Effect Of Ammonium Concentration Research Articles

Towards in-site carbon utilization and highly efficient nutrients removal: Effects of ammonium on the phosphorus recovery performance in a biofilm-based system

An alternatively anaerobic–aerobic biofilm system was operated for treating synthetic municipal wastewater for 150 days, and the effect of ammonium concentration in range of 15 mg∙L−1 - 50 mg∙L−1 on the phosphorus recovery performance was discussed. The ammonium concentration was confirmed as an important factor for balancing phosphorus accumulating organisms (PAOs) and denitrifying phosphorus-accumulating organisms (DPAOs) to affect nutrients removal and phosphorus recovery. The PAOs dominated in phosphorus removal with the ammonium less than 30 mg∙L−1, the ortho-P concentration in recovery steam was plateaued at 52 mg∙L−1. The increase in ammonium to 40 mg∙L−1 caused the seriously deterioration in PAOs activity; however, the phosphorus removal and recovery performance was decreased slightly which attributed to the vital contribution of DPAOs in phosphorus removal. The adverse effect of ammonium can be eliminated by decreasing the volume exchange ratio (VER) from 3.0 to 1.5, leading to the phosphorus concentration in recovery steam of 72.21 mg∙L−1. Meanwhile, the phosphorus removal efficiency (PRE) and total nitrogen removal efficiency (NRE) were stable at 97.8 % and 99.2 %, respectively, indicating highly efficient phosphorus recovery and nutrients removal in the biofilm system. The outcome of the present study could facilitate the establishment of an integrative technology to realize in-site carbon utilization, highly efficient nutrients removal and phosphorus recovery simultaneously in the mainstream treatment of sewage wastewater, and the study reveals the transformation pathways of P and N in the BPRR system, as well as the complex interactions between functional microorganisms.

Effects of ammonium concentration in the catholyte on electricity and algal biomass generation in a photosynthetic microbial fuel cell treating wastewater

In this study, algal cathodic compartments were integrated to generate oxygen in microbial fuel cells. Chlorella vulgaris and Scenedesmus quadricauda were grown under three NH4+–N concentrations (50, 300, and 900 mg L−1) in the catholyte. With 50 mg L−1 of NH4+–N, the highest maximum power densities of 16.72 and 5.96 mW m−2 were obtained with Chlorella vulgaris and Scenedesmus quadricauda, respectively. Under this condition, dissolved oxygen reached 19.27 and 9.87 mg L−1 for Chlorella vulgaris and Scenedesmus quadricauda respectively, along with 100% removal of NH4+–N within 210 h. Both cultures showed inhibition under higher concentrations of NH4+–N, resulting in decreased photoautotrophic growth that generates oxygen for the cathodic reaction. Under all concentrations, Chlorella vulgaris displayed better tolerance to ammonium. From the results, it can be summarized that 50 mg L−1 of NH4+–N in wastewater is suitable as a microalgal cultivation medium in a cathodic compartment.

Effect of ammonium concentration on structural, optical and morphological properties of H-Nb2O5 thin films—A novel study

Effect of ammonium concentration on optical, structural and surface roughness properties of Nb2O5 thin films is conducted in this work. Estimated optical band gap and optical constant confirm the dependency of Nb2O5 thin films on ammonium molarity. The band gap in the range of 3.3 to 4.7 eV is directly related to the solution properties. The structural properties are recorded by x-ray diffraction method that display the formation of monoclinic niobium pentoxide (H-Nb2O5) thin films. Optimum molarity at 12 M reveals the prime ammonium concentration for the Nb2O5 thin films formation. The energy gap at optimum preparation state ensures the development of semiconducting material that suits solar cell and other optoelectronics application. AFM results show a highly uniform surface. Grain size is observed to increase with ammonium concentration and recorded to reach its maximum of 85.28 nm at 12 M.

