Whether the water quality in industrial boilers meets standards directly affects the safe operation and service life of the boilers. Many people overlook water treatment, resulting in substandard water quality that triggers a series of malfunctions and causes unnecessary losses. Below, we will explain in detail the hazards of substandard water quality and methods for addressing them—please be sure to take this seriously.
I. Hazards of Substandard Water Quality
Hazard 1: Scale formation reduces thermal efficiency. Substandard water quality (excessively high calcium and magnesium ion content) leads to scale formation on the boiler’s heat transfer surfaces. Scale has an extremely low thermal conductivity, hindering heat transfer and resulting in reduced boiler thermal efficiency and increased fuel consumption. A 1-millimeter-thick layer of scale can reduce thermal efficiency by 5%–10%.
Hazard 2: Corrosion of boiler components, shortening service life. Substandard water quality (excessively low pH or excessive dissolved oxygen) accelerates the corrosion of the boiler’s metal components, leading to pitting and perforations in the heat transfer surfaces and piping. This shortens the boiler’s service life, increases maintenance costs, and may even necessitate the premature replacement of boiler components.
Hazard 3: Causes safety incidents. Scale can lead to localized overheating of the boiler’s heat transfer surfaces, causing pipes to burst; corrosion can cause component failure, leading to working fluid leaks. Leaks of high-temperature, high-pressure working fluid can result in safety incidents such as burns and explosions; substandard water quality can also cause unstable boiler operation and excessive parameter fluctuations, increasing safety risks.
Hazard 4: Impact on Energy Supply Quality. Substandard water quality can lead to steam carrying water (in steam boilers) or fluctuations in hot water temperature (in hot water boilers), affecting energy supply quality and, consequently, production. For example, steam carrying water can damage heat-using equipment and reduce product quality.
II. Methods for Addressing Substandard Water Quality
Method 1: Implement effective water softening. For water with excessively high calcium and magnesium ion content, use an ion exchange unit to soften the water by replacing the calcium and magnesium ions, thereby reducing water hardness and preventing scale formation. Replace the ion exchange resin regularly to ensure effective softening, and monitor water hardness daily to ensure compliance with standards.
Method 2: Implement effective deoxygenation. For water with dissolved oxygen levels exceeding standards, use methods such as thermal deoxygenation or chemical deoxygenation to reduce dissolved oxygen content and prevent oxygen corrosion; regularly add deoxygenating agents and test dissolved oxygen levels to ensure compliance with standards.
Treatment Method 3: Adjust the water’s pH level. If the water’s pH is too low (excessively acidic), add alkaline substances such as sodium hydroxide solution to adjust the pH to the specified range (pH 10–12 for steam and hot water boilers); if the pH is too high, add an appropriate amount of acidic substances to adjust it to the normal range. Test the pH regularly and make timely adjustments.
Treatment Method 4: Perform regular blowdown and water replacement. Periodically open the blowdown valve to remove scale, impurities, and substandard water from the boiler to improve water quality; regularly replace the water in the boiler to prevent water quality deterioration. When performing blowdown, control the volume and duration of blowdown to avoid disrupting normal boiler operation.
Method 5: Replace the make-up water. If the quality of the make-up water is extremely poor and cannot be brought up to standard through treatment, replace the make-up water source with a qualified one to prevent substandard water from entering the boiler.
Note: Conduct daily water quality monitoring and perform regular water quality tests. If substandard water quality is detected, take corrective measures promptly to prevent further damage. Water treatment equipment must be maintained regularly to ensure normal operation, thereby guaranteeing the safe and stable operation of the boiler.
