Three different products were obtained from the pyrolysis of dry peel sweet orange: bio-oil, char... more Three different products were obtained from the pyrolysis of dry peel sweet orange: bio-oil, char and non-condensable gases. The yield of each product was determined. The bio-oil was characterized by GC–MS to determine that can be used as a renewable source of valuable industrial chemicals or as a source of energy, high heating value was calculated by Channiwala and Parikh correlation based on Dulong's Formula.Thermogravimetric analysis at 1, 5, 10, 20, and 40 °C/min, shows three different overlapped steps resulting in an average mass loss of ∼80% within the temperature range of 114–569 °C. The bench scale pyrolysis experiments, produces average yields of 53.1, 21.1 and 25.8 wt.% for bio-oil, char and gases, respectively. Bio-oil characterization by GC–MS and FTIR identified limonene as its main component while other identified compounds included δ-limonene, alcohols, phenols, benzene, toluene, xylene and carboxylic acids.
Thermal behavior of textile waste was studied by thermogravimetry at different heating rates and ... more Thermal behavior of textile waste was studied by thermogravimetry at different heating rates and also by semi-batch pyrolysis. It was shown that the onset temperature of mass loss is within 104–156 °C and the final reaction temperature is within 423–500 °C. The average mass loss is 89.5%. There are three DTG peaks located at the temperature ranges of 135–309, 276–394 and 374–500 °C, respectively. The first two might be associated with either with decomposition of the hemicellulose and cellulose or with different processes of cellulose decomposition. The third peak is possibly associated to a synthetic polymer. At a temperature of 460 °C, the expected amount of volatiles of this waste is within 85–89%. The kinetic parameters of the individual degradation processes were determined by using a parallel model. Their dependence on the heating rate was also established. The pyrolysis rate is considered as the sum of the three reaction rates. The pyrolysis in a batch reactor at 700 °C and nitrogen flow of 60 ml/min produces 72 wt.% of oil, 13.5 wt.% of gas and 12.5 wt.% of char. The kinetic parameters of the first peak do not vary with heating rate, while those of the second and the third peak increase and decrease, respectively, with an increasing heating rate, proving the existence of complex reaction mechanisms for both cases.
Vacuum pyrolysis of individual plastics including high density polyethylene (HDPE), low density p... more Vacuum pyrolysis of individual plastics including high density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene (PP) and polystyrene (PS) has been performed at a final temperature of 500°C and under a total pressure of 2 kPa. A PVC sample and a commingled plastic sample composed of HDPE/LDPE/PP/PS/PVC have been pyrolyzed in two consecutive steps at 360 and 520°C in order to separately trap HCl. A pyrolysis set-up consisting of a bench scale batch reactor with a condensation train was used to collect the pyrolysis products. The main gaseous and liquid products, including the chlorinated hydrocarbons, were identified by chromatography. Global and chlorine mass balances were performed. The yields and pyrolysis product composition from each single polymer were compared with those from the commingled plastics. At 520°C, 99.55 wt.% of the total chlorine was trapped as HCl corresponding to 4.6 wt.% in yield, on an original feedstock basis, followed by 62.0 wt.% wax, 31.1 wt.% oil, 1.0 wt.% gas and 1.2 wt.% solid char residue (loss was 0.1 wt.%). The pyrolysis oil contained 12 ppm Cl on a pyrolysis oil basis. This value was less than what was expected (153 ppm) from the theoretical values which were calculated when the individual polymers were pyrolysed. The chlorinated hydrocarbons formed during the pyrolysis of commingled plastics were different from those obtained during the thermal decomposition of pure PVC. However, the hydrocarbons produced in the oil fraction were similar to those identified during the pyrolysis of the single plastics.
A new method, called the DTG curve fitting method, has been used to determine the kinetic paramet... more A new method, called the DTG curve fitting method, has been used to determine the kinetic parameters of six major plastic materials found among urban refuse: high-density polyethylene, low-density polyethylene, polystyrene, polypropylene, poly(vinyl chloride), and poly(ethylene terephthalate). This method involves first measuring the weight loss behaviour by using thermogravimetry (TG) and then using the Arrhenius equation to fit the DTG curves obtained from the TG measurement. The kinetic parameter data obtained have been compared to, and agree well, with the literature data. With this method, computer software, named “DTGsim” has been developed, for use under Windows with a user friendly interface.
