RESUMEN
The aim of this study is to present the optimum operating conditions for reducing energy consumption in the process of obtaining bio-oil from the mixture of sawdust, waste lubricating oil, lime, and commercial catalyst. In the study where the catalytic pressureless depolymerisation (also called Katalytische Drucklose Verölung - KDV) was applied, the operating conditions were analysed with response surface methodology. According to the analysis of variance results, a mathematical model was obtained for specific product yield (bio-oil amount/energy consumption g kWe-1). Effects of temperature (260°C-290°C), catalyst rate (1-2 wt.%) and reaction time (0.5-1 h) were investigated. The optimum conditions for the three independent variables (temperature, catalyst rate, reaction time) were 279 ± 2°C, 2 wt.% and 0.5 h, respectively. Maximum specific product yield was obtained as 970.17 g kWe-1. While the reaction time was the most effective regarding the amount of bio-oil obtained at 1 kWe energy consumption, the temperature was found to be the least effective. In addition to these, bio-oil obtained under optimum conditions were characterised and compared with standard diesel specifications.
Asunto(s)
Biocombustibles , Madera , Biomasa , Catálisis , Calor , TemperaturaRESUMEN
In this study, the production of bio-oil from the pyrolysis of furniture sawdust, waste lubricating oil and their mixtures were investigated under certain operating conditions in the presence of lime and zeolites, by using a laboratory scale horizontal tubular reactor placed in a furnace. The main focus was to investigate the mutual effect of lime and commercial zeolite on the amount of the bio-oil production from furniture sawdust and waste lubricating oil. The selected operating parameters were pyrolysis temperatures and heating rate of 300°C and 650°C and flash heating or gradual heating rate (30°C/min). Additionally, three different additives were tested as catalysts; namely, lime (CaO), commercial zeolite (4A) and a natural zeolite (klinoptilolite). The amount of the produced bio-oil was analyzed by gas chromatography-flame ionization detector. The distribution of solid, liquid and gaseous products was determined for each operational condition. It was seen that the amount of the bio-oil was influenced by the amounts of sawdust and zeolite in the mixture. Experimental results showed that higher temperatures were more effective for the higher bio-oil amount. Additionally, heating rate was quite significant at 300°C whereas it has a minor effect on the bio-oil amount at 650°C. The highest bio-oil yield was obtained for the mixture of sawdust and waste lubricating oil in the presence of both lime and commercial zeolite with flash heating rate at 650°C.
Asunto(s)
Aceites de Plantas , Polifenoles , Biocombustibles , Biomasa , Calor , MaderaRESUMEN
Hair-thread tourniquet syndrome is an emergency condition rarely encountered since its first description, and it may be potentially dangerous unless treated. The potential hazard of the condition stems from hair strands wrapping around and strangulating various body processes such as fingers, penis, or clitoris. In this paper we aimed to report the first case of hair-thread tourniquet syndrome affecting a haemangioma of an adult patient. A 68-year-old woman presented to emergency department for pain in the mass on her back. On physical examination, a haemangioma with a size of about 3x3 cm was noted on the right scapula. When inspected closely, it appeared edematous and strangulated, and there were hair strands wrapped to the bottom of the wound. The hair strands were removed and the strangulated haemangioma was excised.