What is solid waste?
• Each household generates garbage or waste day in and day out. Items that we no longer need or do not have any further use for fall in the category of waste, and we tend to throw them away. • With the progress of civilization, the waste generated became of a more complex nature. • The increase in population was also largely responsible for the increase in solid waste.
Types of solid waste Solid waste can be classified into different types depending on their source: • municipal waste, • Industrial waste, and • Biomedical waste or hospital waste.
Municipal solid waste • Municipal solid waste consists of household waste, construction and debris, and waste from streets. • This garbage is generated mainly from residential and commercial places. • With the change in lifestyle and food habits, the amount of municipal solid waste has been increasing rapidly and its composition changing.
Garbage: the four broad categories • Organic waste: kitchen waste, vegetables, flowers, leaves, fruits. • Toxic waste: old medicines, paints, chemicals, bulbs, spray cans, fertilizer and pesticide containers, batteries, shoe polish. • Recyclable: paper, glass, metals, plastics. • Soiled: hospital waste such as cloth soiled with blood and other body fluids.
WHAT ARE THE FFECTS OF IMPROPER DISPOSAL OF SOLID WASTE? The type and amount of solid waste with improper disposal methods, increases the risk of health effects in humans, causes damage to ecosystems and accelerates the destruction of the environment. Some of these environmental effects are: • Pollution of surface and ground water • Clogging of drains. • Open decomposition (rotting) that can lead to the development of unpleasant odor. • Breeding of vectors e.g. flies and rats. • Increase risk of diseases such as: Typhoid- Malaria- Yellow fever • Litters the land and makes it look ugly.
Treatment and disposal of municipal waste • Open dumps Open dumps refer to uncovered areas that are used to dump solid waste of all kinds. The waste is untreated, uncovered, and not segregated. It is the breeding ground for flies, rats, and other insects that spread disease. The rainwater run-off from these dumps contaminates nearby land and water thereby spreading disease. In some countries, open dumps are being phased out.
Landfill • Facility in which solid waste from municipal and/or industrial sources is disposed; sanitary landfills are those landfills that are operated in accordance with current environmental protection standards.
• Incineration plants This process of burning waste in large furnaces is known as incineration. Both the fly ash and the ash that is left in the furnace after burning have high concentrations of dangerous toxins such as dioxins and heavy metals. Disposing of this ash is a problem. The ash that is buried at the landfills leaches the area and cause severe contamination. Burning garbage is not a clean process as it produces tones of toxic ash and pollutes the air and water. In fact, at present, incineration is kept as the last resort and is used mainly for treating the infectious waste.
• Composting composting is one of the oldest forms of disposal. It is the natural process of decomposition of organic waste that yields manure or compost, which is very rich in nutrients. Composting is a biological process in which micro-organisms, mainly fungi and bacteria, convert degradable organic waste into humus like substance. This finished product, which looks like soil, is high in carbon and nitrogen and is an excellent medium for growing plants.
• It is allowing trimmings, vegetable/fruit peels and scraps and other organic materials to decompose naturally under controlled conditions, after which the product can be used as garden manure. • Composting also reduces the amount of material reaching landfills, space is saved and landfills can last longer. • Compost your yard trimmings and food scraps.
Design of the Aerated Pile Composting System
WHAT WE CAN DO! • Continue the same old habit of disposal in new places? Certainly Not! • We have to recognize the consequences of improper solid waste disposal on the environment and our health and change our attitudes. • It is time we start disposing our solid waste in the right places, such as: • · landfills • · incinerators • · bins • In addition we can practice The Three R’s!
Understanding the 3R Concept
When we look at the 3R concept within the production cycle, we can see a number of ways in which 'reduce, reuse, recycle' aspects can be incorporated.
(I) REDUCE • The process of decreasing the amount of waste generated at each step of product development or use. • The amount of solid waste produced can be reduced by buying products: • Without extra packaging e.g. plastic and paper wrapping. • That can be used more than once. • That last longer.
• Old newspapers, magazines and bottles can be sold to the man who buys these items from homes. • In your own home you can contribute to waste reduction and the recycling and reuse of certain items.
(II) REUSE We can reuse many things before we throw them away. Therefore we could: • Reuse bags (paper and plastic), containers, paper and other items. • Sell or donate things you no longer use to people who will use them, e.g. clothing and shoes. • Repair shoes, boots, handbags and other items before you consider ‘throwing away’. • Convert cans and plastic containers into plant pots.
(III) RECYCLE • To separate a given waste material from other wastes and to process it so that it can be used again in a form similar to its original use. • Recycling involves the collection of used and discarded materials processing these materials and making them into new products. • It reduces the amount of waste that is thrown into the community dust bins thereby making the environment cleaner and the air more fresh to breathe.
Pollution Prevention Practices can Help • Improve the quality of your products and services. • Reduce inventory costs by using fewer raw materials. • Reduce hazardous and non-hazardous waste disposal and/or treatment costs. • Reduce wastewater disposal and/or treatment costs.
Waste Management
What is the solid waste management hierarchy?
