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Шкала измерительного прибора, взвешенные частицы, реактив,
компаратор цвета, луч света, немедленный результат, по капле, поверх-
ностные источники водоснабжения, мутность, оседающие ( в течение 1
ч ) взвешенные твёрдые частицы, конечная точка, рассеивать свет, сис-
темы очистки воды, определение осаждаемости, отстаиваться, доза
флокулянта (хлопьеобразующего агента), объем грязи
19. Read about water testing methods and say which of them you use or
have ever used.
WATER TESTING METHODS
Colorimetric Method
This is defined as the measurement of a parameter when the concentra-
tion is directly proportional to color development and intensity after the addi-
tion of known volume of
reagent chemicals.
To determine concentration, the color developed in the sample is either
compared visually with manufacturer supplied standards (color comparator)
or inserted into a photometer, colorimeter, or spectrophotometer to give re-
sults directly on a meter scale, or digitally via a discrete readout. Results are
expressed as parts per million (ppm), milligrams per liter (mg/L), grains per
gallon (gpg), etc.
Colorimetric methods using a photometer, colorimeter, or spectropho-
tometer offer a unique advantage. Many meters are battery powered and con-
veniently packaged for portability. To briefly describe their operation: a light
beam is pointed at a sample. Depending upon the amount of color present,
light will pass through the sample and be detected by a photodiode. With the
aid of electronics, the results are displayed on a meter, either directly in con-
centration or as a percentage of light transmitted. Colorimetric test methods
offer on-the-spot results and can test for a variety of common substances.
Tests for chlorine, iron, manganese, copper, zinc, aluminum fluoride, ozone,
nitrates, phosphates, sulfides, and many more materials are available.
Titrimetric Method
In this procedure a sample is taken, and reagent known as an indicator
reagent is added to produce a color. A “titrant” or a reacting reagent is added
drop by drop until a color change occurs. The point at which the color
changes is called the endpoint. Titrimetric methods offer a number of titrant
dispensing apparatuses: Titration methods are generally quite inexpensive,
and are the preferred method in many procedures. Tests for acidity, alkalin-
ity, carbon dioxide, hardness, dissolved oxygen, and chlorine are among the
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