structure for nitrification of ammonia-rich industrial wastewater. Moreover, it is confirmed that this new tailoring method greatly shortened required time to obtain nitrifying biofilms.

scholarly journals MEJORAMIENTO DE LA CALIDAD MICROBIOLÓGICA DE BIOSÓLIDOS GENERADOS EN PLANTAS DE TRATAMIENTO DE AGUAS RESIDUALES DOMÉSTICAS (MICROBIOLOGICAL QUALITY IMPROVEMENT OF BIOSOLIDS FROM DOMESTIC WASTEWATER TREATMENT PLANTS)

Revista EIA ◽  
2013 ◽  
Vol 6 (11) ◽  
pp. 21
Author(s):  
Patricia Torres ◽  
Carlos Madera ◽  
Jorge Silva
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Microbiological Quality ◽  
Domestic Wastewater ◽  
Nutrient Content ◽  
Pilot Scale ◽  
High Concentration ◽  
Domestic Wastewater Treatment ◽  
Class B

Uno de los principales problemas de calidad que presentan los biosólidos de plantas de tratamiento de aguas residuales domésticas –PTAR– es el contenido de microorganismos patógenos que los clasifica en muchos casos como Clase B con restricción para uso agrícola. Este estudio evaluó la estabilización alcalina de los biosólidos de la PTAR Cañaveralejo (Cali, Colombia) para mejorar su calidad microbiológica, empleando dos tipos de cal (hidratada y viva) en dosis entre 8 y 25 % y dos tipos de ceniza con dosis entre 8 y 40 % en unidades experimentales de 0,2 m2 con un tiempo de contacto de 13 días. Los resultados mostraron que con cal se logró reducción total de las variables de respuesta evaluadas (coliformes fecales, Salmonella sp y huevos de helmintos), mientras que el poder alcalinizante de las cenizas evaluadas fue insuficiente. El biosólido higienizado con cal presenta alto potencial de uso agrícola por su calidad microbiológica y por el contenido final de materia orgánica y nutrientes (N, P) que pueden beneficiar los suelos, pero es recomendable evaluar la optimización a escala piloto de la dosificación de cal y la aplicación del biosólido en diferentes tipos de suelos y cultivos para precisar los beneficios o medidas preventivas antes de la aplicación.Abstract: One of the main quality problems of biosolids from domestic wastewater treatment plants –WWTP– is the high concentration of pathogens, often classified as a class B, with restriction for use in agriculture. This study evaluated the alkali stabilization of biosolids from Cañaveralejo wastewater treatment plant (PTAR-C), located in Cali, Colombia, in order to improve their microbiological quality using two types of lime (quick and hydrated) with doses between 8 to 25 % and two types of ash with 8 to 40 % as doses, in experimental units 0,2 m2with 13 days of contact time. The results showed that both type of lime reached the total reduction of evaluated monitoring variables (faecal coliforms, Salmonella sp, helmints eggs) while the alkali power of ashes were lower. The obtained biosolids treated with lime have a high potential use in agriculture purposes for the good microbiological quality, and for the organic matter and nutrient content (N, P) that can generate benefit to the soil, but it is recommendable to evaluate at pilot scale the lime doses and application of biosolid in different soils types and crops in order to precise the benefits or prevent measurements before application of material in soil.

Colour removal by ion exchange and reuse of regenerant by means of nanofiltration

2004 ◽  
Vol 4 (5-6) ◽  
pp. 57-64 ◽  
Author(s):  
D. Schippers ◽  
M. Kooi ◽  
P. Sjoerdsma ◽  
F. de Bruijn
Keyword(s):  
Ion Exchange ◽  
Treatment Plant ◽  
Exchange Capacity ◽  
Operating Conditions ◽  
Waste Stream ◽  
Design Parameters ◽  
Simultaneous Occurrence ◽  
Water Type ◽  
Pilot Studies ◽  
Exchange Processes

In the past year Vitens, The Netherlands' largest water supply company, and Witteveen+Bos, have prepared the preliminary, basic and detailed design for a full-scale ion exchange plant reducing colour in drinking water to a value of less than 10 mg/l PtCo. Current pilot study shows that the results are even better than expected. The plant will be built in 2004 and start-up is scheduled for mid 2005. The introduction of ion exchange at WTP (Water Treatment Plant) Oldeholtpade is part of a larger project, also including softening in pellet reactors, preceded by counter-current aeration and renovation of the existing treatment plant. The colour content present in groundwater is caused by peat layers. In contrast with conventional ion exchange processes, previous pilot studies showed that the exchange capacity of the resin for organics is much larger than expected. The excellent results can be explained by assuming the simultaneous occurrence of adsorption and ion exchange processes on the resin. It can be concluded that optimising operating conditions, such as higher exchange capacity (as KMnO4/liter resin), higher superficial velocity, shorter contact time and longer filter run cycle clearly affect resin volume as well as the required amount of regenerant. Vitens has started additional experiments at WTP Spannenburg to confirm the innovative design parameters. Aim of the research is the relation between adsorption and ion exchange during filtration, in order to clarify the achieved results. Furthermore the relationship between the specific water type (characterisation of organic compounds) and the operational results of ion exchange will be studied. In order to minimise the waste regenerant, treatment towards recycling is studied by dead end nanofiltration. With nanofiltration it is possible to concentrate the waste stream to a maximum of 10% of the original waste stream. The recovered regenerant can be recycled for regeneration of the resin.

scholarly journals Determination on inhibition effects of coagulants used in wastewater treatment plants on anaerobic digester

