Effect of Wood Fuel on the Emissions from a Top-Feed Pellet Stove

Abstract

Particle and gaseous emissions of a top-feed pellet stove were studied in laboratory conditions. Pellets made of separate stem and bark materials of five different wood species and a commercial pellet product were used as fuels. The study included the determination of the particle number concentration, size distribution, fineparticle mass (PM1.0), CO, CO 2 , NO x , and volatile organic compounds (VOC). The PM1.0 emission was analyzed for inorganic substances, organic carbon, and elemental carbon. Thermodynamic equilibrium calculations were performed to interpret the results from chemical analysis and to estimate the chemical composition of the PM1.0 mass emitted with various fuels. The bark fuels produced higher PM, VOC, and CO emissions than stem fuels. This was evidently related to the higher ash content of the bark fuels and was found to increase both the fly ash emission and the products of incomplete combustion. The fuel ash content correlated linearly with the PM1.0 emission. Among stem fuels, willow and alder produced higher PM1.0 emissions than birch, pine, spruce, and the commercial fuel. An exceptionally low PM1.0 emission was measured from pine bark combustion, which can be explained by the low ash content of the fuel. The main components in the PM1.0 were K 2 SO 4 , KCl, K 2 CO 3 , KOH, and organic material. Except birch fuels, around 60-80 mass % of potassium species were K 2 SO 4 based on the equilibrium calculations. In the case of birch fuels, because of the high chlorine content and low S/Cl ratios, around half of the potassium was KCl.

Gas–Particle Distribution of PAHs in Wood Combustion Emission Determined with Annular Denuders, Filter, and Polyurethane Foam Adsorbent

“…The facilities are described by Sippula et al (2007) in greater detail. The emissions of CO, CO 2 , NO x , and several VOCs were measured and a wide range of fine particle measurements and analyses, including, for instance, particle mass, number, size distribution, morphology, OC/EC, ions, and ash were conducted.…”

Influence of the Burning Temperature of the Non-Volatile Combustible Content of Wood and Bark of Plantation-Grown, Fast-Growing Tree Species upon Ash Production, and Its Properties in Terms of Fusibility

“…8 to 10, it follows that the production of calcium Ca and magnesium Mg due to temperature does not change. Production of potassium (K) exhibited a declining trend, which can be attributed to its evaporation in the processes of thermal decomposition of K2CO3, KCl, K2SO4, and their emission to the atmosphere with the combustion gases (Tissari 2008;Sippula et al 2007). A decrease in the concentration of potassium in ash from wood and bark proportionate to the burning temperature of non-volatile matter had a positive impact upon the stability of the creation of ash in the form of loose matter.…”

Experimental Study of Particle Emissions from a Modern 5 kW Pellet Stove

“…It can be explained by the temperature elevation, which decelerates the condensation and agglomeration process leading to the formation of particles and by enhancing the combustion efficiency with increased burning rate (Sippula et al, 2007) between those regimes as can be seen by decreased carbon monoxide concentrations in the flue gases. Despite significantly lower fuel consumption during part load regimes in tests 6 and 7, the concentrations of emitted particles are close to those of the tests 4 and 5.…”