The salt put in the water in the boiler is mainly phosphate,
1, increase the boiling point, play the role of sterilization. After adding salt boiling point can be increased to about 104 degrees, the water temperature is higher, can play the role of sterilization, but also can make the heating water temperature is higher.
2, soften hard water, prevent the formation of scale. Add salt to the boiler feed water, so that with the boiler feed water into the furnace Ca2 + will not form scale, but to generate slag, and through the boiler to be excluded from sewage.
3, to prevent alkaline corrosion.
Expanded information:
1, in order to make the residual hardness of the boiler feed water smaller, should be in the softening treatment of feed water more than the removal of Ca2 +, Mg2 +, so as not to generate too much slag in the boiler water, increase the boiler's sewage and even affect the quality of steam.
2, should make the boiler water to maintain the required amount of excess phosphate. In addition, the dosing should be uniform, the speed can not be too fast, so as to avoid a sudden increase in the salt content of the water in the boiler, affecting the quality of steam.
3, should be discharged in a timely manner generated slag, so as not to set a lot of boiler water slag, affecting the quality of steam.
4, for the scaling of the boiler, phosphate dosing in the treatment, the scale must first be removed. Because the phosphate root can also play a role with the original calcium scale, so that the scale gradually become water slag off, so that the boiler water to produce a lot of water slag and affect the quality of steam, and in serious cases, the shedding of the scale will even block the furnace tube, resulting in water circulation failure.
5, add the drug should be relatively pure, so as to avoid impurities mixed into the pot caused by boiler corrosion and steam quality deterioration. Drug quality should generally meet the following standards: content of not less than 92%, insoluble residue is not greater than 0.5%.
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