Concentrated Solar Energy for Hydrogen and Syngas Production

Transcription

1 Concentrated Solar Energy for Hydrogen and Syngas Production Prof. Dr. José R. Simões-Moreira SISEA Alternative Energy Systems Laboratory Escola Politécnica of USP November 13th, 2017 FAPESP The São Paulo Research Center (Brazil) 1

2 Introduction Hydrogen gas has all the good characteristics of a clean fuel; Hydrogen gas is an alternative to store solar energy in its chemical bounds, Most common path to store solar thermal energy in the form of hydrogen are: Solar steam-reforming; Solar water-splitting thermochemical cycle; Electrolysis driven by PV panels. 2

3 Thermochemical routes for hydrogen production (Steinfeld, 2005) Figure 8: Thermochemical ways to use Concentrated Solar Energy (Steinfeld, 2005) 3

4 Solar water-splitting thermochemical cycle The solar water-splitting thermochemical cycle. The cycle has 2 or more steps. 4

5 Solar water-splitting thermochemical cycle 5

6 High-Flux Solar Simulator 6 6

7 High-Flux Solar Simulator Used in materials and component tests for thermal and thermochemical applications at high temperatures; Designed to simulate the directional, spatial and spectral distribution of the concentrated solar radiation obtained in the concentrator focal point; Radiation source: high-power xenon or argon arc lamp in association with accurate optical reflectors. 7 7

8 On going solar simulator project 8 8

9 TEST PROCEDURE Challenge: obtain a radiative flux map of high density at a small target and in which the constant flux lines are concentric circles; Problem: make the correct geometrical adjustment of the arc lamps and reflectors; Solution: use of measurement techniques to evaluate the apparatus optimization; Quantity to be measured: spatial distribution of radiative flux (W/m²) on the simulator s focal plan; Tools: high-resolution digital camera and heat flux sensor. 9 9

10 INICIAL SETUP Radiative Flux Map Disapproved setup Adjustments Mapping FINAL SETUP Disapproved setup Adjustments Mapping Adjustments Mapping

11 Tuning technique it will define de cavity aperture size Bode S. J. et al 11

12 PROCESSING OF RESULTS Radiative flux map (MW/m 2 ) at the focal plan during the solar simulator operation PSI Paul Scherrer Institut Solar Technology Laboratory Constant flux lines are concentric circles, what indicates satisfactory calibration and optical quality of the reflectors associated with arc lamps 12 12

13 Iron oxide redox pair Prelimary tests The water-splitting thermochemical cycle of iron oxide redox pair: Fe 3 O 4 1 3FeO + O 2 2 endothermic process, reaction temperature at 2300ºC 3FeO H O Fe O + H exothermic process, reaction started at temperature 400ºC Highly endothermic, need a lot of energy 13

14 Iron oxide redox pair An alternative pathway, to avoid the high temperature to reduce the iron oxide: Fe O + 3C 2Fe + 3CO 2 3 The temperature of reaction is about 1000 C The oxidation process: Fe + H2O Fe3O4 H The temperature of reaction is in the range from 300 to 1000 C 14

15 Experimental In the experimental study, two different experiments were performed: One of these studies was to obtain the mass variation at five different reaction temperatures (600, 700, 800, 900, and 1000 C) The kinetics of iron oxidation by steam was studied by the thermogravimetric analysis technique (TGA). This experiment was carried out at three different temperatures (600, 800, and 1000 C). The sample were iron SAE 1020 plate 2mm thickness. 15

16 Experimental set-up Fig. 2 The oxidation experiment set-up [8]. 16

17 Experimental set-up Fig. 3 The second experiment set-up to study the kinetic of iron oxidation by steam [8]. 17

18 Kinetics models For the chemical kinetics analysis, the simplified models describing high temperature oxidation were used Parabolic model: W 2 C k p t Linear model: Arrhenius Law: k W A k 0 L t exp E RT Chemical phase analysis Optical microscope and Scanning electron microscope (SEM) Energy-dispersive X-ray spectroscopy (EDS) Raman spectroscopy 18

19 Results First experiment results are showed in table 1. 19

20 Results Thermogragravimetric analysisresults: Experimental investigation of iron November oxidation to 13th, produce 2017 hydrogen - FAPESP The São Paulo Research Tiago Center Gonçalves (Brazil) Goto - EPUSP J. 20

