Project title:
Reduction of nanoparticle emissions by the optimization of residual combustion gases filtering processes
No. 175/25.10.2011
This work was supported by a grant of the Romanian National Authority for Scientific Research, CNCS – UEFISCDI, project number PN-II-ID-PCE-2011-3-0762. style=”color:”
Goal of the project is to reach effective ways to manipulate nanoparticle suspensions in fluid media using dielectrophoresis, in order to their retaining from flue gas and improving the filtration precesses. Nanoparticles are a major polluting factor, with impact on the environment and health. Massively generated in combustion processes they are highly toxic: once inhaled, penetrate, enter the blood, and can reach the brain, with irremediable damages. Therefore, combustion gases filtering become a major objective. The classical methods (mechanical, optical) provided poor results, o promising direction of research being dielectrophoresis (DEP): the movement of polarizable matter placed in a non-uniform electric field. The DEP force depends on the particles physical properties (size, electrical properties), fluidic medium, and of the applied field. By using DEP can manipulate nanoparticles suspended in fluidic media (air filtration, water purification) or to separate cancer cells from blood, bacteria, and viruses. The project intends to study the nanoparticles electrohydrodynamic: the movement in a fluid medium under the DEP, viscosity, gravitational forces, etc. The numerical simulations will provide the knowledge necessary for a device designed to nanoparticles manipulation and some experimental research regarding the filtering of combustion gases evacuated from a waste incinerator will do. Substantiation of a model of public environmental policy and strategies meant to reduce nanoparticles emissions in the city of Timişoara will do finally.1. Project Objectives
Main objective: To reduce nanoparticles pollution in the environment.
The general interdisciplinary objectives of the project are:
– Mathematical modelling and numerical simulation of the behaviour of nanometric particle suspensions in fluid compressible environment – combustion gases – under the action of an electric field for describing nanoparticles capture,
– Experimental modelling and optimization of filtering processes, in order to reduce the nanoparticles emissions in the combustion gases,
– Development of a pre-feasibility study of the suggested product both from an economic perspective and in terms of an intervention through public policy, in order to estimate the intention of investing in nanometric particle filters.
Operational objectives and estimated results:
O1: The build-up of a data basis containing the main theoretical and experimental results published in the field
Documentation and classification of the bibliography based on specific criteria: theoretical, computational, experimental, nanoparticles analysis and characterization
O2: Mathematical modelling of the behaviour of nanometric particle suspensions in compressible fluid under the action of an electric no uniform field
2.1 Identification of the system of equations which governs the system dynamics, the computational domain, the specific initial and boundary conditions
All forces acting upon the suspension particles (viscous resistance force, gravitational force, Archimedes force, Brownian force, Van der Waals force) will be identified and the equations that govern the particle movement under these forces will be written. The movement equations will be solved in a suitable computational domain, under specific boundary and initial conditions.
2.2 Determining the values of the parameters involved in the system
For a realistic description of the system, the numerical values of the material or geometric parameters involved in the equation system must be known. Their value will be determined using data taken from literature.
O3: Numerical implementation of the mathematical model
3.1 Developing the programme for simulating the nanoparticles dynamics in AC electric fields
The movement equations will be solved in a suitable computational domain, by introducing the value of the material parameters as well as the specific boundary and initial conditions. The numerical calculations will be performed with ANSYS Multiphysics, competitive specialized software using the finite element method.
3.2 Validating the developed programme by comparing the obtained results to the results published in the specific literature
The programme will be validated by comparing it to results published in the literature on geometry or problems that are less complex than the studied one. The number of nodes in the computational domain and the time step required for numerically correct solutions will be determined. Following this stage, the more complex problem studied as part of this project can be solved.
O4: Numerical simulation of the behaviour of nanoparticles suspensions in combustion gases, under the action of an electric field for particle capture
The great advantage of using numerical simulations in describing complex systems is that they allow the testing of the behaviour after a large number of parameters have been changed; the testing procedure is performed at low costs and in a relatively short time.
4.1 Studying the influence of particle characteristics and fluid environment
The dimension of the suspension particles is a parameter that has a major influence on the forces that act in the system. Based on the numerical simulations, one can determine the trajectories of the particles of different sizes under the action of the electric field applied with various electrodes. In addition, by changing some programme parameters, numerical simulations allow the investigation of the role played by the physical properties of the particles, combustion gases temperature and velocity.
4.2 Determining the system parameters to develop an optimal nanoparticles capturing process
Starting from the studies mentioned at 4.1 and based on a systematic analysis, one can determine the set of geometrical (electrode shape and place, particle size) and physical-chemical parameters that lead to an optimal nanoparticles capture process.
O5: Experimental modelling of nanoparticles capture process within the combustion gases emissions in a non-uniform electric field based on simulations results.
5.1 Designing, building and testing an experimental device for capturing particles from the combustion gases in an electric field
Based on the results obtained during the simulations specified at O4, in co-operation with ProAirClean, a waste incineration company in Timişoara, we will design, building and testing an experimental filter for capturing of nanometric from the combustion gases particles in a non-uniform alternating electric field.
5.2 The collecting of the nanometric particles
By using the experimental device, the nanometric particles exhausted by incinerator of ProAirClean Timisoara will be retained and separately collected.
O6: The analysis of the collected nanometric particles
The particles collected with the experimental device will be analyzed and characterized. The study will be focused on quantities, size classes and composition. A comparison of the obtained results with data from literature will be performed.
