scholarly journals Biological control and management of the detoxication wastewater treatment technologies

2007 ◽  
Vol 61 (5) ◽  
pp. 213-221 ◽  
Author(s):  
Yana Topalova
Keyword(s):  
Water Pollution ◽  
Electron Microscopy ◽  
Wastewater Treatment ◽  
Practical Knowledge ◽  
Pilot Scale ◽  
Scale Modeling ◽  
Transmission Electron ◽  
Treatment Technologies ◽  
Control And Management ◽  
Xenobiotic Biodegradation

Detoxication technologies require the combination of theoretical and practical knowledge of xenobiotic biodegradation, wastewater treatment technologies, and management rules. The purpose of this complicated combination is to propose specialized strategies for detoxication, based on lab- and pilot-scale modeling. These strategies include preliminary created algorithms for preventing the risk of water pollution and sediments. The technologies and algorithms are essentially important outcome, applied in the textile, pharmaceutical, cosmetic, woodtreating, and oiltreating industries. In this paper four rehabilitation technologies for pretreatment of water contaminated by pentachlorophenol (PCP) have been developed in the frame of the European and Bulgarian National projects. Emphasize is put on the biological systems and their potential of detoxication management. The light and transmission electron microscopy of the reconstructed activated sludges the microbial, kinetic and enzymological indicators are presented and approved as critical points in the biocontrol.

Linear, non-linear and plastic bending deformation of cellulose nanocrystals

2016 ◽  
Vol 18 (29) ◽  
pp. 19880-19887 ◽  
Author(s):  
Pan Chen ◽  
Yu Ogawa ◽  
Yoshiharu Nishiyama ◽  
Ahmed E. Ismail ◽  
Karim Mazeau
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Cellulose Nanocrystals ◽  
Deformation Behavior ◽  
Plastic Bending ◽  
Bending Deformation ◽  
Multi Scale ◽  
Scale Modeling ◽  
Transmission Electron ◽  
Multi Scale Modeling

Bending deformation of cellulose nanocrystal is investigated by using multi-scale modeling and transmission electron microscopy, which highlights importance of shear contribution in the deformation behavior of cellulose.

scholarly journals Carbon-Based Nanocomposites as Fenton-Like Catalysts in Wastewater Treatment Applications: A Review

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2643
Author(s):  
Ling Xin ◽  
Jiwei Hu ◽  
Yiqiu Xiang ◽  
Caifang Li ◽  
Liya Fu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Wastewater Treatment ◽  
Free Radicals ◽  
Organic Pollutants ◽  
Transition Metal Ions ◽  
Future Research ◽  
Hydroxyl Groups ◽  
Edge Structure ◽  
Transmission Electron

Advanced oxidation (e.g., fenton-like reagent oxidation and ozone oxidation) is a highly important technology that uses strong oxidizing free radicals to degrade organic pollutants and mineralize them. The fenton-like reactions have the characteristics of low cost, simple operation, thorough reaction and no secondary pollution. Fenton-like reagents refer to a strong oxidation system composed of transition metal ions (e.g., Fe3+, Mn2+ and Ag+) and oxidants (hydrogen peroxide, potassium persulfate, sodium persulfate, etc). Graphene and carbon nanotube possess a distinctive mechanical strength, flexibility, electrical and thermal conductivity and a very large specific surface area, which can work as an excellent carrier to disperse the catalyst and prevent its agglomeration. Fullerene can synergize with iron-based materials to promote the reaction of hydroxyl groups with organic pollutants and enhance the catalytic effect. Fenton-like catalysts influence the catalytic behavior by inducing electron transfer under strong interactions with the support. Due to the short lifespan of free radicals, the treatment effect is usually enhanced with the assistance of external conditions (ultraviolet and electric fields) to expand the application of fenton-like catalysts in water treatment. There are mainly light-fenton, electro-fenton and photoelectric-fenton methods. Fenton-like catalysts can be prepared by hydrothermal method, impregnation and coordination-precipitation approaches. The structures and properties of the catalysts are characterized by a variety of techniques, such as high-resolution transmission electron microscopy, high-angle annular dark-field scanning transmission electron microscopy and X-ray absorption near-edge structure spectroscopy. In this paper, we review the mechanisms, preparation methods, characterizations and applications status of fenton-like reagents in industrial wastewater treatment, and summarize the recycling of these catalysts and describe prospects for their future research directions.

scholarly journals Hydrologic System Protection by Decentralized Wastewater Treatment Technologies in Jordan

