Sharif Digital Repository

Biomass's utilization provides sufficient energy which can be used for electricity generation, engine applications and etc. In gasitication process, biomass will be converted into clean and combustible gas in presence of steam and air. Biomass integrated-gasifier/gas turbine combined cycle (BIG/GTCC) systems are capable of producing up to twice as much electricity per unit of biomass consumed and are expected to have lower capital investment requirements per kilo Watt of capacity than condensing-extraction steam turbine (CEST) systems. In this Thesis thermodynamic analyses (both energy and exergy analyses) have been conducted for a combined cycle power plant, the investigated system... 

By applying the Pinch Technology and Exergoeconomic simultaneously, to a complex process system, beneficial and energy-efficient measures are identified.In the present research “Three-link-model” Exergoeconomic methodology optimizes the system and contrary to traditional exergoeconomic methods, reversed method is used. The approach proposed for optimization of such a complex system is to iteratively optimize subsystems. Since assumptions considered by conventional Exergoeconomic for calculating the cost-optimal exergetic efficiency and relative cost difference, are not applicable, new assumptions are to be considered. Unlike traditional Exergoeconomic method, product’s exergetic specific... 

Considering the increasing growth of population and the economical development in our country, the need to drinking water as well as agricultural water sources is felt more. In this respect and with regard to the lack of water sources in central and southern parts of our country, the present project suggests a system which can be used in south of the country to produce desalinated water from the salt water of sea. This system is recommended due to the comparative advantages of the southern part of the country including the prevalence of gas turbine plants, proper solar insulation and the access to salt water. The system is suggested with the presupposition of accessibility to a working gas... 

Access to potable water with standard quality is an inevitable component of human’s lives. Seawater desalination is the precedure of removing the impurities and contaminants in water to achieve the suitable quality for human consumption. Freeze desalination, by consuming relatively much lower energy compared to other techniques has shown to be a promising method for desalination. This technique requires the exertion of a cold source to the system which is then accompanied by simultaneous rejection of the impurities from the water. Regarding this, a numerical study on freeze desalination a hollow cylinder is carried out to determine the effects of the design variables such as heat flux,... 

In this research, a multigeneration system was designed and evaluated, utilizing solar and geothermal energy to generate electricity, fresh water, hydrogen, and oxygen. The system's performance was assessed from energy, exergy, and economic perspectives. The setup involves a solar tower contributing energy to the gas cycle and a geothermal well supplying preheated water for the steam cycle. The system employs a molten salt cycle to capture heat from the solar receiver, transferring it to the air cycle. The remaining energy requirement is met by the Air Brayton cycle, which combines methane and hydrogen as fuels within the combustion chamber. Additionally, a steam cycle is integrated to...