+44 (0)1509 263171
Please use this identifier to cite or link to this item:
|Title: ||Enhancing filtration by electroacoustic methods|
|Authors: ||Tuori, Timo|
|Issue Date: ||1998|
|Publisher: ||© Timo Tuori 1998|
|Abstract: ||Fouling of filter media and physico-chemical properties of suspensions decrease
the efficiency of filtration devices in a wide range of process industries.
Environmental protection causes increasing demand to clean effluent waters to
higher standards and to recycle process waters more completely.
Conventional deliquoring processes are mainly based on a single driving force,
usually gravity, underpressure or pressure. Today, multiforce deliquoring
processes based on a combination of ultrasonic and/or other nonmechanical
forces, like an electric field, are being developed. These new technological
applications, namely electro-acoustic deliquoring techniques, will most probably
enable higher deliquoring rates and final solid contents than conventional
methods have been able to yield.
Results from an experimental study of electric and/or ultrasonic field assisted
filtrations are presented in this thesis. Both electric and ultrasonic fields can reduce
fouling of the filtration medium and have a significant influence on filtration
capacity. The extent of filtration improvement is affected mostly by particle size,
surface charge, acoustic frequency, intensity and field strengths.
Theoretical examinations of the use of electric and/or ultrasonic fields to enhance
filtration efficiency are laid out. Some aspects regarding orthokinetic interaction in
acoustic agglomeration have been considered, and energy consumptions of the
filtrations of different suspensions used in experiments were also determined.
Using electric field as a pre-treatment, biolfiber suspension filtration can be
enhanced 4-fold and energy consumption of electric field enhancing the filtration
(kWh kg1 separated water; product final dry solid content 23 % by mass) was
only about 17 % of the total energy consumption of conventional vacuum
filtration. Pre-treatment units can be connected to the filtration unit, for instance
before the filter drum. Possible pre-treatment apparatuses could be
electroflotation equipment or a pre-treatment tube technique introduced in this
|Description: ||A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.|
|Appears in Collections:||PhD Theses (Chemical Engineering)|
Files associated with this item:
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.