Short-lived Climate Pollutants - Instituto Nacional de Ecología y

Encuentro Nacional de Respuestas al Cambio Climático:
Calidad del Aire, Mitigación y Adaptación
Cd. de México, junio 27 a julio 1, 2016
Factores de emisión de
contaminantes climáticos de vida corta
Emissions Factors of
Short-lived Climate Pollutants
Luisa T. Molina and the SLCF Project Team
Outline
 Short-lived Climate Pollutants
– Sources of Black carbon
– Sources of Methane
 Characterization of SLCPs in Mexico
– Transport
– Livestock
– Cookstoves
– Brick Production
– Wastewater Treatment
– Landfill
– Oil/Gas
What are Short-Lived Climate Pollutants?
Black carbon (BC)
Tropospheric ozone (O3)
Methane (CH4)
Hydrofluorocarbons (HFCs)
• Relatively short-lived in the atmosphere
• Act as air pollutants (except HFCs)
• Contribute to global and regional climate change
• Multiple benefits of reducing SLCPs:
o Reduce air pollution - Protect public health and crops
o Slow down near-term global warming, reduce regional
impacts of climate change
Sources of Black Carbon
 Black carbon (BC) is a major component of soot; it is produced from
the incomplete combustion of fossil fuels, biofuels, and biomass.
 It is emitted directly into the atmosphere in the form of fine particles.
 Primary sources of BC include diesel engines, small industrial sources,
solid biofuels for cooking & heating, agricultural and forest fires.
25%
7%
10%
of global
BC emissions
50%
Some 60% of the total BC emissions is amenable to control
Sources of CH4 emissions
Agriculture
Municipal waste
Landfill
Fossil fuel extraction & production
Pipeline leakage
Fugitive methane emissions from shale
gas
Rice paddy
Wastewater treatment
Black carbon emissions (Gg) by sources in
2013 for Mexico
Total BC emissions =125 Gg
[Source: INEGEI, 2013]
Methane emissions (Gg) by sources in 2013
for Mexico
Total methane emissions = 4,500 Gg
[Source: INEGEI, 2013]
Pilot Project on Short-Lived
Climate Pollutants in Mexico
Characterization of methane, black carbon and
co-pollutants from key emissions sources
SLCFs-Mexico 2013
Sectors and measurement locations
MONTERREY
L  Landfills
W  Wastewater
LS  Livestock
OG Oil and gas
GUANAJUATO
QUERETARO
M  Mobile
VERACRUZ
MICHOACAN
CS Cook stoves
BK Brick kilns
MEXICO
FEDERAL
DISTRICT
Transport (On-Road and Off-Road)
Participants:
Molina Center for Energy and Environment (MCE2)
Aerodyne Research Inc. (ARI)
Universidad Nacional Autónoma de México (UNAM-CCA)
Tecnológico de Monterrey campus Toluca (ITESM-Toluca)
Ambientalis
California Air Resources Board (CARB)
Instituto Nacional de Ecología y Cambio Climático (INECC)
Secretaría del Medio Ambiente del Distrito Federal (SEDEMA)
RTP, METROBUS, COCA COLA-FEMSA, TURIBUS
Planta de Asfalto del DF
Secretaría de Obras y Servicios del DF
GeoConstruccion
Sistema Maíz
Characterization of Emissions from Key Sources
Aerodyne Mobile Lab
SLCF Mexico-2013
 Complementary measurements –
Mexican universities and research institutions, government
officials and NGOs
SLCFs-Mexico: Transport Sector
Chasing diesel trucks at the RTP Modulo 23
What vehicles we measured?
 17 buses, 16 commercial trucks,
102 Metrobuses (March 2013).
 EPA98, EPA03, EPA04, EURO3-5,
HYBRID.
SLCFs-Mexico
How we measured?
Chasing on-site
Remote Sensing
Emissions ratios were
obtained by correlating
the sampled exhaust
plume (gaseous or
particle) signals with
above background CO2,
which acts as a
combustion tracer.
