logging in or signing up Landfills and its Principles mukulnryn Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 1614 Category: Education License: All Rights Reserved Like it (0) Dislike it (3) Added: September 18, 2009 This Presentation is Public Favorites: 1 Presentation Description It tells about the waste management using landfills and the construction of a landfill. Comments Posting comment... By: historykillers (15 month(s) ago) weird Saving..... Post Reply Close Saving..... Edit Comment Close By: historykillers (15 month(s) ago) weird Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Slide 1: ERG C22 ASSIGNMENT Slide 2: LANDFILLS AND ITS PRINCIPLE Slide 3: Presented By : MUKUL NARAYAN BTE 07 026 Slide 4: MUKUL NARAYAN IIIrd YEAR AGRICULTURAL ENGINEERING COLLEGE AND RESEARCH INSTITUTE LALGUDI TRICHY TAMIL NADU INDIA PH : 09751092282 EMAIL : mukulnryn@gmail.com Slide 10: What is a Landfill? A secure landfill is a carefully engineered depression in the ground (or built on top of the ground) into which wastes are put. Slide 11: The aim is to avoid any hydraulic connection between the wastes and the surrounding environment, particularly groundwater. Basically, a landfill is a bathtub in the ground; a double-lined landfill is one bathtub inside another. Bathtubs leak two ways: out the bottom or over the top. Its AIM? Slide 12: What are Landfills made of ? Landfills are lined with clay or plastic lining to prevent liquid waste called leachate, from escaping in to the soil. As certain parts of landfills are closed, pipes are installed to help avoid the escaping gases. These gases can also be used to create electricity. Slide 13: and around the landfill to monitor groundwater quality and to detect any contamination. These safety measures keep ground water, which is the main source of drinking water in many communities, clean and pure. A network of drains collects the leachate and pumps it to the surface where it can be treated. Ground wells are also drilled into Slide 14: At the end of each day’s activities, workers spread a layer of earth ‘called the daily cover’ over the waste to reduce odour and control vermin. The workers fill and cap each cell with a layer of clay and earth, and then seed the area with native grasses. Slide 16: When a landfill is full, workers seal and cover the landfill with a final cap of clay and dirt. Workers continue to monitor the ground wells for years after a landfill is closed to keep tabs on the quality of groundwater on and around the site. Slide 17: Old landfill sites can be landscaped to blend in with their surroundings, or specially developed to provide an asset to a community. Closed landfills can be turned into anything from parks to parking lots, from golf courses to ski slopes. Building homes and businesses on these sites is generally not permitted, though, since it can take many years for the ground to settle. What do we do with the old Landfill sites?? Slide 19: The Composition of a Landfill There are four critical elements in a secure landfill: a bottom liner, a leachate collection system, a cover, and the natural hydrogeologic setting. The natural setting can be selected to minimize the possibility of wastes escaping to groundwater beneath a landfill. The three other elements must be engineered. Each of these elements is critical to success. Slide 21: 1. Bottom Liner It may be one or more layers of clay or a synthetic flexible membrane (or a combination of these). The liner effectively creates a bathtub in the ground. If the bottom liner fails, wastes will migrate directly into the environment. There are three types of liners: clay, plastic, and composite. Slide 22: Natural clay is often fractured and cracked. A mechanism called diffusion will move organic chemicals like benzene through a three-foot thick clay landfill liner in approximately five years. Some chemicals can degrade clay. So, it is not widely used… Slide 23: The very best landfill liners today are made of a tough plastic film called high density polyethylene (HDPE). BUT… A number of household chemicals will degrade HDPE, permeating it (passing though it), making it lose its strength, softening it, or making it become brittle and crack. Slide 24: A Composite liner is a single liner made of two parts, a plastic liner and compacted soil (usually clay soil). BUT.. Reports show that all plastic liners (also called Flexible Membrane Liners, or FMLs) will have some leaks. It is important to realize that all materials used as liners are at least slightly permeable to liquids or gases and a certain amount of permeation through liners should be expected. Additional leakage results from defects such as cracks, holes, and faulty seams. Slide 25: 2. Leachate collection system Leachate is a water that gets badly contaminated by contacting wastes. It seeps to the bottom of a landfill and is collected by a system of pipes. The bottom of the landfill is sloped; pipes laid along