Glossary Of Water Treatment
Industry Terms . . . "I"
indicator-
A material which can be used to show the endpoint of a chemical reaction,
usually by a color change, or a chemical concentration by a depth or shade
of color. influent-
The stream entering a unit, stream or process, such as the hard water
entering an ion exchange water softener. inorganic matter -
Matter which is not derived from living organisms and contains no organically
produced carbon; includes rocks, minerals and metals. installation-
The process in which water conditioning equipment is connected into the
water system, and a drain line provided where necessary. The term is also
used to refer to the complete assembly of piping, valves, drain line,
water conditioning unit and related equipment. intermittent flow
- The term usually applied to the interrupted patterns of water usage;
also used in reference to specific on-off flow patterns selected to test
the performance of water conditioning equipment under standard conditions,
which may or may not be similar to actual patterns of use of installed
equipment. ion - An atom or group of atoms
which function as a unit, and have a positive (cation) or negative (anion)
electrical charge, due to the gain or loss of one or more electrons. (See
ionization.) ion exchange- A
reversible process in which ions are released from an insoluble permanent
material in exchange for other ions in a surrounding solution; the direction
of the exchange depends upon the affinities of the ion exchanger for the
ions present, and the concentrations of the ions in the solution. (See
base exchange.) ion exchanger -
A permanent, insoluble material which contains ions that will exchange
reversibly with other ions in a surrounding solution. Both cation and
anion exchangers are used in water conditioning. (See anion, cation, ion.) ionization - The
process in which atoms gain or lose electrons; sometimes used as synonymous
with dissociation, the separation of molecules into charged ions in solution. ionization constant
- A constant specific for each partially ionizable chemical compound
to express the ratio of the concentration of ions from the compound to
the concentration of un-ionized compound. iron - An element often
found in ground water. It is objectionable in water supplies because of
the staining caused after oxidation (bleach) and precipitation, tastes,
and unsightly colors produced when iron reacts with tannin in beverages
such as coffee and tea. iron bacteria-
Microorganisms which are capable of utilizing ferrous iron, either from
the water or from steel pipe, in their metabolism, and precipating ferric
hydroxide in the sheaths and gelatinous deposits. These organisms tend
to collect in pipe lines and tanks during periods of low flow, and to
break loose in slugs of turbid water to create staining, taste and odor
problems. (See Crenothrix polyspora, Gallionella ferruginea.) |