Novel coupling of NPP with MED-RO Hybrid

Transcription

1 Novel coupling of NPP with MED-RO Hybrid Leon Awerbuch, Dean of IDA Desalination Academy, President International Desalination Consultancy Assoctiates LLC IAEA s Technical Meeting on User/Vendor Interface on Cogeneration for Electricity and Seawater Desalination using Nuclear Energy March 2016 Vienna, Austria 1

2 Water and Environment With dramatic interest in finding solutions to combat climate change in view of the impacts of global warming on water resources, Nuclear Desalination can offer significant potential to substitute fossil fuel as a source of energy for desalination. 2

3 The Global Clean Water Desalination Alliance H 2 0 minus CO 2 The Global Clean Water Desalination Alliance H 2 0 minus CO 2, initiated by Masdar in collaboration with France and the International Desalination Association, launches in Paris during COP21 With access to drinking water already a major challenge for as much as one quarter of the world s population, and further forecasts predicting that by 2030, 47% of the global population will face water scarcity, The Global Clean Water Desalination Alliance H 2 0 minus CO 2 is one of the few climate initiatives dealing with the waterenergy nexus and climate change. The Alliance s goal is to seek solutions that will substantially reduce the projected increase in CO 2 emissions from the desalination process, as global demand for drinking water continues to grow. We call on all to join the Alliance to bring the vision to reality

4 Global cumulative installed contracted and commissioned desalination capacity, Source: GWI DesalData / IDA,

5 How much desalinated water is produced worldwide? The IDA/GWI Inventory data show that there are 18,048 contracted plants with a total capacity of 92,060,618 m 3/ d of which 17,831 with a total capacity of 85,279,080m 3/ d have been commissioned. How many desalination plants are there around the world? There are over 18,000 desal plants, 5

6 The data project tremendous growth of desalination industry and Nuclear Desalination will play an important part in the future. 6

7 Energy Requirements for Desalination Process/energy type MED MED -TVC MSF RO Specific heat consumption, kj/kg, PR kg/2326 kj/kg Steam pressure, ata _ Electric energy equivalent, kwh/m * _ Electric consumption, kwh/m Total electric energy equivalent, kwh/m Courtesy of Leon Awebuch 7

8 Technology and Innovation The ability to provide both clean energy and water requires the use of innovative technologies, to meet the challenges of a clean environment, sustainability and affordability. The paper presents an approach to couple Nuclear Power Plant with Multi-Effect Distillation (MED) hybridized with Reverse Osmosis (RO) and Nanofiltration (NF). 8

9 Multi-Effect Distillation Technology (MED) MED Technology today uses relatively low temperature. Today MED plants design are limited to TBT only of 64 to 75º C. The MED specific power consumption is between kwh/ton of distillate depending on feed solution significantly lower than MSF requirements of typical 3,5-4 kwh/ton of product. Low-cost, high-efficiency form of solar water heating and trough CSP receiver, already in the development, to produce relatively low temperature heat source needed for desalination. 9

10 Multi-Effect Distillation Technology (MED) The size of MED units is growing rapidly. The largest MED plant in the world is currently the Jubail Water and Power plant (JWAP) a Marafiq plant built by SIDEM of France with 800,000 m3/d production capacity from 27 MED units of 6.6 MIGD per train. This is a dual purpose plant generating 2744 MW electricity in addition to desalinated water. The largest operational MED units are in Fujairah 2 with units of 8.5 MIGD capacity producing 455,000 m3/day (100 MIGD) also by SIDEM. This also the largest MED-RO Hybrid with 30MIGD A single unit of 15 MIGD was built for demonstration purposes in Yanbu by Doosan with capacity of 15 MIGD and a unit of 20 MIGD was offered by Sasakura of Japan and Sidem in KSA. 10

11 Marafiq IWPP - Saudi Arabia MED-TVC 800,000 m3/d, 27 units of 6.59 MIGD (178 million gallons daily production) Sidem.

12 MED 8x25,000 m3/day Units, PR Max 15, Tianjin, China Courtesy IDE 12

13 Az Zour North Phase 1 IWPP MW +107 MIGD MED Veolia/Sidem is completing Az Zour North Phase 1 IWPP MW +107 MIGD an EPC contract won in 2014 to build a desalination plant in Kuwait with a daily production capacity of 486,400 cubic meters of water. The plant is MED-TVC with 10 x MIGD units in total 107 MIGD. But most important is the ability to lower the process power consumption to 0.9 kwh/m3 with GOR 11 meaning that 1 ton of steam generates 11 ton of desalinated water. Hyundai is responsible for the 1,500-MW power station. The energy for the desal plant is provided by backpressure steam from combine cycle power plant typically at 2.7 bars

14 Hybrid's Simple and Integrated A common, considerably smaller seawater intake can be used. Product waters from the RO and MED plants are blended to obtain suitable product water quality. Product waters from the RO and MED plants are blended, therefore allowing higher temperature of distillate. A single pass RO process can be used. Blending distillation with membrane products reduces strict requirements on Boron removal by RO. The useful RO membrane life can be extended. INCREASED RO PERFORMANCES: the use of warm discharge from thermal MED plants improves efficiency of RO OVERALL SEA WATER NEED : the sea water required is drastically reduced if the thermal outlet sea water is used as RO feed 14

15 Integrated hybrid Cool RO Reject and Feed to be used as a cooling source for heat reject section of distillation plants. The blend of reject stream from RO with warm seawater and blowdown from distillation or power plants reduces heavy density plume of RO outfall. An integrated seawater pretreatment and posttreatment is used for the product water from both plants. A common, much smaller seawater intake & outfall.

