Boiler Chemical InjectionHow do I inject my boiler chemical?
First, determine the type of boiler you have. It is either a hot water boiler or a steam boiler. Both of these systems chemical feed is drastically different.
What is a hot water boiler?
A hot water boiler is a boiler that does not generate steam. Rather it only recirculates hot water throughout the piping in the building. Examples how hot water is used:
What is a steam boiler?
- Heat the building or facility
- Directly heat the manufactured product with a closed loop water loop that goes back to the boiler
- Heat an intermediate heat exchanger
- CIP cleaning
A steam boiler is a boiler that generates steam. Examples how the steam may be used:
- Direct steam humidification
- Heating of heat exchangers within the building
- CIP cleaning
- Direct steam injection into the final product
- Heating of intermediate heat exchanger
How do I inject the boiler chemical into a hot water boiler?
Regardless, if the boiler system is new or old a ideally a chemical pot feeder should be used to inject the hot water boiler chemical into the system. Chemical pot feeder come in sizes from 2 to 12 gallons. The larger the water system, the larger the preferred unit (saves time refilling the unit). Neptune Chemical Feeders are the most popular chemical feeders.
Example: If you have a 1,000 gallon water system, use a smaller pot feeder, since it may only need to be filled a few times in order to reach proper chemical residual levels.
If you have a 100,000 gallon water system, you may consider purchasing a large unit to decrease the number of times the unit needs to be refilled before reaching proper dosage rates.
If you do not have the funds to purchase a chemical pot feeder, you may inject the chemical with a chemical metering pump or AOD pump anywhere in the piping through a chemical injection quill.
How do I inject steam boiler chemicals? Steam boiler chemicals are much different then hot water boiler chemicals. To keep it simple we will just concentrated on boilers less then 200 psi, since this 95% of the boilers out there. There are four main components used to treat steam boiler chemicals oxygen scavengers, alkalinity builders, condensate treatment, and polymer or phosphate boiler chemicals. Here are the ideal feed points for each individual component:
- Oxygen Scavenger (Sulfite) - Feed to the center of the storage section of the dearator or feed water tank with an injection quill.
- Alkalinity Builders (Sodium or Potassium Hydroxide) - Feed to the dropleg pipe coming from the deaerator or feedwater tank with an injection .
- Scale Prevention (Phosphates or Polymers) - Feed to the feed water line after or before the feed water pump.
- Condensate Treatment (Amines) - Feed directly into the center of steam header with a retractable corporation stop valve.
If you have problems injecting into the ideal location, you can always feed them to the storage section of the deaerator. The main thing is to feed the chemical into center of the pipes or center of the feedwater tank. This will ensure a good chemical mixture.
If you feed the amine to the feedwater tank or line, you will lose around 10% efficiency. That is you will use 10% or more to get the same result.
Smaller steam generation boiler may use "All in One" boiler chemical drums to reduce chemical drum handing and to reduce the number of chemical drums on site. If this is your case, feed this chemical to the center of the feed water tank.