DESALINATION and SAN DIEGO S ROLE IN ITS DEVELOPMENT SHERMAN MAY, PE

Transcription

1 DESALINATION and SAN DIEGO S ROLE IN ITS DEVELOPMENT SHERMAN MAY, PE 1

2 INTRODUCTION Why Desalination? Desalination Process Development Desalination Processes Review Seawater Desalination Concerns San Diego s Contributions Applications Summary 2

3 WHY DESALINATION? EXISTING SUPPLIES MET WATER (MWD) GROUND WATER SURFACE WATER NEW SUPPLIES BRACKISH WATER RECYCLE SEAWATER 3

4 INTRODUCTION TO WATER WATER-Essential and a Universal Solvent TOTAL DISSOLVED SOLIDS (tds) What s in the water WATER SOURCE CHARACTERISTICS Brackish Sea Water WATER QUALITY REQUIREMENTS Drinking/Industrial/Agricultural/Aquatic COST/VALUE 4

5 TERMINOLOGY and UNITS TDS (ppm) RECOVERY RATIO (%) PRODUCT/PERMEATE BRINE/REJECT MWD (Metropolitan Water District) UNITS Gallons (100 gallons/day/person) Cubic Meters (264 gallons) Acre Feet (326,000 gallons) 5

6 DESALINATION PROCESS DEVELOPMENT PRESIDENT KENNEDY- No water resources program is of greater long-range importance than our efforts to convert water from the world s greatest and cheapest natural resources our oceans into water fit for our homes and industry. Such a break-through would end bitter struggles between neighbors, states and nations (1961) OFFICE OF SALINE WATER Five Test Centers-One was in San Diego 6

7 DESALINATION PROCESSES MULTI-STAGE FLASH (MSF) MULTI-EFFECT DISTILLATION (MED) VAPOR COMPRESSION (VC) FREEZING ELECTRODIALYSIS (ED) REVERSE OSMOSIS (RO) DEVELOPING PROCESSES! 7

8 MULTI-STAGE FLASH (MSF) GOR-Gained Output Ratio 8

9 DESALINATION PLANT (SUPPLIES RIYADH) 9

10 MULTI-EFFECT (ME) 10

11 ME PLANTS 11

12 MECHANICAL VAPOR COMPRESSION (MVC) 12

13 MVC KESTERSON RESERVOIR 13

14 FREEZING PROCESS 14

15 ELECTRODIALYSIS (ED) 15

16 RO FUNDAMENTALS Osmotic Pressure Seawater has a TDS of 35,000 ppm and osmotic pressure of 350 psi Brackish Water is only a few thousand TDS so low osmotic pressure (i.e. 20 psi) 16

17 RO MEMBRANE DEVELOPMENT Loeb-Sourirajan Membrane UCLA 17

18 RO MODULE 18

19 RO SCHEMATIC RECOVERY RATIO (RR) 19

20 RO PLANT PUMP BAY RO MODULES 20

21 PROCESS COMPARISON S/W ENERGY REQUIREMENTS SEAWATER DESALINATION PROCESS MULTI- STAGE FLASH MULTI- EFFECT DISTILLATION MECHANICAL VAPOR COMPRESSION REVERSE OSMOSIS MSF MED MVC RO Electric Energy (kwhr/m3) Thermal Energy (kwhr/m3) none none Electic Equivalent of Thermal Energy (kwhr/m3) none none Total Equivalent Electrical Energy (kwhr/m3) (kwhr/kgal)

22 DESALINATION COMPARISON BRACKISH vs. SEAWATER % of FEED REMAINING (RECOVERY RATIO) CONCENTRATION FACTOR SEAWATER TDS ,333 70,000 87, ,000 OSMOTIC PR ,750 BRACKISH WATER TDS ,333 4,000 5,000 10,000 20,000 40, ,000 OSMOTIC PR ,000 22

23 SEAWATER DESALINATION WATER COST CONCERNS ELECTRICAL ENERGY USAGE ALTERNATIVES SUPPLIES (CONSERVATION) IMPINGEMENT/ENTRAINMENT BRINE DISPOSAL GROWTH INDUCEMENT 23

