Journal articles on the topic 'Organics matter'
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1
Amon, Rainer M. W. "Ocean dissolved organics matter." Nature Geoscience 9, no. 12 (November 14, 2016): 864–65. http://dx.doi.org/10.1038/ngeo2841.
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Roelofs, G. J. "A GCM study of organic matter in marine aerosol and its potential contribution to cloud drop activation." Atmospheric Chemistry and Physics Discussions 7, no. 2 (April 27, 2007): 5675–700. http://dx.doi.org/10.5194/acpd-7-5675-2007.
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Abstract. With the global aerosol-climate model ECHAM5-HAM we investigate the potential influence of organic aerosol originating from the ocean on aerosol mass and chemical composition and the droplet concentration and size of marine clouds. We present sensitivity simulations in which the uptake of organic matter in the marine aerosol is prescribed for each aerosol mode with varying organic mass and mixing state, and with a geographical distribution and seasonality similar to the oceanic emission of dimethyl sulfide. Measurements of aerosol mass and chemical composition serve to evaluate the representativity of the model initializations. Good agreement with the measurements is obtained when organic matter is added to the Aitken, accumulation and coarse modes simultaneously. Representing marine organics in the model leads to higher cloud drop number concentrations, smaller cloud drop effective radii, and a better agreement with remote sensing measurements. The mixing state of the organics and the other aerosol matter, i.e., internal or external depending on the formation process of aerosol organics, is an important factor for this. We estimate that globally about 75 Tg C yr−1 of organic matter from marine origin enters the aerosol phase. An approximate 35% of this occurs through formation of secondary organic aerosol and 65% through emission of primary particles.
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Roelofs, G. J. "A GCM study of organic matter in marine aerosol and its potential contribution to cloud drop activation." Atmospheric Chemistry and Physics 8, no. 3 (February 13, 2008): 709–19. http://dx.doi.org/10.5194/acp-8-709-2008.
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Abstract. With the global aerosol-climate model ECHAM5-HAM we investigate the potential influence of organic aerosol originating from the ocean on aerosol mass and chemical composition and the droplet concentration and size of marine clouds. We present sensitivity simulations in which the uptake of organic matter in the marine aerosol is prescribed for each aerosol mode with varying organic mass and mixing state, and with a geographical distribution and seasonality similar to the oceanic emission of dimethyl sulfide. Measurements of aerosol mass, aerosol chemical composition and cloud drop effective radius are used to assess the representativity of the model initializations. Good agreement with the measurements is obtained when organic matter is added to the Aitken, accumulation and coarse modes simultaneously. Representing marine organics in the model leads to higher cloud drop number concentrations and thus smaller cloud drop effective radii, and this improves the agreement with measurements. The mixing state of the organics and the other aerosol matter, i.e. internal or external depending on the formation process of aerosol organics, is an important factor for this. We estimate that globally about 75 Tg C yr−1 of organic matter from marine origin enters the aerosol phase, with comparable contributions from primary emissions and secondary organic aerosol formation.
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Zhang, Feng, Shuai Li, Chang Qing Liu, Xing Sheng Kang, and Yan Li. "The Component and Characteristic Analysis of Organic Matters in Inflow Water of one Wastewater Treatment Plant in Qingdao." Advanced Materials Research 518-523 (May 2012): 2886–90. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.2886.
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The concentration of soluble inert organics and the mass distribution of organic matter in inflow wastewater of one wastewater treatment plant (WWTP) in Qingdao city in China were studied in this paper. The results showed that the concentration of soluble inert organics in the influent which cannot be degraded by microbe was about 20 mg/L, accounts for 2%～5% of all dissolved organic matter. The small organic molecules (<1 ku) took up the largest proportion of all organics in influent, which was about 40% of dissolved organic carbon (DOC). Moreover, the residual organic molecules after biological treatment process and coagulation sedimentation process might be transformed into disinfection by-products (DBPs) by chlorination in advanced treatment process, so the combined process of ozone and activated carbon was suggested to be used to remove the small organic molecules in inflow water in this WWTP.
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Alderson, Danielle M., Martin G. Evans, James J. Rothwell, and Stephen Boult. "Classifying sedimentary organics:." Progress in Physical Geography: Earth and Environment 40, no. 3 (January 27, 2016): 450–79. http://dx.doi.org/10.1177/0309133315625864.
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Sediments are crucial to the understanding of environmental processes and conditions in a variety of systems. The study of sediments often focuses on quantity, but should involve more emphasis on the quality of the organic component, by utilising commonplace techniques employed by other disciplines. We provide a classification scheme that will allow those interested in organic matter quality to decide on appropriate techniques to apply, and discuss a variety of applications of the investigation of organic matter quality in diverse areas of Physical Geography. Firstly, this paper conceptualises organic matter quality by examining how different groups identify with this term, providing a classification scheme that may assist individuals in their exploration of organic matter character. Secondly, it identifies key areas of investigation linked to Physical Geography where research into organic matter quality may provide a necessary or useful component. Finally, it explains and evaluates crucial techniques for characterising organic matter quality.
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Sun, Xiao Ming, Jing Yang Liu, Qi Qiao, Yue Zhang, Na Zhang, and Li Hong Meng. "Application of Reverse Osmosis Membrane in Wastewater Treatmente." Applied Mechanics and Materials 737 (March 2015): 661–63. http://dx.doi.org/10.4028/www.scientific.net/amm.737.661.
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Reverse osmosis membrane is usually used to desalination. With the development of membrane materials and technology, the performance of reverse osmosis membrane is improved continuously, and the interception rate of organic matter is higher, the separation rate of the organic matter is obviously improved. The research progress and application status of separating organics in aqueous solution by reverse osmosis membrane is presented in this paper. The future research direction and application of reverse osmosis membrane for separating organics from aqueous solution were also analyzed and prospected.
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Keen, Olya S. "Characterisation of ultraviolet-absorbing recalcitrant organics in landfill leachate for treatment process optimisation." Waste Management & Research: The Journal for a Sustainable Circular Economy 35, no. 3 (November 24, 2016): 325–28. http://dx.doi.org/10.1177/0734242x16678065.
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Organics in leachate from municipal solid waste landfills are notoriously difficult to treat by biological processes. These organics have high ultraviolet absorbance and can interfere with the ultraviolet disinfection process at the wastewater treatment plant that receives leachate if the leachate flow contribution is large enough. With more wastewater treatment plants switching to ultraviolet disinfection, landfills face increased pressure to treat leachate further. This study used size exclusion chromatography, fluorescence spectroscopy and ultraviolet/Vis spectrophotometry to characterise the bulk organic matter in raw landfill leachate and the biorecalcitrant organic matter in biologically treated leachate from the same site. The results indicate that biorecalcitrant organics have the polyphenolic absorbance peak at 280 nm, fluorescence peak at 280 nm excitation and 315 nm emission, and molecular size range of 1000–7000 Da, all of which are consistent with lignin. The lignin-like nature of biorecalcitrant leachate organics is supported by the fact that 30%–50% of municipal solid waste consists of plant debris and paper products. These findings shed light on the nature of biorecalcitrant organics in leachate and will be useful for the design of leachate treatment processes and further research on leachate treatment methods.
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Hu, J. Y., and J. H. Shan. "Control of RO/NF organic fouling by monitoring and modification of organic polarity of feed water." Water Supply 8, no. 4 (October 1, 2008): 467–72. http://dx.doi.org/10.2166/ws.2008.092.
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The organics in surface water and treated wastewater were analyzed for their polarity by a modified natural organic matter polarity rapid assessment method (NOM-PRAM). Selected water samples were then introduced to reverse osmosis (RO) and nanofiltration (NF) membrane system to study the relationship between organics polarity and membrane fouling. Results showed that the more organic fractions with non-polar property, the more serious fouling found for both RO and NF. Pre-treatment with KMnO4 was then conducted to modify the organics polarity in feed water. Under the optimum dosage, where more non-polar organics were converted to polar or negatively charged fractions, the subsequent membrane fouling was found to be reduced.
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Kuga, Maïa, Bernard Marty, Yves Marrocchi, and Laurent Tissandier. "Synthesis of refractory organic matter in the ionized gas phase of the solar nebula." Proceedings of the National Academy of Sciences 112, no. 23 (May 26, 2015): 7129–34. http://dx.doi.org/10.1073/pnas.1502796112.
