Unas tarjetas/placas electrónicas con componentes que tienen alto valor no pueden ser trituradas debido a precisamente que son útiles de una forma u otra. Es por eso que existen varias formas para su desmantelamiento. La palabra "shredded " para las PCB de alto valor no significa que son trituradas sino más bien desincorporadas o los componentes de valor son desmontados por otros medios. El valor estaría en la cantidad de metales preciosos que fue usado en su construcción. Las que son mecánicamente trituradas sus componentes son desmontados y la tarjeta no tiene valor recuperable suficiente en lo que se refiere a metales.
Las tarjetas/placas son clasificadas según el uso, por ejemplo:

Bajo valor: tarjetas de televisores, impresoras, telefonos in-halámbricos. Triturados después de separar Aluminio e hierro

Medio valor: tarjetas de computadores personales y laptop.

Alto valor:tarjetas de circuitos de computadores Maiframe, telefonos celulares/portátiles.

De todas maneras, seguidamente hay una información sobre el tema de lo que hacen el la UK y otro articulo de interés.

Executive Summary
Within the waste electrical and electronic equipment (WEEE) recycling industry, recyclers use a variety of methods for extracting printed circuit boards (PCBs) from WEEE. This report provides an overview of the principal recovery techniques used in the UK, including a description of each and the rationale behind why a company decides to use one technique over another.

The research found that there are four key techniques used in the UK for the recovery of PCBs:

 Fully manual segregation – segregation of target items from other WEEE streams, followed by manual dismantling of equipment;

 Fully manual segregation, including re-use -– as above but incorporates the recovery of specific PCBs/processor chips for re-use;

 Semi-automated with commercial shredding – Mechanical shredding of WEEE for size reduction and separation of saleable ferrous and non-ferrous metals, with manual downstream picking operations to recover PCBs and other components. This process is best suited for recovering PCBs from items which are not cost effective to manually sort or items where the PCBs are physically attached, e.g. welded, and cannot be manually removed; and

 Semi-automated with commercial smashing – manual removal of streams requiring manual recovery. Spinning and smashing of the remaining WEEE into smaller components followed by magnetic separation; and finally manual picking lines.
The project identified that the technique used is dependent on the type of WEEE being processed and the value of the PCBs. Manual recovery techniques are typically used for extracting high grade PCBs, mainly from IT and communications equipment as well as flat panel displays (FPDs), whereas automated recovery techniques are typically used for large domestic appliances (LDAs) and small mixed WEEE, where it is not cost effective to use manual techniques.
The grade of PCB is dependent on the quantity of precious metals it contains such as gold and silver, which can vary between the category of WEEE and its age. Sophisticated IT equipment such as computers, telecommunications equipment, and flat panel displays will often contain high grade PCBs with good quantities of precious metals, however PCBs from cathode ray tubes (CRTs), other small mixed WEEE and white goods will typically be low grade (or not cost effective to recover manually).

As PCBs are recovered for their precious metal content, their value is influenced by global prices. PCBs are considered a commodity and the value that UK operators receive is dependent on the prevailing market price of gold and other precious metals. In order to identify the value of recovering PCBs to a UK WEEE recycler a financial assessment was conducted which took into account treatment costs, technique recovery
Techniques for Recovering Printed Circuit Boards (PCBs) 1

Materials we treat



Umicore is a world leader in the eco-efficient recycling of a wide range of electronic materials. This means achieving the environmental and economic balance in recycling. It entails maximizing both the physical recycling of metals (or other materials) and the revenue obtained, while minimizing the associated environmental burden and total cost. An eco-efficient process also considers the "environmental fingerprint" of materials, i.e. how much negative environmental impact can be saved by recycling, for example, a metal instead of producing it "new" by mining. Due to the considerable (environmental) impact of turning precious metals from low grade ores into pure metals, a high overall recycling yield of them has not merely economic benefits, but also substantial ecological advantages (recycling 1 kg of gold is much more beneficial, both financially and ecologically, than recycling 1 kg of iron). In a purely weight-based calculation of recycling-rates, this effect is not considered properly.

High value to low value material

Please be aware that "low" and "high" value are relative terms only, and even a "high value" electronic scrap is low value compared with e.g. a precious metal catalyst. The following examples give some general indications for typical material categories:

low value: TV-boards, monitor boards, printer boards, cordless phones, calculators, shredded bulk material after Al-/Fe-separation, etc.
medium value: PC-boards, laptop-and handheld-computer circuit boards, etc.
high value: Circuit boards from mainframes, mobile phones, ICs, MLCCs

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Note added at 8 hrs (2014-12-31 02:32:46 GMT)
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Corrección
tarjetas/placas de computadores Maiframe, telefonos portátiles trituradas