Читать книгу Industrial Environmental Management - Tapas K. Das - Страница 38

One critical component of the industrial ecology paradigm is dematerialization. Dematerialization means using less material to make products that perform the same function as predecessors. Sometimes this means smaller or lighter products, but other aspects can include increasing the lifetime of a product or its efficiency. The net effect is a reduction in overall resource extraction. Dematerialization is thus a way to increase the percentage of active materials embodied in durables, and to reduce the percentage that is left as waste residuals.

However, dematerialization has limits in achieving Zero Emissions. We may also need to think of rematerialization – products that may or may not have a lighter weight in their final form, but whose production, use, and subsequent conversion or recyclability fits within the Zero Emissions paradigm. This is demonstrated by the ease and benefit of recycling older model cars versus the newer ones. Nonetheless, economists and engineers point out that optimizing for environmental protection alone means some loss in safety, efficiency, durability, convenience, attractiveness, and price.

Figure 1.7 Metals‐specific Sherwood plot for waste streams: minimum concentration of metal wastes undergoing recycling versus metal prices.

Source: From Johnson et al. (2007). American Chemical Society.

Figure 1.8 A Sherwood diagram showing the correlation between the selling price of materials and their degree of dilution in the matrix from which they are separated.