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In the nascent solar system, primitive organic matter was a major contributor of volatile elements to planetary bodies, and could have played a key role in the development of the biosphere. However, the origin of primitive organics is poorly understood. Most scenarios advocate cold synthesis in the interstellar medium or in the outer solar system. Here, we report the synthesis of solid organics under ionizing conditions in a plasma setup from gas mixtures (H2(O)−CO−N2−noble gases) reminiscent of the protosolar nebula composition. Ionization of the gas phase was achieved at temperatures up to 1,000 K. Synthesized solid compounds share chemical and structural features with chondritic organics, and noble gases trapped during the experiments reproduce the elemental and isotopic fractionations observed in primitive organics. These results strongly suggest that both the formation of chondritic refractory organics and the trapping of noble gases took place simultaneously in the ionized areas of the protoplanetary disk, via photon- and/or electron-driven reactions and processing. Thus, synthesis of primitive organics might not have required a cold environment and could have occurred anywhere the disk is ionized, including in its warm regions. This scenario also supports N2 photodissociation as the cause of the large nitrogen isotopic range in the solar system.
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Kaplan, H. H., A. A. Simon, V. E. Hamilton, M. S. Thompson, S. A. Sandford, M. A. Barucci, E. A. Cloutis, et al. "Composition of organics on asteroid (101955) Bennu." Astronomy & Astrophysics 653 (September 2021): L1. http://dx.doi.org/10.1051/0004-6361/202141167.
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Context. The Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) mission detected an infrared absorption at 3.4 μm on near-Earth asteroid (101955) Bennu. This absorption is indicative of carbon species, including organics, on the surface. Aims. We aim to describe the composition of the organic matter on Bennu by investigating the spectral features in detail. Methods. We use a curated set of spectra acquired by the OSIRIS-REx Visible and InfraRed Spectrometer that have features near 3.4 μm (3.2 to 3.6 μm) attributed to organics. We assess the shapes and strengths of these absorptions in the context of laboratory spectra of extraterrestrial organics and analogs. Results. We find spectral evidence of aromatic and aliphatic CH bonds. The absorptions are broadly consistent in shape and depth with those associated with insoluble organic matter in meteorites. Given the thermal and space weathering environments on Bennu, it is likely that the organics have not been exposed for long enough to substantially decrease the H/C and destroy all aliphatic molecules.
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Perron, N., J. Sandradewi, M. R. Alfarra, P. Lienemann, R. Gehrig, A. Kasper-Giebl, V. A. Lanz, et al. "Composition and sources of particulate matter in an industrialised Alpine valley." Atmospheric Chemistry and Physics Discussions 10, no. 4 (April 14, 2010): 9391–430. http://dx.doi.org/10.5194/acpd-10-9391-2010.
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Abstract. A three-week long field campaign was carried out under autumnal meteorological conditions at four valley floor sites in the industrialised Swiss Rhone Valley. For one week of stable meteorological conditions, particulate matter with an aerodynamic diameter below 10 μm (PM10) was analysed from daily filters using ion chromatography, X-ray fluorescence, anhydrosugars and radiocarbon analysis of the organic and elemental matter (OM and EM, respectively). Furthermore, PM1 composition along the whole campaign was monitored in Massongex (a site near industries) by a seven-wavelength aethalometer and a quadrupole aerosol mass spectrometer (Q-AMS). At all sites, PM10 secondary inorganics and non-fossil EM and OM exhibited relatively stable concentrations over the selected days. On the contrary, PM10 fossil carbonaceous fractions, mineral dust components and several trace elements showed a significant decrease on Sunday, compared to the analysed working days. Their concentrations were also highly correlated. This evidenced the role of exhaust and resuspension emissions by heavy-duty vehicle traffic to the PM10 concentrations along the valley. In Massongex, organic matter and black carbon (BC) were the main contributors to PM1 over the campaign (accounting for 45% and 18% of PM1, respectively). An optical discrimination of BC highlighted the prevalence of fossil over wood-burning sources. Three types of PM1 organics could be identified by factor analysis: primary wood-burning organic aerosol (P-WBOA) dominated the PM1 carbonaceous fraction, followed by oxygenated organics (OOA) mostly representing secondary organics, and by traffic or possibly industry-related hydrocarbon-like organics (HOA) as the smallest carbonaceous contribution. Furthermore, unusually high contributions of fine chloride were detected at all sites. They were attributed to ammonium chloride (NH4Cl) in Massongex and represented the only significant component exclusively attributable to industrial emissions.
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Kim, Moonil, Dukkyu Han, Fenghao Cui, and Wookeun Bae. "Recalcitrant organic matter removal from textile wastewater by an aerobic cell-immobilized pellet column." Water Science and Technology 67, no. 9 (May 1, 2013): 2124–31. http://dx.doi.org/10.2166/wst.2013.104.
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The treatment of textile wastewater is difficult because of its recalcitrant organic content. The biological removal of recalcitrant organics requires a long retention time for microbial growth. Activated sludge was immobilized in a polyethylene glycol pellet to allow for sufficient sludge retention time. The pellets were filled in an aerobic cell-immobilized pellet column (CIPC) reactor in order to investigate the removal of recalcitrant organics from textile wastewater. A textile wastewater effluent treated by a conventional activated sludge reactor was used as a target wastewater. The chemical oxygen demand (COD) removal efficiency of the aerobic CIPC reactor at various empty bed contact times was in the range of 42.2–60.5%. Half of the input COD was removed in the lower part (bottom 25% of the reactor volume) of the reactor when the organic loading rate was less than 1.5 kg COD/(m3•d). About 15–30% of the input COD was removed in the remaining part of the column reactor. The COD removed in this region was limitedly biodegradable. The biodegradation of recalcitrant organics could be carried out by the interactional functions of the various bacteria consortia by using a cell-immobilization process. The CIPC process could effectively treat textile wastewater using a short retention time because the microorganisms that degrade limitedly biodegradable organics were dominant in the reactor.
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Hejzlar, J., P. Dolejš, J. Komárková, J. Sed′a, K. Šimek, and V. Vyhnálek. "Effect of biomanipulation on the structuring of the planktonic food web and water treatability by coagulation." Water Science and Technology 37, no. 2 (January 1, 1998): 105–12. http://dx.doi.org/10.2166/wst.1998.0116.
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The impact of planktivorous fish on the plankton community structure and character of aquatic organic matter was studied by a meso-scale enclosure experiment in a stratified reservoir. Aims of the study were (i) to examine the response of the communities with and without herbivorous zooplankton to an increased input of phosphorus and (ii) to determine the composition and coagulation properties of the organic matter produced by these communities. The concentration and composition of organic matter were affected both in the enclosure with planktivorous fish (F), where high algal biomass developed, and in the enclosure without fish (Z), where algae were maintained at a low concentration by zooplankton grazing. Although differences between the enclosures in concentrations of total dissolved organic matter and its hydrophobic, hydrophilic and neutral/basic fractions were relatively small, coagulation properties of the organics differed substantially. Particulate and dissolved organic matter produced in enclosure F had a positive effect on the efficiency of alum coagulation in contrast to the less readily separable organics produced in enclosure Z. The results indicate that pelagic food web manipulations to maintainin low phytoplankton biomass by zooplankton grazing may not always have positive effects on the treatability of water by coagulation.
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Fuentes, E., H. Coe, D. Green, and G. McFiggans. "On the impacts of phytoplankton-derived organic matter on the properties of the primary marine aerosol – Part 2: Composition, hygroscopicity and cloud condensation activity." Atmospheric Chemistry and Physics 11, no. 6 (March 18, 2011): 2585–602. http://dx.doi.org/10.5194/acp-11-2585-2011.
