Presentation on theme: "SOLID AND HAZARDOUS WASTES Akay Meliko ğ lu Baran Gülsün Cem Çiftçi Burak Gür Meltem Bayrak."— Presentation transcript:
SOLID AND HAZARDOUS WASTES Akay Meliko ğ lu Baran Gülsün Cem Çiftçi Burak Gür Meltem Bayrak
Outline Introduction Definitions I. Solid wastes II. Hazardous wastes III. Non-hazardous wastes Acute hazardous wastes, advantages and disadvantages Types of wastes Institutions that is established for waste management
Daily average waste per person
Essential Definitions Solid Wastes: Any unwanted or discarded material that is not a liquid or a gas. It can include organic waste, paper, metals, glass, cloth, construction wastes, yard waste and wood.
Hazardous Wastes Hazardous waste is waste that is dangerous or potentially harmful to our health or the environment. Hazardous wastes can be liquids, solids, gases. They can be discarded commercial products, like cleaning fluids or pesticides, or the by-products of manufacturing processes
Most Common properties of Hazardous wastes Flammability Reactivity Corrosivity Toxicity
Eutrophication due to Fertilizers Eutrophication: is the response of the ecosystem to the addition of artificial or natural substances, such as nitrates and phosphates, through fertilizers, to an aquatic system. Which results to exponential growth of the algae and phytoplanktons.
3R: Reuse, Reduce, Recycle. A proper waste management plan should be implemented to promote waste minimization at source. If waste generation is unavoidable then the potential for recycling or reuse should be explored and opportunities taken. If wastes cannot be recycled then the recommended disposal routes should be followed. 1. Source Reduction 2. Recycling 3. Reuse
Reduce Source reduction is one of the fundamental ways to reduce waste. Can be done by using less material when making a product reuse of products on site designing products or packaging to reduce their quantity. On an individual level we can reduce the use of unnecessary items while shopping, buy items with minimal packaging, avoid buying disposable items and also avoid asking for plastic carry bags.
Recycle Recycling : Process to change (waste) materials into new products to prevent waste of potentially useful materials. Recycling benefits conservation of resources reduction in energy used during manufacture reducing pollution levels Some materials such as aluminum and steel can be recycled many times. Mining of new aluminum is expensive and hence recycled aluminum has a strong market and plays a significant role in the aluminum industry. Metal, paper, glass and plastics are recyclable. Paper recycling can also help preserve forests as it takes about 17 trees to make one ton of paper. Crushed glass (cullet) reduces the energy required to manufacture new glass by 50 percent and reducing air pollution.
Collection of Recyclable Materials A number of different systems have been implemented to collect recyclates from the general waste stream. The three main categories of collection are; Drop off centers Buy back centers Curbside Collection
Collection of Recyclable Materials Drop-off centers require the waste producer to carry the recyclates to a central location, either an installed or mobile collection station or the reprocessing plant itself. They are the easiest type of collection to establish, but suffer from low and unpredictable throughput. Buy-back centres differ in that the cleaned recyclates are purchased, thus providing a clear incentive for use and creating a stable supply.
Sorting Once recyclates are collected they aredelivered to a central collection facility. The different types of materials must be sorted. A series of stages, many of which involve automated processes such that a truckload of material can be fully sorted in less than an hour. Some plants can now sort the materials automatically, known as single-stream recycling. In plants a variety of materials are sorted such as paper, different types of plastics, glass, metals, food scraps, and most types of batteries.
Problems of Recycling The problems associated with recycling are either technical or economical. Plastics are difficult to recycle because of the different types of polymer resins used in their production. Since each type has its own chemical makeup different plastics cannot be recycled together. Thus separation of different plastics before recycling is necessary. Similarly in recycled paper the fibers are weakened and it is difficult to control the color of the recycled product. Recycled paper is banned for use in food containers to prevent the possibility of contamination. It very often costs less to transport raw paper pulp than scrap paper. Collection, sorting and transport account for about 90 percent of the cost of paper recycling.
Composting Composting is the controlled decomposition of organic matter.
