New Tweets

[🇧🇩] Save the Rivers/Forests/Hills-----Save the Environment

G Bangladesh Defense
[🇧🇩] Save the Rivers/Forests/Hills-----Save the Environment
427
6K
More threads by Saif


CO2 mineralisation can help curb pollution in Bangladesh

1740699809013.png

Once a vital lifeline for Dhaka, the Buriganga River now faces severe pollution from chemical waste, medical disposal, and plastic debris. FILE PHOTO: STAR

Bangladesh's industrial boom has propelled economic growth, but at what cost? Rivers that once sustained communities, such as the Buriganga and Shitalakkhya, are now some of the most polluted in the country. Industrial waste, textile dye effluents, heavy metals, and untreated sewage have turned these rivers into toxic cesspools, posing serious threats to public health and biodiversity. The Buriganga alone absorbs 21,600 cubic metres of toxic waste daily, mainly from tanneries, textile mills, and chemical factories, according to a study presented at the IICSD conference in 2015. With no robust wastewater treatment infrastructure, the challenge of industrial pollution looms large. However, an emerging technology called CO2 mineralisation offers a game-changing solution that not only captures industrial CO2 emissions but also neutralises harmful contaminants before they reach our lives.

CO2 mineralisation is a form of carbon capture, utilisation, and storage (CCUS) that converts captured CO2 into stable carbonates through reactions with alkaline industrial byproducts like cement kiln dust, steel slag, and fly ash. This process permanently stores CO2 in solid form, preventing it from re-entering the atmosphere, while also neutralising harmful contaminants in industrial wastewater. The result is a dual benefit: reducing emissions and mitigating water pollution.

Globally, companies like Holcim, CarbonCure, and Carbon Clean are pioneering large-scale CO2 mineralisation projects. These initiatives have demonstrated that the technology is not only effective, but also economically viable. Bangladesh has already explored carbon credit markets, selling 2.53 million carbon credits worth $16.25 million since 2006. Integrating CO2 mineralisation into its industrial zones could unlock both environmental and financial rewards for the country.

The textile and tannery industries, which drive much of Bangladesh's economy, are also among the biggest sources of pollution. In areas like Hazaribagh and Savar in Dhaka, leather processing releases highly toxic substances, including chromium, sulphides, and acids, directly into the Buriganga River. CO2 mineralisation can neutralise these hazardous chemicals by introducing CO2-reactive alkaline materials that convert them into non-leachable, harmless compounds, preventing further contamination. A similar approach can be applied to wastewater from textile dyeing, which is often laden with sulphates, phosphates, and heavy metals. Through CO2-induced precipitation, these toxic substances can be removed before they are discharged, significantly reducing water pollution. This aligns with successful global initiatives like CarbonCure's concrete technology, which injects CO2 into concrete mixtures to enhance durability while reducing emissions.

CO2 mineralisation not only cleans wastewater but also repurposes industrial waste into valuable materials. Bangladesh's cement and steel factories generate large amounts of slag, fly ash, and kiln dust, all of which can store CO2 permanently. Instead of accumulating hazardous waste, these materials can be converted into carbonate-rich products, providing a sustainable alternative to traditional construction materials. This approach is used in Canada, where captured CO2 is infused into concrete, strengthening the materials while permanently sequestering carbon. Adopting this method in Bangladesh could significantly reduce the cement industry's carbon footprint and address the country's growing industrial waste problem.

One of the biggest concerns surrounding CO2 mineralisation is its high initial cost. However, Bangladesh can offset these costs by leveraging its carbon credit market, which has already shown success in renewable energy projects. Incorporating CO2 mineralisation into its industries could generate millions of dollars annually from carbon offset sales under mechanisms such as the Clean Development Mechanism (CDM) and Article 6 of the Paris Agreement. Additionally, international climate finance, including grants from the Green Climate Fund (GCF) and loans from the World Bank, could provide the funding necessary for pilot projects and full-scale implementation. Public-private partnerships (PPPs) could also facilitate financing the transition. Beyond financial incentives, repurposing industrial byproducts into construction-grade materials could create new revenue streams for businesses, reduce dependency on imported building materials, and promote sustainable infrastructure development.

The environmental and social benefits of CO2 mineralisation are equally compelling. Restoring cleaner rivers would improve public health by reducing exposure to toxic pollutants. Fishermen, farmers, and communities that rely on these waterways would regain access to cleaner water sources, improving livelihoods. The reduced carbon footprint of major industries would contribute to Bangladesh's climate commitments, helping the country emerge as a leader in sustainable industrial practices.

