Oxygenation Applications

Transcription

1 Oxygenation Applications IWA Symposium on Lake and Reservoir Management Oxygenation of Lakes and Reservoirs Workshop August 3, 2015 Presented by: Mark H. Mobley, P.E.

2 What Do These Diffusers and Things Look Like in Real Life? Air Lift Aerators, Aeration Towers Saturation Chambers Bubble Plume Hypolimnetic Oxygenation Destratification / Mixing

3 Aeration Towers

4 Saturation Chambers

5 Bubble Plume Diffusers

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7 Line Diffuser: Line Diffusers are a free bubble hypolimnetic diffuser system designed to place oxygen in specific layers and areas of the reservoir to achieve optimized DO enhancement: Oxygen bubbles are spread over large areas to obtain high oxygen transfer efficiencies and minimize vertical mixing. Diffusers up to a mile long are utilized to spread oxygen input into the reservoir. Diffusers are located at specific elevations above the reservoir bottom. Oxygen outflow distribution along the length of the diffuser is controlled with engineered orifice sizes.

8 Bubble Plume Diffusers Hypolimnetic Oxygen Destratification / Mixing

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11 How Are These Systems Supplied With Oxygen? Liquid Oxygen Storage Facility (LOx) Pressure Swing Adsorption (PSA) Compressed Air

12 Liquid Oxygen Storage Facility

13 Liquid Oxygen Storage Facility

14 Pressure Swing Adsorption (PSA)

15 Compressed Air

16 Compressed Air Distribution Manifold

17 What Are These Systems Used For? Hydropower Reservoir Release Improvements Water Supply Fish Habitat

18 Placing Oxygen in Hydropower Reservoirs: Avoids DO sag downstream Utilizes driving force of hydrostatic pressure and bubble travel time to achieve high oxygen transfer efficiency Improves water quality in the reservoir (locally) Reduces anoxic products Satisfies biological oxygen demands

19 Hydropower Oxygenation Objectives: Increase dissolved oxygen content of reservoir releases Achieve water quality requirements for regulatory agencies and licenses

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21 Reservoir Oxygen Diffusers in Water Supply Reservoirs

22 Aeration and Oxygenation Objectives: Eliminate Anoxia Decrease chemical demand (Fe, Mn, PO 4 ) Minimize eutrophication Reduce / eliminate algae blooms Provide improved water quality withdrawal options for multi-level outlet systems Increase overall water treatment capacity

23 Reservoir Oxygen Diffusers for Fish Habitat

24 Aeration and Oxygenation Objectives for Fish Habitat: Place oxygen in desirable habitat temperature range Eliminate anoxia Maintain 5 mg/l or better

25 Warm-water: Shiners (yellow) Bass (green), Cold-water: Brook trout (brown) Rainbow trout (gray/red). In Twin Lakes there is no oxygen for trout in bottom waters. As a result, they are squeezed into a thin layer between warm surface water and anoxic bottom water.

26 Trout found via acoustic monitoring Potential trout habitat Water quality and trout distribution in North Twin Lake in August 2007

27 How are the Systems Designed to Meet Site Specific Requirements? Oxygen Delivery Capacity Oxygen Placement Bubble Plume Strength Diffuser Layout

28 Hydropower Diffuser DO Patterns

29 Tillery Diffusers Four diffusers 3,500 feet long 320 to 680 feet supply 54 to 66 feet deep The diffusers are positioned in the old riverbed along the east side of the forebay in front of the hydroturbines and numbered 1-4 from the shoreline out like the turbine units. In order to provide flexibility in the vertical placement of oxygen in the reservoir, the diffusers are installed at two elevations. 87 MW Capacity

30 Gulf Island Pond Oxygen Diffuser Layout 2010

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32 Elevation (m) Water Supply Plume Characteristics Idealized Plume Modeled Plume Distance (m) Spring Hollow Reservoir (2004)

