From Waste to Wealth: Commercial recovery of products from geothermal fluids

Transcription

1 From Waste to Wealth: Commercial recovery of products from geothermal fluids NZGA & HERA Seminar 25/7/14 Ed Mroczek, Melissa Climo & Brian Carey Wairakei Research Centre PB 2000 Taupo New Zealand

2 Geothermal Resources Strategic Value Electricity ~13% Heat ~ TJ/a

3 Water Rock Interaction Saturated with minerals Saleable products?

4 Major Engineering Challenge Scaling & Corrosion Above surface plant & wells Commercial Opportunity in the recovery of by-products?

5 Geothermal Brines Mineralized But variable composition Dilute High Fluid Volumes Wairakei - 180,000 t/day reinjected 72 Olympic sized pools! $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $

6 Wairakei Brine Total dissolved solids 4 kg /tonne 97% 4 highest Silica 600 g/t 108 tonnes/day Lithium 11 g/t 11 t/day Li 2 CO 3

7 Silica Example Limits Heat Extraction Generation Low grade downstream uses (including mineral extraction) Costly problem Multi B$ industry high tech to low grade uses Good Candidate for extraction?

8 Silica Extraction Investigated Before? 6 different technologies (NZ alone) $M large scale pilot plant ECNZ silica sol; quality product for high tech Tasman precipitated silica for paper BUT NO COMMERCIAL PROCESS! WHY? Calcium silicate 1975 Silica Sol 1990s

9 Lithium Example Assume 50% recovery 5 tonnes/day Li 2 CO 3 $8000/tonne Li 2 CO 3 $16M/annum But need to get rid of silica!! Annual World Sales Li 2 CO 3 >1$B/annum

10 Lithium Extraction Investigated Before? A.M. Kennedy 1957 Wairakei Commissioned 1958 Innovative Technologies Field and Lab Studies Me circa other trials (NZ) Small lab scale Kennedy s work left on the shelf! WHY?

11 Barriers to Implementation Lack of knowledge potential uses & technologies Technologies not economic or not developed Insufficient market drivers Silica needs to be removed Competitive products Modest interest for diversification (Bloomquist, 2006; Bloomquist and Povarov, 2009)

12 Barriers to Implementation Technological Low concentrations of dissolved minerals large volume of liquid to process cheap technology or be highly valuable But processes exist now which are viable Markets What to do with 40,000 t/yr of silica from Wairakei? dump or make use of down stream uses? Financial & Market Risks; Regulatory risks; who owns minerals? Industry Involvement What about courage & knowledge; NZ companies not up to it?

13 Contact Energy Wairakei Bioreactor H 2 S removal Born out of need! Innovative & courageous (world first) Researched for ~ decade (small pilot plant) Processing 1,000,000 t/day Cost ~ $ 30M

14 Financial Barriers Geo-Heat Center, Klamath Falls, Oregon, USA Appreciable savings can be achieved by adopting integrated systems that offer a higher utilization factor But where is the evidence? What is stopping this? Geothermal Well $5-15M

15 Silica treatment vs. Extraction technical and economic evaluations? Cold Injection Acid Dosing

16 Barrier to Downstream Uses Prawn Wagging the Power Station

17 GNS W2W Proposal $4M over 4 years (2013) Positive Economics Key Driver for Commercial Success (and no need for yet more silica extraction research) Fluid Composition 1. Commercial Opportunities or overcoming the barriers! Technological Review Market Drivers Regulatory Industry Buy-In ~ $500k 2-4. Technological Development & Financial Modelling Lithium Gases Trace metals Best options for Investment

18 $400k over 2 years GNS W2W Proposal $4M over 4 years Positive Economics Key Driver for Commercial Success 1. Commercial Opportunities or overcoming the barriers! Fluid Composition Technological Review Market Drivers Regulatory Industry Buy-In X ~ $500k $400k X 2-4. Technological Development & Financial Modelling Lithium Gases Trace metals Best options for Investment

19 From Waste to Wealth Commercial recovery of products from geothermal fluids Review of processing technologies Compilation of geothermal fluid composition NZ regulatory assessment From Waste to Wealth Market analysis Stakeholder workshop Opportunities & Barriers: Final Report

20 Collect Data for Future Financial Modelling Financial Models by Scion (after WoodScape Project for the Timber Processing Industry)

21 From Waste to Wealth Commercial recovery of products from geothermal fluids Technological Review (Oct 2013) Professor Wei Gao Chemical & Materials Engineering University of Auckland Regulatory Review (May 2014) Professor Barry Barton Te Piringa Faculty of Law University of Waikato Markets (July 2014) Alistair Hill Hill Technology & Management Ltd

22 From Waste to Wealth Commercial recovery of products from geothermal fluids Technological Review Underway MSc x2 under Professor Wei Gao supervision Scope Major SiO 2, Li, Cs, Rb and B & CO 2 purification trace elements (economic extraction less likely) Competing processing technologies Trialled/Applied on geothermal fluids and gas streams Disadvantages/advantages Synergies with geothermal waste heat Product being produced Evaluate rough order costs (± 50%) Identify suitability of residual fluid for disposal (reinjection?)

23 From Waste to Wealth Commercial recovery of products from geothermal fluids Regulatory Framework Implication for commercial operators Legal Analysis Rights under the RMA Rights under other Acts and common law Treaty rights Law reform Market Drivers Markets and products with most potential Analysis for products from technological review (where available) Market size & development Growth, supply, demand and profitability Cost structures, pricing, competitive products

24 From Waste to Wealth Commercial recovery of products from geothermal fluids What Can You Do? Provide Peer Review Important technologies/products/markets/legal may be missed Put data in the public domain Participate in the Workshop - July 2015

25 Acknowledgements We would like to thank all the Power Companies, Maori Trusts, Regional Councils and MBIE for supporting this research through providing information and funding.