Enrichment of Denitrifying Bacterial Community Using Nitrite As an Electron Acceptor for Nitrogen Removal from Wastewater
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Chapter 7.1 Nitrogen Dioxide
Chapter 7.1 Nitrogen dioxide General description Many chemical species of nitrogen oxides (NOx) exist, but the air pollutant species of most interest from the point of view of human health is nitrogen dioxide (NO2). Nitrogen dioxide is soluble in water, reddish-brown in colour, and a strong oxidant. Nitrogen dioxide is an important atmospheric trace gas, not only because of its health effects but also because (a) it absorbs visible solar radiation and contributes to impaired atmospheric visibility; (b) as an absorber of visible radiation it could have a potential direct role in global climate change if its concentrations were to become high enough; (c) it is, along with nitric oxide (NO), a chief regulator of the oxidizing capacity of the free troposphere by controlling the build-up and fate of radical species, including hydroxyl radicals; and (d) it plays a critical role in determining ozone (O3) concentrations in the troposphere because the photolysis of nitrogen dioxide is the only key initiator of the photochemical formation of ozone, whether in polluted or unpolluted atmospheres (1, 2). Sources On a global scale, emissions of nitrogen oxides from natural sources far outweigh those generated by human activities. Natural sources include intrusion of stratospheric nitrogen oxides, bacterial and volcanic action, and lightning. Because natural emissions are distributed over the entire surface of the earth, however, the resulting background atmospheric concentrations are very small. The major source of anthropogenic emissions of nitrogen oxides into the atmosphere is the combustion of fossil fuels in stationary sources (heating, power generation) and in motor vehicles (internal combustion engines). -
The Formation, Effects and Control of Oxides of Nitrogen in Diesel Engines
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 13, Number 6 (2018) pp. 3200-3209 © Research India Publications. http://www.ripublication.com The Formation, Effects and Control of Oxides of Nitrogen in Diesel Engines Maroa Semakula1and Prof Freddie Inambao2 1,2University of Kwazulu-Natal Durban South-Africa. Abstract HPL High Pressure Loop EGR The transport service industry is a heavy user of diesel IDICI Indirect Injection Compression Ignition propelled engines as prime movers of goods and services. The diesel propelled engine is praised due to its high fuel efficiency, L Length or Piston Stroke reliability and durability. However, the nitrogen emissions as a result of diesel fuel combustion characteristics raise major LPL Low Pressure Loop EGR concerns for the manufacturing industry, environmentalists and health care researchers. The manner in which diesel engines M Organic Residue combust their fuel is the main cause of the nitrogen oxide NG Natural Gas emission proportion. Although there are other sources of nitrogen oxide emission, this work will cover the sources of NO Nitrogen Oxide nitrogen oxides and their formation within the diesel engine, their routes of formation, identify the mechanisms under which NOX Oxides of Nitrogen Excluding Nitrogen Trioxide the formations occur, identify their types and interactions, look Up at the various effects of the oxides of nitrogen on human health and the overall damage to the natural environment, and look OH Water or Hydroxide Radical critically at control systems. -
Nitrogen Oxide - Wikipedia, the Free Encyclopedia Page 1 of 3
Nitrogen oxide - Wikipedia, the free encyclopedia Page 1 of 3 Nitrogen oxide From Wikipedia, the free encyclopedia Nitrogen oxide can refer to a binary compound of oxygen and nitrogen, or a mixture of such compounds: Contents ■ Nitric oxide (NO), nitrogen(II) oxide ■ Nitrogen dioxide (NO2), nitrogen(IV) oxide ■ 1 NOx ■ Nitrous oxide (N2O), nitrogen(I) oxide ■ 2 Derivatives ■ Nitrate radical (NO3), nitrogen(VI) oxide ■ 3 See also ■ Dinitrogen trioxide (N2O3), nitrogen(II,IV) oxide ■ 4 References ■ Dinitrogen tetroxide (N2O4), nitrogen(IV) oxide ■ Dinitrogen pentoxide (N2O5), nitrogen(V) oxide In atmospheric chemistry and air pollution and related fields, nitrogen oxides refers specifically to NOx [1][2] (NO