435 m 2 collectors on roof of building 2
DESCRIPTION
Solar powered adsorption cooling cum desalination. ME Dept., NUS. A pilot teaching facility at LF027, Building 2. A pilot AD desalination cum cooling plant for teaching and research. 435 m 2 Collectors on roof of building 2. AD working principles (KAUST/NUS patent) - PowerPoint PPT PresentationTRANSCRIPT
Professor Kim Choon NG, Mechanical Engineering, National University of Singapore, and Visiting Professor Water Desalination and Reuse Centre, KAUST, SA Email: [email protected] [email protected]
Solar powered adsorption cooling cum desalination
Adsorption-triggered-evaporation Desorption-activated-condensation
25-33°C
28-36°C
55-85°C, from Solaror waste heat
45-75°C25-30°C28-33°C
7-28°C12-33°C
Mesoporous adsorbent
SiO3.nH2 O , 800m2/g
Cooling power, Tchilled = 7-20°C, 25- 32 Rtons/tonne
Potable water TDS <10ppm, pH =7.3,±0.15 to 12 m3/tonne.day
Advantages:-Produce two useful effects with low-temperature heat input,-low specific energy (electric) consumption (1.38kWh/m3), -no major moving part, inexpensive materials for construction
• The daily average radiation in Thuwal (KAUST) is about 22 MJ/m2.day (latitude λ=22o , sunshine hours from 9 to 13 h/day)
• Estimated thermal rating is 1300 kWh/m 2.year, as compared with 925 kWh/m 2.year @ 65o C in Singapore .
• Recommend to use tube collectors because (i) it is easy to handle, (ii) it reduces the dust accumulation – dust particles will slide over the tube curvature whilst those accumulated on top could be blown over by strong wind.
Provide shading that reduces heat stress in green houses.
5
Exhaust Gas
Why Co-Generation ?
Electricity (- max at 1.3 MW)
Steam (4800 kg/h)
• Cooling (7o C and 15-18
0C)• Water
(5 l/m2 .day)
Electricity from grid ( )42.0th
“Kettle” Boiler (8 bar)
Electrically-operated decicant dehumidifier
Gas Turbines x 2 units of 700 kW
Temperature cascaded utilization of exhaust energy with AB_AD chillers
Waste heat operated boiler (8 bar)
Steam driven AB/AD chillers
375 to 500oC
125o C
Primary fuel, (Town gas)
TriGen EUF =0.85- Thermally-driven design
Conventional EUF=0.52
DARI’s energy needs
Conventional approach
Co-generation cum solar
Primary fuel
diesel
electricity
7
Grid of KAUST
Electric chillers (400 Rtons)
CWS =7 C
Gas Turbines (2x 700 kW)
360 kW1000 to 1200 kW
Steam(177 C, 8.3 bar)
AB chillers (COP 0.9 to 1.1) giving 800 to 1000 Rtons
AD Chillers (COP =0.5 to 0.65) giving 120 to 150 Rtons
500-600 kW for use in DARI
CWS = 9-10 C
CWS = 14 to 18 CWater production75 m /day
Further waste heat recovery
50-60 kW 20 to 25 kW
Seawater Cooling Towers (1200 Rtons)
40 – 55 kW
Exhaust leaving at < 125 C
8
Sea Water Tank
Pre-treatment sea water tank
Sea water feeding line
9
Reactor Bed Condensate drainage
Collection tank
Release Valve
Condenser
11
Pretreatment
tank
Hot water
storage Waste heat recovery
from exhaust Fresh water
storage
Post treatme n t
tank
Sea water
Silo-type adsorber-desorber beds
Condenser and evaporator Cooling water system
valves
E x haust gas
2 0 0 to 25 0 C
12
Reaction bed tower
Evaporator
Condenser
Purified water
storage tank Reaction bed tower
1
2 3
4
5
d d
H
Can the AD cycle scale to a commercial size ? – to work closely with industry partners of KAUST
14
15