Chasing Metrobuses
Stationary Sampling
On-board measurements
SLCFs-Mexico
HDDT Emissions Factors
Measurement of BC emissions from off-road vehicles
Site A
Site B
Testing
area
Testing
areas
Installation
area
ECOSTAR
From ITESM
CO, CO2, NO, NO2
Installation
area
AVL Micro-Soot Sensor
From CARB
BC in PM
AXION R/S
From UNAM
CO, CO2, NOX, PM10
Measurement of BC emissions from off-road vehicles
Baseline vs filtered emissions
EXCAVATOR
Selected vehicles included
backhoes, tractor, crane, hammer,
front loaders, bulldozers,
compressor, and power generators,
representing an important variety of
heavy- and medium-duty diesel offroad vehicles.
-3
6
100
-2
0.2
10
x10
x10
-3
20
Baseline
With filter
2
-3
60 6
-3
-3
20
10
4
2
-4
10
4
60
1
4
10
4
20.1
0
0
CO2
10
2
80
20
0
0.2
4
0.1
40
2
10
100
x10
x10
[g/s]
4
Baseline
Baseline
WithDPF
filter
With
4
80
CO
2
NO2
2
-5
0.0 40
10
NO
BC
20
0.1
4
Significant BC reductions were observed when using Diesel Particle Filters
2
0
0
0
0.0
0.01
Summary: Results from Transport Sector
 Black carbon emission factors for public transport buses are higher
than for metrobuses and service diesel trucks. Substantial
differences were present depending on the driving modes.
 Turibuses presented the smaller BC and OC emission factors. High
BC emitters were also high OC emitters in all driving conditions.
 Gaseous species presented a different emissions distribution
compared to PM distributions. Average NOx emission ratios were
similar among the sampled vehicles and had small variability.
 Metrobuses present predominantly emission factors in bi-modal
(acceleration and cruising) driving conditions. This has implications
for the design and evaluation of emissions inventories for these
sources.
 A new database of emission factors for on-road and off-road vehicles
is available, however, more studies are needed.
Livestock Enteric Fermentation
Participants
Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma del
Estado de México
Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de
Yucatán
FMVZ-Universidad Nacional Autónoma de México, Veracruz
Molina Center for Energy and Environment (MCE2)
Aerodyne Research Inc. (ARI)
Methane is produced in the rumen from the fermentation
of forages by the action of rumen anaerobic microbes
A diet rich in forages
resulting in higher
CH4 production.
Low quality forages
also increase CH4
production
The rumen is the fermentation chamber of
ruminants and 95% of all CH4 is produced here
In vivo Measurements of Methane Emissions
Climate zones in Mexico
Tropical,
Humid warm
Warm
semi-humid
Yucatán
(2)
Veracruz
(1)
Toluca (5)
Temperate
sub-humid
Two methodologies:
- AML at UNAM in Martínez de la Torre, Veracruz and UAEM, Toluca in 2013
- Respiration chamber at UADY and UAEM
Dual tracer release experiments AML
First measurement of enteric methane emission from cattle in Mexico
Expt at Faculty of Veterinary Medicine-UNAM in Martinez de la Torre, Veracruz
Tropical climate region (Feb 16-17, 2013)
Dual purpose cattle
Expt at Faculty of Veterinary Medicine-UAEM, Toluca
Temperate climate region (March 4-5, 2013)
Beef cattle
Tracer Ratio Emission Method
Known release rates of tracer compounds spatially separated are
measured after atmospheric advection.
The ratio of methane to tracer measured downwind is used to infer
the methane release rate.
CH4 emission rate is given by Qm = Qt ΔCm/ΔCt
Qm =
CH4 emission rate
Qt =
SF6 release rate
ΔCm =
measured CH4 mixing ratio above background
ΔCt = measured SF6 mixing ratio above background
Ref: Lamb et al., ES&T (1995)
Generation of in vivo methane emission factors
using respiration chambers
In an open-circuit respiration chamber, external air is allowed into the
chamber where it is mixed with the gases exhaled by the animal. The
mixture is drawn by means of a pump through an outlet towards the gas
analyzer where they are quantitatively measured.
