MUNICIPAL solid waste or garbage generation is increasing with rapidly increasing urban population in developing countries. Sustainable waste management is a major challenge for mega cities like Dhaka with 20 million people and smaller cities. The availability of land for building waste management systems (landfills, composting, recycling, and/or waste to energy) can constrain the decision making. However, we need to pay special attention to availability of land and applicability of technology in a specific region (based on the waste characteristics) because what works for developed countries like USA, Japan or South Korea may not be applicable to Bangladesh.
Waste to energy or incineration can provide a lucrative solution to waste management as WTE plants may address the issue of land in both developed and developing countries. The incineration system requires limited land and can process a large volume of waste in a single processing plant. It is an appropriate technology for waste management in developed countries (European countries, USA, Japan and South Korea) as their waste is relatively dry, and the presence of a large amount of plastics, paper, and other combustible materials make it a good source of energy.
The prime minister of Bangladesh is the winner of the United Nations Champions of the Earth and the constitution of the country was amended, under her leadership in 2011, to include a constitutional directive to the state to protect the environment and natural resources for current and future generations (William Brittlebank, Climate Action 2015). The current decision of adopting waste management through WTE or incineration is directly in contrast with the policy of vision of the premier and plan for a sustainable urban environment for Bangladesh.
When considering the WTE in developing economies and Bangladesh, there are major issues that need in-depth feasibility studies and evaluations.
Waste in developing countries like Bangladesh has high amount of food waste (more than 70 per cent), and moisture content compared to similar waste in European countries. Generating power through WTE or incineration using this low calorific (organic waste), highly wet waste is neither applicable, not cost-effective. However, following the success of the WTE plant in Europe and intense lobbying from many WTE companies, many developing countries including Bangladesh are trying to use WTE technology without understanding the applicability of the WTE/incineration technology or their serious environmental and public health consequences. WTE is not an appropriate technology for Bangladesh.
For Bangladesh, it is a very expensive operation, both in term of initial capital investment and operating cost of the WTE. Moreover, the technology does not apply to the type of waste we are dealing in Bangladesh and other developing countries.
There are many environmental and public health concerns around the WTE operation. The waste to energy plant generates 20 per cent bottom ash from burning the waste. In most cases, there is no plan for managing the generated bottom ash. They end up in our water bodies polluting the nearby rivers and creating a serious problem for clean water and agricultural lands. There are reported difficulties in controlling air pollution from the toxic emission of WTE plants. Incinerator emissions are also a source of particulate matter (PM 2.5) — tiny particles of dust that can lead to decreased lung function, irregular heartbeat, heart attacks, and premature death. On March 23, 2019, the South Delhi residents organised one of the largest open-chain rallies to protest the Okhla waste-to-energy (WTE) plant. Their complaint against the plant, which generates electricity by burning waste, is spewing toxic fumes, filling the atmosphere with stench, and making people ill. ‘The number of asthma patients admitted to emergency and intensive care units have gone up since the plant was set up,’ says Shailendra Bhadoriya, consultant cardiologist, Fortis Escorts Heart Institute, one of the three hospitals operating in close proximity to the plant.
There are other concerns that must be considered as well. For example, the possible correlation between the death from COVID 19 and WTE. In Wuhan, China, North Italy and USA, death from COVID 19 are higher than any other places in the world and all three places have a high number of WTE plants. Just a coincidence? Beth Gardiner, a journalist with the National Geography sited a research of T H Chan School of Public Health in Harvard University, which has analysed data on PM2.5 levels and COVID-19 deaths from about 3,000 US counties covering 98 per cent of the US population and in conclusion said, counties that averaged just one microgram per cubic meter more PM2.5 in the air had a COVID-19 death rate that was 15 per cent higher (National Geography, April 8 2020). These tiny particles PM2.5, emitted from incineration plants, penetrate deep inside the body and increase possibility of hypertension, heart disease, breathing trouble, and diabetes, all of which increase complications in coronavirus patients. Francesca Dominici, a biostatistician at Harvard University said, ‘If you’re getting COVID, and you have been breathing polluted air, it’s really putting gasoline on a fire’.
In 1987, the old Timarpur WTE plant in Delhi, India, had to shut down the facility just 21 days after opening due to operational failure brought upon by low calorific value of incoming waste (2.5-2.9 MJ/kg) (Shah, 2011). Since 1990, 14 WTE plants were installed in India; however, half of them has already been closed and the remaining ones are also under scrutiny for possible closure (Down-to-earth, 2019). Along with the low calorific value and high moisture content of MSW, the presence of inert materials in MSW has also failed several projects in developing nations.
The major alternative solution to WTE is to consider waste as resource and design ‘Sustainable Resource Management Facility’. The SRMF include maximum material recovery and diversion (through recycling, composting, cost effective locality based Anaerobic Digester) before final disposal and processing of waste through perpetual landfill and/or WTE. Perpetual landfill, system operated as biocell that recycles landfill space can continue its operation in same place for as long as 200 years at a stretch. This addresses the issue of space availability for construction of new landfills in every 20-30 years. Moreover, collection of generated gas through AD and biocell and conversion to electricity can provide access to electricity in remote areas where electric grids are not available. The SRMF will create green jobs and become a perfect example of circular economy in developing countries.
Md Sahadat Hossian is the director of Solid Waste Institute for Sustainability and professor of department of civil engineering at the University of Texas at Arlington, Texas, USA,