Desalination: A Global Perspective. Craig R. Bartels, PhD HYDRANAUTICS

Transcription

1 Desalination: A Global Perspective Craig R. Bartels, PhD HYDRANAUTICS 1

2 Desalination Growth: Installed Capacity, (cumulative) Desal(ng Technology Mul(ple Effect Dis(lla(on Mul(ple Stage Flash Reverse Osmosis Total Electric Energy Equiv. kwhr/m ,800,000 8x40 Spiral Elements Typical Life: 3-6 years 2

3 3 DESALINATION TECHNOLOGY

4 RO Membrane Separation Mechanism Pressure FEED FLOW H 2 O + Na HCO 3 SO 4 ++ Ca H 2 O H 2 O Cl ++ Mg H 2 O ++ Fe Concentrated Salts H 2 O H 2 O H 2 O H 2 O H 2 O H 2 O Membrane Permeate 4

5 Osmotic Pressure Semi Permeable Membrane P π1 π2 P = π 2 - π 1 = Δπ Applied pressure required to prevent the flow of water through a semipermeable membrane from a dilute solution to a concentrated solution. Osm Press ~ 0.011* salinity in mg/l

6 Reverse Osmosis Semi Permeable Membrane P π 1 π 2 P > (π 2 - π 1 ) Osmotic flow can be reversed by applying a pressure greater than the osmotic pressure difference between the two solutions 6

7 SWRO Pressure Requirement Recent Membrane Improvements 62 bar = 900 psi Bar 33% of pressure is used to permeate water through the membrane Only 25% of pressure is used to permeate water through the membrane 7

8 GLOBAL COMMERCIAL APPLICATION 8

9 Regional Size of Desalination Market 26.4 BGD 9 Water Desalina@on Using Renewable Energy Technology Brief Interna@onal Renewable Energy Agency, IRENA ENERGY TECHNOLOGY SYSTEMS ANALYSIS PROGRAMME, March 2012

10 Large-Scale Plant References Example of Major Global Desal Plants Seawater Desalination : Total 6,000,000 m3 /d and over Wastewater Reclamation : Total 1,000,000 m3 /d and over Spain Carboneras 126MLD 02 Cartagena 65MLD 03 Escombreras 64MLD 07 Barcelona 200MLD 09 Algeria Skikda 100MLD 08 Beni Saf 200MLD 08 Tlemcen 200MLD 09 Honaine 200MLD 09 China Yuhuan 11.5MLD 06 Yueqing 10MLD 07 Qingdao 10MLD 07 Tianjin 100MLD 09 Japan Okinawa 40MLD 97 Fukuoka 50MLD 05 Singapore Bedok 42MLD 02 Kranji 40MLD 02 Ulu Pandan 166MLD 06 USA Orange County 264MLD 06 USA Tampa 95MLD 06 Carlsbad 190 MLD 15 Chile Antofagasta 52MLD 03 Saudi Arabia Rabigh 192MLD UAE Fujairah 170MLD 03 Al Hamriya 90MLD 08 Oman Barka 125MLD 08 Sur 84 MLD 09 Chennai India 100MLD MLD 13 Israel Sorek 440MLD 13 MLD: Million Liter Per Day Australia Gold Coast 132MLD 09 Adelaide 300MLD 10 Melbourne 450MLD 10

11 6 Key Aspects Affecting Desalination CAPEX 5-15% OUTFALL INTAKE CAPEX 5-20% PRETREAT CAPEX 15-20% RO SYSTEM CAPEX 40-60% POWER PRODUCT WATER 11 Carlsbad, CA Desal Plant

12 Global Desal Trends/Considerations v Reliability v Seawater quality, redundancy, technology acceptance v Energy Consumption/Cost v Membranes, Co-location at Power Plant v Water Quality Targets v TDS, Chlorides, Boron, Bromide, TOC v Pretreatment v Media Filters, Ultrafiltration, Floatation (DAF), v Intake/Outfall v Permitting, Shared intake, Wells, Env impact 12

13 Water Cost Components of a SWRO Plant Electric Power: 33% Maintenance: 8% Chemicals: 4% Labor: 4% Membrane Replacement: 3% Equipment Amor@za@on: 48% 13

14 Reported Energy Use in SWRO Plants Plant SWRO Energy only kwh/m3 Facility Energy kwh/m3 Capacity m3/d Capacity MGD SWRO Energy only $/1K gal permeate ADC Pilot $0.42 Melbourne , $0.59 Perth , $0.65 Barcelona , $0.76 Mekorot , $0.99 Fujairah , $1.01 Ashkelon , $1.03 Gold Coast , Valdelen(sco , Las Palmas , Larnaca , Energy es(mated at $0.07 USD per kwh

