Application of physical system theory and goal programming to modelling and analysis of waste management in national planning

Conventionally, national planning models have emphasized two major interfaces of the economic system, i.e. the input, and the output. The third important interface, i.e. waste, has not received the attention it deserves in the economic planning process. Attempts to include waste parameters in economic environmental modelling has been limited to tackling certain environmental considerations in national planning. The broader perspective of waste management (WM) has, by and large, been ignored in most of the literature in this context. This paper presents a graph theoretical system model of a multi-sectoral national economy including WM sectors. The system model of the economy has been integrated to a multi-objective goal programming model to fulfil the WM goals in a particular planning period. The model takes care of a variety of factors like resource structure, standard of living, sustained economic growth, waste recycling, environmental quality, etc. The model may be applied to determine the optimal quantity of waste to be generated in various sectors, and to assess optimal waste recycling efforts, along with the type of technology to be employed in various sectors. The application of the model has been illustrated by the example of a two sector economy having one production sector and one WM sector, and the sensitivity analysis has been carried out for alternate objective functions. Statistical analysis and the interpretation of the results are presented. The different variables and goals have been categorized as highly sensitive, moderately sensitive and less sensitive. The discussion of the results has been extended to show how the proposed model can be applied to real life national planning from a WM viewpoint.