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Abstract. The effect of nanogel colloidal and dissolved organic matter <0.2 μm, secreted by marine biota, on the hygroscopic growth and droplet activation behaviour of the primary marine aerosol was studied. Seawater proxies were prepared by the combination of artificial seawater devoid of marine organics and natural seawater enriched in organic exudate released by laboratory-grown phytoplankton cultures, as described in a companion paper. The primary aerosol was produced by bubble bursting, using a plunging multijet system as an aerosol generator. The aerosol generated from seawater proxies enriched with marine exudate presented organic volume fractions on the order of 8–37%, as derived by applying a simple mixing rule. The hygroscopic growth and cloud condensation nuclei (CCN) activity of the marine organics-enriched particles where 9–17% and 5–24% lower, respectively, than those of the aerosol produced from artificial seawater devoid of exudate. Experiments in a companion paper indicated that the cloud nuclei formation could be enhanced in diatom bloom areas because of the increase in the primary particle production induced by marine organics. The experiments in the present study, however, indicate that the impacts of such an enhancement would be counteracted by the reduction in the CCN activity of the primary particles enriched in marine organics. The extent of the effect of the biogenic matter on the particle behaviour was dependent on the seawater organic concentration and type of algal exudate. Aerosol produced from seawater proxies containing diatomaceous exudate presented higher hydrophobicity and lower CCN activity than those enriched with nanoplankton exudate. The organic fraction of the particles was found to correlate with the seawater organic concentration, without observing saturation of the particle organic mass fraction even for unrealistically high organic matter concentration in seawater. These findings are indicative that discrepancies on the composition of the primary aerosol between different studies could partly be explained by the difference in the nature and concentration of the organic matter in the source seawater employed. Consistently across the experiments, theoretical analysis based on the Köhler model predicted a reduction in the primary marine aerosol CCN activity upon the incorporation of marine organics into the particle composition. This effect is consequence of the replacement of small inorganic sea salt molecules by large molar mass organic molecules, together with a moderate suppression of the surface tension at the point of activation of 5–0.5%, which leads to a dominance of the reduction in the dissolved solute in the Raoult term.
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De Sanctis, Maria Cristina, and Eleonora Ammannito. "Organic Matter and Associated Minerals on the Dwarf Planet Ceres." Minerals 11, no. 8 (July 22, 2021): 799. http://dx.doi.org/10.3390/min11080799.
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Ceres is the largest object in the main belt and it is also the most water-rich body in the inner solar system besides the Earth. The discoveries made by the Dawn Mission revealed that the composition of Ceres includes organic material, with a component of carbon globally present and also a high quantity of localized aliphatic organics in specific areas. The inferred mineralogy of Ceres indicates the long-term activity of a large body of liquid water that produced the alteration minerals discovered on its surface, including ammonia-bearing minerals. To explain the presence of ammonium in the phyllosilicates, Ceres must have accreted organic matter, ammonia, water and carbon present in the protoplanetary formation region. It is conceivable that Ceres may have also processed and transformed its own original organic matter that could have been modified by the pervasive hydrothermal alteration. The coexistence of phyllosilicates, magnetite, carbonates, salts, organics and a high carbon content point to rock–water alteration playing an important role in promoting widespread carbon occurrence.
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Venegas, Gabriel R., Madeline R. Frey, Kevin M. Lee, Megan S. Ballard, W. Cyrus Clemo, and Kelly M. Dorgan. "Biogeoacoustic sediment properties along a horizontal sand-mud gradient." Journal of the Acoustical Society of America 150, no. 4 (October 2021): A350. http://dx.doi.org/10.1121/10.0008551.
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Whether deposited from the water column or generated by benthic infauna, interstitial organic matter is a ubiquitous constituent of marine sediment and is particularly prevalent in sediments with significant silt/clay fractions. Interstitial organic matter suspends silt and clay particles in the sediment matrix, adsorbs onto mineral surfaces, and resides between mineral contacts, all of which are hypothesized to alter geoacoustic properties. However, the extent to which interstitial organics alter geoacoustic properties is understudied and warrants further investigation. To address this, diver cores were collected along a horizontal sand-mud gradient in Mobile Bay, Alabama. The sediment was subsequently processed in the laboratory, where compressional wave speed (10 kHz to 1 MHz), compressional wave attenuation (100 kHz to 1 MHz), density, porosity, grain-size distribution, and organic carbon and nitrogen content were measured. In addition, physics-based geoacoustic models, such as VGS(λ) and mCREB, were fit to the wide range of sediment types. Measured geoacoustic properties and fit parameters inherent to each sediment acoustics model are compared with organic sediment properties. The extent to which organics control sediment geoacoustic properties and considerations to include organics in future modeling efforts will be discussed. [Work sponsored by ONR.]
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Fuentes, E., H. Coe, D. Green, and G. McFiggans. "On the impacts of phytoplankton-derived organic matter on the properties of the primary marine aerosol – Part 2: Composition, hygroscopicity and cloud condensation activity." Atmospheric Chemistry and Physics Discussions 10, no. 11 (November 4, 2010): 26157–205. http://dx.doi.org/10.5194/acpd-10-26157-2010.
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Abstract. The effect of colloidal and dissolved organic matter <0.2 μm, secreted by marine biota, on the hygroscopic growth and droplet activation behaviour of the primary marine aerosol was studied. Seawater proxies were prepared by the combination of artificial seawater devoid of marine organics and natural seawater enriched in organic exudate released by laboratory-grown phytoplankton cultures, as described in a companion paper. The primary aerosol was produced by bubble bursting, using a plunging multijet system as an aerosol generator. The aerosol generated from seawater proxies enriched with marine exudate presented organic volume fractions on the order of 5–37%, as derived by applying a simple mixing rule. The hygroscopic growth and cloud condensation nuclei (CCN) activity of the marine organics-enriched particles where 9–17% and 5–24% lower, respectively, than those of the aerosol produced from artificial seawater devoid of exudate. Experiments in a companion paper indicated that the cloud nuclei formation could be enhanced in diatom bloom areas because of the increase in the primary particle production induced by marine organics. The experiments in the present study, however, indicate that the impacts of such an enhancement would be counteracted by the reduction in the CCN activity of the primary particles enriched in marine organics. The extent of the effect of the biogenic matter on the particle behaviour was dependent on the seawater organic concentration and type of algal exudate. Aerosol produced from seawater proxies containing diatomaceous exudate presented higher hydrophobicity and lower CCN activity than those enriched with nanoplankton exudate. The organic fraction of the particles increased with increasing seawater organic concentration, with the highest organic enrichment found for the diatomaceous exudate. These findings are indicative that, besides the differences induced by the aerosol generator employed, discrepancies between different studies in the behaviour of the organics-enriched primary seaspray could partly be explained by the difference in the nature and concentration of the organic material in the source seawater employed. Consistently across the experiments, theoretical analysis based on the Köhler model predicted a reduction in the primary seaspray CCN activity upon the incorporation of marine organics into the particle composition. This effect is consequence of the replacement of small inorganic sea salt molecules by large molar mass organic molecules, together with a moderate suppression of the surface tension at the point of activation of 5–0.5%, which leads to a dominance of the reduction in the dissolved solute in the Raoult term.
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Tartèse, Romain, Marc Chaussidon, Andrey Gurenko, Frédéric Delarue, and François Robert. "Insights into the origin of carbonaceous chondrite organics from their triple oxygen isotope composition." Proceedings of the National Academy of Sciences 115, no. 34 (August 6, 2018): 8535–40. http://dx.doi.org/10.1073/pnas.1808101115.
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Dust grains of organic matter were the main reservoir of C and N in the forming Solar System and are thus considered to be an essential ingredient for the emergence of life. However, the physical environment and the chemical mechanisms at the origin of these organic grains are still highly debated. In this study, we report high-precision triple oxygen isotope composition for insoluble organic matter isolated from three emblematic carbonaceous chondrites, Orgueil, Murchison, and Cold Bokkeveld. These results suggest that the O isotope composition of carbonaceous chondrite insoluble organic matter falls on a slope 1 correlation line in the triple oxygen isotope diagram. The lack of detectable mass-dependent O isotopic fractionation, indicated by the slope 1 line, suggests that the bulk of carbonaceous chondrite organics did not form on asteroidal parent bodies during low-temperature hydrothermal events. On the other hand, these O isotope data, together with the H and N isotope characteristics of insoluble organic matter, may indicate that parent bodies of different carbonaceous chondrite types largely accreted organics formed locally in the protosolar nebula, possibly by photochemical dissociation of C-rich precursors.
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Wan Abdul Razak, Wan Razarinah, Noor Zalina Mahmood, and Noorlidah Abdullah. "Effect of Culture Technique of Ganoderma Australe Mycelia on Percentage Removal of Leachate Organics." Scientific Research Journal 13, no. 1 (June 30, 2016): 131. http://dx.doi.org/10.24191/srj.v13i1.5447.
