Waltech Systems

Advancing Field Measurements of Particle Emissions from Coal and Biomass Brick Kilns

Mountain Air

Ryan Thompson (ryan@mtnaireng.com)

Karl Walter

Tami Bond, Cheryl Weyant, Emily Floess, Paul Francisco, Zach Merrin

Ellen Baum Sameer Maithel, Sonal Kumar, Ananthakrishnan Ravi

Sujan Shrestha, Prakash Bhave, Praveen Puppala, Bidya Padhan

Santosh Guatam Sagar Adhikari

Santosh Bhaskar, Uma Rajarathnam Fabio Andres Salgado

Arian Montalvo, Jon Bickel

Introduction Clay bricks are a common building material (over a trillion are produced annually in the world). Most bricks are fired in coal or biomass kilns without pollution control technologies. These kilns are a significant contributor to air pollution in developing regions, but few emission measurements have been conducted. Measurements are needed to understand health and climate impacts, but conventional measurement methods for stationary sources are not adequate for kilns because of: • high particle concentrations • large temporal variability in emissions • low exhaust flows • exclusion of climate relevant emissions such as black

carbon

Equipment: Ratnoze Dilution Sampler

Sampling Method

• For kilns with stacks: isokinetic probe through a port in the stack wall.

• For kilns without stacks, multi-point array probe in the open plume above the kiln.

• The sample is mixed with clean, dry dilution air to reduce particle concentrations and humidity, and to encourage representative partitioning of semi-volatile species.

• Output metrics are calculated using the carbon balance method.

Carbon balance method: • Real-time particle scattering and absorption data is used

to apportion the emissions to specific events, to identify emission patterns, and to show relative changes in PM composition within a sampling period.

Objectives • Develop method and equipment for measuring climate

relevant brick kiln emissions. • Demonstrate method on wide range of kiln types • Build capacity for ongoing measurements in South Asia

and South America • Build emission inventories for brick kilns • Understand kiln emission patterns and causal factors • Evaluate effectiveness of improved kiln technologies

Flow Schematic

Isokinetic Chimney Probe

Measures: • CO • CO2

• SO2

• PM2.5

• BC • OC • Particle Scattering • Particle Absorption • Stack Velocity • Dilution Ratio

Features: • Specialized for solid fuel

combustion emissions • Forced dilution up to 20:1 DR • Real-time measurements • On-board data logger • Wireless transmitter • Isokinetic stack sampling • Open plume sampling • 15 hour battery life • Open source design

Kilns

Brick Initiative

Emission factor (g/MJ)

Emission rate (g/hr)

Diluted emission concentrations

(g/m^3)

Emission factor (g/kg fuel)

MCE

Emission factor (g/kg brick)

Fuel carbon fraction

(kg C/kg fuel) Fuel heating value

(MJ/kg fuel)

Fuel consumption rate

(kg fuel/hr)

Brick production rate

(kg brick/hr)

Carbon emission ratios

(g/kg C)

Measured Inputs Calculated Outputs

Conclusions • Large temporal variability in emissions for kilns fed manually by kiln

workers and also for kilns fed automatically with Carbojets (forced-air coal powder injectors)

• Long sample time (several hours) is required for representative emission factors

• PM emissions depend on many factors such as fuel type, feeding patterns, fraction of internal and external fuel, and kiln technologies

Clamp

Hoffman

Coleman

Artisanal

More Information Equipment documentation: www.mtnaireng.com/Emissions-Equipment/ Brick Kiln Emission Measurement Guidance Document: www.mtnaireng.com/Brick_Kiln_Measurement_Guidelines.pdf Brick Kiln Emission Sampling Procedure: www.mtnaireng.com/Brick_Kiln_Emissions_Sampling_Procedure_v11.pdf

Zig-zag Bull ‘s Trench

Zig-zag

Further Analysis • PM2.5 , EC, and OC emission factors (awaiting filter and fuel analysis) • Investigate sensitivity of output metrics to sample duration • Compare results between carbon balance method and stack flow

(total capture) method for kilns with stacks. • Compare particle emissions between kiln technologies

No Stack:

Natural Draft:

Forced Draft:

Results

Bull’s Trench (India)

ND Zigzag (India)

Bull’s Trench (Nepal)

FD Zigzag (Nepal)

Clamp#1 (India)

Clamp#2 (India)

Forced Draft Zigzag Kiln (Colombia) with Carbojet (forced air coal injector)

Natural Draft Bull’s Trench Kiln (India)

Natural Draft Zigzag Kiln (India)

Kiln exhaust routed through fresh batch of bricks (duct opened, dilution air drawn up stack)

SO2 drops from scrubbing by fresh wet bricks Oscillations from fuel feeding pattern

Coal fuel additions Mustard stalk fuel addition

Change in Stak Temp indicates change in kiln process

Carbojet has unsteady coal feed rate

Tunnel