Targeted treatment solutions

Figure 32.1 Targeted treatment solutions. Reproduced with permission from Threshold of Innovation (2005). IBM Business Consulting Services [1]. See color plate.

The technology developer, Atomic Energy of Canada Limited (AECL), has compiled cost estimates (in 1994 U.S. dollars) for the CHEMIC process based on treatment of a simulated waste solution contaminated with metals (cadmium and lead at feed concentrations from 1 to 5 mg/liter) and strontium-90 [from 1000 to 2000 becquerel per liter (Bq/liter)]. The target treatment level is <0.014 mg/liter lead, <0.02 mg/liter cadmium, and <10 Bq/liter strontium-90. See Table 1 for estimates associated with this cost analysis. The AECL analysis indicated that costs of the CHEMIC process compared favorably with the estimated costs for treatment using reverse osmosis or fixed-bed ion exchange. 

The determination of the weight of toxic organic compound adsorbed per unit mass of activated carbon QUm), for the three organic compounds at the three aforementioned concentrations is illustrated m Tables C to CXXVI. For each isotherm, X/m was dependent upon the tai eted treatment level. Two targeted treatment concentrations (TOC readings) of 5 mg/l and 50 mg/1 were used throughout from Tables C to CXXVI. For the BET isotherm, the saturated concentration of solute values, Cs, of 65 mg/1,195 mg/I and 325 mg/1 were used for o anic compound concentrations of 100 mg/1,300 mg/1 and 500 mg/1 respectively. 

In summary, although clear, light-colored cellulose solutions are required to start the synthesis, there is no guarantee, a priori, that the targeted DS will be obtained. The reasons are that the state of aggregation of cellulose is dependent on the structural characteristics of the starting material, is sensitive to the pre-treatment employed, and the impurities present. This may result in non-reproducible aggregation states, and may lead to oscillation in cellulose reactivity. Typically, effects of these oscillations may not be readily apparent, because ... 

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