Electrostatic Precipitators ESPs

The TSS has less potential for maximum emission control as the WGS and electrostatic precipitator (ESP). While all three technologies were designed to meet NSPS/ MACT, only the WGS and ESP can meet more stringent requirements. TSS performance can typically achieve d50 grade efficiency down to 2 microns. Most reported performance values result in emissions of 0.4-0.8 Ib/Mlb coke. Future PM2 5 regulations are a concern for TSS applications. By definition, TSS units cannot effectively remove small particles due to the cyclonic operation. 

A design consideration for an environmental application of TSS technology is location. In a PRT unit, the TSS is always located in a hot flue gas position. However, a cold flue gas position could be used for environmental applications. Depending upon the pressure control scheme, the TSS can also be located at high pressure before the flue gas slide valve and orifice chamber. This offers significant cost savings, lower material cost, and requires less plot space. On two ERA consent decree applications, this benefit was 40% lower capital cost. 

Another option to improve TSS performance is use of a sintered metal filter. This technology has typically been applied only as a fourth stage application on the TSS underflow. Pall has commercialized this barrier filter on the entire FCC flue gas on one commercial unit. 

The ESP has been used to control particulate emissions in the flue gas following an FCC regenerator since the 1940s with well over 200 FCCU applications. The 

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The potassium combines with the sulfur to form potassium sulfate, which condenses as a soHd primarily in the electrostatic precipitator (ESP) or baghouse. The recovered potassium sulfate is then deUvered to a seed regeneration unit where the ash and sulfur are removed, and the potassium, in a sulfur-free form such as formate or carbonate, is recycled to the MHD combustor. It is necessary also to remove anions such as Cf and E which reduce the electrical conductivity of the generator gas flow. These are present in the coal ash in very small and therefore relatively harmless concentrations. As the seed is recycled, however, the concentrations, particularly of CF, tend to build up and to become a serious contaminant unless removed. 

After the SO converter has stabilized, the 6—7% SO gas stream can be further diluted with dry air, I, to provide the SO reaction gas at a prescribed concentration, ca 4 vol % for LAB sulfonation and ca 2.5% for alcohol ethoxylate sulfation. The molten sulfur is accurately measured and controlled by mass flow meters. The organic feedstock is also accurately controlled by mass flow meters and a variable speed-driven gear pump. The high velocity SO reaction gas and organic feedstock are introduced into the top of the sulfonation reactor,, in cocurrent downward flow where the reaction product and gas are separated in a cyclone separator, K, then pumped to a cooler, L, and circulated back into a quench cooling reservoir at the base of the reactor, unique to Chemithon concentric reactor systems. The gas stream from the cyclone separator, M, is sent to an electrostatic precipitator (ESP), N, which removes entrained acidic organics, and then sent to the packed tower, H, where SO2 and any SO traces are adsorbed in a dilute NaOH solution and finally vented, O. Even a 99% conversion of SO2 to SO contributes ca 500 ppm SO2 to the effluent gas. 

Particulate Emissions To meet environmental regulations, AFBC boilers, and some PFBC boilers, use a back-end particulate collector, such as a baghouse or an electrostatic precipitator (ESP). Compared to PC units, the ash from FBCs has higher resistivity and is finer Decause the flue-gas path contains cyclones. Both factors result in reduced ESP collection efficiency with AFBC units, but good performance has been achieved with PFBC units, where the SO3 present in the flue gas lowers the ash resistivity. In general, however, bag-houses are the preferred collection devices for both AFBC and PFBC apphcations. 

Electrostatic precipitators (ESPs) remove particles by using an electrostatic field to attract the particles onto the electrodes. Collection efficiencies for well-designed. 

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

WET ELECTROSTATIC PRECIPITATOR (ESP) WIRE-PIPE TYPE AND OTHERS... 

There are three classes of electrostatic precipitators dry electrostatic precipitators (ESP), wet electrostatic precipitators (WEP), and ionizing wet scrubbers (IWS). 

Increase in flue gas Opacity Loss of Reaotor/Regenerator levels Increase In recovery of fines from Electrostatic Precipitator (ESP)... 

