Thermal Decomposition of Mobile Phones

Paper submitted to the 31st International Symposium on Halogenated Persistent Organic Compounds (Dioxin 2011), Brussels, Belgium, 21-25 August 2011.

Saint Mathew Law and Bonini Paradox in Textual Theory of Complex Models

The mathematical models of the complex reality are texts belonging to a certain literature that is written in a semi-formal language, denominated L(MT) by the authors whose laws linguistic mathematics have been previously defined. This text possesses linguistic entropy that is the reflection of the physical entropy of the processes of real world that said text describes. Through the temperature of information defined by Mandelbrot, the authors begin a text-reality thermodynamic theory that drives to the existence of information attractors, or highly structured point, settling down a heterogeneity of the space text, the same one that of ontologic space, completing the well-known law of Saint Mathew, of the General Theory of Systems and formulated by Margalef saying: “To the one that has more he will be given, and to the one that doesn't have he will even be removed it little that it possesses.

Study of the emissions from pyrolytic and oxidative thermal decomposition of PVC

Polyvinyl chloride (PVC) is one of the plastics most extensively used due to its versatility. The demand of PVC resin in Europe during 2012 reached 5000 ktonnes1. PVC waste management is a big problem because of the high volume generated all over the world and its chlorine content. End-of-life PVC is mainly mixed with municipal solid waste (MSW) and one common disposal option for this is waste-to-energy incineration (WtE). The presence of plastics such as PVC in the fuel mix increases the heating value of the fuel. PVC has two times higher energy content than MSW ‒around 20 MJ/kg vs 10 MJ/kg, respectively. However, the high chlorine content in PVC resin, 57 wt.%, may be a source for the formation of hazardous chlorinated organic pollutants in thermal processes. Chlorine present in the feedstock of WtE plants plays an important role in the formation of (i) chlorine (Cl2) and (ii) hydrochloric gas (HCl), both of them responsible for corrosion, and (iii) chlorinated organic pollutants2. In this work, pyrolytic and oxidative thermal degradation of PVC resin were carried out in a laboratory scale reactor at 500 ºC in order to analyze the influence of the reaction atmosphere on the emissions evolved. Special emphasis was put on the analysis of chlorinated organic pollutants such as polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs) and other related compounds like polychlorobenzenes (PCBzs), polychlorophenols (PCPhs) and polycyclic aromatic hydrocarbons (PAHs). Another objective of this work was to compare the results with those of a previous work3 in which emissions at different temperatures in both pyrolysis and combustion of another PVC resin had been studied; in that case, experiments for PCDD/Fs emissions had been performed only at 850 ºC.

The combined effect of plastics and food waste accelerates the thermal decomposition of refuse-derived fuels and fuel blends

Mechanical treatments such as shredding or extrusion are applied to municipal solid wastes (MSW) to produce refuse-derived fuels (RDF). In this way, a waste fraction (mainly composed by food waste) is removed and the quality of the fuel is improved. In this research, simultaneous thermal analysis (STA) was used to investigate how different mechanical treatments applied to MSW influence the composition and combustion behaviour of fuel blends produced by combining MSW or RDF with wood in different ratios. Shredding and screening resulted in a more efficient mechanical treatment than extrusion to reduce the chlorine content in a fuel, which would improve its quality. This study revealed that when plastics and food waste are combined in the fuel matrix, the thermal decomposition of the fuels are accelerated. The combination of MSW or RDF and woody materials in a fuel blend has a positive impact on its decomposition.

Thermogravimetric and kinetic analysis of the decomposition of solid recovered fuel from municipal solid waste

The thermal decomposition of a solid recovered fuel has been studied using thermogravimetry, in order to get information about the main steps in the decomposition of such material. The study comprises two different atmospheres: inert and oxidative. The kinetics of decomposition is determined at three different heating rates using the same kinetic constants and model for both atmospheres at all the heating rates simultaneously. A good correlation of the TG data is obtained using three nth-order parallel reactions.