Circulating cooling water system for supplementary water quality requirements and the index? [Jun 26,2014]
1) said the water scaling matter content index - hardness (H)
The water calcium magnesium salts of total content called the hardness of water. Hardness is divided into carbonate hardness and the carbonate hardness, namely
Total hardness = carbonate hardness + not carbonate hardness
Carbonate hardness refers to calcium and magnesium carbonate and bicarbonate (bicarbonate) the sum of content, but as a result of carbonate in the water solubility is small, so will be carbonate hardness as water calcium, magnesium bicarbonate content, saying it for temporary hardness. Because calcium, magnesium bicarbonate in heating is not stable, easy to decompose into carbonate and adhere to the heat exchanger pipe wall, become a scale. The carbonate hardness is calcium, magnesium chloride, the content of sulphate, etc. Long time after boiling also cannot remove hardness called permanent hardness.
In addition, a measure of the hardness of the unit and the German degrees (OG), each premium contains equivalent to 10 mg CaO calcium magnesium ion called OG 1. Additional, usable still each premium contained in the CaC03 of mg number to represent. Between them, the conversion relations for
LMG equivalent/L = 2.8 OG = 50 mg/L CaC03
(2) said the water alkaline substance content index - alkalinity (A)
The water OH -, CO2-3, HCO - 3 plasma and other weak acid salts of total content called alkalinity. Natural water, weak base salt mainly bicarbonate, alkalinity is mainly composed of HCO - 3 formation, therefore, natural water alkalinity general and the size of the temporary hardness is similar. Said alkalinity unit and hardness is same, for mg equivalent/L.
If water alkalinity is greater than the hardness (A > H), it is shown that the water had not the carbonate hardness, known as the alkaline water.
When the hardness is greater than the alkalinity (H > A), indicates that water china-africa carbonate hardness (permanent hardness) proportion are higher, known as the alkaline water.
(3) said the water organic content index - water oxygen consumption
Use of organic matter of oxidizability, water oxygen consumption measurement. Water oxygen consumption defined as oxidation each premium contain organic matter need oxygen consumption, the quality of the unit is mg/L.