Monday, October 14, 2019
Methods Of Waste Management And Recycling Environmental Sciences Essay
Methods Of Waste Management And Recycling Environmental Sciences Essay Waste management means collecting, transporting, processing, recycling and monitoring of the waste materials. The term waste management generally relates to those materials which are produced by human activity and is usually undertaken to reduce the effect of these activities on their health and environment. Waste management is also useful to recover useful resources from the waste. Waste management involves all solid, liquid and gaseous or radioactive substances which are managed with different methods and expertise is required for each of them. Waste management practices are different for different countries of the world be it developed or developing nations. The management is different for urban and rural areas, for residential and industrial waste producers. Management of residential and institutional waste in cities and metros is done by the local government authorities or what we call as Municipal Corporation, while management of non-hazardous commercial and industrial waste is done by the generator of such waste. Solid waste Management Plasma gasification Plasma is a highly ionized or electrically charged gas. An example in nature is lightning, capable of producing temperatures exceeding 12,600Ã Ã °F (6,980Ã Ã °C). A gasifier vessel utilizes proprietary plasma torches operating at +10,000Ã Ã °F (5,540Ã Ã °C) (the surface temperature of the Sun) in order to create a gasification zone of up to 3,000Ã Ã °F (1,650Ã Ã °C) to convert solid or liquid wastes into a sun gas. When municipal solid waste is subjected to this intense heat within the vessel, the wastes molecular bonds break down into elemental components. The process results in elemental destruction of waste and hazardous materials According to the U.S. Environmental Protection Agency, the U.S. generated 250 million tons of waste in 2008 alone, and this number continues to rise. About 54% of this trash (135,000,000Ã short tons (122,000,000 t)) ends up in landfills and is consuming land at a rate of nearly 3,500Ã acres (1,400 ha) per year. In fact, landfilling is currently the number one method of waste disposal in the US. Some states no longer have capacity at permitted landfills and export their waste to other states. Plasma gasification offers states new opportunities for waste disposal, and more importantly for renewable power generation in an environmentally sustainable manner. Landfill Disposing of waste in a landfill involves burying the waste, and this remains a common practice in most countries. Landfills were often established in abandoned or unused quarries, mining voids or borrow pits. A properly designed and well-managed landfill can be a hygienic and relatively inexpensive method of disposing of waste materials. Older, poorly designed or poorly managed landfills can create a number of adverse environmental impacts such as wind-blown litter, attraction of vermin, and generation of liquid leach ate. Another common byproduct of landfills is gas (mostly composed of methane and carbon dioxide), which is produced as organic waste breaks down anaerobic ally. This gas can create odour problems, kill surface vegetation, and is a greenhouse gas. Design characteristics of a modern landfill include methods to contain leachate such as clay or plastic lining material. Deposited waste is normally compacted to increase its density and stability, and covered to prevent attr acting vermin (such as mice or rats). Many landfills also have landfill gas extraction systems installed to extract the landfill gas. Gas is pumped out of the landfill using perforated pipes and flared off or burnt in a gas engine to generate electricity. Water Treatment Water treatment means all those processes which are used to make water acceptable for a desired end-use. These include use of water for drinking, medical, industrial processes and many other uses. The goal of all such water treatment is to remove the contaminants present in the water or reduce the concentration of contaminants so that the water becomes fit for consumption. One meaning to it is returning water to its natural environment without adversely impacting the ecology. The processes for treating water for drinking purpose can be solids separation by using physical processes such as settling and filtration, and chemical processes such as disinfection and coagulation and Biological processes if required. In general the process includes: Pre-chlorination for algae control and arresting any biological growth Aeration along with pre-chlorination for removal of dissolved iron and manganese Coagulation for flocculation Coagulant aids, also known as polyelectrolyte to improve coagulation and for thicker floc formation Sedimentation for solids separation, that is, removal of suspended solids trapped in the floc Filtration removing particles from water Desalination Process of removing salt from the water Disinfection for killing bacteria. There is no unique solution for any type of water. Also, it is difficult to standardize the solution in the form of processes for water from different sources. Treatability studies for each source of water in different seasons need to be carried out to arrive at most appropriate processes. Sewage treatment is the process which removes the majority of the contamination from wastewater or sewage and produces both a liquid effluent suitable for disposal to the natural environment. To be effective, sewage must be conveyed to a treatment plant by appropriate pipes and infrastructure and the process itself must be subject to regulation and controls. E-waste management Electronic waste is defined as all the secondary computers, entertainment devices, mobile phones, all other items like television, refrigerators, whether they are sold or donated or discarded by their original owners or users. In simple terms all those items mentioned above which are either dumped