Using Pinch Analysis to Optimize the Heat Exchanger Network of a Regenerative Rankine Cycle for an E...
Download
1 / 11

MANE 6980: Third Progress Report November 21, 2013 Stephanie Barnes - PowerPoint PPT Presentation


  • 240 Views
  • Uploaded on

Using Pinch Analysis to Optimize the Heat Exchanger Network of a Regenerative Rankine Cycle for an Existing Modern Nuclear Power Plant. MANE 6980: Third Progress Report November 21, 2013 Stephanie Barnes. Background. Millstone Unit III Power Plant Regenerative Rankine Cycle

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' MANE 6980: Third Progress Report November 21, 2013 Stephanie Barnes' - arlen


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Using Pinch Analysis to Optimize the Heat Exchanger Network of a Regenerative Rankine Cycle for an Existing Modern Nuclear Power Plant

MANE 6980: Third Progress Report

November 21, 2013

Stephanie Barnes


Background
Background of a Regenerative Rankine Cycle for an Existing Modern Nuclear Power Plant

  • Millstone Unit III Power Plant

    • Regenerative Rankine Cycle

    • Consists of a steam generator, high pressure turbine, three low pressure turbines, condensers, six feedwater heaters, feed pumps

    • Condensate is reheated using the heat exchanger network (feedwater heaters) to improve plant efficiency


Pinch analysis
Pinch Analysis of a Regenerative Rankine Cycle for an Existing Modern Nuclear Power Plant

  • Optimize a power plant by using the heat energy from the streams, instead of using external heating and cooling methods (heat exchanger, furnace, cooler, etc.), to increase the thermal efficiency of the plant and minimize energy costs


Problem statement
Problem Statement of a Regenerative Rankine Cycle for an Existing Modern Nuclear Power Plant

  • Analyze a Regenerative Rankine Cycle, based on the Millstone Unit III heat balance, using pinch analysis techniques.

  • Determine the pinch point and minimum hot and cold utilities.

  • Evaluate retrofit methods and recommend improvements to the heat exchanger network to improve plant efficiency.


Methodology
Methodology of a Regenerative Rankine Cycle for an Existing Modern Nuclear Power Plant

  • Data Extraction: Performed a simplified analysis using 7 streams (1 cold from the condenser to the steam generator and 6 hot streams (1 for each feedwater heater in the current design)).

  • Obtain the Heat Capacities, Problem Table, Composite Curves, and Heat Cascade


Results
Results of a Regenerative Rankine Cycle for an Existing Modern Nuclear Power Plant

  • Determined the pinch point and hot and cold utility requirements for the Millstone Unit III heat exchanger network (HEN), using the problem table and heat cascade (shown).

  • The minimum hot and cold utility requirements are 1,641 MBtu/hr and 370,852 MBtu/hr, respectively, as determined by the software and 1,642 MBtu/hr and 371,225 MBtu/hr as determined by hand calculations.


Results cont
Results - Cont. of a Regenerative Rankine Cycle for an Existing Modern Nuclear Power Plant

  • Shifted Hot and Cold Composite Curves

    • Curves touch at the pinch point

    • External Utilities determined by the gaps between hot and cold curves at the endpoints


Results cont1
Results - Cont. of a Regenerative Rankine Cycle for an Existing Modern Nuclear Power Plant

  • Grand Composite Curve

    • Combined Hot and Cold Composite Curves

    • Can determine the minimum external utilities (x-axis) and the associated temperatures at the endpoints of the curve.

    • Pinch temperature is the point where net heat flow is equal to zero.


Results cont2
Results - Cont. of a Regenerative Rankine Cycle for an Existing Modern Nuclear Power Plant

  • Determined the optimal minimum temperature difference between the hot and cold streams is 50 F based on external utility requirements.


Results cont3
Results - Cont. of a Regenerative Rankine Cycle for an Existing Modern Nuclear Power Plant

  • Evaluated 10 additional cases to determine the effect of the number of heat exchangers and the supply and target temperatures on the external utilities.

  • Case11 provided the most significant decrease in the cold utility requirement.

    • Deleting the 5th and 6th point heaters decreased the cold utility requirement from 370,852 MBtu/hr to 37,228 MBtu/hr, as determined by the software, while keeping the hot utility at 1,641 MBtu/hr.

    • To provide adequate cost savings, it is recommended that the 5th and 6th point heaters be deleted and the exhaust from the turbines that enters the 5th and 6th point heaters be directed elsewhere, such as the main condenser.


Project schedule
Project Schedule of a Regenerative Rankine Cycle for an Existing Modern Nuclear Power Plant

  • Continue to work on the report and analysis based on advisor’s comments.


ad