Page 154 - Boiler plant and distribution system optimization manual

Over 100 Ways to Improve Efficiency 139

Figure 10.34
various types of firetube boilers with turbulators installed

7. CLEAN FIRE-SIDE DEPOSITS 8. CHECK FOR HOT GAS SHORT CIRCUITS
TO IMPROVE HEAT TRANSFER INDICATING DEFECTIVE BAFFLES

Fireside deposits are quite varied depending Boilers are designed to absorb heat from
on the fuel source, especially Coals and Heavy combustion gases with great efficiency. These hot
Fuel Oils (HFO). Slags get so bad sometimes they gases are guided on their way through the boiler
have to be removed with dynamite or shotgun by baffles that on occasion break down and let hot
blasts. In lesser cases, high pressure water wash gasses pass without giving up their heat.
can be used. Also, fuel additives are used to help Hot gas short circuits can be detected by
with this process. doing a temperature traverse across the out-
The key here is rising exhaust temperatures; let breechings. Wherever the gases are leaking
every 40°F the temperature rises costs 1% in boiler through the baffles they are causing a hot flow
efficiency so it is an basically an economic judg- lanes which can be detected by taking tempera-
ment when to curtail operations and do a clean- ture measurements. So it is a matter of system-
up. This could have an important impact on the atically probing the cross section of the exhaust
economy of operations and profits. section searching for hot spots. Specific repairs