Cultivation of Chlorella vulgaris in manure-free piggery wastewater with high-strength ammonium for nutrients removal and biomass production: Effect of ammonium concentration, carbon/nitrogen ratio and pH

Ammonia toxicity is a major disadvantage of microalgal growth when high-strength ammonium wastewaters like manure-free piggery wastewater (MFPW) were used as microalgal growth medium. In the present study, the effect of ammonium concentration, carbon/nitrogen ratio, and pH on ammonia toxicity of Chlorella vulgaris cultivated in the MFPW and nutrients removal was investigated. The three important parameters affected ammonia toxicity of C. vulgaris and nutrients removal of the MFPW significantly. The ammonium concentration of the MFPW could be decreased by air stripping. Microalga grew best at a carbon/nitrogen ratio of 25:1 with the maximum biomass concentration of 3.83 g L−1, the highest cell viability of 97%, and the removal of 100% ammonia, 95% of total phosphorus, and 99% of chemical oxygen demand. Ammonia toxicity was alleviated by pH control. The application of the established strategies can enhance nutrients removal of the MFPW while mitigating ammonia toxicity of C. vulgaris.

Ammonium removal using algae-bacteria consortia: the effect of ammonium concentration, algae biomass, and light.

In this study, the effects of ammonium nitrogen concentration, algae biomass concentration, and light conditions (wavelength and intensity) on the ammonium removal efficiency of algae-bacteria consortia from wastewater were investigated. The results indicated that ammonium concentration and light intensity had a significant impact on nitrification. It was found that the highest ammonia concentration (430mgN/L) in the influent resulted in the highest ammonia removal rate of 108±3.6 mgN/L/days, which was two times higher than the influent with low ammonia concentration (40mgN/L). At the lowest light intensity of 1000 Lux, algae biomass concentration, light wavelength, and light cycle did not show a significant effect on the performance of algal-bacterial consortium. Furthermore, the ammonia removal rate was approximately 83±1.0mgN/L/days, which was up to 40% faster than at the light intensity of 2500 Lux. It was concluded that the algae-bacteria consortia can effectively remove nitrogen from wastewater and the removal performance can be stabilized and enhanced using the low light intensity of 1000 Lux that is also a cost-effective strategy.

Leaching hydrodynamics of weathered elution-deposited rare earth ore with ammonium salts solution

In order to reveal the permeability rule of leaching agent solution and the effects of anions in the leaching process of weathered crust elution-deposited rare earth (RE) ores, the effects of ammonium concentration, temperature, particle size and porosity on the permeability were discussed in detail with (NH4)2SO4, NH4Cl and NH4NO3 as the leaching agent. It was found that the permeation velocity of ammonium salts increased linearly with the increase of hydraulic gradient. The seepage of ammonium salts solution in the RE ores followed Darcy's law and displayed a laminar flow. The properties of the leaching agent solution and RE ores were the main factors that affect the permeability of RE ores. With the decrease of ammonium concentration and increase of temperature, the viscosity of solution decreased and the permeability coefficients of RE ores increased. And the effects of temperature on the viscosity and permeability were larger than ammonium concentration. The permeability of RE ores became worse with the decrease of particle size and porosity, and the particle size played a more important role compared with porosity. The permeability coefficient of RE ores increased and the viscosity of ammonium salts solution decreased in the order of (NH4)2SO4, NH4Cl and NH4NO3, implying that the penetrating power of anions increased in the order of SO42–, Cl− and NO3−. The results may play a vital role in improving the permeability of weathered crust elution-deposited RE ores.

Effect of Ammonium Concentration on N2O Emission During Autotrophic Nitritation Under Oxygen-Limited Conditions

Abstract Nitrous oxide (N2O) is one of the most powerful greenhouse gases, emitted by ammonia-oxidizing bacteria (AOB) and denitrifier during nitrogen transformation. A laboratory-scale sequencing batch reactor with enriched nitrifiers was developed under oxygen-limited conditions with synthetic wastewater (without organic carbon) to investigate the effect of ammonium (NH4+) concentration on N2O emission. The system achieved 70% conversion of the influent NH4+ to nitrite (NO2−) and the N2O emission factor (ratio between N2O nitrogen emitted and the NH4+ oxidized) was about 17.0%. NH4+ concentration was shown to have a major impact on N2O emission. When influent NH4+ concentrations were 60, 120, and 240 mg·N/L, total N2O emissions were 3.24, 8.75, and 24.59 mg·N/L, respectively. Comprehensive analysis of N2O emission rate on NO2− concentration (Fig. 5) together with the absence of a contribution from heterotrophic denitrifiers suggests that AOB denitrification is the main cause of N2O emission during oxyge...

