ENERGY REQUIREMENTS AND EFFICIENCY

Theoretically, the energy, E, required to generate droplets from a liquid or melt can be roughly estimated by that needed to create the surface area of droplets, i.e., the product of the surface area of droplets and the surface tension of the liquid  

Neglecting the energy for overcoming viscous force during liquid breakup, a simple equation for the theoretical energy efficiency has been derived by Yule and Dunkleyl5 for a pressure-swirl atomizer  

Detailed descriptions of the practical aspects of atomizer performance, plant design, and operation for powder productionthrough atomization of liquid metals have been given by Yule and Dunkley 

The subject of liquid jet and sheet atomization has attracted considerable attention in theoretical studies and numerical modeling due to its practical importance.[527] The models and methods developed range from linear stability models to detailed nonlinear numerical models based on boundary-element methods 528 5291 and Volume-Of-Fluid (VOF) method. 530  

Alternative methods of analysis have been examined and evaluated. Shokoohi and Elrod[533] solved the Navier-Stokes equations numerically in the axisymmetric form. Bogy15271 used the Cosserat theory developed by Green.[534] Ibrahim and Linl535 conducted a weakly nonlinear instability analysis. The method of strained coordinates was also examined. In spite of the mathematical or computational elegance, all of these methods suffer from inherent complexity. Lee15361 developed a 1 -D, nonlinear direct-simulation technique that proved to be a simple and practical method for investigating the nonlinear instability of a liquid j et. Lee s direct-simulation approach formed the 

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Steen, R.W.J., L.E.R. Dawson, D.E. Kirkpatrick, and S.D. Johnston, 1997. Estimation of maintenance energy requirements and efficiency of utilization of metabolizable energy for growth in lambs by indirect calorimetry and comparative slaughter. In McCracken, K., Unsworth, E.E, and A.R.G. Wylie (eds.). Energy metabolsim of farm animals. CAB Inbtemationa, Wallingford, UK 351-354. 

For certain applications, such as the separation of ternary mixtures, divided wall columns may be of interest, [9] which have shown to reduce the energy requirements and increase exergy efficiency. 

The efficiency of cluster impact in driving four-center reactions is due to a matching between what the cluster can do to the reactants or products and the very selective energy requirements and the specific energy disposal in a concerted reactive collision, as discussed in details in Sec. 3.2. The cluster serves to provide both the steric and energetic conditions necessary for this reaction. In terms of the impact parameter of the relative motion of the two reactants, their confinement by the cluster keeps it low, so that they do not miss one another. This confinement within the cluster favoring low impact parameter collisions is a key ingredient in why such processes are so efficient. Furthermore, both the activation of the reactants before the reaction and the stabilization of the hot product after it, are due to the cluster atoms. 

Based upon the analysis developed in this paper, the indirectly heated system can obtain approximately 45% PSU with mole percent H20 equal to 40% as shown in Fig. 10. From Fig. 13 we see that this PSU brings the process into the range of minimum energy requirements and therefore maximum thermal efficiency. On this basis we have recommended further research and development of indirectly heated reactors for the production of activated carbon from municipal solid waste and biomass. 

Increase energy efficiency, recognize the environmental and economic impacts of energy requirements and minimize them by conducting chemical reactions at ambient temperature and pressure whenever possible. 

Membrane Process for Recovery of Alkanesulfonates. Many attempts have been made over the years to reduce the wastewater load—which represents a loss of product—by a number of different methods. These include evaporation, extraction, reverse osmosis, and ultrafiltration. All of these processes have the disadvantage of high equipment cost and high energy requirements, and the space-time yield is low. The first breakthrough came with the development of new types of membrane with a definite separating efficiency and a large surface area, so-called spiral-wound modules. 

Weighted Average Annual Energy Requirements and Drying Efficiency for Industrial Solid Dryers— Based on Surveyed Data... 

Regardless of whether a net availability of heat or work is transferred to or from a process, the energy balance must be satisfied. Thus, the energy and availability balances are used together to determine energy requirements and irreversibilities that lead to lost work. The more efficient a process, the smaller the lost work. 

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