Chemical Engineering
Hossein Hosseini; Asef Zare
Abstract
Gas turbines are usually designed in such a way that the pressure of hot gases at the exit of the turbine and after the last moving blade is slightly lower than the atmospheric pressure. Therefore, in order to overcome the ambient pressure, a divergent duct is considered at the gas turbine outlet, and ...
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Gas turbines are usually designed in such a way that the pressure of hot gases at the exit of the turbine and after the last moving blade is slightly lower than the atmospheric pressure. Therefore, in order to overcome the ambient pressure, a divergent duct is considered at the gas turbine outlet, and in this way, the exhaust gases, which have a relatively high temperature, are sent to the surrounding atmosphere through the exhaust. The useful output power is transferred to the compressor and then to the generator. Today, the use of gas turbines in power plants and as a generator of electricity is very valuable. In addition, they are widely used in various industries such as space industries, marine platforms, petrochemical industries, etc. These turbines can be useful especially in parts of the electricity industry that require quick installation and commissioning, as well as in cases where the national electricity grid is lost. Speed in construction and installation, low investment cost and low maintenance cost, light weight and the possibility of using multiple fuels are among the advantages of gas turbines compared to other power plants. Current gas turbines are operated with fuels such as natural gas, diesel, low thermal value gases, methane, crude oil, oil. Regarding the disadvantages of these turbines, we can mention the low efficiency and the need for major repairs after fewer working hours and the changes in power and efficiency due to atmospheric changes.
Chemical Engineering
Frank Delborty
Abstract
Central receiver solar systems are capable of generating electricity at high capacities and are more efficient than other similar systems due to their high operating temperature. These types of power plants can be used to supply steam to thermal power plants and also to produce hydrogen. Because, like ...
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Central receiver solar systems are capable of generating electricity at high capacities and are more efficient than other similar systems due to their high operating temperature. These types of power plants can be used to supply steam to thermal power plants and also to produce hydrogen. Because, like other solar systems, only energy from solar radiation is used, there are no problems with greenhouse gas emissions or environmental pollution. These systems are one of the few solar electrical systems that can properly store solar energy and inject the stored energy into the grid when necessary, such as at night or in cloudy weather. The above advantage can be used to store energy and deliver electricity during peak network times. A 100-megawatt power plant with a capacity of 12 hours of energy storage requires only 4,000 square meters of barren land and can well supply the energy needed by 50,000 households. There are millions of square meters of barren land in the central deserts and in the southern, southwestern and northwestern regions of Iran, which can be used as a source for solar energy production compared to hydropower.