and NO2). Only the first three of these compounds can be isolated at room temperature. N2O3, N2O4, and N2O5 all decompose rapidly at room temperature. Nitrate radical is very reactive. N2O is stable and rather unreactive at room temperature, while NO and NO2 are quite reactive but nevertheless quite stable when isolated. Dinitrogen trioxide, Nitric oxide, NO Nitrogen dioxide, NO2 Nitrous oxide, N2O N2O3 Dinitrogen tetroxide, Dinitrogen pentoxide, N2O4 N2O5 http://en.wikipedia.org/wiki/Nitrogen_oxide 11/2/2010 Nitrogen oxide - Wikipedia, the free encyclopedia Page 2 of 3 NOx Main article: NOx NOx (often written NOx) refers to NO and NO2. They are produced during combustion, especially at high temperature. These two chemicals are important trace species in Earth's atmosphere. In the troposphere, during daylight, NO reacts with partly oxidized organic species (or the peroxy radical) to form NO2, which is then photolyzed by sunlight to reform NO: NO + CH3O2 → NO2 + CH3O NO2 + sunlight → NO + O The oxygen atom formed in the second reaction then goes on to form ozone; this series of reactions is the main source of tropospheric ozone. -
Nitrogen Oxides
Pollution Prevention and Abatement Handbook WORLD BANK GROUP Effective July 1998 Nitrogen Oxides Nitrogen oxides (NOx) in the ambient air consist 1994). The United States generates about 20 mil- primarily of nitric oxide (NO) and nitrogen di- lion metric tons of nitrogen oxides per year, about oxide (NO2). These two forms of gaseous nitro- 40% of which is emitted from mobile sources. Of gen oxides are significant pollutants of the lower the 11 million to 12 million metric tons of nitrogen atmosphere. Another form, nitrous oxide (N2O), oxides that originate from stationary sources, is a greenhouse gas. At the point of discharge about 30% is the result of fuel combustion in large from man-made sources, nitric oxide, a colorless, industrial furnaces and 70% is from electric utility tasteless gas, is the predominant form of nitro- furnaces (Cooper and Alley 1986). gen oxide. Nitric oxide is readily converted to the much more harmful nitrogen dioxide by Occurrence in Air and Routes of Exposure chemical reaction with ozone present in the at- mosphere. Nitrogen dioxide is a yellowish-or- Annual mean concentrations of nitrogen dioxide ange to reddish-brown gas with a pungent, in urban areas throughout the world are in the irritating odor, and it is a strong oxidant. A por- range of 20–90 micrograms per cubic meter (µg/ tion of nitrogen dioxide in the atmosphere is con- m3). Maximum half-hour values and maximum 24- verted to nitric acid (HNO3) and ammonium hour values of nitrogen dioxide can approach 850 salts. Nitrate aerosol (acid aerosol) is removed µg/m3 and 400 µg/m3, respectively. -
Aqueous Catalytic Disproportionation and Oxidation of Nitric Oxide
Environ. Sci. Technol. 1998, 32, 876-881 Noncatalytic oxidation/reduction and absorption tech- Aqueous Catalytic niques (chemical scrubbing) have the advantage of being able to eliminate both NOx and SOx simultaneously (5, 6). Disproportionation and Oxidation of The primary impediment to their industrial application has Nitric Oxide been the low solubility of NO in aqueous solution. Because nitric oxide is 90-95% of the NOx present in typical flue gas streams (7), it has been necessary to preoxidize NO to NO2 JOSEPH H. MACNEIL, before the scrubber. Direct oxidation with O occurs slowly POLLY A. BERSETH, 2 at the low NO concentrations present in exhaust streams. GLENN WESTWOOD, AND The additional complexity and expense of using alternative WILLIAM C. TROGLER* - oxidants, such as OCl and H2O2, have prevented widespread Department of Chemistry and Biochemistry, University of use of this method. Other approaches to treating NO in California at San Diego, La Jolla, California 92093-0358 aqueous scrubbers have included the addition of heavy metal chelators to sequester nitric oxide for subsequent removal (8) and even the addition of yellow phosphorus emulsions Nitric oxide, a byproduct of combustion exhaust, is a key and O2 to oxidize nitric oxide to a combination of nitrite and nitrate salts (9). species that leads to urban photochemical smog. Nitric oxide exhibits low aqueous solubility, and it has proved In this paper we report a novel catalytic approach for difficult to remove NO from gas streams by aqueous scrubbing removing NO in aqueous solution with supported palladium or platinum metal. The catalysts display activity at ambient methods. -
