00501 - Introduction to Unit Operations in the Chemical Industry

Course Unit Page


This teaching activity contributes to the achievement of the Sustainable Development Goals of the UN 2030 Agenda.

Affordable and clean energy Industry, innovation and infrastructure Responsible consumption and production

Academic Year 2022/2023

Learning outcomes

The purpose of this course is to present and discuss elementary tools for the understanding of the performance of equipment and plants in the chemical and process industry. The first goal is to provide the students with basic tools for the study of selected apparatus and operations and for making quantitative previsions about the performance of separation processes and chemical reactors; an additional goal is to discuss the main features of typical equipment of the chemical industry.

Course contents

- Algebraic, trigonometric, exponential, logarithmic functions. Fundamentals of calculus. Linear differential equations. Integrals in one real variable (Mathematics).
- Physical quantities and relationships that bind them, main units of measure. (Physics).
- Chemical reactions and their balance. Interpretation of pressure and temperature of a gas- Mixtures of gases and Dalton law of partial pressures (General and Inorganic Chemistry).
- Basic thermodynamic applications to chemical processes. Definition of thermodynamic system (open, closed, isolated, adiabatic). First law of thermodynamics. Equation of state of an ideal gas. Mixtures of ideal gas and Dalton's law (Physical Chemistry).

Material and energy balances for chemical equipment and plants.

Models for equipment for the chemical and process industry: equilibrium stage, degrees of freedom, design and rating problems; simple flow models (perfect mixing and plug flow).

Fluid flow: regimes for the flow in tubes and pipes, Bernoulli's equation, pressure drops, pumps, elements of external flow (Stokes' and Newton's law) and flow in porous media.

Interphase mass transfer: phase and overall mass transfer coefficients; mean logarithmic composition difference.

Heat transfer: conduction, convection, overall transfer coefficients, mean logarithmic temperature difference, heat exchangers.

Chemical reactors: main types; isothermal ideal reactors (batch, CSTR, PFR) and performance comparison; design criteria and rating problems; yield and selectivity problems.

Separation Processes: principles, working characteristics, design elements and rating problems relative to the following unit operations: absorption and stripping (in staged and packed columns); flash distillation; evaporation; adsorption; others (humidification operations; drying).

Main features of selected equipment: plate columns; packed towers; gas-solids mechanical separations (gravity settlers, impingement separators, cyclone separators, cloth collectors, scrubbers).


  • R.M. Felder, R.W. Rousseau, Elementary Principles of Chemical Processes, 3^ ed., Wiley, 2000.
  • W.L. McCabe, J.C. Smith, P. Harriott, Unit Operations of Chemical Engineering, 5^ ed., McGraw-Hill, 1993.


[Though warmly recommended to the students for widening their knowledge of the various topics, these books are not formally adopted as textbooks nor followed in a detailed way].

Teaching methods

The lessons on the above-mentioned topics and solution of exercises are given in class in the standard format, according to the official timetable. During the exercises the students do their own exercises in class either individually or in small groups under the supervision of the instructor. This is meant as a means to help the students to gradually acquire the skills to solve simple calculations as well as to improve their knowledge of the matter also in view of the final examination.

Assessment methods

The aim of the final examination is to evaluate the achievement of the main goals of the course, specifically:

- the capability to adopt suitable analysis and calculation techniques, which are presented during the course, in order to understand the working principles of the equipment and the basis design rules, in addition to the understanding of the chemical and physical phenomena occurring in equipment and processes of the chemical industry;

- the capability to use the outcomes obtained by the above analysis to improve the performances of equipment and processes of the chemical industry.

The final assessment will be via a written exam of 3 hours and an oral part. During the written assessment, the use of books, drawings, plots, tables, memoranda and text of exercises is allowed. The goal of this assessment is to check if the student is able to solve exercises on various topics of the course. The score is given in thirtieths. The goal of the oral part is to ascertain the full understanding of both the basic principles and the design rules of equipment and processes considered during the course. The score of the oral part is given in thirtieths. The global score takes into account the results obtained both in the written and in the oral assessments, relative weight on the final score: about 1/3 e 2/3, respectively.

Teaching tools

Syllabus, drawings, plots, tables and text of exercises: distributed in class during the course.

Office hours

See the website of Alessandro Paglianti

See the website of Giuseppina Montante

See the website of Francesco Maluta