Concept Integrated Waste Management (IWM)
Integrated Waste Management, or IWM, is a tool to determine the most energy-efficient, least-polluting ways to deal with the various components and items of a community’s solid waste stream.
The IWM hierarchy is based upon the material and energy that is embodied in solid waste and that is associated with its recycling and disposal.
The Goals of Integrated Waste Management
The twin goals of IWM are to:
Retain as much as possible of that energy and those materials in a useful state, and
Avoid releasing that energy or matter into the environment as a pollutant.
Hierarchy of Integrated Waste Management
Integrated waste management sets up a hierarchy of approaches and technologies for managing solid waste in order to meet these goals. Generally, the farther “up” the hierarchy from which the technology is chosen, the more benefits in efficiency and retained economic value.
Read Also : Advantages of Proper Waste Recycling and Waste Reuse
The very highest option in the hierarchy is, don’t create the solid waste in the first place, and is termed “source reduction.” Source reduction can be done in several ways:
Manufacturing processes can be devised which create fewer or less toxic waste by-products
Consumers can choose not to purchase products with excessive packaging or
Consumers can choose not to purchase products which are unnecessary “luxuries,” which require unjustifiably large amounts of energy or natural resources to manufacture, or which cause toxic waste problems in manufacture, use, or disposal.
The other higher level IWM options are (in order):
Reuse – The use of a product more than once in its same form for the same or similar purpose.
Fig:(a): Hierarchy of Integrated Solid Waste Management
Recycling — The process, by which materials otherwise destined for disposal are collected, processed, remanufactured into the same or different product, and purchased as new products.
Composting — The controlled process whereby organic materials are biologically broken down and converted into a stabilized humus material.
Materials retain their value for longer periods of time if they are handled within these “top four” levels of the IWM hierarchy.
If it can’t be recycled for some reason, several options are available which limit the use of the box’s energy to a one-time recapture.
The box might be composted for use as a soil amendment; made into refuse-derived fuel to be burned in a boiler for its energy value; or it might be mass-burned (incineration with energy recovery) together with mixed solid waste to produce steam or electricity.
The next choices are simply to reduce the volume of the waste before disposal. Baling the box is one option, as is burning it without energy recovery, just to reduce the volume to ash
Finally, after all else has been considered or done, land filling (burial) is the last resort. Not only will the box exit the loop of economic usefulness, but it may become part of a pollution problem and, at least, occupy costly landfill space
When we choose a waste management option for the box after it has been used once.
Goal No.1 of IWM is to retain as much of its current usefulness as possible in order to avoid having to use the same amount of wood pulp and energy to make another box to do the same job again.
Read Also : Strategies for Carrying out Waste Recycling
Goal No. 2 is to keep the energy-matter represented by that box tied up in a useful product and not released as a pollutant (which the box might become if it ends up along a roadside as litter, or buried in a landfill where its usefulness will be forgone indefinitely).
Fig.©: Box Potential According to the IWM Hierarchy
