Continuous filtration/expression

Continuing with question 1, develop an expression for the initial filtration rate per unit area of filtration. 

The model proposed above is analogous to a continuous, unsteady state filtration process, and therefore may be called "Filtration Model". In this model, the concentration of the filtrate, viz. the concentration of the solute remained in the treated solid is one s major concern. This is given by the rate of Step 3, which may be expressed by an equation similar to Pick s Law including a transmission coefficient D for the porous medium, viz. the P.S.Z. and the concentration difference Aw across the P.S.Z. as the driving force, and the thickness of the P.S.Z. as the distance Ax. 

During filtration, as the particulate buildup continues on the filtration medium, the filtration resistance increases, or in other words, the filtration permeability decreases. The capacity of a system, expressed in time, volume of liquid fed, or amount of solids fed, depends on the ability of the system to maintain acceptable permeability. 

Obtained by solvent extraction using petroleum hydrocarbons, or to a lesser extent by expression using continuous screw-press operations, of the seeds of either Glycine max (Leguminosae) or Glycine soja (Leguminosae). The oil is refined, deodorized, and clarified by filtration at about 0°C. Any phospholipids or sterols present are removed by refining with alkali. 

Expression. Both sedimentation and filtration are suitable separation techniques when the mixture of liquid and solids is sufficiently mobile to allow pumping, or similar method of motion, of the fluid to a barrier which retains the solid but not the liquid. If such movement is not possible then separation can be accomplished by compressing the mixture under conditions which permit the liquid to escape while retaining the solid between the compressing surfaces. This technique is called expression. Design of expression equipment is varied. Batch systems usually operate by the application of hydraulic pressure in units such as the box press, pot press, curb press and cage press. Continuous expression utilises equipment such as screw presses, roller mills, and belt presses [23]. 

Although comprehensive descriptions of equipment selection are given in this chapter the specifics of data analysis and equipment simulation are presented elsewhere. Chapter 4 provides practical methodologies, theories and principles that underpin the analysis of filtration, jar sedimentation and expression tests. Chapters 6 and 7 respectively present extensive descriptions of batch and continuous filter simulations, however, an introduction to simulation is described here. 

The fundamental equations describing the particle retention behavior in a deep-bed filtration are the continuity equation, the rate equation, and the expression for pressure drop. The removal rate of suspended solids as a function of solid concentration is written as... 

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