Sustainable Water Integrated Management - Support Mechanism (SWIM- SM) Project funded by the European Union REVISED Final Report ASSESSMENT OF BEST AVAILABLE TECHNOLOGIES FOR DESALINATION IN RURAL/LOCAL AREAS Version Document Title Author Review and Clearance 2 ASSESSMENT OF BEST AVAILABLE Dr Adil Hosny Khordagui, Stavros TECHNOLOGIES FOR DESALINATION IN Bushnak Damianidis and Vangelis RURAL/LOCAL AREAS Konstantianos Contents Executive Summary ............................................................................................................... 8 1. Introduction .................................................................................................................... 10 2. Survey of BAT for desalination with focus on rural areas and description of renewable energy technologies for desalination ................................................................................... 11 2.1 Description of available desalination technologies, their merits and weakness related to use in rural areas:...................................................................................................................... 11 2.1.1 Multi-Stage Flash (MSF) ............................................................................................................................11 2.1.2 Multi-Effect Distillation (MED) ..................................................................................................................13 2.1.3 Vapour Compression Distillation...............................................................................................................15 2.1.4 Reverse Osmosis .......................................................................................................................................16 2.1.5 Electro-dialysis ..........................................................................................................................................19 2.1.6 Electro-dialysis Metathesis (EDM) ............................................................................................................20 2.1.7 Membrane distillation (MD)......................................................................................................................21 2.1.8 Thermo-Ionic TM Desalination (Saltworks Technologies Inc.).....................................................................23 2.1.9 Forward Osmosis.......................................................................................................................................25 2.1.10 Solar Stills................................................................................................................................................27 2.1.11 Humidification/Dehumidification (HDH).................................................................................................27 2.2 Description of renewable energy technologies for desalination BATs............................... 32 2.2.1 Solar energy ..............................................................................................................................................32 2.2.2 Wind energy..............................................................................................................................................32 2.2.3 Geothermal ...............................................................................................................................................33 2.2.4 Waste Heat Availability.............................................................................................................................34 2.3 Process/RE resource combinations .................................................................................... 34 2.3.1 Solar thermal-MED....................................................................................................................................34 2.3.2 Solar thermal-HDH ....................................................................................................................................35 2.3.3 Solar thermal-MD......................................................................................................................................36 2.3.4 PV-RO ........................................................................................................................................................37 2.3.5 PV-ED.........................................................................................................................................................38 2.3.6 Wind-RO....................................................................................................................................................39 2.3.7 Wind-MVC.................................................................................................................................................39 2.3.8 Geothermal MED ......................................................................................................................................39 2.3.9 Geothermal HDH and other thermal processes........................................................................................39 Page- 2 Sustainable Water Integrated Management - Support Mechanism (SWIM- SM) Assessment of Best Available Technologies for Desalination in Rural/Local Areas 3. Decisions, data and information before considering technologies for implementation of a desalination project............................................................................................................. 40 3.1 Integrated Water Resource Management Plan or diagnostic study .................................. 40 3.2 Capacities of Desalination Plants........................................................................................ 40 3.2.1 Definitions.................................................................................................................................................40 3.2.2 Desalination Plant Capacity.......................................................................................................................41 3.3. Desalinated water quality.................................................................................................. 41 3.4 Demographic and socio-cultural considerations ................................................................ 42 3.5 Cultural, religious & gender related issues:........................................................................ 42 3.6 Raw water resource availability & quality .......................................................................... 43 3.7 Brine discharge location...................................................................................................... 43 3.8 Pricing structures & financing schemes (Affordability) ...................................................... 43 3.9 Institutional and regulatory factors.................................................................................... 44 3.9.1 Institutional Factors ..................................................................................................................................44 3.9.2 Regulatory Factors ....................................................................................................................................45 3.10 Desalination Project systems............................................................................................ 46 3.11 Selection of the site of the desalination plant.................................................................. 47 3.12 Budgeting and implementation costs including total cost of water ................................ 47 4. Guidelines to screen and assess BAT options for desalination with focus on rural areas.... 49 4.1 Evaluation of available water resources and demand characteristics ............................... 49 4.2 Evaluation of available renewable energy sources and grid connectivity ......................... 50 4.3 Short listing of candidate desalination processes based on available RES ........................ 51 4.4 Maturity and level of deployment of the processes .......................................................... 51 4.5 Pre-treatment requirements .............................................................................................. 52 4.6 Operational skill level required........................................................................................... 52 4.7 Energy storage vs Water storage options........................................................................... 53 4.8 Brine disposal...................................................................................................................... 54 4.8.1 Brine Disposal methods and comparison..................................................................................................54 4.8.2 General on Brine disposal .........................................................................................................................58 4.9. Other practical site characteristics .................................................................................... 59 4.10 Capital and operating costs of the total proposed solution (See also section 3.12)........ 59 Page- 3 Sustainable Water Integrated Management - Support Mechanism (SWIM- SM) Assessment of Best Available Technologies for Desalination in Rural/Local Areas 5. Modality for assessing community needs......................................................................... 59 5.1 Geographical considerations .............................................................................................