Water Treatment Plant Operation Volume 2 Chapter 2 - Softening

Water Treatment Plant Operation Volume 2 Chapter 2 - Softening



Terms in this set (108)



What is water hardness? measure of soap- or detergent-consuming power of water


Hardness is caused by ______ divalent, cations, precipitates, scale
metallic _______ that are capable
of reacting with soap to
perform _________ and with certain
_______ present in water to form
_____

, ____ and__are usually the only calcium, magnesium
cations that

cause hardness that are
present in significant
concentrations
Hardness is most commonly mg of calcium carbonate equivalent per liter
expressed as:
water containing calcium 60
carbonate at concentrations
below ___ mg/L is generally
considered soft
water containing calcium 60-120
carbonate at
concentrations between
____________________mg/L
is
generally considered moderately
hard
water containing calcium 120-180
carbonate at
concentrations between
____________________mg/L
is
generally considered hard
water containing calcium 180
carbonate at concentrations
above ___ mg/L is generally
considered very hard
Hard water is water high, calcium, magnesium
having a ____
concentration of ____
and
____________________
ions
Calcium hardness is caused by calcium ions
magnesium hardness is caused by magnesium ions