Hydrogen Generation Programme at ONGC Energy Centre

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1 Hydrogen Generation Programme at ONGC Energy Centre D. Parvatalu ONGC Energy Centre IHFC, Jodhpur

2 Outline of Presentation Introduction Thermochemical cycles Technical Challenges ONGC Energy Centre Hydrogen program Cu-Cl Cycle Iodine-Sulfur cycle Current status Conclusions

3 ONGC Energy Centre ONGC Energy Centre set up by ONGC is engaged in R&DD on clean Energy Technologies Hydrogen Generation Uranium Solar Geo-Thermal Bio-technology Energy Recovery / Efficiency relevant to hydrocarbons ONGC Energy Centre is located at Delhi, with research centres also located at Ahmedabad, Dehradun and Panvel. Hydrogen facility is being set up at Vadodara

4 Key Areas of R&DD Hydrogen Thermochemical methods for splitting of water to generate Hydrogen Other methods for generation of Hydrogen, heat source integration Materials, components and equipment for Hydrogen generation SOFC development Hydrogen Storage Solar Power generation, storage, specialized coatings, applications in oil/gas sector Bio- Technology for Energy _ Conversion of sub-surface unrecoverable oil / coal / lignite to Methane -- Controlling Reservoir souring Uranium Subsurface exploration Development of process for In-situ Leaching (Chemical, Microbial, hybrid) Geothermal Assessing potential in sedimentary regions for power and heat Others Energy Efficiency / Energy Recovery relevant to oil & gas sector

5 Thermochemical Water Splitting Water Chemical Reactions Heat ONGC Energy Centre has been pursuing R&D on Iodine- Sulfur and Copper-Chlorine processes since 2007

6 Technical Barriers Technologies are still at Bench scale development Material selection & availability Corrosion testing facilities at high temperature Cost-effective catalysts and membranes Continuous operation of electrochemical systems Energy efficient separations / purifications Long term performance data of integrated systems Heat source identification, selection and Management Design & indigenous Development of equipment ONGC Energy Centre decided to start indigenous technology development in 2007

7 OEC Approach Development of Thermochemical Hydrogen Generation program Copper Chlorine(Cu-Cl) Cycle Iodine-Sulfur (I-S) Cycle Proof of Principle Experiments Closed loop I-S Cycle Partially open loop I-S cycle Additional Bridge the gap Studies/Supporting Studies to develop membranes, materials etc Close/open-loop Lab scale engineering studies Further improvement / Scale up Pilot Scale Demonstration

8 New Ideas Membranes Fuel cells Molten salts Techno economic Analysis Liquid Fuels Value added Products Hydrogen Generation Multiple Options Safety Development of Sensors Components for process & equipment Materials for Construction Corrosion Studies C S P Pilot Demonstration Alternate Electrodes PV

9 Materials Development Process improvement for Energy efficient separations, Alternate options etc., Affordable Catalysts Membranes, electrodes, development Heat Source development and integration Current focus Scale up / Long term performance of integrated metallic systems H.T-H.P Corrosion testing Electrochem cell operation in continuous mode Simulations/modeling, Flow sheet development

10 New Copper-Chlorine Cycle by ICT-OEC

11 New Cu-Cl cycle by OEC-ICT Reactions 1 Hydrogen Generation (475 ± 25 C) 2 Electrochemical (ambient temperature) 3 Drying (120 ± 20 C) 4 Hydrolysis (375± 25 C) 5 Decomposition (475 ± 25 C) 6 Oxygen Generation (500 ± 25 C) Cu-Cl Cycle 2Cu (s) + 2HCl (g) 2CuCl (l) + H 2(g) 4CuCl (l) 2CuCl 2(aq) + 2Cu (s) 2CuCl 2(aq) 2CuCl 2(s) CuCl 2(s) +H 2 O (g) CuO (s) + 2HCl (g) CuCl 2(s) CuCl (l) +½ Cl 2(g) CuO (s) +½ Cl 2(g) CuCl (l) +½ O 2(g)

