The boiler water hardness is too high

Chemical addition and slag removal are actually methods for water treatment inside drum boilers; sodium tripolyphosphate is commonly used to convert the scaling substances in the boiler into sludge or dissolve them, so that they can be removed from the boiler through the slag removal system, thereby achieving the purpose of water treatment within the boiler.

The hardness of water used in industrial boilers generally refers to the amount of calcium and magnesium ions present in the water that has been treated by water treatment equipment before being used in the boilers. Under normal conditions, it is influenced by various factors such as changes in the quality of groundwater, the design and structure of sodium ion exchangers, their height, the water distribution system, the quality of the resin, the amount of resin used, whether the exchanger is contaminated, the degree of regeneration, the method of regeneration, whether there are leaks in the water softening tank, and whether the hardness of the returned water exceeds the specified limits. In addition, the accuracy of these measurement values is also affected by factors such as whether the testing chemicals are expired or accurate, the testing methods employed, and the skills of the personnel conducting the tests. Chemical dosing generally refers to the addition of \"trisodium compounds\", which do not contain calcium or magnesium ions; therefore, it is unrelated to hardness, and is only related to factors such as alkalinity and pH value. Waste discharge is related to the quality of boiler water, alkalinity, pH value, suspended solids, dissolved solids, etc., but not to hardness.

The dosage of chemicals should be adjusted according to the standards. Waste discharge can be done either periodically or continuously; periodic discharge is mainly used to remove sludge, while continuous discharge is used to remove water containing high levels of salts at the steam-water interface in the boiler drum.

The hardness of the boiler water depends mainly on the quality of the feedwater; if the quality of the feedwater cannot be ensured, or in the case of large-capacity superheated steam boilers, there are chemical dosing systems installed inside the boiler； To ensure the safe operation of the boiler and the quality of the steam. In the case of hot water boilers, most heating boiler rooms use chemical treatment added to the circulating water.

Chemical addition is divided into ammonia addition and phosphate addition. Ammonia is generally added at the deaerator outlet to control the pH of the feedwater. Phosphate addition takes place in the drum, where it enables coordinated control of the boiler water pH and the removal of calcium and magnesium ions. Wastewater discharge is divided into fixed-discharge and continuous-discharge types. It is located at the very bottom of the boiler’s evaporation equipment to remove water sludge and similar substances, while continuous drainage is generally used to control parameters such as the pH and conductivity of the boiler water.

Hardness is mainly caused by the carbonates of calcium and magnesium in water. Hardness is generally divided into temporary hardness and permanent hardness. It has high hardness, allowing for an increased amount of waste discharge and the use of more trisodium phosphate. What is more important is the pretreatment of deoxygenated water.

There is no indicator for boiler water hardness among the control parameters. As long as the water hardness is within acceptable limits – for example, less than 2 micromoles/L in the case of medium-pressure boilers – and the content of trisodium phosphate meets the required standards, the boiler water may have some hardness, but it won’t be too high, nor will it cause any significant problems.

Deoxygenation is not carried out; the dissolved oxygen in water is highly corrosive after steam is generated, so deoxygenated water should be used； Therefore, the boiler water needs to be deoxygenated.