or disposed or discarded by their buyers rather than recycling and reusing them is called E-Waste. A major portion of this waste is generated through products like personal computers, laptops etc. According to recent estimates about 50 million tons of E-waste is produced each year around the globe. The USA alone discards 30 million computers each year and nearly 100 million phones are discarded in Europe each year. The reasons for these huge figures are that there are the rapid changes in technology, low cost of the product initially which encourages people to buy new instead of repairing and reusing and also the cost of modifying the features is much more than the original cost. Moreover t he electronic goods today are made in such a way that they follow something called as planned obsolescence which means they get obsolete with the passage of time. Electronic waste processing first involves dismantling the equipment or the electronic item into various parts i.e. metal frames, circuit boards, power supplies, plastics etc. and this is often done manually. The advantage of this process is that humans have the ability to recognize and save those parts which are working and are repairable which includes chips, RAM, transistors etc. The disadvantage of this process is that the labour might often be expensive in those countries which have high health and safety standards. An alternative to this is called bulk system; wherein a hopper conveys material meant for shredding into a very sophisticated mechanical separator which has screening and grinding machines to separate the constituents of metal and plastic fractions. These plastic fractions are then sold to plastics recycle rs or smelters. Emissions are caught by the scrubbers and screens. To separate glass, plastic, harmful and unharmful metals; magnets and eddy currents are used. Copper, gold silver, tin etc. valuable metals are sold to smelters for recycling purpose. Hazardous smoke and gases are captured, and then treated to remove the environmental threat. An ideal electronic waste recycling plant is one which combines dismantling for recovery of its components with increased cost-effectiveness of processing of bulk electronic waste. Reuse is an alternative option to recycling because it extends the life of the device. Recycling Reduce, Reuse, Recycle are known as the 3R of the waste hierarchy. Recycling involves processing used materials into new products to prevent waste of potentially useful materials, reduce the consumption of fresh raw materials, reduce energy usage, reduce air pollution and water pollution by reducing the need for conventional waste disposal, and lower greenhouse gas emissions as compared to virgin production Recycling is a key component of modern waste reduction and is the third component of Recyclable materials include many kinds of glass, paper, metal, plastic, textiles, and electronics. Although similar in effect, the composting or other reuse of biodegradable waste such as food or garden waste is not typically considered recycling. Materials to be recycled are either brought to a collection center or picked up from the curbside, then sorted, cleaned, and reprocessed into new materials bound for manufacturing. Recycling Saves money, energy, trees the planet Earth. In a strict sense, recycling of a material would produce a fresh supply of the same material-for example; used office paper would be converted into new office paper, or used foamed polystyrene into new polystyrene. However, this is often difficult or too expensive (compared with producing the same product from raw materials or other sources), so recycling of many products or materials involve their reuse in producing different materials (e.g., paperboard) instead. Another form of recycling is the salvage of certain materials from complex products, either due to their intrinsic value (e.g., lead from car batteries, or gold from computer components), or due to their hazardous nature. Critics dispute the net economic and environmental benefits of recycling over its costs, and suggest that proponents of recycling often make matters worse and suffer from confirmation bias. Specifically, critics argue that the costs and energy used in collection and transportation detract from (and outweig h) the costs and energy saved in the production process; also that the jobs produced by the recycling industry can be a poor trade for the jobs lost in logging, mining, and other industries associated with virgin production; and that materials such as paper pulp can only be recycled a few times before material degradation prevents further recycling. Proponents of recycling dispute each of these claims, and the validity of arguments from both sides has led to enduring controversy Recent developments: Jamshedpur Utilities Services Company (Jusco), which is a fully owned subsidiary of Tata Steel, recently bagged the Municipal Solid Waste management contract for Mysore city from the Mysore City Corporation and Municipal Solid Waste (MSW) management contract under the Kolkata metropolitan area for six municipalities. Under the project Jusco will construct 5transfer stations and 6 compost plants in the municipalities of Champdani, Baidyabati, Serampore, Rishra, Konnagar and Uttarapara-Kotrung which fall under Kolkata Metropolitan Development Authority (KMDA). The Rs 39 crore projects will be funded by Japan International Cooperation Agency (JICA). Jusco offers integrated solutions to municipal waste management which comprises of waste transfer, transfer station management, composting, engineered structured landfills, integrated waste recycling and reclamation, recycling of municipal and specialized wastes, etc. The utilities major also bagged the TPM Excellence A ward -2008 instituted by the Japan Institute of Plant Maintenance (JIPM) and has several other national and international awards like National Urban Water Awards (NUWA) in the citizen services governance category for 2009.
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