WASTE & WASTE MANAGEMENT
Subject: Community Health Nursing
Definition of waste
“‘Wastes’ are substances or objects, which are disposed of or are intended to be disposed of or are required to be disposed of by the provisions of national law”.
Refuse or solid waste
It may be defined as being the waste materials from homes, restaurants and other establishment of the community (market, street etc). It includes mainly garbage, rubbish and ashes.
Sewage (Excreta or night soil): It is the waste liquid from residence, buildings and industries containing solid and liquid excreta.
Sullage: It is applied to the waste water from houses, streets, trades, industries and factories unmixed with fecal matter.
Types of waste:There are many waste types defined by modern systems of waste management, notably including-
- Municipal Waste: includes Household waste (garbage- waste from food; rubbish-paper, polythen bag, empty can, broken piece etc; ash-burning coal, wood and other fuel), Commercial waste, and Demolition waste.
- Hazardous Waste: includes Industrial waste.
- Bio-medical Waste: includes Clinical waste.
- Special Hazardous waste: includes radioactive waste, explosives waste, and Electronic waste (e-waste).
Health hazards due to waste
- Nuisance- waste itself is a nuisance and again it undergoes putrefaction and produces foul smell and looking dirty.
- The organic portion of the waste ferments and favors fly breeding.
- The garbage in the refuse attracts rats and vermin’s.
- Pollution of water due to washing of deposits of fermenting refuses by rain water.
- Pollution of air, soil.
- Contamination of food and water.
- Propagation of flies and cause fly borne diseases.
Health hazards of improper excreta( night soil) disposal
- Nuisance- Produces foul smell and ugly scene.
- Pollution of air spread of air borne diseases.
- Pollution of soil spread of soil borne diseases.
- Pollution of water spread of water borne diseases.
- Contamination of foods.
- Propagation of flies and cause fly borne diseases.
Faecal/ Excreta borne disease
- Bacterial diseases
- Cholera and diarrhoeal diseases
- Bacillary desentry
- Enteric fever
- Viral diseases
- Infective hepatitis
- Rota viral diarrhoea
- Parasitic diseases
- Helminthic infestation
- Round worm
- Hook worm
- Thread worm
- Tape worm
- Pin worm
Methods of excreta disposal
- Un-sewered areas ( no underground drain)
- Service type
- Non service type
- Bore hole latrine
- Pit latrine
- Water seal latrine
- Septic tank
- Chemical closet.
- Latrine suitable for temporary use
- Shallow trench latrine
- Deep trench latrine ( pit latrine, borehole latrine)
- Sewered areas ( underground drain)
- Primary treatment
- Remove of grit
- Plain sedimentation
- Secondary treatment
- Trickling filters
- Digestion of slug
- Activated of slug
- Other methods
- Sea out full
- River out full
- Sewage farming
- Oxidation pond
Waste management is the collection, transport, processing or disposal, managing and monitoring of waste materials. The term usually relates to materials produced by human activity, and the process is generally undertaken to reduce their effect on health, the environment or aesthetics. All waste materials, whether they are solid, liquid, gaseous or radioactive fall within the remit of waste management.
- Storage of refuse: Provision of sufficient number of container’s to hold the volume of waste produced between collections. It’s surrounding should be maintained in a hygienic way.
- Collection of waste: It means collection of waste from domestic containers to public dustbin. It should be frequent and systemic.
- Removal of waste: From public dustbin by especially constructed vehicles. Night or early morning collection is preferable.
- Final disposal of waste: The methods commonly employed are dumping, sanitary land fill, composting and incineration.
Methods/techniques of waste disposal
- Sanitary Landfill
- Manure pit
- Windrow composting
- Damping: Refuse is dumped in low lying areas partly as a method of reclamation of land but mainly as an easy method of disposal of dry refuse. As a result of bacterial action, refuse decreases in volume and is converted into humus.
- Sanitary Landfill: It is the most satisfactory method of refuse disposal where suitable land is available. It differ from ordinary damping in that the material is placed in a trench or other prepared area, adequately compacted and covered with earth at the end of the working day. The term modified sanitary landfill has been applied to those operations where compaction and covering are accomplished once or twice a week.3 methods needed in this operation-
- The trench methods
- The ramp methods
- The area methods.
- Incineration: Incineration is a waste treatment process that involves the combustion of organic substances contained in waste materials. Incineration and other high-temperature waste treatment systems are described as “thermal treatment”. Incineration of waste materials converts the waste into ash, flue gas, and heat. Hospital refuse that is particularly dangerous is best disposal of by incineration.
- Composting: It is the method of combined disposal of refuse and night soil or sludge. It is a process of nature whereby organic matter (plant material, food scraps, and paper products) breaks down under bacterial actions resulting in the formation of relatively stable humus after a period of weeks or months like material called the compost which has considerable manure value for the soil. It is used in gardens, landscaping, horticulture, and agriculture. The principal by products are carbon-dioxide, water and heat.
- Manure pits: In rural areas, refuse can be disposed by digging manure pits by the individual’s householders. The garbage, cattle dung, straw and leaves should be dumped into the manure pits and covered with earth after each day’s dumping.
- Burial: It is suitable for small camps. A trench 2.5 m wide and 2 m deep is excavated and at the end of each day the refuse is covered with 20-30 cm of earth. When the level in the trench is 40 cm from ground level, the trench is filled with earth and compacted and a new trench is drug out.
- Recycling : Recycling is a process to change materials (waste) into new products to prevent waste of potentially useful materials, reduce the consumption of fresh raw materials, reduce energy usage, reduce air pollution (from incineration) and water pollution (from land filling. Recycling is a key component of modern waste reduction and is the third component of the “Reduce, Reuse, and Recycle” waste hierarchy.Recyclable materials include many kinds of glass, paper, metal, plastic, textiles, and electronics.
- Windrow composting: In agriculture, windrow composting is the production of compost by piling organic matter or biodegradable waste, such as animal manure and crop residues, in long rows (windrows). This method is suited to producing large volumes of compost. Windrow composting is a commonly used farm scale composting method.An important method of waste management is the prevention of waste material being created, also known as waste reduction. Methods of avoidance include reuse of second-hand products, repairing broken items instead of buying new, designing products to be refillable or reusable (such as cotton instead of plastic shopping bags), encouraging consumers to avoid using disposable products (such as disposable cutlery), removing any food/liquid remains from cans, packaging, and designing products that use less material to achieve the same purpose (for example, light weighting of beverage cans).
Alternative waste treatment technologies:In the UK these are sometimes termed advanced waste treatment technologies, even though these technologies are not necessarily more complex than the established technologies.
- Anaerobic digestion.
- Alcohol/ethanol production.
- Gas Plasma: Gasification followed by syngas plasma polishing (commercial test scale).
- Mechanical heat treatment.
- Plasma arc waste disposal (commercial demonstration scale).
- Sewage treatment.
- Tunnel composting.
- Waste autoclave.
- (lecture by baby kirttania)