IA/0188/EN - SAFETY AND ENVIRONMENTAL CHEMICAL ENGINEERING WITH DESIGN PROJECT
Academic Year 2022/2023
Free text for the University
ALESSANDRO CONCAS (Tit.)
- Teaching style
- Lingua Insegnamento
|[70/88] CHEMICAL AND BIOTECHNOLOGICAL PROCESS ENGINEERING||[88/00 - Ord. 2020] PERCORSO COMUNE||12||120|
- Knowledge and understanding: the goal of the course is to provide to the students: i) the fundamentals for the identification of hazards in the process industry and the capability to evaluate the consequences of accidents as well as to estimate the frequency of their occurrence and quantify the related risk. Furthermore, the basic skills to implement and design strategies for the risk reduction and safety increase will be provided to the students. ii) The course will also provide the tools to critically assess air pollution phenomena generated mainly by the chemical industry as well the fundamentals underlying the techniques to size and design unit processes for the removal and abatement of contaminants from the effluents.
- Ability to apply knowledge and understanding: the knowledge acquired in the course will allow the student to identify the technical choices to be made in order to implement plant and design strategies aimed to increase the reliability and safety of specific industrial processes. The acquired knowledge will also allow to implement strategies for the reduction polluting emissions from the chemical industry as well as to carry out the design of the main units involved in air pollution control systems.
- Making judgments: the student will be able to independently identify the risks and safety concerns deriving from a specific industrial process based on the relative P&ID diagram and to understand the measures and strategies to be developed in order to reduce the associated risks. The student will also be able to elaborate and critically interpret a situation of pollution produced by gaseous emissions from the chemical industry and subsequently formulate an appropriate technical choice for its resolution, taking into account the best available techniques.
- Communication skills: the student will be able to communicate using the technical English terminology.
- Learning skills: The student will be able to expand its knowledge independently by drawing from different bibliographic sources
Basic knowledge of Basic Physic and Chemistry. Basic knowledge of Reaction Kinetics, Transport phenomena, Fluid dynamics, Thermodynamics and Chemical plants.
The course consists of two main learning units:
LU1: Chemical process safety (40 hr lessons, 20 hr exercises)
Introduction with particular emphasis on security programs, ethics in engineering, concept of acceptable risk, risk matrices; inherent safety concept. Fundamentals of toxicology: toxicants exposure pathways, dose-response models, TLV concept. Industrial hygiene: compound safety data sheets, assessment of workers' exposure to toxic compounds, noise and heat, dust control systems such as ventilation and respirators. Source models: flow of liquid and vapors through a hole from tanks and pipes under adiabatic or isothermal conditions, liquids subject to flashing, pool evaporation or boiling. Quantification of toxicants’ emissions and dispersion models: environmental parameters that affect dispersion, dispersion advection equation, Gaussian puffs and plumes, specific applications to the cases of non-stationary release from point and linear sources, steady state release with and without wind, Pasquill-Gifford model, estimation of plume rise, dispersion of dense gases, criteria for the evaluation of toxic effects. Fires and explosions: fire triangle, flammability criteria of mixtures of liquids and vapors, limiting oxygen concentration and inertization, flammability diagram and ignition energy, self-ignition, explosions. Fire and explosion prevention: inertization, electrostatic ignition prevention; explosion-proof units and equipment, ventilation and sprinklers. Chemical reactivity: identification of hazards from chemical reactions and their characterization by calorimeters, theoretical interpretation of calorimeter data, control of hazardous reagents. Relief systems and valves: typologies, features and sizing. Hazard identification: overview of HAZOP methods and techniques. Risk analysis: general probability and statistical references, tree of events and failures, quantitative risk analysis and layer of protection analysis, independent protection levels.
LU1: Environmental chemical engineering (40 hr lessons, 20 hr exercises)
Definition of air pollution. Classification and general properties of air pollutants (primary and secondary). Sources of air pollutants. Air pollution measurements: enviornmental monitoring and source sampling. Emission factors. Emission inventory. Scales of the air pollution problem. Acid Rain, Greenhouse effect. Ozone layer depletion. Photochemical smog. Ocean acidification due to atmospheric CO2 absorption. Quantification of emissions from combustion processes and kinetics of NOx formation. Fundamentals of meteorology. The Gaussian model of dispersion of pollutants in the atmosphere. The evaluation of the effective height of release. Sizing of stacks. Basics of Air Pollution legislation: Emission ceilings and Air Quality Standards. Air pollution control devices. Control of particulates: gravity settlers, cyclones, electrostatic precipitators, fabric filters, particulate scrubbers. Control of gases and vapors. Adsorption, Wet scrubbing, Thermal/Catalytic combustion, Biofiltration. Control of Sulfur Oxides. Control by prevention. Fluidized bed Combustion. Fuel desulfurization. Control of Nitrogen Oxides. Control by prevention. Combustion Modification. Flue gas treatment. Control of VOCs. Adsorption and absorption columns. Biological oxidation. Catalytic combustion. Condensation. Notes on software for the design of air pollution treatment plants.
The course includes lectures (67%) and exercises (33%). The lectures will rely on power point presentations and the traditional blackboard. Videos and animations will also be shown for explanatory purposes on the operation of specific plant units. During the exercises students will be asked to test their problem solving skills by numerical solutions of problems concerning the two main topics of the course: i.e. the chemical. During the exercises, students can rely on different computer tools for solving problems ranging from programming languages to open source software to the ones for the risk analysis and the design of treatment plants. During the lessons, the teacher recalls the links to the other disciplines addressed in the degree course and stimulates the participation of students to the discussion of the topics addressed. There will be two seminars on topics concerning the safety and the environmental chemical engineering sections of the course, respectively.
Verification of learning
The exam consists of an oral aimed to verify the capacity of solving a problem related to the safety of chemical processes as well to air pollution phenomena. Sizing of the units to implement safety plans and treat air pollution will be a typical problem addressed in the oral exam. The oral exam will ascertain the knowledge and understanding of air pollution phenomena and air pollution control and the ability to analyze environmental issues by linking the different topics covered during the course. All the theoretical aspects of the topics discussed during the lectures will be also addressed during the oral exam.
Crowl, Daniel A., and Joseph F. Louvar. "Chemical Process Safety-Fundamentals with Applications, (2011)." Process Safety Progress 30.4 (2011): 408-409.
Cooper, C. David, and Forrest Christopher Alley. Air pollution control: A design approach. Waveland press, 2010.
Reynolds, Joseph, John S. Jeris, and Louis Theodore, eds. Handbook of chemical and environmental engineering calculations. John Wiley & Sons, 2007.
During the course, lecture slides and supplementary material will be supplied through the platform agreed with the students.