E-Waste, Hemant Gaule,

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A review paper on electronic waste, where we have discussed the hazards and possible environmentally friendly treatment/recycling options of electronic waste.

Text of E-Waste, Hemant Gaule,

E-Waste Management: A Profit Making IndustryHemant Gaule, Anchal Gupta, and Arvind Kumar Mungray* Department of Chemical Engg. Sardar Vallabhbhai National Institute of Technology, Surat395007, India Abstract Over the past two decades, the volume of electrical and electronic waste has increased by less than half a million units annually in the mid-1980s to over twenty million units worldwide by 2007. People are upgrading their electronic devices more frequently than before. Not only is E-Waste being generated at an alarming rate, but it is being handled improperly widely, most of it being dumped or incinerated directly into the environment. The waste contains many valuable substances, some in larger concentrations than their own respective ores; but unfortunately these substances are being extracted by highly inappropriate methods, which result in liberation of many hazardous compounds. E-Waste contains elements that are poisonous carcinogens, and so improper disposal of the waste gives them a dangerous exposure to the environment, since most of these are also quite volatile. If appropriate means are employed to extract these substances, they can produce huge revenues. In other words, recycling is perhaps the most lucrative of all the management options for E-Waste. Creation of such a comprehensive recycling process will involve review of the entire life-cycle of the electronic gadget, right from the materials and processes employed to manufacture it, to its possible use after its rendered obsolete. For instance, the knowledge of who are the major producers of E-Waste to where it ends up, how it ends up there and how can it be handled, preferably, recycled after that. Key words: E-Waste; computers; hazards; management; disposal *(corresponding author) Tel.: +91-9904173019 E-mail address: akm@ched.svnit.ac.in; amungray@yahoo.com

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1. Introduction E-waste is a popular, informal name for discarded and end-of-life electronic / electrical products. Electronic waste includes computers, entertainment electronics, mobile phones and other items that have been discarded by their original users. While there is no generally accepted definition of electronic waste, in most cases electronic waste consists of electronic products that were used for data processing, telecommunications, or entertainment in private households and businesses that are now considered obsolete, broken, or irreparable. As new technologies and hardware replace the old ones, consumers get a wider choice of, better and relatively cheaper range of electronic goods to buy from. This generates huge amounts of E-Waste. The waste contains many potentially harmful substances, which may cause numerous harms to the environment. Unfortunately, despite of its hazardous content, the waste is treated in such a way that most of the hazardous constituents get easily exposed to the environment. This is mainly because most of the electronic circuits contain valuable elements like gold, platinum and copper, and that too in larger concentrations than their own respective ores which are simply stripped away from the waste and the residue is simply dumped or burned away. For many developed countries, handling the amount of E-Waste that they generate would be costlier than exporting it (sometimes illegally) to other developing/undeveloped countries, (like those of the Indian subcontinent, and Kenya etc.), where a workforce willing to work for low wages in such hazardous conditions is easily available. Moreover, most of this export is illegal. Despite its common classification as a waste, disposed electronics are a considerable category of secondary resource due to their significant suitability for direct reuse (for example, many fully functional computers and components are discarded during upgrades), refurbishing, and material recycling of its constituent raw materials. Reconceptualization of electronic waste as a resource thus preempts its potentially hazardous qualities. Considering all these aspects, the idea of an industry is suggested that efficiently collects and processes E-Waste will not only prevent the hazards that may be caused by improper dumping of E-Waste, but will also produce a whole lot of raw material and therefore, revenue. Creating such an industry will involve contributions of the government, the manufacturer and the consumer. This paper reviews the hazards and possible management options that may be used to cope up with E-Waste 1.1 Quantity of E-waste European studies estimate that the volume of E-waste is increasing by 3% - 5% per year, which is almost three times faster than the municipal waste stream is growing. Today, electronic waste likely comprises more than 5% of all municipal solid waste; thats more than disposable diapers or beverage containers, and about the same amount as all plastic packaging [1]. Taking computers for instance, newer software rendering the old ones obsolete (software pushing), and cheaper, attractive hardware cause rapid obsolescence of computers. In 1994, it was estimated that approximately 20 million

