Effect of scale inhibitor on biomass hot water hot stove
Biomass hot water stove chemical water treatment is a method of adding appropriate amount of scale inhibitor to the water to make it react with the hardness substance in the boiler water to produce loosely flowing water slag, thereby preventing the scaling of the biomass steam boiler The boiler dosing treatment method has the advantages of less investment, simple equipment, easy operation, and convenient management, but its scale prevention effect is slightly worse than the chemical treatment outside the furnace. For horizontal fuel steam boilers, the simple treatment of boiler water is only applicable to For vertical boilers with water-walled tubes, in addition, for sodium ion exchange treatment, when the residual hardness is large or the pH and alkalinity of the boiler water do not meet the standard requirements, the boiler needs to be added with medicine.
The main role of scale inhibitor
1. Reacts with hard materials to form water slag, remove sewage, and prevent fouling of biomass hot blast stove.
2. Maintain the alkalinity and pH of the boiler water.
3. A protective film is formed on the metal surface to prevent corrosion,
4. Make sulfate and silicate scale loose and fall off.
Common scale inhibitor
1. Soda ash (sodium carbonate) can be used alone, usually forming a compound scale inhibitor with other agents.
2. Phosphate is often used as a calibrator to eliminate residual hardness after chemical treatment outside the boiler, or as a component of the composite scale inhibitor using trisodium phosphate. When the alkalinity of water is high, hydrogen phosphate can also be used Disodium or disodium hydrogen phosphate to reduce alkalinity.
3. Compound scale inhibitor, select the appropriate scale inhibitor according to different water quality characteristics, and formulate according to the ratio.
4. Organic phosphonates, polycarboxylates and other organic scale inhibitors have the advantages of low dosage and good scale inhibition effect, but the price is more expensive. At present, biomass hot water stoves are still relatively few.
Dosage of scale inhibitor: According to the test results, the amount of scale inhibitor should be clarified. The pH value and alkalinity of boiler water after dosing should comply with national standards. Since sodium carbonate will be hydrolyzed to form part of sodium hydroxide at high temperature, scale inhibitors are generally composed of sodium carbonate, trisodium phosphate and tannin extract. The dosage can be determined according to the difference of total hardness and total alkalinity of water supply