It
is estimated that 75% of electronic items are stored due to uncertainty of how
to manage it. These electronic junks lie unattended in houses, offices,
warehouses etc. and normally mixed with household wastes, which are finally
disposed off at landfills. This necessitates implementable management measures.
In
industries management of e-waste should begin at the point of generation. This
can be done by waste minimization techniques and by sustainable product design.
Waste minimization in industries involves adopting:
• Inventory management,
• Production-process
modification,
• Volume reduction,
• Recovery and reuse.
Inventory
management:
Proper
control over the materials used in the manufacturing process is an important
way to reduce waste generation. By reducing both the quantity of hazardous
materials used in the process and the amount of excess raw materials in stock,
the quantity of waste generated can be reduced. This can be done in two ways
i.e. establishing material-purchase review and control procedures and inventory
tracking system.
Developing
review procedures for all material purchased is the first step in establishing
an inventory management program. Procedures should require that all materials
be approved prior to purchase. In the approval process all production materials
are evaluated to examine if they contain hazardous constituents and whether alternative
non-hazardous materials are available.
Another
inventory management procedure for waste reduction is to ensure that only the
needed quantity of a material is ordered. This will require the establishment
of a strict inventory tracking system. Purchase procedures must be implemented
which ensure that materials are ordered only on an as-needed basis and that
only the amount needed for a specific period of time is ordered.
Production-process
modification:
Changes
can be made in the production process, which will reduce waste generation. This
reduction can be accomplished by changing the materials used to make the
product or by the more efficient use of input materials in the production
process or both. Potential waste minimization techniques can be broken down
into three categories:
i)
Improved operating and maintenance procedures,
ii)
Material change and
iii)
Process-equipment modification
Volume
reduction:
Volume
reduction includes those techniques that remove the hazardous portion of a
waste from a non-hazardous portion These techniques are usually to reduce the
volume, and thus the cost of disposing of a waste material. The techniques that
can be used to reduce waste-stream volume can be divided into 2 general
categories:
source
segregation and waste concentration. Segregation of wastes is in many cases a
simple and economical technique for waste reduction. Wastes containing
different types of metals can be treated separately so that the metal value in
the sludge can be recovered. Concentration of a waste stream may increase the
likelihood that the material can be recycled or reused. Methods include gravity
and vacuum filtration, ultra filtration, reverse osmosis, freeze vaporization
etc.
Recovery
and reuse:
This
technique could eliminate waste disposal costs, reduce raw material costs and
provide income from a salable waste. Waste can be recovered on-site, or at an
off-site recovery facility, or through inter industry exchange.
A
number of physical and chemical techniques are available to reclaim a waste
material such as reverse osmosis, electrolysis, condensation, electrolytic
recovery, filtration, centrifugation etc. However recycling of hazardous
products has little environmental benefit if it simply moves the hazards into
secondary products that eventually have to be disposed of. Unless the goal is
to redesign the product to use non-hazardous materials, such recycling is a
false solution.
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