2020 ◽  
Vol 82 (9) ◽  
pp. 1877-1884
Author(s):  
Güler Türkoğlu Demirkol ◽  
Gökhan Balcıoğlu ◽  
Nurtaç Öz ◽  
Moiz Elnekave ◽  
Bülent Armağan ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Settling Tank ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
High Concentration ◽  
Biological Methods ◽  
Solids Removal

Abstract Domestic wastewaters causing pollution contain inorganic and/or organic materials. When the domestic wastewater outflows to the receiving waters, it causes physical, chemical, and biological pollution in them, and deteriorates the ecological balance of those waters. In the treatment of wastewater, various treatment methods are available depending on the pollution strength of the wastewater. Besides mechanical and biological methods, wastewater treatment with physicochemical methods is still one of the most effective and economical options. Particularly in wastewater with a high concentration of suspended solids, this method is very successful, and obtaining high suspended solids removal efficiencies is very possible. In this study, the effects of the use of coagulant and coagulant aid to be used in a treatment plant where domestic wastewater treatment is carried out are determined to increase the treatment efficiency of a biological treatment that comes later in the stages of the treatment. The effluent of the pre-settling tank may contain a lot of suspended solids. This presence of excess suspended solids decreases the efficiency at other levels of treatment and causes energy loss. In the experiments, the standard jar and inhibition tests are done as a method. As a result of the conducted studies, it is determined that the FeCl3, Synthetic coagulant LP 526, FeClSO4, and the combination of anionic polyelectrolyte yield the best results in the removal of the parameters of chemical oxygen demand (COD), total suspended solids (TSS), and volatile suspended solids (VSS). While FeCl3, APE 65, APE 85, Synthetic coagulant LP 526, and FeClSO4 did not show any inhibition effect in the sludge, APE 67, CPE 84, and (Al2(SO4)3 are found to cause inhibition in the sludge.

scholarly journals Determination of kinetic parameters in activated sludge process for domestic wastewater treatment plant

2007 ◽  
Vol 13 (4) ◽  
pp. 211-215 ◽  
Author(s):  
Ghasem Najafpour ◽  
Maedeh Sadeghpour ◽  
Zinatizadeh Lorestani
Keyword(s):  
Activated Sludge ◽  
Rate Constant ◽  
Large Scale ◽  
Oxygen Transfer Rate ◽  
Treatment Plant ◽  
Domestic Wastewater ◽  
Cod Removal ◽  
Growth Rate Constant ◽  
Aeration Tank ◽  
Activated Sludge Process

The process was effectively used for the treatment of domestic wastewater known as the activated sludge process. To predict the biomass growth, the Monod rate equation was applied in a 30 liter(s) aerated and agitated vessel. The projected data for the kinetic model were used to estimate the large scale aeration tank for the efficient oxygen transfer rate. Food to microorganism ratio (F/M) and HRT were examined for the desired rate of COD removal. More than 52% yield of organic removal was obtained. Also, the endogenous decay coefficient of 0.06 d-1 was obtained. The growth rate constant (Ks) and rate constant (k) were determined as 85.5 mg/l and 1.71 d-1, respectively. 90% COD removal was achieved with the eight-day-old sludge.

scholarly journals Investigation of dissolved N2O production processes during wastewater treatment system in Ulaanbaatar

2017 ◽  
Vol 17 (43) ◽  
pp. 23-27
Author(s):  
Tumendelger A ◽  
Byambadorj T ◽  
C Bors ◽  
A Lorke
Keyword(s):  
Wastewater Treatment ◽  
Inorganic Nitrogen ◽  
Stratospheric Ozone ◽  
Treatment Plant ◽  
Nitrifying Bacteria ◽  
Aeration Tank ◽  
Site Preference ◽  
N2o Production ◽  
Biological Reaction ◽  
No2 Reduction

Nitrous oxide (N2O) is an increasing greenhouse gas in the troposphere and a potential destroyer of stratospheric ozone layer. Wastewater treatment plant (WWTP) is one of the anthropogenic N2O sources because inorganic and organic nitrogen compounds are converted to nitrate (NO3-, in the case of standard system) or N2 (in the case of advanced system) by bacterial nitrification and denitrifcation processes in WWTP. These major processes can be distinguished by isotopocule analysis. In order to reveal production mechanisms of N2O in a standard wastewater treatment, we made water sampling at the central WWTP in Ulaanbaatar. The water samples collected from seven stations including biological reaction tanks were measured for concentration and isotopocule ratios of dissolved N2O and other inorganic nitrogen. Dissolved N2O concentration was extremely higher than that expected under atmospheric equilibrium (about 9 nmol/l) at all stations, indicating that this system is a potential source of N2O. It showed a gradual increase with the progress of biological reaction and the highest concentration (335.7 nmol/l) was observed at station N5-4 of the aeration tank when the DO was 5.7 mg/l. Nitrification by nitrifying bacteria could actively occur by the concentration of NH4+ decreased whereas NO2- and NO3- showed a temporal and monotonic increase, respectively, under high DO concentration. Although the reported values of site preference (SP) of N2O, the difference in 15N/14N ratio between central (α) and terminal (β) nitrogen, produced via NO2- reduction (SP(ND)), including both nitrifier and denitrifier denitrification, and NH2OH oxidation (SP(HO)) ranged from -10.7‰ to 0‰ and 31.4‰ to 36.3‰, respectively, the observed SP at aeration tank was close to SP(ND) rather than SP(HO). It was ranged from 0.4‰ to 13.3‰ when N2O concentration was high, implying that the NO2- reduction made a greater contribution to N2O production. Slightly elevated SP (13.3‰) only at station N5-1 was derived from the mixing of N2O produced via NH2OH oxidation and the maximal contribution of this pathway was estimated to be about 40%. In other words, the contribution of NO2- reduction was more than 60%.

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