Respiration Chamber built in Yucatán for
in vivo measurements
A Nellore (Bos indicus) bull inside a respiration chamber fed a tropical grass and
equipment for measuring methane (Faculty of Veterinary Medicine and Animal Science,
University of Yucatan)
Effect of different secondary metabolites (tannins, saponins, oils) with potential
to reduce enteric methane production were tested with cattle in vivo.
Livestock, environment and renewable energy sources
laboratory at UAEM.
 One head-box type respiration chamber
Methane emissions for high yielding dairy cows and dual
purpose cows measured by different methods
Experimental
site
Measurement
method
Breed
Tropical cattle. Faculty of
Veterinary Medicine UADY
Mérida, Yucatán
Open-circuit
respiration chamber
Dual purpose
Tropical cattle. Faculty of
Veterinary Medicine UNAM
Martínez de la
Torre, Veracruz
Dual tracer release
flux method
Dual purpose
Temperate climate cattle.
Faculty of Veterinary Medicine
UAEM
Toluca, México
Open-circuit
respiration chamber
of the head box type
Holstein
Temperate climate cattle.
Faculty of Veterinary Medicine
UAEM
Toluca, México
Dual tracer release
flux method
Holstein
Experiment
Enteric methane emission by cattle and sheep were measured for the first time in
Mexico using two different methods. The results compare reasonably well.
o Higher emissions were registered by high yielding Holstein cows in Toluca because their
diet is of better quality than in the tropical climate regions. High yielding cows produce less
methane per unit of product than the cows in the tropical climate regions.
Wood-Burning Cookstoves
Participants
Aerodyne Research Inc. (ARI)
Molina Center (MCE2)
UNAM-CCA
UNAM-Morelia
GIRA
Stove Performance Evaluation
Standard Testing Protocol
•
The Water Boiling Test (WBT)
– The WBT is intended to measure stove performance under
standardized laboratory conditions:
– The goal is to compare stoves performing a standard task, to see
which can most effectively combust the fuel and transfer the heat
into the cooking vessel.
– Standard task: boiling water
•
Controlled Cooking Test (CCT)
– Comparison of the stove to the traditional cooking method as
used by local cooks preparing common meals.
Collecting all emissions released in order to determine the
most fuel efficient and cleanest-burning stove design
List of
Cookstoves
Studied by AML
Measurement Site: Patzcuara,
Michoacan, GIRA
Patsari metálica
Ecostufa
Ludeé Biché
Patsari
La mera mera
Onil
Ecocina
Comal-tortilla
Measurements using Compact Dilution Stack
Sampler (UNAM-CCA)
Measurement Site: Improved Cookstove
Laboratory, UNAM, Campus Morelia
Emission ratios for PM composition from the
cookstoves sampled from the AML
Emission ratios for the cook stoves sampled from the AML for PM composition
during the “cold start” (CS) and “simmer test” (ST) sampling periods of the WBT.
Emission ratios for methane and other compounds
from the cookstoves sampled using AML
Emission ratios for the cookstoves sampled during the 2013 intensive field campaign for SO2,
NOX, CH4, C2H6, C2H2, and N2O during the “cold start” (CS) and “simmer test” (ST) periods.