Unfortunately, despite its enormous potential, CO2 mineralisation in Bangladesh faces several obstacles. The high initial investment required for implementation, coupled with a lack of supportive policy frameworks, hinders its adoption. Additionally, many industries remain unaware of the economic and environmental benefits of this technology, creating a gap in awareness and willingness to invest. However, the landscape is shifting. The Bangladesh Climate Change Trust Fund (BCCTF) and international initiatives like the Green Climate Fund (GCF) are potential sources of financing that could help bridge the cost gap. Furthermore, the growing global interest in carbon trading markets could provide the financial incentives needed to encourage industries to integrate CO2 mineralisation into their waste management strategies. Countries like Norway and the Netherlands have already established carbon trading programmes, proving that emissions reductions can be monetised. If Bangladesh follows a similar path, it could turn CO2 reduction into an economic asset while simultaneously improving its environmental footprint.

Bangladesh's industrial success does not have to come at the expense of environmental health. CO2 mineralisation offers a revolutionary approach to transform pollution into progress, providing a pathway to cleaner rivers, reduced carbon emissions, and new economic opportunities. Technology exists and funding mechanisms are within reach. The only question that remains is: how soon will Bangladesh take action?

Akash Talapatra is a PhD student at Virginia Tech in Virginia, US.​
 

Protecting arable lands in a land-scarce country
Wasi Ahmed
Published :
Mar 04, 2025 23:04
Updated :
Mar 04, 2025 23:04

1741142272806.png


In a land-scarce country like Bangladesh, the steady loss of arable land remains a pressing concern, often posing significant challenges to achieving various developmental goals. A key issue is the uncertainty surrounding the actual rate at which agricultural land is diminishing. Conflicting reports and, at times, exaggerated estimates create confusion, making it difficult to ascertain fundamental details-such as the precise extent of land currently under cultivation, the portion allocated for industrial use, and the areas absorbed by expanding human settlements.

Such information is indispensable for policymakers and urban planners, enabling them to make informed decisions on a range of issues, many of which extend beyond agriculture and food production. Effective land-use planning is essential not only for ensuring food security but also for maintaining ecological balance, optimising industrial expansion and addressing the housing needs of a growing population. Therefore, establishing a comprehensive and transparent land monitoring system-leveraging modern technology such as satellite imagery, geographic information systems (GIS), and digital land registries-is imperative. Only with accurate, up-to-date information can the nation strike a sustainable balance between development imperatives and the protection of its vital agricultural resources.

Studies conducted in the past revealed that the country was losing around 1.0 per cent of its agricultural land annually. According to an agricultural census conducted in 1983-84, the country's total agricultural land was estimated at 9.2 million hectares. A subsequent study done in 1996 showed a considerable decrease in farm lands amounting to 8.2 million hectares. This went to show the annual loss at 1.0 per cent. But findings of a study conducted few years ago by the country's lead NGO BRAC revealed a somewhat relieving picture. Between 1983 and 2008, the study says, decrease in cultivable land was to the tune of an annual rate of 0.3 per cent. A subsequent study showed the annual rate of decrease at 0.4 per cent between 2010 to 2020.

While a database of the size of agricultural lands is crucial, there is also the need for accurate data about the reclaimed lands that the government has been announcing for some time now but not providing precise information as to their size.

In recent times there is an apparent note of complacency due to bumper harvests of paddy, but the matter of food security, anticipated as a result of increased production of the staple food, does not seem to hold ground as decrease in farm lands is accompanied by a considerable decrease in the number of rural population engaged in agro profession.

Now, while credible data is important, equally important it is to know the reasons behind the losses. The reasons are not many, but how these impact the loss and the measures needed to check are matters that require urgent attention from the concerned quarters. Offsetting the losses, to the maximum extent possible, through adoption of a combination of policies and actions could be the right way to address the situation.

It is quite clear that at the root of the loss, the number one factor is the increased demand for land as a result of an increasing population. More and more lands are required for raising homesteads, and the requirement is met mostly by agricultural lands. As per 2001 population census, the total number of homesteads in the country was 24.85 million which rose to 28.66 million as per 2018 agricultural census - at a growth rate of more than 15 per cent.

Similar is the case with the requirements of roads that come with increased population and decrease in agricultural lands. Coupled with it is the recurrence of river erosion that takes its toll on farm lands. As per estimates of the Centre for Geographic Information Services (CGIS), river erosion costs 1,600 hectares of agricultural land every year. Besides these, the menace of brick fields coming up mostly on farm lands has been a cause for serious concern for quite some time.

