Heterogeneous reaction engineering

Presentation

Program (detailed contents):

- Interest and technologies for heterogeneous reactors.

- Catalytic reactors: Notions of catalyst and heterogeneous kinetics; Limitations by external or internal mass transfer, Calculation of effectiveness factors, Thiele Modulus, Modelling and design of fixed bed reactors (mass balances).

- Gas/liquid reactors: Gas/liquid mass transfer with chemical reactions; Hatta Number; Enhancement factor, Working regimes; Modelling and design of gas/liquid reactors; Choice of the reactor type.

- Biological reactions and reactors: analysis of stoechiometry and kinetics of biological reactions; Bioreactor analysis:  design and operation of batch, fed-batch and continuous bioreactors, with or without recycling based on simple reaction kinetics with the goal of cell or metabolite production and pollution treatment

Organisation:

Lectures, tutorials, labwork.

Cases study project in small groups: definition of the physical problem and writing of the equations for a complex system including the transport and heterogeneous reaction steps and its resolution using a numeric tool.

Objectives

At the end of this module, the student will have understood and be able to explain (main concepts):

- the different types of chemical and biological catalysts and their working modes

- the stoichiometry, kinetic laws and their combination for the description of microbial cell behaviour for growth and production,

- the notion of limiting step(s) in heterogeneous reactions

- the notion of apparent reaction rate

- the expression and meaning of dimensionless numbers (Hatta, Thiele, Weiss, Biot...)

- the notions of effectiveness factor and enhancement factor

- the description and modelling of batch, fed-batch and continuous, single or multi stage biological reactors with or without recycling.

The student will be able to:

- determine the limiting process(es) in a chemical heterogeneous reaction

- express the apparent global rate of a chemical reaction depending on the working conditions

- identify the general metabolic scheme of microbial growth

- establish the stoichiometric equations and kinetic laws for biological reactions with respect to the environment conditions

establish an intrinsic kinetic law

- select and design the most suitable reactor to perform a given reaction

- integrate and prioritize the mechanisms in order to model homogenous and heterogeneous biological and chemical reactors

Needed prerequisite

Transport and reaction in fluid media

Fluid properties and mass transfer

Thermodynamics

Thermal transfers and reactors

Microbiology and statistics

Form of assessment

The evaluation of outcome prior learning is made as a continuous training during the semester. According ot the teaching, the assessment will be different: as a written exam, an oral exam, a record, a written report, peers review...