An integrated waste management system puts to practice the principles of industrial ecology, its objective is the optimisation of the recovery of the materials and energy stored into wastes, contextually guaranteeing health protection and environmental safeguard.
The objectives that the european legislations assignes to the integrated waste cycle, downstream of the activities necessary to prevent waste generation, can be summarised as:
- an effectively organised segregated collection of the recoverable fractions, so as to guarantee the recovery of a high percentage of materials; these materials are thus made available “at cascade” for several industrial sectors;
- an efficient energy recovery, including thermal treatment, from residual wastes and also from rejects of the operations of intermediate treatment of wastes, such as mechanical biological treatment and the cleaning of waste as a preparation for recycling;
- elimination or drastic reduction of the landfilling of biodegradable wastes: this objective can also be reached by the recovery of matter and energy from organic refuses, either from food or green areas management.
The description we propose of a specific integrated management system – summarised by means of the wastes and materials flows and by the network of actors – requires to select at least the knowledge of:
- the actors involved in the network
- the number, type and dimension of the all equipment and all the plants that serve the integrated system
- the quantification of the flows of wastes that move along with the different phase of management
- the ensemble of the organisational and administrative solutions which are adopted in each phase of the waste hierarchy
- the constraints and opportunities created by taxes / incentives applied to the different phases
- the markets of materials and energy.
This type of representation of an integrated waste management system, and its subdivision in three main flows – residual wastes sent to energy recovery; waste collected by segregated collection to be sent to material recovery, and organic wastes which can be treated to recover both matter and energy – is appropriate to the description of a wicked problem because:
- it highlights complexity, showing t the same time all the flows that are formed as a consequence of the organisation of waste collection and of the types of wastes collected;
- by separating the flows of different wastes – residual form separately collected – it allows to compose and evaluate alternative management solutions, for instance by changing type and number of plants used in a each hierarchical phase;
- it evaluates every alternative by observing the system as a whole and it does not externalise the impacts like it is done when the analysis of is performed on a partial system.