AIMS AND LEARNING OUTCOMES

The module proposes itself to provide to the students the basic tools for the analysis of the transformation processes. The course deals with macroscopic balances of material and energy, devoting particular attention to applicative examples on topics characteristic of the chemical and process engineering.

The attendance and active participation in the proposed training activities (frontal lessons, exercises and computer lab) and individual study will allow the student to:

• correctly write the macroscopic balances of material and energy and discuss them using appropriate vocabulary;

• apply the macroscopic balances of material (by mass and moles) and of enthalpy to single unit operations typical of chemical engineering;

• identify possible simplifying assumptions in the framework of process problems which can be solved using material and energy macroscopic balances;

• integrate the balances solution with the knowledge of thermodynamics acquired in the first module in terms of phase and reaction equilibrium;

• calculate the diagram (flow rates, concentration, temperature) describing a process scheme with a number of unit operations;

• evaluate from a macroscopic point of view the convective and diffusive fluxes in different control volumes;

• use the main functions of the simulation software Aspen Plus for the balance solution.

PREREQUISITES

For a successful learning basic knowledge of mathematics, chemistry and physics are required, but no formal propaedeuticity is provided.

TEACHING METHODS

The presentation of theoretical contents (30 hours) are alternate by exercises (26 hours) carried out by the teacher on the board or by student teams and aimed at encouraging learning and the discussion of specific examples of process engineering applications. In addition, it is foreseen a computer lab (4 hours) with numerical exercises to be carried out in working groups using a commercial software. The frequency of lessons is recommended.

Transversal skills in terms of communication skills and independent judgment will be acquired through the teamwork, a test developed in the classroom by consulting technical handbooks and an exam test simulation.

SYLLABUS/CONTENT

The program of the module includes the presentation and discussion of the following topics: 

1. Introduction (5 hours)

         Main chemico-physical variables, vocabulary, general balance formulation

      2. Macroscopic material balance (25 hours)

         Macroscopic material balance by mass and moles (complete and simplified formulation);

         steady-state and transient conditions, in open and closed systems;

         case studies with reactions where yield, kinetics or equilibrium are supposed;

         freedom degree calculation in process plants;

         strategy for the solution of process problems;

         use of technical handbook as data sourcing;

         material transport coefficient;

         diffusive fluxes at the interface with phase equilibrium or reaction.

       3. Macroscopic balance of energy (20 hours)

         Macroscopic balance of energy and its simplification to enthalpy balance;

         steady-state and transient conditions, in open and closed systems;

         case studies with reactions and relation to material balances;

         application to process plants;

         heat transport coefficient;

         thermal resistances in series on flat and cylindrical geometry;

    4. Summary exercises (6 hours)

          Case studies requiring the solution of both material and energy balances.

      5. Computer lab (4 hours)

         Basic knowledge for the use of the simulation software Aspen Plus;

         solution with Aspen Plus of easy process problems based on macroscopic material and energy balances and related           sensitivity analyses.

RECOMMENDED READING/BIBLIOGRAPHY

The teaching material used during the lessons will be available in the web classroom, as well as examples of final tests proposed in the previous years and a trace for their solution. The notes taken during the lessons and the material in the web classroom are sufficient for the preparation of the exam, but the following books are suggested as supporting and deepening texts:

- D.M. Himmelblau amd J.B. Riggs, Basic Principles and Calculations in Chemical Engineering, Prentice Hall Pearson Edication.

- M.C. Annesini, “Fenomeni di trasporto. Fondamenti e applicazioni”, Edizioni Hoepli.

- R. Mauri, Elementi di fenomeni di trasporto, Plus Pisa University Press.

- R.H. Perry, D.W. Green,“Perry’s chemical engineers’ handbook” VIII ed., Mc Graw Hill.