33 August 1, 2005 / Day 2 of Oxygenation 20 SCFM 20 SCFM

34 September 15, 2005 / Day 45 of Oxygenation 20 SCFM 20 SCFM

35 Approximate Scale (ft) N Approximate Current W.S. Elevation Full Pool W.S. Elevation

36 Line Diffuser in a Compact Layout for Reduction of Methylated Mercury in a CA Water Supply Reservoir

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42 Elevation (ft) Plume Design to Place Oxygen in Fish Habitat Gantzer Water Resources Engineering, LLC Distance (ft)

43 What Do These Systems Cost? Installation Operation and Maintenance

44 Tennessee Valley Authority Reservoir Diffuser Installations Blue Ridge Cherokee (TV) TVA Oxygen Costs Approximate Annual Usage: 25,000 tons Approximate Annual Cost $3M Douglas (TV) Ft Loudoun Hiwassee (TV) Norris (AVT) Nottely (FA) Tims Ford (TV) Watts Bar

45 Richard B Russell Oxygen Diffuser System Operating Costs 2,300 to 6,000 tons per year $184,000 to $660,000 per year

46 Do They Work? Hydropower Water Supply Fish Habitat

47 Cherokee Reservoir TVA Cherokee Dam Oxygenation System (1992) installed for hydro release DO improvements Created summertime fish habitat near the dam Cherokee Reservoir Near Jefferson City, TN 30,300 acres 1,200,000 acre feet 120 feet maximum depth 150 tons per day oxygen delivery capacity Stocked with 98,000 striped bass and 73,000 hybrid striped bass per year

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50 Cherokee s No Fishing Zone This 1,200 acre, no fishing zone has been in effect since 2001 and runs from July 15 to September 15. Bank fishing is OK, but no boat fishing for any species is allowed within the zone. Slide Courtesy of Doug Petersen, Tennessee Wildlife Resources Agency

51 Richard B. Russell Oxygen Diffuser System

52 Richard B Russell Dam and Reservoir Between Elberton, GA and Calhoun Falls, SC Eight hydro turbines 600 MW total 60,000 cfs maximum turbine capacity 26,500 acres 1,026,000 acre feet 110 feet maximum depth

53 Elevation (feet) Richard B. Russell Reservoir Profiles 9/19/01 During Operation of the Line Diffuser System DO (mg/l) 060B B13 B4 112B 120

54 0 Richard B. Russell Lake Depth (m) Depth (m) Depth (m) July August September Distance from Dam (km) Dissolved Oxygen (mg/l) Figure 10. Spatial distribution of dissolved oxygen concentration (mg/l) in Richard B. Russell Lake during July through September, 2002.

55 Oxygen Injection Rate (tons/day) Dissolved Oxygen (mg/l) Oxygen Injection Rate (tons/day) Dissolved Oxygen (mg/l) /2/03 7/17/03 8/1/03 8/16/03 8/31/03 9/15/03 9/30/03 10/15/03 10/30/03 0

56 Shepaug Dam Lake Lillinonah was formed by the construction of the Shepaug Hydroelectric Project on the Housatonic River near Danbury, Connecticut in It has a drainage area of about 1,400 square miles, a length of about 12 miles and a total volume of 74,000 acre feet. One single fixed blade turbine runner with a maximum capacity rating of 43 MW.

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60 Depth (m) Lake Lillinonah Station /21/06 DO (mg/l) 7/21/06 Temp (oc) 8/3/06 DO (mg/l) 8/3/06 Temp (oc) 8/11/06 DO (mg/l) 8/11/06 Temp (oc) 8/17/06 DO (mg/l) 8/17/06 Temp (oc) 8/23/06 DO (mg/l) 8/23/06 Temp (oc) 8/30/06 DO (mg/l) 8/30/06 Temp (oc) -40 DO (mg/l) T(C)

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62 DO (mg/l) Shepaug Release DO without Oxygen 2008 with Oxygen 1 0 May June July August September October

63 Embalse de Pinilla Lozoya River, Madrid Spain, 1995

64 Embalse de Pinilla Reservoir 38 hm 3 Water Treatment Problems: Iron Manganese Major algae blooms Oxygenation System Temporary Liquid Oxygen Supply Two Diffuser Lines Line A 600m upstream of intake 540m long diffuser 55 to 240 kg/h capacity Line B 120m upstream of intake 130m long diffuser 13 to 60 kg/h capacity