16 The Largest Hybrid MED-RO Fujairah MIGD MED and 30 MIGD RO Courtesy Gerard Canton

17 Sorek the Largest RO Plant Came on line October 2013, Producing 624,000 m3/d, making it the largest SWRO plant in the world today. First time use of 16 inch membranes in a large-scale facility, in an innovative vertical arrangement of the pressure vessels Proprietary 3-Center Design (pumping center, membrane center and ERS) and double line intake. Steps to minimize impacts to the environment. Courtesy Avshalom Felber Vertical Membrane Arrangement

18 Process and apparatus for partial blending of softened feed to high temperature effects of MED in order to increase TBT NF SOFTENING SYSTEM Softened feed to high temp. MED effects Reject from softening to outfall or low tem. effects Seawater to NF softening Seawater from intake to final condenser

19 Hybrid Using Nanofiltration - Membrane Softening Membrane softening technology adapted to hybrid with distillation processes could lead to a significant increase in the productivity of distillation plants as well as resulting in better process economics. As a result, the selectivity of NF membranes for monovalent and bivalent anions is significantly different as compared to regular RO membranes. Specially designed NF membranes have the capability of high rejection for divalent ions (Ca, Mg and SO 4 ), while allowing relatively high passage of monovalent ions (Cl, Na and K). Nano-filtration is a proprietary pre-treatment for MED to increase efficiency for optimizing MED operation. Thanks to the nanofiltration, the thermal efficiency GOR can be increased 19

20 Performance of NF membrane XUS

21 22

22 Performance of MSF Unit 9 of 5 MIGD Upgraded with NF operation to 7.5 MIGD Date 03/05/06 03/05/06 04/05/06 04/05/06 04/05/06 04/05/06 04/05/06 05/05/06 Time test number Brine Heater (TBT) C Distillate flow total MIGD Dist conduct 17th stage µs Dist conduct 1 to 14 stage µs Sea water flow T/h Sea water tempering T/h Recycle brine T/h Make up T/h Blow down T/h Seawater inlet stage 17 C BH condensate temp C Distillate temp stage17 C NF SW SUPPLY M3/H NF PRODUCT M3/H NF SW supply C C DESAL CONDITION 116º C NF I/S Stages 1&2 vents open 116º C NF I/S Stages 1&2 vents open 116º C NF I/S Stages 1&2 vents open 116º C NF I/S Stages 1&2 vents open 116º C NF I/S Stages 1&2 vents open 116º C NF I/S Stages 1&2 vents open 116º C NF I/S Stages 1&2 vents open 116º C NF I/S Stages 1&2 vents open

23 NF-MED Coupling with NPP steam/water transformer The heat for the MED unit will be supplied from steam water transformer. The hot water will be sent to a flash chamber and will generate the required steam to the MED unit. From the flash chamber the colder water will be pumped back to the steam/water transformer. In order to improve the overall specific energy consumption a nanofiltration unit has been added to treat the feed water to the hot group. The NF unit will remove all the sulphates dissolved in the feed, allowing to operate the MED at a top brine temperature of 80 C without scaling problems.

24 ROSATOM with Turbine K-1200, Power Machines JSC Example of specific solution is based on the extraction steam from Turbine K-1200, Power Machines JSC can be effectively used in the design desalination capacity for each NPP of 170,000 m3/day, with the amount of steam available from extraction point III and IV, we could use the MPa and.471 MPa steam and send by pipelines a reasonable distance to drive the Steam Transformers. The Steam Transformer provides clean steam for thermocompressors TVC. Steam Transformer also prevents from chemical contamination of the steam as is re-boiling pure water vapor-steam to drive MED- TVC. 25

25 NPP with NF-MED steam at 92 C and 20 effects with GOR 16 using hot water transformer.

26 Use of low pressure extraction steam The steam from extraction section V at.119 MPa cannot be send directly to MED, because of high volume of steam at lower pressure the piping would be too big with very large diameter, making economically not practical. We would suggest a novel but simple solution adopted for NPP Power-MED system. We would propose an indirect energy transfer. The power plant extraction steam at 119 MPa is initially exchanged in a separate smaller condenser to a closed cooling water circuit. The heat absorbed by the water is transferred by pipeline to MED flashing chamber to provide steam for the first effect of MED. 28

27 The challenge is coupling of nuclear energy to MED thermal desalination plants through hot water loop Sketch: Nano-filtration as a pre-treatment for MED

28 Use of low pressure extraction steam The significant benefits of such a design are: Elimination of the large steam piping from power plant to the evaporators, including heat and steam loss. Elimination of the MED steam transformer as there is no need for a thermocompressor. The condensate is reflashed deaerated and totally returns from first effect. No hydrazine contamination of the product. The heat can be transferred in water pipeline a long distance allowing power and water islands to be at optimum location. 30

29 NF-MED desalination with hot water loop 32

30 NF-MED desalination with hot water loop The heat for the MED unit will be supplied from hot water loop. The hot water will be sent to a flash chamber and will generate the required steam to the MED unit. From the flash chamber the water colder will be pumped back to the nuclear hot water transfrormer. In order to improve the overall specific energy consumption a nanofiltration unit has been added to treat the feed water to the hot group. Again the NF unit will remove all the sulphates dissolved in the feed, allowing to operate the MED at a top brine temperature of 80 C or higher without scaling problems. With this configuration the overall specific energy consumption, calculated as the ratio between the heat provided to product flow will be kj/kg or PR Without the NF in operation the overall specific energy consumption, ratio between the heat taken from the hot water and the product flow will be kj/kg.

31 Conclusions Application of integrated hybrid of NF-MED and RO couple with nuclear energy offers great opportunity. Desalination: the Sustainable Solution and Hope for the Future Generations depends on future innovation and the best use of nuclear and renewable energy and will contribute in search for solutions to make desalinated water affordable to all peoples of the global village