Heat Rejection Cycle Testing Kenneth Hennon CleanAir Engineering - PowerPoint PPT Presentation

Heat Rejection Cycle Testing Kenneth Hennon CleanAir Engineering Performance Group Clean Coal International Conference November 2013

Overview Heat Rejection Cycle Testing • Combining Tests • Water Flow Rate • Cost of Malperformance • Case Studies 2

Heat Rejection Cycle Testing • Cooling tower thermal performance testing • Condenser cleanliness testing • Pump performance through circulating water flow rate determination • Evaluation of the component impact on turbine back pressure

Why Test? ECONOMICS • Thermal efficiency – A 650 MW – 85 percent load factor – Fuel costs $50/ton • Saves $950,000 in the first year by improving heat rate by only one percent and reduces emissions. 4

Why Test? 2011 Test Results 50,000 gpm 57% of New Acceptance Tests >50,000 gpm Yielded Tower Capability of 100% or greater

Why Test? 2010 Test Results 160 Test Capability -- % Design Flow 150 50,000 gpm 140 130 120 110 100 90 80 70 22% of New Acceptance 60 50 Tests >50,000 gpm 40 Yielded Tower Capability 10 100 1,000 10,000 100,000 Water Flow Rate (l/s) of 100% or greater 6

Why Test? 2009 Test Results 160 Test Capability -- % Design Flow 150 140 50,000 gpm 130 120 110 100 90 80 70 60 38% of New Acceptance 50 Tests >50,000 gpm 40 Yielded Tower Capability 10 100 1,000 10,000 100,000 Water Flow Rate (l/s) of 100% or greater

Why Test? 2008 COOLING TOWER THERMAL TESTS ACCEPTANCE TESTS -- NEW COOLING TOWERS 160 150 Test Capability -- % Design Flow 140 2,000 l/s (32,000 gpm) 130 120 110 100 90 80 70 60 6 out of 13 passed (46%) 50 40 10 100 1,000 10,000 100,000 Water Flow Rate (l/s)

Component Performance and CO 2 Change in HR Annual HR Increase in CO 2 Change in Component Performance (BTU/kWh) Cost (TPY) 10% Condenser Cleanliness 30 $330,000 17,000 10% Cooling Tower Capability 15 $165,000 8,500 10% Circulating Water Flow 20 $220,000 11,400

Component Performance and CO 2 Change in HR Annual HR Increase in CO 2 Change in Component Performance (BTU/kWh) Cost (TPY) 10% Condenser Cleanliness 30 $330,000 17,000 10% Cooling Tower Capability 15 $165,000 8,500 10% Circulating Water Flow 20 $220,000 11,400 10

Component Performance and CO 2 Change in HR Annual HR Increase in CO 2 Change in Component Performance (BTU/kWh) Cost (TPY) 10% Condenser Cleanliness 30 $330,000 17,000 10% Cooling Tower Capability 15 $165,000 8,500 10% Circulating Water Flow 20 $220,000 11,400 11

Component Performance and CO 2 Change in HR Annual HR Increase in CO 2 Change in Component Performance (BTU/kWh) Cost (TPY) 10% Condenser Cleanliness 30 $330,000 17,000 10% Cooling Tower Capability 15 $165,000 8,500 10% Circulating Water Flow 20 $220,000 11,400

Component Performance and CO 2 Cost in CO 2 Annual HR Total Annual Change in Component Performance Allowances Cost Cost 10% Condenser Cleanliness $57,000 $330,000 $387,000 10% Cooling Tower Capability $29,000 $165,000 $194,000 10% Circulating Water Flow $39,000 $220,000 $259,000 13 Clean Air Engineering,

Major Test Parameters • Water Flow Rate • Hot Water Temperature Cooling Range • Cold Water Temperature Approach • Inlet Wet Bulb Temperature • Fan Motor Power

Water Flow Instrumentation • Unreinforced – risers • Reinforced – large pipes

Water Flow Rate Measurements • Dye dilution can be used where pitot tube access is limited • Good applications for once- through systems • Can be used for closed loop systems with large volumes

Alternative Flow Measurement Techniques Dye Dilution Ultrasonic ???

Cooling Tower Performance Curves 18

Cooling Tower Performance Curves • Water Flow Rate • Wet Bulb Temp • Hot Water Temp • Cold Water Temp • Fan Motor Power

Fan Blade Pitch • On a historical basis, over 30% of the tested cooling towers have fans that are drawing significantly less power than designed • The loss of airflow equates to a 5% loss in operating cooling tower capability • $82,500/yr in HR & 4,250 TPY CO 2

5/6 H H 1/2 H 1/6 H 21

• In flowing channel – matrix of temperature sensors are used 22

Hot Water Temp at cooling tower is Heat Rejection Cycle the condenser discharge temp Drift Water Steam Fan Cooling Tower Condenser Hot Water Cold Water Circulating Water Pump

