ENV-214 Lecture 12: Towards Smart & Sustainable Solid Waste Management PDF

Lecture-12 Towards Smart and Sustainable Solid Waste Management Solutions for Cities ENV-214 Haniyum Maria Khan Senior Lecturer ESM, NSU The Challenge  Global Municipal Solid Waste (MSW) Global urbanization and increasing...

Lecture-12 Towards Smart and Sustainable Solid Waste Management Solutions for Cities ENV-214 Haniyum Maria Khan Senior Lecturer ESM, NSU The Challenge  Global Municipal Solid Waste (MSW) Global urbanization and increasing incomes have resulted in a significant rise in MSW by urban inhabitants in the past 10 years. -.64 kg/person/day to 1.2kg/p/d – and 1.42kg/p/d by 2025 In LAC - the total amount of waste generated per year in this region is 160 million tonnes, with an average per capita value of 1.1 kg/capita/day - Caribbean highest levels Region Waste Generation Per Project Waste Generation per Capita (kg/capita/day) Capital by 2050 Averages Organization for Economic 2.2 2.1 Co-operation and Development Member States (OECD) Latin American and 1.1 1.6 Caribbean (LAC) Middle East and North 1.1 1.43 Africa (MENA) Africa region (AFR) 0.65 0.85 South Asia region (SAR) 0.45 0.77 Europe and Central Asia 1.1 1.5 region (ECA) East Asia and Pacific 0.95 1.5 region (EAP) LAC, Africa, and S. Asia – Solid Waste Management Overview Approx. 60% of LAC waste is disposed in landfills, yet outside capital cities, most waste is deposited in open dumps Waste incineration is very limited in the region, predominately due to costs - Composting (centralized) has not been successful - Recycling limited LAC , Africa, and S. Asia – Solid Waste Management Opportunities Municipal solid waste management is one of the most High organic important services content of waste provided (and controlled) by local in LAC, Africa, governments - and S. Asia implications for the generates city budget, GHGs, methane gas energy, quickly that employment, could be health, environmental captured for protection, energy. resource utilization, political image Solid Waste Management Principles for Sustainable Cities Equity for all citizens to have access to waste management systems for public health reasons; Effectiveness of the waste management system to safely remove the waste; Efficiency to maximize benefits, minimize costs, and Optimize the use of resources; and Sustainability of the system from a technical, environmental, social (cultural), economic, financial, institutional, and political perspective (van de Klundert and Anschütz 2001) Waste – Energy Models/Practices Waste Reduction: prevention, minimization, and reuse – product redesign and stem consumerism Recycling and Materials Recovery: 3Rs generates income and employment ; eg: construction waste  Waste – Energy Models/Practices Composting and Biogas Production: composting of organic matter with oxygen (aerobic) for agricultural fertilizers or fuel; anaerobic digestion – methane collected and combusted for energy; Landfill/Methane Capture: most common among all countries; must be done properly to protect the environment and public health. Landfill gas (LFG) from organic matter decomposition can be recovered and the methane (about 50% of LFG) burned with or without energy recovery to reduce GHG emissions. Incineration/Gasification: burning of waste to reduces volume of waste (up to 90% ); energy recovery models with waste streams with very high amounts of packaging materials, paper, cardboard, plastics and horticultural waste. Burning without energy recovery is not recommended - results in air pollution, health problems. Home Read  Landfill Regulations Because of the many old landfills that still exist that have caused a significant amount of pollution, the environmental protection agencies has set up regulations for municipal solid waste landfills, including measures that prevent or minimize pollution from leachate and methane gas. The regulations include: location, design, operating, groundwater monitoring, closure/post-closure care and corrective action and financing. Location Restriction: Placement of a landfill is a definite problem. The EPA has restrictions based on the geology and ecology of the surrounding area. Following are the six total restrictions. A landfill cannot be placed in: 1) a floodplain, 2) a wetland, 3) a fault zone, 4) areas with high risk of earthquakes, 5) unstable areas, and finally 6) the immediate area of an airport. In addition to the above regulations, the hydrogeology and the demographics of the surrounding area must be considered. No one really aspires to live near a landfill, so it is important to examine how many people live near a potential landfill location and what affects that landfill may have on the community, such as whether or any nearby drinking water wells could potentially be polluted. Favorable hydrogeology keeps any pollution created from migrating or reaching any nearby wells. Factors that should be considered when choosing a landfill are topographic relief, location of the water table, amount of precipitation, type of rock and soil and location of the disposal zone in the surface  Landfill Regulations Design: Modern landfills must be designed with pollution prevention in mind. Modern sanitary landfills must include a liner system, a runoff collection system, a methane collection system, a groundwater monitoring system, and after closure, a cap. Of particular importance is the landfill liner, as seen in Figure 1. Landfill liners have several layers: first, a layer of soil as a foundation for the waste; then, a geotextile layer that lets water through but filters out any little pieces of trash; then, a leachate collection system, which consists of gravel that allows water to filter down to pipes where it is collected; under the leachate collection system, liners are required to have a plastic layer in order to prevent leachate from reaching the groundwater; and finally, liners have an impermeable clay layer to stop any water that may make it through the plastic. Operating: Rules also exist for how landfill owners must operate their landfills. They must compact and cover the waste each day. A well-designed landfill has a methane and water collection system, which are also part of the daily landfill operations. Finally, landfill owners must take measures to ensure that the area is restricted so no one can illegally dump hazardous waste.  