Solid fuel from mixed

Mixed solid waste 4830 Encyclopedia of Chemical Technology, Fuels from Waste, Vol. 11. 

The complexity of the thermochemical conversion of solid fuels is obvious when we go from the level of the single particle up to the level of the heterogeneous mixed bed system, see Figure 31. The more complex the conversion system becomes, the more differentiated the conceptual model, and hence the mathematical model, needs to be. 

Anaerobic digestion to methane, on-site combustion, mixing with coal to form solid fuel Direct combustion, can utilize carbon dioxide from industrial flue gas, can grow in municipal waste facilities... 

J. Taylor and Sillitto found that ammonium nitrate mixed with 3% of potassium chromate or bichromate undergoes spontaneous decomposition ( burning ) on being heated to about 400°C. J. Taylor et al. [5, 27] suggest utilizing mixtures made from ammonium nitrate and potassium chromate as the main component of rocket solid fuels. This is described in more detail in Vol. III. 

The most significant improvement came in the early 1940s when a method for preparing thiol-terminated liquid polysulfides was developed. Cure of the liquid polysulfides could be accomplished by oxidative coupling. Thus, in effect, a mbber could be compounded without the need of heavy mixing equipment. One of the first large-scale applications of the liquid polysulfides was as a binder for solid rocket fuel. From about 1946 until 1958, these binders were used in various rocket systems and the aliphatic polysulfides achieved commercial success. The switch to predominately liquid-fueled rockets in 1958 ended this phase of the polysulfide business. 

Since publication of this work, Japanese researchers have undertaken an effort to demonstrate the feasibility of direct dissolution of U02 from spent nuclear fuels by the TBP-HN03 complex in SC-C02.49 Ultimately, the project is directed at the extraction of both uranium and plutonium from mixed oxide fuels and from irradiated nuclear fuel. Ideally, soluble uranyl and plutonium nitrate complexes will form and dissolve in the C02 phase, leaving the FPs as unwanted solids. As in the conventional... 

Almost 80% of our present energy mix comes from fossil fuels the rest is renewable and nuclear energy. In Fig. 2, the biomass contribution is summarised among the solid fuel share, together with coal. Today, biomass still contributes about 10% to the world primary energy supply commercially traded firewood amounts to almost half of this share. 

When producing hydrogen as the final product, impurities such as CO, sulfur compounds, and other trace contaminants must be removed, particularly for application in fuel cells. Currently, pressure swing adsorption (PSA) is commonly used for the separation and purification of hydrogen from mixed gas streams. PSA systems are based on selective adsorbent beds. The gas mixture is introduced to the bed at an elevated pressure and the solid adsorbent selectively adsorbs certain components of the gas mixture, allowing the unadsorbed components, in this case hydrogen, to pass through the bed as purified gas. 

Recovery of transuranium elements is mainly of interest for solid waste from the refabrication of mixed-oxide fuel. Plutonium is the major element to be recovered, and Am may be recovered as a by-product. Other transuranium elements are usually present in minor quantities. The treated wastes are seldom decontaminated to levels of plutonium that would permit unrestricted release. 

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