21 Results Fig. 5 The oxide layer at the three different temperatures a) 600 C ; b)800 C; c) 1000 C. 21

22 Results The result of chemical phrase analysis 22

23 Conclusion on the redox study In this work, the main goal was studied the iron oxidation by steam and the influence of temperature and oxidation kinetics. Then it was possible to draw the following conclusions: The weight gain per unit area increases proportionally with the temperature; Oxidation rate is higher at the first hour due the formation of oxide layer on the surface. That oxide layer forms a barrier that makes it difficult to continue the oxidation process; The oxide layer of the samples oxidized at temperature 1000 C presented cracks and porous layer. That result can explain by the linear oxidation behavior, while the oxidation at 600 C and 800 C shows a parabolic behavior; The oxidation is slower at low temperature than at high temperature. It is due to the oxide layer formed on the surface. 23

24 REFERENCES [1] Abanades S., Charvin P., Flamant G., Neveu P., Screening of water-splitting thermochemical cycles potentially attractive for hydrogen production by concentrated solar energy. Int J Hydrogen Energy; [2] Steinfeld A., Solar thermochemical production of hydrogen a review, Solar energy; Solar Energy; [3] Steinfeld A., Solar hydrogen production via two-step water-splitting thermochemical cycle based on Zn/ZnO redox reactions. J Energy; [4] Palumbo R., Lédé J., Boutin O., et al., The production of Zn from ZnO in a hightemperature solar decomposition quench process I. The scientific framework for the process. Chemical Engineering, v. 53, n14; [5] Nakamura T., Hydrogen production from water utilizing solar heat at high temperatures, Solar Energy; 1977 [6] Charvin P., Abanades S., Flamant G., Lemort F., Two-step water-splitting thermochemical cycle based on iron oxide redox pair for solar hydrogen production, J Energy;

25 REFERENCES [7] Goto T. G., Mourão M. B., Simões-Moreira J.R., Estudo de rota Termoquímica para produção de gás hidrogênio em redox de óxido de ferro Solar water-splitting thermochemical cycle to produce hydrogen with redox iron oxide, Agrener GD 2015: 10º Congresso sobre geração Distribuída e Energia no Meio Rural; 2015 november 11-13, São Paulo, Brazil. [8] Goto T. G., Estudo experimental do processo de oxidação do ferro com vapor de água para a produção de gás hidrogênio Experimentally study of iron oxidation by steam to produce hydrogen [Master dissertation]. São Paulo, Brazil: Escola Politécnica da Universidade de São Paulo; [9] Lafuente B, Downs R T, Yang H, Stone N (2015) The power of databases: the RRUFF project. In: Highlights in Mineralogical Crystallography, T Armbruster and R M Danisi, eds. Berlin, Germany, W. De Gruyter, pp 1-30 [10] Stehle, R. C., Bobek, M. M., Hooper, R., & Hahn, D. W. (2011). Oxidation reaction kinetics for the steam-iron process in support of hydrogen production. International Journal of Hydrogen Energy, 36(23),

26 REFERENCES [11] Colomban, P. Potential and Drawbacks of Raman (Micro)Spectrometry for the Understanding of Iron and Steel Corrosion. New Trends and Developments in Automotive System Engineering, p , [12] Go, K. S.; Son, S. R.; Kim, S. D.; Kang, K. S.; Park, C. S. Hydrogen production from two-step steam methane reforming in a fluidized bed reactor. International Journal of Hydrogen Energy, International Association for Hydrogen Energy, v. 34, n. 3, p , [13] Singh, A.; Al-Raqom, F.; Klausner, J.; Petrasch, J. Production of hydrogen via an Iron/Iron oxide looping cycle: Thermodynamic modeling and experimental validation. International Journal of Hydrogen Energy, v. 37, n. 9, p , [14] Lorente, E.; Peña, J. A.; Herguido, J. Kinetic study of the redox process for separating and storing hydrogen: Oxidation stage and ageing of solid. International Journal of Hydrogen Energy, v. 33, n. 2, p ,

27 We gratefully acknowledge support of the RCGI Research Centre for Gas Innovation, hosted by the University of São Paulo (USP) and sponsored by FAPESP São Paulo Research Foundation (2014/ ) and Shell Brasil. 27

28 Thank you! 28