AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Combustion Emissions from Biomass Cookstoves vs. Operational Firepower: Lab and Field Observations
KELSEY BILSBACK, Kelley Hixson, Michael Johnson, Jack Kodros, James Liacos, Eric Lipsky, Christian L'Orange, Jeffrey R. Pierce, Brooke Reynolds, Allen Robinson, R. Subramanian, John Volckens, Colorado State University
Abstract Number: 437 Working Group: Combustion
Abstract Solid fuel combustion in cookstoves is known to have negative effects on air quality, climate, and human health as a result of the emission of incomplete combustion products. Because stoichiometry, temperature, and mixing dynamics may have considerable local variations within a cookstove, the emissions rates are unsteady and difficult to quantify. The temporal variabilities in emissions are typically not accounted for because of restrictive laboratory testing practices and the fact that typical testing procedures rely heavily on integrated measurements. In the current study, a laboratory protocol was developed that varied firepower, a proxy for cookstove operation, to quantify how emissions characteristics and quantities vary due to changes in cookstove combustion parameters. To represent typical field combinations, approximately fifteen different stove types and seven different fuel types (24 stove/fuel combinations) were tested. An extensive suite of real-time and integrated aerosol instrumentation was used during the study to characterize the fresh cookstove aerosols. Modified combustion efficiency and firepower were calculated using gas measurements from a 5-Gas Analyzer (CO2, CO), and particle characteristics were quantified using gravimetric measurements, a transmissometer and a Photoacoustic Exinctiometer. Emissions rates were parameterized using cookstove combustion variables to understand how the characteristics of biomass combustion influence emissions. The results of the tests demonstrate that firepower can describe a significant amount of variance in black carbon emissions (Spearmen correlation between 0.35-0.96) and total particulate matter emissions (Spearmen correlation between 0.32-0.85). Finally, during two field campaigns, in Honduras and China, the characteristics of uncontrolled cookstove emissions were monitored using similar instrumentation. Preliminary results from the field tests indicate that firepower can explain a considerable amount of emissions variation under field conditions. Initial validation of the laboratory parameterizations with data from the field campaigns shows promise.