Wednesday, July 04, 2007

Hierarchy of Solid Waste Management

Used to rank actions to implement programs within the community.

A. Source reduction
B. Recycling/reuse
C. Waste transfor.
D. landfilling

E.g. ISWM hierarchy adopted by the US EPA...

A. Source reduction can be achieved by design, manufacture and packaging of products also selective buying and reuse.

B. Recycling helps to reduce the demand on resources and decreases the amount to be landfilled. It involves

* Separation and collection of waste materials
* Preparation of these materials for reuse,reprocessing and remanufacture.

C. Waste transformation is supplied by altering the waste physically, chemically, and biologically (decreases the amount to be landfilled)

D. Landfilling is ultimately used for, SW that cannot be recycled and of no further
use,residual matter after SW separated in materials recovery facility (MRF), Residual matter after recovery of conversion products or energy.

Planning an integrated waste system for a given region should involve comparison of the environmental impacts and economic costs of different schemes to determine which are environmentally and economically sustainable in that region

INTEGRATED SOLID WASTE MANAGEMENT

When all of the functional elements have been evaluated for use and all interfaces and connections between elements matched for effectiveness and economy - community developed an ISWM system.

In dealing waste there are two fundamental requirements;
- Less waste
- Effective system for managing waste still produced

The costs of raw materials and energy, and rising disposal costs for commercial and industrial waste will ensure that waste reduction continues to be pursued by industry for
- Economic
- Environmental reasons

Designing an effective solid waste management system

Strive for both of the following;
- Environmental sustainability
- Economic sustainability

To achieve these, the system should be integrated; a system that deals with
- All types of solid waste materials
- All sources of solid waste (domestic, industrial,...)
- After waste collection and sorting


Note that to handling all waste in an environmentally sustainable way requires a range of the treatment options.

Landfill is the only method that can handle all wastes alone but may posses environmental problems.

Using other options before landfilling can reduce or eliminate some waste streams, reduce volume, improve physical and chemical stability of the residue space requirements decreases and also environmental impacts decreases.