| From the New Orleans True Delta |
| |
| September 2, 1863 |
| |
| Incrustation in Boilers |
| There has been brought
forward, of late years, a great variety of "incrustation
powders," some of which act on the well known principle of
enveloping the disengaged particles of solid matter in glutinone
coating, whereby they are prevented from adhering to the iron or to
each other. Where potatoes, leather, shavings, etc, are used for this
purpose, they are likely to cause priming, the remedy being as bad as
the disease. Highly astringent substances prevent incrustation, and
gum catechu -- cutch or terra japonica -- has been extensively
employed, and with good results, in locomotive boilers. One of these
anti incrustation powders has Aleppo galls for its base; this, too,
has done well. Oak or mahogany sawdust prevents scale, but, as is well
known, iron is rapidly destroyed when acted upon by the acids in oak.
The use of caustic soda has been recommended, but this remedy does not
appear to have been adopted to any extent -- its cost, and the
necessity for special provisions in applying it being in the way of
its use. For marine boilers, surface condensation is already providing
a supply of the purest water, and it is not improbable that surface
condensers, notwithstanding their cost , will yet be extensively
adopted for condensing land engines. With boilers of ordinary
construction, the tendency to incrustation increases with the pressure
of the steam, but in water-tube boilers, with a circulation of water
maintained forcibly by means of a circulating pump, the worst waters
are being employed with the formation of very little scale. A perfect
remedy is still a great desideratum. |
|