Chapter 10 Acronyms.Pdf
10. Acronyms °C Degrees Celsius (Centigrade) µm Micrometer (micron) 1D One dimensional 3D Three dimensional 3GAHHS Third-generation advanced high-strength steels A Ampere A/C Air conditioning ABR Advanced Battery Research AC Alternating current ACE Advanced Combustion Engines (VTO program) ACEC Advanced Combustion and Emissions Control ACI Advanced compression ignition ADAS Advanced Driver Assistance Systems ADP Advanced drying process AEC Advanced engine combustion AEC Automotive Electronics Council AEV All-electric vehicle AFDC Alternative Fuels Data Center AFV Alternative fuel vehicle Ag Silver Ah Ampere-hour AHHS Advanced high-strength steels AIM Accelerated insertion of materials AKI Anti-knock index Al Aluminum ALD Atomic layer deposition AlF3 Aluminum fluoride AlNiCo Aluminum-nickel-cobalt AMR Annual Merit Review AMT Air maintenance technology AMT Automated manual transmission ANL Argonne National Laboratory APEEM Advanced Power Electronics and Electric Motors API American Petroleum Institute API Application programming interface APS Advanced photon source APTA American Public Transportation Association ARA Automotive Recyclers Association ARC Affordable Rankine cycle ARK Abuse reaction kinetics ARL Army Research Laboratory Acronyms 10-1 2016 ANNUAL MERIT REVIEW, VEHICLE TECHNOLOGIES OFFICE ARPA-E Advanced Research Projects Agency - Energy ASCR Advanced scientific computing research ASI Area specific impedance ASSERT Analysis of Sustainability, Scale, Economics, Risk, and Trade ASTM American Society for Testing and Materials ATF -
Kinetics of Nitrogen Oxide Reduction by Means of Ammonia on a Polish Carbon Sorbent
Polish Journal of Environmental Studies Vol. 11, No. 6 (2002), 689-693 Kinetics of Nitrogen Oxide Reduction by Means of Ammonia on a Polish Carbon Sorbent K. Jastrz¹b*, J. Szarawara aculty of Chemistry, Silesian University of Technology, 44-100 Gliwice, B. Krzywoustego Str. 6, Poland, Received: 16 January, 2002 Accepted: 13 May, 2002 Abstract This paper studies nitrogen oxide reduction by means of ammonia in a flow reactor with a fixed bed of the Polish carbon sorbent AKP-5. The kinetic curves â(t), showing the dependence of the degree of reduction of nitrogen oxide on time have been determined for four inlet NO concentrations. On the basis of the degree of NO reduction determined for the steady state conditions, a simplified model of the kinetic equation has been developed and verified. The results obtained are very important for environmental protection. Keywords: nitrogen oxides, carbon sorbent, selective catalytic reduction, kinetics of reaction Introduction of reactants), the physical adsorption and chemisorption of the substrates on the surface, and a series of catalytic surface The process based on the use of specially prepared reactions. Moreover, the process occurs according to carbon sorbents (so-called active cokes) is an interesting a complex chemical mechanism [7]. In the case of the SCR modification of the selective catalytic reduction (SCR) process, the reduction of NO by ammonia is most often x method. In this process the sorbent plays a double role: described by the following overall equation: it is both an adsorbent of nitrogen oxides and a classical catalyst of NO reduction. An advantage of this method is 4 NO + 4 NH + O = 4 N + 6 H O (1) x 3 2 2 2 the low temperature of the process (100 ÷ 170°C). -
Nitrogen Oxide Emissions from Air Traffic
TECHNOLOGIE 369 CHIMIA 44 (1990) Nr. II (November) Chimia 44 (1990) 369-371 ~'1Schwei=. Chemiker-Verband; ISSN 0009-4293 Nitrogen Oxide Emissions from Air Traffic Robert A. Egli* Rober! A. Eg/i: Born 1926 in Rheineck, Switzer- land. After completing his chemistry education at the HTL Winterthur (1948), he worked for 10years as a group leader in an organic synthesis laboratory for Ci/og AG in Schaffhausen, later as head of the Ahstract. About 153 million metric tons of aviation fuel were consumed in 1987, which analytical development laboratory, and in addition was ca. ]3% of the world's consumption of transportation fuel. Burning this fuel to this job. for 13 years quality control director