Multipurpose Water Reuse in the Power Sector

Transcription

1 Multipurpose Water Reuse in the Power Sector August 10, 2017 WateReuse Webcast Series 2017 by the WateReuse Association

2 A Few Notes Before We Start Today s webcast will be 75 minutes. There are 1.25 Professional Development Hours (PDHs) available for this webcast. A PDF of today s presentation can be downloaded when you complete the survey at the conclusion of this webcast. If you have questions for the presenters please send a message by typing it into the chat box located on the panel on the left side of your screen. 2

3 Today s Presenters Joseph G. Jacangelo Stantec Mohammad Badruzzaman Stantec Carla Cherchi Stantec Robert Lotts Palo Verde 3

4 Mohammad Badruzzaman Stantec

5 Agenda Background Project Objectives Research Approach Water Quality Issues and Treatment Technologies Evaluation of Innovative Treatment Technologies A Success Story: Palo Verde Nuclear Generation Facility Critical Issues for Successful Implementation Summary Research Needs 5

6 Acknowledgements Funding Agency Water Environment & Reuse Foundation Florida Power and Light Project Team Members Maureen Keesano, Stantec Becky Hachenburg, Stantec Hal Schmidt, Stantec Kellogg Schwab, Johns Hopkins University Paul Jacobs, FPL Project Manager Kristan VandenHeuvel, WE&RF Project Advisory Committee Vijay Sundaram, Stantec Erin Westberg, Florida Power and Light Don Zylstra, West Basin Municipal Water District Other Contributors Richard Dennis, DeNora Jorg Menningmann, BiWater Naomi Jones, H2O Innovation Dow Chemical Toray 6

7 Thermoelectric Power Plant Operation is Water Intensive Thermoelectric power plants require a large quantity of freshwater to sustain operations Water requirement is dependent on the type of plant, fuel, choice of cooling system, and generation technologies Electric utilities are challenged by competitive use of water in water scarce regions, thus need to rely on alternative water sources Data Source: Meldrum et al. (2013) 7

8 Multipurpose Water Use at Electric Utilities Cooling make-up Boiler feed Environmental control Sanitation Irrigation of landscape Environmental stewardship Source: 8

9 Municipal Reclaimed Water as an Alternative Water Supply Degraded or non-traditional water supplies are being considered by the power sector to offset water consumption Reclaimed water is an alternative water sources considered due to the geographic accessibility Only sixty of five thousand power plants are currently using municipal reclaimed water in sixteen states* *Source: Cooper,

10 Collaboration Between Wastewater and Electric Utilities Source: Li et al.,

11 Opportunity for Collaboration Between FPL and MDWASD FPL was pursuing the licenses to build a new nuclear facility (1,100 MW) at its Turkey Point plant MDWASD obtained a new water use permit from SFWMD with conditions for reclaiming water currently injected in deep wells If the project moves forward, FPL might use 90 MGD of reclaimed water form MDWASD MDWASD WWTP FPL Proposed Plant 11

12 Project Objectives To review and summarize the treatment technologies currently being used to treat reclaimed water for cooling tower, boiler, and wetland rehydration applications To evaluate the effectiveness of selected traditional and innovative treatment technologies for the removal of nutrients and targeted contaminants for cooling tower, boiler and wetland rehydration applications To understand the benefits and challenges with the application of municipal reclaimed water at electric utilities 12

13 Research Approach Task 1: Literature Review Task 2: Case Studies Task 3: Bench-Scale Evaluation of Treatment Technologies Task 4: Conceptual Cost Analysis Task 5: Report Preparation and Project Management 13

14 Agenda Background Project Objectives Research Approach Water Quality Issues and Treatment Technologies Evaluation of Innovative Treatment Technologies A Success Story: Palo Verde Nuclear Generation Facility Critical Issues for Successful Implementation Summary Research Needs 14

15 Water Quality Goals Constituents that are regulated due to environmental concerns (VOCs, heavy metals) Constituents that impact operational performance o Mineral scaling and biological fouling o Corrosion of heat transfers and structural metals o Fouling loads on cooling tower fill (i.e., settleable solids) Feed water requirements for boilers vary widely depending on boiler design characteristics (e.g., pressure, heat transfer rate, etc.) 15

16 Nutrients Removal is Critical if Reclaimed Water is Used Cooling Towers Excess nutrients (N) cause undesirable biological growth, which: Plug of heat exchangers Film formation on cooling tower media Plug of water distribution nozzles/sprays Wetland Rehydration Excess nutrients (N and P) cause undesirable: Ecological risks for aquatic organisms Anoxia of water bodies 16