2019 ◽  
Vol 3 (1) ◽  
pp. 19-27
Author(s):  
Naser Almanaseer
Keyword(s):  
Wastewater Treatment ◽  
Pilot Scale ◽  
Jordan Valley ◽  
Experimental Site ◽  
E Coli ◽  
System Protection ◽  
Decentralized Wastewater Treatment ◽  
Hydrologic System ◽  
Treatment Technologies ◽  
Removal Efficiencies

The nine different technologies are constructed at the pilot scale in one experimental site at Al-Balqa Applied University and use the same wastewater characteristics as the inlet. Monthly samples were collected from the inlet and outlet of nine different decentralized wastewater treatment technologies for three years (June 2016-June 2019). The samples were analyzed for physical, chemical, and biological parameters including TSS, Turbidity, pH, COD, DO, NH4, NO3, TN, BOD, and E. coli. Removal efficiencies for the nine technologies are obtained for COD, BOD, TN, and TSS to be above 95%. NH4 the removal efficiencies for the nine technologies vary and found to be in the range of 27 to 76% while for the E. coli in the range of 65 to 95%. Further, data on energy consumption were collected for each technology and found for the nine investigated technologies in the range of 0.03 to 0.30 Jordan Dinars per treated cubic meter. The investigated technologies were evaluated, and the best options were endorsed. It is concluded that the adaptation of decentralized wastewater treatment will certainly help protect the hydrologic system in Jordan especially in the high lands where significant groundwater recharge occurs and a considerable amount of surface water flows towards Jordan Valley and collection dams.

Economic feasibility study for new technological alternatives in wastewater treatment processes: a review

2012 ◽  
Vol 65 (5) ◽  
pp. 898-906 ◽  
Author(s):  
María Molinos-Senante ◽  
Francesc Hernández-Sancho ◽  
Ramón Sala-Garrido
Keyword(s):  
Wastewater Treatment ◽  
New Technologies ◽  
Shadow Price ◽  
Methodological Approach ◽  
Market Price ◽  
Feasibility Studies ◽  
Pilot Scale ◽  
Economic Feasibility ◽  
Environmental Benefits ◽  
Treatment Technologies

The concept of sustainability involves the integration of economic, environmental, and social aspects and this also applies in the field of wastewater treatment. Economic feasibility studies are a key tool for selecting the most appropriate option from a set of technological proposals. Moreover, these studies are needed to assess the viability of transferring new technologies from pilot-scale to full-scale. In traditional economic feasibility studies, the benefits that have no market price, such as environmental benefits, are not considered and are therefore underestimated. To overcome this limitation, we propose a new methodology to assess the economic viability of wastewater treatment technologies that considers internal and external impacts. The estimation of the costs is based on the use of cost functions. To quantify the environmental benefits from wastewater treatment, the distance function methodology is proposed to estimate the shadow price of each pollutant removed in the wastewater treatment. The application of this methodological approach by decision makers enables the calculation of the true costs and benefits associated with each alternative technology. The proposed methodology is presented as a useful tool to support decision making.

Japanese experiences in water pollution control and wastewater treatment technologies

2000 ◽  
Vol 42 (12) ◽  
pp. 163-172 ◽  
Author(s):  
T. Matsuo
Keyword(s):  
Water Pollution ◽  
Environmental Management ◽  
Wastewater Treatment ◽  
Life Cycle Assessment ◽  
Pollution Control ◽  
Industrial Pollution ◽  
Environmental Legislation ◽  
Water Pollution Control ◽  
History Of ◽  
Treatment Technologies

The history of water pollution control and environmental management in Japan is outlined. Particular attention is paid to Minamata disease and other impacts of industrial pollution, and the consequent development of environmental legislation. The growth of sewerage systems and more recently of wastewater and sludge reuse are noted, before considering the application of the concept of life cycle assessment, which is increasingly central to the minimisation of environmental impacts.

Evaluating upgrade possibilities of activated sludge wastewater treatment plants utilizing biofilm-based treatment technologies – an experimental study at the South Pest WWTP

2012 ◽  
Vol 7 (1) ◽  
Author(s):  
N. Szilágyi ◽  
R. Kovács ◽  
I. Kenyeres ◽  
B. Törő ◽  
Zs. Csikor ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Plant Root ◽  
Pilot Scale ◽  
Load Reduction ◽  
The South ◽  
Treatment Technologies ◽  
Biofilm Carriers

As more and more wastewater treatment plants (WWTPs) arrive to a point in their lifecycles when their original capacities are not sufficient anymore, the demand for good WWTP retrofitting solutions becomes increasingly critical. One of the typical problems is the suspended solids overload of secondary clarifiers, which is one of the main concerns at the South Pest WWTP as well. Pilot scale studies were carried out at the WWTP with a biofilm based technology applying biofilm carriers imitating plant root structures in order to characterize the potentials of clarifier TSS load reduction while maintaining the existing biodegradation performance of the activated sludge stage. The research demonstrated that the clarifier load can be reduced by more than 90%, while the original biodegradation performance of the system does not decrease. In addition to this, it was demonstrated that the biomass amount in the reactors can be increased substantially opening potentials for further biodegradation capacity.

