Although boilers are made of heavy-duty materials, they aren’t as indestructible as they seem. Without proper care and maintenance, you can destroy a boiler. From fuel explosions to contaminated feedwater, we are here to give you some tips on how to not destroy your boiler.
First, let’s talk about fuel explosions. One way to prevent a fuel explosion is to make sure that your fuel mixture is not too rich. A fuel mixture that is too rich can cause a buildup of unburned fuel, which can ignite and cause an explosion. Next, make sure your oil is being atomized properly. If it is not, oil can build up in the floor of the furnace and combust. Finally, purge your system when necessary to ensure that you do not have explosive levels of concentrated fuel in the furnace.
Moving forward, we will cover the issue of contaminated feedwater. Feedwater can become contaminated by oils, resin, oxygen, treatment chemical, metals, and other compounds. Oxygen is one big enemy here. Most boiler plants employ strategies to eliminate oxygen from tubes: a deaerating feedwater heater and a continuous feed of sodium sulfite are examples. Acid is another feedwater contaminant that can cause serious damage to a boiler. Prevent the introduction of acid into the system by performing regular maintenance to ensure that the system is not leaking, and use double block and bleed valves in places where regenerant chemicals are added to water that is used in the boiler. You must ensure that the feedwater is uncontaminated in order to keep your boiler functioning as effectively as possible.
Low-water conditions are another potential issue for your boiler. Water in a boiler keeps the steel that composes the boiler from melting. Prevent low-water conditions by regularly ensuring that your feedwater pump, control valves, drum level controller, and safety valves are working properly. In addition, make sure that the deaerator system receives a consistent supply of water, that the control valve actuator receives a consistent stream of air pressure and that the steam load for the boiler stays consistent. If you are using a trip circuit, check it regularly to ensure that it is working properly.
Next, perform blowdowns when necessary. Doing this will ensure that the water within the boiler does not contain an unacceptable number of solids, which can lead to sludge formation and corrosion.
When it comes to storing a boiler, store it in a hot standby whenever possible. This can be done by using mud drum heaters as well as sending the blowdown of a working boiler through the boiler being stored. This keeps you from running the risk of improperly warming up the unit.
In regards to warming up a unit that is coming out of storage, it is imperative to ensure that the warm-up process is completed slowly. All of the different components of a boiler heat up at different rates; by moving the boiler through a slow warm-up process, you prevent boiler damage in the immediate future and in the long run.
When employing the use of a sootblower, make sure that the jets do not blow directly on the tubes. If this does occur, the tubes can become damaged. If you use a sootblower with wet steam, ensure that condensate is removed from the steam lines by preheating the lines. It is important to understand that the tubes of a boiler are very fragile and can be damaged by seemingly miniscule impacts.
Finally, understand the capacity at which your boiler is operating. Most boilers can be operated above their Maximum Continuous Rated (MCR) capacity. However, this does more damage to the boiler and may require more short and longterm maintenance than operating the boiler at the MCR.
Boilers are not indestructible, but keeping yours working as effectively is not impossible. Keep these tips in mind, call in the experts when necessary, and be reasonable in what you demand of your boiler system, and it will reward you with a long and healthy life of service.