Page 176 - Boiler plant and distribution system optimization manual
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Over 100 Ways to Improve Efficiency 161
question is, “How much of this expensive steam
is really being put to productive use and how
much is being lost?” When the potential for loss
is documented, it often has become obvious that
a good maintenance programs are required.
Advantages/Disadvantages
Until the potential savings of good steam
trap maintenance is realized by management, big
energy dollars will be silently lost in distribution
systems.
4. REPAIR ExISTING INSULATION
Cost
Moderate
Potential Savings
Good return on investment
Description
Boilers and steam systems have metal sur-
face temperatures from 350°F to 450°F and above
Figure 10.57—Bare pipe heat losses
and must have effective insulation to prevent
heat from escaping from boiler and piping sur-
Description faces. Some older systems have many miles of
Steam traps can waste a tremendous amount piping which has been exposed to harsh weather
of energy; even when working properly steam conditions for decades. Infrared instruments are
traps are inefficient when you consider the flash useful in determining these losses and some are
losses. Traps may go through millions of cycles a calibrated to indicate Btu losses per hour from
year and develop leaks and many types have high hot surfaces which is very useful for cost/benefit
failure rates. Industrial studies have shown that analysis. Figure 10-…… can be used to assist in
large savings are possible with proper steam trap estimates.
maintenance programs.
Many condensate systems are “open” which Advantages/Disadvantages
means that they vent to atmosphere. Because of Asbestos may be encountered in older sys-
the high pressure on the working side of the trap tems. Insulating bare steam piping is usually a
and the low pressure on the outlet side, over 10% quick pay back item.
of the condensate going through healthy traps
will flash into steam representing a lot of heat
that eventually gets lost from the system. Add to 5. OPTIMIzE CONDENSATE RECOVERY
this the many problems found in traps, like clos-
ing slowly, allowing steam to escape, leaky seats The “pure” water from the condensed steam
or just not closing at all and it becomes obvious still contains valuable energy after it leaves steam
there is a potential for large hidden steam losses, traps and for efficient operation it should be re-
maybe over 50%. Extensive studies have shown covered and arrive back the boiler plant where it
that in most plants, a very high percentage of is reheated into turned back into steam and recy-
traps have failed one way or the other. The real cled in the steam system over and over again.