Brick Production
Participants
Molina Center for Energy and Environment (MCE2)
Aerodyne Research Inc. (ARI)
Instituto Nacional de Ecología y Cambio Climático (INECC)
Universidad Nacional Autónoma de México (UNAM)
Universidad Autonóma Metropolitana (UAM-I)
Gamatek (GT)
Instituto de Ecología del Estado de Guanajuato (IEEG)
Desert Research Institute (DRI)
Brick producers (El Refugio and Abasolo)
Brick kilns measurement locations
El Refugio, León, Guanajuato
Abasolo, Guanajuato
Brick kilns characteristics
Brick kiln
MK2 El Refugio
Fuels
Fuels Burning Produced
bricks
(kg)
(hr)
Tons of
cooked
bricks
Pine, Indian Laurel,
Poplar, Eucalyptus,
Pirul, Ficus, Ash tree,
Mesquite, Manure
2430
Poplar, Eucalyptus,
Pirul, Ficus, Ash tree,
Mesquite, Manure
4230
20.5
9727
38.4
7710
3.8
21765
65.9
17.6
4989
20.5
TRAD1 El Refugio
TRAD2 Abasolo
Avocado, Diesel,
Sawdust
Pollutants








CH4
BC
NOx
VOCs
CO
CO2
N2O
SO2
Brick kiln emissions measurements
DOWNWIND
 High-time resolution (~1 sec)
gaseous and PM measurements.
 Emission rates were obtained using
the tracer method by continuously
locating the AML downwind of the
plume and using a controlled tracer
emission rate.
 Measurements included PM2.5 mass
with quartz filters that were
analyzed for inorganics, elemental
and organic carbon using thermooptical methods.
 Additional measurements included
temperature, wood consumption,
fuel’s carbon content, and brick’s
quality.
AT THE SOURCE
Qtz filterQsampler
Tracer release
point
Ethyl Acetate tracer
Summary: Results from brick Productions
 The MK2 was cleaner on average than the traditional kiln but only subtly
indicating the cover and filter on the MK2 is useful but other factors may
be more important.
 The fixed traditional kiln had the highest BC emission ratios but also
lastest the shortest 3 hours vs 20 hours.
 The results have revealed a complex evolution of emission factors for the
brick production process. Observed black carbon emissions ratios are
highly correlated with furnace temperature, whereas organic composition
is correlated with the kiln’s temperature.
 Energy consumption is an important parameter for determining the
efficiency of the kiln. However analysis of trade-offs between burning
time duration and overall emissions are needed to taken into account for
assessing the performance of the kiln.
 Time evolution of emission factors is kiln dependent , during what part of
process and for what length of time does a kiln emit more.
 Need to create a bigger dataset (more kilns).
Landfills
Participants
Aerodyne Research Inc. (ARI)
Molina Center for Energy and Environment (MCE2)
Instituto Nacional de Ecología y Cambio Climático (INECC)
Bioeléctrica de Nuevo León (BENLESA)
Secretaria de Obras y Servicios del CDMX
Measuring Sites for Landfills
BENLESA
Nuevo Leon
Bordo Poniente
Mexico City
1.8 km
2.2 km
 Has methane capture
technology at different locations
depending on age and
composition
 Operated since 1985, the landfill
was already in closure process
(not trash disposed), but included
a trash separation facility
Measuring Emissions from Landfills
 The methane and selected VOCs emissions from the landfills were
measured using the “tracer ratio emission method”
Methane Emissions
from BENLESA
Landfills
Methane
is being
captured
Methane is
not being
captured
Active biogas collection zone
exhibited much lower apparent
emissions of methane than the
uncontrolled landfill sector.
Wastewater Treatment Plants
Participants
UNAM Instituto de Ingeniería
Aerodyne Research Inc.
Molina Center for Energy and the Environment
Municipal Wastewater Treatment facilities hosting the measurement sites
Wastewater treatment (WWT) can produce methane if it is degraded
anaerobically. The extent of CH4 production depends primarily on the
quantity of degradable organic material in the wastewater, the
temperature, and the type of treatment system.
Distribution of WWTP by region and technologies
15 facilities from three regions (north, central and
south) were selected to account for the wide ranges of
temperature in the country.
