viable e waste treatment - incineration vs non incineration

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Electronic Waste Treatment Incineration vs Non Incineration

Viable Electronic Waste Treatment Incineration vs Non Incineration PRESENTED BY Rohit Shinde Bhushan Shinde Rohan Thomre Deepak Awhad

ContentWhat is Electronic Waste?How these become E-WasteGeneration of E-waste by Countries Why E-Waste a Problem?Constituents of E-Waste E-Waste Processing stepsMethods for E-Waste treatmentIncineration Process Description, Types, Advantage and DisadvantageNon-Incineration Process Description, Types, Advantage and Disadvantage Did you know?Conclusion

Todays Electronic Gadgets,Tomorrows Electronic Waste

What is Electronic Waste?It is the term used to describe old, end-of-life or discarded appliances using electricity and batteryComputers, Cell Phones, televisions, VCRs, stereos, copiers, and fax machinesare common electronic products

How these become E-WasteTrends Changes and advancement in TechnologyChanges in fashion, style and statusChanging configuration Attractive offers from manufacturers Small life of equipment Effects of TrendsCell phone upgradesDigital TV conversionCant Change battery in your IPodBuy one and get one free offers Disposable printers

How these become E-Waste?1.6 billionCell phones manufactured in 2012. Electronics are packed with toxic chemicalsarsenic, lead, and poly-brominated flame retardants.18 monthsThats how short the average American keeps a cell phone60% wastedMost of our e-waste ends up in landfillsboth at home and in the developing worldwhere toxic metals leach into the environment.30% lostEven when recycled, a significant amount of electronic material cannot be recovered.

Generation of E-waste by Countries

Why E-Waste a Problem?Theelectronic waste problemis huge: More than 20 million tons ofe-wasteare produced every year globally Composed of Hazardous MaterialsProducts are quickly obsolete and discarded Electronic products are difficult to Recycle

Constituents of E-WasteHazardous materials Mercury Even low doses of mercury can be toxic and may cause kidney and brain damage.Lead Humans are very familiar with the negative health effects of lead, including brain damage, particularly in children.Brominated Flame Retardants (BFRs) BFRs are known to negatively affect hormonal functions that are essential for normal development.Cadmium Cadmium has been shown to cause cancer, and when it accumulates within the body, it may result in kidney damageValuable materialsGermanium, Indium, Gallium Are needed in semi conductor devices.Tin For Soldering and coating.Copper 110k 130k kg/ton in cell phonesSilver 20 kg/ton in pin transistors Gold - 300-350 grams/ton in cell phones

E-Waste Processing steps

Methods for E-Waste Treatment3 Rs method: Reduce, Reuse and Recycle (This focuses on extracting maximum benefits and generating minimum amount of waste)Incineration Techniques: Rotary kilnsFluidized bed unitsLiquid injection unitsFixed hearth unitsNon-Incineration Techniques:LandfillAcid bath

IncinerationThis is a controlled way of disposing off the e-waste and it involves combustion of electronic waste at high temperature in specially designed incineratorsIncineration and other high-temperature waste treatment systems are described as "thermal treatment".Incineration of waste materials converts the waste intoash,flue gas, and heat. The ash is mostly formed by theinorganicconstituents of the waste, and may take the form of solid lumps orparticulatescarried by the flue gas.The flue gases must be cleaned of gaseous and particulate pollutants before they are dispersed into theatmosphere. In some cases, the heat generated by incineration can be used to generateelectric power

Process Block Diagram

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Process Description1. Waste Storage : Sufficient amount of waste is stored to run the incinerator which can be also called as waste storage site.2. Combustion chamber : This is the key part of the system where the burning actually takes place. There is a controllable supply of a secondary fuel such as natural gas. The amount of secondary fuel supplied is adjusted to ensure the required temperature is reached. 3. Energy Extraction : The hot exhaust or flue gases are passed through heat exchangers and the heat removed is used to raise steam. 4. Scrubber : It is used to clean the flue gases.5. Flue Gas Monitoring. Finally a thorough and continuous analysis of the exhaust is made to ensure that amounts of harmful substances released are below the permitted levels.