12 Progress: Cu-Cl cycle A new multi-step Cu-Cl cycle has been established. Patented the process in 7 countries viz., USA, Canada, UK, Japan, China, Korea and India An integrated lab scale engineering facility in metallic system has been developed and demonstrated for H 2 generation@ 25 lph for Cu-Cl cycle using indigenous resources. Long term performance data being generated for last 3 years for designing a larger plant for H2 generation@ 12 M.T / Y in conjunction with Solar thermal plant at OEC A new electrochemical cell has been designed / fabricated for CuCl electrolysis (60A stack developed) and already patented in 5 countries viz., USA, Canada, UK, Japan, China Developed cost-effective alternative materials for platinum viz., MMO coated Ti, Graphite electrode materials that yielded 700 ma/cm 2 current density at ~1.0 V; further integration with main cycle in progress Created High Temperature corrosion testing facilities for screening materials with and without coating in molten CuCl environment at 550 o C Developed indigenous polymeric membranes for electro-chemical process Developed molten salt system for application in Cu-Cl cycle in conjunction with solar heat Designed Pressure Swing Distillation system for HCl-Water separation process

13 Schematic of Closed-loop Cu-Cl cycle

14 Major Breakthrough in Cu-Cl cycle... Overcame Limitations of usual designs : Continuous removal of copper Bigger particle size of obtained copper Scale up Pt costly electrode Competing reaction Advantages of new reactor Provision for continuous removal of copper 5-20 μm particle size obtained Easy for scale up Pt replaced by low cost graphite / MMO coated electrodes High mass transfer rate 14

15 60 A Electrochemical stack in operation MMO- coated Ti electrodes Achieved maximum cathodic current density with MMO coated Ti anode was 710 ma/cm2, at 1.00 ± 0.1V, 5 N HCl, 0.4 N CuCl, surface area ratio of anode to cathode: 11

16 Performance evaluation indigenously developed anion exchange membrane against commercially proven Snow Pure membrane in Cu-Cl cycle Indigenous anion exchange membrane based fluorinated hydrocarbon developed at CSMCRI Electrochemical Cell for CuCl electrolysis Results obtained under operating conditions of Cu-Cl cycle LSV 50 mvs -1 Experiment Applie d Voltag e (V) Avg. Current obtained (A) Expt Expt Expt (A) CSMCRI Membrane Avg. current from three experiments (A) Avg. Cathodic current density (ma/cm 2 ) (C) Commercially available Snow Pure membrane Expt Expt Expt

17 Molten salt integration with Cu-Cl cycle Molten salt system developed Ternary-1 temperature range from 144ºC (melting temperature) to 620ºC (degradation temperature). Ternary-2 temperature range from 120ºCto 578ºC. Conceptual schematic of the double shell reactor 17

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19 Iodine- Sulfur (I-S) Cycle O 2 H 2 H 2 SO 4 H 2 O + SO 2 + ½ O 2 ΔG=-137 KJ/M; ΔH=271 KJ/M 2 HI H 2 + I 2 ΔG= 24 KJ/M; ΔH= 12 KJ/M 850 C Decomposition H 2 SO 4 Decomposition HI 450 C SO 2 I 2 Concentration H 2 SO 4 H 2 0 Vaporization HI I 2 + SO H 2 O H 2 SO HI ΔG= -41 KJ / M; ΔH= KJ / M Bunsen Rxn 120 o C Over all réaction H 2 O H 2 + ½ O 2

20 Achievements: I-S cycle Established facility for I-S closed-loop operation in Quartz system using combination of electrochemical and thermal reactions. Developed a novel non-platinum based catalyst systems for H 2 SO4 decomposition that is proven under prevailing operating conditions Developed High Temperature-High Pressure (HTHP) bayonet type metallic reactor for pilot scale operation equivalent to 150 lph in terms of H 2 generation was successfully designed, fabricated & commissioned at IIT-Delhi using inhouse expertise and indigenous resources A suitable catalyst system has been developed for HI decomposition section that is found to be stable for prolonged periods of operation for 600h~. Developed stand alone Open Loop I-S process components for hydrogen generation involving H 2 S incineration leading to process Integration Developed Nafion equivalent Cation-exchange membrane that has potential to integrate with main cycle.