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Leachate (liquid pollutant), which is highly contaminated with organic matter and toxic substances is a major problem that arised from landfill. Biological methods have proven to be effective to remove organic matters that are abundant in leachate. This study is intended to compare the used of free mycelia and immobilized mycelia of the white-rot fungi, Ganoderma australe for the removal of landfill leachate organics. The organics fraction of landfill leachate was measured by biological oxygen demand (BOD5), and chemical oxygen demand (COD). The experiment revealed that free mycelia of G. australe showed capability in removing leachate BOD5 but not COD. However, the use of immobilized G. australe displayed the best result in the removal of BOD5 and COD leachate after 4 weeks of treatment in flasks with 93.09% and 17.84% percentage removal of BOD5 and COD, respectively. Therefore, G. australe can be considered potentially useful in the treatment of landfill leachate as they can help in removing BOD and COD due to their biodegradative abilities.
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Wan Abdul Razak, Wan Razarinah, Noor Zalina Mahmood, and Noorlidah Abdullah. "Effect of Culture Technique of Ganoderma Australe Mycelia on Percentage Removal of Leachate Organics." Scientific Research Journal 13, no. 1 (June 1, 2016): 131. http://dx.doi.org/10.24191/srj.v13i1.9387.
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Leachate (liquid pollutant), which is highly contaminated with organic matter and toxic substances is a major problem that arised from landfill. Biological methods have proven to be effective to remove organic matters that are abundant in leachate. This study is intended to compare the used of free mycelia and immobilized mycelia of the white-rot fungi, Ganoderma australe for the removal of landfill leachate organics. The organics fraction of landfill leachate was measured by biological oxygen demand (BOD5), and chemical oxygen demand (COD). The experiment revealed that free mycelia of G. australe showed capability in removing leachate BOD5 but not COD. However, the use of immobilized G. australe displayed the best result in the removal of BOD5 and COD leachate after 4 weeks of treatment in flasks with 93.09% and 17.84% percentage removal of BOD5 and COD, respectively. Therefore, G. australe can be considered potentially useful in the treatment of landfill leachate as they can help in removing BOD and COD due to their biodegradative abilities.
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Boller, M. "Removal of Organic Matter by Physico-Chemical Mechanisms in Wastewater Treatment Plants." Water Science and Technology 27, no. 11 (June 1, 1993): 167–83. http://dx.doi.org/10.2166/wst.1993.0275.
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Solids separation, adsorption onto participates and volatilization are the main physico-chemical mechanisms responsible for the removal of organic matter in wastewater treatment plants. In addition, solids separation as well as adsorption performance may be enhanced by chemical flocculation/precipitation with hydrolyzing metal salts. With the help of particle size distributions and other characteristics of the particulates at different treatment stages, more insight can be gained into the interactions between paniculate properties and solids separation performance. Significant removal of trace organics is achieved by adsorption onto paniculate surfaces and stripping in aeration tanks. Examples illustrate the adsorption of the relatively large quantities of substances contained in detergents and reveal the effect on water and sludge quality. Octanol/water partition coefficients of trace organics may be used together with oxygen transfer characteristics to determine the potential of volatilization into the air. The effect of flocculants on paniculate and dissolved organics removal in wastewater treatment is illustrated when Fe-salts are dosed to raw sewage, to the biological stage or to tertiary filters.
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Tozzi, Gian Paolo, and Ludmilla Kolokolova. "Solid organics in cometary comae." Proceedings of the International Astronomical Union 4, S251 (February 2008): 313–14. http://dx.doi.org/10.1017/s1743921308021807.
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AbstractIt is known since long ago that in comets a large quantity of organic matter exists in form of grains or is embedded in silicate grains. This was detected in situ by cometary space missions as well as inferred as a distributed source of some molecules observed in comets. Since organic matter is rather volatile, finding slow sublimating grains in comets can be good evidence of organics as a constituent of such grains. Here we describe a method to detect sublimating grains in comets. It consists of specific observations, specific data analysis, and some light-scattering modeling. We detect sublimating grains by measuring the quantity of grains as a function of the nucleocentric distance. Once detected, it is possible to get their photometric characteristics and compare them with the results of light-scattering modeling. The method has been applied to several comets. Sublimating grains were reliably identified for two of them.
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Zhang, Aiping, Zhepei Gu, Weiming Chen, and Qibin Li. "Degradation of leachate from a semi-anaerobic aged refuse biofilter by the ZVI/H2O2 process coupled with microwave irradiation: optimization, organics transformation, and reaction mechanisms." Environmental Science: Water Research & Technology 4, no. 10 (2018): 1695–709. http://dx.doi.org/10.1039/c8ew00469b.
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The semi-aerobic aged refuse biofilter (SAARB) is highly efficient in removing organic matter and ammonia nitrogen, but the effluent of the SAARB (SAARB leachate) contains high concentrations of recalcitrant organics.
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Seo, G. T., T. S. Lee, B. H. Moon, K. S. Choi, and H. D. Lee. "Membrane separation activated sludge for residual organic removal in oil wastewater." Water Science and Technology 36, no. 12 (December 1, 1997): 275–82. http://dx.doi.org/10.2166/wst.1997.0457.
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A hybrid membrane separation activated sludge process was investigated for treatment of residual organic matter in oily wastewater from an automobile engine manufacturing plant. A bench scale experiment was conducted to identify the biodegradability of the residual organic matter in activated sludge reactors at various HRT (equal to SRT), such as 5, 10, 20, 30 days. Removal efficiency of higher than 90% was obtained in terms of SCOD at more than 10 day HRT showing the possibility of biological treatment. Ultrafiltration test was also carried out for the residual organics using cross-flow membrane filtration system at transmembrane pressure (TMP) of 2.0 kg/cm2. The membrane used for this experiment was polysulfone hollow fiber membrane with 30,000 molecular weight cut off. The rejection rate was around 10% in terms of TCOD. This low rejection rate explains that the residual organics in the oil wastewater are soluble and their MWCO size distribution might be less than 30,000. However the combined membrane activated sludge process could maintain significantly high removal efficiency more than 95% for the residual organics in the oily wastewater. The enhancement in organic removal was estimated to be contributed to the increased biomass in the system resulting in the reduction of the organic loading.
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Karlsson, Ingemar, and Gunnar Smith. "Pre-Precipitation Facilitates Nitrogen Removal without Tank Expansion." Water Science and Technology 22, no. 7-8 (July 1, 1990): 85–92. http://dx.doi.org/10.2166/wst.1990.0233.
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Chemically coagulated sewage water gives an effluent low in both suspended matter and organics. To use chemical precipitation as the first step in waste water treatment improves nitrification in the following biological stage. The precipitated sludge contains 75% of the organic matter in the sewage and can by hydrolysis be converted to readily degradable organic matter, which presents a valuable carbon source for the denitrification process. This paper will review experiences from full-scale applications as well as pilot-plant and laboratory studies.
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Karlsson, Ingemar, and Gunnar Smith. "Pre-Precipitation Facilitates Nitrogen Removal without Tank Expansion." Water Science and Technology 23, no. 4-6 (February 1, 1991): 811–17. http://dx.doi.org/10.2166/wst.1991.0532.
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Chemically coagulated sewage water gives an effluent low in both suspended matter and organics. To use chemical precipitation as the first step in waste water treatment improves nitrification in the following biological stage. The precipitated sludge contains 75% of the organic matter in the sewage and can by hydrolysis be converted to readily degradable organic matter, which presents a valuable carbon source for the denitrification process. This paper will review experiences from full scale applications as well as pilot plant- and laboratory studies.
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D. ANDREWS, JOHN, ERNEST G. ALEXANDER, and PETER W. HART. "Reconciling material balances with laboratory test results: The case of the inorganic-to-organic ratio in black liquor." TAPPI Journal 14, no. 9 (October 1, 2015): 593–97. http://dx.doi.org/10.32964/tj14.9.593.