Effect of Ammonium Concentration on the Emission of N2O Under Oxygen-Limited Autotrophic Wastewater Nitrification

A significant amount of nitrous oxide (N(2)O), which is one of the serious greenhouse gases, is emitted from nitrification and denitrification of wastewater. Batch wastewater nitrifications with enriched nitrifiers were carried out under oxygen-limited condition with synthetic (without organic carbon) and real wastewater (with organic carbon) in order to find out the effect of ammonium concentration on N(2)O emission. Cumulated N(2)O-N emission reached 3.0, 5.7, 6.2, and 13.5 mg from 0.4 l of the synthetic wastewater with 50, 100, 200, and 500 mg/l NH(4)(+)-N, respectively, and 1.0 mg from the real wastewater with 125 mg/l NH(4)(+)-N. The results indicate that N(2)O emission increased with ammonium concentration and the load. The ammonium removal rate and nitrite concentration also increased N(2)O emission. Comparative analysis of N(2)O emission from synthetic and real wastewaters revealed that wastewater nitrification under oxygen-limited condition emitted more N(2)O than that of heterotrophic denitrification. Summarizing the results, it can be concluded that denitrification by autotrophic nitrifiers contributes significantly to the N(2)O emission from wastewater nitrification.

Effect of ammonium concentration on microbial population and performance of a biofilter treating air polluted with methane

The effect of ammonium concentration on the microbial population and performance of a biofilter operated at methane concentrations of 0.3% (v/v) was studied. In a range of ammonium concentration from 0.05 to 0.5 gN-NH 4 +/L, the removal efficiency, carbon dioxide production rate, biomass production, ammonium conversion and nitrate production rate were determined. The middle biofilter section microbial population was analyzed using denaturing gradient gel electrophoresis (DGGE). DNA sequence analysis revealed that the bacteria colonizing the middle biofilter section belonged essentially to 4 physiological groups: methanotrophs, methylotrophs, nitrifying and denitrifying bacteria. Ammonium concentration affected the presence of bacteria from each group and the interactions among them defined the biofilter performance. In the range of ammonium concentrations tested, the methane removal efficiency decreased from 70 to 13%, the carbon dioxide production rate from 25 to 7.5 g/(m 3 h), and the mean of dry biomass content in the packed bed from 12.8 to 6.7 g biomass/kg filter bed. The nitrate production rate increased with ammonium concentration; however, it presented negative values at nitrate concentrations around 0.5 gN/L. This suggests that denitrification occurred due to favourable conditions for the growth of denitrifiers. An analysis of methane biodegradation at different layers of the biofilter shows that the methanotrophic and nitrifying activities were more important in the upper section of the biofilter.

Effects of ammonium concentration and charge exchange on ammonium recovery from high strength wastewater using a microbial fuel cell

Ammonium recovery using a two chamber microbial fuel cell (MFC) was investigated at high ammonium concentration. Increasing the ammonium concentration (from 0.07 to 4 g ammonium–nitrogen/L) by addition of ammonium chloride did not affect the performance of the MFC. The obtained current densities by DC-voltammetry were higher than 6 A/m 2 for both operated MFCs. Also continuous operation at lower external resistance (250 Ω) showed an increased current density (0.9 A/m 2). Effective ammonium recovery can be achieved by migrational ion flux through the cation exchange membrane to the cathode chamber, driven by the electron production from degradation of organic substrate. The charge transport was proportional to the concentration of ions. Nonetheless, a concentration gradient will influence the charge transport. Furthermore, a charge exchange process can influence the charge transport and therefore the recovery of specific ions.

