Composting proposed

Mandatory Food Composting Proposed, Resource Recycling, March 1998, p. 13. 

The local compostion model is developed as a symmetric model, based on pure solvent and hypothetical pure completely-dissociated liquid electrolyte. This model is then normalized by infinite dilution activity coefficients in order to obtain an unsymmetric local composition model. Finally the unsymmetric Debye-Huckel and local composition expressions are added to yield the excess Gibbs energy expression proposed in this study. 

Environmental applications of FIFFF have been carefully collected in a review by Gimbert et al. [35]. Separations of nanoparticles belong to the FIFFF tradition and this sector has recently found new, fully deserved impulse for microparticle separations. The FIFFF technique has been applied to analyze humic material and submicron Fe colloids. Coupled with ICP-MS, FIFFF has been applied to detect the major and trace element chemistry of aquatic colloids in groundwaters and to determine the trace element distribution in soil and compost-derived humic and colloidal fractions in municipal wastewater. Recently, the ICP-AES has also been proposed as a specific detector for FIFFF to analyze inorganic nanoparticles (Figure 12.12). 

Hexamethylenetetramine and cyclohexylamine are both tasteless solutions. Hexamethylenetetramine, a highly water soluble compound, is tasteless even diough it is compost of a AH-X component (Figure 1). Its molecular size is too small to exhibit the bitter taste proposed by the theory presented in Figure 1. Cyclohexamine, similarly, is tasteless. When both solutions are mixed together, a bitter flavor is exhibited. Interestingly, the bitter flavor of the mixed components is changed to sweet when acetic acid is adde (5), a fact consistent with the competitive theory. 

Domeizel, M., Khalil, A., and Prudent, P. (2004). UV spectroscopy a tool for monitoring humification and for proposing an index of the maturity of compost. Bioresour. Technol. 94,177-184. 

Many tests and criteria have been proposed in order to evaluate the maturity level of compost, but they are generally time consuming and not easy to run. The humification process and organic matter evolution can be followed with two approaches ... 

The use of UV spectrophotometry has been studied in order to evaluate the potentiality of this technique for the proposal of an index of maturity. Figure 16 shows the aqueous leachates of composts with a great difference between fresh and treated compost. 

Faced with this complexity, the proposal of a maturity index from UV spectrophoto-metric data supposes considering the evolution of the whole spectrum. The first step is the identification of the particular experimental spectra that permit explaining any other spectrum as a linear combination of these reference spectra [24]. This procedure is the semi-deterministic one, presented in Chapter 2 and already applied in the previous applications. These spectra are automatically selected from the set of a great number of spectra of raw extracts of composts (including humic and fulvic acids) or related to a gel chromatographic fraction. Four reference spectra have been selected from the spectra bank, corresponding respectively to the spectra of (Fig. 18) ... 

The composition of the basis of reference spectra and the general evolution of the coefficients are closely linked to the various states of the evolution of organic matter during composting. A maturity index can thus be proposed from the values of these coefficients. 

Figure 14.17. Example of the manual composting pilot plant JK 400 ( 10,000/unit) as proposed by Sytevom in Franche-Comte and installed in Favemey college, http //www.sytevom.org...

In composting, 12-week tests proposed by the norms do not sahsfy many composting industrialists working with methods that can obtain compost after only four weeks. Current studies are also trying to hmit the dtrrahon of the tests. 

In 1998, Portland, Oreg., became the first major U.S. city to consider mandatory food waste composting. The proposal recommended to the City Council would require participation by some grocery stores, restaurants, and food processors, but not by individual residents. The city says commercial food waste represents the largest single material in the current solid waste stream, and so it is important to target in attempts to meet the city s 60% recovery goal. ... 

The definition of compostable plastic proposed in ISO/DIS 17088 is iderrtical to that given in the ASTM D 6400 standard. 

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