17 Nutrient Management Can be Done at the Wastewater Plant or at the Electric Utility Wastewater Treatment Plant Power Plant Scenario 1: Nutrient removal is performed at WWTP Scenario 2: Partial nutrient removal is performed at WWTP On-site breakpoint chlorination On-site treatment plant 17

18 Case Study: West Basin Municipal Water District, CA Edward C. Little Water Recycling Facility (ECLWRF) located in El Segundo (CA) treats secondary effluent from Hyperion Treatment Plant (HTP) Treated water is supplied to nearby oil refineries for cooling tower and boiler applications 18

19 Case Study: West Basin Municipal Water District, CA Ammonia is a concern because the refinery operates the cooling towers at cycles of concentration with shell tube heat exchanger Biofor (Degremont) was designed based on 8 mg-n/l of feed ammonia for 90% removal, with no recycle Increased influent ammonia levels is dealt with breakpoint chlorination; but, breakpoint chlorination, in turn, increased the levels of TDS and chlorides in the effluent 19

20 Water Quality Drivers for this Study MDWASD s Reclaimed Water Quality Parameter Average Concentration Alkalinity, mg/l CaCO TOC, mg/l 12.5 COD, mg/l 29.7 PO 4 -P, mg/l 1.8 Cl, mg/l 99.7 SO 4, mg/l 30.6 TP, mg/l 2.0 TN, mg/l 25.3 NH 3 -N, mg/l 19.9 Water Quality Requirements for FPL Cooling Towers and Wetlands Water Quality Targets Parameter Cooling Towers Wetland Rehydration Ammonia, mg-n/l <1 - Nitrate, mg-n/l <10 - TN, mg-n/l Ortho-P, mg-p/l 1 - TP, mg-p/l TSS, mg/l Boiler Feed Parameter Boiler Make-up Requirements Sodium, mg/l Sulfate, mg/l Chloride, mg/l Silica, mg/l 0.01 TOC, mg/l

21 A Biocatalyst Based Treatment Technology was Used A solid structure of hydrated hydrophilic polymer with internal porous structure (5-100 µm) A population of non-growing, metabolically active microorganisms, irreversible retained in the interior structure Concentrations >10X of conventional activated sludge systems 21

22 Biocatalysts Used in this Study Aerovi TM Denitrovi TM MB-POWR TM 22

23 Conceptual Treatment Trains for Cooling Tower and Wetland Rehydration Water Quality Targets Parameter Cooling Towers Wetland Rehydration Ammonia, mg-n/l <1 - Nitrate, mg-n/l <10 - TN, mg-n/l Ortho-P, mg-p/l 1 - TP, mg-p/l TSS, mg/l 3 23

24 Conceptual Treatment Trains for Boiler Feed Parameter Boiler Make-up Requirements Sodium, mg/l Sulfate, mg/l Chloride, mg/l Silica, mg/l 0.01 TOC, mg/l

25 Carla Cherchi Stantec

26 Agenda Background Project Objectives Research Approach Water Quality Issues and Treatment Technologies Evaluation of Innovative Treatment Technologies A Success Story: Palo Verde Nuclear Generation Facility Critical Issues for Successful Implementation Summary Research Needs 26

27 Bench-Scale Set-up for Biocatalyst Experiments Parameter Aerovi Denitrovi MB- POWR Mode of operation CSTR CSTR CSTR Reactor type Aerobic Anoxic Aerobic Sparging matrix Air - Air Sparging location In reactor - In reactor Mixing energy, W 6.5 x x x10 3 Reactor volume, ml Biocatalyst volume, ml Design packing density (%) Empty Bed HRT, h 6, 4, 2 2, 1.5, 1 6, 4 27

28 Ammonia Removal Performance of Aerovi Biocatalyst Ammonia Concentration (mg-n/l) HRT ( acclimation) 6 HRT 4 HRT 2 HRT NH3-N (Influent ) NH3-N (Effluent) Days >99% ammonia removal efficiency at 6 and 4 h HRT meeting the requirements of <1 mg-n/l 28

29 Nitrate Removal Performance of Denitrovi Biocatalyst EBHRT COD:N 2 h 1 h 1.5 h Concentration, mg-n/l NO2-N (influent) NO3-N (influent) NO2-N (effluent) NO3-N (effluent) 95-99% nitrate removal efficiency achieved meeting the requirements of <10 mg-n/l ,000 1,200 1,400 Hours 29

