Wednesday, 28 September, 2022

Air Pollution from Brick Kilns and Alternative Solutions

  • Arfa Ahmed
  • 18th September, 2019 12:00:00 AM
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Air Pollution from Brick Kilns and Alternative Solutions

Brick is a popular construction material for thousands of years. At present, the demand of bricks is soaring, especially in the developing country like Bangladesh, where infrastructure development projects are the top priority. Owing to this rapid urbanization, a sharp rise of 5.6 percent per year has been noticed for the construction industry. This trend eventually directed the brick sector to increase annually at projected 2 - 3 percent over the next decade for housing construction and commercial sector developments (WB,2010). Brick-making is a significant sector in Bangladesh, contributing about 1 percent to the country’s gross domestic product (GDP) (BUET 2007) and generating employment for about 1 million people. Due to the unavailability of stone aggregate, brick is the main building material for the country’s construction industry, which grew an average of about 5.6 percent per year in 1995– 2005. Despite the importance of brick- making, the vast majority of kilns use outdated, energy intensive technologies that are highly polluting. This leads to harmful impacts on health, agricultural yields and global warming.

 Though the brick manufacturers in Bangladesh are expanding their production, a good number of these producers are not formally recognized as industry and not advancing technologically (MOI, 2010). The kilns and technology remained unchanged for long time back and still consumes energy inefficiently. Biomass, mainly firewood and rice husk, are the main energy sources for brick firing (Alam, 2009). Brick making is traditionally a cottage industry which produces bricks for local consumption; though its technological development is inadequate. Eventually, brickfields are producing major environmental pollutants. The existing technologies of brick manufacturing as well as their emission exceed the tolerable limit and put a threat to the environment.

The country’s capital, Dhaka, is surrounded by more than 1,200 kilns. Most kilns operate only 6 months during the year (between November and April) because more than 90 percent are located in low-lying areas which experience flooding during the rainy season. During the 6 months of operation, Dhaka becomes one of the most polluted cities in the world. Every day, the chimneys blow black smoke that clouds the city’s sky. The smoke is dense and contains fine particulates, which are very damaging to health. They cause no less than 20 percent of the premature deaths related to urban air pollution in Dhaka.

The current status is by no means sustainable. To make 100,000 bricks, one needs to burn 20 tons of coal, which has high sulphur content. China, the world’s leading brick producer, uses only 6 tons of coal to make the same amount of bricks. China’s experience suggests that adopting cleaner and more energy-efficient technologies is key to success.

Brickfields are the important contributors of the emission of greenhouse gases (Croitoru

& Sarraf, 2010, Narasimha & Nagesha, 2013) in Bangladesh as they burn huge amounts of coal and wood fuel. As a result, rate of deforestation increases in the brick making season of 6 months. If the wood fuel burning is stopped in Brickfields, the Bangladesh Atomic Energy Commission estimates that 2.1 petajoules of energy (Which is equivalent to the energy produced by 2.1×2312×100 tons of refined fossil oil) will be saved.

Burning of wood fuel except bamboo is illegal (GOB, 1989) but till now a huge amount of wood fuel is being used. After the Government regulation in Brickfields, the major fuel used now for brick manufacturing is coal. The conventional practice of firing clay bricks in rural country clamps and BTKs (Bull Trench Kiln) consume huge quantities of fuel in terms of coal, firewood and other biomass fuel such as old tires, tainted sawdust, discarded motor oil, plastic and household garbage, dung cakes and agricultural residue. In Bangladesh, the brick industries consume several million tons of coal biomass fuels; kilns are notorious as highly polluting establishments, affecting not only just flora and fauna but also posing threats to human health.

The main reason for harmful emission from brick kilns is the use of poor quality coal and biomass, mainly firewood. The main pollutants which are emitted from the brickfields are particulate matter (PM), some hazardous gases like CO2, CO, NOX, NO and SO2. The PM concentration appears to be low but it is expected to have long term massive impact on global environments as well as on human health. The particulate matter consists of dust, smoke, fumes, and fly ash.

Nearly 90 percent of the brick-makers have not updated their production process in keeping with new environmental regulations on the fuel, location and use of brick kilns, six months after the deadline set by the government.