of Ci/ag AG. From 1985 to 1989, he was responsible produced ca. 2.75 million tons of nitrogen oxides, calculated as N0 , using an average 2 for patents, library, and literature searches. He emission index £1 of 18 g N02 per kg fuel. 0.92 million tons of N02 was exhausted published 17 papers, mainly in the field of organic between 9 and 13 km, which is an especially endangered altitude range, estimated with an analytical chemistry. Since January 1990, Egli is £f of 15 g N02 per kg fuel. Air traffic is the main NO, source between 9 and 13 km. Since working as an independent consultant. For many the NO, background concentration at this altitude is low and the possible lifetime of an years, his special interests have been air pollution problems and climatology. admixture two orders of magnitude larger compared to the ground, these NO .•emissions can lead to an important increase of tropospheric ozone, which contributes to the g]obal greenhouse warming. -
Isolation and Identification of Denitrifying Bacteria and Its Growth and Metabolism Characteristics
2017 2nd International Conference on Environmental Science and Energy Engineering (ICESEE 2017) ISBN: 978-1-60595-417-2 Isolation and Identification of Denitrifying Bacteria and Its Growth and Metabolism Characteristics Xin-ran JIANG, Dian JIAO, Lei ZHANG and Li-na ZHENG College of Marine Technology and Environmental, Dalian Ocean University, Dalian 116023, China Keywords: Denitrification, Nitrate, Isolation and identification, Activity research. Abstract. A denitrifying bacterium DN20 was isolated from the biofilm after centrifugation in the aquaculture purification system of a aquaculture base, and the denitrification characteristics of the strain were further studied. The strain was identified by 16S rDNA sequence analysis, the effects of temperature, salinity, pH, substrate concentration and C/N ratio on denitrification activity were studied. Introduction Denitrifying bacteria are a kind of bacteria that can cause denitrification. Biological denitrification is the use of denitrifying bacteria, nitrate nitrogen into gaseous products to remove, is considered to be the most economical and effective way of nitrogen removal [1]-[2]. The application of denitrifying bacteria and the removal of nitrate in water have become the research focus[3]-[5], many methods have been reported [6]-[8]. In recent years, some studies on salt tolerant and halophilic denitrifying bacteria have been reported abroad [9]-[10]. In this study, the sludge from the culture pond was taken as the main separation source, and the enrichment, separation and purification were carried out.To obtain a highly efficient nitrate removal ability of denitrifying bacteria, named strain DN20. The aim of this study is to provide effective bacteria source for practical application of nitrate-N treatment in aquaculture water. -
Bacteria and Cyanobacteria
Bacteria and Cyanobacteria Bacteria represent an amazingly diverse group of organisms that are of great ecological, economic, agricultural, and medical importance. Cyanobacteria, also known as blue-green bacteria, contain thylakoid membranes with photosynthetic pigments (chlorophyll a and phycobilins) and are capable to oxygenic photosynthesis. Purple bacteria and green sulfur bacteria occupy habitats in the presence of hydrogen sulfide and oxidize and release sulfur gas rather than oxygen. Nitrogen fixing and denitrifying bacteria have an exceptionally important role in nitrogen cycling in terrestrial plant communities. Many vascular plants such as legumes and an aquatic fern have a symbiotic relationship with nitrogen fixing bacteria. Bacteria are also important carbon recyclers in the environment by assisting in the decomposition of dead organisms. Bacteria are considered Prokaryotes (before the nucleus) and represent a lineage that is ancient and possess a number of novel features. Bacteria generally lack internal compartmentalized organelles that are bound by membranes. Organelles such as Golgi bodies (dictyosomes), chloroplasts, mitochondria, and nuclei are regarded as unique to Eukaryotic (true nucleus) organisms. Recently, evolutionary biologists have determined that two major kingdoms of bacteria are present on the planet. Eubacteria represent the true bacteria and contain many of the groups that we are most familiar with such as cyanobacteria. E. coli, Streptococcus, and Rhizobium. Archaebacteria represent an ancient lineage whose members occupy rather inhospitable habitats such as deep sea thermal vents and miles deep in the Earth=s crust, but are also found in more normal environments. The objective of this lab is to examine the morphology, structure, and ecology of bacteria and cyanobacteria. -
