Ozgen S.,Polytechnic of Milan |
Caserini S.,Polytechnic of Milan |
Galante S.,Polytechnic of Milan |
Giugliano M.,Polytechnic of Milan |
And 5 more authors.
Atmospheric Environment | Year: 2014
Four manually fed (6-11kW) firewood burning and two automatic wood pellets (8.8-25kW) residential heating appliances were tested under real-world operating conditions in order to determine emission factors (EFs) of macropollutants, i.e., carbon monoxide (CO), nitrogen oxides (NOx), non-methane hydrocarbons (NMHC), particulate matter (PM) and trace pollutants such as polycyclic aromatic hydrocarbons (PAH) and dioxins. The results were examined for the influence of different factors (i.e., type of wood, appliance and combustion cycle). The experimental EFs were also compared with the values proposed by the European emission inventory guidebook used in the local inventory in order to evaluate their representativeness of real world emissions. The composite macropollutant EFs for manually fed appliances were: for CO 5858gGJ-1, for NOx 122gGJ-1, NMHC 542gGJ-1, PM 254gGJ-1, whereas emissions were much lower for automatic pellets appliances: CO 219gGJ-1, for NOx 66gGJ-1, NMHC 5gGJ-1, PM 85gGJ-1. The highest emissions were generally observed for the open fireplace, however traditional and advanced stoves have the highest overall CO EFs. Especially for the advanced stove real-world emissions are far worse than those measured under cycles used for type testing of residential solid fuel appliances. No great difference is observed for different firewood types in batch working appliances, diversely the quality of the pellets is observed to influence directly the emission performance of the automatic appliances. Benzo(b)fluoranthene is the PAH with the highest contribution (110mgGJ-1 for manual appliances and 2mgGJ-1 for automatic devices) followed by benzo(a)pyrene (77mgGJ-1 for manual appliances and 0.8mgGJ-1 for automatic devices). © 2014 Elsevier Ltd.
Migliavacca G.,INNOVHUB Stazione Sperimentale per i combustibili |
Morreale C.,INNOVHUB Stazione Sperimentale per i combustibili |
Hugony F.,INNOVHUB Stazione Sperimentale per i combustibili |
Tombolato I.,Agenzia Regionale per la Protezione dellAmbiente della Valle dAosta |
Pession G.,Agenzia Regionale per la Protezione dellAmbiente della Valle dAosta
Chemical Engineering Transactions | Year: 2014
Particulate Matter (PM) emissions from small scale appliances burning wood fuels used for domestic heating is one of the major environmental issues in many European areas. Biomass combustion leads to the presence of high concentrations of PM10 measured in ambient air, especially during the winter season and in those areas where wood stoves and fireplaces are the main heating systems. In this study the efficiency of PM abatement of small scale electrostatic precipitator (ESP) are measured and compared for different appliances. In particular two different commercial systems specifically developed for domestic stoves have been tested in connection with different kinds of appliances; the two devices differ from their electrode length. Particle emissions were measured upstream and downstream of the ESPs to evaluate the efficiency of the devices. Both the devices have been used in connection with an 8 kW pellet stove and a 25 kW pellet boiler; the ESP with shorter electrode has been tested also with an advanced wood stove. Beech wood logs and a low quality pellet have been used in the tests. The gas composition of the fumes have been determined at the exit of the appliances in order to estimate the combustion performances of the stoves and boiler, in particular the amount of oxygen (O2), carbon monoxide (CO), carbon dioxide (CO2), nonmethanic gas phase hydrocarbon (VOC-NMet) have been measured. ESPs are specifically devoted to reduce particulate matter concentration in gas streams and their efficiency is dependant on particle resistivity and then it may change with the composition of the particle emitted. Another factor that can affect the efficiency of ESP is the level of fouling of the active surfaces and hence the aging of the precipitator may strongly reduce the abatement. These effects have been studied in the present work by measuring the mass concentration of total particulate matter and the total number concentration (TNC) of nanoparticles (with an aerodynamic diameter between 5.6 and 560 nm) in the different appliances with different fuels and under different operating conditions; in particular aging tests have been carried out to simulate the typical usage in a domestic installation. The test results show a good rate of abatement both on PM and nanoparticles for both the ESPs and in all conditions when the filters are clean, while a progressive reduction in the efficiency is observed after a long term use mainly in the smaller device where the active surfaces are lower. Copyright © 2014,AIDIC Servizi S.r.l.