TEP4310 Lecture Notes PDF

Lecture 1: Materials and Waste Material use Raw material categories: nonmetallic minerals, biomass, fossil energy carriers, ores,... Finished materials examples: cement, steel, paper, plastics,... Product examples: books, wallpaper, food packaging, textiles, cars, … Quantifying impacts: IPAT equati...

Lecture 1: Materials and Waste Material use Raw material categories: nonmetallic minerals, biomass, fossil energy carriers, ores,... Finished materials examples: cement, steel, paper, plastics,... Product examples: books, wallpaper, food packaging, textiles, cars, … Quantifying impacts: IPAT equation 𝐼=𝑃*𝐴*𝑇 I = impact P = population A = affluence T = Technology For material consumption $ 𝑡𝑜𝑛𝑛𝑒𝑠 𝐼=𝑃* 𝑝𝑜𝑝𝑢𝑙𝑎𝑡𝑖𝑜𝑛 * $ I = material consumption P = total population (of a country) $ A = annual gross domestic product (GDP) in 𝑝𝑜𝑝𝑢𝑙𝑎𝑡𝑖𝑜𝑛 𝑡𝑜𝑛𝑛𝑒𝑠 T = among of material per unit of economic output in $ - Countries with larger populations use more materials. - Higher-income countries with larger economies use more materials. - Countries with larger primary industries such as extraction use more materials. Lifecycle stages of materials and products 1. Extraction/Production Primary industries such as agriculture, forestry, fishing, mining, and quarrying provide primary feedstocks. These feedstocks are then turned into useful materials. 2. Manufacturing Processing primary or secondary feedstocks into finished materials such as iron ores or steel scrap into steel and products such as cars. 3. Use Materials and products are consumed, burnt, and used in durable applications. Durable products remain largely unaltered. 4. Treatment and recovery Recycling, utilization, and waste management. Separating components of the waste and recovering its material or energy value. 5. Land disposal Final stage for materials and products that are not cycled back to earlier stages. Waste Waste is a leftover, redundant product or material of no marginal value for the owner and which the owner wants to discard. - Waste: any substance or object that the holder discards or intends or is required to discard. - Hazardous waste: waste that displays one or more of the hazardous properties listed in Annex III. - Municipal waste, waste collected from households, doesn't include industrial waste. Composition of household waste - Higher-income households generally generate more waste per capita per day and less organic waste compared to lower-income households. - Waste compositions change depending on the seasons. Lecture 2: The impacts of waste Relationship between SDGs and waste management Environmental impact of waste DPSIR Framework - Drivers: different processes from extraction to disposal. - Pressures: emitted substances and environmental impact categories such as water withdrawal and land use change. - States: mediums where the changes occur. - Impacts: human health, natural environment, natural resources. - Responds Social impact of waste Waste workers are associated with lower social status, poverty, and marginalization. There exist negative social norms such as dirty or unhygienic views. People overestimate the risks associated with second-hand products compared to new products. Affects social impacts such as way of life, culture, political system, health & well-being, and personal & property rights. Waste economics - Economic aspects of waste management - Resource utilization - Waste minimization and recycling - Environmental and social costs - Sustainable waste management Annaulization of investment cost 𝐴 = 𝐼 * 𝐶𝑅𝐹 I = initial investment cost Capital recovery factor 𝑇 𝑞*(1+𝑞) 𝐶𝑅𝐹 = 𝑇 (1+𝑞) −1 q = alternative rate of return: represents the interest that could have been earned by investing money in another activity T = lifetime of the capital in years Value of future costs and benefits 𝑃𝑉 𝐹𝑉 = 𝑇 (1+𝑟) PV = past value FV = future value r = real discount rate T = time Net present value 𝑡=𝑇 𝐵 −𝐶 𝐵𝑡−𝐶𝑡 𝑡 𝑡 1 𝑁𝑃𝑉 = ∑ 𝑡 = 𝑟 * (1 − 𝑇 ) 𝑡=0 (1+𝑟) (1+𝑟) Ct = value of costs in period t Bt = value of benefits in period t (revenues) r = real discount rate T = time horizon in years Lecture 3: Assessment Methods: MFA, LCA and others Material flow analysis (MFA) - Represents physical systems in a mathematically defined way. - Is based on mass and energy conservation. - Can identify inefficiencies in waste management. - Can suggest improvements in processes. Life cycle assessment (LCA) - Identifies environmental impacts across all lifecycle stages. - Goes beyond MFA by mapping material flows and assessing impacts. Substitution potential γ = λ * η𝑟𝑒𝑐 * 𝑆 * 𝑀 γ = substitution potential: measures change in product consumption due to co-product supply λ = physical resource potential: amount of secondary resource in a waste stream η𝑟𝑒𝑐 = resource recovery efficiency: share of resources recovered and utilized S = substitutability: functional equivalence of alternative resources/products M = market response: change in consumption of affected products Lecture 4: Policy and Legislation International trend in waste management policy 1. Waste Framework Directive (WFD) EU Adopted in 1975 and defines waste and provides guidelines for waste classification and management. 