Water Flow Rate – Key to heat rejection cycle 25

Water Flow Rate Measurements • Pitot Tube, manometer, accessories • Water flow rate can be measured in pipes up to 20ft in diameter

Condenser performance (cleanliness) has the greatest impact on heat rejection cycle. Relatively easy to address cleanliness issues – air infiltration. 27 Clean Air Engineering,

Case Study 1 AC Power – Colver, PA • 110 MW waste coal fired plant • Single Pressure Condenser • Four cell counterflow tower • Two circulating pumps Clean Air Engineering,

Case Study 1 Test Parameter Unit Design Test Water flow rate gpm 57,000 56,873 Hot water temperature F 101.0 80.0 Cold water temperature F 81.0 59.8 Wet bulb temperature F 72.0 36.2 Cooling range F 20.0 20.5 Fan power hp 192.4 246.7 Capability % 100 98 Cold water temperature deviation at design conditions °F 0.3

Case Study 1 Parameter Units Design Test 4.94x10 8 5.76x10 8 Heat duty Btu/hr Steam condensed lbm/hr 522,520 --- Condensing steam pressure InHg 2.3 1.48 Condensing steam temperature °F 105.85 91.3 Circulating water flow Gpm 57,000 56,873 Inlet water temperature °F 91.0 59.5 Outlet water temperature °F 101.0 80.0 Cleanliness 85% 67%

Case Study 1 AC Power – Colver, PA • Cooling tower performance – OK • Pump performance – OK • Condenser – significant issues • Other plant instrumentation issues

Case Study 1 Comparison of 67% to 85% Condenser Cleanliness Wet Bulb Temperature (F) 32 39.7 47.4 55.1 62.8 70.5 70 Change in Heat Rate (Btu/kWhr) 60 50 40 55 Btu/kWh increase in HR due to Condenser Cleanliness at 70.5 WB 30 20 10 0 54 59 64 69 74 79 Inlet Water Temperature (F)

Case Study 1 Predicted Pressure 3.5 Predicted Pressure (InHg) 3.0 2.5 2.0 1.5 .3 InHg backpressure increase due to Condenser Cleanliness 1.0 30 40 50 60 70 80 90 Wet Bulb Temperature (F) Current Cooling System Performance 100% Cooling Tower 85% Cleanliness 33

Case Study 2 Hope Creek NGS • 1220 MW nuclear • Natural draft CF tower • 15% uprate approved • Single pressure condenser • Four circulating water pumps

Case Study 2 Test 1 Test 2 Test Parameter Unit Design 11:20-12:20 12:20-13:20 Water Flow Rate gpm 552,000 571,736 571,736 Hot Water Temperature F 119.0 110.9 111.1 Cold Water Temp F 90.0 86.7 87.2 Wet Bulb Temperature F 76.0 61.8 62.2 Dry Bulb Temperature F 87.3 71.4 71.4 Barometric Pressure In Hg 29.92 29.86 29.86 Cooling Range F 29.0 24.2 23.9 Relative Humidity % 60 58 60 Wind Speed mph N/A 7.6 4.8 Capability % 100 76 75 Cold Water Temperature Deficit ° F 4.6 4.8 35

Case Study 2 Parameter Units Value Number of units 2 7726x10 6 Heat duty Btu/hr 7.926x10 6 Steam condensed lbm/hr Condensing steam pressure inHg 4.56 Condensing steam temperature °F 130.3 Circulating water flow gpm 552,000 Inlet water temperature °F 92.0 Outlet water temperature °F 120.0 Cleanliness 64%

Case Study 2 Hope Creek NGS • Cooling tower – significant issues • Condensers performance- OK • Circulating flow rate - OK 37

Case Study 2 Expected Condenser Pressure 5.00 Condenser Pressure (inHg) 4.50 4.00 3.50 3.00 .6 InHg backpressure increase at 75F WB 2.50 2.00 40 50 60 70 80 Wet Bulb Temperature (F) Current Cooling Tower Perf 100% Cooling Tower

Case Study 2 Predicted Power 1270 1260 Predicted Power (MW) 1250 1240 14 MW loss due to cooling tower at 75F WB 1230 About 3 MW loss due to condenser at 75F WB 1220 1210 1200 40 45 50 55 60 65 70 75 80 Wet Bulb Temperature (F) Current Cooling System Performance 100% Cooling Tower 70% Cleanliness 39

Planning for a Test Planning a performance test begins with defining its objectives: • The validation of contractual guarantees for a new or modified plant, • Diagnostic tests to identify or quantify problems • Establish a performance benchmark against which future performance can be contrasted

Heat Rejection Cycle Testing • Solid tool for effective allocation of O&M • Quantifying impact and payback – Some problems are easy\inexpensive to fix • Complements other plant test programs

Any Questions?

Thank You for Your Attention! Contact Information: Ken Hennon 865.938.7555 Khennon@cleanair.com 43