Types of IncinerationRotary kilnsFluidized bed unitsLiquid injection unitsFixed hearth units

Rotary kilns

Rotary kilnsThe most common combustion technology in hazardous waste incineration is the rotary kiln. Facilities range in size from 30,000 to 100,000 tons/year throughput. The RKI is a chemical reactor especially designed to burn solids, usually wastes that contaminate adsorbents (such as fuller's earth soaked with crude oil from an oil spill, or soil contaminated by liquids or solids in a landfill).Although rotary kilns are not specifically designed to burn gases, they are used for that purpose in chemical manufacturing plants where advantage can be taken of pollution control equipment associated with a rotary kiln burning other waste.The incineration of waste materials in a rotary kiln is an extremely complex process involving physical movement of solids, liquids, and gases, in addition to chemical reactions.

Rotary kilnsIn Rotary kilns solid, sludge, containerized or pump able waste is introduced at the upper end of the inclined drum. Temperatures in the kiln usually range between 850 and 13000C. The slow rotation of the drum allows a residence time of 30-90 minutes.The secondary combustion chamber following the kiln completes the oxidation of the combustion gases. Liquid wastes and/or auxiliary fuels may be injected here along with secondary air to maintain a minimum residence time of two seconds and temperatures in the range of 900-13000C, effectively destroying any remaining organic compounds.

Advantages of IncinerationRequires minimum land Can be operated in any weather Produces stable odor free residueRefuse volume is reduced by half

Disadvantages of Incineration Expensive to build and operateHigh energy requirement Requires skilled personnel and continuous maintenance Emission of harmful gasesEmission of cadmium and mercury

Non-Incineration Techniques Landfill

Acid bath

Landfill TechniqueThis is the most common methodology of e-waste disposalLandfills are often the most cost-efficient way to dispose of waste, especially in countries like the United States with large open spacesHowever, landfill is not an environmentally sound process for disposing off the e-waste as toxic substances like cadmium, lead and mercury are released inside the soil and ground water

Trench Method for LandfillSoil is excavated and trenches are made for burying the e-waste in itAn impervious liner is made of clay or plastic with a leachate basin for collection and transferring the e-waste to the treatment plant

Advantages and DisadvantagesAdvantages

It is inexpensiveThe used piece of land can be reused for the other community purposesLandfill gas can be upgraded to natural gas.

Disadvantages

Completed landfill areas can settle and requires maintenanceE-waste dispose toxic substances like cadmium, lead and mercury released inside the soil and ground water

Acid Bath MethodAcid bath involves soaking of the electronic circuits in the powerful sulphuric, hydrochloric or nitric acid solutions that free the metals from the electronic pathways

The recovered metal is used in the manufacturing of other products while the hazardous acid waste finds its ways in the local water sources

Acid baths also used to extraction of Gold and Silver.

Acid Bath ProcessAcid bath method is used to extract metals i.e. CopperHere the circuit board is submerged in to Sulfuric acid for about 12 hours to dissolve Copper. Then solution is boiled, precipitated Copper Sulfate is taken and remaining solution is added with scraped particles, subsequently Copper smudges are removed

Advantages and DisadvantagesAdvantages

Cheapest cleaning method availableLow manpower and space requiredDisadvantages

Acid recovery systems are expensiveSolvents used in the method are flammable so greater handling riskDue to more corrosive towards metal, high maintainance cost

Did you know?Mobile phone have a lifecycle of less than two years in developed countriesThe E waste generated is 3.16 million tons in the U.S.The United States and China are the world's biggest producers of electronic wasteA recent United Nations study found the U.S. is the worlds biggest producer of electronic waste, more than one million tons ahead of ChinaBy 2017, the volume of discarded e-products worldwide is expected to be 33 per cent higher than in 2012 and weigh the equivalent of eight of the Great Pyramids of Egypt

Did you know?2050 million tons of e-Waste are generated worldwide every year68% of US Consumers stockpile electronicsE-Waste comprises 2% of America's trash in landfills and 70% of overall toxic waste300 million computers and 1 BILLION cell phones are put into production each yearThe Environmental Protection Agency estimates that only 15-20% of e-waste is recycled, the rest of these electronics go directly into landfills and incineratorsApproximately 80% of e-Waste in the U.S. is exported to Asia

ConclusionProbably many of us was not that much aware of E waste before this presentation. Like the other pollutions E waste is also a major present and future issue for our planet.From all the facts, numbers, causes and eff

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