the bottom capture contaminated water as they accumulate. The pumped leachate is treated at a wastewater treatment plant. Slide 26: Leachate collection systems can clog up in less than a decade. They fail in several known ways: 1) They clog up from silt or mud; 2) They can clog up because of growth of microorganisms in the pipes; 3) They can clog up because of a chemical reaction leading to the precipitation of minerals in the pipes; or 4) The pipes become weakened by chemical attack (acids, solvents, oxidizing agents, or corrosion) and may then be crushed by the tons of garbage piled on them. Slide 27: 3. Cover A cover or cap is an umbrella over the landfill to prevent leachate formation. It will generally consist of several sloped layers to prevent rain from intruding. If the cover is not maintained, rain will enter the landfill resulting in build-up of leachate to the point where the bathtub overflows its sides and wastes enter the environment. Slide 28: You want the geology to do two contradictory things for you. To prevent the wastes from escaping, you want rocks as tight (waterproof) as possible. Yet if leakage occurs, you want the geology to be as simple as possible so you can easily predict where the wastes will go. Then you can put down wells and capture the escaped wastes by pumping. 4. The natural hydrogeologic setting Slide 30: The Landfill Energy Methane gas get produced from the waste degradation in landfills. The methane can be used as an energy source. Landfills can collect the methane gas, treat it, and then sell it as a commercial fuel; or they can burn it to generate steam and electricity. Slide 31: Impacts of Landfill operations Fatal accidents (e.g., scavengers buried under waste piles) Infrastructure damage (e.g., damage to access roads by heavy vehicles) Pollution of the local environment (such as contamination of groundwater and/or aquifers by leakage and residual soil contamination during landfill usage, as well as after landfill closure). Slide 32: 3. Off gassing of methane generated by decaying organic wastes (methane is a greenhouse gas many times more potent than carbon dioxide, and can itself be a danger to inhabitants of an area) 4. Harbouring of disease vectors such as rats and flies, particularly from improperly operated landfills, which are common in Third-world countries; injuries to wildlife 5. Simple nuisance problems (e.g., dust, odour, vermin, or noise pollution). Slide 33: Thank You You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
Landfills and its Principles mukulnryn Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 1614 Category: Education License: All Rights Reserved Like it (0) Dislike it (3) Added: September 18, 2009 This Presentation is Public Favorites: 1 Presentation Description It tells about the waste management using landfills and the construction of a landfill. Comments Posting comment... By: historykillers (15 month(s) ago) weird Saving..... Post Reply Close Saving..... Edit Comment Close By: historykillers (15 month(s) ago) weird Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Slide 1: ERG C22 ASSIGNMENT Slide 2: LANDFILLS AND ITS PRINCIPLE Slide 3: Presented By : MUKUL NARAYAN BTE 07 026 Slide 4: MUKUL NARAYAN IIIrd YEAR AGRICULTURAL ENGINEERING COLLEGE AND RESEARCH INSTITUTE LALGUDI TRICHY TAMIL NADU INDIA PH : 09751092282 EMAIL : mukulnryn@gmail.com Slide 10: What is a Landfill? A secure landfill is a carefully engineered depression in the ground (or built on top of the ground) into which wastes are put. Slide 11: The aim is to avoid any hydraulic connection between the wastes and the surrounding environment, particularly groundwater. Basically, a landfill is a bathtub in the ground; a double-lined landfill is one bathtub inside another. Bathtubs leak two ways: out the bottom or over the top. Its AIM? Slide 12: What are Landfills made of ? Landfills are lined with clay or plastic lining to prevent liquid waste called leachate, from escaping in to the soil. As certain parts of landfills are closed, pipes are installed to help avoid the escaping gases. These gases can also be used to create electricity. Slide 13: and around the landfill to monitor groundwater quality and to detect any contamination. These safety measures keep ground water, which is the main source of drinking water in many communities, clean and pure. A network of drains collects the leachate and pumps it to the surface where it can be treated. Ground wells are also drilled into Slide 14: At the end of each day’s activities, workers spread a layer of earth ‘called the daily cover’ over the waste to reduce odour and control vermin. The workers fill and cap each cell with a layer of clay and earth, and then seed the area with native grasses. Slide 16: When a landfill is full, workers seal and cover the landfill with a final cap of clay and dirt. Workers continue to monitor the ground wells for years after a landfill is closed to keep tabs