Type of composting Active (hot) composting ~55 o C Higher temperature kill most pathogens Regularly stirring ensure aeration Faster (take weeks) Passive (cold) composting ~30 o C Much slower (may take months) May develop anaerobic condition, releasing odor and greenhouse gas (e.g. methane)
Incineration Facilities Generates energy from wastes
Energy Generation from waste
Case study Love Canal Disaster Love canal is a province of near Niagara Falls, NY Hooker chemicals and plastics used the area for landfill, buried 21000 tons of chemical waste under the soil in 1940s After the landfill process is done, company sold the area for $1 to the state. More than 100 houses and a school has built to the area By 1970s, chemical wastes began to bubble up into backyards, cellars and ground water. Which eventually poisoned thousands of people All the families had to evacuate their houses.
Consequences Burns in skin Choking if inhaled Feints Birth defects Miscarriages Death of plant ecosystem Highly increased cancer cases
Aerial photo from 1978
Satellite photo from 2010
Question What is the proper waste management plan ? What should we do if waste generation is unavoidable ? Answer: First step is to reduce the source of the waste. If waste generation is unavoidable, then reuse and recycle mechanisms should be applied.
Related videos Recycling: http://www.youtube.com/watch?v=Y68tBxVrnXg http://www.youtube.com/watch?v=Y68tBxVrnXg Composting: http://www.youtube.com/watch?v=ZAMy_ZJ0Xa8 http://www.youtube.com/watch?v=ZAMy_ZJ0Xa8 Love Canal Disaster: http://www.youtube.com/watch?v=Kjobz14i8kM
Thanks For Your Attention!
SOLID WASTE Solid waste, commonly known as trash or garbage, is a waste type consisting of everyday items that are discarded by the public.
COMPOSITION The composition of solid waste varies greatly from country to country and changes significantly with time.
Countries which have a developed recycling culture The waste stream consists mainly of intractable wastes such as plastic film, and un-recyclable packaging. At the start of the 20th century, the majority of domestic waste (53%) in the UK consisted of coal ash from open fires
Developed countries without significant recycling It includes food wastes, yard wastes, containers and product packaging, and other miscellaneous wastes from residential, commercial, institutional, and industrial sources.
TYPES OF SOLID WASTES Most definitions of solid waste do not include industrial wastes, agricultural wastes, medical waste, radioactive waste or sewage sludge. Biodegradable waste: food and kitchen waste, green waste, paper
TYPES OF SOLID WASTES Recyclable material: paper, glass, bottles, cans, metals, certain plastics, fabrics, clothes, batteries etc.
TYPES OF SOLID WASTES Inert waste: construction and demolition waste, dirt, rocks, debris.
TYPES OF SOLID WASTES Electrical and electronic waste (WEEE) - electrical appliances, TVs, computers, screens, etc.
TYPES OF SOLID WASTES Composite wastes: waste clothing, Tetra Packs, waste plastics such as toys.
TYPES OF SOLID WASTES Hazardous waste including most paints, chemicals, light bulbs, fluorescent tubes, spray cans, fertilizer and containers
TYPES OF SOLID WASTES Toxic waste including pesticide, herbicides, fungicides
TYPES OF SOLID WASTES Medical waste: discarded surgical gloves, surgical instruments, needles etc.
SOURCES AND TYPES OF SOLID WASTES Residential: Food wastes, paper, cardboard, plastics, textiles, leather, yard wastes, wood, glass, metals, ashes, special wastes (e.g., bulky items, consumer electronics, white goods, batteries, oil, tires), and household hazardous wastes.). Generators: Single and multifamily dwellings
SOURCES AND TYPES OF SOLID WASTES Industrial: Housekeeping wastes, packaging, food wastes, construction and demolition materials, hazardous wastes, ashes, special wastes. Generators: Light and heavy manufacturing, fabrication, construction sites, power and chemical plants.
SOURCES AND TYPES OF SOLID WASTES Commercial: Paper, cardboard, plastics, wood, food wastes, glass, metals, special wastes, hazardous wastes. Generators: Stores, hotels, restaurants, markets, office buildings, etc. Institutional: Same as commercial. Generators: Schools, hospitals, prisons, government centers.
SOURCES AND TYPES OF SOLID WASTES Construction and demolition: Wood, steel, concrete, dirt, etc. Generators: New construction sites, road repair, renovation sites, demolition of buildings
SOURCES AND TYPES OF SOLID WASTES Municipal services: Street sweepings; landscape and tree trimmings; general wastes from parks, beaches, and other recreational areas; sludge. Generators: Street cleaning, landscaping, parks, beaches, other recreational areas, water and wastewater treatment plants.
