Solid Waste | Dry Refuse |
Solid Waste also known as Dry Refuse includes house refuse, trade refuse, street refuse. This is practically in a dry state. Removal and disposal of dry refuse or solid waste is a very important aspect of environmental sanitation.
- House Refuse – This consists of vegetable and animal waste matters, ashes, cinders, rubbish, debris. All these thus obtained from cleaning and demolition of structures.
- Street Refuse – This consists empty packets, bottles, matches, cigarette boxes, fruit peels, tree leaves, street sweepings etc.
- Trade Refuse – This consists of solid wastes from factories, commercial and business centres, slaughter houses etc.
Solid waste or Dry Refuse consists of garbage, ashes, rubbish, dust etc.
- Garbage – This consists of waste from kitchens, hotels, restaurants in the form of waste food, vegetables, fruits and peels. It is organic in nature and decomposes quickly. Its density is 450 to 900 kg per cubic meter. It should be handled carefully because flies, insects, rats etc. breed in it.
- Ashes – Ashes are incombustible waste products from houses, industries, hearths, furnaces etc. With the introduction of kerosene oil and cooking gas, this waste is gradually decreasing. Its density is 700 to 850 kg per cubic meter.
- Rubbish – It consists of all non-putrescible waste excluding ashes. Common items that falls under this category are – rags, paper, paper packets, broken glass, plastic bottles, broken crockery, broken furniture, card boards, stationery items etc. It thus includes wide variety of combustible and non combustible wastes. Its density is 50 to 400 kg per cubic meter.
Solid waste or Dry Refuse is broadly classified into two heads –
- Organic or Combustible matter – It includes dry animal and vegetable refuse and also cow dung, excreta of birds, tree leaves, sticks, plastic bottles, paper waste, rags. This waste is subject to decay with time and evolve highly offensive odour and gases which are therefore highly detrimental to health.
- Inorganic or Mineral or Non-Combustible matter – This consists of non combustible materials such as grit, dust, mud, metal pieces, metal containers, broken glass and crockery, tiles, waste building material. It is not subject to decay and is therefore not harmful to public health.
Quantity and Composition of Refuse –
The quantity and composition of refuse varies from place to place and also varies from season to season. Ashes increase in winter and in northern latitudes while these are less in summer. The quantity of garbage depends upon the food available and also food habits and standard of living. It also depends whether the town is residential, commercial or industrial. For an average of refuse varies from 0.4 to 0.5 kg / capita / day.
The average composition of refuse by weight is nearly about –
- 25% cinder
- 27% fine dust
- 15% ashes
- 4% empty tins and cans
- 14% putrescible matter
- 2% glass and crockery
- 2% rags
- 1% bone
- 8% miscellaneous matter
Organic waste is 55% while inorganic waste is 45%.