15 Energy Efficiency: Gold Coast Plant Desalina(on plant: $557.5 mill Intake/ouball: $280.6 mill Distribu(on pipeline: $218.5 mill Total capital cost: $1.057 bill Total water cost: $1.09/m3 $4.12/kgal 35 MGD 133,000 m3/d < 250 mg/l TDS < 50 mg/l Cl < 0.1 mg/l Br < 1 mg/l B 15 Reference: GHD publication, Gary Crisp, & WDR

16 Energy Use in the Gold Coast Plant Specific energy consumption (kwh/m3) < 50,000 m3/day > 100,000 m3/day Plant production 2.9 kwh/m3 11 kwh/kgal (80% of energy) Transformers losses Chemicals dosing pumps Misc. services Residuals treatment Potable water pumps Intake pumps Pretreatment RO 16

17 133 MLD Gold Coast SWRO Energy Consumption Total plant specific energy consumption Pretreatment + RO specific energy consumption kwh / m Energy Reduced ~10% by Split Permeate Design

18 Mega Plant: Melbourne, AUS 18 Source: WDR, Vol 48, #40 15 October ,200 8 SWRO Elements 14,280 8 BWRO Elements SWRO: 800 psi (8.4 kwh/kgal) < 20 mg/l Cl < 0.5 mg/l B < 0.1 mg/l Br

19 Melbourne Plant Pressure Profiles Gold Coast SWRO Melbourne SWRO SWC5 Avg Fd Press 19

20 Seawater Pretreatment Options v Beach Well v Coagulation and Clarification v Dual Media Sand Filters v Dissolved Air Flotation v Ultra/Micro Filtration 20

21 Growth of Membrane Pretreatment (based on 96 plants listed in public) MF/UF Pretreatment in Seawater Desalination: Applications and Trends Authors: Robert P. Huehmer, IDA Proceedings, Dubai 2009

22 Kindasa IMS Plant System Layout Start-up Fall

23 Kindasa Ultra Filtration System Design Capacity 14.9 mgd (56,500 m³/d) UF Membrane HYDRA cap60 MWCO 100,000 Daltons Number of Racks 8 Design Flux 53 gfd 97 lmh Max. Flux 61 gfd 106 lmh Recovery 94% Mode Dead End Filtration No Coagulant Addition

24 * These are not actual feed pressure values, but feed to filtrate differential pressure values (driving pressure) Average Filtration Energy Consumption UF BW UF Filtr n DMF BW DMF Filtr n Feed Flow (Avg) (gpm) 4,400 1,244 4,893 2,244 Feed Pressure (psi) * * Pump Efficiency (%/100) Pump Power (kw) Hours of oper n (Hours/day) Motor Efficiency (%/100) Specific Power (kwh/kgal) Total Specific Power (kwh/kgal) * These are not actual feed pressure values, but feed to filtrate differential pressure values (driving pressure) 24

25 Average RO Energy Consumption Average RO Energy Consumption Energy Credit from Energy Recovery Device SWRO HPP SWRO BP SWRO ERT BWRO LPP Feed Flow (Avg) (gpm) 3,568 2,364 1,783 1,418 Feed Pressure (psi) Pump Efficiency (%/100) Pump Power (kw) Hours of oper n (Hours/day) Motor Efficiency (%/100) Specific Power (kwh/kgal) Total Specific Power (kwh/kgal)

26 Relative Contribution of Plant Energy Consumption 0.20% 0.01% 0.51% Specific Power 0.30% 24.84% 14.80% 73.96% SWRO HPP-ERT SWRO BP BWRO LPP UF Bflush UF Filtration DMF BW DMF Filtration 26

27 Sorek Desalination Plant: 16 in SWRO 410,000 m3/d 108 mgd < 16 mg/l Cl < 0.26 mg/l B Ver(cal Vessels 16 : 1700 i2 8 : 400 i2 27

28 Sorek Compact Plant Design 1400 press vessels versus 5950 for 8 elements Water Selling Price: ~US$0.50 per m 3 ~US$1.89 per kgal 28

29 Conclusions v RO Desalination is most prevalent in Middle East and Mediterranean regions v RO Desalination plants are typically reaching mgd capacity v RO Desalination growth has been fueled by lower energy costs, high reliability, and greater experience v Energy costs range from $0.60 to $1.00 per kgal v Significant growth of membrane pretreatment v Cost reduction through new concepts such as improved membranes, co-location, and large elements. 29

30 More technical information can be found at: 30