Humidity Measurement Benefits in Power Plant Applications Jeff Bossong, H2O jeff.bossong@h2oop.com 847-991-7488

Objective of Presentation H2O Technology Power Plant Applications “Fits” for The Sensor Questions / Discussion

H2O Technology Absolute Humidity Sensor Advantages Direct measurement of the water molecule Dipole moment measuring effect In-situ measurement Advantages High temperature operation – 1000 F High particulate operation Minimal maintenance Corrosive and condensing environments are not an issue Accurate Robust (sensor life is 10 years minimum)

Installation Requirements Probe sizes – 490 mm or 1,470 mm lengths Flange - 4 inch, 150 lb. ANSI Power – 110V, 5 Amps Output Signal – 4..20 mA isolated Measurement unit – g/m3 corrected to 0C at process pressure Other Units – Equations are provided (i.e., dew point, RH, humidity ratio)

Picture / Drawing

Installation

Power Plant Applications Coal / Biomass Fired Boilers Tube leak detection Soot blower feedback Heat rate calculations Air heater in-leakage Dry scrubber control Environmental reporting Wet scrubber stack protection Optimization software input Pulverizer control Combined Cycle Tube leak detection Dew point measurement Feed water temperature control Environmental reporting Power augmentation Optimization software input

Combined Cycle Tube Leak Detection – HRSG Outlet Evaporative Cooler Simulation Assumed 98% RH when “On” Calculated to actual 1 lb/s to 4 lb/s difference 10 to 14 minute lag time

Evap Cooler “On/Off” EVAPORATIVE COOLER STATUS Inlet Humidity lb/s Combustion Humidity (lb/s) Total Calc (lbs/s) H2O Sensor ( lbs/s) Stack Moisture (% Volume) 7/25/2016 23:02 OFF 16.09701116 56.56725665 72.66426781 75.60185935 8.696037606 7/25/2016 23:00 ON 19.79422018 56.57300391 76.3672241 75.505658 8.673321724 7/25/2016 22:58 19.74922556 56.5458247 76.29505026 75.4045441 7/25/2016 22:56 19.74773989 56.47017469 76.21791458 75.21135019 8.64761744 7/25/2016 22:54 19.861881 56.44564675 76.30752776 76.19288218 8.746051519 7/25/2016 22:52 20.1454894 56.9898044 77.1352938 77.0041557 8.750278445 7/25/2016 22:50 20.31508246 57.60453434 77.9196168 78.40180528 8.876212359 7/25/2016 8:36 19.90844146 57.14710304 77.05554449 73.00559558 8.268589916 7/25/2016 8:34 13.74889695 56.67495036 70.42384732 72.86760738 8.296438714 7/25/2016 8:32 13.59854159 56.1371447 69.73568629 72.49206208 8.318044784 7/25/2016 8:30 13.2374602 55.49160064 68.72906085 70.57454411 8.260980826 7/25/2016 8:28 12.98912114 55.01802972 68.00715086 70.12765084 8.270824445 7/25/2016 8:26 12.58297646 53.91791815 66.50089461 68.45955383 8.250144958 7/25/2016 8:24 12.58414433 54.02888045 66.61302477 68.47226655 7/24/2016 22:26 9.033737364 60.7101261 69.74386346 73.68303807 7.974083418 7/24/2016 22:24 15.36772811 60.66298523 76.03071334 73.30992106 7.930906723 7/24/2016 22:22 15.36238971 60.64591595 76.00830567 73.87137673 7.989711452 7/24/2016 22:20 15.36620911 60.74015603 76.10636514 73.56972356 7.952607264 7/24/2016 22:18 15.36719174 60.70547645 76.07266818 73.80420552 7.981445542 7/24/2016 22:16 15.37619736 60.75482703 76.13102439 75.06641323 8.124271345 7/24/2016 22:14 15.38841062 60.95134112 76.33975174 75.86518244 8.211780137 7/24/2016 10:44 22.13584472 60.33941426 82.47525898 79.39361312 8.843316078 7/24/2016 10:42 13.10766357 60.23421118 73.34187475 79.30337635 7/24/2016 10:40 12.64459249 60.44943521 73.09402771 80.32775216 8.961908867 7/24/2016 10:38 11.77540146 60.79848602 72.57388749 79.86597995 8.906824626 7/24/2016 10:36 15.042826 61.03517446 76.07800047 80.01096569 8.936928542 7/24/2016 10:34 13.55595462 60.83481418 74.39076879 79.21071919 8.822113724 7/24/2016 10:32 13.82604892 60.73932135 74.56537026 78.5210149 8.742658904 7/24/2016 10:30 14.4799356 60.42359013 74.90352572 78.24531834 8.724939131 7/24/2016 10:28 15.52952464 59.64946924 75.17899388 75.65197552 8.421780963 7/24/2016 10:26 12.40696425 57.37744456 69.7844088 73.76410303 8.282595168

