LaMotte COD3 Plus, Руководство оператора

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COD3 Plus Colorimeter 10.16
Silica
, Low Range
SILICA – LOW RANGE
HETEROPOLY BLUE METHOD • CODE 3664-SC
QUANTITY CONTENTS CODE
30 mL *Silica Reagent #1 *V-4466-G
30 mL *Silica Reagent #2 *V-4467-G
30 mL *Silica Reagent #3 *V-4468-G
10 g Silica Reagent #4 V-6284-D
1 Spoon, 0.1 g, plastic 0699
*WARNING: Reagents marked with an * are considered to be potential health hazards.
To view or print a Safety Data Sheet (SDS) for these reagents go to www.lamotte.com.
Search for the four digit reagent code number listed on the reagent label, in the
contents list or in the test procedures. Omit any letter that follows or precedes the four
digit code number. For example, if the code is 4450WT-H, search 4450. To obtain a
printed copy, contact LaMotte by email, phone or fax.
Emergency information for all LaMotte reagents is available from Chem-Tel:
(US, 1-800-255-3924) (International, call collect, 813-248-0585).
Silicon dioxide, SiO
2
, commonly known as silica, occurs in all natural water. Silica may be
present as suspended, insoluble particles in a colloidal or polymeric state. It may also
be present in a reactive form as silicic acid or silicate ions. Silica is a major nutrient for
diatoms. A silica cycle occurs in many bodies of water containing organisms, such as
diatoms, that use silica in their skeletal structure. The silica removed from the water
may be slowly returned to solution by the decomposition of the dead organisms. The
major source of silica in natural water is from the decomposition of silicate minerals in
the drainage basin from which the waters fl ow.
The presence of silica is particularly objectionable in water used for boiler feed water
purposes, as it may cause the formation of a hard, dense scale which has unusually
high resistance to heat transfer. Serious loss of turbine effi
ciency results from insoluble
silica turbine blade deposits caused by vaporization of silica from boiler water.
Testing