2. Resource Conservation and Recovery Act (RCRA) US Governs waste classification and sets waste management principles. 3. Solife Waste Law China Provides a framework for waste classification and management principles. Common themes in waste laws: they define what constitutes waste, offer systems for waste classification, lay down principles for waste management, and are supported by additional legislation in each region. Main principles in waste legislation - principle: polluters must bear the cost of environmental damage either directly or indirectly. - Integrated pollution and prevention control (IPPC): all emissions and environmental impacts from installations must be regulated and reduced to acceptable levels. - International regulations: compliance with global agreements such as the Montreal Protocol and the Basel Convention. Regulation and waste management Aims - Waste minimization - Reduce impact on the environment - Circularity Components - Environmental goals - Economics - Regulations - Technology - Organization and administration Regulations Regulations describe specific obligations and liabilities and what the operators can do with the waste. The waste sector is one of the most regulated in modern society. Examples - Land zoning: where can a treatment unit be built? - Wastewater regulations: how does the leachate from a landfill have to be treated? - Emission regulations: which emission limits must be fulfilled by an incineration plant? Regulatory instruments - Economic instruments: taxes, subsidies, refundable deposits (pant),... - Voluntary agreements between authorities and business societies: limit the use of disposal plastic bags, and return expired medicine to pharmacies,... - Technical guidelines and documents: references from court decisions. - Additional requirements in call for tenders: noise restriction for collection vehicles. Strategies for setting up good waste policies 1. Circular economy package (regulatory framework with numerous policy instruments) Shifting from linear to circular economy. 2. Extended producer principle (product take-back schemes) Putting legal responsibilities to the producers to prevent pollution and minimize negative consequences. 3. Industrial symbiosis projects Instead of only producing products and waste from natural resources, the waste can be turned into resources which can again be turned into products with less waste. Lecture 5: Waste Prevention and Minimization Waste prevention Waste prevention describes prevention and/or reducing the amount of waste at the source. It improves the quality of the waste and reduces toxicity along the whole value chain. Purpose - Reducing resource demands and hidden flows. - Reducing environmental and health impacts from waste management. - Reducing social conflicts from waste landfills and incinerators. - Economic resources becoming available for other priorities. Clean Technology: It has a life-cycle approach and aims at avoiding environmental pollution at the source. It considers all kinds of environmental impacts including waste prevention. Example: replacing fossil into renewable energy sources for production. Clean Production: It aims at the production of goods and services with minimal environmental impact. It is subjected to present technological and economic limits. Clean-up Technology: It describes adapting or modifying an established plant/process to reduce the environmental impact. Example: glue gas cleaning system. Waste minimization Waste minimization includes waste prevention + Recycling + Energy recovery of waste. 1. Waste prevention at the company level Companies focus on production, market, and economic survival - not on waste management, making the cost usually the determining factor for waste management. - Making the producers responsible can help along with regulations, guidelines, and penalties. 