Electrostatic precipitators (ESP) and wet gas scrubbers (WGS) are widely used to remove particulates from the FCC flue gas. Both can recover over 80% of filtrable solids. An ESP (Figure 10-6) is typically installed downstream of the flue gas heat recovery (prior to atmospheric discharge) to minimize particulate concentration. If both low particulate and low SO requirements are to be met, a wet gas scrubber such as Belco s (Figure 10-7) should be considered. If SO removal... 

Hot side, high dust upstream of the air preheater (APH) and electrostatic precipitator (ESP). 

After the pyrolysis gas stream passes through a cyclone and removes entrained particles, it is quenched in a tower to condense the final oil products or CDL . The tower is designed to prevent water condensation electrostatic precipitators (ESPs) recover any remaining liquid droplets and mist from the gas leaving the tower. 

Wet Electrostatic Precipitator (ESP) Wire-Pipe Type and Others... 

A coal combustion pilot plant is used to obtain efficiency data on the collection of particulate matter by an electrostatics precipitator (ESP). The ESP performance is varied by changing the surface area of the collecting plates. Figure E2.2 shows the data collected to estimate the coefficients in a model to represent efficiency 17 as a function of the specific collection area A, measured as plate area/volumetric flow rate. 

Electrostatic fluidized-bed coating, 7 55-56 Electrostatic forces, 9 569, 570 11 800 and adsorbent selectivity, 1 584 in adsorption, 1 583 in solvent-solute interactions, 23 91-92 Electrostatic particle forces, in depth filtration theory, 11 339 Electrostatic precipitators (ESP), 11 714 13 180 23 552 26 699-706 advantages of, 26 700 applications of, 26 701-703, 705t design considerations related to,... 

A semi-industrial pilot plant has been developed in which air-borne ultrasound has been applied to the reduction of particle emissions in coal combustion fumes [62]. The installation basically consists of an acoustic agglomeration chamber with a rectangular cross-section, driven by four high-power and highly directional acoustic transducers operating at 10 and/or 20 kHz, and an electrostatic precipitator (ESP). In the experiments, a fluidised bed coal combustor was used as fume generator with fume flow rates up to about 2000 m /h, gas temperatures of about 150 °C. and mass concentrations in the range 1-5 gm. The acoustic filter reduced fine particle emissions by about 40 %. 

Figure 10. Cumulative distribution curves of dust in card room atmosphere while processing cotton with an electrostatic precipitator (ESP) in filtration line. Key curve for ESP energized O, curve for ESP not energized and A, size distribution removed by ESP.

The majority of these units have a Third Stage Separator (TSS) or electrostatic precipitator (ESP) located before the SCR catalyst bed to protect against upsets in the FCC regenerator. The catalyst can easily be designed to handle the normal dust loading (60 mg-700 mg/Nm ), which is much lower than the typical coal fired boiler (5 g-9 g/Nm ). To handle a FCC upset (>15 g/Nm ) without a PM removal device, the catalyst volume would need to increase. 

Third stage separator (TSS) Electrostatic precipitator (ESP) Wet gas scrubber (WGS)... 

Plant description. Two nearly identical 430-Mw(e), western, conventional pulverized-coal-utility boilers (referred to as plants A and D) were tested. Both units use tangentially fired burners and burn low-sulfur 200-mesh coal of heat content approximately 27 000 J/g. Both units are equipped with cold-side electrostatic precipitators (ESP) of design efficiency of 99.5% or greater, and a modern flue-gas desulfurization (FGD) system consisting of four verticle spray towers. 

Particulate emissions into the atmosphere from combustion. Depending on installed filtration and scrubbing systems, fine particles (often <45 p,m) may not be collected efficiently by electrostatic precipitators (ESP Paat Traksmaa 2002) and are deposited on foliage or the ground (Ots et al. 2000), or might be inhaled by vertebrates, including humans. 

Fig. 6. Sketch of boiler (K-3A) system at the Eesti power plant, showing locations of ash sampling. Samples from locations 10 and 11 were taken from the Balti power plant (modified from Paat Traksmaa 2002, fig. 1, p. 374). Furnace bottom (1) gas duct superheater (2), economizer (3), cyclone (4), electrostatic precipitators (ESP) prechamber (5), field I (6), field II (7), field III (8), field IV (9), flue cyclone (10) and cloth filter (11). ( " Oil Shale.)...

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