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When evaluating the composition of black liquor using material balance techniques that estimate the organics from the wood and the inorganics from the cooking liquor, the solids content of the black liquor is determined to be roughly 1/3 inorganic matter and 2/3 organic matter. When actual laboratory testing using simplified ashing methodologies are performed, the results typically suggest that black liquor solids contain roughly 43%-49% organics and 51%-57% inorganics. We determined that the applied hydroxide and sulfide mineralize carbon and oxygen from the organic portion of the black liquor and convert it to carbonate and sulfate during the cooking and ashing process, thus increasing the apparent inorganic content of the black liquor. This becomes problematic when attempting to estimate total black liquor production using the organics removed during cooking and the inorganic content using results from the ashed black liquor sample. We used Microsoft Excel material balances to develop a conversion factor to correct the laboratory test results. Multiplying the percent ash in the laboratory test by 0.65 to 0.70 provided a more realistic estimate of the initial inorganics to be used along with organics removed in the digester to estimate black liquor production. This conversion factor was determined to be independent of pulp yield and white liquor charge in the digester. The initial white liquor composition, as reported by the ABC test, does have a slight effect on this value.
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Dziubek, Andrzej M., and Apolinary L. Kowal. "Modelling of the Coagulation–Adsorption Process in Treatment Systems." Water Science and Technology 17, no. 6-7 (June 1, 1985): 1113–20. http://dx.doi.org/10.2166/wst.1985.0206.
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Removal of organics in water or wastewater treatment systems is often described mathematically in the form of Langmuir and Freundlich adsorption isotherms. Using these equations, it is convenient to model, e.g., the removal of organic matter in the adsorption process on an activated carbon bed. In chemical treatment processes, organic substances are frequently removed from the water or wastewater under treatment via an adsorption on the precipitation products. In this paper presented is a generalized model of the equation of a multilayer adsorption isotherm, which describes TOC removal from a solution during chemical treatment in an alkaline medium. The model also includes the nonremovable concentration of organics.
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Verret, Marjolaine, Yifeng Wang, Jean Bjornson, and Denis Lacelle. "Hummocks in alpine tundra, northern British Columbia, Canada: distribution, morphology and organic carbon composition." Arctic Science 5, no. 3 (September 1, 2019): 127–47. http://dx.doi.org/10.1139/as-2018-0021.
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Hummocks develop by cryoturbation in fine-grained frost-susceptible soils and their stage of maturity may affect the translocation of organics in Cryosols. This study examines the distribution and morphology of hummocks in the Chuck Creek Trail Valley (northern British Columbia) and determines the quantity, distribution, and composition of organic matter in their soils. Hummocks occupy about 5%–20% of the valley and their morphology is largely affected by their silt content. Cryoturbated intrusions, radiocarbon dated to 2814 and 1648 cal year B.P., suggest that hummock development was initiated during the cooler late Holocene. Hummocks have an average soil organic carbon density of 16.3 kg m−2 in the uppermost 1 m, with 62% stored in the top 25 cm. Organics are mainly present as particulate organic matter in the O-horizon (25%–80%), characterized by degradable alkyl C and O/N-alkyl groups, but occur as mineral-associated organic matter (96%–98%) composed of recalcitrant aromatic and aliphatic C groups in the underlying B and C horizons. Minor differences in organic content and composition occur between hummock tops and troughs, and between hummocks showing different stages of maturity. In the absence of an observed frost table, contemporary hummock activity is attributed to seasonal freezing and thawing.
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Hu, M. A., J. R. Disnar, L. Barbanson, and I. Suarez-Ruiz. "Processus d'altération thermique, physico-chimique et biologique de constituants organiques et genèse d'une minéralisation sulfurée : le gîte Zn-Pb de La Florida (Cantabria, Espagne)." Canadian Journal of Earth Sciences 35, no. 8 (August 1, 1998): 936–50. http://dx.doi.org/10.1139/e98-041.
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The La Florida lead-zinc deposit (Cantabria, Spain), which is hosted by Urgonian carbonates, is located on the border of the Basco-cantabric Lower Cretaceous basin. The stratiform orebody, which is composed of sphalerite, galena, and barite in iron-dolostones, occurs in an envelope of dolostone. Organic matter studies have been carried out on samples from this deposit to understand its genesis and later evolution. The results of this work reveal the immatury of the autochthonous organic matter despite a slight paleothermal anomaly centred on the deposit. Various alteration processes have affected the hydrocarbons associated with autochthonous organic matter and (or) allochthonous bitumens, namely geochromatographic fractionation, water-washing, and biodegradation. Together with previous geological work, the results of this study are consistent with epigenetic and (or) diagenetic emplacement of the mineralization. The proposed genetic scheme involves hydrothermal fluids that would have acquired at least some of their characteristics during their upward migration through the Mesozoic cover. These solutions probably brought in the metals, the sulphates, and the organics all necessary for in situ hydrogen sulphide production and ore genesis. Sulphate reduction probably proceeded mostly at the expense of allochthonous organics by bacteria introduced by meteoric water infiltrations.
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Liu, Cheng, Wei Chen, and Nai Yuan Gao. "Removal of Organics from Huangpu River Water by Different Coagulants." Advanced Materials Research 113-116 (June 2010): 1128–31. http://dx.doi.org/10.4028/www.scientific.net/amr.113-116.1128.
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Jar-test experiments were performed to investigate the effectiveness of enhanced coagulation in organic removal from Huangpu river water. The results show that，For Huangpu river water, the suitable type of coagulant is ferrous chloride; the optimal pH for the removal of organics is 5.5, and the dose of FeCl3 is 30mg•L-1, at which the removal effect of the DOC ,UV254 are 42% ,56% and 60% respectively; As a matter of fact, ferric chloride and aluminum sulfate have similar removal effect to organics at ambient pH, while can gain higher efficiency at pH 5.5, (higher 12% DOC and 20% UV254), we can conclude that the main mechanism for coagulation to remove organics is the reactions between coagulants hydrolysis species and organics; Seen from the result of UV scan, the enhanced coagulation remove mainly the organics which can be adsorbed by the UV whose wavelength higher than 250 nm, which is mainly aromatic compounds and polynuclear aromatic hydrocarbons; Enhanced coagulation can reduce the chlorine demand of the raw water effectively, for it can remove the organics which can adsorbed by the UV at 272nm.
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Yu, Li E. "Impact of Molecular Mass of Natural Organic Matter on Biological Removal of Iron." Applied Mechanics and Materials 209-211 (October 2012): 1961–64. http://dx.doi.org/10.4028/www.scientific.net/amm.209-211.1961.
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Removal of iron in groundwater using biological filtration column are researched. Natural organics with different molecular mass can be removed using molecule filtration membrane. Test results showed that the molecular mass of organic influenced effluent quality. The greater is organic molecular mass, the lower the removal rate of iron, DOC and UV254. Removal rate of DOC and UV254 in groundwater with organic of molecular mass less than 1000 were 82.4% and 65.8%，respectively，but Removal rate of DOC and UV254 in groundwater with organic of molecular mass more than 30000 were 28.5% and 54.3% respectively.
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M. Farid, Ihab, Mohamed A. El-Ghozoli, Mohamed H. H. Abbas, Dalia S. El-Atrony, Hassan H. Abbas, Mohamed Elsadek, Hosam A. Saad, Nihal El Nahhas, and Ibrahim Mohamed. "Organic Materials and Their Chemically Extracted Humic and Fulvic Acids as Potential Soil Amendments for Faba Bean Cultivation in Soils with Varying CaCO3 Contents." Horticulturae 7, no. 8 (July 21, 2021): 205. http://dx.doi.org/10.3390/horticulturae7080205.
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Organic amendments are important sources of nutrients that release upon organic matter degradation, yet the stability of these organics in arid and semi-arid regions is relatively low. In contrast, humic substances (HS) are resistant to biodegradation and can keep nutrients in the soil available for the plant over a long time. Combinations between humic substances (HS) and mineral-N fertilizers are assumed to retain higher available nutrients in soils than those recorded for the sole application of either mineral or organic applications. We anticipate, however, that humic substances might not be as efficient as the organics from which they were extracted in increasing NP uptake by plants. To test these assumptions, faba bean was planted in a pot experiment under greenhouse conditions following a complete randomized design while considering three factors: two soils (calcareous and non-calcareous, Factor A), two organics (biogas and compost, Factor B) and combinations of the organics and their extracts (HA or FA) together with complementary doses of mineral-N ((NH4)2SO4) to attain a total rate of 50 kg N ha−1 (the recommended dose for faba bean plants) (Factor C). Results indicated that nitrogenase activity increased significantly due to the application of the used organics. In this respect, compost manure caused higher nitrogenase activity than biogas manure did. Humic substances raised NP-availability and the uptake by plants significantly; however, the values of increase were lower than those that occurred due to the compost or biogas manure. Moreover, the sole application of the used organics recorded the highest increases in plant biomass. Significant correlations were also detected between NP-availability, uptake and plant biomass. This means that HS could probably retain nutrients in available forms for long time periods, yet nutrients released continuously but slowly upon decomposition of organics seemed more important for plant nutrition.
