You are part of a team of engineers designing a new sub-critical power station. The power station is to produce 650 MW a
Posted: Fri Apr 29, 2022 9:46 am
You are part of a team of engineers designing a new sub-critical
power station. The power station is to produce 650 MW at the
turbine shaft. The maximum steam temperature is limited by tube
materials currently available to 540 °C. The lead design engineer
has recommended a maximum pressure of 20 MPa at the boiler
feedwater pump outlet. You are responsible for designing/selecting
the boiler feedwater pump, as well as the economiser. Your
colleagues responsible for the boiler did preliminary calculations
suggesting that the gas temperature at the economiser inlet will be
approximately 450 °C, and its mass flow rate is expected to be 1
040 kg/s. The team responsible for the condenser is of the opinion
that they can maintain a condenser pressure of 20 kPa. Design
considerations: • The plant configuration you choose should burn
the least amount of fuel for the power generated. • The
(condensate) extraction pump should ensure that the feedwater
pump(s) do not cavitate. • Is redundancy required for the feedwater
pump(s)? • The economiser should raise the feedwater temperature to
(almost) saturation temperature. • What is the composition of the
flue gas, and is the properties of air a close enough approximation
for the properties of the gas? • The flue gas contains ash
particles causing significant tube erosion. Tour economiser lay-out
should take that into account. Detail design • Your cycle design
should observe the laws of thermodynamics. • Your detailed pump
design should clearly motivate why the type of impeller you intend
to use is appropriate for this application. • Clearly sate the
number of stages in series and/or parallel that your pump(s) has. •
Provide a graph to demonstrate how (if appropriate) you got from a
single stage to multiple stages in your pump design. • Show that
the pump will not cavitate. • Justify the number of tubes, tube
sizes and material, as well as the number of tube passes in your
economiser. Also state the tube pitch along and across the gas
flow, and whether you intend to use a staggered or in-line tube
arrangement.
power station. The power station is to produce 650 MW at the
turbine shaft. The maximum steam temperature is limited by tube
materials currently available to 540 °C. The lead design engineer
has recommended a maximum pressure of 20 MPa at the boiler
feedwater pump outlet. You are responsible for designing/selecting
the boiler feedwater pump, as well as the economiser. Your
colleagues responsible for the boiler did preliminary calculations
suggesting that the gas temperature at the economiser inlet will be
approximately 450 °C, and its mass flow rate is expected to be 1
040 kg/s. The team responsible for the condenser is of the opinion
that they can maintain a condenser pressure of 20 kPa. Design
considerations: • The plant configuration you choose should burn
the least amount of fuel for the power generated. • The
(condensate) extraction pump should ensure that the feedwater
pump(s) do not cavitate. • Is redundancy required for the feedwater
pump(s)? • The economiser should raise the feedwater temperature to
(almost) saturation temperature. • What is the composition of the
flue gas, and is the properties of air a close enough approximation
for the properties of the gas? • The flue gas contains ash
particles causing significant tube erosion. Tour economiser lay-out
should take that into account. Detail design • Your cycle design
should observe the laws of thermodynamics. • Your detailed pump
design should clearly motivate why the type of impeller you intend
to use is appropriate for this application. • Clearly sate the
number of stages in series and/or parallel that your pump(s) has. •
Provide a graph to demonstrate how (if appropriate) you got from a
single stage to multiple stages in your pump design. • Show that
the pump will not cavitate. • Justify the number of tubes, tube
sizes and material, as well as the number of tube passes in your
economiser. Also state the tube pitch along and across the gas
flow, and whether you intend to use a staggered or in-line tube
arrangement.