Production of stone aggregates is by far the largest non-energy mining activity; approximately 87% of all aggregates are obtained by the extraction from natural sources in quarries. The remaining part of the aggregates originate from the recycled materials, and a smaller quantity is obtained by using extraction in water; and as secondary product of some industrial processes.
A large part of all waste produced by the mankind is construction waste. This kind of waste can be reused without processing, or reprocessing and then reused in a different manner. One of the final goals of the recovery of construction waste is the acquisition of the recycled aggregate that is suitable for re-use. By applying appropriate processing methods, the waste loses the “status” of waste; and the material obtained by processing is considered to be construction product. As such, its use has to comply to the requirements defined in the Construction Products Regulation.
Cost Benefit Analysis (CBA) was conducted for the case of obtaining stone aggregate for use in decoupled layers from the quarry; and for the case of obtaining recycled aggregate from construction waste landfill. For this purpose, the survey of relevant Slovenian and European legislation, as well as their effects upon the production processes used for the acquisition of stone aggregate from natural / secondary sources and the operation of the landfill are first presented in details. The extraction process of natural is described as well.
The results of CBA show that from the financial point of view, the processing procedures re similar for both natural and secondary aggregates, when non-hazard materials are considered. Significant differences appear due to the payment of concession fee (for the for extraction of natural aggregates and for checking the presence of dangerous substances in earth in excavations). The conducted analysis shows that many secondary materials can be recycled and reused.
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