Determining seasonal greenhouse gas emissions from ground-level area sources in a dairy operation in central Texas.

Greenhouse gas (GHG) emissions from agricultural production operations are recognized as an important air quality issue. A new technique following the U.S.

Particulate matter emission factors for almond harvest as a function of harvester speed.

Almond harvest accounts for substantial particulate matter less than 10 microm in aerodynamic diameter (PM10) emissions in California each harvest season. This paper addresses the reduction of harvester ground speed from a standard 8 km/hr (5 mph) to 4 km/hr (2.5 mph) as a possible mitigation measure for reducing PM10 emissions.

Seasonal ammonia emissions from a free-stall dairy in central Texas.

Studies show that agricultural and animal feeding operations (AFOs) contribute a considerable amount of ammonia (NH3) to the atmosphere. Agricultural NH3 emissions are recognized as an important air quality issue. Biological decomposition of manure from dairy operations results in emissions of NH3 and other gases.

Seasonal and spatial variations of ammonia emissions from an open-lot dairy operation.

There is a need for a robust and accurate technique to measure ammonia (NH3) emissions from animal feeding operations (AFOs) to obtain emission inventories and to develop abatement strategies. Two consecutive seasonal studies were conducted to measure NH3 emissions from an open-lot dairy in central Texas in July and December of 2005. Data including NH3 concentrations were collected and NH3 emission fluxes (EFls), emission rates (ERs), and emission factors (EFs) were calculated for the open-lot dairy.

Theoretical study of the impact of particulate matter gravitational settling on ambient coarse particulate matter monitoring for agricultural emissions.

The particle size distributions (PSDs) of particulate matter (PM) in the downwind plume from simulated sources of a cotton gin were analyzed to determine the impact of PM settling on PM monitoring. The PSD of PM in a plume varies as a function of gravitational settling. Gravitational settling has a greater impact on the downwind PSD from sources with PSDs having larger mass median diameters (MMDs).

The recovery of ammonia and hydrogen sulfide from ground-level area sources using dynamic isolation flux chambers: bench-scale studies.

Controlled bench-scale laboratory experiments were conducted to evaluate the recovery of ammonia (NH3) and hydrogen sulfide (H2S) from dynamic isolation flux chambers. H2S (80-4000 ppb) and NH3 (5000-40,000 ppb) samples were diffused through the flux chamber to simulate ground level area source emissions while measuring the inlet and outlet flux chamber concentrations simultaneously. Results showed that the recovery of H2S during a 30-min sampling time was almost complete for concentrations >2000 ppb.