Waste Management | Concepts, Categories | Jamii-Health
Waste management is the administration of all activities involved in collection, source separation, storage, transport, processing, recycling, disposal and monitoring of waste materials.
However, I personally think that defining what it is, is the first thing we need to focus on.
In addition, all items that we no longer use for or intend to get rid of or have discarded then is a waste.
Well, what does it consist of?
Actually, it involves the management of solids, liquids, hazardous and nuclear wastes. Countries all over the world have different waste management practices.
Further, the practices also not the same in regions, residential urban, rural, commercial and industrial areas.
Traditionally, waste management involves collection, processing and disposal of waste materials.
Now, why do we manage waste?
We do this to reduce negative effects on our health, environment, aesthetics (beauty of the scenery/area) and amenity.
More so, we manage waste to recover resources like nutrients, raw materials.
Early waste management strategies.
Industrial revolution in the 18th century created way to overpopulation, mostly in urban areas. People disposed wastes anyhow.
Nevertheless, there were no waste management policies put in place.
- Dilute and disperse which involves disposal of industrial wastes directly into rivers.
- Concentrate and contain that consists of moving waste to relatively few sites that could be controlled such as burrow pits, disused mines quarries.
- Ancient world e.g. Greece, wastes were disposed in pits and covered.
Characteristics of sewage.
- pH: the pH of sewage is neutral.
- BOD (biochemical oxygen demand) which is the measure of the amount of oxygen required by microbes in decomposition which is about 0.4 mg/l.
- COD (chemical oxygen demand) includes oxygen consuming capacity of organic matter, amount of oxygen consumed by chemical oxidant K2CR2O7 which is about 0.4 mg/l (according to waste management study).
- Nutrients: Phosphorus and nitrogen; together they cause algae bloom.
- DO (dissolved oxygen): This is the amount of oxygen available in waste water important in the decomposition of organic matter.
- To gain maximum practical benefit and minimize waste.
- Source reduction- Simply, to minimize waste from the source.
Classification of Waste Management.
Strategies Relative to Their Desirability/Preference
To extract maximum practical benefit from products and minimize waste.
More so, there is a 4th R!
4th R- Re-think
Extended Producer Responsibility
Polluter Pays Principle
Categories of Waste Materials
Normally, they vary with countries. Therefore, classification of waste is based on:-
- Source (origin)
- Physical/chemical/biochemical properties
- Potentially hazardous components
- Volume generating.
Naturally, wastes are in the form of solid, liquid and gas and occur as solid wastes, sewage, industrial effluent.
Solid wastes contain less than 70% water.
Meanwhile, liquid wastes contain less than 1% solid and have higher concentration of dissolved salts and metals.
However, there is what we call sludge (semi-solid) which contains 3-25% solid.
The broad classes of wastes include:
U.S Federal Regulations on Waste Management
It classifies wastes into 3 classes :-
i.) Non-hazardous wastes– These due to their nature, pose no immediate threat to human health and environment.
ii.) Hazardous wastes- They are grouped into two:
- Those with common hazard: Ignitability and reactivity properties.
- Leachable toxic components.
iii.) The special wastes– They have specific characteristics and are regulated with specific guidelines e.g. radioactive wastes and medical wastes.