Design Problem:
You are asked to do a preliminary design of a 750 megawatt steam power plant to provide electricity. Specifications for the system are as follows:
• Boiler system: coal fired plant
• Cooling water: a nearby river with flow rate of 20 million m3 of water per day, winter temperatures of water ~4 °C, summer temperatures of water ~19 °C (note that these indicated temperatures do not include the added heat from the power plant)
• Limits on river water temperature to control dissolved oxygen: not to exceed 30 °C
• Targeted thermal efficiency of plant: >40%
• Targeted boiler outlet steam pressure: 22.0 MPa
• Targeted boiler outlet steam temperature: 575 °C
• Targeted boiler water inlet pressure: >22.0 MPa or as required
• Targeted boiler water inlet temperature: 300 °C
• Turbine must have at least 4-stages
• Inter-stage turbine steam quality must be 1.0, or superheated vapor
• Exit from last turbine stage steam quality x ≈ 0.92
• Power cycle: Must have both regenerative and reheating systems within a Rankine cycle
Work Assignment:
This is a team assignment and we can have groups of 2 or 3 students working together. You may work with whomever you wish in the class on this project. Generate a five-page typed summary report (12 point font, 1.5 line spacing, with a 1 inch boarder for top, bottom and sides), not including illustrations and computational documentation. Focus on describing your design of the process, not just power plants in general. You can assume isentropic conditions for this power cycle, and you must show representative calculations for all process claims. For any non-specified information, you may use typical power plant operational parameters, but you must cite your sources for this information. Your report must include the following:
1. An overall power plant process equipment schematic diagram of your design with a list of your overall system assumptions. (15 points)
2. A description of the boiler and any reheat or regenerative systems employed in your design. (20 points)
a. The equipment needed in a process schematic illustration
b. A preliminary mass balance for the boiler combustion process, including the mass flow rate of fuel, mass flow rate of the combustion air, and the mass flow rate and temperature of exhaust gases (including their ideal theoretical chemical composition).
3. A thermodynamic computational analysis of your Rankine cycle. (25 points)
a. A cycle process T-s diagram
b. An energy and mass balance
c. A thermal analysis and mass flow description of any multi-stage turbine and reheating systems
4. A thermodynamic computational analysis of your condenser cooling system. (25 points)
a. A cooling system process schematic
b. A mass and energy balance of the cooling system with its interaction with the cooling river water and that the system does not exceed the river maximum river temperature allowed
5. An overall system thermal efficiency analysis showing that your proposed design meets the required thermal efficiency. If your design does not meet the targeted 40% efficiency then you should include a short explanation as to what you would do to improve your design to meet or exceed the 40% goal. (15 points)