65 Embalse de Pinilla

66 Embalse de Pinilla Results 1995 and 1996 Levels of Fe and Mn reduced Sodium chlorite treatment eliminated DO levels increased only slightly Summertime stratification not altered No mixing of sediments No major algae blooms Copper sulfate treatment unnecessary Ramón Peña Martinez, Control of Eutrophication in Reservoirs, Centro de Estudios Hidrograficos- CEDEX 1998

67 Upper San Leandro Reservoir East Bay Municipal Utility District 2001

68 6,000 Gallon Tank and Vaporizer at Upper San Leandro Reservoir East Bay Municipal Water District, Oakland California

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70 Results in the Reservoir: Increased DO levels Lower manganese levels Slightly higher ph Slightly increased temperature NH 4 -N reduced by 95% * NO 3 -N increased by 85% * TN-N increased by 5% * Phosphate decreased by 35% * Geosmin levels decreased * As compared to 2 previous years (Horne et. al, 2003)

71 Elevation (feet) 450 Upper San Leandro Dissolved Oxygen Profiles With and Without Oxygenation Upper Diffuser Elevation Profiles With Oxygenation Lower Diffuser Elevation Dam 7/11/00 Intake 7/19/00 Dam 7/3/02 Intake7/3/ Dissolved Oxygen (mg/l)

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73 Results at the Water Treatment Plant: Ozone dose decreased by 45% Hydrogen peroxide advance oxidation treatment was eliminated Chlorine use decreased by 18% Trihalomethane (THM) levels in the treated water were reduced by 50% TOC remained the same (as expected for the short term)

74 Cost Savings at the Water Treatment Plant: Ozone doses decrease $11 / million gallons cost savings Hydrogen peroxide elimination $12 / million gallons cost savings Chlorine use decrease $3 / million gallons cost savings Chemical cost savings are more than twice the cost of oxygen used ($340/day)

75 C. W. Bill Young Regional Reservoir Diffused Aeration and Destratification System Tampa Bay Water October 16, 2014 Lithia, FL Mark Mobley, P.E., Vice President, Mobley Engineering, Inc.

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80 Calaveras Reservoir San Francisco Public Utility Commission Milpitas, California 2005

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83 Approximate Scale (ft) N Approximate Current W.S. Elevation Full Pool W.S. Elevation

84 Depth from Surface (ft) 0 Calaveras Reservoir DO Increases with HOS System DO (mg/l) Sep 7-Sep 26-Sep 3-Oct 6-Oct 13-Oct 9-Nov Sep Avg Oct Avg Nov Avg 2005 Results at Calaveras Reservoir San Francisco Public Utility Commission

85 Adult O. mykiss collected at San Antonio Reservoir in August 2009 (no oxygenation) (Courtesy SFPUC) Adult O. mykiss collected at Calaveras Reservoir in August 2009 (oxygenated since 2005) (Courtesy SFPUC)

86 J Strom Thurmond Oxygen Diffuser System

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89 Elevation (ft) Elevation (ft) Elevation (ft) Each line after 24+ hours of operation. Line 1 Line 2 Line Gantzer Water Resources Engineering, LLC Gantzer Water Resources Engineering, LLC Distance (ft) Distance (ft) 230 Gantzer Water Resources Engineering, LLC Distance (ft)

90 Elevation (ft) Dissolved Oxygen (mg/l) June 28, Line 175 SCFM Line 100 SCFM Line 400 SCFM Distance from dam (miles) Early 2012 operation

91 Elevation (ft) Dissolved Oxygen (mg/l) August 20, Line 100 SCFM Line 200 SCFM Line 200 SCFM Distance from dam (miles)

92 Elevation (ft) Dissolved Oxygen (mg/l) September 5, Line 400 SCFM Line 400 SCFM Distance from dam (miles) Well placed oxygen plume

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95 Mark H. Mobley, P.E. Mobley Engineering, Inc. PO Box 600 Norris, TN 37828