From Waste to Wealth: Mineral Extraction from Geothermal Brines

Transcription

1 From Waste to Wealth: Mineral Extraction from Geothermal Brines Ed Mroczek, Melissa Climo, Brian Carey, Alistair Hill, Barry Barton National Geothermal Association of the Philippines Meeting August 2016

2 Geothermal Resources in New Zealand 2 Temperatures 30 C-340 C Source of heat, steam and gas Electricity Direct heat use Tourism Source of minerals and metals Commercial recovery & sale?

3 Opportunity 3 Heated fluids saturated with minerals and metals No cost for mineral dissolution Recovery and sale of bi-products Benefits: economic, social, environmental Capability development: technologies & people $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $

4 Possible Elements / Compounds 4 Mineralised Dilute Variable composition Low concentration High volumes

5 Existing Challenges 5 Scaling & corrosion Above surface plant and wells Environmental impacts Gas and fluid discharges Fluid volumes Dump? Discharge? Down-stream use?

6 New Zealand Examples 6 Focus on treatment and remediation Inhibiting silica scale deposition Removal of As from geothermal fluids Removal of H 2 S from condensate CO 2 recovery (removal of H 2 S) Producing clean steam Silica extraction (pilot plants)

7 Focus on Product Recovery 7 Silica Severely Limits Heat Extraction Generation Low grade downstream uses (including mineral extraction) Extremely costly problem Multi B$ industry high tech to low grade uses Good Candidate for extraction?

8 Focus on Product Recovery 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?

9 Focus on Product Recovery 9 Lithium Extraction Investigated Before? A.M. Kennedy 1957 Wairakei Commissioned 1958 Innovative Technologies Field and Lab Studies other trials (NZ) Small lab scale Why was Kennedy s work left on the shelf?

10 Focus on Product Recovery 10 Extracting products from geothermal fluids is technically feasible But positive economics is the key driver for commercial success

11 Research Programme: Objectives Provide a starting point for an information resource 2. Determine the commercial potential and best technical options 3. Encourage future investment in extraction technologies for saleable products from geothermal fluids

12 Barriers to Uptake 12 Knowledge: resources, technologies, uses Technologies: developed / economically viable Economic: market drivers, competitive products Technical: removal of silica Interest: geothermal field operators

13 Examining Barriers in a New Zealand Context $200k pa

14 Waste to Wealth Core Studies 14

15 1. Geothermal Fluid Composition 15 Why? To provide sufficient detail to inform a big-picture view to economic mineral recovery potential What? Compile chemical composition of high-temperature geothermal fluids from producing geothermal fields

16 Annual Flux for example Lithium 16 Mokai 16% fluid take of Wairakei but 50% of Li Other considerations Mokai: Absolute silica concentration much higher; may need to be removed first

17 2. Regulatory Framework 17 Why? To identify adverse legal/legislative effects on a potential geothermal minerals operation What? Review of legal / legislative framework in New Zealand

18 Legal Review 18 Geothermal resources are treated as water Environmental management legislation (RMA): includes dissolved/entrained material Crown Minerals Act: uncertainty for both mining and ancillary operations Common law rights and Treaty of Waitangi: no adverse effects

19 3. Market Drivers 19 Why? To look for market opportunities What? Market review for selected target products silica, lithium, boron, caesium, rubidium, sodium, potassium, magnesium, gold

20 The Silica Market for example 20 Global demand for all speciality silica is around 2.7 million tonnes worth US$6.9 billion This includes precipitated silica, silica gel, silica sol and fumed silica precipitated silica is the driving force for growth in speciality silica and this is being driven by use in green tires.

21 The Lithium Market for example 21 Battery demand taken from six scenarios (2011) Hybridization and electrification demand not as simple as it seems Big changes since Oil price slump 2. Introduction of 48V systems

22 4. Technology Review 22 Why? To examine what processes are available and have made it to a commercially viable industrial process What? Review of competing technologies for extraction of products from geothermal fluids silica, lithium, boron, carbon dioxide, trace elements

23 Specific Techniques Discussed 23 Ion Exchange Filtration physical filtering process Filter or membrane Electrocoagulation electrical process Direct current applied to an anode / cathode array Electro-dialysis Spinels Matrix structure of atoms that can absorb other atoms of specific dimensions Ion Exchange Resins Spinels

24 Stakeholder workshop held July Integration Identified gaps, questions, feedback Key Questions: To develop a geothermal minerals industry in New Zealand: What are the success factors? How are they connected?

25 Next Steps 25

26 Next Steps 26 Fluid Chemistry fill the identified data gaps, gather more data, undertake international comparisons, and clarify sustainability

27 Next Steps 27 Technologies develop, test, adapt and/or validate extraction technologies under New Zealand conditions Integrated Plant examine process design options for integration with existing plant facilities, and determine the economics of integration

28 Next Steps 28 Legal Frameworks clarify the position of the governing Acts and their implementation Managing Business Risk examine risk profiles, explore alternative business models and deliver commercial proof

29 Next Steps 29 Market Drivers deeper/wider market analysis to inform the physical nature of the product, the price and value chain, and geographic market considerations Financial Modelling develop/adapt financial models to suit a geothermal minerals operation

30 Future 30 Government Science & Innovation funding (2016) Industry investment We are looking for International Collaboration What wealth do your geothermal fluids hold? From Waste to Wealth is a starting point to provide a framework for economic, regulatory and technical information to guide future investment More information:

31 Acknowledgements 31 Data, discussion and support Geothermal Electricity Generators Regional Councils Economic Development Agencies Industry representatives Research Funded by the New Zealand Ministry of Business Innovation and Employment Thank you to the New Zealand Trade and Enterprise and National Geothermal Association of the Philippines for the invitation to attend this meeting