Compared with hot water boilers, steam boilers have the disadvantages of difficult management and large energy consumption, while hot water boilers are relatively energy efficient, and their operation and management are relatively simple, with significant economic and social benefits. Although the upgrading of boilers is inevitable, many factories still have a lot of steam boilers. In order to allow some boilers to continue to play “waste heat” and reduce waste to a large extent, it is also a very good choice to transform steam boilers into hot water boilers. .

The transformation of steam boilers into hot water boilers is not only conducive to saving energy and reducing coal consumption, but also to the development of the current low-carbon economy. So what should be paid attention to when transforming a steam boiler into a hot water boiler?

1. Problems that should be paid attention to when changing to natural circulation hot water boilers: As we all know, natural circulation hot water boilers rely on the gravity difference formed by the temperature of the water in the circulation circuit to circulate. Therefore, when reforming the boiler, we must first consider Reliability of water circulation after changing to hot water boiler. To this end, attention must be paid to the following aspects:

1. Install a partition in the upper pot to divide the pot water into hot water area and cold water area. The return water of the system must enter the cold water area, and the hot water sent to the hot users should be drawn out from the hot water area. At the same time, the steam-water separation device in the boiler of the original steam boiler was removed.
2. After conversion to a hot water boiler, the safety and reliability of the boiler water circulation must be checked, that is, whether the natural circulation flow head caused by the difference in water gravity can overcome the circuit resistance, and there should be enough circulating water to pass through the pipeline. Keep the heating surface cool.
3. During the modification, a water distribution device should be added in the drum to prevent the return water from entering the hot water outlet pipe, and to ensure that the return water is sent to the down pipe, so that the inlet temperature of the down pipe is lower.
4. When the steam boiler is changed to a hot water boiler, the sewage system must be kept in order to regularly discharge sewage during the operation of the hot water boiler.
5. Due to the large amount of water in the hot water boiler, when the original steam outlet pipe and feed water introduction pipe are changed to the hot water boiler outlet pipe and the return water introduction pipe, the pipe must be enlarged according to the regulations of the hot water boiler for the water speed in the above pipeline. path.
6. For boilers equipped with economizers, in order to avoid excessive flow resistance of the economizer working fluid, it is necessary to connect economizers in parallel or increase bypass pipes.

2. Problems to pay attention to when transforming into a forced circulation hot water boiler: When the steam boiler is changed to a forced circulation hot water boiler, the system return water is sent to the lower boiler barrel, or separately to the lower boiler barrel and the header under the water-cooled wall. Water is drawn from the upper pot, and the heated surface of the boiler after the conversion is composed of many parallel pipe groups.

Pay attention to the following issues when modifying:

1. The thermal deviation of each parallel heating pipe group should be minimized. To this end, the return water of the system entering the boiler should be adjusted and distributed. For general low temperature hot water boilers, the hot water flow is large, and natural distribution can be used, that is, the amount of water entering each parallel tube group is naturally distributed according to the heating conditions of each tube group and the size of the pipeline resistance. Although the natural distribution is simple in structure, the safety and reliability of boiler operation is poor. For high-temperature hot water boilers, the relative amount of water is relatively low. Natural distribution should not be adopted. Instead, distribution should be adjusted by valves. Circulating water volume to ensure that the water temperature at the outlet of each parallel circuit is not significantly different. At this time, the deviation of the water temperature at the outlet of each circuit can be controlled within 10 degrees Celsius.
2. A certain water flow rate must be maintained in the heated pipe of the converted hot water boiler to ensure the cooling of the heated pipe and prevent oxygen corrosion and the deposition of impurities in the water. Sufficient water speed should be maintained for the downward heating pipe.
3. After the modification, the stagnation zone of water in the drum should be minimized, especially at the end of the drum, otherwise it is easy to cause oxygen corrosion. In order to be able to exclude the gas precipitated in the water in time, it should be at the higher point of each circuit Set the exhaust valve.
4. When refitting into a forced circulation hot water boiler, measures should be taken to prevent sudden power outages and vaporization of the boiler water when the pump is stopped.

• 
  How to Maintenance During Hot Water Boiler Shutdown Period
• 
  Let you know the advantages of hot water boiler applications
• 
  Do you know what scales are there in hot water boilers?
• 
  Hot water boiler heating knowledge essentials