Page 46 - Boiler Operator’s Handbook

Operating Wisely 31

lished so far out in front of the burner that it would local boilers is seen as a way to reduce the capital (first)
not light the first two or three tries; an accumulation of cost. We can install one gas pipe distributing fuel to all
unburned fuel brought the mixture into the explosive those local boilers at a much lower cost than installing
range on the next attempt and the boiler room walls flew insulated steam and condensate or hot water supply and
out into the parking lot. That incident and several others return piping.
I’ve investigated justifies my instructions to all boiler However, the cost of several small boilers with a
operators. The best thing I can tell you at the end of a combined capacity exceeding that of the central plant
chapter on combustion. You can push the reset push- puts a considerable dent in the distribution piping sav-
button on the flame detector chassis two times and only ing. Those are not the principal reasons for the switch;
two times, never take a chance on strike three. the main reason central plants are abandoned is the
I can’t leave the subject of combustion without contention that all those little local plants, operating
touching on the latest buzzwords that has EPA’s atten- a low steam pressure or with hot water below 250°F
tion and, therefore, every State’s department of air qual- don’t need boiler operators present. The justification is
ity. Combustion optimization is simply the process of eliminating the high wages of boiler operators. There’s
adjusting the air to fuel ratio on a boiler to get the most the main source of the false economy. Installing many
heat out of the fuel. The environmental engineers also more boilers to maintain will reduce the cost of qualified
want it to be while generating the smallest amount of operators. Ha!
emissions. For many a small plant a service technician The most recent study I’m aware of is one by Servi-
comes in once or twice a year (the typical state regula- dyne Systems Inc., & the California Energy Commission
tion requires a combustion analysis at least once a year) which claims “a well trained staff and good PM pro-
and he “tunes up” the boiler. From all I can tell that’s the gram has potential of 6% to 19% savings in energy.” If
EPA’s perception of it. Those of you with more sophisti- the staff is eliminated then an increase in cost of 6.3% to
cated controls and oxygen trim have automatic combus- 23.4% is possible because they are not there to maintain
tion optimization, the controls are constantly adjusting that savings. A little plant with a 500 horsepower boiler
the fuel to air ratio. load could see energy cost increases in terms of 2013 dol-
lars of $46 to $171 per day in fuel alone. That’s consider-
ably less than the numbers quoted in the first edition of
THE CENTRAL BOILER PLANT this book because fracking has increased the production
of natural gas dramatically thereby forcing the price of
Steam and hot water are used for building and gas down. I have to admit that a plant has to have an
process heating because the conversion of our fossil average load closer to 1500 horsepower to justify the
fuels (coal, oil, natural gas) and biomass (like wood and expense of Licensed Operators by fuel savings alone but
bagasse) to heat is not a simple process. Water and steam there’s much more to be saved by knowledgeable opera-
are clean and inexpensive and are excellent for transfer- tors and, in my humble opinion, disposing of a central
ring energy from one location to another. It is also rela- plant isn’t justified if it’s load is greater than 500 boiler
tively easy and inexpensive to extract the heat from the horsepower.
steam or hot water once it has been delivered to where Fuel prices in January of 2001 were triple the 1999
the heat is required. Boilers made it possible to central- cost and they’re increasing again as I write this. So, you
ize the process for converting fuel to heat so the heat see, decentralizing almost any existing plant will save
could be distributed throughout a facility for use. One on labor but burn those savings up in fuel. That doesn’t
boiler plant in a large commercial or industrial facility consider the additional cost of maintaining several boil-
can serve hundreds or even thousands of heat users. The ers instead of two or three. By the time all those local
central plant concept is the most efficient way to deliver boilers start needing regular maintenance the people
heat to a facility. that decided to eliminate the central plant have claimed
Many will question that statement, I know. If cen- success and left. The facility maintenance bill starts to
tral plants are so efficient then why are so many facilities climb to join the high fuel bills associated with all those
installing local boilers and doing away with the central local boilers.
plant? The answer is false economy. Many of our central Now someone’s going to claim that the local boil-
plants are at the age where all the equipment and pip- ers are more efficient because they’re operating at low
ing are well past its original design life and should be pressure. That’s not true. Nothing prevents a high pres-
replaced. Replacing the central plant with several small sure steam plant with economizers generating steam