Hard water as cooling water of industrial production, can make the scale heat exchanger, the serious will not only hinder the water channel, make the heat exchange effect is greatly reduced, affect the production run smoothly, and even forced to stop production.Scale also can produce corrosion under the scale, can make heat exchanger perforation and damage, not only material leakage, and increase the equipment investment cost, waste steel.Hard water used for washing, tend to affect the quality of the product, such as textile dyeing and printing will cause fabric spots, not only affect beautiful, and impact strength.Hard water as boiler water in the pot after heating, evaporation and concentration process, after the boiler heating surface furring, and scale of the thermal conductive performance is poor.
Scale heat conduction performance of the only few one percent steel.Within the boiler scale, when there is no scale if you still want to achieve the same boiler water temperature, is bound to increase the wall temperature of heating surface, for example, 1.01 Mpa (10 ATM) boiler, wall temperature is 280 ℃, when silicate scale up to 1 mm thick, to achieve the same boiler water temperature, wall temperature will increase to 680 ℃, the strength of the steel plate at this time since 3.92 Mpa (40 KGF/cm2) fell to 0.98 Mpa (10 KGF/cm2), serious can cause blowout accident.Metal temperature will cause the metal elongation, 1 m long steel plate, every rise 100 ℃, the elongation of 1.2 mm, increase the material stress and cause damage.In addition, the scale, make the heating surface heat transfer conditions deteriorate, heat of combustion cant very well to the water, reduce the thermal efficiency of boiler, and a waste of fuel, such as sulphate scale knot is 1.5 mm thick, waste fuel by more than 10%, and the output of the boiler is greatly reduced.Furring, still have to often clean, not only affect the production, and reduce the service life of the boiler, but also cost resources.Hard water to the harm of the industrial production, therefore, must according to the requirement of the product or equipment for water quality, to soften hard water, in addition to salt or other effective water treatment. |