SOURCES AND TYPES OF SOLID WASTES Process (manufacturing, etc.): Industrial process wastes, scrap materials, off-specification products, slay, tailings. Generators: Heavy and light manufacturing, refineries, chemical plants, power plants, mineral extraction and processing.
QUESTION? Name four of the solid waste types and give an example to each of them. Answer: Biodegradable waste: food and kitchen waste. Recyclable material: paper. Inert waste: construction and demolition waste. Composite wastes: waste clothing. Etc.
How Humans are exposed to solid wastes? Ingestion of contaminated food or water Contact with disease vectors Inhalation Dermal contact
Contaminated water and food
Contact with disease vectors
Impacts of Solid Waste on Health Chemical poisoning through inhalation Nausea, vomiting Cancer Low birth weight Congenital Malformation Neurological diseases
Effects on animals and aquatic life Mercury accumulation in aquatic animals Plastic waste ingestion of birds Eutrophication Decreased soil and water quality
Mercury accumulation in aquatic animals
Plastic waste ingestion of birds
Decreased soil and water quality
Impacts of solid wastes to environment Waste breakdown in landfills to form methane which is a greenhouse gas Change in climate and destruction of ozone layer due to biodegradable wastes. Health issues and diseases caused by pollution of soil, water and air
Question What are the main factors of the exponantially increasing pollution of the world?
Storage of Wastes
Storage: Holding of hazardous waste for a temporary period until the waste is transported, treated or disposed. Container: Any portable device which has a capacity that doesn’t exceed 454 liters. Storage Facility: Place where hazardous wastes are stored in tanks or containers. Tank: A stationary device to contain an accumulation of hazardous waste which is constructed primarly of non- earthen materials such as wood, concrete, steel and plastic.
Storage of Wastes When storing hazardous waste or recyclables, containers must be: In good condition and not leaking Protected from the weather Compatible with the materials they are storing to avoid corrosion or chemical reactions that could result in fire Kept closed except when adding waste Not opened, handled or stored in ways that could cause leaks or ruptures Clearly marked and labeled to identify what is being stored
Storage of Wastes In addition, the following requirements and precautions should be taken: Clean up any spills immediately Do not store incompatible wastes together Have in place secondary containment for liquid hazardous waste/recyclables Use separate containers and appropriate barriers between different waste to prevent contact in the event of a release Inspect waste and recyclables in storage weekly and note any deterioration or corrosion in an inspection log
Storage of Wastes Properly Stored Improperly Stored
Waste Storage Site Hazardous wastes and recyclables must be stored in a place that allows for safe handling (store facility) and is prepared for emergencies. The storage facility must: Prevent access by unauthorized persons Be posted as a hazardous waste/recyclables storage area Have proper equipment to handle emergency situations Have designated people responsible for the site and able to respond to emergency situations Be designed and maintained to ensure run-off cannot enter the secondary containment system Be located away from sewer drains, manholes, drainage courses and standing water
Waste Storage Sites
Waste Collection and Transportation The transfer of solid waste from the point of use and disposal to the point of treatment or landfill. Waste collection vehicles or manually
Waste Collection and Transportation Transportation system has to be designed so that it is efficient, yet cost effective. The system should synchronize with the system of waste storage depot and should be easily maintainable.
Waste Loading Types Manual Loading: In most of the cities/towns there is no synchronization between waste storage depots and transportation of waste. Waste stored in open spaces is either loaded manually or with the help of loaders in traditional trucks. Manual loading takes time and reduces the productivity of the vehicles and manpower deployed. Manual handling of waste poses a threat to the health of the sanitation workers as the waste is highly contaminated.
Waste Collection Vehicles Garbage trucks There are five basic models: Front loaders Rear loaders Side loaders Pneumatic collection Grapple trucks
Transfer Stations In large cities where disposal sites are more than 10 km. away from the city boundary and smaller vehicles are used for transportation of waste, it may prove economical to set up transfer stations to save transportation time and fuel provided such cities have a good performance record of vehicle maintenance and adequate facilities to maintain large size vehicles and containers. A transfer station is a building or processing site for the temporary deposition of waste. Transfer stations are often used as places where local waste collection vehicles will deposit their waste cargo prior to loading into larger vehicles. These larger vehicles will transport the waste to the end point of disposal in an incinerator, landfill, or hazardous waste facility, or for recycling In the future, transfer stations could be equipped with material recovery facilities and with localized mechanical biological treatment systems to remove recyclable items from the waste stream.