Landfill Regulations Groundwater Monitoring: The groundwater down gradient of a landfill must be continually monitored for contamination. If the presence of a contaminant is detected, it might indicate a liner leak or that some surface water has seeped through the collection system. Closure/Post-Closure Monitoring and Corrective Action: Once an owner or operator closes a landfill, s/he is still responsible for any pollution it may cause. Therefore, owners and operators are required to monitor landfills even after closure. Financing: Owners and operators must prove that they can successfully finance the landfill.  Landfill Regulations Landfill Construction When landfills are constructed today, a liner — specified by the EPA — must be installed in the landfill. The liners are engineered to stop water from filtering through the soil to the groundwater below the landfill, but in all sanitary landfills, water is found in the leachate collection system below the liner. Some landfill owners go above and beyond the call of duty and install a second leachate collection system below the clay since water sometimes still manages to find its way into the clay layer. How can that be? With plastic and impermeable clay layers, how can liquid still manage to get through? Well, many things can happen to cause this leakage. First, imagine laying down plastic over an entire football field. Plastic that wide does not exist, so smaller pieces must be pieced together. Engineers take great care to make the seams as tight and leak-proof as possible using special machines (as shown in Figure on the next slide, right), but as students will discover in the associated Eek! It Leaks! activity, it is very hard to create perfect seams. Furthermore, piling tons and tons of garbage on top of liners creates a lot of pressure, and the seams could stretch and leak over time. Also, the liner is too big for a few people to just roll out and put together. Construction engineers use big trucks, such as the one shown in Figure (left). Although necessary for installation, trucks are heavy and sometimes puncture or weaken the liner, making a little hole through which liquids can leak. Finally, some chemicals that may be dumped in the landfill can deteriorate the liner material, causing leakage. And, over time, most liners deteriorate. Landfill Regulations https://www.dep.pa.gov/Pa ges/default.aspx  Waste to Energy Model – Gasification Benefits: Feedstock flexibility, Product flexibility, Near-zero emissions, High efficiency, Energy security Challenges: high capital costs; institutionalized waste mgmt system; economies of scale (~1 million inhabitants) Comprehensive estimate for separated dried household waste : 1 ton of input = 1.3MW - 1.7MW electric net output. (~700 homes (OECD)) calorific value of approx. 12 - 14 MJ/Nm3 @ gross electric efficiency of 80%. 10-Year Framework of Programme (10 YFP) on Sustainable Consumption and Production (SCP) adopted at Rio+20 Conference SCP is about promoting resource and energy efficiency and sustainable infrastructure while offering opportunities such as creating new markets and generating green and decent jobs, such as markets for organic food, fair trade, sustainable housing, renewable energy, sustainable transport and tourism. SCP is especially beneficial for developing countries as it provides an opportunity for them to “leapfrog” to more resource-efficient, environmentally sound and competitive technologies, allowing them to bypass inefficient and polluting phases of development A sustainable city includes compact, efficient land use; less automobile use yet with better access; efficient resource use, less pollution and waste; the restoration of natural systems; good housing and living environments; a healthy social ecology; sustainable economics; community participation and involvement; and preservation of local culture and wisdom. Brazil, Colombia, Cuba, the Dominican Republic, Ecuador, Mexico, Peru and Uruguay have developed national action plans, http://www.unep.org/resourceefficiency/Home/Assessme nt/tabid/55520/Default.aspx http://www.unep.org/10yfp/  Durban Adaptation Charter http://durbanadaptationcharter.org Global Agreement/platform launched at the United Nations Framework Convention on Climate Change (UNFCCC) Conference of the Parties (COP) 17 2011). Signed by over 1000 cities committing themselves to: Availability of urban data and local government plans Ensuring that adaptation strategies are aligned with mitigation strategies; Promoting the use of adaptation that recognizes the needs of vulnerable communities and ensuring sustainable local economic development; Prioritizing the role of functioning ecosystems as core municipal green infrastructure; Seeking innovative funding mechanisms.  USAID CityLinks Program supports Durban Adaptation Charter Peer – Peer Exchanges: Ft. Lauderdale/Broward County – City of Durban, South Africa, http://icma.org/en/international/news/Article/103913/CityLinks_Contributes_to_Cli mate_Change_Coordination Outcomes: - City of Durban learns from Broward County’s model of regional adaptation - Southeast Florida Regional Climate Change Compact, http://southeastfloridaclimatecompact.org/ Florida counties (Broward, Miami-Dade, Monroe, and Palm Beach) engage int’l process and demonstrate solidarity to global adaptation and importance of sub-national engagement and cooperation by signing the Durban Charter. Home Work What should we do with the garbage we produce every year? Write all ideas and eliminate ideas that are not practical, such as sending garbage to the sun (most classes come up with this idea, and it is too expensive). Also, eliminate ideas that pollute the Earth, such as do nothing or dump garbage into the sea. The idea is to come up with a list of what we might do with garbage, including incineration, sanitary landfills, compositing, and open dumps. What are some things you can think of, that can cause landfill liners to leak?