Cooper J.A., Environmental Impact of Residential Wood Combustion Emissions and its Implications, Air Pollution Control Association Journal, 30 (8), 855-861, 1980 Aug.
Extracts
"The chemical products
formed in the combustion of wood have been studied primarily in terms of the
major products of combustions such as water and carbon dioxide and minor
components such as CO, HCl, SOx, NOx, etc. Two recent studies however measured
over a hundred different chemicals and compound groups in emissions from burning
wood and wood-burning stoves. The results from these studies showed smoke from
wood and wood-burning stoves and fireplaces contained
Other toxic gases such as CO, noxious and respiratory irritants such as aldehydes, phenols, etc were also found. Even dioxins have been identified in fireplace soot."
Wood-burning stoves |
Fireplaces | |||
Chemical Species | g/kg wood | % particulates | g/kg wood | % particulates |
Carbon monoxide | 160 | 22 | ||
Volatile hydrocarbons | 2 | 19 | ||
Condensable organics | 4.9 | 58 | 6.7 | 74 |
Particulates | 3.6 | 42 | 2.4 | 26 |
Total particulates | 8.5 | 100 | 9.1 | 100 |
Polycyclic organic material | 0.3 | 3.5 | 0.03 | 0.3 |
Benzo(a)pyrene | 0.0025 | 0.03 | 0.00073 | 0.008 |
Carcinogens | 0.038 | 0.45 | 0.0059 | 0.06 |
Priority pollutants | 0.41 | 4.8 | 0.063 | 0.7 |
Organic carbon | 4.2 | 49 | 4.2 | 46 |
Elemental carbon | 0.7 | 8 | 1.2 | 13 |
Note: This paper was published in 1980. An AS4013 stove must emit less than 5.5 g/kg of particulates, averaged over low, medium and high burn rates. Thus a correctly-operated AS4013 stove should have at least 35% fewer emissions. However, low burn rates produce significantly worse emissions. A stove rated at 5 g/kg would probably emit similar amounts of pollution to the above table on low burn rate. If operated incorrectly (eg by loading wood and not keeping on the highest possible setting until 20% of wood had been consumed), emissions could be 10 times higher than the table.
Polycyclic aromatic hydrocarcarbon emissions from
woodstoves vs open fires and enclosed coal stoves was also investigated by: I H
Zeedikj (1985). Polycyclic armomatic hydrocarbon concentrations in smoke
aerosol of domestic stoves burning wood and coal. Eindhoven University of
Technology, Dept. Chemical Engineering, Laboratory of Instrumental ANalysis, PO
Box 153, The Netherlands.
This extract shows Table 3 from his paper. Zeedikj notes that polycyclic
aromatic hydrocarcarbon (PAH) emissions from woodstoves vary a factor of 2.4,
according to the burn rate and the burn cycle. Emissions are much lower in the
latter part of the cycle. Zeedikj reported average over all burn rates and
sampled the entire cycle. This, or simple sampling variation, may explain the
difference between estimates of 5.8 mg of benzo(a)pyrene per kg of fuel from
Zeedijk vs 2.5 mg/kg from Cooper above.
(The first four -
benzo(a)pyrene, benzo(k)fluoranthene, dibenzo(a,h)anthracene and
benzo(g,h,i)perylene are highly toxic)
Wood stove
Fireplace
Coal stove
benzo(a)pyrene
5.8
0.5
1.0
benzo(k)fluoranthene
11.2
0.3
1.6
dibenzo(a,h)anthracene
1.7
0.1
1.2
benzo(g,h,i)perylene
13.0
0.3
1.4
fluoranthene
12.5
2.3
1.5
pyrene
15.8
2.9
6.4
benzo(a)anthracene
3.7
2.0
2.8
chrysene
16.3
2.2
9.9
benzo(b)fluoranthene
11.2
0.3
1.6
indeno(1,2,3,c,d)pyrene
4.7
0.4
3.9