30 Total Nitrogen Removal Performance of Denitrovi Biocatalyst 30 TN (influent) TN Concentration (mg-n/l) TN (effluent) 95-99% nitrate removal efficiency achieved above 1.5 HRT meeting the requirements of 0.27 mg-n/l Hours 30

31 P removal Performance of MB-POWR Biocatalyst EBHRT COD/P Concentration (mg-p/l) h 4 h PO4-P (influent) PO4-P (effluent) TP (influent) TP (Effluent) Day 31

32 P removal Performance of MB-POWR Biocatalyst 2.5 PO4-P (influent) PO4-P (effluent) TP (influent) TP (Effluent) Concentration (mg-p/l) Days 32

33 Chemical Precipitation for Phosphorus Removal Chemical precipitation was tested as proof-of concept study under non optimized conditions Achieving LOD that met mg-p/l was a challenge Total P (mg-p/l) Total P (mg-p/l) Blank (Al) 10 mg-al/l 15 mg-al/l 15 mg-al/l (ph 7.5) Al Dose 20 mg-al/l Blank (Fe) 15 mg-fe/l 20 mg-fe/l 20 mg-fe/l (ph 6.93) Fe Dose 25 mg-fe/l 33

34 Adsorption for Phosphorus Removal Adsorption was tested with RSSCT as proof-of concept study under non optimized conditions Achieving LOD that met mg-p/l was a challenge 3 TP (mg-p/l) Column A Column B Bayoxide E33 Weight (g) Bayoxide E33 Depth (cm) Flow Rate (ml/min) Column A Column B Bed Volumes 34

35 Reverse Osmosis for TDS Reduction Testing conducted using a Sepa Membrane Cell (Osmonics) on two membranes: o DOW BW-30 o Toray TM700 Parameter Feed Water Boiler Make-up Requirements DOW BW-30 1st Pass 2nd Pass Toray TM700 1st Pass 2nd Pass Chloride (mg/l) ND Total Sodium (mg/l) ND Specific Conductance (µmho/cm) NA NA Sulfate (mg/l) ND ND TDS (mg/l) ND ND TOC (mg/l) ND ND ND NA Silica (mg/l) ND ND ND ND Note: MRL higher than the boiler make up requirements (except for TOC) NA: Not available ND: Below detection limit 35

36 Conceptual Cost Analysis Class 5 capital, operation and maintenance cost estimates were developed for screening process alternatives The expected accuracy range for the cost estimates is -20% to 50% (low) and +30% to +100% (high) Cost developed based on the outcomes of the bench-scale study Water Reuse Application Scenario #1 (MGD) Scenario #2 (MGD) Cooling Towers Boilers 1 1 Wetland Rehydration Technologies tested individually Limited process characteristics and chemical use optimization Blending opportunities for different flows and water reuse options not considered 36

37 Conceptual Cost Analysis of Treatment Technologies Water Production Cost ($/1000 gal) $4.00 $3.50 $3.00 $2.50 $2.00 $1.50 $1.00 $0.50 $0.00 Total Operating Cost Amortized Capital Costs Cooling Towers (with chemical precipitation) Cooling Towers (with adsorption) Scenario #1 Water Production Cost Wetland Rehydration (with chemical precipitation) Wetland Rehydration (with adsorption) Boilers 37

38 Conceptual Cost Analysis of Treatment Technologies Total Water Production Cost ($/1000 gal) Scenario #1 Scenario #2 Cooling Towers (with chemical precipitation) Water Production Cost Cooling Towers (with adsorption) Wetland Rehydration (with chemical precipitation) Wetland Rehydration (with adsorption) Boilers 38

39 Robert Lotts Palo Verde

40 Redhawk Power Plant (APS) 1,000 MW CC Mesquite Power Plant (SRP & Sempra) 1,000 MW CC 220 Acre Evap Pond #2 Capacity 5,009 AF 85 Acre Reservoir Capacity 2,300 AF 45 Acre Reservoir Capacity 1,075 AF Essential Spray Ponds 250 Acre Evap Pond #1 Capacity 5,218 AF 180 Acre Evap Pond #3 Capacity 6,542 AF Cooling Towers 40

41 Palo Verde By the Numbers Concept presented to APS Board of Directors in 1969 Arizona Nuclear Resource Study Group completed study in 1971 Initial construction permit May 1976 Began commercial operation Unit 1: January 1986 Unit 2: September 1986 Unit 3: January

42 Palo Verde By the Numbers Largest power generator in the U.S. Total output 4,030 net megawatts Meets the electrical needs of approximately 4 million people around the clock 42

