e-waste management

E-Waste Management in India (E-Parisaara Pvt.

Ltd)

Why worry about E-waste ?? E waste is a rapidly growing problem

Phenomenal growth in field of electronics leading to more e-waste

E-waste do not decompose

Lack of technological advancement

Highly toxic elements are present

Content of WEEE

It contains more than 1000 components

Toxic substances : lead,mercury,arsenic,cadmium,selenium etc.

Precious metals such as gold, silver

Ordinary metal such as copper, zinc, aluminium

Fig: WEEE material composition(ETCRWM)

E-Parisaara First govt. authorized eco-friendly recycling unit

First scientific e-waste recycling technologies used

Aim to reduce pollution, landfills and to recover valuable metals, plastic and glass from E-waste

Simple and low cost machines being used ex: shredder, crusher etc.

Process of converting waste to Raw material

Manual Dismantling

Hands on segregation

Shredding

Density separation

Note: First three are pending for patent so no exact information of process used

Other processes in E-Parisaara

Toner cartridge dismantling

Gold recovery from Printed Circuit board strips and components

Silver recovery from silver coated components

Shredding of printed circuit board

Recycling of E-Waste can be broadly divided into

• Disassembly: selectively disassembly, targeting on singling out hazardous or valuable components for special treatment

• Upgrading: using mechanical processing and/or metallurgical processing to up-grade desirable materials

• Refining: recovered materials are retreated or purified by using chemical (metallurgical) processing so as to be acceptable for their

original using.

Fig: Block diagram for first step disassembly

Chemical processes in EEE recycling

Pyro metallurgical recovery

Hydro metallurgical recovery

Bio metallurgical recovery

Pyro metallurgical recovery

Includes smelting in blast furnace

Drossing

Sintering

Melting

Reaction in gas phase at high temperature

Existing technologies

Norlando process

Boliden Ronnsker smelter

Umicore’s precious metal recovery

Dunn’s patent for Gold refining

Fig: Offgas emission control instalments in smelters

Limitation of Pyro Metallurgical process

Cannot recover aluminium and iron

HFR might lead to dioxins formation

Large amount of ceramic and glass makes PM extraction difficult

Only partial separation possible

Hydrometallurgical process

Consists of series of acid or caustic leaches of solid material

The leached solution is subjected to following methods

1. Precipitation of impurities

2. Solvent extraction

3. Adsorption

4. Ion exchange

Gold Adsorption on Activated carbon

Ag complexes adsorption also done

Leached Ag/Au gets adsorbed on activated carbon surface

Mechanism and kinetics of adsorption

La Brooy Model

Advantages of Hydro Metallurgical process

More exact More predictable Easily controllable PM recovery efficiency is higher

Disadvantages of Hydro Metallurgical process

Choice of solution is difficult Solution required in large amount leading to extra expense

Future scopes

Lack of technologies available in India for E-waste management

Very promising field for innovations

Lack of efficiency of formal sector role gives way to new start up's

PM recovery is a open field for exploration in India as of now

Thank You !!!

References

• www.ewasteindia.com• Metallurgical recovery of metals from e-waste : Journal of

hazardous material 158(2008)228-256• E-waste management: A case study of Bangalore(Research

journal of environmental and earth science)• Global perspective on e-waste( EIA review 25(2005)436-458)• E-waste management: An emerging environmental and health

issue in India• Development of an integrated model to recover precious metal

from electronic scrap(science direct)