The Environment Ministry says a total of 6,637 traditional and modern brickfields are currently operating in Bangladesh. Only 735 of these fields follow the new regulations, says a report by the Bangladesh Centre for Advance Studies (BCAS).

According to the BCAS, 1,745 of the brickfields in Bangladesh begin operations before obtaining a license. Though the government has regulated the use of modern kilns to combat pollution, brick-makers have been reluctant to phase out the older kilns because of profit concerns.

Every year 17.12 billion bricks are manufactured in Bangladesh, according to BCAS. The amount of earth required for it stands to 58.38 billion tons. Wood or coal is used to fuel the traditional brick kilns. The height of the permanent chimneys is, at most, 120 feet. The smoke released from these chimneys damages the ozone layer and pollutes the surrounding area. After demands from environmental activists, the government instituted the Brick Making and Brickfield Establishment (Control) Act 2013, banning permanent chimney brickfield.

 Brick kilns have a negative effect on agricultural productivity. Almost invariably, good-quality topsoil from agricultural fields with high clay content is used in Bangladesh’s brick kilns. Depletion of topsoil with high organic content for brick- making is a major concern for agricultural production. In addition, acid deposits from the sulphur dioxide (SO2) and NOx emitted from the brick kilns negatively affect agricultural productivity.

Chemical radiation continues to affect new crops despite emissions having ceased. Toxic smoke emitted from a Panchagarh brick kiln has scorched crops on hundreds of acres of land and vegetation surrounding the area.

This incident occurred when a brick kiln named KSB, in Shimultali village of Dandapal union— under Debiganj upazila of the district—began producing poisonous smog. Local farmers said crops—such as boro rice, nuts, corn, and other plants—were also destroyed.

About 50 farmers have incurred immense losses due to this gas. In additions to crops, the deadly smoke also singed mango, jackfruit, and olive trees — along with the bamboo shrubs surrounding the area. Although the gas emissions have stopped, the toxic chemical radiation is still affecting plants and new crops.

Locals said the KSB brick kiln was closed off for this year on the night of April 19, when the toxic and mal-odorous smoke started to ooze from its chimney. Although farmers did not realize the extent of damage that night, the next morning they found that crops and tree leaves had begun to shrivel.

In the afternoon, farmers noticed that the plants looked like they have been scorched, and the leaves and fruits began falling off the trees. Because of this radiation, Shimultali,

 Nayanpara, and other nearby villages suffered severe damages. The affected farmers have demanded compensation for their losses.

It’s heartening to find that with government initiative, brick kilns have started to become eco-friendly. Reportedly, 65.29 per cent brick kilns have been upgraded and kilns have been told to produce 20 per cent concrete block bricks, to reduce the production of baked bricks. The government also needs to allay fears among construction companies that concrete bricks are just as solid as baked ones.

In addition, marketing of concrete bricks needs to be carried out vigorously. Kiln owners, who are complying with environmental specifications, can be awarded so others feel encouraged. At the same time, the authority can think about special incentives. There is reason for hope because, in 2018, the Asian Development Bank (ADB) and Bangladesh Bank earmarked $50 million and Tk. 200 crore respectively to provide as soft loans to brick kiln owners so that they may install green technology.

Loans on easy terms need to be handed out with the clause that once the environment friendly technology is in place, the kiln owner must place a request for inspection. Failing to do so within a specified time should result in a fine, to be collected by the Department of Environment with the help of the police station of the respective area.

 The Fixed Chimney Kiln (FCK) dominates the brick sector in Bangladesh, despite its highly polluting and energy-intensive features. Such technologies as the Improved Fixed Chimney Kiln (IFCK), Improved Zigzag Kiln (IZigzag), the Vertical Shaft Brick Kiln (VSBK), and the Hybrid Hoffmann Kiln (HHK) are substantially cleaner, consuming less energy and emitting lower levels of pollutants and greenhouse gases. But implementation of these technologies in Bangladesh is still at a pilot stage; thus, their financial viability still needs to be demonstrated.

