Lastly, the pressure of the mix is increased with a pump and flow back to the generator (where thermal energy is provided in the first place). Refrigeration cycle (Figure 10): when thermal energy is provided at the generator, the refrigerant is evaporated out of the absorption medium. The gas then flows to the condenser, where it releases usable heat as it changes from the gaseous phase to the liquid one. The liquid refrigerant’s pressure is then lowered inside an expansion device as it moves to the evaporator. At this point (P0/T0), heat is added to the refrigerant and it evaporates back to the gas phase.
CHAPTER 1 1.1 Chemical reactions with descriptions of starting raw materials Ethylbenzene will undergo catalytic dehydrogenation to produce styrene. The dehydrogenation reaction of ethylbenzene is an endothermic and reversible reaction. The optimum temperature for the reaction to occur is 590℃ to 650℃ and pressure of 200 mmHg or slightly above atmospheric pressure (Meyers, 2004). The required catalyst is potassium-promoted iron oxide in the presence of steam. The dehydrogenation process can be represented by the following chemical reaction: The main by-products produced from the dehydrogenation of ethylbenzene are benzene and toluene, which can be represented by the following chemical equations: The starting raw materials for
1.3Thermodynamic analysis of Rankine cycle The heat source enters the system through the evaporator where the working fluid is heated to saturation or to its super heating point. After high pressure vaporized steam expands in the turbine. The stream of the expanded fluid is passed directly through condenser where it condenses to ambient temperature and condenser pressure. After leaving condenser the working fluid enters the pump the pressure is raised and the fluid is returned to the evaporator. Below given figure1.3a shows Schematic diagram of Rankine cycle.
2. Change in pressure – working of a windmill. 3. Change in volume - a gas rushing against a piston, gasoline engine (sudden creation of hot gases push the piston out). Heat energy specifically plays more roles in the field of thermodynamics.
The term “hydrothermal/solvothermal process” is defined as performing chemical reactions in solvents contained in sealed vessels in which the temperature of solvents can be brought to around their critical points via heating concurrently with autogenous pressures. The process is referred to as “hydrothermal” when water is used as the solvent. In some cases, this term is also used to describe processes conducted at ambient conditions. The term “solvothermal process” is used when organics are used as
The sucked atmospheric air is compressed into the Compression Cylinder and then it is sent to the Power Cylinder. The system through which the compressed air is transferred to the Power Cylinder is known as Crossover Passage. The compressed air is then mixed with injected fuel and the combustion takes places in the Power
It is also used in the power cells. They must undergo redox reaction. The fuel cells has a big advantage of not charging as you keep on supplying the fuel in the as the oxidant. ADVANTAGES OF THE HYDROGEN OXYGEN FUEL CELLS: • They are more efficient than the conventional power stations • The hydrogen oxygen fuel produces a non toxic by product thatb is water • They are even used as a fuel for rockets • The costs of the maintains is low DISADVANTAGES OF THE HYDROGEN OXYGEN FUEL CELLS: • The cost of maintains is low but the initial cost is very
To obtain gasoline from petroleum fractional distillation is used where in the different type of hydrocarbons from petroleum, which has different boiling points is heat at different temperature. The different hydrocarbons then condense to liquid. The main ingredients of gasoline are heptane (C7H16) and isooctane (C8H18). The heptane and isooctane undergoes cracking and polymerization. In the process of cracking is when large hydrocarbons break down to smaller hydrocarbons while the process of polymerization is when small hydrocarbons bind together to form larger hydrocarbons.
It is the process of which the separation of a mixture of various components such as chemical compounds by using their boiling points by heating them to a temperature where they will be easily evaporated and forms different fractions. It also requires standard atmospheric pressure to be carried out in this operation. Principles The principle of this distillation process is based on the difference of boiling points between the mixtures of two substances which is being used for the distillation. As the substances have different boiling points. So, with the passage of heat different impurities show different boiling point and separated easily with the help of outlet pipe.
Induction cooker heats a vessel with induction heating, in place of infrared radiation from electrical wires or a gas flame as with a conventional cooker. In induction cooker electrical energy transfer by induction phenomena from a coil into a metal vessel. The coil is mounted underneath