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personal computers (about 7 million tons) became obsolete. By 2004, this figure was to increase to over 100 million personal computers. Cumulatively, about 500 million PCs reached the end of their service lives between 1994 and 2003. 500 million PCs contain approximately 2,872,000 tonnes of plastics, 718,000 tonnes of lead, 1363 tonnes of cadmium and 287 tonnes of mercury [2]. This fast growing waste stream is accelerating because the global market for PCs is far from saturation and the average lifespan of a PC is decreasing rapidly for instance for CPUs from 46 years in 1997 to 2 years in 2005 [3]. As in the case of India, it was estimated that obsolete personal computers were around 2.25 million units in 2005, which are expected to touch a figure of 8 million obsolete units by the year 2010 at an average annual growth rate of approximately 51% Considering an average weight of 27.18 kg for a desktop/personal computer approximately 61,155 tonnes of obsolete computer waste would have been generated in India in 2005, which would increase to about 217,440 tonnes by the year 2010 at the projected growth rate [4]. Similarly, for US, it was estimated that 20 million computers became obsolete in 1998, and the overall E-waste volume was estimated at 5 to 7 million tonnes. The figures are projected to be higher today and rapidly growing. A 1999 study conducted by Stanford Resources, Inc. for the National Safety Council projected that in 2001, more than 41 million personal computers would become obsolete in the U.S. Analysts estimate that in California alone more than 6,000 computers become obsolete every day. In Oregon and Washington, it is estimated that 1,600 computers become obsolete each day [5]. To make matters worse, solid waste agencies and recyclers are anticipating a major increase in the volume of computer and TV monitors discarded in the next 5 years. As cathode-ray tube (CRT) monitors currently in use will be replaced by smaller, and more desirable liquid crystal display (LCD) screens, this could mean massive dumping of CRT monitors at an even higher rate. This leap in technology is also expected to lead to a significant increase in television disposal. So is the case with every other category of EWaste, which indicates that it is very likely that the quantity of this waste will only increase. 1.2 Composition of E-waste Eectronic waste contains the following elements [6]: Elements in bulk: Tin, Copper, Silicon, Carbon, Iron and Aluminum, Elements in small amounts: Cadmium and Mercury, Elements in trace amounts: Germanium, Gallium, Barium, Nickel, Tantalum, Indium, Vanadium, Terbium, Beryllium, Gold, Europium, Titanium, Ruthenium, Cobalt, Palladium, Manganese, Silver, Antimony, Bismuth, Selenium, Niobium, Yttrium, Rhodium, Platinum, Arsenic, Lithium, Boron, Americium List of examples of devices containing these elements

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Almost all electronics contain lead & tin (as solder) and copper (as wire & PCB tracks), though the use of lead-free solder is now spreading rapidly [6]. Some of these substances and the components where they are found are described in Table 1. Recently the Swiss ordinance has been amended (June 2004) to match the EU Directives definition of the ten categories listed in Table 2, Categories 14 account for almost 95% of the E-waste generated (Fig. 1). According to the definitions in the Directive 2002/96/EC of the European Parliament and of the Council (January 2003) on Waste Electrical and Electronic Equipment [7], (WEEE/E-waste) consists of the ten categories listed in Table 2. This categorization seems to be in the process of becoming a widely accepted standard. The Swiss Ordinance on the Return, the Taking Back and the Disposal of Electrical and Electronic Equipment (ORDEE) of 1998 differentiates between the following categories of E-waste. Electronic appliances for entertainment; Appliances forming part of office, communication and information technology; Household appliances Electronic components of the (above) appliances Fig. 2 categorizes the waste by the types of materials in it. Metals, as may be expected, form the majority of it. A study by the European Topic Center on Resource and E-Waste Management indicates that iron and steel form almost the half of the metals present in E-Waste, though theyre not at hazardous as many other metals present in it. Fig. 3 further shows the fraction of individual categories of materials present in E-Waste. 1.3 Sources of E-waste Developed countries like US, a few West Asian and European countries, produce enormous amounts of E-Waste every year. Most of this is exported to developing nations like India, China, Pakistan, Malaysia etc. This is because those countries produce so much E-Waste themselves, that exporting it would be much cheaper than managing it themselves. Also, these developing natio