Which Oxygen Scavenger should be used in your boiler system? We help you evaluate your needs and give you the pro’s and con’s of commonly used oxygen scavengers.
It is well known that one of the greatest threats to the integrity of a steam system is corrosion due to the effects of dissolved oxygen. Oxygen corrosion can be severe, especially to mild steel and when high temperatures come into play – this corrosion can occur quickly. Therefore, it is important to take action to strip the feedwater of oxygen to prevent this metal loss. There are two techniques used to accomplish this:
- Physical removal using equipment such as a deaerator
- Chemical removal
Physical removal of the bulk of the oxygen is commonly used because it is much less costly than chemical removal alone. Although a properly operated deaerator can effectively remove oxygen to as low as 5 ppb, that level is still enough to cause significant damage in a boiler system. Chemical oxygen scavengers are therefore used to remove or “polish” these small amounts of oxygen remaining after the bulk of the oxygen has been removed through physical means.
There are a number of different chemical oxygen scavengers that are commonly used for treatment of boiler systems. They are listed below:
- Sodium Sulfite
- Erythorbate
- Diethylhydroxylamine (DEHA)
- Hydroquinone
- Hydrazine
- Carbohydrazide
- Methyl Ethyl Ketoxime (MEKO)