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Wang, Yong, Jie Nian Jie, Zhi Yong Li, Li Guo Wang, Jiang Wu, Ye Tao, and Li Chun You. "Study on Mechanism of Removing the Organic Matter in Heavy Oil Sewage by the Electric Flocculation Method." Advanced Materials Research 535-537 (June 2012): 2201–8. http://dx.doi.org/10.4028/www.scientific.net/amr.535-537.2201.
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Oily sewage is one of the wastes produced in the oil industry production process and its quantity has been increasing year by year, which influences the environment and human health severely. Electric flocculation method is one of the wide application electrochemical treatment technologies for the oily wastewater treatment at home and abroad, which has higher efficiency than other technologies at the aspect of the organic pollutants degradation. A simulative experiment device dealing with heavy oil sewage by the electric flocculation method has been designed in this paper. The mechanism of the electric flocculation method in removing organic matter of the heavy oil sewage by analyzing the change of the composition and content of the organic matter in water samples before and after the process of the electric flocculation has been studied. Research results show: the carbon/tin dioxide electrode is better than the carbon/ ruthenium dioxide electrode in removing organic matter; most alkanes matters in the oily wastewater have been removed in the dispersing oil form by the electric flocculation; as the current density increases, the types and quantity of the response organic matter can be improved while types of the new synthetic organics increase. At the same time, this paper provides a theory support in specific optimization of the electricity flocculation flotation in oily wastewater treatment technology and process.
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van Leeuwen, J., C. Chow, R. Fabris, N. Withers, D. Page, and M. Drikas. "Application of a fractionation technique for better understanding of the removal of natural organic matter by alum coagulation." Water Supply 2, no. 5-6 (December 1, 2002): 427–33. http://dx.doi.org/10.2166/ws.2002.0200.
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To gain an improved understanding of the types of organic compounds that are recalcitrant to water treatment, natural organic matter (NOM) isolates from two drinking water sources (Mt. Zero and Moorabool reservoirs, Victoria, Australia) were separated into fractions of distinct chemical behaviour using resins. Four fractions were obtained from each water source and were organics absorbed to: (1) XAD-8 (very hydrophobic acids, VHA); (2) DAX-4 (slightly hydrophobic acids, SHA); (3) bound to an anion exchange resin (charged organics, CHAR); and (4) not absorbed or bound to resins (neutrals, NEUT). These fractions were then tested to determine the capacity of alum to remove them from water and to correlate this with the character of each isolate. The fractions were characterised by the application of high performance size exclusion chromatography (HPSEC), bacterial regrowth potential (BRP), trihalomethane formation potential (THMFP), pyrolysis gas-chromatography mass spectrometry (Py-GC-MS) and thermochemolysis. The highest removals of dissolved organic carbon (DOC) by alum treatment were in waters spiked with the CHAR fractions while the NEUT fractions were the most recalcitrant. The number average molecular weights (Mn) of DOC of the CHAR fractions before treatment were the highest, whilst those of the NEUT fractions were the lowest. After alum treatment, the Mn of the NEUT fractions were only slightly reduced. Results from Py-GC-MS and thermochemolysis indicate that the NEUT fractions had the highest relative proportion of saccharide derived organic material. Nonetheless, the BRP of waters spiked with the NEUT fractions differed markedly, indicating that organics recalcitrant to alum treatment can vary substantially in their chemical composition and capacity to support microbial growth.
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Wei, Qunshan, Rolando Fabris, Christopher W. K. Chow, Changzhou Yan, Dongsheng Wang, and Mary Drikas. "Characterization of dissolved organic matter from Australian and Chinese source waters by combined fractionation techniques." Water Science and Technology 64, no. 1 (July 1, 2011): 171–77. http://dx.doi.org/10.2166/wst.2011.432.
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The character of dissolved organic matter (DOM) in source waters from two countries (Australia and China) was investigated using an extended fractionation technique by combining resin adsorption, ultrafiltration and high performance size exclusion chromatography. There are distinctive chemical characteristics associated with DOM origins. Australian sourced DOM had higher hydrophobic acid (HoA) content and exhibited a more pronounced humic character, indicating a higher influence from allochthonous organics (decayed plant bodies from vegetated catchments). The higher content of hydrophobic base and neutral components found in Chinese DOM, may be attributed to the effects of increasing pollution caused by the rapid urbanization in China. The molecular weights (MWs) of aquatic HoA are predominantly in the moderate (e.g. 1–10 kDa) or small (e.g. <1 kDa) ranges. This suggests that aquatic HoA should not be assumed as high MW organics without experimental validation. It is also found that some of the low MW compounds in our samples were hydrophobic, which could explain the observation of low MW organic compounds being able to be removed by conventional treatment processes.
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Pu, Yunhui, Jialing Tang, Ting Zeng, Yisong Hu, Jixiang Yang, Xiaochang Wang, Jin Huang, and Abdelfatah Abomohra. "Pollutant Removal and Energy Recovery from Swine Wastewater Using Anaerobic Membrane Bioreactor: A Comparative Study with Up-Flow Anaerobic Sludge Blanket." Water 14, no. 15 (August 6, 2022): 2438. http://dx.doi.org/10.3390/w14152438.
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Due to its high content of organics and nutrients, swine wastewater has become one of the main environment pollution sources. Exploring high-efficient technologies for swine wastewater treatment is urgent and becoming a hot topic in the recent years. The present study introduces anaerobic membrane bioreactor (AnMBR) for efficient treatment of swine wastewater, compared with up-flow anaerobic sludge blanket (UASB) as a traditional system. Pollutant removal performance, methanogenic properties, and microbial community structures were investigated in both reactors. Results showed that by intercepting particulate organics, AnMBR achieved stable and much higher chemical oxygen demand (COD) removal rate (approximately 90%) than UASB (around 60%). Due to higher methanogenic activity of anaerobic sludge, methane yield of AnMBR (0.23 L/g-COD) was higher than that of UASB. Microbial community structure analysis showed enrichment of functional bacteria that can remove refractory organic matter in the AnMBR, which promoted the organics conversion processes. In addition, obvious accumulation of acetotrophic and hydrotrophic methanogens in AnMBR system was recorded, which could broaden the organic matter degradation pathways and the methanogenesis processes, ensuring a higher methane yield. Through energy balance analysis, results concluded that the net energy recovery efficiency of AnMBR was higher than that of UASB system, indicating that applying AnMBR for livestock wastewater treatment could not only efficiently remove pollutants, but also significantly enhance the energy recovery.
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Strmečki, Slađana, Jelena Dautović, and Marta Plavšić. "Constant current chronopotentiometric stripping characterisation of organic matter in seawater from the northern Adriatic, Croatia." Environmental Chemistry 11, no. 2 (2014): 158. http://dx.doi.org/10.1071/en13122.
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Environmental context We determined seasonal changes in the organic matter content of the northern Adriatic with newly applied electrochemical techniques able to measure catalytically active organics. The inflow of the Po River and its nutrient load are responsible for the observed changes in the type and concentrations of organic matter in the area. Abstract Catalytically active polysaccharides (Cat PSs) and nitrogen-containing polymeric organic material (N-POM) were determined in seawater from the northern Adriatic station ST101. Catalytically active organics were measured by applying electrochemical methods of adsorptive transfer chronopotentiometric stripping with medium exchange and chronopotentiometric stripping in unmodified seawater. Their concentrations were expressed in milligrams per cubic decimetre–3--> of equivalents of the model calibrating substances, polysaccharide xanthan and protein human serum albumin. The optimal electroanalytical conditions for determination of Cat PSs in seawater were evaluated and defined. Seasonal changes of Cat PSs and N-POM were observed during the period 2011–2013. The highest values were determined in the spring–summer period and the lowest in winter. Cat PSs and N-POM were present in both the dissolved and particulate organic carbon fractions. Cat PSs and N-POM showed a statistically significant positive correlation with the concentrations of surface-active substances. A weak but statistically significant correlation was found between Cat PSs and dissolved organic carbon concentrations. Copper complexing capacities in the period 2011–2013 were in the range of 41–130nmoldm–3.
