Materials degradation overall cost

Corrosion (of metals) and fracture (of all materials) each amounts to approximately of the GNP in the U.S., and probably in other industrialized nations. Wear, the other degradative process of capital equipment, has not been discussed as yet. However, from the results presented in Ref. 15 and 16, it can be concluded that the application of tribology could save 1.1 to 1.5 of the GNP in the U.S. in 1971. From the definition used (16) this represents costs somewhere between avoidable costs and total costs, the reference "World being essentially the World IV of the NBS fracture study. While the subject merits further study, the results indicate that the costs of wear are roughly comparable to the costs of corrosion and fracture, but perhaps somewhat less. It can thus be concluded that the overall costs of these three degradative processes amount to somewhat more than 10 of the GNP. Costs associated with the other degradative process mentioned earlier are not known to this author, but clearly will raise this total. 

Besides a number of teehnieal challenges, amine absorption is presently eonsidered the best available teehnology for CO2 capture from power plant flue gases. Reeent publieations, however, indicate that the energy requirement for solvent reeovery might eause overall power plant efficiency losses up to 16%-points. Furthermore, ehemieal degradation requires continuous solvent replaeement leading to additional material and disposal costs. 

The overall national costs of corrosion of metal and fracture of all materials are each about of the GNP, 20-30% of which could be saved with complete use of economic best practice. The costs of wear, which are not as well known, raise the total costs of these three degradative processes to somewhat over 10% of the GNP. The costs are expected to be comparable in other industrialized nations. From the results in Ref. 18, the extra corrosion costs of metals associated with air pollution are about 0.15% of the GNP, or H% of the total corrosion costs. 

To avoid degradation of the construction materials used for the treatment unit, it has been customary to undertake cleaning after the gas has been cooled to below 100 °C, but this reduces the overall energy efficiency of the plant and increases both capital and operating costs. When using IGCC technology, the... 

In order to obtain the compostable polymer materials with the best compromise between mechanical and processing properties and cost, as well as compostability, various blends of biodegradable polymers have been studied. For example, blends such as PLA/PHA, PLA/ starch have improved performance with respect to degradation rate, permeability characteristics, and thermal and mechanical properties. Overall processability is thus improved and the range of possible applications for PLA is broadened. Blends of PLA and natural fibres have increased durability and heat resistance and resulted in a lower cost to weight ratio compared to unblended PLA [6]. 

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