Black carbon, organic carbon, and co-pollutant emissions and energy efficiency from artisanal brick production in Mexico

Miguel Zavala,Edward C Fortner,Judith C Chow,Beatriz Cardenas,Joseph R Roscioli,Israel Monsivais,Luisa T Molina,Walter B Knighton,Jose Luis Munguia,Pablo Maiz,Charles E Kolb,Scott C Herndon,John G Watson

doi:10.5194/acp-18-6023-2018

Abstract

Abstract. In many parts of the developing world and economies in transition, small-scale traditional brick kilns are a notorious source of urban air pollution. Many are both energy inefficient and burn highly polluting fuels that emit significant levels of black carbon (BC), organic carbon (OC) and other atmospheric pollutants into local communities, resulting in severe health and environmental impacts. However, only a very limited number of studies are available on the emission characteristics of brick kilns; thus, there is a need to characterize their gaseous and particulate matter (PM) emission factors to better assess their overall contribution to emissions inventories and to quantify their ecological, human health, and climate impacts. In this study, the fuel-, energy-, and brick-based emissions factors and time-based emission ratios of BC, OC, inorganic PM components, CO, SO2, CH4, NOx, and selected volatile organic compounds (VOCs) from three artisanal brick kilns with different designs in Mexico were quantified using the tracer ratio sampling technique. Simultaneous measurements of PM components, CO, and CO2 were also obtained using a sampling probe technique. Additional measurements included the internal temperature of the brick kilns, mechanical resistance of bricks produced, and characteristics of fuels employed. Average fuel-based BC emission factors ranged from 0.15 to 0.58 g (kg fuel)−1, whereas BC∕OC mass ratios ranged from 0.9 to 5.2, depending on the kiln type. The results show that both techniques capture similar temporal profiles of the brick kiln emissions and produce comparable emission factors. A more integrated inter-comparison of the brick kilns' performances was obtained by simultaneously assessing emissions factors, energy efficiency, fuel consumption, and the quality of the bricks produced.

Highlights

Artisanal clay brick production using small-scale traditional kilns is a highly polluting activity occurring in developing countries and economies in transition to manufacture building materials
The lower variability of the fuelbased emission factors compared to emission rates indicates that the normalization of the emissions of combustion byproducts effectively takes into account the variations in the thermal energy employed in the cooking process
Since estimations of the integrated emissions burden using emission rates depend on the total brick production time, emission rates are not a good indicator to compare the environmental performance of the kilns

Summary

Introduction

Artisanal clay brick production using small-scale traditional kilns is a highly polluting activity occurring in developing countries and economies in transition to manufacture building materials. Traditional brick production is a serious local health hazard to the residents of the poor neighborhoods that typically host brickyards, as well as to brickmakers themselves. M. Zavala et al.: Emissions from artisanal brick production in Mexico port, and education infrastructure. Brick producers often sell the bricks to intermediaries and the economic revenue for producers can be marginal. These conditions contribute to the perpetuation of severe environmental and social injustice problems

Methods

Results

Conclusion