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Title: Reducing ultrafine particle emissions using air injection in wood-burning cookstoves

Abstract

In order to address the health risks and climate impacts associated with pollution from cooking on biomass fires, researchers have focused on designing new cookstoves that improve cooking performance and reduce harmful emissions, specifically particulate matter (PM). One method for improving cooking performance and reducing emissions is using air injection to increase turbulence of unburned gases in the combustion zone. Although air injection reduces total PM mass emissions, the effect on PM size-distribution and number concentration has not been thoroughly investigated. Using two new wood-burning cookstove designs from Lawrence Berkeley National Laboratory, this research explores the effect of air injection on cooking performance, PM and gaseous emissions, and PM size distribution and number concentration. Both cookstoves were created using the Berkeley-Darfur Stove as the base platform to isolate the effects of air injection. The thermal performance, gaseous emissions, PM mass emissions, and particle concentrations (ranging from 5 nm to 10 μm in diameter) of the cookstoves were measured during multiple high-power cooking tests. Finally, the results indicate that air injection improves cookstove performance and reduces total PM mass but increases total ultrafine (less than 100 nm in diameter) PM concentration over the course of high-power cooking.

Authors:
 [1];  [2];  [2];  [2]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1342536
Report Number(s):
LBNL-1006082
Journal ID: ISSN 0013-936X; ir:1006082
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Environmental Science and Technology
Additional Journal Information:
Journal Volume: 50; Journal Issue: 15; Journal ID: ISSN 0013-936X
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES

Citation Formats

Rapp, Vi H., Caubel, Julien J., Wilson, Daniel L., and Gadgil, Ashok J. Reducing ultrafine particle emissions using air injection in wood-burning cookstoves. United States: N. p., 2016. Web. doi:10.1021/acs.est.6b01333.
Rapp, Vi H., Caubel, Julien J., Wilson, Daniel L., & Gadgil, Ashok J. Reducing ultrafine particle emissions using air injection in wood-burning cookstoves. United States. doi:10.1021/acs.est.6b01333.
Rapp, Vi H., Caubel, Julien J., Wilson, Daniel L., and Gadgil, Ashok J. 2016. "Reducing ultrafine particle emissions using air injection in wood-burning cookstoves". United States. doi:10.1021/acs.est.6b01333. https://www.osti.gov/servlets/purl/1342536.
@article{osti_1342536,
title = {Reducing ultrafine particle emissions using air injection in wood-burning cookstoves},
author = {Rapp, Vi H. and Caubel, Julien J. and Wilson, Daniel L. and Gadgil, Ashok J.},
abstractNote = {In order to address the health risks and climate impacts associated with pollution from cooking on biomass fires, researchers have focused on designing new cookstoves that improve cooking performance and reduce harmful emissions, specifically particulate matter (PM). One method for improving cooking performance and reducing emissions is using air injection to increase turbulence of unburned gases in the combustion zone. Although air injection reduces total PM mass emissions, the effect on PM size-distribution and number concentration has not been thoroughly investigated. Using two new wood-burning cookstove designs from Lawrence Berkeley National Laboratory, this research explores the effect of air injection on cooking performance, PM and gaseous emissions, and PM size distribution and number concentration. Both cookstoves were created using the Berkeley-Darfur Stove as the base platform to isolate the effects of air injection. The thermal performance, gaseous emissions, PM mass emissions, and particle concentrations (ranging from 5 nm to 10 μm in diameter) of the cookstoves were measured during multiple high-power cooking tests. Finally, the results indicate that air injection improves cookstove performance and reduces total PM mass but increases total ultrafine (less than 100 nm in diameter) PM concentration over the course of high-power cooking.},
doi = {10.1021/acs.est.6b01333},
journal = {Environmental Science and Technology},
number = 15,
volume = 50,
place = {United States},
year = 2016,
month = 6
}

Journal Article:
Free Publicly Available Full Text
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  • Aldehyde emissions from wood-burning fireplaces were measured. Total aldehydes ranged from 0.6 to 2.3 g/kg of wood burned based on tests with cedar, jack pine, red oak, and ash. Formaldehyde, acetaldehyde, and p-tolualdehyde were the major aldehydes emitted with formaldehyde comprising 21-42% of the total. Aldehyde and particle emissions were inversely correlated with burn rate and may also be related to wood type. On the basis of our measurements, nationwide aldehyde emissions from residental wood burning were estimated to be between 14 and 54 Gg/year. This value is comparable to both power plant and automobile aldehyde emission sources. It ismore » likely that residental wood burning is a major source of primary aldehydes during the winter. 20 references.« less
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  • Emissions from a small residential wood stove and a newly developed residential stove burning charcoal have been characterized by chemical analysis and mutagenicity testing (Ames Salmonella test). For wood burning the samples were taken under normal and starved air conditions burning birch and spruce separately. The burning conditions in the stove seemed to influence the emissions to a larger extent than the type of wood. The emissions of aldehydes, benzene and polycyclic aromatic hydrocarbons from the charcoal-burning stove are lower by a factor of 25-1000 as compared to the wood stove. The mutagenicity of the emissions showed a similar trend.