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Carbon Spheres for the Removal of Hevay Metal Ions From Refinery Effluents
Get PDFAn environmentally-friendly hydrothermal procedure was employed to synthesize carbon spheres (CS) from glucose solution at 1700C. To study the effect of reaction time, four CS samples were synthesized at 12h, 14h, 16h and 19h, respectively. A portion of the samples were surface activated by the treatment with 0.5M NaOH, the other portion treated with 0.5M CH3COOH, and the remaining samples were left untreated (native). All samples were characterized using various methods including SEM, XRD, Raman spectroscopy, N2 adsorption and FT-IR. Batch adsorption experiments were carried out at room temperature to remove heavy metal ions (Ag+ and Cu2+) from aqueous solution. It was found that increasing reaction time resulted in CS with a lower amorphous content and lowered adsorption capacity, NaOH-treated CS had the highest adsorption capacity of 454 mg Ag+/g and 172 mg Cu2+/g, while CH3COOH-treated CS had a lower Ag+ and Cu2+ uptake than untreated CS. The adsorption isotherms were well fit by the Langmuir isotherm equation (for base-treated CS) and the Freundlich isotherm equation (for acid-treated CS). The CS showed a high potential for the removal of heavy-metals from aqueous solutions
Entransy Analysis of an Irreversible Diesel Cycle
Get PDFThe purpose of this paper is to research an irreversible Diesel cycle by using entransy approach. Entransy may be expressed as heat transfer potential of a subject and it has begun to investigate as a new thermodynamic assessment parameter. Optimization of heat transfer processes is very important, because of their extensity. Result of optimizing heat transfer is to use energy efficiently and decrease CO2 emission that is main reason of the global warming. Because of the these reasons, entransy analysis of a Diesel cycle is investigated and result are presented. Some obtained results for entransy analysis are: entransy efficiency has minimum (0.191) at x = 19.296, has a maximum (1.538x106 kW K) at x = 8.316 for ηE = ηC = 1. cycle and has a maximum point at x = 6.959 and it value is 1.341x106 kW K for ηE = ηC = 0.8
Penecontemporaneous Deformational Structures in the Glauconitic Sandstone, Semri Group (Vindhyan Supergroup), Sonbhadra District, Uttar Pradesh, India and their Structural Analysis
Get PDFThe Glauconitic sandstone is well exposed in the Newari area of Sonbhadra district of Uttar Pradesh, India. Conjugate pairs of kink bands are confined within the laminated sandstone and are present half km west of Newari near the confluence of a tributary with the Son river. The conjugate kink bands are plunging at 130 and 360 in SE (S580E) and NE (N560E). This shows that ephemeral compressional stress regime was responsible for the development of conjugate set of kink bands. The stress axis would have been oriented from NE-SW direction. A major fault F1 passes through the glauconitic sandstone in the west of the Newari village. This fault is a reverse fault and strikes at N25ºW - S25ºE. Another fault F2 oblique to F1 passes in the direction N70ºE-S70ºW. In view of the fact that the kink bands are confined within the laminated sandstone, it is inferred that they have been formed as a result of penecontemporaneous deformation and suggest seismic activities that might have occurred around 1080±40 Ma ago as a result of activation of the faults present in the Newari area of the Sonbhadra district, Uttar Pradesh, India those may be companion faults of the Son-Narmada Fault system
The Thixotropic Hardening Behaviour of a Low Plasticity Dredged Marine Silt
Get PDFAn alternative to solve the problem of disposing dredged marine sediments (DMS) in open sea, which could lead to undesirable contamination and destruction of the marine ecosystem, is to reuse the material in reclamation works. For such applications, it is important to determine the time required for strength gain of the relocated DMS. A lab-based study was conducted to simulate and examine the post-consolidation hardening of DMS when placed as a backfill with relation to time. A separate series of tests were also carried out on the DMS being lightly solidified with cement, with the purpose of identifying potential shortening of the waiting period. The DMS sample was prepared at different water contents based on the soil's liquid limit (LL = 54.5 %), i.e. 0.90, 1.25 and 1.81LL. The undrained shear strength was measured using the laboratory vane shear (VS) test. Complementary fall cone (FC) tests were conducted for additional information on the improved remoulded strength and stiffness of the DMS. The results showed that the strength and stiffness (cone penetration resistance) of the relocated DMS could effectively improve with time, though the rest period required is shorter for a sample with lower initial water content. On the other and, light cementation shortened the rest period, and significantly improved the strength and stiffness at dosages as low as 5 % (as per dry weight of the soil). Overall the study gave an overview of the reusability of DMS as a backfill material in reclamation works, whether with or without lightly induced solidification, depending mainly on the limitations of rest period available
Did you Ask for the Importance of Investigations Concerning the Chain of a Sustainable Petroleum and Oil Exploration, Production, Flow, and Fast Optimal Refining Technology?
