Environmental Engineering FOURTH EDITION

List of Symbols 463

WPDES
W

W
Wi

W

x21 Y2

X1
x2
XO
X

Y
Y
Y

Y

YF
Y

Z

Z(t)

Z

Wisconsin Pollutant Discharge Elimination System

power level, watts

cake deposited per volume of filtrate, kg/m3

specific energy, kWton

Bond work index, kWton

seeded dilution water in sample bottle, mL

weight fraction of particles retained between two sieves

effluent SS, mgL

influent SS, kgh

microorganism concentration, estimated as SS, mgL

effluent microorganism concentration, estimated as SS, mgL

return sludge microorganism concentration, estimated

as SS, mgk

influent microorganism concentration, estimated as SS, mg/L

particle size, m

characteristic particle size, m

mass per time of feed to a materials separation device

mass per time of components x and y exiting from a materials

separation device through exit stream 1

mass per time of components x and y exiting from a materials

separation device through exit stream 2

mass of pollutant that could have been captured, kg

mass of pollutant that escaped capture, kg

mass of pollutant collected, kg

thickness, in m

yield, AWAS

yield, kg SS producedkg BOD used

cumulative fraction of particles (by weight) less than some

specific size

volume of BOD bottle, mL

filter yield, kg/m2-s

oxygen used (or BOD) at time t, in mg/L (Chap. 4)

elevation, m or ft

depth of sludge in a bowl, m

oxygen required for decomposition, in mgL (Chap. 4)

sigma factor

alpha radiation

beta factor

beta radiation

gamma radiation

kinematic viscosity, cm2/s (Chap. 5)