Oxygen Scavenger Properties

Oxygen Scavengers - Frequently Asked Questions
As a means of addressing concerns about using hydrazine as an oxygen scavenger and to compare several competing products, Arch Chemicals, Inc., has prepared the following questions and answers to aid in your decision making about oxygen scavengers. Hopefully they will dispel some of the concerns associated with using ScavOx® 35% hydrazine for your boiler application.

Q. What is an oxygen scavenger?
A. Oxygen scavengers are chemicals added to boiler feedwater or condensate return to remove residual dissolved oxygen.

Q. Why use an oxygen scavenger?
A. Dissolved oxygen can cause extensive corrosion damage at the high temperatures and pressures encountered in utility boilers and must be removed.

Q. What are the properties of good oxygen scavengers?
A. They should react rapidly with oxygen, passivate steel surfaces, have some volatility, add no solids, carbon dioxide or organic acids to the water and can be safely handled.

Q. What products meet all these criteria?
A. None meets them all completely, but hydrazine offers many advantages.

Q. Aren't there some concerns about hydrazine?
A. Yes, hydrazine fumes can be a concern, but modern, closed handling systems offered by Arch Chemicals, Inc. can practically eliminate worker exposure. With good work practices, many hazardous chemicals are routinely handled safely. Arch has produced a training/information CD on hydrazine safety and handling for customers to use at their sites.

Q. What type of closed containers are available from Arch?
A. Scav-Ox ® hydrazine comes in returnable, stainless steel tote bins. They are completely closed and have dripless, quick connect fittings. Their 180- and 350 gallon size eliminates drum handling and disposal. For smaller applications, EZ Drum™ containers are available. They offer a closed handling system in a 55 gallon size.

Q. Where can I obtain these closed systems?
A. Please contact us for additional information.

Q. What about your treatment cost?
A. When one takes into account all factors, such as: low equivalent weight of hydrazine; lack of by-product carbon dioxide or organic acids, which require the use of additional chemical treatment; and chemical price; the cost is very favorable.