43 Palo Verde Participants Public Service Co. of New Mexico (10.2%) El Paso Electric (15.8%) So. California Public Power Authority (5.91%) Purchased from SRP Los Angeles Dept. of Water & Power (5.7%) Purchased from SRP APS (29.1%) So. California Edison Co. (15.8%) Purchased from Tucson Electric SRP (17.49%) 43

44 Palo Verde Nuclear Generating Station Water Reclamation Facility Because of its desert location, Palo Verde is the only nuclear power facility that uses 100% reclaimed water for cooling. Unlike other nuclear plants, Palo Verde maintains Zero Discharge, meaning no water is discharged to rivers, streams, or oceans. 44

45 Cooling Water Options Evaluated (Estimated need = 140,000 AFA, 46B gallons annually) Groundwater Sustainability Subsidence issues Surface Water Limited accessibility Supply fully appropriated Colorado River Water Accessibility issues (1973) Effluent Adequate supply Reliable and sustainable Not being utilized in Photo Source-Land Subsidence near Phoenix AZ, courtesy ADWR

46 Conveyance System 28.5 miles of gravity flow with 100-foot elevation drop, 8 miles pumped flow with 150-foot elevation increase Total volume ~67 Million Gallons Phoenix-area Water Treatment Plants 6 miles of 114 gravity flow pipe 8 miles of 66 pressure flow pipe 22.5 miles of 96 gravity flow pipe Hassayampa Pump Station 46

47 Water Reclamation Facility The Palo Verde Water Reclamation Facility (WRF) is a 90 MGD tertiary treatment plant that reclaims treated secondary effluent from local valley cities 47

48 Water Reclamation Facility Flow Path Sulfuric acid (reduce ph) and chlorine (control biological growth) 560,000 GPM 85-acre Reservoir Gravity Filters Suspended solids captured Clarifiers Phosphates, Magnesium, Silica and Calcium removed Trickling Filters Reduce ammonia and alkalinity 45-acre Reservoir Underground Pipeline Delivers effluent to Palo Verde 48

49 Water Use Average cooling water intensity 760 gallons/mwh Average cooling water make-up 73,000 acre feet Cooling water cycles Cooling tower blowdown 3,000 Acre Feet (>5%) 49

50 License Renewal

51 Palo Verde Economic Impact Total estimated annual impact of $1.8 billion in Arizona Largest single commercial taxpayer in Arizona, including nearly $50 million in property taxes annually Local purchases of materials and services Palo Verde employees donate approximately $1 million annually to local charities Approximately 2,500 employees ARIZONA PUBLIC SERVICE COMPANY (APS). ALL RIGHTS RESERVED. THE TRADEMARKS AND LOGOS OF APS MAY ONLY BE USED WITH APS WRITTEN CONSENT OR AS OTHERWISE ALLOWED BY LAW. SOURCE: Applied Economics, Palo Verde Economic Study, May 2010

52 Mohammad Badruzzaman Stantec

53 Agenda Background Project Objectives Research Approach Water Quality Issues and Treatment Technologies Evaluation of Innovative Treatment Technologies A Success Story: Palo Verde Nuclear Generation Facility Critical Issues for Successful Implementation Summary Research Needs 53

54 Critical Issues for Application of Reclaimed Water Contracts Infrastructure Regulations Planning Treatment Technology Project Elements Design and Construction Operation Maintenance On-site Storage Control and Monitoring WQ Fluctuation Biological Growth 54

55 Summary Innovative biocatalyst-based technologies show promise for nutrient removal from reclaimed water for cooling tower use in the power sector and for wetland rehydration purposes Adsorption and chemical precipitation processes have potential to achieve low levels of phosphorus in the treated water. However, phosphorus removal to meet ultralow requirements is still a challenge for FPL Reverse osmosis process train may require post-treatment to achieve reduction of TDS and ions from reclaimed water for reuse in boiler applications in the power sector Overall, municipal reclaimed water can be an attractive alternative to freshwater water supplies if consistent water quality and quantity can be ensured at a competitive price 55

56 Future Research Needs Long-term pilot studies of the treatment technologies including the ones included in this study are needed for further characterization of process performance, costs, and operational issues Further understanding of the business model (tangible and nontangible costs and benefits) and best practices for the use of reclaimed water at electric utilities is needed A nationwide assessment of the untapped potential for reclaimed water use in the power sector should be conducted, and a database should be developed 56

57 Questions? Joseph G. Jacangelo Stantec Mohammad Badruzzaman Stantec Carla Cherchi Stantec Robert Lotts Palo Verde 57

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