on the quality of groundwater on and around the site. Slide 17: Old landfill sites can be landscaped to blend in with their surroundings, or specially developed to provide an asset to a community. Closed landfills can be turned into anything from parks to parking lots, from golf courses to ski slopes. Building homes and businesses on these sites is generally not permitted, though, since it can take many years for the ground to settle. What do we do with the old Landfill sites?? Slide 19: The Composition of a Landfill There are four critical elements in a secure landfill: a bottom liner, a leachate collection system, a cover, and the natural hydrogeologic setting. The natural setting can be selected to minimize the possibility of wastes escaping to groundwater beneath a landfill. The three other elements must be engineered. Each of these elements is critical to success. Slide 21: 1. Bottom Liner It may be one or more layers of clay or a synthetic flexible membrane (or a combination of these). The liner effectively creates a bathtub in the ground. If the bottom liner fails, wastes will migrate directly into the environment. There are three types of liners: clay, plastic, and composite. Slide 22: Natural clay is often fractured and cracked. A mechanism called diffusion will move organic chemicals like benzene through a three-foot thick clay landfill liner in approximately five years. Some chemicals can degrade clay. So, it is not widely used… Slide 23: The very best landfill liners today are made of a tough plastic film called high density polyethylene (HDPE). BUT… A number of household chemicals will degrade HDPE, permeating it (passing though it), making it lose its strength, softening it, or making it become brittle and crack. Slide 24: A Composite liner is a single liner made of two parts, a plastic liner and compacted soil (usually clay soil). BUT.. Reports show that all plastic liners (also called Flexible Membrane Liners, or FMLs) will have some leaks. It is important to realize that all materials used as liners are at least slightly permeable to liquids or gases and a certain amount of permeation through liners should be expected. Additional leakage results from defects such as cracks, holes, and faulty seams. Slide 25: 2. Leachate collection system Leachate is a water that gets badly contaminated by contacting wastes. It seeps to the bottom of a landfill and is collected by a system of pipes. The bottom of the landfill is sloped; pipes laid along the bottom capture contaminated water as they accumulate. The pumped leachate is treated at a wastewater treatment plant. Slide 26: Leachate collection systems can clog up in less than a decade. They fail in several known ways: 1) They clog up from silt or mud; 2) They can clog up because of growth of microorganisms in the pipes; 3) They can clog up because of a chemical reaction leading to the precipitation of minerals in the pipes; or 4) The pipes become weakened by chemical attack (acids, solvents, oxidizing agents, or corrosion) and may then be crushed by the tons of garbage piled on them. Slide 27: 3. Cover A cover or cap is an umbrella over the landfill to prevent leachate formation. It will generally consist of several sloped layers to prevent rain from intruding. If the cover is not maintained, rain will enter the landfill resulting in build-up of leachate to the point where the bathtub overflows its sides and wastes enter the environment. Slide 28: You want the geology to do two contradictory things for you. To prevent the wastes from escaping, you want rocks as tight (waterproof) as possible. Yet if leakage occurs, you want the geology to be as simple as possible so you can easily predict where the wastes will go. Then you can put down wells and capture the escaped wastes by pumping. 4. The natural hydrogeologic setting Slide 30: The Landfill Energy Methane gas get produced from the waste degradation in landfills. The methane can be used as an energy source. Landfills can collect the methane gas, treat it, and then sell it as a commercial fuel; or they can burn it to generate steam and electricity. Slide 31: Impacts of Landfill operations Fatal accidents (e.g., scavengers buried under waste piles) Infrastructure damage (e.g., damage to access roads by heavy vehicles) Pollution of the local environment (such as contamination of groundwater and/or aquifers by leakage and residual soil contamination during landfill usage, as well as after landfill closure). Slide 32: 3. Off gassing of methane generated by decaying organic wastes (methane is a greenhouse gas many times more potent than carbon dioxide, and can itself be a danger to inhabitants of an area) 4. Harbouring of disease vectors such as rats and flies, particularly from improperly operated landfills, which are common in Third-world countries; injuries to wildlife 5. Simple nuisance problems (e.g., dust, odour, vermin, or noise pollution). Slide 33: Thank You