Let us understand Solid Waste Management and SWM, particularly in India
Solid waste means discarded material including solid, liquid, and semi-solid resulting from domestic, industrial, commercial, Agriculture and Mining operations.
“Municipal solid waste” (MSW) is a term usually applied to a heterogeneous collection of wastes produced in urban areas, the nature of which varies from region to region. The characteristics and quantity of the solid waste generated in a region is not only a function of the living standard and lifestyle of the region’s inhabitants but also of the abundance and type of the region’s natural resources. Urban wastes can be subdivided into two major components — organic and inorganic.
The primary difference between wastes generated in Indian cities and those generated in industrialised countries is the higher organic content characteristic of the former.
Organic Waste components of urban solid waste can be classified into three broad categories:
- Putrescible: Decomposes rapidly and unless carefully controlled, decompose with the production of objectionable odours and visual unpleasantness.
- Fermentable: decompose rapidly, but without the unpleasant accompaniments of putrefaction.
- Non-fermentable: Non-fermentable wastes tend to resist decomposition and, therefore, break down very slowly.
The organic fraction of MSW is an important component, not only because it constitutes a sizable fraction of the solid waste stream in a developing country, but also because of its potentially adverse impact upon public health and environmental quality.
Common Sources of Solid Waste:
Wastes generated by Households, Construction, Commercial, Institutional, Municipal, Industrial, Agricultural activities and Open areas (Sludge, Surface Runoff and Dumping in open areas)
Reasons/ Factors affecting solid waste generation:
- Living standard
- Awareness of people
- Source reduction/recycling
- Geographic location
- Collection Frequency
- Per person income
- Public attitudes
- Size of households
- Population density
- Population increase
Impact/ Effect of solid waste on the environment:
- Groundwater contamination by the leachate generated by the waste dump Surface water contamination by the run-off from the waste dump
- Bad odour, pests, rodents and wind-blown litter in and around the waste dump Generation of inflammable gas (e.g. methane) within the waste dump
- Bird menace above the waste dump which affects the flight of aircraft
- Fires within the waste dump
- Erosion and stability problems relating to slopes of the waste dump
- Epidemics through stray animals
- Acidity to surrounding soil and Release of greenhouse gas.
Health problems during the time of segregation of solid waste:
- Workers and rag-pickers can be infected during picking of biodegradable and Non-biodegradable waste.
- If biodegradable and non-biodegradables or wet and dry wastes are not put separately, it can create a bad odour.
- Possible health hazard includes raised level of infant mortality, non-communicable disease such as hand/leg injury by sharp edge material, respirational infections, eye infection.
- Communicable diseases such as Diarrhoea & dysentery(due to flies), skin disease.
Solid Waste Management Hierarchy:
- Prevent the production of waste, or reduce the amount generated.
- Reduce the toxicity or negative impacts of the waste that is generated.
- Reuse in their current forms the materials recovered from the waste stream.
- Recycle, compost, or recover materials for use as direct or indirect inputs to new products.
- Recover energy by incineration, anaerobic digestion, or similar processes.
- Reduce the volume of waste prior to disposal.
- Dispose of residual solid waste in an environmentally sound manner, generally in landfills
A Municipal Solid Waste Management (MSWM) system includes the following activities:
- Setting policies.
- Developing and enforcing regulations.
- Planning and evaluating municipal MSWM activities by system designers, users, and other stakeholders.
- Using waste characterization studies to adjust systems to the types of waste generated.
- Physically handling waste and recoverable materials, including separation, collection, composting, incineration, and landfilling.
- Marketing recovered materials to brokers or to end-users for industrial, commercial, or small-scale manufacturing purposes.
- Establishing training programs for MSWM workers.
- Carrying out public information and education programs.
- Identifying financial mechanisms and cost recovery systems.
- Establishing prices for services, and creating incentives.
- Managing public sector administrative and operations units.
- Incorporating private sector businesses, including informal sector collectors, processors, and entrepreneurs.
Integrated Waste Management:
It is a frame of reference for designing and implementing new waste management systems and for analysing and optimizing existing systems.
Integrated waste management is based on the concept that all aspects of a waste management system (technical and non-technical) should be analyzed together since they are in fact interrelated and developments in one area frequently affect practices or activities in another area.
Importance of an Integrated Approach:
- Certain problems can be more easily resolved in combination with other aspects of the waste system than on their own. Also, the development of new or improved waste handling in one area can disrupt existing activities in another area unless changes are handled in a coordinated manner.
- The integration allows for capacity or resources to be optimised and, thus, fully utilised; there are frequently economies of scale for equipment or management infrastructure that can be reached only when all of the waste in a region is managed as part of a single system.
- An integrated approach allows for the participation of public, private, and informal sector participants, in roles appropriate for each.
- Some waste management practices are more costly than others, and integrated approaches facilitate the identification and selection of low-cost solutions. Some waste management activities cannot bear any charges, some will always be net expenses, while others may produce an income. An integrated system can result in a range of practices that complement each other in this regard.
- Failure to have an integrated system may mean that the revenue-producing activities are “skimmed off” and treated as profitable, while activities related to maintaining public health and safety fail to secure adequate funding and are operated at low or insufficient levels.
Purpose of recycling of solid waste:
- To Make Environment Clean
- Material volume reduction
- Toxicity reduction
- Conservation of Materials
- To Save Energy
- Reduce Garbage in Landfills
- Reduce pollution
- Natural resources conservation
Sound practices for diverting construction and demolition debris from landfill disposal:
- Waste prevention can be promoted through inventory control and return allowances for construction material. This ensures that unused materials will not get disposed of unnecessarily.
- Selective demolition: This practice involves dismantling, often for recovery, of selected parts of buildings and roadways before the main demolition (wrecking) process is initiated.
- Onsite separation systems: Using multiple smaller containers at a construction or demolition site to store sorted recyclable materials, as opposed to gross disposal of mixed materials in using a single roll-off or compactor.
- Crushing, milling, grinding, and reuse of secondary stone, asphalt, and concrete Materials: These materials can be processed to conform to a number of standards for construction materials. Recovery and reuse of these types of materials are facilitated by the existence of approved specifications for road construction materials and by governmental procurement policies that promote or stimulate the purchase of recyclable materials.
Key steps to making progress in the field of Waste Management:
- Responsible planning and design of an integrated MSWM system, which works to reduce the quantity of waste generated and to handle waste in a coordinated fashion. Essential to this is understanding the nature of the wastes generated.
- Adoption of new strategies for revenue generation that move away from sole reliance on a government-owned and operated MSWM system. A balanced mix of public and private systems can lead to a waste management system that is more flexible and efficient than a wholly publicly-owned and operating system.
- Incorporation of small-scale enterprises and the informal sector into the MSWM system.
- Installation of a system of accountability and responsibility at the local level. Residents and businesses can be motivated to act responsibly in MSWM issues. But, most importantly, accountability entails significantly improving the training and capabilities of the managers and planners responsible for the MSWM system.