O7: Establishing of efficient regimes in nanoparticles manipulations using the “Design of experiments” method.
A feedback will be created that will lead to improved mathematical methods, best possible experimental methods and optimal parameters of nanoparticles capture processes.
7.1 The improvement of the mathematical model
7.2 The optimization of the experimental device geometry
7.3 The optimization of the physical and chemical parameters of the separation process (the voltage applied on the electrodes, the frequency, the fluid medium characteristics).
O8: Substantiation of a model of public environmental policy and strategies meant to reduce nanoparticles emissions in the city of Timisoara. The identification of the utility domains and of the potential users
8.1 Estimating the range of nanoparticles emissions in Timisoara
The economic agents whose production processes generate nanoparticles emissions will be identified. A map of the nanoparticles pollution in Timişoara will be drawn with the help of systematic measurements of the nanoparticles air level in key points.
8.2 Proposing an intervention model for the reduction of nanoparticles emissions in Timisoara
Examples of successful intervention policies in the European Union member states will be studied. Based on them, a paper describing the desirable situation will be drawn up. Round tables with the local decision-making authorities will be organized to inform them about the results of the project and to know their position regarding the nanoparticles emissions issue. Workshops will be organized and visits will take place to economic agents generating polluting emissions, in order to estimate their intention to invest in nanometric particle filters.
Works plan for project implementation
Year | Objectives | Associated activities | Deliverables | Implementation |
2011 | The build-up of a data basis containing the main theoretical and experimental results published in the domain. | Documentation and classification of the bibliographic material on specific domains : theoretical, computational, experimental, analysis and characterization of nanoparticles | Classification report. Scientific stage report. | Done |
2012 | The build-up of a mathematical model for describing the studied system (suspensions of nanometric particles in a fluid medium, subject to an electric field)
| The founding the system of equations which governs the system dynamics, the computational domain, the specific initial and boundary conditions | Equations system. | Done |
The physical and chemical analysis of the system. | Parameters report. | Done | ||
The establishment of the parameter values appearing in the system |
| Done | ||
The numerical implementation of the mathematical model | The build-up of the program for the simulation of nanoparticles dynamics in electric field The validation of the program by comparisons with previously published results | Simulation program. | Done | |
Numerical study on the mobility and dispersion rate of the nanoparticles in fluid medium subject to electric field in order to control their retention or separation | Numerical study. Scientific stage report. | Done | ||
2013 | Numerical simulation of the behavior of suspensions of nanoparticles in the flue gas under the action of electric field, in order to retain them.
| The study of the influence of the physical properties of the particles and fluid
| Determining the trajectories of particles with different sizes and concentration fields under the action of electric field applied using electrodes of different forms, depending on the nature of the particles and fluid medium, at different frequencies. | Done |
Finding the parameters of the system for an optimal trapping of the nanoparticles
| Identification the set of physical and chemical parameters of the system (shape and location of electrodes, particle size, frequency of the applied voltage, material characteristics of substances used) that lead to optimization of particle trapping. | Done | ||
Experimental researches and modeling on manipulation of nanoparticles in flue gas fluid suspensions subject to non uniform electric fields (dielectrophoresis), based on simulations results.
| Chemical and size classes analysis of the particles, exhausted by incinerator of ProAirClean Timisoara, especially using LM10 Nanosight microscope, acquired in the 2012 project phase. Comparison of the obtained results with data from literature. | Create a catalog of particles emitted over a period of 6 months, correlated with the type of waste incinerated. | Done | |
The design and build-up of an experimental device for retaining the nanoparticles from combustion gases in non uniform electric fields. | Experimental device. Scientific stage report. | Done | ||
2014 | Performing experiments on nanoparticle trapping from flue gases resulting from waste incinerator Pro Air Clean Timisoara, by using the experimental device.
| Analysis and characterization of collected particles (the study of granulometric class particles and determination of their nature and resulted quantities).
| Analysis report. | Done |
Establishing of efficient regimes in nanoparticles manipulations using the “Design of experiments” method. The optimization of the physical and chemical parameters of the separation process (the voltage applied on the electrodes, the frequency, the fluid medium characteristics). The optimization of the experimental device geometry. | Feed-back on the improvement of the mathematical model and experimental device. | Done | ||
2015 | Substantiation of a model of public environmental policy and strategies meant to reduce nanoparticles emissions in the city of Timisoara.
| Estimating the scale of the phenomenon of emission of nanoparticles in the city of Timisoara. Identification of economic agents, whose production processes leads to emission of nano-particles. | Map of nano-particle pollution for city of Timisoara. | Done |
2016 | The identification of the utility domains and of the potential users | Based on examples of good practice in the area of intervention policies in EU countries, will propose a model intervention to limit the emission of nano-metric particles in the city of Timisoara. Visits in industrial units possibly interested in the project (metallurgy, water cleaning stations). Round tables, workshops. | Study on good practices in policies of intervention in European Union countries.
| Done |
Intervention model to limit the emission of nanoparticles in Timisoara city. Estimating concerning the endowment intent with nanoparticle filters. | Done |
- Particulate matter dispersion in Timisoara urban area.pdf
- Study on nanoperticle flow reduction tests to HWI plants.pdf
- Air quality monitoring and policies of intervention in EU countries
- Work visit, round tables
- Intervention model to limit the emission of nanoparticles in Timisoara city
- Scientific report 2016