Looking at the overall picture, it appears that loss of farm lands could have been partly protected had there been a legal bar on the use of agricultural lands for purposes other than cultivation. Opinions expressed many a time by concerned quarters in the past to bring some legal instrument in force so that agricultural lands could be protected have gone unheeded.

While the loss of farm land is an issue of serious magnitude, there is also the need to examine a number of allied matters that need important findings by way of intensive research. For example, the need to examine economic returns of farm lands being used for non-agricultural purposes is one such. There is thus the need for research not just to update the available farm lands including those being reportedly reclaimed, but also to disseminate findings on a host of inter-related matters to facilitate macro planning.

It is here that the need for a comprehensive master plan becomes crucial-one that can identify the problems and suggest measures to address them as well as find ways to utilise arable lands in the most efficient manner.​
 

Elephant trapped in mud rescued after 22 hours

1741305087669.png

Photo: Collected

An elephant that got stuck in the mud in the Chunati Wildlife Sanctuary in Banshkhali upazila was rescued after 22 hours.

The rescue operation, which took place around 5:00pm yesterday, was conducted by the Forest Department with the help of around 35 villagers.

Anisuzzaman Sheikh, ranger of the Jaldee Range of the Forest Department, told The Daily Star that they were informed about the trapped elephant around 7:00pm on Wednesday.

"We began rescue operations around 8:00am today [Thursday]," he said.

The female elephant is around 40 years old.

Anisuzzaman said after the rescue, the elephant was given saline water to help rehydrate.

"We have requested veterinarians from the Dulahazara Safari Park to treat the elephant," he added.​
 

No alternative to restore Dhaka canals: Rizwana

1741307096896.png

Photo: Helemul Alam

Environment Adviser Syeda Rizwana Hasan today said there is no alternative to excavating the canals to solve Dhaka's waterlogging issues and restoration of water flow in the canals is a must.

During a visit in Baunia canal at Mirpur and Khidir canal at Uttara, she said that preserving these canals is essential to maintaining the city's biodiversity.

She also said, "Dhaka North City Corporation has already begun excavating six canals, and by the end of this year, a total of 19 canals will be restored. This initiative will not only prevent flooding but also help replenish the groundwater level."

DNCC administrator Mohammad Azaz said, "We have taken initiatives to recover and excavate canals, alongside eviction drives to remove illegal encroachments. The progress of these development activities is already visible. Additionally, to prevent water pollution, we are working to disconnect untreated sewage lines from buildings."

He said they have met leaders from Gulshan, Banani, and Baridhara societies, instructing them to install ETPs (Effluent Treatment Plants) in every building within a short timeframe.

Meanwhile, DNCC and DSCC have launched a restoration programme for 19 canals. The first phase, which started on February 2 involves restoring six canals -- four in DNCC (Baunia, Karail, Rupnagar, and Begunbari) and two in DSCC (Manda and Kalunagar).

The programme includes boundary demarcation, canal cleaning, bank protection, and the development of a blue network to enhance water flow and connectivity across the city.​
 

Don’t let river grabbers contest polls
HRPB urges EC to amend RPO

1741307259668.png


Rights organisation Human Rights and Peace for Bangladesh (HRPB) yesterday submitted a memorandum to the Election Commission requesting it to amend the Representation of the People Order (RPO), incorporating a provision to disqualify the river polluters and encroachers from elections.

A delegation of HRPB led by its president Advocate Manzill Murshid placed the memorandum to the EC at its office.

Earlier, the High Court in 2016 ordered a provision in this regard.

The Supreme Court also suggested that the grabbers and polluters should be disqualified from contesting the elections.

Despite the suggestions, no law has been formulated in this regard, said HRPB.​
 

Bangladesh must switch to hollow blocks to reduce pollution
Says Concord Group Managing Director Shahriar Kamal

View attachment 13509

Clay bricks cost Tk 12 per piece. A hollow block, which is four times larger than a clay brick, is priced at Tk 50.

This price difference suggests a competitive edge for clay bricks in the construction market.

But the true cost of traditional bricks extends far beyond their purchase price.

Overlooked factors include Dhaka's frequent ranking as one of the world's most polluted cities. This severe air pollution, largely caused by brick kilns, is responsible for a tragically shortened lifespan for many people.

"This cannot continue," said Shahriar Kamal, managing director of the construction conglomerate Concord Group, in an interview with The Daily Star. "To reduce pollution, we need to switch to green alternatives as soon as possible."

Kamal's firm has been producing concrete and hollow blocks since 1998.

They built the 17-acre Lake City Concord township in Dhaka entirely without using a single clay brick. This township comprises 14 buildings, each rising to 16 storeys.

