Fuel valorization

According to the principle of indirect heating, the pyrohtic gases are not diluted by nitrogen or by combustion products. Tables 10.26 and 10.27 give some examples of refuse-derived fuels obtained by pyrolysis of different waste streams [80]. 

Product yields from mixed plastics pyrolysis are about 2.9% char, 75.1% oils and 9.6% noncondensable gas [16,48]. Calorihc values of the oils are about 40 MJ/kg. 

Waste Gas H- oils (kg/t) Char (% ashes) (kg/t) Metals and minerals (kg/t) 

The gasification of the char issued from the pyrolysis of different waste streams is shown in Table 10.28. From the ash content of the char, it is possible to evaluate the quantity of syngas produced by steam gasification of the chars issued from the pyrolysis of the different waste streams. The combination of the syngas and the pyrolytic gases allows evaluation of the total potential energy recovered by gasification. 

It can be seen that a significant proportion of the energy content of the waste is recovered by the gasification of the char and that the ultimate residue is decreased in comparison with the quantity of bottom ash produced compared with direct incineration. Solid plastic waste represents a significant stream for conversion back to energy [89]. 

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N. Tanchoux, F. Fajula, Bioethanol valorization for incorporation in diesel fuel blends, Prepr. Symp. — Am. Chem. Soc., Div. Fuel Chem., 51 (2006) 434. 

J. M. Arandes, J. Erena, M. J. Azkoiti, D. Lopez-Valerio and J. Bilbao Valorization by thermal cracking over silica of polyolefins dissolved in LCO Fuel Processing Technology, 85, 125 (2004). 

The quality of the gases and oils has to be certified by analytical tests in order to be accepted for valorization as substitutions fuels [5]. 

From an economic point of view, used plastic can be considered as both an important source of valuable chemicals, mainly hydrocarbons, and an energy source. The calorific value of most plastics is similar to that of fuel oils and higher than that of coals. Plastic wastes can therefore be viewed as potential fuels, when other alternatives of valorization are not possible.9... 

Graduate engineer of the Ecole Nationale Superieure des Industries Chimiques and Doctor of Philosophy, Guy-Marie COME is a Professor at the Universite Henri Poincare (Nancy I). In the Departement de Chimie Physique des Reactions, Unite Mixte Associee au CNRS, at the INP of Lorraine (ENSIC) and at The University of Nancy, he conducts research carried out within the framework of European and national research programmes and of industrial contracts with major firms. More particularly this research has been carried out within the scope of the valorization of natural gas, the reformulation of petrol and diesel fuel for limiting the production of pollutants and computational kinetics for generating more and more complex models on a computer. Guy-Marie COME s book is a synthesis of multidisciplinary elements which contribute to the comprehension of gas-phase thermal reactions. 

S.G. Howell, A ten year review of plastics recycling. J. Hazard. Mater. 29(2), 143-164 (1992) E. Butler, G. Devlin, K. McDonnell, Waste polyolefins to liquid fuels via pyrolysis review of commercial state-of-the-art and recent laboratory research. Waste Biomass Valorization 2(3), 227-255 (2011)... 

Valorization of waste compounds into high-value products. In this field, some remarkable examples are the chemical recycling of polyolefins and biomass conversion by means of catalytic processes to yield fuels and chemicals in both... 

For example, in a (thermochemical) biorefinery, biomass is converted into energy carriers such as transportation fuels (e.g., ethanol), heat, and power and/or chemicals. In terms of energy content, the amount of biomass for (transportation) fuels and CHP (e.g., by combustion) is much higher than the amount used for the production of chemicals. However, in terms of added value, chemicals can provide a significant contribution to the overall cost effeaiveness of the refinery. When the main product of a biorefinery is (hemi) cellulose bioethanol, the lignin ends up in a residue that mostly is used as a fuel to generate heat. The economics of the biorefinery will benefit much from the valorization of this lignin-rich residue to value-added aromatic chemicals. 

Aresta M, Dibenedetto A, Angelini A (2014) Catalysis for the valorization of exhaust carbon from CO2 to chemicals, materials, and fuels. Technological use of CO2. Chem Rev 114 (3) 1709-1742... 

The thermodynamic stability of CO2 requires high energy substances or electroreductive processes for its transformation into valuable chemicals in which the carbon atom has a lower oxidation state than 4 [1, 3, 4, 197]. Catalytic hydrogenation of CO2 has been acknowledged as one of the major potential steps for CO2 valorization to fuels, or other products (e.g., HCOOH, methanol, H2CO, and C1+) which are considered to be potential hydrogen carriers or useful chemicals or fuels [1, 198]. 

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