Measures to be taken Transportation of waste has to be planned scientifically System of transportation should be such that it can be easily maintained departmentally or through private garages The system should match with the system adopted for the storage of waste at the waste storage depots. Manual loading should be discouraged and phased out expeditiously and replaced by direct lifting of containers through hydraulic system or non-hydraulic devices or direct loading of waste into transport vehicles. Transportation of waste should be done regularly to ensure that the containers /trolleys and dustbin sites are cleared before they start overflowing.
Disposal Disposal of solid waste is done most commonly through a sanitary landfill or through combustion. In Turkey there are some open dumping sites which are very dangerous.
1993 Ümraniye Open Dumping Explosion Explosion due to generation of methane 27 dead and 12 missing
Sanitary Landfill Sanitary landfills are sites where waste is isolated from the environment until it is safe. Sanitary landfills are one of the most popular methods for disposing of waste. This technique for waste management was developed in the 1930s, in response to growing pressures created by a growing population. It’s goal is accomplished when it has completely degraded biologically, chemically and physically. In high-income countries, the level of isolation achieved may be high. However, such an expensive high level of isolation may not be technically necessary to protect public health.
Sanitary Landfill Requirements The site for a sanitary landfill needs to be selected with care. It should be located above the water table, in an area which is not geologically active. They are generally not located in immediate proximity to residential communities. The land also must be inexpensive to make the cost of operating the landfill worth it, and it must be accessible to roads so that garbage can be easily delivered.
Problems of Sanitary Landfill One of the biggest problems with a sanitary landfill is the environmental hazard. As materials inside the layers of compacted garbage break down, they generate gases, including methane, which are flammable. Some landfills simply vent these gases, while others actively trap them, using them as fuel. Landfills also generate leachates, materials which could damage the natural environment if they end up in the water table, making control of leaching critical.
Problems of Sanitary Landfills Incomplete Decomposition: Commonly used plastics resist natural decomposition because of their molecular structure. Microbes can’t digest these compounds.
Basic Control Conditions of Landfills As a minimum, four basic conditions should be met by any site design and operations before it can be regarded as a sanitary landfill: Full or partial hydrogeological isolation: if a site cannot be located on land which naturally contains leachate security, additional lining materials should be brought to the site to reduce leakage from the base of the site (leachate) and help reduce contamination of groundwater and surrounding soil. Formal engineering preparations: designs should be developed from local geological and hydrogeological investigations. A waste disposal plan and a final restoration plan should also be developed. Permanent control: trained staff should be based at the landfill to supervise site preparation and construction, the depositing of waste and the regular operation and maintenance. Planned waste emplacement and covering: waste should be spread in layers and compacted. A small working area which is covered daily helps make the waste less accessible to pests and vermin.
Example Sanitary Landfill
From Landfills to playing fields Some landfills are converted to community places, offices or other complexes for reuse.
Combustion This process is waste reduction not disposal, because after incineration the ash must still be disposed of.
Advantages of Combustion Combustion can reduce the weight of trash by more than 70% and the volume by 90% thus greatly extending the life of a landfill. No changes needed in trash collection procedures. Waste to energy.
Problems of Combustion Air pollution and offensive odors as dioxin emmisions (dioxin is highly toxic) Facilities are expensive to build and their siting can be a problem. Ash is often loaded with hazardous materials which must be disposed in secure landfills.
Question Prevent access by unauthorized persons Be posted as a hazardous waste/recyclables storage area Have proper equipment to handle emergency situations Have designated people responsible for the site and able to respond to emergency situations Be designed and maintained to ensure run-off cannot enter the secondary containment system Be located away from sewer drains, manholes, drainage courses and standing water What are the properties of a waste storage site?
Question What are the 2 most common waste disposal methods? Combustion and Sanitary Landfill
1. Classification of health-care institution waste It can be divided into two main categories: - Regular medical waste (waste generally everything else used in the facility. This might include administrative waste, paper, or food-waste from cafeterias) - Infectious waste Health-care institution solid waste
Health-care workers (particularly nurses) are at greatest risk of virus infections such as HIV/AIDS and hepatitis B and C, through injuries from contaminated sharps 2.Health Hazards
3. Sources a) Medical wastes b) Surgical and autopsy c) Laboratory wastes d) Infectious solid waste e) Domestic wastes f) Radioactive wastes
Management of health care institution Waste minimization, recycling, reuse Handling, storage and transportation of Health Care waste Treatment and disposal technologies for health-care facility waste
Public Policy and Waste Management The management of MSW used to be entirely under the control of local governments. In recent years,however, state and federal agencies have played an increasingly important role in waste management, partly through regulation and partly through encouragement and facilitation.