Given the longstanding reliance on clay bricks in the local construction sector, questions naturally arise regarding the feasibility, cost-effectiveness, and urgency of transitioning to hollow blocks.

Traditional brick kilns extract clay by stripping topsoil from fertile lands, resulting in an annual loss of around 1 percent of the country's arable land.

This practice not only devastates agricultural productivity but also involves the burning of vast amounts of coal and wood, releasing harmful particulates and greenhouse gases into the atmosphere.

"The process is unsustainable," said Kamal. "As construction demand increases each year, the environmental toll intensifies."

In contrast, hollow blocks are manufactured using a more sustainable approach. They are produced with materials such as fly ash, cement, and other industrial by-products. This process does not require burning, as the blocks are simply dried.

According to Kamal, hollow blocks are lighter but have superior strength. Therefore, they are suitable for construction in earthquake-prone regions like Bangladesh.

"Buildings constructed with hollow blocks are much lighter than those built with traditional bricks," he explained. "This reduced weight offers an advantage during earthquakes, minimising the risk of collapse and subsequent casualties."

According to the Managing Director of Concord Group, although hollow blocks offer many advantages, the adoption rate of eco-friendly bricks remains low. Only 5-8 percent of bricks currently in use are eco-friendly.

For the slow shift, he said a lack of awareness among builders, insufficient training for construction workers in the use of these blocks, and a strong entrenched preference for traditional bricks are responsible.

"Many workers are not familiar with how to work with these blocks," said Kamal. "For example, traditional bricks require soaking before use, whereas hollow blocks are installed dry."

"We arranged training for the workers several times," he said, "but this effort needs to be scaled up with government support to ensure nationwide adoption."

Kamal acknowledged that cost is another barrier to the widespread adoption of eco-friendly bricks.

"While eco-friendly bricks may have a slightly higher initial cost compared to traditional bricks, they offer long-term savings," he commented. "Proper planning and mindful design can reduce overall construction costs by about 15 percent."

In 2020, the government announced a policy to replace traditional bricks with eco-friendly blocks in all public projects. This policy aimed to achieve a 10 percent adoption rate in fiscal year (FY) 2019-20, with a gradual phasing out of clay bricks by FY25.

However, slack monitoring and enforcement have hindered progress towards these ambitious goals.

"Implementation is key," Kamal stressed. "We need strong inter-ministerial coordination, led by the Ministry of Environment, to oversee the implementation of these policies. Regulatory bodies like Rajdhani Unnayan Kartripakkha (Rajuk) must also play a crucial role by enforcing these targets in private-sector construction projects."

He pointed to successful examples from countries like China and India, where the adoption of eco-friendly bricks has been accelerated through a combination of financial incentives, strict enforcement of environmental regulations, and comprehensive public awareness campaigns.

Kamal said their facilities have the capacity to manufacture 200,000 eco-friendly bricks, blocks, and tiles every eight hours. But, without enough demand, they cannot operate at full capacity.

He called for a range of policy measures to stimulate demand, including financial incentives for manufacturers of eco-friendly building materials and penalties on polluting industries to ensure accountability.

"The polluters must pay," he commented.

"This isn't just about bricks," he said. "It's about rethinking how we build our cities and protect our people. Change is difficult, but it is necessary — and it begins with each of us."

Currently, the size of the traditional brick industry is around Tk 9,000 crore, while the concrete block market is only at Tk 200 crore.

Bangladesh produces an estimated 2,300 crore bricks annually. Concrete blocks currently account for a relatively small share of this market, constituting roughly 6-7 percent of the total.

There are 164 registered factories producing concrete blocks, with an annual production capacity of 214 crore blocks. However, considering the unregistered factories, the total number is more than 250.

Kamal said the concrete block market is projected to capture up to 50 percent of the market share by 2030, due mainly to government policies and a steadily increasing demand for sustainable building materials.

He said large-scale factories have heavily invested in automated production units, often imported from China, with typical investments ranging from Tk 30-Tk 50 crore. Mid-sized factories have also invested in modernising their production lines, with typical investments ranging from Tk 5-Tk 6 crore.

Major industry players, including Concord, Mir Group, BTI, and Meghna, currently collectively control nearly 20 percent of the hollow block market.​

For Low-rise structural construction (and high-rise non-structural curtain wall usage in lieu of drywall/gypsum-board sheet), Bangladesh needs to switch to Aircrete (AAC) blocks now which is quiet a bit lighter, almost half as much. As Bangladesh high-rises are increasingly built of steel beams nowadays instead of RCC, this could alleviate any settling problems in the foundation.