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Kwok, Sun. "Chemical Enrichment of the Solar System by Stellar Ejecta." Proceedings of the International Astronomical Union 10, H16 (August 2012): 161. http://dx.doi.org/10.1017/s174392131400516x.
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AbstractSpectroscopic observations of evolved stars have shown signatures of aromatic and aliphatic compounds. This suggests that complex organics with chemical structures similar to those of insoluble organic matter (IOM) found in carbonaceous meteorites are made in stars. This raises the possibility that in addition to known pre-solar grains such as silicon carbide, organic star dust may also have traveled across the Galaxy to the Solar System.
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Yokouchi, Y., and Y. Ambe. "Characterization of polar organics in airborne particulate matter." Atmospheric Environment (1967) 20, no. 9 (January 1986): 1727–34. http://dx.doi.org/10.1016/0004-6981(86)90121-6.
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Cameron, K. C., H. J. Di, and R. G. McLaren. "Is soil an appropriate dumping ground for our wastes?" Soil Research 35, no. 5 (1997): 995. http://dx.doi.org/10.1071/s96099.
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New Zealand and Australia generate large quantities of agricultural, industrial, and municipal wastes. As authorities move to protect the environment by regulating waste disposal practices, environmentally sound methods of waste disposal are being sought. In particular, land application of wastes as a means of disposal, nutrient re-cycling, and water conservation is becoming increasingly popular. This paper provides an overview of the types, quantities, and characteristics of wastes generated in New Zealand and Australia, and highlights the problems with current waste disposal practices, including landfilling, incineration, and discharging into waters. This is followed by a detailed review of the beneficial effects and adverse impacts of land application of wastes on plant production and soil and environmental quality, and possible hazards to human health. The management of waste application on land is a challenging task and requires rigorous scientific input. Sludges and euents contain significant concentrations of plant nutrients, particularly nitrogen, phosphorus, and organic matter. Their application on land has been shown, in many cases, to result in significant increases in plant yields and improvements in soil physical conditions and chemical fertility. The constraints with some wastes, particularly those of industrial and municipal origin, are that they contain undesirable constituents, e.g. heavy metals, toxic organics, pathogens, and salts, or have extremely high or low pH. High concentrations of nitrate and phosphate derived from wastes are also of concern for ground and surface water contamination. The processes that control the fate of wastes in the soil are complex and many of them are poorly understood, e.g. rate of release of nutrients and other chemicals; leaching of nutrients, metals, and organics through macropores and as suspended solids; emission of greenhouse gases; impact of solvents, surfactants, and sludge organic matter on the sorption, degradation, and leaching of hydrophobic organics; and the long-term bioavailability and fate of metals and organics fixed by soil organic matter. More research is urgently required to develop a sound understanding of waste characteristics and the processes affecting their fate in the soil in order to ensure that land application of wastes is safe.
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Schmidt, P. D., J. E. Tobiason, J. K. Edzwald, and H. Dunn. "DAF treatment of a reservoir water supply: comparison with in-line direct filtration and control of organic matter." Water Science and Technology 31, no. 3-4 (February 1, 1995): 103–11. http://dx.doi.org/10.2166/wst.1995.0521.
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The goal of this paper is to compare the performance of an in-line direct filtration (no flocculation) process with a dissolved air flotation (DAF) and filtration process for drinking water treatment. Both processes were studied at the pilot scale and included biologically active dual media (GAC/sand) rapid filters. Specific attention is given to the fate of organic matter. Organic matter was analyzed by measurements of dissolved organic carbon (DOC), assimilable organic carbon (AOC), disinfection by-product formation potential (DBPFP) and ultraviolet absorbance at 254 nm (UV254). In general, flotation removed a large fraction of organic matter with additional removal provided by biologically active filters. Most of the work occurred with ozonation of the raw water (pre-ozone). Ozone increased the biologically assimilable fraction of the water; filtration decreased this fraction to acceptable levels. Overall, effects of ozone on other organics are relatively small.
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Sharma, S. K., C. M. Harun, and G. Amy. "Framework for assessment of performance of soil aquifer treatment systems." Water Science and Technology 57, no. 6 (March 1, 2008): 941–46. http://dx.doi.org/10.2166/wst.2008.188.
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Removal of organic matter is a critical parameter in soil aquifer treatment (SAT) as it governs and influences the removal of other contaminants by biodegradation namely trace organics, nitrogen species and microbes. A framework for analysis and prediction of the performance of SAT systems with respect to removal of organic matter under different water quality and process conditions was developed based on an extensive literature review and data analysis. Guidelines were developed to make preliminary estimates of the removal of organic matter during SAT using primary, secondary and tertiary effluents from wastewater treatment plants. These guidelines can be used as a quick tool to analyze the performance of existing SAT systems and serve as a decision support tool for feasibility studies and to save time for further detailed experimentation and design of SAT systems. Furthermore, effects of soil type and redox conditions on organic matter removal during SAT were also analyzed.
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Eichler, P., M. Müller, B. D'Anna, and A. Wisthaler. "A novel inlet system for online chemical analysis of semi-volatile submicron particulate matter." Atmospheric Measurement Techniques 8, no. 3 (March 20, 2015): 1353–60. http://dx.doi.org/10.5194/amt-8-1353-2015.
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Abstract. We herein present a novel modular inlet system designed to be coupled to low-pressure gas analyzers for online chemical characterization of semi-volatile submicron particles. The "chemical analysis of aerosol online" (CHARON) inlet consists of a gas-phase denuder for stripping off gas-phase analytes, an aerodynamic lens for particle collimation combined with an inertial sampler for the particle-enriched flow and a thermodesorption unit for particle volatilization prior to chemical analysis. The denuder was measured to remove gas-phase organics with an efficiency > 99.999% and to transmit particles in the 100–750 nm size range with a 75–90% efficiency. The measured average particle enrichment factor in the subsampling flow from the aerodynamic lens was 25.6, which is a factor of 3 lower than the calculated theoretical optimum. We coupled the CHARON inlet to a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS) which quantitatively detects most organic analytes and ammonia. The combined CHARON-PTR-ToF-MS setup is thus capable of measuring both the organic and the ammonium fraction in submicron particles in real time. Individual organic compounds can be detected down to levels of 10–20 ng m−3. Two proof-of-principle studies were carried out for demonstrating the analytical power of this new instrumental setup: (i) oxygenated organics and their partitioning between the gas and the particulate phase were observed from the reaction of limonene with ozone and (ii) nicotine was measured in cigarette smoke particles demonstrating that selected organic target compounds can be detected in submicron particles in real time.
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van Beynen, Philip E., Henry P. Schwarcz, Derek C. Ford, and G. T. Timmins. "Organic substances in cave drip waters: studies from Marengo Cave, Indiana." Canadian Journal of Earth Sciences 39, no. 2 (February 1, 2002): 279–84. http://dx.doi.org/10.1139/e01-072.
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This paper focuses on the flux and characterization of organic substances in cave drip waters for a continental climate. At Marengo Cave in southern Indiana, there is seasonal variations in organic matter concentration in the cave drip water. High levels are introduced during the spring thaw, and lower levels occur during the rest of the year. The fluorescence spectra and ultrafiltration analysis suggest the majority of the organics contained in percolating waters were fulvic acids, with most being less than 1 kDa in size. The seasonal flush of organics from the soil could produce two different types of calcite in the speleothem deposited from these drip waters, a stronger fluorescing calcite during the spring and the less fluorescent calcite during the rest of the year. This is the first study of its type for this particular climatic region.
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Mouchel-Vallon, C., P. Bräuer, M. Camredon, R. Valorso, S. Madronich, H. Herrmann, and B. Aumont. "Explicit modeling of volatile organic compounds partitioning in the atmospheric aqueous phase." Atmospheric Chemistry and Physics Discussions 12, no. 9 (September 14, 2012): 24095–130. http://dx.doi.org/10.5194/acpd-12-24095-2012.
