How bricks are stacked impacts air quality in Bangladesh : Goats and Soda : NPR

Through the dry winter months in Bangladesh, hundreds of staff shovel tens of millions of tons of coal into kilns throughout the nation. As columns of hand-packed bricks bake and harden, darkish plumes of smoke pour out of greater than 8,000 smokestacks that mark the skyline of each rural and concrete areas.

“It is a variety of black smoke, impacting the employees and close by villagers, but in addition the general air high quality of the area,” mentioned Sameer Maithel, an engineer with Greentech Information Options, a consulting agency in Delhi, India.

Bangladesh’s air constantly ranks among the many most polluted on Earth. Brick kilns contribute anyplace from 10 to 40% of the tiny particles that make up that air pollution. These particles can enter our lungs and even our bloodstream, inflicting well being issues, together with respiratory ailments, stroke and even cognitive issues.

However one thing so simple as stacking the bricks a unique approach may put a significant dent in that pollution, based on a brand new research of over 275 kilns printed in Science by Maithel and his colleagues.

“That is fantastic proof of how easy low value interventions can have a big effect on vitality use,” mentioned William Checkley, an epidemiologist at Johns Hopkins College who wasn’t concerned within the research. “If we will implement these, we may have a major affect in vitality use and emissions, bettering air high quality all through southeast Asia.”

The need of brick

Bricks are the primary constructing block for Bangladesh. The densely populated and quickly urbanizing nation produces almost 30 million bricks a yr – greater than 90% from loosely regulated, coal-burning kilns.

“It is fairly easy and cheap to arrange traditional-style brick kilns, in order that they’ve simply proliferated,” mentioned Nina Brooks, a worldwide well being researcher at Boston College.

The method goes one thing like this: First, dun-colored clay bricks are molded with a wood field and stacked within the solar to dry. Subsequent, tons of of hundreds of bricks are stacked within the firing chamber and coated with ash. Then, staff shovel heaps and many coal because the bricks fireplace, firming them up.

“The combustion effectivity of those brick kilns is absolutely low,” mentioned Brooks, which means they find yourself burning much more coal than they should, “Which is why they’re so closely polluting right here.”

Every kiln can make use of as much as 200 staff. They’re essentially the most immediately impacted by the smoke, with one research discovering nearly 80% report some kind of respiratory problems. However they are not the one ones. Kilns are sometimes near densely populated areas, including to the smog that comes from metropolis life.

Brick staff stability stacks of bricks on their heads because the carry them from the kiln close to Dhaka, Bangladesh.

Zakir Hossain Chowdhury/Anadolu Company/Getty Photographs/Anadolu

cover caption

toggle caption

Zakir Hossain Chowdhury/Anadolu Company/Getty Photographs/Anadolu

Whereas there are laws on the place kilns can and may’t function, they are not all the time adopted, mentioned Brooks. “We discovered that 77% of brick kilns are illegally positioned too shut to a college.”

Fashionable, high-tech kilns produce considerably much less air pollution, however they’re as much as 25 instances dearer to construct and function. “They’ve not likely taken off,” mentioned Brooks.

As an alternative, the workforce regarded for options that may be simpler and cheaper for the typical brick producer to undertake.

Easy interventions

In his many years of working with brick kiln house owners in India as a consulting engineer, Maithel has seen questionable practices.

Many kiln operators pack too many bricks within the kiln too tightly, he mentioned. That tight spacing chokes out oxygen circulation, which is required for environment friendly burning. It additionally means scorching coals get caught on the high of the stack as a substitute of falling to the underside, main some bricks to be overbaked and others not fired sufficient.

He is additionally seen that staff typically shovel coal in bouts, working onerous in groups of two or three, after which all taking breaks collectively. That leads to uneven fueling, which may stymie effectivity too.

As an vitality techniques engineer, Maithel knew that a number of easy modifications may actually assist. Merely stacking the bricks in a zig-zag sample that will increase airflow and making certain coal will get delivered extra constantly ought to assist the kilns function extra effectively, he mentioned.”The higher you’ll be able to present gas and air mixing, the likelihood of black smoke will likely be much less.”

To see if such easy interventions may assist scale back air air pollution and increase income, the workforce deliberate an enormous experiment throughout 276 kilns. One group of kiln house owners and staff had been taught the right way to implement these interventions. One other group received the identical coaching plus data on how the modifications would get monetary savings. The management group received no coaching.

Then, throughout firing season within the winter, the researchers measured varied points of kiln efficiency, together with gas use.

So, did it work? 

The outcomes had been promising.

Kilns that adopted these measures noticed vital advantages. On common, gas use dropped by about 23 %, the research discovered. The researchers estimate that would cut back the carbon dioxide and particulate matter popping out of the kilns by about 20%.

“We confirmed that straightforward, low-cost interventions can actually scale back air pollution,” mentioned Mahbubur Rahman, an environmental well being researcher on the International Centre for Diarrhoeal Disease Research, Bangladesh. 

And the modifications improved each employee circumstances and the underside strains for kiln house owners. Over the season, they’d saved near $40,000 every due to diminished gas use, mentioned Brooks. Brick high quality went up as effectively.

In truth, kiln house owners had been so impressed {that a} yr later, people who had adopted the brand new practices had been nonetheless training them.

However to actually make a dent in Bangladesh’s air air pollution, many extra kilns must signal on. The analysis workforce, which incorporates scientists from the U.S., India and Bangladesh, are actually working with the Bangladeshi authorities to increase this coaching.

“It is a hopeful story,” Brooks says, “of a spot the place options are fairly possible.”