Encyclopedia of Environmental Science and Engineering, Volume I and II

294 ELECTROSTATIC PRECIPITATION

The fabric filter has the following advantages for

Ravenswood Unit 3:

1) Gas distribution is not as critical as in the precipi-

tator.

2) The fabric filter can be compartmentalized to

allow for maintenance while the fabric filter is

onstream. This design allows for high availability

to the power boiler.

The fabric filter has the following disadvantages for

Ravenswood Unit 3:

1) Replacement of the existing precipitator with a

baghouse will cost $120 million (1991) but will

not improve the collection efficiency of the par-

ticular control system beyond that resulting from

the proposed precipitator upgrading.

2) Fuel switching may cause permanent fabric

blinding because of the sticky characteristics of

oil ash.

3) New induced draft fans will be required because

of a higher system pressure drop.

4) The furnaces were not designed for baghouses;

therefore, the pressure drops that occur during a

malfunction of the forced draft fans may exceed

design limits.

5) Relatively limited field experience is available

on fabric filter use on large units burning eastern

coal.

6) Higher maintenance will be required than for

electrostatic precipitators.

7) The maximum fabric filter operating temperature

is approximately 500°F; therefore, complicated

duct work would be required in order to install the

baghouse downstream of the air preheater, which

would require more plant site area.

REFERENCES

1. Ramsdell, R.G. Jr. (1961) Prediction of Fly Ash Precipitation A.I.E.E.
   Paper CP 61–399.


2. White, Harry J., (1963) Industrial Electrostatic Precipitation, Addison-
   Wesley Publishing Co.


3. Ramsdell, R.G. Jr., Design Criteria for Precipitators for Modern
   Central Station Power Plant, paper presented at American Power
   Conference April 23–25, 1968.


4. Ramsdell, R.G. Jr. and C.F. Soutar, Anti-Pollution Program of Consoli-
   dated Edison Company of New York, paper presented at ASCE Con-
   ference Environmental Engineering, Chattanooga, Tenn. May 13–17,
   1968.


5. Consolidated Edison Company of New York, October 1981. Environ-
   mental impact statement—Ravenswood Generation Station Unit 3,
   Reconversion from Oil to Coal.


6. Orange and Rockland Utilities, Inc., May 1981, Environmental impact
   statement—Lovett Generating Station Units 4 and 5, Reconversion
   from Oil to Coal.


7. Altman, R., March 1989, Improving Electrostatic Precipitator Perfor-
   mance, EPRI Jnl., p. 42.


8. Grieco, G., April 1988, Proper ESP Evaluation Demands Extensive
   Computer Modelling, Power, p. 73.


9. Han, H.P. and E.N. Ziegler, The Performance of High Efficiency Elec-
   trostatic Precipitators, Envir. Progress 3, 201 (1984).


10. Harrison, W.A. et al., Medium Sulfur Coal and Fly Ash Resistivity, Jnl.
    Air Poll. Contr. Assoc., 38, 209 (1988).


11. Daub, Kare, Low cost improvement of existing electrostatic precipita-
    tors, Power Tech. International, Spring 1996, pp. 37–40.


12. Grieco, G.J. and C. Wedig, Controlling heavy metals with electrostatic
    precipitators, Power Tech. International, Spring 1996, p. 18.

ROGER G. RAMSDELL, Jr.

Consolidated Edison Company, Inc.

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