• Energy Research
• 12. Responsible consumption close

Abstract The elevated energy demands from past decades has created the energy gaps which can mainly be fulfilled through the consumption of natural fossil fuels but at the expense of increased greenhouse gas emissions. Therefore, the need of clean and sustainable options to meet energy gaps have increased significantly. Gasification and steam methane reforming are the efficient technologies which resourcefully produce the syngas and hydrogen from coal and natural gas, respectively. The syngas and hydrogen can be further utilized to generate power or other Fischer Tropsch chemicals. In this study, two process models are developed and technically compared to analyze the production capacity of syngas and hydrogen. First model is developed based on conventional entrained flow gasification process which is validated with data provided by DOE followed by its integration with the reforming process that leads to the second model. The integrated gasification and reforming process model is developed to maximize the hydrogen production while reducing the overall carbon dioxide emissions. Furthermore, the integrated model eradicates the possibility of reformer’s catalyst deactivation due to significant amount of H2S present in the coal derived syngas. It has been seen from results that updated model offers 37% increase in H2/CO ratio, 10% increase in cold gas efficiency (CGE), 25% increase in overall H2 production, and 13% reduction in CO2 emission per unit amount of hydrogen production compared to base case model. Furthermore, economic analysis indicated 8% reduction in cost for case 2 while presenting 7% enhanced hydrogen contents.

Abstract Since decades, one of the major troublesome environmental issue to the society is Polystyrene waste. Thermal conversion method can be used to transform the plastic waste into useful energy source. In this study, liquefaction technique using ethanol as a solvent was used to produce liquid fuel from polystyrene. The experiments were performed at different temperatures (290–370 °C), ethanol to polystyrene ratios (0.25:1–4:1) and reaction times (15–75 min) in an autoclave batch reactor. After characterization, quantitative and qualitative evaluation of liquid products; results showed that at temperature of 350 °C, ethanol to polystyrene ratio of 0.5:1 and reaction time of 60 min, highest liquid yield of 84.7 wt% was achieved. The viscosity, density, pH, calorific value and flash point of the oil product at this condition was 0.36 cP, 0.88 g/mL, 6.86, 40.91 MJ/kg and 55 °C respectively. Through GC–MS analysis, it was found that the oil product was mostly composed of aromatics, alkenes and alkyls; which made the liquid oil suitable to be used as fuel. In addition, comparative study was conducted by replacing ethanol with water as solvent under same conditions. Based on results, study proved ethanol to be better solvent than water which is commonly used in liquefaction process. Lastly, the liquid fuel produced is suitable to be used as alternative energy source for conventional fossil fuels.