Removing Scales from Fire Tube Boilers

There are Better Ways

Over the years, tube cleaning technology has made great strides in developing faster, easier and more efficient cleaning methods. Equipment is now available that enables a single operator to perform two tasks at once in a fraction of the time required for outdated cleaning methods.

For firetubes with soot deposits, there are tube cleaning machines that mechanically drive brushes or scrapers through the tubes requiring almost no human effort. These machines are, in turn, connected to powerful vacuums that draw the loosened soot from the tubes simultaneously, leaving the tubes, boiler room and operator completely clean.

Some firetube boilers develop scale deposits. This is particularly true with waste heat boilers and boilers fired on lesser quality fuels. Some of the worst waste heat boilers are found at hospitals where medical waste is burned in incinerators and the boiler is used to capture the heat generated by the incinerator. In many cases, a straight brushing action is not sufficient, and rotary tube cleaning equipment must be used. Manually fed rotary systems are available that incorporate simultaneous vacuuming as well. Many of these systems were based on designs originally intended for condenser and chiller tube cleaning and they work extremely well on scaled boiler tubes.

Systems are now available that utilize more powerful air motors which drive flexible shafts fitted with any of a variety of boiler tube cleaning tools. The flexible shaft is sheathed in a water tight casing which transports water right to the cleaning tool. This feature allows for the tubes to be cleaned and flushed in a single operation, saving time and labor.

About Chemical Cleaning Chemical cleaning has been used on boilers for many years and is periodically needed to clean the waterside of firetube boilers. Chemicals can effectively remove calcium carbonate and other scales that adhere to heating surfaces. Chemical cleaning should only be performed when deemed necessary and by technicians who are trained and equipped to do the work safely. Chemical cleaning presents the following challenges:

• Cost – chemicals are expensive
• Safety – chemicals present potential danger to personnel and equipment
• Environmental concerns – what if there is a spill?
• Disposal – the regulations concerning hazardous waste disposal are only growing
• Time – chemical cleaning can add up to a week to an outage

Considering these challenges, it is important to know when a boiler needs chemical cleaning. It is worse to chemically clean a boiler that does not need it than it is to not clean one that does. Improving water chemistry and lay-up and start-up practices can extend the time between cleanings.

A continuous treatment regime on the feed water will obviate the build-up of scale in the first place.

First what you need is to contact 2-3 very good Boiler Chemical Cleaning experts/Company to visit and carry out all tests to determine the present condition of scales. Compare the 3 findings and suggestions then decide to give contract.

Cleaning frequently is not a solution! You must ensure that the feed water is within dictated specification as per your Boiler manufacturer with:

1 . return all condensate to your boilers(ideal boiler feed)

2 . fabricate a feed tank cum de-aerator to utilize feed water +105C.

3 . install automatic boiler surface & bottom blow-down system.

scales in water side and its exist in a thick layer . can we do this chemical treatment by our boiler technician staff or it's necessary to invite a specialist company

thank you for yours contributions

boiler technician staff - if they were that good you'd not me in this sh-t.

or it's necessary to invite a specialist company- YES