ANALYSIS OF HYDROGEN ELECTROLYZER WORK

Transcription

1 Silesian University of Technology Institute of Power Engineering and Turbomachinery ANALYSIS OF HYDROGEN ELECTROLYZER WORK Janusz Kotowicz Włodzimierz Ogulewicz Daniel Węcel Michał Jurczyk Power Engineering and Environment 2015

2 1. Introduction A huge amount of pollutants is emitted all the time to the atmosphere from combustion and transformation of fossil fuels, The demand on the electricity in the world is still growing, Renewable energy sources, used to power generation, are one of way to reduce emission of CO 2 to the atmosphere, Another way to decrease of CO 2 emission is produced and storage hydrogen, Hydrogen production is still based primarily on the use of fossil fuels, by the reforming of natural gas and gasification of coal. 2

3 1. Introduction Hydrogen can also be produced based on electrolysis of water. In that case, it is not to necessary use fossil fuels, and hence there is no environmental degradation associated with mining and processing of these fuels, because the energy for hydrogen generators can be derived from renewable energy sources. Hydrogen in this process is formed from the water as a result of the reaction occurring at the cathode and anode of the electrolyzer cell. Electrical energy is used in this case to separate water on the two basic components, the hydrogen and oxygen. A: Oxidation process K: Reduction process For different type of elecktrolyzers reaction can also be different. 3

4 2. Objects of study Tab 1. Technical data of analyzed hydrogen generator Parameter/ Quantities Value Purity of hydrogen (dry gas) 99,999% The maximum effectiveness at standard conditions Water consumption Max hydrogen output pressure Max input power Dimensions Mass ~0,9 dm 3 /min 1,0 g / 1 dm 3 of hydrogen 0,5 MPa 600 W 33/18/43 cm 12 kg 4

5 2. Objects of study Fig. 1 Hydrogen generator TsvetChrom

6 3. Construction of hydrogen generator measurement station Fig. 2 Construction of a hydrogen generator measurement station ( 1- Water tank, 2- Electrolyzer 21, 3- Electrolyzer 22, 4- Moisture separator, 5- Set of filters, 6- Cooler, 7- Valve, 8- Thermal flow meter) 6

7 3. Construction of hydrogen generator measurement station Fig. 3 Construction of a hydrogen generator 7

8 3. Construction of hydrogen generator measurement station Fig. 4 Measurement USB card 8

9 4. The results of measurements The electrolyzers efficiency was determined using the equation: η E = LHV H2 q U I 100 % Where: - hydrogen lower heating value J/l U - voltage on electrolyzer, V I - current intensity on electrolyzer, A q stream of hydrogen, dm 3 /min 9

10 4. The results of measurements The properties of electrolyzers were tested under strict conditions : Ambient temperature ~25 o C Hydrogen outlet pressure - ambient pressure Water conductivity ~1,6 µs/cm 10

11 4. The results of measurements Fig. 5 Effectiveness and efficiency of electrolyser 21 depending on its current supply Fig. 6 Effectiveness and efficiency of electrolyser 22 depending on its current supply 11

12 4. The results of measurements Fig. 7 Influence of current intensity for changing electrolyzer temperature and electrolyzer inlet water temperature 12

13 4. The results of measurements Fig. 8 General current voltage characteristic of electrolysers 13

14 5. Conclusion Hydrogen can be achieved in the electrolysis process with a very high purity equal 99,999%, According to performed measurements of the efficiency of the tested electrolyzers changing the efficiency was in the range of 50-60%., The highest efficiency was obtained at low current values. However, for the maximum values of the current efficiency was approximately 50%, Despite the fact that the characteristics of both electrolysers are very similar there are also some differences between them, therefore, a more appropriate indicator of efficiency is an indication of the efficiency of individual electrolysers instead of the efficiency of the entire hydrogen generator, The electrolysis is the most popular method of production of hydrogen from all processes which do not use fossil fuels in the hydrogen production on large and small scale and is the most forward-looking technology development in the next years, The production of hydrogen fuel must be delivered more energy than we can recover from hydrogen in later processes. The only reasonable power source for the electrolysis process in this case are renewable source of energy. 14

15 Thank You very much Acknowledgement The results presented in this paper were obtained from research work financed by the National Centre of Research and Development in the framework of program GEKON Energy storage in the form of hydrogen in salt caverns, realized in years