International Journal of Chemical Reactor Engineering, 2008
Abstract Peirce-Smith converters (PSC) are chemical reactors where copper matte reacts with air. ... more Abstract Peirce-Smith converters (PSC) are chemical reactors where copper matte reacts with air. A conventional PSC is a long horizontal cylinder where air is injected laterally into the cooper bath through submerged tuyeres. In these PSC, air is injected at high velocities ...
ABSTRACT In order to analyze the influence of a third phase in the behaviour of the free surface ... more ABSTRACT In order to analyze the influence of a third phase in the behaviour of the free surface profile in the mould of a slab steel continuous caster, multiphase flow in a mould water model is physically and numerically investigated. A one third scale mould water model was constructed in accordance with the Froude similarity criterion. The free surface profile in the experimental air-water system was tracked using ultrasonic level sensors which were located at six different positions along a line between the submerged entry nozzle and the mould narrow wall. Volumetric flow rates of water from 3.5×10-4 to 5.83×10-4 m3 /s were employed in the physical experiments. Three submergence depths of the nozzle, namely 0.05, 0.07 and 0.09 m, were considered. On the other hand, two and three phase transient and steady state numerical simulations were carried out by means of computational fluid dynamics software. Oil engine was employed as the third phase in the numerical simulations. A comparison between the experimental results and the numerical ones with three phases suggests significant changes in the steel-slag interface due to the presence of the third phase, particularly in the neighbourhood of the discharge of the submerged entry nozzle.
A priori design of catalysts is not yet possible. Such task would demand unavailable scientific k... more A priori design of catalysts is not yet possible. Such task would demand unavailable scientific knowledge of the correlations among synthesis parameters and resulting solid state and surface structures, on the one hand, and among those atomic-level structural ...
International Journal of Chemical Reactor Engineering, 2000
Abstract Peirce-Smith converters (PSC) are chemical reactors where copper matte reacts with air. ... more Abstract Peirce-Smith converters (PSC) are chemical reactors where copper matte reacts with air. A conventional PSC is a long horizontal cylinder where air is injected laterally into the cooper bath through submerged tuyeres. In these PSC, air is injected at high velocities ...
Three different products were obtained from the pyrolysis of dry peel sweet orange: bio-oil, char... more Three different products were obtained from the pyrolysis of dry peel sweet orange: bio-oil, char and non-condensable gases. The yield of each product was determined. The bio-oil was characterized by GC–MS to determine that can be used as a renewable source of valuable industrial chemicals or as a source of energy, high heating value was calculated by Channiwala and Parikh correlation based on Dulong's Formula.Thermogravimetric analysis at 1, 5, 10, 20, and 40 °C/min, shows three different overlapped steps resulting in an average mass loss of ∼80% within the temperature range of 114–569 °C. The bench scale pyrolysis experiments, produces average yields of 53.1, 21.1 and 25.8 wt.% for bio-oil, char and gases, respectively. Bio-oil characterization by GC–MS and FTIR identified limonene as its main component while other identified compounds included δ-limonene, alcohols, phenols, benzene, toluene, xylene and carboxylic acids.
Thermal behavior of textile waste was studied by thermogravimetry at different heating rates and ... more Thermal behavior of textile waste was studied by thermogravimetry at different heating rates and also by semi-batch pyrolysis. It was shown that the onset temperature of mass loss is within 104–156 °C and the final reaction temperature is within 423–500 °C. The average mass loss is 89.5%. There are three DTG peaks located at the temperature ranges of 135–309, 276–394 and 374–500 °C, respectively. The first two might be associated with either with decomposition of the hemicellulose and cellulose or with different processes of cellulose decomposition. The third peak is possibly associated to a synthetic polymer. At a temperature of 460 °C, the expected amount of volatiles of this waste is within 85–89%. The kinetic parameters of the individual degradation processes were determined by using a parallel model. Their dependence on the heating rate was also established. The pyrolysis rate is considered as the sum of the three reaction rates. The pyrolysis in a batch reactor at 700 °C and nitrogen flow of 60 ml/min produces 72 wt.% of oil, 13.5 wt.% of gas and 12.5 wt.% of char. The kinetic parameters of the first peak do not vary with heating rate, while those of the second and the third peak increase and decrease, respectively, with an increasing heating rate, proving the existence of complex reaction mechanisms for both cases.