Plus Aircrete (AAC) blocks and pre-fab walls are by nature far better insulators, saving on heating or cooling energy, setting superior ecological precedent than current construction materials used in South Asia.

Aircrete blocks are significantly lighter than regular concrete blocks, with densities typically ranging from 460 to 730 kg/m³, while regular dense concrete blocks are much heavier (By spec should have a minimum block-density of around 1500 kg/m³). This reduced weight makes Aircrete blocks much easier to handle and install, contributing to lower labor costs and faster construction times.

Aerated concrete (AAC) or ‘Aircrete’ blocks are the lightest of the family of concrete blocks. Aerated blocks are distinguished by their capacity to perform a dual structural / insulation function. Though limited to structural applications in low-rise construction and partitions as well as a component of curtain walling in higher buildings, aerated blocks can perform a similar range of functions as dense and lightweight blocks.

Here is more info,


And a video. Granted Western usage but could be adapted to South Asian situation.

 
Last edited:

A major quake striking BD not a remote possibility
Atiqul Kabir Tuhin
Published :
Mar 08, 2025 22:53
Updated :
Mar 08, 2025 23:06
Share this news

1741482859566.png


The frequent low-intensity tremors felt in various parts of Bangladesh due to earthquakes in neighbouring countries serve as a grim reminder of the country's seismic vulnerability. Over the past 10 days, Bangladesh has experienced four earthquakes. The most recent one, on Wednesday, had its epicentre approximately 449 kilometres from Dhaka in the border region between India and Myanmar. Despite the distance, it sent a moderate shockwave through Dhaka, registering a magnitude of 5.6 on the Richter scale.

The frequency of low to moderate-intensity earthquakes has been steadily increasing in recent years. According to the Meteorological Department, 28 earthquakes were recorded in Bangladesh and nearby regions in 2017. This number rose to 41 in 2023 and further increased to 54 last year, marking the highest number in eight years.

Even though tremors originating from nearby countries may not always directly and severely impact the country, it does not mean Bangladesh is at a safe distance or that earthquakes pose no real threat. In reality, Bangladesh lies in an active earthquake zone, situated near the meeting points of three major tectonic plates and four active seismic sources in the Bay of Bengal, which have the potential to generate tremors exceeding 7.0 in magnitude. Experts warn that the series of small quakes frequently shaking Dhaka, Sylhet, and Chittagong could be precursors to a devastating seismic event.

Indeed, seismologists have long warned that a powerful earthquake is not a matter of 'if' but 'when.' The fact that Bangladesh has not experienced a major tremor in the past two hundred years only increases the likelihood of a catastrophic event. The last major earthquake to impact the region was the 1897 Great Indian Earthquake of the Shillong Plateau, which jolted the northeastern part of the country with a magnitude of 8.7.

An earthquake often proves more devastating than other natural calamities because, unlike storms, floods, and droughts, it cannot be predicted with precision. When prevention is impossible, the focus must shift to damage limitation, immediate rescue, relief, and rehabilitation. But is Bangladesh prepared?

While the country has experience in dealing with floods and cyclones, it lacks the capacity to handle a major earthquake. In past incidents, when multi-storied structures collapsed for various reasons, the fire service took an inordinately long time to clear the rubble. Even in cases of fire outbreaks, the fire department struggles to bring blazes under control swiftly. This highlights the lack of advanced equipment and expertise required for clearing debris, cutting through concrete, and rescuing trapped victims. A key priority, therefore, should be to equip the Fire Service and Civil Defence, along with other emergency response organisations, with the necessary resources.

A major earthquake presents the grim prospect of a human catastrophe in Bangladesh, primarily due to the prevalence of a substantial number of unsafe buildings. An estimate suggests that 72,000 out of 2.1 million structures in Dhaka are highly unstable. However, no significant measures have been taken to demolish these buildings or relocate and rehabilitate their residents. Following the Rana Plaza collapse, BUET proposed a comprehensive initiative to classify Dhaka's buildings based on earthquake resistance. Under this plan, high-risk buildings were to be marked red, moderate-risk structures yellow, and earthquake-resistant buildings green. However, this crucial assessment remains incomplete for most structures. The authorities, therefore, must prioritise identifying high-risk buildings, demolishing unsafe structures, and reinforcing weaker ones.

Earthquake preparedness demands massive preparation, investment in advanced rescue equipment, comprehensive emergency response training and raising public awareness. Without immediate and decisive action, a catastrophic loss of life remains an imminent threat.​
 

Members Online

Latest Posts

Back
PKDefense - Recommended Toggle Create