Cleaner technologies (i.e. VSBK, HHK) are the most socially profitable ones, while polluting technologies (i.e. FCK) are socially unprofitable. VSBK and HHK are the most socially profitable technologies, with net benefits of TK68-75 per thousand bricks. In contrast, the high costs of air pollution and CO2 emissions make the FCK socially unprofitable, with net social costs of TK3 per thousand bricks. Though socially unprofitable, FCK is the most commonly implemented technology in Bangladesh. FCK accounts for more than 90 percent of brick kilns in Bangladesh. The low investment cost and the ability to operate on lowlands explain the FCK’s dominance in the brick sector.

Adopting cleaner technologies is hindered by their need to operate on flood-free lands (i.e. highlands) which are scarce and expensive. In addition, some technologies (e.g. HHK) require substantial investments, which are unaffordable for most FCK owners who operate on rented land that cannot be used as collateral.

Specific results of the analysis related to the kilns’ social and environmental impacts suggest that:

•             Currently, FCKs contribute up to 20 percent of the total premature mortality caused by urban air pollution in Dhaka (all causes combined). The Bangladesh Country Environmental Analysis reports that poor air quality in Dhaka contributed to an estimated 3,500 premature deaths in 2002 (World Bank 2006)7. Emissions of PM10 and PM2.5 from the kiln cluster north of Dhaka are responsible for 750 premature deaths annually. Thus, current FCKs are likely to contribute up to 20 percent of total premature deaths in Dhaka due to poor air quality.

•             Replacing the brick cluster north of Dhaka with VSBKs would reduce current premature mortality by more than 60 percent; replacement by HHKs would reduce it by 45 percent.

•             Adopting the VSBK or HHK can provide considerable carbon benefits. The FCK provides the highest unit cost of carbon emission, primarily because of the high coal consumption. By contrast, the low coal consumption makes the VSBK and the HHK the cleanest technologies in terms of CO2 emissions.

The New Regulations which are associated with brick kilns technology:

-              No individual can cut earth from ponds, canals, marshes, creeks, lakes, rivers, wetlands, sandbars or other areas without permission from appropriate authorities.

-              Wood cannot be used to fuel brick kilns.

-              Coal containing excess amounts of Sulphur, ash, mercury or other such materials cannot be used for brick burning fuel.

-              Bricks and brick making materials cannot be transported to and from the brickfield by road without the permission of a local government engineering department, Upazila authorities, or union authorities or village authorities

-              Traditional brick kilns have to be replaced with tunnel kilns, improved zigzag kilns, or hybrid Hoffman kilns.

-              Brickfields cannot be built within 2 km of educational institutions, residential, business or protected areas, city corporations, municipality or Upazila headquarters, public or private forests, environmental sanctuaries, gardens or wetlands, agricultural land, ecological crisis areas, or areas with high air pollution.

-              Permissions, protections and licenses will not be granted to brickfields in violation of area regulations set by the Environment Ministry or any other authorities.

Barriers facing the brick sector in Bangladesh:

The barriers that have contributed to the current state of the country’s brick sector and its inability to bring about changes include:

-              Lack of supporting regulations, fiscal incentives and standards to encourage more energy efficient practices and technologies. Except for some efforts to regulate the sector, the government has made little effort to establish effective boundary limit emission standards;

-         Little  and  no  governmental  activity  to  assist  the  brick  sector  to  undertake comprehensive programs so as it to make it cleaner and more profitable. Brick owners usually were left to bring in changes of their own which they have often failed to do, because of the vicious cycle of low efficiency – low income.

-         Lack of knowledge and access to energy efficient technology, which can lower production costs at the same time. Comprehensive dissemination programs that demonstrate the potential economic benefits of energy efficient technologies have yet to be carried out.

-              Lack of access to liquidity to finance modernization of brick making operations. As traditional brick kilns have seasonal employment, they have not been included in the list of recognized SMEs and thus, are not eligible for concessional SME loan windows.

-         Lack of capacity in terms of technical and business skills at the enterprise level, that could bring changes towards improved efficiency and reduced pollution.

-              Limited experience of commercial lending institutions with SMEs and in particular, brick SMEs.

                Source: UNDP (2010)


The writer is from the Department of Environmental Science and Management (MESM), North South University