Solving Material Balance Problems with the Proposed Procedure

3 Solving Material Balance Problems with the Proposed Procedure 

As Einstein said, Example is not another way to teach, it is the only way to teach. Because we agree with this statement, we are fully committed to giving you a large number of examples, either solved or to be solved. In this section we will provide some warm-up examples to start practicing the proposed procedure. 

It is definitely advisable to follow these two warm-up examples step by step. They are simple but will guide you in the first steps of the proposed procedure. 

Dryer [3]. 100 kg/h of a food are fed to a continuous dryer (H2O removal) operated under steady-state conditions to reduce its moisture content from 88 to 12 %. Assume that for the purpose of the problem the food has two components solids and H2O (Fig. 7.20). (a) What is the amount of dried food obtained (kg/h) (b) How much H2O (kg/h) is removed in the continuous dryer  

It might appear to be an exaggeration to follow the proposed procedure (Fig. 7.15) for such a simple problem that an advanced student could probably solve without any strategy. Experience has repeatedly shown us that, although it is simple, it is better and advisable to always follow the proposed procedure. It is a good idea to remember our experience with the shoe problem in Chap. 5. Maybe you solved it mentally and got the wrong answer. Our purpose here is to familiarize you with the proposed procedure and demonstrate its use. 

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