Probing the charge state of ambient and indoor aerosols

Lead Research Organisation: Imperial College London
Department Name: Civil & Environmental Engineering

Abstract

Electrostatic charge on aerosols plays a significant role in global air pollution, in pollution control technologies and in industrial aerosol processes. Charge can influence the behaviour of particles as they are transported around at global and micro scales. It influences how particles coagulate and can affect how likely they are to deposit within our lungs. In industrial processes the transport and generation of powders can lead to very high levels of charge being built up on particles and similar effects are observed within vacuum cleaners. In filtration processes electrostatic charge is often employed to improve efficiency of filter media by influencing both the charge on the particles and the charge on filter fibres.

Fundamental understanding of the charge state of different sources of aerosols, i.e. the distribution of charge on particles of different sizes, and the interactions between particles in ambient and indoor environments could lead to improvements in designing pollution control technologies, including filtration and separation systems. Therefore, there is a need to develop measurement tools to effectively and quickly measure the charge state of aerosols.

This PhD project aims to:
1. Develop novel measurement techniques for aerosol charge state that can be applied to a wide range of aerosol types, sizes and species.
2. Use experiments to quantify and evaluate the charge state of different aerosols that are emitted from different sources, which can be found in different indoor and ambient environments. Measure how charge states can evolve due to particle interactions.
3. Develop new modelling tools utilising Computational Fluid Dynamics that account for particle charge state, recombination and charge decay effects that occur with different aerosols in different environments. The model outputs will be compared to the earlier experimental work to understand the physical phenomena that affect charge state that could go on to inform the design of air cleaning devices.

Relevant EPSRC research areas: Analytical science, Particle technology, Sensors and instrumentation

Publications

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Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/S023593/1 01/04/2019 30/09/2027
2274780 Studentship EP/S023593/1 01/10/2019 30/09/2023 Peter Knapp