Wood fire smoke fly ash contains caustic alkalis

Research studies on wood smoke and other air pollution.

Wood fire smoke fly ash contains caustic alkalis

Postby Wilberforce » Wed Jan 28, 2009 5:53 pm

Wood fire smoke fly ash

Certain trace elements are a component of plants. Calcium and potassium are the
predominant metallic elements present in common tree wood.

The study shows that high-temperature burn rates result in metal oxide formation,
some of which can be sent up the chimney as nanoparticle-sized fly ash. (most wood
ash remains in the furnace) The nanoparticle form of calcium oxide (Ca is prevalent
in all wood species) can be damaging to the respiratory tract if inhaled directly.
Calcium oxide is quicklime. In addition to having a powerful damaging dehydrating
effect, airborne lime, when inhaled, forms a hydroxide (a strong alkali) in the nose
and lungs due to the presence of moisture. This may be partially responsible for
the pungent, choking effect of significant concentrations of wood smoke.
Potassium oxide (K2O) is also present. This is a stronger alkali than CaO.

Wood ash composition as a function of furnace temperature
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Postby Wilberforce » Wed Mar 25, 2009 12:02 am

Comparison of several wood smoke markers and source apportionment methods for wood burning particulate mass
Sandradewi, et al
"The emission factors of potassium during wood burning have been shown to be
strongly influenced by the combustion temperature. Wood combustion at low temperature
result in less potassium mass per unit fine particles emitted, and vice versa (Khalil 5
and Rasmussen, 2003). The AMS measures potassium yet as a qualitative parameter
due to the incomplete volatilization of KCl and K2SO4, and the production of K+
ions by surface ionization. For the Zurich winter campaign in January 2006, a marked
degree of correlation (r2=0.67) between OMwb determined by factor analysis and the
measured AMS potassium was reported (Lanz et al., 2008)."


The study indicates that high temperatures (as in EPA wood stoves) emit higher amounts
of potassium (as oxide, hydroxide, chloride, and sulfate) than lower temperature burning.
These are nanoparticle-sized fly ash. As suggested before, this may account for the
choking effect of nearby wood smoke sources. The oxide and hydroxides of potassium
are caustic and extremely strong alkalis. They can damage skin and internal tissues.

K+ ions...Yet another poisonous chemical which is part of wood smoke!

"Severe irritant. Effects from inhalation of dust or mist vary from mild irritation to serious
damage of the upper respiratory tract, depending on the severity of exposure. Symptoms
may include coughing, sneezing, damage to the nasal or respiratory tract.
High concentrations can cause lung damage."
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Postby Wilberforce » Mon Apr 13, 2009 10:13 am

Fly ash

"In the past, fly ash was generally released into the atmosphere, but pollution control
equipment mandated in recent decades now require that it be captured prior to release."

note: while this may be true of coal combustion, as yet no law requires
the capture of fly ash originating from residential wood combustion.

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Potassium Hydroxide present in woodsmoke fly ash

Postby Wilberforce » Sun Jan 02, 2011 8:43 pm


The caustic alkali potassium hydroxide (KOH) is present as a large proportion of wood smoke
fly ash, especially at elevated burn temperatures of modern EPA stoves. When inhaled, the
vapor phase of KOH can cause alkali burns in the throat and lungs.

image source (color emphasis added)
• The Surgeon General has determined that there is no safe level of exposure to ambient smoke!

• If you smell even a subtle odor of smoke, you are being exposed to poisonous and carcinogenic chemical compounds!

• Even a brief exposure to smoke raises blood pressure, (no matter what your state of health) and can cause blood clotting, stroke, or heart attack in vulnerable people. Even children experience elevated blood pressure when exposed to smoke!

• Since smoke drastically weakens the lungs' immune system, avoiding smoke is one of the best ways to prevent colds, flu, bronchitis, or risk of an even more serious respiratory illness, such as pneumonia or tuberculosis! Does your child have the flu? Chances are they have been exposed to ambient smoke!
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