Three different treatment technologies
Activated sludge with anaerobic digestion
Up-flow Anaerobic Sludge Blanket reactor
Stabilization ponds
Stabilization Ponds
Activated sludge with anaerobic digestion
Summary of CH4 conversion and emission factors by
operation practices
Wastewater treatment process
Activated sludge with anaerobic
digestion
CH4 conversion factor* (m3/kg VSrem)
“Best practices”
“Poor operation”
0.46 ± 0.03
0.19 ± 0.02
CH4 emission factor (kg/kg BODrem)
“Best practices”
“Poor operation”
Stabilization ponds
0.45 ± 0.13
0.66 ± 0.115
CH4 emissions factor (m3/kg CODrem)
UASB
“Best practices”
0.24 ± 0.011
“Poor operation”
0.39 ± 0.06
Summary: WWTP Methane Emissions
 CH4 emissions from wastewater treatment varies among regions,
depending on the environmental and operating conditions. Thus, specific
emission factors could be considered as indicators of differences in
treatment systems between each region.
 The theoretical values of CH4 emissions from anaerobic wastewater
treatment process using the IPCC methodology present an overestimation
compared to actual CH4 emissions obtained in the field.
 The results allow us to reach level 3 of the IPCC methodology, estimating
our own emission factors for the main systems of WWT in Mexico.
 In the specific case of activated sludge with anaerobic digestion process, it
will be important to measure CH4 on the mono-landfills used for the disposal
of sewage sludge. Currently, there are no data regarding methane
emissions from these sites.
 For stabilization ponds, it is very important measure CH4 emissions
throughout the year in order to describe the temporal and seasonal
variability present.
Oil and Gas
Participants
Molina Center for Energy and Environment (MCE2)
Aerodyne Research Inc. (ARI)
Instituto Nacional de Ecología y Cambio Climático (INECC)
Instituto Mexicano del Petróleo (IMP)
Petroleos Mexicanos (PEMEX)
Measuring Emissions from oil and gas facilities
 Three oil and gas
facilities (Tajin 2&4,
Tajin 5, and Punta de
Piedra using the tracer
release method.
 These are “baterias”,
separating the incoming
crude oil and gas.
 Quantified methane
emissions from direct
leaks are reported.
Summary of results from oil-gas measurements
 The AML measured individual plumes from gas leaks and flares from
the oil and gas facilities and emissions were estimated using the
tracer-release method.
 The variability of the emissions rates estimated from the three sites
(Tajin 2, Tajin 5 and Punta de Piedra) demonstrates the importance of
local-based measurements in building up accurate inventories from oil
and gas facilities.
 An estimated BC average emission rate of 0.48 g/kg of fuel
(equivalent to 0.32 g/m3 gas flared at STP) was obtained at the Punta
de Piedra site.
Summary: SLCPs Emissions Characterization
 Database of emission factors for several key emissions sectors have been
measured using different methodologies.
 The selection of sampling sites was guided by information about the
emissions, the types of technology used at the sites, as well as security
and accessibility to infrastructure and services.
 In most sectors, the emissions factors were obtained for the first time in
Mexico. e.g.,
– enteric methane emission by livestock were measured for the first time
in Mexico using two different methods in 2 different climate zones;
– WWTP emissions factors were obtained for 3 different technologies;
– EFs differed from those used previously for inventories calculation.
 The variability of the emissions factors estimated demonstrates the
importance of local-based measurements.
– Substantial variability in management and operating conditions
 A larger database is needed in building up accurate inventories.
Acknowledgements
 Financial support
Global Environmental Facility, UNEP, INECC, USAID, MCE2
 SLCF-Project Participants
MCE2, INECC, ARI, UNAM-CCA, UNAM-II, UAEM, UADY,
UNAM-Morelia, GIRA, TEC-Toluca, CARB, UAM-I, Gamatek,
IMP
 Many collaborators, including:
SEDEMA, Secretaría de Obras y Servicios del DF, RTP, Metrobus,
Coca-Cola Femsa, Bioeléctrica de Nuevo León (BENLESA), Planta de
Asfalto del DF, GeoConstruccion, Sistema Maíz, Instituto de Ecología del
Estado de Guanajuato (IEEG), DRI, Brick producers (El Refugio and
Abasolo), PEMEX, EcoZoom, Eco-Estufa, Helps International, Municipal
wastewater treatment plants from many states
THANK YOU!
¡GRACIAS!