Then the biggest oil producer among the OPEC nations, Saudi Arabia, led the move. It was the first oil shock that led industrialists and policymakers to search for a more durable energy base for the industrial economy. The nuclear hope soon dimmed as it proved to be risky as well as expensive. So, after the 1973's oil crisis was over, the race to find fresh fossil fuel reserves only got further momentum. But the Western powers now embroiled in the Ukraine war are facing yet another oil shock of political origin. So, the efforts at developing alternative energy base for industrial and domestic use have now taken the centre stage. But the worst-hit by this new fossil energy crisis are the developing countries which unlike the richer industrialised nations lack the money power to buy oil and gas from the international market for an indefinite period of time. Meanwhile, the climate change is no longer an issue to be debated, though some climate-sceptics with ulterior motives are still in a denial mode. But the seasonal shifts, frequent droughts and downpours, prolonged heat waves with temperatures rising to unprecedented levels, just to name but a few of the fallouts from the global warming, are leaving their devastating impacts on the rich and poor countries alike. It is again the poorer developing nations with fewer resources to mitigate the impact of climate change which are paying the highest price.
The good news is that with the flow of cheaper gas and oil through Russian pipeline drying up due to Ukraine war, the Western industrial economies have now begun to adopt various policies to promote efficient and economical use of energy. At the same time, they are also influencing developing countries to practice the same. For instance, the slogan of circular economy that encourages the so-called 3Rs-reduce, reuse and recycle-- helps save both energy and protect environment. Since Bangladesh is the world's second largest exporter of readymade garment (RMG) products and the main consumers of these items are the European and North American countries, it is not surprising that they have been stressing the reuse of the erstwhile waste from the garment industry. This is to reduce both raw material and energy use. The waste from the garment factories consists of materials that are already processed. So, if the garment waste is used as the fresh input into the production line, a lot of energy and raw material are saved. Additionally, the environment is also saved from further pollution from the garment waste.
However, recycling can be an answer to the wastage of energy and raw materials in other sectors of the economy, too. That would require introduction of sector-specific best practices as well as recycling technologies.
But there are also non-recyclable ingredients of waste. Those usually end up in the urban landfills. These landfills are yet another source of environmental pollution. Especially, the rotting biodegradable materials pollute the air and underground water reservoir. In the advanced countries, the practice had been to incinerate such garbage. Now with technologies available, the focus has turned to convert non-recyclable waste into usable energy in the form of heat, even fuels and electricity. Popularly called 'waste-to-energy', or (WTE), this process takes place through a number of stages. One of which is incineration. The other options include gasification, pyrolysis, anaerobic digestion, and landfill gas recovery. Pyrolysis involves heating up of, especially biomass at very high temperatures in absence of oxygen. This produces volatile products and char. In anaerobic digestion, on the other hand, different kinds of bacteria are used to finally convert biodegradable organic materials into hydrogen, ammonia, organic acids and carbon dioxide.
At the landfills, this process occurs naturally producing mainly methane and carbon dioxide. Methane can be recovered for producing heat and electricity for domestic use as well as domestic purpose.
However, when we talk of WTE, it usually stands for incineration. The reason is, it is the most economically viable technology available so far.
In this connection, a WTE project to be set up at Aminbazar under the Dhaka North City Corporation (DNCC) is a welcome development. To be implemented with the help of Chinese technical and financial support, the project will produce 42.5 MW of electricity a day. China being the world's leading nation in the field of urban waste management, Bangladesh can amply benefit from its experience in this regard. Though WTE through incineration is not entirely about recycling, still it can well help complete the loop of circular economy. This is done by way of converting residual waste, the recycling of which is either not practicable or economically viable. The best option in that case is to convert it to energy through incineration. As planned, the government should go ahead with more such WTE plants across the country. For an energy-starved nation like Bangladesh, nothing can be more welcome than getting electricity from garbage.
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