IEA Solar Heating and Cooling Programm - NachhaltigWirtschaften.at

IEA SHC Task 38 Solar Air Conditioning and Refrigeration Subtask C Report, Date: 13.01.2009
Contents
1 Introduction .................................................................................................................... 4
1.1 General ................................................................................................................... 4
1.2 Thermally driven Heat Pumps ................................................................................. 4
1.3 Comparison of Heat Rejection Technologies .......................................................... 9
1.3.1 Dry Cooler........................................................................................................ 9
1.3.2 Wet Cooling Towers........................................................................................10
1.3.3 Hybrid .............................................................................................................11
1.4 Climatic Conditions ................................................................................................12
2 Wet Cooling Tower - Operation.....................................................................................16
2.1 Nutrients and Biofilm ..............................................................................................16
2.2 Water consumption ................................................................................................16
2.3 Water treatment .....................................................................................................17
2.4 Aerosols in the Waste Air.......................................................................................17
2.5 Electricity Consumption..........................................................................................17
2.6 Anti freeze..............................................................................................................17
2.7 Part Load Operation...............................................................................................17
2.8 Maintenance...........................................................................................................18
3 Wet Cooling Tower - Process Calculation .....................................................................19
3.1 General aspects.....................................................................................................19
3.2 State of air and temperatures inside the cooling tower...........................................20
3.3 Example .................................................................................................................24
4 Legionella......................................................................................................................25
4.1 Legionellosis ..........................................................................................................25
4.2 Conditions of Legionella Growth.............................................................................26
4.3 Monitoring of Legionella and Micro-Organisms ......................................................27
5 Avoidance of Legionella and Micro Organisms..............................................................29
5.1 Chain of Events......................................................................................................29
5.2 Design and Operational Measures to Avoid Legionella ..........................................29
5.3 Water Treatment with Disinfectants .......................................................................30
5.4 Disinfection by UV-Radiation..................................................................................31
5.4.1 General ...........................................................................................................31
5.4.2 Mechanism of destruction ...............................................................................33
5.4.3 UV-C light production ......................................................................................33
5.4.4 Market available products ...............................................................................33
5.5 Water disinfection by metal ions.............................................................................35
5.5.1 Pre-Test of the method ...................................................................................35
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