GRAPHICAL SOLUTION OF MULTISTAGE FLUIDIZED BED HEAT EXCHANGER

The design of multistage fluidized beds for heat exchange necessitates the solution of the mass and energy balance equations combined with the equilibrium relations for each stage. This paper presents a novel way of applying well known methodology to a different technology, one where it has not been widely applied.

In the present work a McCabe-Thiele type of graphical approach is presented for both counter-current and cross-current contacting multiple fluidized beds. The necessary equations for a multistage calciner are developed and the application of the proposed method is demonstrated. Generalized fluidized bed efficiency for counter-current and cross-current multiple fluidized bed is presented.     

DISTILLATION COLUMN DESIGN BY METHOD OF McCABE AND THIELE: DISTMAN COMPUTER GRAPHICS PROGRAM

A computer graphics program developed for the IBM PC calculates equilibrium and operating lines and steps off the number of stages on screen using the McCabe-Thiele method. The results are obtained by graphics, not by numerical methods, so that the accuracy depends upon the screen resolution or pixel density. The equilibrium line is drawn from bubble-point temperature calculations using constants from the Wilson and Antoine equations. The operating lines and staircase are constructed by computer graphics according to the prescribed operating parameters. Design variables, which include the reflux ratio, quality of feed, Murphree efficiency, product purities and pressure, may be changed interactively.     

A RIGOROUS ANALYSIS OF McCABE-THIELE ASSUMPTIONS AND THEIR CONSEQUENCES: CRITICAL ROLE OF PARALLEL ENTHALPY LINES

The assumptions and results associated with the McCabe-Thiele method of distillation column analysis are brought together within a rigorous analytical framework. Within this framework, the assumption that the saturated liquid and vapor enthalpy curves are parallel lines, apart from adiabatic and isobaric operation of the distillation column, is shown to be sufficient to derive all the major results of the McCabe-Thiele method including the constant molar overflow condition. Then, using a rigorous thermodynamic analysis, a comprehensive set of conditions sufficient for the enthalpy curves to be parallel lines are obtained. Some common systems for which these assumptions hold are discussed. Finally, the conditions under which McCabe-Thiele-like methods occur in other separation processes are outlined, with pointers to a unified picture of separation processes.     

云南某氧化铜矿氨浸液萃取工艺

以云南某氧化铜矿的氨浸液作为萃取原液,研究萃取-洗涤-反萃过程。用McCabe-Thiele等温线法,推算二级萃取和一级反萃过程中各产物含铜浓度的变化。采用分流萃取的工艺,可以避免返回使用的萃余液被稀释。对含氨量测定表明,氨浸-萃取体系的氨挥发量和水膨胀均可控制。     

Origin LabTalk在精馏实验教学中的应用

开发了一种使用Origin软件对精馏实验数据进行图解法处理的方法,以苯——甲苯混合液实验体系为例,对实验数据进行处理,通过LabTalk脚本语言绘制出梯级图,以图解法分别求解出实验所需理论塔板数和加料板位置。结果表明该方法具有方便、快捷、准确性高的特点,并且可以有效提高学生的计算机数据处理能力。     

Solvent extraction and separation of Y(III) from sulfate,nitrate and chloride solutions using PC88A diluted in kerosene

Solvent extraction of yttrium (Y) from different aqueous solutions using the organic extractant 2- ethylhexyl phosphonic acid mono-2-ethylhexyl ester (PC88A) diluted in kerosene was investigated. Solution chemistry considerations were proposed to identify the predominant species in different aqueous media (H₂SO₄, HCl and HNO₃). In general, nitric and hydrochloric acids were found to be more efficient than sulfuric acid for yttrium extraction. Separation studies showed that nitric acid provide higher separation of Y(III) from light REES while sulfuric acid works better when separation of Y(III) from heavy REEs is desired.     

DYNAMIC EFFECTS OF BUBBLE MOTION

The dynamic effects of the motion of single bubbles entrained in a liquid are investigated. Extensive original experimental results are presented on the pressures associated with the motion of large, isolated spherical cap air bubbles rising both freely and through constricting orifices in a vertical cylindrical pipe filled with quiescent water. The pressures, measured at the pipe wall, were found to be as high as the dynamic bubble pressure for translational bubble motion, and an order of magnitude larger for oscillatory bubble motion following bubble formation.     

GRAPHICAL SOLUTION OF MULTISTAGE FLUIDIZED BED HEAT EXCHANGER

The design of multistage fluidized beds for heat exchange necessitates the solution of the mass and energy balance equations combined with the equilibrium relations for each stage. This paper presents a novel way of applying well known methodology to a different technology, one where it has not been widely applied.

In the present work a McCabe-Thiele type of graphical approach is presented for both counter-current and cross-current contacting multiple fluidized beds. The necessary equations for a multistage calciner are developed and the application of the proposed method is demonstrated. Generalized fluidized bed efficiency for counter-current and cross-current multiple fluidized bed is presented.