2. Waste prevention at the residence level Understanding the importance of waste prevention is essential. Through changes in lifestyle and habits over the last years, waste prevention has been counteracted: by fast fashion trends, an increased number of convenience products, and a decrease in household size. - Households should buy durable and recycled products, repair products, borrow/rent products, and donate unwanted products. Indicator & Strategy As WP is a new field, there is little experience and knowledge on how to measure progress and the developed indicators are mostly on a very aggregated level. For future development, a lifecycle perspective should be incorporated for identifying the policy intervention points and social and economic aspects need to be integrated into environmental policy discussions on WP. Lecture 6: Collection and Treatment Collection methods Source separation: waste is sorted at the point of disposal into categories Mixed waste collection: all waste is collected in a single stream without sorting Challenges of sorting method - Wastes are typically not washed. - Contaminated packages including food and drinks. - Most products are composed of several materials. - Magazine papers containing fillers. - Low-quality cardboard containing staples, ink, and glues. Material recovery facility (MRF) 1. Workers manually separate oversize products, valuable items, and contaminants. 2. A trommel separates large or undersized pieces that could jam the sorting equipment. 3. A ballistic separator separates flat objects from three-dimensional objects. 4. A magnet removes ferrous metal from the glass stream. 5. An optical sorter separates plastics with an air knife. Glass sorting 1. Pre-sorting: size reduction and removal of large contaminants. 2. Optical sorting: optical sensors detect different wavelengths of light reflected by the glass. 3. Precise sorting: air jets blow specific pieces of glass into different collection bins. 4. Further cleaning: metal detection and removal + ceramics and stone removal. Treatment methods 1. Physical treatment Size reduction, mixing, or separation of solid materials, including storage of waste as a treatment method. Common facilities: MRFs and industrial waste treatment plants 2. Physicochemical treatment Combines physical and chemical processes aiming to separate waste components or make waste less hazardous/reactive. 3. Biological treatment Reducing waste volume, reactivity, and pathogen content by producing valuable nutrient streams or energy. Used in composting, anaerobic digestion, and on-site industrial waste treatment plants. 4. Thermal treatment Separating components or reducing waste volume, reactivity, or hazardousness by converting organic waste into fuels or energy. Occurs in industrial energy-from-waste plants and MSW (municipal solid waste) incinerators. Lecture 7: Material Recycling Impact factors - Economic: costs and values - Technology: sortability of feedstock and technical feasibility - Environmental impact Product quality - Material composition: purity, degradation - Physical properties: strength, durability, appearance, density - Chemical properties: contaminants, resistance to degradation - Regulatory compliance: safety standards, certifications Glass recycling Recycling glass is relatively easy to recycle and the prices of recycled glass have been decreasing due to the following reasons: - Oversupply: increased availability of recycled glass due to a higher recycling rate - Reduced demand: due to shift to plastic / alternative materials Metal recycling Steel production is a high energy-demanding process and steel is one of the most recycled materials in the world. Recycled material has almost the same quality as the new materials. Paper recycling Recycled papers are mainly used for packaging and graphic papers. - Fibers in paper get shorter as they get recycled. - Around 10% are discarded every year. Plastic recycling Worldwide, only 9% of plastics are recycled. In Norway, around 21% is recycled. - There are different kinds of plastics and prices. - They are produced from fossil oil. - Plastics are relatively cheap, easy to form, have good strength, and have long durability. - Many plastic bottles are recycled into synthetic fibers. Mechanical recycling of plastics 1. Collection 2. Sorting 3. Washing 4. Grinding into flakes 5. Melting and granulation 6. New product Main challenge: polymers that are not sortable - Food and medical packaging. - Consists of multilayers to improve mechanical and physical properties and shelf-life. Solutions: biodegradable plastics, enzymes, thermo-chemical recycling Different recycling methods & their advantages and disadvantages. Lecture 8: Waste to Energy - Part 1 Purpose - To replace the use of fossil fuel through energy recovery. - To reduce the volume of waste for landfilling. - To treat hygienic and medical waste. Mechanical technology Refuse-derived fuel (RDF) - Feedstocks: commercial and industrial waste, recycling rejects, and mainly paper and plastics. - Converting feedstocks into fuel by mechanically processing and separating the waste. - Reducing the wastes’ sizes removing non-combustible materials and creating higher energy-content material. Landfill gas - Generating landfill gas from anaerobic decomposition of organic waste materials in landfills. - Landfill gas is collected and captured as it is produced through a series of pipes and wells. - The gas is processed and used to generate electricity. Thermal treatment - Includes incineration, gasification, and pyrolysis. - Heating waste materials at high temperatures to break them down and convert them into energy or other by-products. Hydrothermal carbonization (HTC) - Converting wet biomass or organic waste into a hydrochar (carbon-rich solid), mimicking the natural formation of coal. Lecture 9: Waste to Energy - Part 2 Waste-to-Energy (WtE) plant Combustion technology - Oxygen is required for the oxidization of elements and overall the plant is operated with a surplus of air. - Emissions are formed from air combustion, waste components, and others (combustion process or added). Energy recovery technology - Flue gas from combustion heats up in the boiler which turns into steam and runs the turbine and generates electricity. - Byproducts: process steam with high temperature and district heating with lower temperature. Flue gas cleaning - Gas phase emissions: dust and fine particles, NOx, acidic gasses (HCI, HF, SO2), heavy metals (Pb, Sb,...). - CO2 does not count as an emission. - Dust removal: cyclone and electrostatic precipitator (ESP) - Acid gas neutralization: removing acids with or without neutralizing agents and activated carbon adsorption. - Reduction of dioxins and furans: activated carbon adsorption or catalytic filtration method. - Reduction of NOx: air staging, selective noncatalytic reduction (SNCR), and selective catalytic reduction (SCR). Lecture 10: Waste to Energy - Part 3 Biowaste treatment technologies Aim: to reduce environmental burden and return resources. 1. Composting (aerobic degradation) Organic waste + air + microbial activity → New biomass + water + heat - To obtain a biologically stable end-product, to destroy pathogens, and to retain a maximal nutrient content in the compost. - Only the easily degradable components are converted and few fibers such as cellulose and lignins are not converted. - Open composting: Wastes are piled up into a long pile and mixed with the crane equipment, and are composted for 12-20 weeks.  - Enclosed composting: Constructed with a hood to capture created gas. - Process factors: temperature, moisture, oxygen availability, nutrient availability, acidity, and particle size. - Advantages: simple and inexpensive. - Disadvantages: relatively small weight reduction, a large part of MSW can’t be composted, land area requirement, and odor problem. 2. Anaerobic digestion Organic waste + enzymes → New biomass + CH4 + CO2 - To recover energy (biogas) from the organic waste feedstock, to obtain a bio-residual product with nutrient content for land use, and to destroy pathogens. - Hydrolysis: breaking up larger organic molecules → Fermentation: conversion to organic acids and CO2 → Acetogenesis: conversion to acetate and CO2 → Methanogenesis: conversion to residuals, CO2, and CH4. - Controlling factors: pH and temperature. - Advantages: needs smaller area and reduced odor via biogas combustion - Disadvantages: higher complexity, more expensive, and higher strength wastewater formed. Lecture 11: Disposal Landfill EU landfill directives - Reducing biodegradable waste sent to landfills. - Preventing risks to soil, air, and water. - Emphasizing that landfilling is the last resort after waste hierarchy steps. - Landfill reduction target: 10% of the total amount of municipal waste by 2035. Landfill gas - Highly explosive gas formations such as CO2 and methane. Leachate’s pollution potential parameters - Biochemical oxygen demand (BOD) assesses the amount of oxygen microbes require to break down bioorganic materials over a specific time period. - Chemical oxygen demand (COD): measures the amount of oxygen required to break down total organic compounds via chemical oxidation. - As leachates are harmful, they need to be treated before being stored somewhere. Historical development of landfilling 1. Open dumps: has significant environmental issues in urban areas. 