Electrostatic Fabrication

ID Norris, MM Shaker, FK Ko, AG Macdiarmid. 2000.Electrostatic fabrication of ultrafine conducting fibers polyaniline/polyethylene oxide blends. Synthetic MetoA,l 14(2).pp. 109-114. 

Figure 4.5 SEM micrograph of the electrospun fibers from a 2 wt% PAn.HCSAr and 2 wt% PEO solution dissolved In chloroform at 25 kV. (Reprinted with permission from Synthetic Metals, Electrostatic fabrication ofultrafine conducting fibers polyanlline/polyethylene oxide blends by I. D. Norris, M. M. Shaker, F. K. Ko and A. G. McDiarmid, 114, 109-114. Copyright (2000) Elsevier Ltd)...

Norris, I.D., et al. 2000. Electrostatic fabrication of ultrafine conducting fibers Polyanili-ne/polyethylene oxide blends. Synth Met 114 109. 

Norris ID, Shaker MM, Ko EK, MacDiarmid AG (2(XX)) Electrostatic fabrication of ultra-fine conducting fibers polyaniline/polyethylene oxide blends. Synth Met 114 109—114. doi 10.1016/80379-6779(00)00217-4... 

Norris, I.D., Shaker, M.M., Ko, F.K., and MacDiarmid, A.G., Electrostatic Fabrication of Ultrafine Conducting Fibers Polyaniline/Polyethylene Oxide... 

Rheology. Flow properties of latices are important during processing and in many latex appHcations such as dipped goods, paint, inks (qv), and fabric coatings. For dilute, nonionic latices, the relative latex viscosity is a power—law expansion of the particle volume fraction. The terms in the expansion account for flow around the particles and particle—particle interactions. For ionic latices, electrostatic contributions to the flow around the diffuse double layer and enhanced particle—particle interactions must be considered (92). A relative viscosity relationship for concentrated latices was first presented in 1972 (93). A review of empirical relative viscosity models is available (92). In practice, latex viscosity measurements are carried out with rotational viscometers (see Rpleologicalmeasurement). 

Similar to oil-fired plants, either low NO burners, SCR, or SNCR can be appHed for NO control at PC-fired plants. Likewise, fabric filter baghouses or electrostatic precipitators can be used to capture flyash (see Airpollution controlmethods). The collection and removal of significant levels of bottom ash, unbumed matter that drops to the bottom of the furnace, is a unique challenge associated with coal-fired faciUties. Once removed, significant levels of both bottom ash and flyash may require transport for landfilling. Some beneficial reuses of this ash have been identified, such as in the manufacture of Pordand cement. 

Soiling of Antistatic Finishes. Soiling of fabrics having a tendency for accumulation of charges has been assumed to be an electrostatic phenomenon, and therefore it follows that if static is eliininated, soiling will be reduced. However, most antistatic agents have been developed and used for reasons other than the reduction of soiling. 

The most popiilar dry scrubbing systems for incinerators have involved the spray drying of hme slurries, followed by dry coUection in electrostatic precipitators or fabric filters. Moller and Christiansen [Air Poll. Cout. Assoc. 84-9.5 (1984)] published data on early European technology. Moller et al. [U.S. Patent no. 4,889,698 (1989)] describe the newer extension of that technology to include both spray-dryer absorption and dry scrubbing with powdered, activated carbon injection. They claim greatly improved removal of mercury, dioxins, and NOx. 

Chnker coohng materials handling Particulates (dust) Local exhaust system and electrostatic precipitators or fabric filters... 

Fabric filters are limited by physical size and bag-life considerations. Some sacrifices in efficiency might be tolerated if higher air-cloth ratios could be achieved without reducing bag life (improved pulse-jet systems). Improvements in fabric filtration may also be possible by enhancing electrostatic effects that may contribute to rapid formation of a filter cake after cleaning. 

Small solid particles, present in dust and grit emissions, have very low settling velocities (Table 4.4) The collection efficiencies of simple cyclones are tlierefore, as shown in Figure 17.3, relatively low. Fabric filters, electrostatic precipitators or wet scrubbers may be required to remove particles <5 pm in size with an acceptable efficiency. Therefore the cost of pollution control inevitably increases when dealing with particle size distributions skewed towards the lower end. 

Give preference to fabric filters over wet scrubbers or wet electrostatic precipitators (ESPs) for dust control. 

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