22 April 2009
Author: Charalambos SivridisElectronic waste and recycling
What is e-waste?
"Electronic waste" may be defined as all old, not in use, or broken electronics and electrical appliances. Loads of electrical and electronic devices are dumped every day uncontrolled in landfills polluting fields and the underground water. We have to know that electronic waste is highly toxic and full with carcinogenic substances and in a heavily polluted environment such as ours there has to be some kind of guidelines in order to prevent or minimize further pollution.
The only logical solution is recycling, and that means processed properly is special e-waste handling/recycling factories. According to Mr. Tonetti (environmental scientist for US EPA), American markets for e-waste are primarily export. "There is a strong demand for raw materials in developing countries, both for-profit and non-profit markets. There are no smelters for the recovery of copper and other precious metals located in the U.S., nor are there any cathode ray tube (CRT) glass furnaces here; and plastic recycling markets are also almost all overseas," he said also "As collection of e-waste in the U.S. increases, exports will also increase."
Increased regulation from the US EPA and the EU for e-waste resulted higher disposal cost. The main solution found is to export e-waste to less ?strict? developing nations for recycling. Yet even while it presents challenges in regard to its safe handling and disposal, e-waste also represents a potentially rich source of secondary raw materials. The worldwide market for e-waste is growing by almost 9% per year, from $7.2 billion in 2004 to a projected $11 billion in 2009 as reported from International Resource Group (www.irgltd.com). Possibly you may think ok so what if my old T.V. or computer is exported and recycled to another nation? Ba`sically very cheap labor and high raw materials leads to a transfer of pollution-generating activities to other countries (like China, Malaysia, India and various African countries) but the main problem is that electronic waste is being sent to these countries for processing and sometimes ends up in illegal e-waste landfills or in doubtful recycling facilities. According to www.environmentalhealthnews.org Chinese factory workers who dismantle computers and other electronic equipment waste (E-waste) are chronically exposed to high levels of dangerous chemicals that damage their DNA and are known to cause a variety of health ills. A study (http://www.environmentalhealthnews.org/ehs/newscience/e-waste-chemicals-change-workers-dna) highlighted the high exposures and health hazards associated with handling E-waste under less controlled conditions. Workers had more damaged DNA than non-factory workers; 5-times more altered DNA after work than before and higher levels of some chemicals than reported in U.S. workers. Dust samples from the factories contained orders of magnitude higher levels of chemicals than have been reported in other worldwide studies. Many adverse health effects have been linked to the pollutants and this type of DNA damage can lead to cancer and premature aging.
The videos will help you to understand a little bit how your old electronic devices are recycled...
EU RoHS and WEEE directives
In 2003 the EU adopted two new directives on the restriction of the use of hazardous substances and recycling of electrical and electronic devices.
The name of the first directive (2002/95/EC) was Restriction of Hazardous Substances Directive (or if you like RoHS). The main idea behind this directive is to minimize the use of specific hazardous materials from electrical and electronic devices and in a way to make the devices environmental friendly and easier for recycling. The materials affected by this directive are heavy metals such as lead, mercury, cadmium, and chromium and flame retardants such as polybrominated biphenyls (PBB) or polybrominated diphenyl ethers (PBDE). RoHS applies to all electrical and electronic appliances produced or imported in the EU (although there are few exemptions). RoHS took effect on 2006 and it became law in each member state. RoHS does not require any specific logo, however many manufacturers have adopted their own RoHS logos.
Some RoHS logos
The second directive (2002/96/EC) was the Waste Electrical and Electronic Equipment Directive (WEEE). The legislation provides for the creation of collection schemes where consumers return their used e-waste free of charge. The objective of these schemes is to increase the recycling and/or re-use of such products. The EU Commission proposes to set mandatory collection targets equal to 65% of the average weight of electrical and electronic equipment placed on the market over the two previous years in each Member State.
US EPA Plug-in to eCycling Campaign
Plug-In To eCycling
The Plug-In To eCycling Campaign is one of many efforts under EPA's Resource Conservation Challenge (RCC) which seeks to increase the national recycling rate to 35 percent, among other goals. The campaign aims to get the word out about opportunities to reuse and recycle your old computers, TVs, and cell phones, and to build momentum for even more reuse and recycling programs. Under the RCC, EPA is working with electronics manufacturers, retailers, and government agencies to reduce the environmental impacts of electronic products during their production, use, and disposal.
The RoHS, a challenge for the manufacturers
The change from Non-RoHS to RoHS manufacturing was and still is in some cases a great challenge for the companies. Bellow I will note the biggest problems identified so far.
Higher melting temperature: traditional tin/lead solder melts at 180° C (356° F) while lead-free solder melts at 227°C (441°F). This means that the electronic components must be able to support this new soldering temperature in order to allow lead-free solder to be used. The higher melting point of lead free solders increase peak reflow solder temperature from 220°C to 250°C for many applications and as much as 260°C peak for some large boards or sub assemblies.
New alloys under development: tin/lead solder is used for many many years and the soldering process using this alloy is very well known to everybody. The adoption of lead-free solder has made electronics manufacturers aware of a metallurgical phenomenon referred to as ?tin whiskers,? that can seriously affect circuit assembly reliability. Tin whiskers are microscopic single-crystal filaments of the metal that ?grow? from tin-based solders and surface finishes on printed-circuit boards, components, and connectors. Since ?whiskers? are conductive, they can grow long enough to create electrical connections between metals that shouldn?t exist, causing devices and entire systems to short out. In the past lead in solder halted this phenomenon, removing the lead dramatically increases the problem.
Most manufacturers have already adopted Sn-Ag-Cu (SAC) type solder as a lead-free solder for consumer appliance production. The mechanical properties of SAC solder differ greatly from those of conventional Sn-Pb solder. At the beginning of lead-free substitution, SAC displayed high strength but it is now known that cracks in SAC joints progress quickly. In the market today there are many lead-free solders but it is still a new technology and development is still going on with several different solders found and patented every year.
Repair: when repairing electronic equipment, the solder used should also be lead-free. The repair technician should know exactly what kind of solder was used when the equipment was manufactured. Although it is safe to use 99C alloy (99.7% tin, 0.3% copper) when repairing lead-free equipments.
Quality control: the finished appearance of a quality RoHS solder joint has a texture that resembles a leaded cold solder joint.Quality inspectors need to be trained to recognize the appearance of good and bad quality RoHS solder joints.
And add that all other pieces of the electronic equipment ? like components and the printed circuit board (PCB) ? should have almost none of the six banned materials to be considered RoHS-compliant and allowed to be sold in Europe Union. You would probably think ?it is impossible to be done?! No it is not today all electronic and electrical appliances sold or manufactured in the European Union are RoHS conform. The manufacturing companies made it happen because they wanted to (or forced to if you like...).
What is the situation now?
The best thing done until now is by far the RoHS directive although it is implemented mainly by the European Union other countries are benefited also since it is not easy for a company to maintain many production lines. But that is not enough according to greenpeace "the amount of electronic products discarded globally has skyrocketed recently, with 20-50 million tonnes generated every year. If such a huge figure is hard to imagine, think of it like this - if the estimated amount of e-waste generated every year would be put into containers on a train it would go once around the world!"
My personal opinion is that the recycling of e-waste should be at least free of charge for the consumer, also the companies who have benefited from sales of their product have a great responsibility and should design as ?clean? electronics as possible and not only look for the maximum profit.
We cannot punish the companies (or governments...) that don't care about the environment (and that actually means they don't care about us) but we definitely must support the companies that are trying to make green products. Bellow you can find links that can help on your decision and remember to support the companies that go green.
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