Isolation and Characterization of a Novel Denitrifying Bacterium with High Nitrate Removal: Pseudomonas Stutzeri
Iran. J. Environ. Health. Sci. Eng., 2010, Vol. 7, No. 4, pp. 313-318 ISOLATION AND CHARACTERIZATION OF A NOVEL DENITRIFYING BACTERIUM WITH HIGH NITRATE REMOVAL: PSEUDOMONAS STUTZERI *1A. Rezaee, 2H. Godini, 1S. Dehestani, 1S. Kaviani 1 Department of Environmental Health, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran 2 Department of Environmental Health, School of Public Health, Lorestan University of Medical Sciences, Khoramabbad, Iran Received 16 August 2009; revised 13 Jully 2010; accepted 20 August 2010 ABSTRACT The aim of this study was to isolate and characterize a high efficiency denitrifier bacterium for reducing nitrate in wastewater. Six denitrifier bacteria with nitrate removal activities were isolated from a petrochemical industry effluent with high salinity and high nitrogen concentrations without treatment. The isolated bacteria were tested for nitrate reomoval activity. One of the bacterium displayed the highest reduction of nitrate. The strain was preliminarily identified using biochemical tests and further identified based on similarity of PCR-16S rRNA using universal primers. Biochemical and molecular experiments showed that the best bacterium with high nitrate removal potential was Pseudomonas stutzeri, a member of the α subclass of the class Proteobacteria. The extent of nitrate removal efficiency was 99% at 200 mg/L NO3 and the nitrite content of the effluent was in the prescribed limit. The experiments showed the ability of Pseudomonas stutzeri to rapidly remove nitrate under anoxic conditions. The strain showed to be potentially good candidate for biodenitrification of high nitrate solutions. Key words: Pseudomonas stutzeri; Denitrification; Polymerase Chain Reaction, Isolation; Characterization INTRODUCTION Biological denitrification is a process carried to respire anaerobically using nitrogen oxides as out by numerous genera of bacteria. -
Influence of Denitrification in Aquatic Sediments on the Nitrogen Content of Natural Waters J
6 / c__ Influence of denitrification in aquatic sediments on the nitrogen content of natural waters J. F. van Kessel Influence of denitrification in aquatic sedimentso n the nitrogen content of naturalwater s Proefschrift ter verkrijging van degraa d van doctor in de landbouwwetenschappen, op gezagva n derecto r magnificus, dr. ir. J. P.H .va n derWant , hoogleraar in devirologie , in het openbaar te verdedigen opvrijda g 8oktobe r 1976 desnamiddag s te vier uur in de aula van de Landbouwhogeschool te Wageningen Centrefor Agriculture Publishingand Documentation Wageningen —1976 Abstract Kessel, J. F. van (1976) Influence of denitrification in aquatic sediments on the nitrogen content of natural waters. Agric. Res. Rep. (Versl. landbouwk. Onderz.) 858. Pudoc, Wageningen. ISBN 90 220062 04 . (vi)+ 5 2 p.: 12figs ; 14 tables;Eng .an d Dutch summaries. Forms part of a doctoral thesis, Wageningen ((vii) + 104 p., 43 figs, 28 tables). Other parts are published in Water Research,bu t are summarized in the Agric.Res .Rep . A study was made of microbiological processes, particularly denitrification, leading to the elimi nation of nitrogen from natural waters. As denitrification is an anaerobic process and natural waters mostly contain dissolved oxygen, this process was suggested to proceed in the anaerobic sediment at the bottom of natural waters. Two widely differing types of aquatic sediments were tested in the laboratory for effects of temperature, oxygen and nitrate in the overlying water, and thickness of the sediment layer on the rate of denitrification. During disappearance of nitrate from the overlying water, by far most of thenitrat e was converted to molecular nitrogen by denitrification and only a small part of the nitrate was utilized for cell synthesis (immobilization).