Cane Sugar Refining - Purolite

Glossary (continued)
Cane Sugar Refining with Ion Exchange Resins
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DISSOCIATE: The process of ionization of an
electrolyte or a salt upon being dissolved
in water, forming ions of cation and anion.
DOWNFLOW: Conventional direction of
solutions to be processed in ion exchange
column operation, i.e., in at the top,
out at the bottom of the column.
DRY SOLIDS: The matter, usually expressed
in weight percent, remaining after liquid
removal.
EFFICIENCY: The effectiveness of the
operational performance of an ion
exchanger. Efficiency in the adsorption
of ions is expressed as the quantity of
regenerant required to effect the removal
of a specified unit weight of adsorbed
material, e.g., pounds of acid per kilograin
of salt removed.
EFFLUENT: The solution which emerges from
an ion exchange column.
ELECTROLYTE: A chemical compound which
dissociates or ionizes in water to produce
a solution which will conduct an electric
current; an acid, base or salt.
ELUTION: The stripping of adsorbed ions
from an ion exchange material by the
use of solutions containing other ions in
relatively high concentrations.
EQUILIBRIUM REACTIONS: The interaction
of ionizable compounds in which the
products obtained tend to revert to
the substances from which they were
formed until a balance is reached in
which both reactants and products are
present in definite ratios.
EQUIVALENT WEIGHT: The molecular weight of
any element or radical expressed as grams,
pounds, etc., divided by the valence.
EXCHANGE SITES: The reactive groups on an
ion exchange resin.
EXCHANGE VELOCITY: The rate with which one
ion is displaced from an exchanger in favor
of another.
EXHAUSTION: The state in which the resin is
no longer capable of useful ion exchange;
the depletion of the exchanger’s supply of
available ions. The exhaustion point is
determined arbitrarily in terms of: (a)
a value in parts per million of ions in
the effluent solution; (b) the reduction in
quality of the effluent water determined
by a conductivity bridge which measures
the electrical resistance of the water.
FMA: The free mineral acidity, or sum of
the mineral acids.
FINES: Extremely small particles of ion
exchange materials.
FLOW RATE: The volume of solution passing
through a given quantity of resin within a
given time. Usually expressed in terms of
gallons per minute per cubic foot of resin,
as milliliters per minute per milliliter of
resin, or as gallons per square foot of resin
per minute.
FREEBOARD: The space provided above
the resin bed in an ion exchange column
to allow for expansion of the bed during
backwashing.
GRAIN: A unit of weight; 0.0648 grams.
GRAINS PER GALLON: An expression of
concentration of material in solution,
generally in terms of calcium carbonate.
One grain (as calcium carbonate) per gallon
is equivalent to 17.1 parts per million.