Calorific power

The waste from the separation is called waste-derived fuel (WDF) or solid recovered fuel (SRF). It is normally composed of materials with good calorific power, such as paper, plastics, fabrics, and wood. These materials are only the rejects that cannot be recycled, due mainly to the level of contaminants they contain. 

According to [4], two coincineration routes can be utilized with good energy recovery coincineration in coal-fired thermoelectric plants and coincineration in cement furnaces to replace fossil fuels, which in the Brazilian case is generally petroleum coke (petcoke). The substitution in power plants is up to 10% and in cement plants up to 30% by weight. The calorific power of the SRF in the study by [4] is 18 MJ/kg or 4,300 kcal/kg, which corresponds to 6% of the calorific power of coal. 

The waste materials from the separation process are prepared for coprocessing by a contracted firm. Different tests are carried out on the waste material at the Lafarge laboratories to control the calorific power, ash production, and presence of chlorides. These characteristics are extremely important for successful coprocessing [6]. An example of the trends of the results of these tests is shown in Fig. 9. 

The average calorific power of the material received for coprocessing, which in August 2010 was 3,898 kcal/kg, increased to 5,495 kcal/kg in September that year. The average ash content fell from 14.09% in August 2010 to 8.46% in the following month, while the concentration of chlorides fell from 1.02% to 0.37% in the same period. 

Since the concentration of chlorides is associated with the presence of plastics, it can be concluded that in August there was more plastic material from the separation process, which also led to a lower calorific power and higher ash content after burning. In this respect, according to [6], the level of chlorides also depends on the type of plastic. 

Table 2 presents the results of tests to measure the calorific power, ash content, and chlorides concentration of some of the materials obtained from the separation process, such as polystyrene, aluminum foil, plastic foam, and other plastics (general, clear, colored, black, and vinyl). Polystyrene and clear plastic have very high calorific power and low levels of chlorides, but polystyrene has very high ash content. Figures 10-17 present the samples of waste components from the separation and composting plant of Cantagalo. 

The results of the tests to determine the calorific power show satisfactory values for coprocessing, be it for mixed materials, otherwise unusable material from separation or plastics in general. As observed by [6], the level of chlorides is closely related to the quantity of plastics in the mixture, and also depends on the type of plastic. 

There is a need for further studies of the calorific power, ash content, and level of chlorides in waste materials for coprocessing in the cement industry or for incineration to generate energy (WTE), considering the variability of the wastes produced at different times of the year and by different populations, as shown by the test results. 

Now, whatever purpose water gas may be required r, its use for this purpose depends on the fact that the IS will combine with oxygen with the evolution of ia.t, consequently the plant should be worked to make e product with the highest calorific power for the west fuel consumption. This requirement is reached ore closely if the plant is operated so that the first nation represents the chemical reaction which takes ice , consequently, in the practical manufacture of water s the coke or other fuel in the gas producer should at a temperature of about 1000° C. 

If 35 lb. of the coke, the analysis of which has been already given, are consumed in the production of looo cubic feet of water gas at 30 inches barometer and 60° F., of the composition which has also been given, it will be found that the calorific power of the coke consumed, compared with that of the gas produced, is as... 

A variety of parameters are commonly measured on coals, such as elemental composition (C, H, O, N, S), content of ash, moisture, as well as physical properties such as calorific power, hardness, and reflectance. These parameters have a wide range of values, and only some ranges can be indicated. For example, the elemental composition (in ash free coals) is 85-92 % C, 2-3% H, and 7-8% O for anthracite, 70-75% C, 5-6% H, and 15-20% O for bituminous coals, and 55-70% C, 6-7% H, and 25-30% O for lignites. Coal may also contain 1-2% N, and up to 4-5% or even higher of S. The content of ash can also vary from a few percent to 20% or higher. 

Ej is the electric potential at the current density j Q is the calorific power... 

In the case of Q, we have to introduce the thermodynamic properties, AG as —nFEj, and considering that AG = AH — TAS, we can obtain the calorific power as... 

In energy terms, industries of sugar and alcohol are sustainable, in which about 90% bagasse (calorific power 18.322 kJ kg ) is used however, the consumption can be reduced for 70% if the system of steam generation was optimized. Straw can also be mixed to the bagasse to be burned because of high calorific power (18.870 kJ kg ) [2] but with the drawback of producing more ashes. 

Smitheries were excluded from the scope of the document since no European smitheries were reported which meet the conditions stated in Aimex I 2.3 (b), i.e. Smitheries with hammers the energy of which exceeds 50 kJ per hammer, (and) where the calorific power used exceeds 20 MW . Accordingly, cadmium, titanium and precious metals foundries, as well as bell and art casting foundries were excluded on capacity grounds. 

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