First attemp by Congress to address the problem was the Solid Waste Disposal Act of 1965. The Resource Recovery Act of 1970 gave jurisdiction over waste management, encourages the states to develop waste management program.
RESOURCE CONSERVAT İ ON AND RECOVERY ACT Management of hazardous waste in United States began in 1976 with passage of Resource Conservation and Recovery act (RCRA) – identification of hazardous wastes and their life cycles. Applies to solid, semisolid, liquid and gaseous hazardous wastes.
Comprehensive Environmental Response, Compensation, and Liability Act CERCLA – act defined policies and procedures for release of hazardous substances into the environment. Commonly known as Superfund, was enacted by Congress on December 11, 1980.
Improved and tightened standards for disposal and cleanup of hazardous waste(for example, requiring double liners, monitoring landfills) Banned land disposal of certain hazardous chemicals, including dioxins, polychlorinated biphenyls(PCBs), and most solvents. Initiated a timetable for phasing out disposal of all untreated liquid hazardous waste in landfills of surface impoundments. Increased the size of the Superfund. The fund was allocated about $8.5 billion in 1986. congress approved another $5.1 billion for fiscal year 1998, which almost doubled the Superfund budget. In 1986, Cercla was strengthened by amendments made the following changes:
The National Environmental Policy Act (NEPA) was passed in 1970 along with the Environmental Protection Agency (EPA). The main objective of these federal enactments was to assure that the environment be protected against both public and private actions that have resulted in costs or harms inflicted on the ecosystem.
The Hazardous and Solid Waste Amendments of 1984 gave the EPA greater responsability for setting solid-waste criteria for all hazordous-waste facilities.
Other Legistation Federal legistation has changed the ways in which real estate business is conducted. The Superfund Amendment and Reasuthorization Act(SARA) of 1986 permits a possible defense against such liability, provided the property owner has completed an environmental audit prior to the purchase of the property. SARA legistation also required that certain industries reort all releases of hazardous materials, and a list of companies releasing hazardous substances became public.
Establishing who is responsable for existing hazardous-waste problems. When necessary, assisting in or providing funding for cleanup at sites identified as having a hazardous-waste problem. Providing measures whereby people who suffer damages from the release of hazardous materials compensated. Improving the required standards for disposal and cleanup of hazardous waste. In 1990, the U.S. Congress reauthorized hazardous- wastecontrol legistation. Priorities include:
Industrialization and globalization have increased the quantity and quality of goods that are produced and moved around the world mainly through trade. This has led to an increased generation of waste since due to availability; items are discarded with no real attachment or need for repair.
E - waste
Population vs. Urbanization
Key Solid Waste Issues in Developping Countries Population growth in urban centers Lack of legistation and policies, long-term planning Inadequate storage Lack of proper disposal Use of inappropriate technology and equipment Insufficient knowledge of basicprinciples
Comparaison of Solid Waste Management by the Level of Income
Urban Waste Generation by Income Level
Waste Generation by Region AFR: African Countries SAR:Special Administrative Region MENA:Middle East & North Africa ECA:Europe & Central Asia LAC:Latin America Countries EAP:Eastern Partnership OECD:The Organisation for Economic Co-operation and Development
Waste Generation by Region
Regions with low- income countries tend to have low collection rates. South Asia and Africa are the lowest with 65% and 46% respectively. Not surprisingly, OECD countries tend to have the highest collection efficiency at 98%.
Question: Can you make a comment on the general overview on Turkey’s Waste Management Problem ? Responding to unlimited human needs on higher levels with the help of technology makes it inevitable for the environment and human health to be faced with serious threats as the natural resources are increasingly destroyed and each product manufactured is finally transformed into waste. In Turkey, waste management has been a subject of legal arrangements since 1930s and municipalities are assigned as the main implementation authority. According to TURKSTAT data for the year 2004, the quantity of solid waste collected by municipalities is 34 million tons annually.
The complete harmonization of the national legislation with EU Acquis and international standards and especially the new arrangements ensuring the implementation of the principles and policies coming from the existing arrangements are needed.
Thank you for listening...
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