Vacuum pyrolysis of individual plastics including high density polyethylene (HDPE), low density p... more Vacuum pyrolysis of individual plastics including high density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene (PP) and polystyrene (PS) has been performed at a final temperature of 500°C and under a total pressure of 2 kPa. A PVC sample and a commingled plastic sample composed of HDPE/LDPE/PP/PS/PVC have been pyrolyzed in two consecutive steps at 360 and 520°C in order to separately trap HCl. A pyrolysis set-up consisting of a bench scale batch reactor with a condensation train was used to collect the pyrolysis products. The main gaseous and liquid products, including the chlorinated hydrocarbons, were identified by chromatography. Global and chlorine mass balances were performed. The yields and pyrolysis product composition from each single polymer were compared with those from the commingled plastics. At 520°C, 99.55 wt.% of the total chlorine was trapped as HCl corresponding to 4.6 wt.% in yield, on an original feedstock basis, followed by 62.0 wt.% wax, 31.1 wt.% oil, 1.0 wt.% gas and 1.2 wt.% solid char residue (loss was 0.1 wt.%). The pyrolysis oil contained 12 ppm Cl on a pyrolysis oil basis. This value was less than what was expected (153 ppm) from the theoretical values which were calculated when the individual polymers were pyrolysed. The chlorinated hydrocarbons formed during the pyrolysis of commingled plastics were different from those obtained during the thermal decomposition of pure PVC. However, the hydrocarbons produced in the oil fraction were similar to those identified during the pyrolysis of the single plastics.
A new method, called the DTG curve fitting method, has been used to determine the kinetic paramet... more A new method, called the DTG curve fitting method, has been used to determine the kinetic parameters of six major plastic materials found among urban refuse: high-density polyethylene, low-density polyethylene, polystyrene, polypropylene, poly(vinyl chloride), and poly(ethylene terephthalate). This method involves first measuring the weight loss behaviour by using thermogravimetry (TG) and then using the Arrhenius equation to fit the DTG curves obtained from the TG measurement. The kinetic parameter data obtained have been compared to, and agree well, with the literature data. With this method, computer software, named “DTGsim” has been developed, for use under Windows with a user friendly interface.
International Journal of Chemical Reactor Engineering, 2008
Abstract Peirce-Smith converters (PSC) are chemical reactors where copper matte reacts with air. ... more Abstract Peirce-Smith converters (PSC) are chemical reactors where copper matte reacts with air. A conventional PSC is a long horizontal cylinder where air is injected laterally into the cooper bath through submerged tuyeres. In these PSC, air is injected at high velocities ...
ABSTRACT In order to analyze the influence of a third phase in the behaviour of the free surface ... more ABSTRACT In order to analyze the influence of a third phase in the behaviour of the free surface profile in the mould of a slab steel continuous caster, multiphase flow in a mould water model is physically and numerically investigated. A one third scale mould water model was constructed in accordance with the Froude similarity criterion. The free surface profile in the experimental air-water system was tracked using ultrasonic level sensors which were located at six different positions along a line between the submerged entry nozzle and the mould narrow wall. Volumetric flow rates of water from 3.5×10-4 to 5.83×10-4 m3 /s were employed in the physical experiments. Three submergence depths of the nozzle, namely 0.05, 0.07 and 0.09 m, were considered. On the other hand, two and three phase transient and steady state numerical simulations were carried out by means of computational fluid dynamics software. Oil engine was employed as the third phase in the numerical simulations. A comparison between the experimental results and the numerical ones with three phases suggests significant changes in the steel-slag interface due to the presence of the third phase, particularly in the neighbourhood of the discharge of the submerged entry nozzle.
A priori design of catalysts is not yet possible. Such task would demand unavailable scientific k... more A priori design of catalysts is not yet possible. Such task would demand unavailable scientific knowledge of the correlations among synthesis parameters and resulting solid state and surface structures, on the one hand, and among those atomic-level structural ...
International Journal of Chemical Reactor Engineering, 2000
Abstract Peirce-Smith converters (PSC) are chemical reactors where copper matte reacts with air. ... more Abstract Peirce-Smith converters (PSC) are chemical reactors where copper matte reacts with air. A conventional PSC is a long horizontal cylinder where air is injected laterally into the cooper bath through submerged tuyeres. In these PSC, air is injected at high velocities ...
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