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The Methodological Aspect of Development and Application Multivariate Classification G-Mode for Analyses Geochemical Trend
Get PDFThis article is unique G-mode of multidimensional classification method and its application in the analysis of hydrogeochemistry Donetsk basin. He has the following main advantages over other methods of classification: does not require a priori information for classification of observations; earmarks homogeneous observing classes and subclasses; evaluates information weight of each indicator, determines the distance between the homogeneous taxon's; assessment of the descriptiveness of the sign of the classification and others. G-method is widely used to analyze geochemical, environmental, kosmochemical, distance and other types of information. The method successfully used in examining objects, phenomena and processes on Earth, Moon, Mars, Saturn, comets, asteroids and deep space. The results of the use of G-method in analysis of hydrogeological data for the Donetsk basin identified direct and inverse geochemical zonality. This shows that in the region can be discovered oil and gas accumulations
On Special Strong Differential Superordinations Using Sălăgean and Ruscheweyh Operators
Get PDFIn the present paper we obtain strong differential superordinations for the differential operator defined as a convex combination of the extended Sălăgean operator and the extended Ruscheweyh derivative, and is the class of normalized analytic functions, the extended Ruscheweyh derivative, the extended Sălăgean operator
Numerical Pattern of 3D Tornado Rise with Account for Mirror Asymmetry
Get PDFAuthors are returning to the basic concepts of turbulence – homogeneity and symmetry principles. It is shown that the homogeneity in the sense of constant mean velocity gradient (instead of constant velocity) permits to introduce mirror asymmetry. This way is corresponding to stratified atmosphere and to differential volume in any continuum model. The basic ideas of A. N. Kolmogorov do not contradict to such an approach. Moreover, the use of the intrinsic eddy angular velocity (so-called spin or mesovorticity) as the internal thermodynamic parameter becomes necessary for adequate description of tornado (and intensive atmospheric vortices, in general) dynamics. The continuum description is formulated with standard introducing of stresses averaged over a cross-section, and now motivated asymmetry leads to the vortices moment of momentum balance. The set of nonlinear 3D partial differential equations is suggested for the problem of tornado generation from a cloud of initial vortices. The dependence of turbulent rotation viscosity on the spin permits to localize the tornado body due to the nonlinear diffusion effect. Numerical calculations are performed at two different clusters using Parjava program environment. The growth of typical tornado structure is shown by a sequence of pictures. A visual comparison with the Hurricane Isabel, 2003, is represented
Analytical and Comparative Study of a Mini Solar-Powered Cogeneration Unit Based on Organic Rankine cycle for Low-Temperature Applications
Get PDFIn this paper, we analyze characteristics of a small Combined Heat and Power (CHP) system based mainly on Organic Rankine Cycle (ORC) and heating plant in actual series connection regarding the low-temperature heat carrier heated by purely solar flat collector field. Simultaneously and for specific power production, comparison of this layout with stand-alone ORC, and with the traditional ORC-CHP imposing gain of condenser heat for heating aims, in second step, has been conducted. For evaluation, energetic and design criteria have been determined opposite the heating effects and also temperatures of the heat source and sink. The simulations addressed interesting optimization ratios till 24 % for the power unit throughout this series CHP utility versus single power generation at the same conditions tested. Moreover, the high heat source temperatures and CHP ratios improve the performance of the overall series plant, while the high supply and return temperatures have negative effects. Finally, the ORC-CHP scheme handled here highlights distinctive exploitation aspects and more suitability in wide range of application in comparison to yielding the high-temperature condensation heat of ORC, especially at low ambient temperatures, high supply and heat source temperatures. So, it can be advised to be adopted instead of the two other strategies