在孟加拉国，大多数砖的制造都是在非正式的传统燃煤窑中进行的，这是温室气体排放和空气污染的最大来源之一。 在这里，砖窑工人粉碎煤，这些煤将在制砖过程中用作燃料。 图片来源：Sushanta Kumar Paul。

环境正义

澳门威尼斯人注册网站研究人员开发切实可行的解决方案，以减少排放和改善孟加拉国砖制造业的空气质量

一项新的澳门威尼斯人注册网站研究发现，砖窑业主在接受培训和支持后，愿意实施节能运营变革。 这些变化减少碳排放的社会效益是成本的65比1。

Brick manufacturing is a central component of the economy in South Asia, but also a 主要来源 of greenhouse gas emissions and 空气污染, as the practice releases carbon dioxide (CO₂), fine particulate matter (PM_2.5), and other contaminants into the environment. 这种以煤为动力的行业对低收入和中等收入国家的人类健康、农业和环境构成严重威胁，这些国家缺乏监测和管理这些主要是非正式业务的能力。

As scientists continue to 拉响警报 on the increasing dangers of fossil fuels, a new study by researchers at the 公共卫生学院, Stanford University, 位于, Greentech Knowledge Solutions, and the Bangladesh University of Engineering and Technology has introduced an evidence-based strategy proven to increase energy efficiency and reduce emissions in the brick manufacturing industry by encouraging operational changes that prioritize practicality and profit. 

发表于期刊 科学该澳门威尼斯人注册网站研究分析了一项随机对照试验（RCT）的结果，该结果表明，如果砖窑所有者得到适当的培训和支持，并且这些变化符合他们的盈利动机，他们愿意并能够在没有法律强制执行的情况下，在其运营中实施更清洁、更高效的商业实践。 该澳门威尼斯人注册网站研究是第一个严格证明成功的策略，以提高传统砖窑行业的效率。

该随机试验评估了一项干预措施，该措施在2022-2023年砖窑季期间为孟加拉国276座砖窑的窑主提供教育资源、培训和技术支持。 The intervention aimed to motivate the owners to make energy-efficient adjustments to their manufacturing process, such as streamlining brick stacking and using powered biomass fuel, both of which improve complete fuel combustion and reduce heat loss in the kilns.

The study found that 65 percent of the brick kiln owners adopted these changes, which led to a 23-percent reduction in energy use. The changes substantially improved air quality, contributing to 20-percent reductions in CO₂ and PM_2.5 emissions. 这一干预措施还大大节省了煤炭支出，提高了砖的质量。 Notably, the researchers estimated that the social benefits due CO₂ reductions from the intervention outweighed costs by a factor of 65 to 1 and that the CO2 reductions were achieved at the low cost of $2.85/ton. 第二年，当澳门威尼斯人注册网站研究小组再次回到参与的砖窑时，他们发现改进的做法不仅得到了持续的采用，而且得到了更多的采用。

“Brick manufacturing is central to development, urbanization, and construction in Bangladesh and across South Asia, but the industry has not experienced much innovation, leaving open the possibility for win-win solutions that target low efficiency,” says study lead and corresponding author 尼娜布鲁克斯, assistant professor of global health. “我们的澳门威尼斯人注册网站研究结果表明，砖窑业主愿意接受简单的改变，保护人类和环境健康，当他们有知识和培训，这些变化带来切实的经济收益。”

These findings are promising, as previous efforts to regulate the brick kiln industry have been unsuccessful in Bangladesh, where workers produce 270亿块砖 annually in harsh working conditions. This industry 账户 for 17 percent of CO₂ emissions and 11 percent of PM_2.5 emissions each year. Existing 规定, such as fuel mandates that ban the use of firewood, or laws that require brick kilns to be distanced from 学校, health facilities, and other establishments, are only 最低限度执行; for example, the majority of brick kilns in Bangladesh are located illegally near 学校.

In a 2024 试点澳门威尼斯人注册网站研究 for this intervention, the researchers learned that zigzag brick kiln owners were unaware of proper zizgag kiln operation—which are already 设计 to be less polluting—or that these approaches could increase their profit. 老板们也对实施干预持怀疑态度，担心这些变化对他们的工人来说技术过于先进。 尽管这项澳门威尼斯人注册网站研究包括了一个实验部门，解释了激励员工采用新做法的商业案例，但这些澳门威尼斯人注册网站研究并没有被广泛采用。 未来澳门威尼斯人注册网站研究的一个重要领域是确定改善工作条件的战略，这些战略符合窑主的利润动机，并可能在监管不力的国家实施。

“From what I’ve seen in brick kilns, the people working there really make all the difference,” says study coauthor Debashish Biswas, assistant scientist at 位于 in Dhaka, Bangladesh. “It’s not just about the technology or the strategies—if the workers aren’t taken care of, things just don’t run smoothly. 我认为这是一个真正的机会，可以找到方法，让照顾员工实际上也能帮助企业，即使这些规则并不总是得到执行。 如果我们能解决这个问题，业主和工人都将受益。”

When assessing the economic burden of the intervention, the researchers found that the social benefits outweighed the costs 65 to 1 by using the social cost of carbon of $185 per metric ton to value the CO₂ reductions. 澳门威尼斯人注册网站研究小组估计，如果孟加拉国的所有之字形窑主都采用这些变化，那么在一个烧砖季节，二氧化碳水平将下降2.4公吨，这将使该国的年二氧化碳排放量减少2%。

“Brick kilns and other informal industries need not always look outside for finding solutions to improve their environmental performance,” says study coauthor Sameer Maithel, an advisor at Greentech Knowledge Solutions in New Delhi, India. “The energy-efficient operating practices introduced in this study were identified working in close partnership with progressive brickmakers in South Asia. 在这个领域有几个这样的创新正在被实践。”

麦塞尔博士说，迫切需要建立一个系统来识别这些创新并加以推广。 澳门威尼斯人注册网站研究人员的节能干预措施可能会在南亚推广，比如在印度和尼泊尔，那里的制砖实践是相似的，也可能在其他行业推广。 未来的澳门威尼斯人注册网站研究将考虑如何最好地扩大干预，以及为砖行业开发下一代效率改进。

“The remarkable success of the intervention demonstrates the benefit of deep engagement with local stakeholders,” says co-senior author 斯蒂芬·露比, Lucy Becker Professor of Medicine and senior fellow at the Stanford Woods Institute for the Environment.

Hear more from Brooks and Luby about these new findings 在本问答中 by the Stanford Woods Institute for the Environment.