The proposed research is to address the EPA new air quality standards by developing a new generation of more efficient and low cost electrostatic precipitators (ESPs) for which a permanent U.S. patent is pending. This is a novel concept based on the replacement of the particle collection plates in all ESPs by membranes made from inexpensive advanced materials. Instead of conventional rapping, in which heavy plates are pushed (buckled) to dislodge collected dust, the membranes will be either pulled to induce shear for dislodging the collected particles or cleaned by other novel means. This should result in decreased re-entrainment of particles and reduced complexity of the ESP.

Approach:

The preliminary experiments conducted at Ohio University with different membrane materials in a small-scale ESP show that membranes woven from carbon fibers can be used to collect dust particles as efficiently as conventional steel plates. However, ESPs operating in more severe thermal environment would require the use of a ceramic fabric, which must be coated to provide the electrical conductivity. The success of this concept depends on two key issues that will be studied in detail. The first is the induced vibration in the membranes. Relationship between the dust collection/removal efficiencies and vibration parameters such as gas flow speed, membrane tension, etc., need to be better understood. There are strong indications that the membrane vibration can be controlled by a proper design and by adjusting its tension. Another key factor is development of a coated membrane by integration of the required properties such as corrosion and fatigue resistance, electrical conductivity, fabric weave density etc.

Expected Results:

A significant advantage of this design is the drastic reduction in weight of collector plates, about one order of magnitude. The resulting reduction in cost of production, installation, transportation and repair of the collection surfaces should also have a significant economic effect. Another advantage of the new ESPs is that they can be fabricated from corrosion- resistant materials. Such fabrics will be suitable for implementation of new technologies for controlling gaseous, providing the next generation of ESPs with vast new capabilities to control pollution. It is also anticipated that the membrane can be coated with catalytic materials to promote removal of gaseous pollutants and heavy metals. The proposed research has elements of risk since the substitution of plates by membranes is a new concept that has not been fully tested yet.

Supplemental Key Words: particulate, chemicals, pollution prevention, innovative technology, modeling