Boiler water treatment plays a vital role in ensuring the efficient operation and longevity of boilers. Improper water treatment can lead to serious problems such as scaling, corrosion and premature failure of boiler components. Unfortunately, many facilities struggle to properly manage boiler water treatment, resulting in operational inefficiencies and costly repairs. This article discusses six common boiler water treatment problems and suggests effective solutions to address them.
1. Lack of implementation of boiler water treatment
In many cases, small or seasonal boilers do not receive the attention they deserve. The personnel managing these boilers may lack the necessary experience and fail to implement proper water treatment. This often leads to the accumulation of scale and corrosion, which, over time, severely affects the performance of the boiler.
The solution:
For small-capacity boilers or those that are used intermittently, a comprehensive approach to water treatment should be considered. For small, low-pressure steel-shell boilers, external chemical treatment methods should be used and oxygen removal equipment should be installed. Large boilers with higher evaporation rates and steam pressures require both external chemical treatment and oxygenation equipment. For natural water sources with high levels of impurities, pre-treatment measures such as sedimentation or filtration should be implemented to ensure effective boiler water treatment.
2. Improper boiler water treatment methods
To reduce costs, some companies may resort to unscientific methods of boiler water treatment, often using non-compliant or inferior equipment and chemicals. For example, the use of “three-no” (non-registered, non-certified and non-standardized) electronic anti-scaling devices or unauthorized anti-scaling chemicals is a common cost-saving strategy. While this may reduce initial costs, it often exacerbates scaling and corrosion problems, wastes energy and reduces boiler life.
The solution:
A revised approach to boiler water treatment is essential. Any new treatment technologies should be approved by the relevant authorities and properly documented. Once an effective treatment method has been established and certified by technical authorities, it should be promoted for wider use. Ensuring that treatment methods meet established standards is critical to the safe and efficient operation of the boiler.
3. Neglecting the pH of boiler water
Boiler water hardness is a critical parameter that directly affects the likelihood of scale formation and corrosion. If the hardness of the boiler water is too high, this can lead to scaling as the water evaporates. In hot water boilers, high hardness also accelerates corrosion, leading to damage and reduced operational efficiency.
Solution:
To reduce the risk of scaling and corrosion, the pH of the boiler water should be maintained between 10 and 12. If the water hardness is too high, appropriate doses of soda can be added to raise the pH to the desired range. Regular monitoring and adjustment of the pH is essential for optimum boiler performance.
4. Problems with boiler water treatment equipment
The effectiveness of boiler water treatment is highly dependent on the quality of the equipment used. Poor quality water treatment equipment can result in inadequate treatment, increasing the risk of scale and corrosion. Common problems include improper use of resin exchangers, oxidation of resin due to exposure to air, and iron poisoning of resin due to untreated iron deposits. In addition, the use of untreated river water without adequate filtration can clog the resin and reduce its effectiveness.
Solution:
Appropriate measures should be taken to ensure effective water treatment. For example, external chemical treatment should be used when using resin exchangers. In cases of resin iron poisoning, a thorough analysis is required to identify the cause and develop solutions to rejuvenate the resin. Regular maintenance of anti-corrosion equipment, including timely inspections and protective measures, is essential to prevent resin degradation and maintain water treatment efficiency.
5. Inadequate water quality testing and management
A common problem in boiler water treatment is the lack of strict quality control over the water testing process. Some plants fail to set clear standards for key indicators such as hardness, alkalinity and pH levels in both feedwater and steam. Inadequate or untrained personnel can also falsify test results or neglect the importance of accurate testing, undermining the effectiveness of water treatment.
Solution:
To address these shortcomings, organizations must implement a more rigorous water quality testing and management system. Senior management should recognize the critical role of proper water treatment in ensuring the safe and efficient operation of the boiler. Water quality testing personnel should undergo regular training and certification to ensure they understand the importance of accurate data collection and testing protocols. In addition, management should enforce strict guidelines for water quality testing to ensure regular monitoring and timely correction of any anomalies.
6. Inadequate boiler blowdown procedures
Boiler blowdown is the process of removing water from the boiler to reduce the concentration of dissolved solids and contaminants that accumulate over time. Improper blowdown practices can result in either excessive heat loss or inadequate fouling removal. Some operators avoid blowdowns to save energy, while others perform excessive blowdowns, resulting in significant heat loss.
Solution:
To optimize blowdown procedures, a balance must be struck between saving energy and maintaining water quality. Boilers with both bottom blowdown and continuous surface blowdown should perform at least one blowdown per shift. Boiler water should be tested every one to two hours to monitor parameters such as hardness, alkalinity and pH. If any parameter exceeds standard limits, immediate adjustments should be made to the blowdown process. Boilers equipped with bottom blowdowns should only increase the frequency of blowdowns based on water quality analysis to maintain the desired water chemistry.
Conclusion
Boiler water treatment is a critical aspect of maintaining efficient boiler operation. The problems discussed above – from lack of water treatment implementation to improper blowdown procedures – can have serious consequences, including scaling, corrosion, wasted energy and reduced boiler life. By implementing appropriate solutions such as comprehensive water treatment plans, improved testing and management practices, and regular equipment maintenance, facilities can ensure the efficient and safe operation of their boilers. Proper attention to water quality and treatment practices will ultimately extend boiler life, reduce operating costs and improve overall system performance.