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Abstract. The gas phase oxidation of organic species is a multigenerational process involving a large number of secondary compounds. Most secondary organic species are water-soluble multifunctional oxygenated molecules. The fully explicit chemical mechanism GECKO-A (Generator of Explicit Chemistry and Kinetics of Organics in the Atmosphere) is used to describe the oxidation of organics in the gas phase and their mass transfer to the aqueous phase. The oxidation of three hydrocarbons of atmospheric interest (isoprene, octane and α-pinene) is investigated for various NOx conditions. The simulated oxidative trajectories are examined in a new two dimensional space defined by the mean oxidation state and the solubility. The amount of dissolved organic matter was found to be very low (<2%) under a water content typical of deliquescent aerosols. For cloud water content, 50% (isoprene oxidation) to 70% (octane oxidation) of the carbon atoms are found in the aqueous phase after the removal of the parent hydrocarbons for low NOx conditions. For high NOx conditions, this ratio is only 5% in the isoprene oxidation case, but remains large for α-pinene and octane oxidation cases (40% and 60%, respectively). Although the model does not yet include chemical reactions in the aqueous phase, much of this dissolved organic matter should be processed in cloud drops and modify both oxidation rates and the speciation of organic species.
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Mouchel-Vallon, C., P. Bräuer, M. Camredon, R. Valorso, S. Madronich, H. Herrmann, and B. Aumont. "Explicit modeling of volatile organic compounds partitioning in the atmospheric aqueous phase." Atmospheric Chemistry and Physics 13, no. 2 (January 25, 2013): 1023–37. http://dx.doi.org/10.5194/acp-13-1023-2013.
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Abstract. The gas phase oxidation of organic species is a multigenerational process involving a large number of secondary compounds. Most secondary organic species are water-soluble multifunctional oxygenated molecules. The fully explicit chemical mechanism GECKO-A (Generator of Explicit Chemistry and Kinetics of Organics in the Atmosphere) is used to describe the oxidation of organics in the gas phase and their mass transfer to the aqueous phase. The oxidation of three hydrocarbons of atmospheric interest (isoprene, octane and α-pinene) is investigated for various NOx conditions. The simulated oxidative trajectories are examined in a new two dimensional space defined by the mean oxidation state and the solubility. The amount of dissolved organic matter was found to be very low (yield less than 2% on carbon atom basis) under a water content typical of deliquescent aerosols. For cloud water content, 50% (isoprene oxidation) to 70% (octane oxidation) of the carbon atoms are found in the aqueous phase after the removal of the parent hydrocarbons for low NOx conditions. For high NOx conditions, this ratio is only 5% in the isoprene oxidation case, but remains large for α-pinene and octane oxidation cases (40% and 60%, respectively). Although the model does not yet include chemical reactions in the aqueous phase, much of this dissolved organic matter should be processed in cloud drops and modify both oxidation rates and the speciation of organic species.
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Schäfer, A. I., A. G. Fane, and T. D. Waite. "Direct coagulation pretreatment in nanofiltration of waters rich in organic matter and calcium." Water Supply 1, no. 4 (June 1, 2001): 25–33. http://dx.doi.org/10.2166/ws.2001.0063.
Full textAbstract:
Nanofiltration (NF) can remove natural organic matter (NOM) and multivalent ions from surface waters. Large hydrophobic organics and calcium ions are responsible for irreversible fouling of nanofiltration membranes and thus a decrease of process efficiency and increase in cleaning requirements. Fouling due to the precipitation of organic-calcium complexes and the impact of colloids and coagulant (FeCl3) on the precipitation of these species was investigated. Coagulation in solution (as opposed to in the boundary layer) did not cause significant flux decline and was able to prevent irreversible fouling under conditions which were previously determined as detrimental. The rejection was varied if a strongly charged solid was deposited on the membrane.
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Fuentes, E., H. Coe, D. Green, G. de Leeuw, and G. McFiggans. "On the impacts of phytoplankton-derived organic matter on the properties of the primary marine aerosol – Part 1: Source fluxes." Atmospheric Chemistry and Physics 10, no. 19 (October 1, 2010): 9295–317. http://dx.doi.org/10.5194/acp-10-9295-2010.
Full textAbstract:
Abstract. The effect of biogenic dissolved and colloidal organic matter on the production of submicron primary sea-spray aerosol was investigated via the simulation of bubble bursting in seawater enriched with phytoplankton-released organics. Seawater samples collected along a transect off the West African coast during the RHaMBLe cruise (RRS Discovery cruise D319), conducted as part of the SOLAS UK program, were analysed in order to identify the dominant oceanic algal species in a region of high biological activity. Cultures of microalgal strains representative of the species found in the collected seawater were grown in order to produce natural bioexudate. Colloidal plus dissolved organic fraction in this material remaining after <0.2 μm filtration was employed to prepare organic-enriched seawater proxies for the laboratory production of marine aerosol using a plunging-waterjet system as an aerosol generator. Submicron size distributions of aerosols generated from different organic monolayers and seawater proxies enriched with biogenic exudate were measured and compared with blanks performed with artificial seawater devoid of marine organics. A shift of the aerosol submicron size distribution toward smaller sizes and an increase in the production of particles with dry diameter (Dp0)<100 nm was repeatedly observed with increasing amounts of diatomaceous bioexudate in the seawater proxies used for aerosol generation. The effect was found to be sensitive to the organic carbon concentration in seawater and the algal exudate type. Diatomaceous exudate with organic carbon concentration (OC<0.2 μm) >175 μM was required to observe a significant impact on the size distribution, which implies that effects are expected to be substantial only in high biological activity areas abundant with diatom algal populations. The laboratory findings were in agreement with analogous bubble-bursting experiments conducted with unfiltered oceanic seawater collected during the RHaMBLe cruise, which revealed a higher production of particles with Dp0<100 nm at regions with high biological activity. These findings suggest that the increase in the atmospheric aerosol modal sizes from winter to summer, reported by long-term observations in North Atlantic waters, is not directly due to an impact of the higher primary organic matter production occurring during warm periods. A novel sub-micrometric size-resolved source flux function, explicitly defined as a function of the diatomaceous exudate concentration, was derived from the size distribution measurements and the estimation of the fractional whitecap coverage. According to the defined parameterisation, a 300 μM OC<0.2 μm concentration of diatomaceous exudate in seawater produces an overall increment in the total source particle flux of ~20% with respect to the organics-free seawater case. The effect increases with decreasing particle size for Dp0<100 nm, resulting in multiplicative factors between 1.02–2 with respect to the particle flux generated from seawater devoid of marine organics. The total source flux derived from the presented parameterisation was compared to recent definitions of sea-spray source fluxes based on laboratory and field observations in the literature.
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Bayne, B. L., J. I. P. Iglesias, A. J. S. Hawkins, E. Navarro, M. Heral, and J. M. Deslous-Paoli. "Feeding behaviour of the mussel, Mytilus edulis: responses to variations in quantity and organic content of the seston." Journal of the Marine Biological Association of the United Kingdom 73, no. 4 (November 1993): 813–29. http://dx.doi.org/10.1017/s0025315400034743.
Full textAbstract:
Mussels were fed four concentrations of seston (between 0·99 and 10·3 mg total seston I−1), comprising three levels of organic content (71·9, 63·6 and 40·8%), made up from natural silt and two species of cultured phytoplankton. Two of the seston concentrations were below, and two above, the threshold at which pseudofaeces were produced. Measurements of physiological traits (filtration rates, pseudofaeces production, selection efficiency, absorption efficiency, absorption rates and rates of oxygen consumption) were made after 2 days and, for two of the seston concentrations, also after 12 days. When fed at a high concentration of seston of low organic content, the mussels increased their filtration rate, rejected a higher proportion of filtered material as pseudofaeces, and increased the efficiency with which filtered matter of higher organic content was selected for ingestion; this resulted in a constancy of the relationship between ingestion rate and the concentration of particulate organic matter, regardless of differences in seston organic content. Between 2 and 12 d, the mussels increased absorption rates for organics, primarily by increasing absorption efficiency, both for total organics and for the carbohydrate component of the diet. We suggest that these responses to changes in the food environment comprise physiological adjustments which result in higher net rates of absorption than would be predicted from considerations only of the organic/inorganic ratio of the suspended particles and assumptions of a non-compensating feeding behaviour.