Techniques for Transmission Electron Microscopy of Fiber-Matrix Interfaces in Aluminum Alloy-Boron Composites by Ion Erosio

1971 ◽  
Vol 29 ◽  
pp. 204-205
Author(s):  
G. G. Shaw
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Aluminum Alloy ◽  
Electron Beam ◽  
Pure Aluminum ◽  
Ion Milling ◽  
Transmission Electron ◽  
Fiber Matrix ◽  
Ion Erosion ◽  
Row Of Fibers

The morphology and composition of the fiber-matrix interface can best be studied by transmission electron microscopy and electron diffraction. For some composites satisfactory samples can be prepared by electropolishing. For others such as aluminum alloy-boron composites ion erosion is necessary.When one wishes to examine a specimen with the electron beam perpendicular to the fiber, preparation is as follows: A 1/8 in. disk is cut from the sample with a cylindrical tool by spark machining. Thin slices, 5 mils thick, containing one row of fibers, are then, spark-machined from the disk. After spark machining, the slice is carefully polished with diamond paste until the row of fibers is exposed on each side, as shown in Figure 1.In the case where examination is desired with the electron beam parallel to the fiber, preparation is as follows: Experimental composites are usually 50 mils or less in thickness so an auxiliary holder is necessary during ion milling and for easy transfer to the electron microscope. This holder is pure aluminum sheet, 3 mils thick.

Direct Observation of Heat Exchanger Deposits by Cross Sectioning

1967 ◽  
Vol 25 ◽  
pp. 364-365
Author(s):  
R. W. Anderson ◽  
D. L. Senecal
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Heat Exchanger ◽  
Direct Observation ◽  
Cross Sections ◽  
Preparation Method ◽  
Specimen Preparation ◽  
Flowing Water ◽  
Transmission Electron ◽  
Deposit Layer

A problem was presented to observe the packing densities of deposits of sub-micron corrosion product particles. The deposits were 5-100 mils thick and had formed on the inside surfaces of 3/8 inch diameter Zircaloy-2 heat exchanger tubes. The particles were iron oxides deposited from flowing water and consequently were only weakly bonded. Particular care was required during handling to preserve the original formations of the deposits. The specimen preparation method described below allowed direct observation of cross sections of the deposit layers by transmission electron microscopy.The specimens were short sections of the tubes (about 3 inches long) that were carefully cut from the systems. The insides of the tube sections were first coated with a thin layer of a fluid epoxy resin by dipping. This coating served to impregnate the deposit layer as well as to protect the layer if subsequent handling were required.

Phase Transformations in Ti-7w/oMo-3w/oMe Alloy

1974 ◽  
Vol 32 ◽  
pp. 514-515
Author(s):  
S. Fujishiro
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Transmission Electron Microscopy ◽  
Tensile Strength ◽  
Mechanical Processing ◽  
Ray Method ◽  
X Ray ◽  
Transmission Electron ◽  
Water Quench ◽  
Alpha Beta

The mechanical properties of three titanium alloys (Ti-7Mo-3Al, Ti-7Mo- 3Cu and Ti-7Mo-3Ta) were evaluated as function of: 1) Solutionizing in the beta field and aging, 2) Thermal Mechanical Processing in the beta field and aging, 3) Solutionizing in the alpha + beta field and aging. The samples were isothermally aged in the temperature range 300° to 700*C for 4 to 24 hours, followed by a water quench. Transmission electron microscopy and X-ray method were used to identify the phase formed. All three alloys solutionized at 1050°C (beta field) transformed to martensitic alpha (alpha prime) upon being water quenched. Despite this heavily strained alpha prime, which is characterized by microtwins the tensile strength of the as-quenched alloys is relatively low and the elongation is as high as 30%.

Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

1977 ◽  
Vol 35 ◽  
pp. 638-639
Author(s):  
P.J. Dailey
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Salivary Glands ◽  
Secretory Vesicles ◽  
The Past ◽  
Transmission Electron ◽  
Means Of Transmission ◽  
Gromphadorhina Portentosa ◽  
Scanning Electron ◽  
Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

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