RESUMO
Construction and demolition waste has a high environmental and socio-economic impact due to its poor management infrastructure. In recent years, Dhaka, the capital city of Bangladesh, experienced significant growth in the real estate sector, which demands substantial construction and demolition activities within the city. Most of the construction and demolition waste finds its way to landfills, roadsides, and unapproved locations with a 2% recycling rate through local scrap vendors and unregulated recyclers. In an effort to assess the waste generation rates from ongoing construction and demolition activities, the current study employed the Site Visit method along with direct and indirect waste quantification methodologies for the investigated demolition and construction projects, respectively. The findings indicate that for per unit area (m2) of demolition and construction, the average WGR was found to be approximately 575.0 kg and 73.9 kg, respectively. Projection reveals that by 2025 and 2030, within Dhaka City, construction and demolition activities will generate roughly 1.15 MT and 1.69 MT of construction and demolition waste if no recycling actions are considered. Additionally, the results highlight the recycling potential of construction and demolition waste with respect to economic benefits through the maximum recycling rates for the relevant materials. Furthermore, to address the future of sustainable construction and demolition waste management infrastructure, this paper presents a detailed overview of the current onsite construction and demolition waste management practices as well as safety protocols for demolition and construction activities.
Assuntos
Monitoramento Ambiental , Gerenciamento de Resíduos , Bangladesh , ReciclagemRESUMO
The SARS-CoV-2 pandemic has demonstrated both positive and negative effects on the environment. Major concerns over personal hygiene, mandated and ease in lockdown actions and slackening of some policy measures have led to a massive surge in the use of disposable personal protective equipment (PPE) and other single-use plastic items. This generated an enormous amount of plastic waste from both healthcare and household units, and will continue to do so for the foreseeable future. Apart from the healthcare workers, the general public have become accustomed to using PPE. These habits are threatening the land and marine environment with immense loads of plastic waste, due to improper disposal practices across the world, especially in developing nations. Contaminated PPE has already made its way to the oceans which will inevitably produce plastic particles alongside other pathogen-driven diseases. This study provided an estimation-based approach in quantifying the amount of contaminated plastic waste that can be expected daily from the massive usage of PPE (e.g. facemasks) because of the countrywide mandated regulations on PPE usage. The situation of Bangladesh has been analysed and projections revealed that a total of 3.4 billion pieces of single-use facemask, hand sanitizer bottles, hand gloves and disposable polyethylene bags will be produced monthly, which will give rise to 472.30 t of disposable plastic waste per day. The equations provided for the quantification of waste from used single-use plastic and PPE can be used for other countries for rough estimations. Then, the discussed recommendations will help concerned authorities and policy makers to design effective response plans. Sustainable plastic waste management for the current and post-pandemic period can be imagined and acted upon.
Assuntos
COVID-19 , Equipamento de Proteção Individual , Bangladesh , Controle de Doenças Transmissíveis , Humanos , Pandemias , Plásticos , SARS-CoV-2RESUMO
The COVID-19 pandemic and lockdown situation have shown both positive and negative effects on the environmental aspects. With an unprecedented rate the different types of waste volume have up surged along with the COVID-19 contamination rate. As the situation has mandated people as well as the most infected persons to stay at home, the amount of generated hazardous waste is 3.40 kg that can be expected daily from each infected person. China and other countries have seen a massive increment in the hazardous waste generation (about 600 % increase in Hubei province) amount. While dealing with this sudden increase in waste amount, the conventional incineration facilities have been outstripped and waste management industry is facing an immense pressure over handling hazardous waste generated from COVID-19 infected patients. Alongside with the hazardous waste volume, single-use plastic items and personal protective equipment (PPEs) have induced a new type of "PPE pollution" in the land and aquatic environment. The current review provides a countrywide waste generation amount, estimated using the infected number of cases for some selected countries. In contrast with the poor waste management noticed during this pandemic, some suggested approaches towards a better waste management service and future implications of waste management are discussed with viable consideration for the waste workers.
RESUMO
Bangladesh is 10th among the major plastic waste contributor countries of the globe. Throughout the world, plastic waste disposal is a major concern since it is being nonbiodegradable in nature and hazardous, because of its potential harmful effect on human health and to the environment. Various studies have shown that waste PET (polyethylene terephthalate) plastic bottle filled with sand or other inorganic materials can serve as a useful building material where plastic waste management or recycling process is not very effective and particularly, in low-income communities. Plastic brick use in existing Rohingya refugee camp and newly proposed displacement camp in the coast island-Bhasan Char-as construction material to build new shelters, can be a sustainable use and management of country's plastic waste, and a feasible solution against the shelter issues of Rohingya people. The vulnerability due to heavy wind, monsoon rains, cyclones, and the gaps and lack in funding to build new rigid and safe shelters can be effectively mitigated by using this low-cost, environment-friendly plastic brick as building block in refugee camps.