2. Sanitary landfill: organized and covered landfill design lacking landfill gas and leachate collection and treatment system. 3. Controlled landfill: liners and treatment systems used for leachate and gas. 4. Dry tomb landfill: minimizes water infiltration to slow degradation.  5. Bioreactor landfill: accelerates waste degradation and stabilization through controlled moisture and aeration. Multibarrier concept in landfilling - Location type barriers: considering the distance from groundwater, geological stable strata, and place above ground. - Inputs: limit water types or required pretreatment before landfilling. - Design: bottom liners and drainage collection system, top covers, and monitoring leachate generation and surrounding groundwater. Lecture 12: WEEE recycling The green shift from the EU Solutions must be created to repair and ensure the product's lifetime expands. The producer’s responsibility is extended. Digital product passport Introduced by the European Commission aimed at transparency and traceability. Includes product information throughout its lifecycle for stakeholders, manufacturers, and consumers. What is it and why do we need it? The critical raw material act It will be the guiding principle for the legislation which is being prepared now. E-Waste Extended producer responsibility: producers and importers are responsible for costs throughout a product’s life cycle including removing the environmental toxins from discarded products and taking care of the resources in the waste. - EE waste stream grows the fastest in the world however only 20% is properly recycled in the world. - In Europe, 55% of all WEEE is treated properly with a worldwide collection rate of 17%. Lecture 12: Special wastes - hazardous Hazardous wastes are dangerous because if they are disposed of incorrectly, they can cause severe damage and/or accidents Hazardous waste Waste that can’t be appropriately handled together with consumer waste because it can cause serious pollution or the risk of harm to people or animals. Hazard classes 1. Health hazards 2. Physical hazards 3. Environmental hazards Hazardous properties of waste - Explosive - Ammunition and fireworks - Corrosive - Acidic, basic detergents, acidic and alkaline organic wastes - Flammable - Fuel, heating oil, paint, and glue - Toxic - Pesticides, old thermometers, and isocyanates Hazardous household wastes - Batteries - Bleach, chloride, ammonia - Lightbulbs - Paint, stain, glue Declaration of hazardous waste ADR European Agreement concerning the International Carriage of Dangerous Goods by Road RID Regulations concerning the International Carriage of Dangerous Goods by Rail Hazardous waste is treated through energy recovery, recycling, destruction, and landfilling. Exam preparation “Reflect”: describe advantages and disadvantages Things to remember - I=PAT - Waste economics equations - Heating value equations similar to exercise (subtracting ashe values) - Frameworks such as LCA: main elements of LCA, differences of methods for waste management - EU/Norway targets - The expense of waste management processes: treatment, collection, disposal,... - EU-level waste legislation and its aims - Different types of emissions along with their importance in capturement and their impacts - Circular economy definition, aim, impact,... Learning outcomes Knowledge The student shall have acquired knowledge of the following: 1. Strategies and solutions for solid waste management and recycling and resource recovery from waste systems 2. Theory regarding technologies for waste management and resource recovery from waste. Skills The student shall be able to 1. Explain the elements of waste policy 2. Explain the main elements of waste generation and characterization 3. Explain common technical solutions and designs for the collection and treatment of waste and resource recovery from waste 4. Interpret life cycle assessment studies of waste systems 5. Reflect on important requirements for effective and environmentally friendly solid waste systems. General competence The student shall be able to 1. Adopt a systems perspective in the assessment of solutions and systems for solid waste management 2. Be able to communicate in good ways with specialists and decision-makers.