توصيفگر ها :
پيروليز , زيست توده , كوپيروليز , پارافين سنگين مايع , پارافين وكس
چكيده انگليسي :
Nowadays, consumption of non-renewable energy sources such as fossil fuels has caused many environmental problems. Therefore, research on renewable energy sources that can solve these problems has increased. Biomass is one of the abundant sources of renewable energy in the world. Due to the abundance and variety of biomass resources, many methods have been invented to convert biomass into energy and chemicals, one of these methods is pyrolysis. In pyrolysis, biomass containing organic matter is heated in the absence of oxygen and at high temperature, and its condensable volatiles are collected as the main product. In addition to being used as a fuel, this product contains a wide range of high-value organic substances that can be separated in refining processes. In this research, the aim is to investigate the pyrolysis of corn cob as the studied biomass. At first, corn cob was measured by approximate analysis and ultimate analysis methods, and the amount of moisture, volatile matter, ash and fixed carbon as well as elements of carbon, hydrogen, nitrogen, oxygen and sulfur were measured, then the effect of factors such as, temperature, carrier gas flow rate And the residence time of the corn cob in the reactor was investigated on the mass yield of the products and it was found that at a temperature of °C, a time of minutes and a carrier gas flow rate of lit/min of nitrogen gas, the highest yield of the liquid product, bio oil, was %. Then, using gas chromatography-mass spectrometer analysis, it was determined that the major compounds in bio-oil include alcohols, phenols, furans, ketones, and carboxylic acids. In examining the effect of temperature as the most influential factor on the distribution of bio-oil compounds, it was found that the increase in temperature causes a decrease in carboxylic acids and the amount of water produced, and this decrease in the amount of carboxylic acids was confirmed by observing the increasing trend in the pH of bio-oil. It was also found that increasing the pyrolysis temperature increases the amount of phenols and furans, while ketones and alcohols are at their maximum at °C. Further, in order to investigate the effect of copyrolysis on the yield and composition of bio-oil, copyrolysis was performed with heavy liquid paraffin and the results showed that copyrolysis of a mixture of paraffin and corn cob at has the highest y and synergistic effect. Also, in order to investigate the effect of paraffin wax co-pyrolysis, the RFCC or Residue Fluid Catalytic Cracking catalyst was used in catalytic co-pyrolysis, and the experiments showed that the effect of the catalyst in pyrolysis alone reduces the yield of bio-oil, while the catalytic pyrolysis of paraffin wax has a positive effect. It is based on bio oil efficiency and also the highest efficiency of catalytic copyrolysis was obtained in % paraffin wax and % corn cob and the ratio of catalyst to feed was . Comparison between pyrolysis at °C and coprolysis of liquid paraffin and catalytic copyrolysis of paraffin wax showed that the amount of ketones, hydrocarbons, carboxylic acids in catalytic copyrolysis, furans, phenols in copyrolysis with liquid heavy paraffin and alcohols in pyrolysis are the highest compared to others.
