Showing posts with label metric. Show all posts
Showing posts with label metric. Show all posts

Introduction of computer recycling for Gold


Obsolete computers contain significant amounts of recoverable materials including metals from wires and circuit boards, glass from monitors, and plastics from casings (fig. 1). For example, 1 metric ton (t) of electronic scrap from personal computers (PC’s) contains more gold than that recovered from 17 t of gold ore. In 1998, the amount of gold recovered from electronic scrap in the United States was equivalent to that recovered from more than 2 million metric tons (Mt) of gold ore and waste.

The amount of computer waste increases annually as electronic systems play an increasingly important role in all aspects of technology, but significant amounts of material used in the devices are not recovered. Because microchip development is so rapid (Hamilton and Takahashi, 1996), users are able, every 18 months, to purchase computers that are twice as powerful at the same price as those currently available (Jung, 1999). This cyclic trend (with its inherent surplus of old computer components) has been sustained for nearly 20 years of recent computer history. To meet consumer demand, the computer and electronics industry has become the largest manufacturing employer in the United States, representing 11 percent of the gross domestic product and growing at an annual rate of 4 percent (Porter, 1998).

The quantities and types of materials used in computer products to meet this demand are great and varied, as is the potential to recover these computers and their materials for reuse, remanufacturing, and recycling. In 1998, nearly 43 million new PC’s and notebook computers were purchased by consumers in the United States; and it is estimated that in the year 2003, nearly 70 million computers will be purchased by consumers in the United States (National Safety Council, 1999).

In 1997, it was estimated that between 1985 and 2005, approximately 325 million PC’s would become obsolete in the United States (Jung, 1999). In a business environment, the useful life of a PC is about 2 years, while in homes PC’s are used from 3 to 5 years (Jung, 1999). Between 14 and 20 million PC’s become obsolete every year in the United States. About 75 percent of these obsolete computers are not discarded because their owners perceive them to be valuable (Goodrich, 1999); a portion of these will not be recycled. For every three computers purchased in the United States, two will be taken out of service, and this ratio is expected to increase to 1:1 by 2005. It is projected that by 2005, a total of 680 million PC’s will have been sold worldwide. Of that total, it is estimated that 150 million computers will be recycled that year and 55 million computers will end up in landfills along with unreclaimed portions of the 150 million recycled computers (Hamilton and Takahashi, 1996).

Recycling Flow




Figure 2 is a generalized materials flow diagram that shows what happens to obsolete PC’s and their components.

This figure includes

• computers that owners retain (but do not use) or donate or dispose of directly or indirectly to municipal waste and hazardous waste landfills (The U.S. Environmental Protection Agency (EPA) categorizes cathode ray tubes (CRT’s) as hazardous waste, although exemptions exist for disposal of equipment generated by households and small business.)

• computers that can be refurbished and sold or donated by companies or organizations

• what happens to computers that can be dismantled and sold for reuse, melted and recycled, incinerated as a fuel for producing energy, and disposed of in landfills.

Computers and otherelectronic devices represent a large resource of potentially recoverablematerial. Table 1 lists selected types and amounts of material reportedly recovered in 1997 and 1998 from computer and other electronic scrap. In 1998, about 2.6 million PC’s and notebook computers were recycled in the United States, and this number is expected to quadruple by 2003 (National Safety Council, 1999). Recyclers received nearly 50 percent of electronic products directly from manufacturers; about 30 percent from large companies that utilize electronics in their business; and the rest from small companies, government offices, and individuals (National Safety Council, 1999).

Some scrap is unwanted because of low precious metal content and the potentially hazardous nature of some of its materials. For example, the presence of lead in some electronic scrap prevents it from being placed in a municipal landfill. Some refiners actually have to charge as much as $1 per pound to process the scrap because of these deleterious materials (Broughton, 1996).

Some scrap was exported to Taiwan for open burning and chemical processing; however, the Taiwanese government had reportedly become increasingly concerned about the environmental damage caused by this practice (Broughton, 1996). Chinese and other Asian consumers pay 15 to 20 cents per pound for electronic scrap on the U.S. West Coast (Goodrich, 1999). Environmental regulations are less strict (or not enforced), and labor costs are much lower in some of these countries.
Gold recycling

How to Recycle Gold From a Computer?


Most older CPUs have gold components on the circuit boards. Taking the whole board out is the first step. Open up the case for your computer to access the electronics inside. You'll need a small screwdriver for this step.


Take out the electronic components. Once inside, you'll see the mother boards and memory chips. Pull out all the tasty bits and lay in a bin. The case and other parts are also recyclable. Pack them up separately for an environmentally responsible disposal.

Stock pile it. A study done by EOEarth states: "1 metric ton (t) of electronic scrap from personal computers (PC's) contains more gold than that recovered from 17 t of gold ore". One computer won't have enough gold to make you rich. Yet, if you begin to collect abandoned computers, you can save all your gold parts. This will make going through the process of reverse electro plating it by the recycling center worth the time and effort.

Separate your pieces. Most computer recycling centers ask that you separate metals and plastics. Don't just focus on the gold in your computer. Be sure to recycle the rest of the plastics and electronics. To keep down clutter, immediately disassemble your old computers and take all the plastics in for recycling immediately.

Take it in for recycling. You'll see that your computer has all kinds of shiny metallics in it. Many of these metals are also recyclable. Taking your PC to a computer recycle center is the easiest way to retrieve your precious metals. You'll want to find a precious metals refinery to send your circuit boards and chips to. They will do all the work, and they'll give you a fair price for the efforts. See our website for more tips of how to recycle gold from electronic waste.
Gold recycling