Effect of ammonium concentration on protein and chlorophyll contents and the number of ribosomes in the cells of soybean mixotrophic callus

The effects of exogenous ammonium concentrations on the contents of protein and chlorophyll and also the number of ribosomes in the cells of the mixotrophic callus of soybean (Glycine max L.) were studied. The curves of protein and chlorophyll contents differed at ammonium concentrations exceeded 20 mM. An increase in the content of protein and chlorophyll was observed in the range of ammonium concentrations between 2 and 10 mM. At lower concentrations, their contents were equal to control values. In the absence of ammonium from the nutrient medium, the number of ribosomes in the cells was low. The presence of ammonium in medium (0.01–20.0 mM) induced a manifold increase in the number of ribosomes, which did not depend on the ammonium concentration. It is supposed that ammonium is a factor controlling the formation and functioning of the protein-synthesizing machinery; its indirect effect on the content of the green pigment in chloroplasts of the mixotrophic callus cells is also discussed.

Effect of ammonium concentration on alcoholic fermentation kinetics by wine yeasts for high sugar content

Kinetics of alcoholic fermentation by Saccharomyces cerevisiae wine strains in a synthetic medium with high sugar content were established for different nitrogen initial content and are presented for four strains. The composition of the medium was close to grape must except that the nitrogen source consisted mainly in ammonium and was varied from 120 to 290 mg N/l assimilable nitrogen. The overall nitrogen consumed was also estimated in order to determine nitrogen requirement variability. The effect of assimilable nitrogen was in general greater on sugar consumption rates than on growth and three kinds of effect on sugar consumption rates were observed: (i) existence of an optimal initial nitrogen level for a maximal sugar consumption rate (inhibition if excess), (ii) no effect of nitrogen beyond the intermediary level (saturation), (iii) sugar consumption rate proportional to the initial nitrogen level (activation). In all cases, the amount of consumed nitrogen increased with its initial concentration and so did the fructophilic capacity of the strains. The optimal requirement varied from 0.62 to 0.91 mg N/g of sugars according to different strains. There was no general correlation between the sugar assimilation rates and the nitrogen requirement.

Availability of ammonium influences photosynthesis and the accumulation of mycosporine-like amino acids in two Porphyra species (Bangiales, Rhodophyta)

The effect of ammonium concentration on photosynthetic activity estimated as in vivo chlorophyll fluorescence, i.e. maximal quantum yield (Fv/Fm) and electron transport rate (ETR) and on the accumulation of mycosporine-like amino acids (MAAs), chlorophyll a (chl a), biliproteins (BP) and soluble proteins (SP) in the red algae Porphyra leucosticta Thuret in Le Jolis collected from Lagos (Malaga, Spain) and Porphyra umbilicalis (Linnaeus) J. Agardh from Helgoland (Germany) was evaluated. Discs of both species were incubated with three ammonium concentrations (0, 100 and 300 µM) under artificial PAR and UV radiation for 7 days. Photosynthetic activity decreased under the culture conditions due to UV radiation and ammonium availability. The decrease of both Fv/Fm and maximal ETR was related to ammonium supply, i.e. the lowest decrease occurred in algae growing with the highest concentration of ammonium. In both species, after 7 days of culture, the content of chl a, BP and SP was higher under 300 µM than that under 0 and 100 µM ammonium. In both species, the content of MAAs was increased under 300 µM ammonium compared to the initial value, whereas a decrease under 0 and 100 µM ammonium was observed only in P. leucosticta. The content of MAAs in P. umbilicalis did not present significant differences compared to the initial value, probably because of the high initial content of MAAs. In both Porphyra species, four MAAs were identified: shinorine, porphyra-334, palythine and asterina-330. However, P. leucosticta modified its MAA pattern during the incubation time, reaching the same percentages found for P. umbilicalis, which did not show any change during the experimental period. P. leucosticta exhibited a decrease in BP/SP and BP/chl a ratios through the incubation time and an increase in MAAs/BP. The ratio MAAs/chl a did not show any variation with time or treatment, as was also true for all ratios in P. umbilicalis. In summary, ammonium supply diminished the decrease of Fv/Fm, increased the content of photosynthetic pigments (chlorophyll and biliprotein) and soluble protein, and stimulated of the accumulation of MAAs in the red algae P. leucosticta and P. umbilicalis.

