CAMEROON ELECTRONIC WASTE MANAGEMENT STRATEGY
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| E-Waste recycling in Mokolo, Yaounde - Cameroon |
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 by HYSACAM as the case in Cameroon. 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 (Freeman, 1989). 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.
Improvements
in the operation and maintenance of process equipment can result in significant
waste reduction. This can be accomplished by reviewing current operational
procedures or lack of procedures and examination of the production process for
ways to improve its efficiency. Instituting standard operation procedures can
optimise the use of raw materials in the production process and reduce the
potential for materials to be lost through leaks and spills. A strict
maintenance program, which stresses corrective maintenance, can reduce waste
generation caused by equipment failure. An employee-training program is a key
element of any waste reduction program. Training should include correct
operating and handling procedures, proper equipment use, recommended maintenance
and inspection schedules, correct process control specifications and proper
management of waste materials.
Hazardous
materials used in either a product formulation or a production process may be
replaced with a less hazardous or non-hazardous material. This is a very widely
used technique and is applicable to most manufacturing processes.
Implementation of this waste reduction technique may require only some minor
process adjustments or it may require extensive new process equipment. For
example, a circuit board manufacturer can replace solvent-based product with
water-based flux and simultaneously replace solvent vapour degreaser with
detergent parts washer.
Installing
more efficient process equipment or modifying existing equipment to take advantage
of better production techniques can significantly reduce waste generation. New
or updated equipment can use process materials more efficiently producing less
waste. Additionally such efficiency reduces the number of rejected or
off-specification products, thereby reducing the amount of material which has
to be reworked or disposed of. Modifying existing process equipment can be a
very cost-effective method of reducing waste generation. In many cases the
modification can just be relatively simple changes in the way the materials are
handled within the process to ensure that they are not wasted. For example, in
many electronic manufacturing operations, which involve coating a product, such
as electroplating or painting, chemicals are used to strip off coating from
rejected products so that they can be recoated. These chemicals, which can
include acids, caustics, cyanides etc. are often a hazardous waste and must be
properly managed. By reducing the number of parts that have to be reworked, the
quantity of waste can be significantly reduced.
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.
For example,
an electronic component manufacturer can use compaction equipment to reduce
volume of waste cathode ray-tube.
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. For example, a printed-circuit board
manufacturer can use electrolytic recovery to reclaim metals from copper and
tin-lead plating bath.
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.
Sustainable product design
Minimization
of hazardous wastes should be at product design stage itself keeping in mind
the following factors*
- Rethink the product design: Efforts should be made to design a product with fewer amounts of hazardous materials. For example, the efforts to reduce material use are reflected in some new computer designs that are flatter, lighter and more integrated. Other companies propose centralized networks similar to the telephone system.
- Use of renewable materials and energy: Bio-based plastics are plastics made with plant-based chemicals or plant-produced polymers rather than from petrochemicals. Bio-based toners, glues and inks are used more frequently. Solar computers also exist but they are currently very expensive.
- Use of non-renewable materials that are safer: Because many of the materials used are non-renewable, designers could ensure the product is built for re-use, repair and/or upgradeability. Some computer manufacturers such as Dell and Gateway lease out their products thereby ensuring they get them back to further upgrade and lease out again.
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