24 DESALINATION COST 24

25 ELECTRICAL ENERGY USAGE CALIFORNIA Water Accounts For 19% of Electric Usage MWD WATER FROM NORTHERN CALIFORNIA 10.4 kwh/kgal (2.75 kwh/m3) AFFORDABLE DESALINATION COLLABORATION (ADC) Demonstrate Energy Consumption of 10.4 to 11.3 kw-hr/kgal ( kwh/m3) PERTH, AUSTRALIA (38 mgd) 8.7 to 13.2 kwhr/kgal (2.3 to 3.5 kwh/m3) REUSE (ORANGE COUNTY GROUNDWATER REPLENISHMENT SYSTEM) Requires About 1/3 of That Required for Seawater Desalination (SD says 1/6) BRACKISH DESALTING Depends But Is Less Than Seawater Desalination 25

26 CONSERVATION SAN DIEGO S WATER SUPPLY 26

27 IMPINGEMENT/ENTRAINMENT ENTRAINMENT-occurs when marine organisms enter the desalination plant intake system and enter the treatment facilities. MOSTLY A CONCERN WITH OPEN INTAKES INTAKE ALTERNATIVES SUBSEA OTHER METHODS UNDEFINED REQUIREMENTS FOR RO 27

28 INTAKE ALTERNATIVES 28

29 SAN DIEGO S CONTRIBUTIONS POINT LOMA DESALINATION PLANT CLAIR ENGLE MSF PLANT-SOUTH BAY ROGA-Reverse Osmosis General Atomics SPIRAL WOUND MEMBRANE CONCEPT SEVERAL OTHER RO COMPANIES CARLSBAD DESALINATION PLANT PROSPECTS TO SHARE DESALINATION PLANT WITH MEXICO 29

30 LOCAL COMPANIES MEMBRANES Hydranautics ROGA (Koch Membranes) ENGINEERING SPI Malcolm Pirnie PBS&J SUPPORT King Lee Avista Myron L Home RO units 30

31 WORLDWIDE DESALINATION APPLICATIONS Australia-117 mgd near Melbourne (H) Singapore-84 mgd Tuaspring Israel-143 mgd Sarek (H) Saudi Arabia-271 mgd Ras Azzour India-20 mgd Reliance refinery Japan-13 mgd Fukuoka UAE-500 mgd Taweelah 31

32 USA and LOCAL EXAMPLES South Florida-33 brackish and two seawater desalination plants, additional 7 plants under construction. Total capacity 245 mgd California-20 brackish desalting plants, 19 located in southern California. Plant capacities range from 500,000 to 10 mgd Texas-44 municipal brackish water desalination facilities 72 mgd Desalination Plant at Yuma Oceanside-6.4 mgd operating since 1992 Water Factory 21 is 70 going to 100 mgd Proposed San Onofre S/W Desalination Plant (~100 mgd) Proposed SD recycle project Santa Barbara, Marin County, Santa Cruz, 32

33 CALIFORNIA S/W FACILITIES 33

34 S/W DESALINATION AT ROSARITO BEACH POWER PLANT 34

35 RED SEA-DEAD SEA PROJECT Jordan River water over allocated Dead sea is being lost Water is in short supply Canal and pipeline carries ocean water to Dead Sea Power and Desalted water is produced 35

36 SUMMARY California is not unique in the application of seawater desalination Water can have a value far in excess of its cost Desalination is a dependable water supply as demonstrated in many countries in the world S/W desalination will become an increasing important part of our water supply San Diego has played a key role in desalinating development There continues to be process improvements (can t stand still) 36

37 INTAKE ALTERNATIVES INTAKE TYPE RELATIVE COST RELATIVE PRETREATMENT SPACE REQUIREMENTS RELIABILITY Beach Wells Low High Variable based upon litho logy Constructed High Medium Unknown Seabed/infiltration Gallery Submerged Open Medium- Low High Intake Low Surface-Open Low Low High Intake Co-located Intake Low Low High 37