Solid waste management (SWM) is the process of collecting, transporting, processing, recycling, and disposing of solid waste materials. It goes beyond simple garbage disposal, aiming for a systematic and integrated approach to minimize waste’s environmental and health impacts.
Key Categories of Solid Waste
Solid waste is classified based on three main criteria:
• Source: This categorizes waste by its origin. Examples include residential waste (from households), commercial and industrial waste (from businesses and factories), and agricultural waste (from farming activities).
• Content: This classification focuses on the material composition of the waste.
• Organic waste : Biodegradable materials, such as food leftovers and agricultural by-products.
• Plastic waste : Non-biodegradable plastics that are difficult to manage.
• Metallic waste: Industrial by-products that can be hazardous.
• Hazard Potential: This focuses on the risk the waste poses to health and safety.
• Toxic waste: Chemicals and radioactive substances that are dangerous to health.
• Flammable waste: Materials prone to causing fires.
Types and Methods of Solid Waste Management
There are several types of solid waste and corresponding management methods.
Major Waste Types
• Municipal Solid Waste (MSW): Everyday waste from homes, schools, and offices, including plastics, paper, and food scraps.
• Hazardous Waste: Industrial by-products and other materials like e-waste, pesticides, and paints that pose long-term health and environmental risks.
• Biomedical Waste: Waste generated from hospitals and laboratories, such as syringes and bandages. The World Health Organization (WHO) classifies it into eight categories.
Methods of Disposal
• Sanitary Landfills: An engineered disposal method where waste is compacted and covered with a layer of soil. Unlike open dumps, these landfills have liners to prevent groundwater contamination from leaching.
• Incineration: The process of burning waste at high temperatures to reduce its volume and generate energy. It can also destroy pathogens but must be carefully managed to control the release of toxic gases.
• Pyrolysis: The decomposition of organic waste using heat in the absence of oxygen. It is an eco-friendly and energy-producing method.
• Composting and Vermi-Composting: These are biological processes for decomposing organic waste. Composting uses natural microbial decomposition, while vermi-composting uses earthworms to produce nutrient-rich organic manure, both of which can be used as fertilizer.
Solid Waste Management in India
India faces significant challenges in SWM, as only a fraction of the daily municipal solid waste is scientifically processed. A heavy reliance on landfills has led to issues like groundwater contamination and frequent landfill fires, such as the one at the Bhalswa landfill in Delhi.
To address these challenges, the Solid Waste Management (SWM) Rules, 2016, were introduced. Key provisions of these rules include:
• Mandatory source segregation: Waste must be separated into three streams: biodegradable, non-biodegradable, and domestic hazardous waste.
• Extended Producer Responsibility (EPR): Producers are required to manage the disposal of their products and packaging waste.
• Waste-to-energy plants: The rules encourage the establishment of these facilities to process waste and generate power.
• Inclusion of waste pickers: The rules formally recognize and integrate informal waste pickers into the formal waste management system.
Writer: Vaishali Verma