Geo40™ Limited is the first company to commercialise, in large scale, the extraction of silica from geothermal fluids. Here’s how —
Geothermal electricity: Geothermal electricity is a proven, mature technology
Geothermal energy originates from deep within the earth’s crust in geological terrains that have experienced relatively recent magmatic and volcanic activity. Generally high-temperature geothermal fields are located at tectonic plate boundaries where either one plate is being forced over/under another (Pacific Ring of Fire) or where two plates are drifting apart and the geothermal gradient is much higher (Africa Rift System). In both of these cases, the crust of the earth is thinner than normal and often more fractured. This allows for the earth’s heat to superheat ground water forming geothermal fields. Deep wells (1-5 kilometres) are drilled to access these heated fluids which are in turn used to generate electricity before being reinjected back into the ground (see Figure).
Geothermal electricity is a mature technology with New Zealand being recognised as a global leader and one of the first countries to develop steam-flash plants in the 1950’s. The heated fluids are extracted at high temperature (often 200-300 degrees C) and high pressures. Within the electricity plant the heat and pressure is used to turn turbines that generate electricity. Geothermal electricity is used as base-load as it provides high availability (95%+) and low operating costs once the setup costs have been incurred. Several global companies provide geothermal power stations including Ormat, Toshiba, Fuji and Mitsubishi.
Technology: Geo40 extracts silica from geothermal fluids
Geo40 has developed process technology for the removal of silica from geothermal fluids that have already been used for power generation. This technology comprises two main sub-systems: extraction and processing.
The extraction plant is located adjacent to the geothermal power plant and extracts silica from the reinjection fluids. The extracted silica is concentrated in solution to a 10% weight concentration. The fluids, now less the silica, are reinjected into the underground reservoir through the existing reinjection wells or can be used to extract further minerals and generate further electricity prior to reinjection. This silica concentrate is then transported to a central processing site for further processing and value add.
At the processing site, the silica colloids are grown to a range of colloid sizes between 8nm and 16nm in diameter and the concentration of the silica is increased to 30-40% by weight. Product is shipped directly from the processing plant to the customer (distributor) site.
The IP landscape in this area is uncluttered and relatively open. Geo40 has filed three wide-reaching provisional patents covering all developments over the last five years. In addition, there are numerous trade secrets that will be retained by keeping elements of the manufacturing process in-house. The Geo40 IP platform is considered to be broad and very robust.
Learn How We Harvest Silica Sustainably at Geo40
Find Out More
Proposed business model: Value captured from generators and silica distributors
Geo40 has commercial relationships with two groups: (1) geothermal electricity generators and (2) silica distributors.
Geothermal electricity generators: Geo40 has begun installing proprietary extraction plants, fabricated by or for Geo40, on site at geothermal electricity plants. The number of extraction plants depends on available fluids. The extraction plant will be designed in modular form with each unit able to process 5,000tpd of geothermal fluid. Geo40 will own and operate the extraction plant and equipment and charge the generator a small fee for the extraction of the silica. The fee will include any payments to governments for minerals extraction rights. There are no government royalties’ payable in New Zealand.
Silica distributors: Colloidal Silica is generally used as a component with other speciality chemicals, to support a process or product being produced. For example, colloidal silica and other mineral flours and sands are sold into precision investment casting market and used together to make moulds. Specialty chemicals companies will often aggregate these products from multiple manufacturing sources and sell the bundled products to end users. Geo40 and Iwatani have signed a Memorandum of Understanding for distribution of Geo40 colloidal silica in Japan and other Asian countries. Geo40 is working with other potential distributors for selected geographies and markets.
The Sales Team: A sales team is responsible for managing Sales and Service of colloidal silica to an expected small number (<5) of regional distributors plus direct sales into Australia and New Zealand. This team is based in New Zealand and USA and service the key markets of Asia Pacific and North America.
The Business Development Team: A business development team provides ongoing business development by working with existing generators globally to identify, size and close the silica extraction plant opportunity for each generation site. This team also work on the establishment of centralised, further processing facilities and establishment of relationships with local distributors.
Meet the Team
As part of Geo40’s ongoing research and development other specialty silica products are in development. To date specialised silica gels have been developed in the laboratory for customer trials. During 2019 further work will be completed targeting a range of specialised silica solids products.
Geothermal fluids are rich in other minerals, however, to access these minerals efficiently the silica needs to first be removed. Geo40 has begun work on the extraction of lithium and boron. Pilot plant trials for the extraction of lithium began in 2017, boron in 2018 and will continue during 2019.