21 Electrochemical Bunsen Reaction Anode reaction: SO 2 + 2H 2 O H 2 SO 4 + 2H + + 2e; E 0= V Cathode reaction: I 2 + 2H + +2e 2HI ; E 0= V Total reaction: SO 2 + 2H 2 O + I 2 H 2 SO 4 + 2HI 1000 x Scale up operation of Bunsen reactor with indigenously prepared membrane and electrodes in progress

22 Electro-Electro Dialysis HI enrichment Cation Exchange Membrane (Indigenous) Stack Electrode (Graphite) + Anolyte (Dilute) I 2 I - I - H + I 2 -- Catholyte Conc CELL Achieved above azeotropic HI conc n (~7N) in Catholyte at R.T- 60 o C. Current efficiency 80-85% Graphite Electrodes and Nafion / Indigenous membrane at Lab scale Depleted HIx Enriched HIx Further scale up 1000x work in progress using Indigenously prepared Nafion equivalent membrane and MMO coated Titanium electrodes

23 Nafion TM and Indigenous Membrane Indigenously developed Cation Exchange Membranes bear excellent mechanical, thermal, oxidative and acid-base (20 M H 2 SO 4 or NaOH) stabilities. Polarization Studies Comparative study of Nafion and Indigenous CEM Membrane Water content (%) Ion-exchange capacity (meq./g) Conductivity (S cm -1 ) Nafion LSV curves for anodic Cu + oxidation and cathodic hydrogen evolution 50 mvs -1 SCP Conclusion: The performance of Nafion-117 and OEC membrane are almost equivalent for CuCl/HCl electrolysis

24 Ceramic Gas separation Membranes development Laboratory setup of gas permeation study

25 Closed-loop Experimental facilities at IIT-D

26 Open loop I-S cycle H2S incineration H 2 S + 3/2 O2 SO2 + H2O Bunsen Reaction 2H 2 O + I 2 + SO 2 H 2 SO 4 + 2HI HI decomposition 2HI H 2 + I 2

27 OEC-IIP Open-loop Experimental facility: IIP, Dehradun H2S Incinerator set up

28 Current status: I-S cycle Studies on Closed/Open loop Experimental facilities is continued for base line data generation for further scale up in metallic loop Initiated action on reactor design, materials selection based on corrosion studies, to generate inputs to metallic system Initiated preliminary studies on developed zeolite membranes for separation of O 2 and SO 2 in progress Initiated work on integration of Open-loop I-S process involving H 2 S incineration to generate SO 2 in conjunction with classical Bunsen, HI Reactive distillation Scale up of Electrochemical Bunsen and Electro-Electrodialysis units in progress using indigenously developed membranes Initiated development of High temperature testing facility for screening materials for open and close-loop operations Initiated studies on exploring alternate options for reducing temperature in H2SO4 section and direct electrochemical decomposition of HI.

29 New Initiatives: Alternate Approach in HI section OEC and BITS-Goa have initiated work on Electrochemical decomposition of HI an alternate route to HI section in I-S cycle

30 New Initiatives: Alternate Approach in H2SO4 section OEC has initiated various alternate approaches to reduce heat load in H2SO4 section FeSO4 route indicated a good promise for further investigations as it reduces decomposition temperature substantially to about 600 o C. The possibility for membrane assisted decompositions is also being pursued as it can lower H2SO4 decomposition to around 620 o C as reported in recent literature. Schematic representation of catalytic membrane reactor

31 CORROSION TESTING IN MOLTEN Cu-Cl ENVIRONMENT Coupons before and after test

32 Corrosion studies on SiC in I-S open-loop process Gravimetric studies and visual examination SEM analysis: (a) & (b) Bunsen; (c) and (d) HI decomposition Fresh and Exposed coupons

33 Conclusion OEC is developing the I-S and Cu-Cl Thermochemical water splitting cycles for large scale production of Hydrogen as well as Oxygen, to meet the emerging demand for transport sector and other energy requirements in the country. OEC and collaborators have made significant strides in developing the processes using a combination of Electrochemical and thermochemical routes OEC in association with partner organizations have developed Internationally Patented Thermochemical water splitting process, products based on indigenous equipment and facilities. OEC in association with partner organizations have also developed membranes for various electrochemical applications with indigenous sources Current focus is on further scale up of integrated metallic systems and addressing related issues to enable continuous operations OEC is exploring possibility for reduction in I-S process operating temperature with alternate approaches including direct electrochemical HI decomposition OEC is working on Demonstration of Integrated Hydrogen Production facility comprising Concentrated Solar Thermal Power Plant, Molten Salt Storage and Closed Loop Cycle for Thermochemical Splitting of Water, at a pre-pilot level capacity of about 12 M T/ year.

34 Thank You all for kind attention & our collaborators for support