78 A comparison of four native Porphyra species from coastal new england in response to ammonium and temperature in small tank system

Porphyra is one of the world's most valued maricultured seaweeds. The effects of ammonium concentration and temperature on growth and tissue nitrogen content of Porphyra from coastal New England were studied in 50 liter tanks to produce critical information for the development of a land based aquaculture system. Four Northwest Atlantic Porphyra species: P. leucosticta, P. amplissima, P. linearis and P. umbilicalis, were cultivated for two to three weeks at saturating light intensities (100–150?Em‐2s‐1) and six combinations of ammonium (25 and 250?M) and temperature: 10, 15 and 20?C. The specific growth rate (SGR) of all species under most temperature conditions was significantly higher at 250?M than at 25?M ammonium. P. leucosticta showed higher growth rate at 10 and 15?C (10%d‐1 at 250?M versus 9 – 9.5%d‐1 at 25?M) in the first week. The SGRs of P. linearis in the second week and P. umbilicalis in the first week were the highest at 10?C (16 and 10%d‐1 at 250?M versus 12 and 8%d‐1 at 25?M, respectively). The SGR decreased with increasing temperature. In contrast, P. amplissima showed the highest SGR at 20?C (9%d‐1 at 250?M versus 7%d‐1 at 25?M) in the first week, and the SGR decreased at lower temperatures. Nitrogen concentration in tissue of P. leucosticta was significantly higher at 250?M than at 25?M. The rapid nutrient assimilation and fast growing ability makes Porphyra an excellent candidate for bioremediation and integrated aquaculture.

Effect of Ammonium Concentration on N 2 O Release and on the Community Structure of Ammonia Oxidizers and Denitrifiers

Effect of Ammonium Concentration on N ₂ O Release and on the Community Structure of Ammonia Oxidizers and Denitrifiers

Effect of Ammonium Concentration on SO2 Absorption in a Wet Limestone Gypsum FGD Process.

To investigate the effect of the ammonium concentration on SO2 absorption with a chemical reaction in the wet limestone-gypsum flue gas desulfurization (FGD) process, the SO2 absorption rate in limestone slurry was studied by using a stirred tank reactor at a constant pH, high temperature (50°C) and under the presence of ammonium. An absorption model with a reaction plane and the presence of ammonium in the liquid based on the film model was also proposed for an actual FGD plant.For the SO2 absorption rate depending on the concentration of ammonium, the experimental values agreed quite well with the results calculated with the absorption model, taking the presence of ammonium in the liquid into consideration.

Effect of ammonium ions on delta 5,7-sterol synthesis in Saccharomyces cerevisiae.

The effect of ammonium concentration in the medium on delta 5,7-sterol synthesis was examined. Higher concentrations of this nitrogen source in the medium decreased sterol synthesis and accumulation during growth. An intermittent supply with ammonium resulted in a proportional synthesis of delta 5,7-sterols and biomass. The carbon to nitrogen molar ratio of greater than or equal to 40 allowed the maximum accumulation of delta 5,7-sterols with our strain of baker's yeast.

Effect of ammonium concentration on growth and nitrogen accumulation by soybean grown in nutrient solution

Soybean (Glycine max (L.) MERR. CV. ‘Amsoy’) plants were grown for 40 days in nutrient solution at various concentrations of ammonium. Maximum yield of dry matter was obtained at a concentration of 715 μM. Further increase in the concentration of ammonium resulted in a reduction in growth due to ammonium toxicity which affected both root and shoot development. The pattern of nitrogen accumulation in tops was consistent with the multiphasic uptake of ammonium and can be represented by 2 phases in the range 1.78 X 10-5-3.57 x X 10-3 M of ammonium.