Quantities of Solid Waste
The information regarding waste quantity and density coupled with waste generation rate (by weight), is important while assessing the payload capacity of the collection equipment. It is possible to estimate the number of vehicles required for the collection and transportation of waste each day.
While per capita waste generation is a statistic, which is necessary for indicating trends in consumption and production, the total we ight and volume of wastes generated by the community served by the management system are of greater importance in planning and design. As in all other aspects of data collection for the planning and design phases, data on waste generation, weight and volume should be collected by each authority for application in its own area of operation.
3.3.6.1 Per Capita Quantity of Municipal Solid Waste in Indian Urban Centres
The quantity of waste from various cities was accurately measured by NEERI. On the basis of quantity transported per trip and the number of trips made per day the daily quantity was determined. The quantity of waste produced is lesser than that in developed countries and is normally observed to vary between 0.2-0.6 kg/capita/day. Value upto 0.6 kg/capita/day are observed in metropolitan cities (Table 3.6). The total waste generation in urban areas in the country is estimated to be around 38 million tonnes per annum.
Forecasting waste quantities in the future is as difficult as it is in predicting changes of waste composition. The factors promoting change in waste composition are equally relevant to changes in waste generation. An additional point, worthy of note, is the change of density of the waste as the waste moves through the management system, from the source of generation to the point of ultimate disposal. Storage methods, salvaging activities, exposure to the weather, handling methods and decomposition, all have their effects on changes in waste density. As a general rule, the lower the level of economic development, the greater the change between generation and disposal. Increases in density of 100% are common in developing countries, which mean that the volume of wastes decreases by half.
3.3.6.2 Estimation of Future Per Capita Waste Quantity
For purposes of project identification, where an indication of service level must be estimated and data from the project preparation stage have not yet been developed, the following municipal refuse generation rates are suggested:
Residential refuse : 0.3 to 0.6 kg/cap/day
Commercial refuse : 0.1 to 0.2 kg/cap/day
Street sweepings : 0.05 to 0.2 kg/cap/day
Institutional refuse : 0.05 to 0.2 kg/cap/day
If industrial solid waste is included in municipal refuse for collection and/or disposal purposes, from 0.1 to 1.0 kg/cap/day may be added at the appropriate step where the municipality must estimate service delivery requirements. These generation rates are subject to considerable site-specific factors and are required to be supported by field data.