Combined Cycle Dew Point Measurement – HRSG Outlet Water dew point equation Pd = (1-(0.0001*(SQRT((0.1*T)+1)+4)))*461.51*(T+273.15)*F*0.00001 Dp = (234.175*LN(Pd/6.1078))/(17.08085-LN(Pd/6.1078)) T = Temperature in C F = Absolute humidity at process conditions Pd = Water vapor pressure Dp = Dew point temperature Water dew point temperature varies 111 to 120 F Corrosion prevention during outages

CC Plant Water Dew Point

H2SO4 Determination Verhoff & Banchero Formula Tds = 1000/(2.276 - 0.0294 ln(p H2O) - 0.0858 ln(p SO3) + 0.0062 ln(p H2O) ln( p SO3)) Partial pressures are expressed as mmHg Use humidity sensor as a direct input to equation Use worst case constant for SO3 concentrations Varies six degrees as a function of H2O concentration

CC Plant Verhoff Chart – NG-CC

Sulfur Dew Point Data - CC SO3 PPM H2O % Tds (Celsius) Tds (Fahrenheit) 0.1 9 95.02302265 203.0414408 10 96.2719508 205.2895114 12 98.49671327 209.2940839 0.5 108.4980274 227.2964494 109.68744 229.4373921 111.8008703 233.2415665 1 114.6077618 238.2939712 115.7679809 240.3823657 117.8288282 244.0918907

Feed Water Temperature Control

Combined Cycle Environmental Reporting - Stack Provides real time, accurate moisture concentration EPA method 4 is not very accurate and data is a snapshot Could hurt or help depending on humidity number used for reporting Power Augmentation – Turbine Inlet Improved accuracy of dew point temperature Reduce factor of safety so inlet temperature can be lowered without condensation

Coal / Biomass Tube Leak Detection – Economizer Outlet Our detection limit is 0.1 g/m3 at 0C Volumetric flow rate: 372,000 m3/hr Detection limit = leak / volumetric flow rate Leak = .1*372,000 Leak = 37,200 g/hr Leak = 1.37 lbs/min or 0.17 gallons per minute Process noise includes ambient humidity, soot blows and fuel moisture More process noise but lower air flow In conjunction with laser based units

Coal / Biomass Economizer Outlet Soot blower feedback Safety to assure steam is firing Protect lances from bending and plant shutdown Heat rate calculations Fuel moisture variation Air heater efficiency Optimization software Input

Coal Biomass Air Heater In-Leakage Rate – Economizer Outlet and Air Heater Outlet Water doesn’t stratify like oxygen: more accurate, real time leakage rate Equation AHI * y + AHA * x = AHO * F , where F=x+y x = (AHI-AHO)*F/(AHI-AHA) AHI = H2O reading at air heater inlet AHA = ambient humidity in g/m3 (manual or real time) AHO = H2O reading at air heater outlet F = flow leaving air heater x = volumetric leakage rate y = flow entering air heater No flow measurement will still provide a relative difference

Verhoff Chart – Coal Plant

Sulfur Dew Point Data - Coal SO3 PPM H2O % Tds (Celsius) Tds (Fahrenheit) 1 9 114.6077618 238.2939712 10 115.7679809 240.3823657 12 117.8288282 244.0918907 5 129.5780044 265.240408 130.6603171 267.1885707 132.5811611 270.6460899 136.3876155 277.4977079 137.4314954 279.3766918 139.2834203 282.7101565

Coal Biomass Dry Scrubber Control – Scrubber Outlet, Baghouse Outlet or Stack Control to an approach to adiabatic saturation temperature Better SO2 removal at lower temperatures improves lime usage Protects baghouse from corrosion Moisture variables include soot blow, load change, fuel moisture, ambient air humidity and tube leaks Dew point can vary up to 10 degrees depending upon time of year and conditions GE Installations – Flint Creek and Braynton Point

Coal / Biomass Environmental Reporting – Stack Improved accuracy of emissions Wet scrubber stack protection Control reheat or bi-pass after scrubber Water carry over can increase moisture concentration past scrubber outlet dew point

Coal / Biomass Pulverizer Control – Pulverizer Outlet Sensor is a real time input for mass and energy balance across the pulverizer Sensor will also identify upset conditions like mill fires Tests were done at GE Windsor

“Fits” for Sensor Operations Optimization Asset Performance Management Thermal Performance Outage Planning Emissions Management & Reporting Asset Performance Management Tube Leak Detection Evaporative Cooling Upsets

“Fits” for Sensor Coal Optimization Software (Neuco, Etapro…) Thermal Performance Tube Leak Detection with Laser Systems Air Heater Leakage Dry Scrubber Control Emissions Management & Reporting Pulverizer Optimization

Questions / Discussion