Extracting lithium from geothermal brines and crushed ore requires a complex family of technologies and systems. If your facility has been exploring new ways to extract this valuable metal, you’re probably wondering, “How much does it cost to extract lithium from geothermal brine and crushed ore?”
Estimating the cost of a lithium separation and polishing system is complicated, in part due to the many factors and variables that play a key role in system design. This article describes what some factors affecting the cost of lithium extraction systems are and how they might apply to your facility’s processes.
What steps are included in a lithium extraction system?
Clarification and filtration
Each lithium extraction process has a unique polishing step that will depend on the product being manufactured (whether it’s lithium carbonate, lithium sulfate, or lithium hydroxide). These steps will also vary based on the type of feed stock being used, such as ore or liquid brine.
But, for the most part, after all the primary and crude removal of unwanted metals yields a brine that can be secondarily processed, clarification and filtration are typically the first steps of lithium processing to remove physical impurities from a lithium-saturated brine.
There are many ways to do this; however, using clarification followed by filtration is generally the preferred way to begin the lithium extraction process. It’s also common for companies to opt for the simplicity of lagoon settling before running their brines through high-end membrane filters next, and increasingly, these high-end filters are candle filters or membranes capable of removing unwanted particles down to less than one micron.
Ion exchange and brine softening
The second step to extracting lithium is typically an ion exchange process called brine softening to further remove calcium, magnesium, iron, and other unwanted metals from the brine solution. This technology is very similar to the technology used for brine filtration in the chlor-alkali industry with specialized chelating resins designed to pull metals out of brine solutions in a merry-go-round, three-vessel configuration.
Evaporation and high-pressure membranes
After these steps, the facility should be left with a solution that is highly concentrated with lithium (whether in the lithium carbonate, lithium hydroxide, or lithium chloride state). At this point, typically there is either an evaporation or high-pressure membrane step that takes the lithium to a higher concentration and, depending on the product being manufactured, this can even be a two-step process with high-pressure membranes first and evaporators second.
End-of-process polishing and posttreatment
Lastly, the brine will enter a polishing system where an electrochemical cell separates the lithium from the brine. From here, any required posttreatment options are done so according to the facility’s end-product goals.
The main factors of lithium extraction system cost
One of the main factors affecting the types of technologies required for your facility’s brine-extraction system includes the different types of rare metals and earths that are present. Certain metals and elements can require processing steps to be added, as extracting lithium can be complicated by certain metals, such as zinc or lead. If these are present in the stream, the facility might have to remove these impurities first, lithium second.
Other front-end contaminants, such as silica, sulfates, iron, calcium, magnesium, hardness, suspended solids, etc., can also make it more difficult to get the brine into a condition where it can be polished and used for the separation/concentration ends of the process. So, again, these will need to be removed prior to extracting and concentrating lithium.
Another big factor is the concentration of lithium in the stream. If lithium is not at a high enough concentration in the liquid stream, then the cost to concentrate it up increases the overall cost per kilo of lithium substantially. Sometimes this can be to the point where it doesn’t make it worthwhile to recover the lithium in the first place. The higher the concentration of lithium, the less amount of ore and brine processing your facility is required do, which also reduces secondary wastes and overall cost.
In general, the higher the flow rate of your lithium extraction and polishing systems, the bigger the equipment and the more the capital cost will be. Systems are also usually customized for lithium extraction because the applications are unique on every project.
Other important factors to consider when pricing the cost to extract lithium
- Up-front planning. Developing the concepts, designs, and regulatory requirements for your project is the first step to planning your lithium extraction system. The cost of engineering for this type of project can typically run 10–15% of the cost of the entire project and is usually phased in over the course of the project, with most of your investment being allocated to the facility’s general arrangement, mechanical, electrical, and civil design.
- Space requirements. When planning for a lithium extraction system, the size of your system will affect your cost, and the footprint is usually large, so keep in mind that sometimes your plant location can affect the cost of your system. For example, if your plant is located in a place that is very expensive when it comes to space, you might want to aim for a smaller footprint, if possible.
- Installation rates. Another thing to keep in mind is the installation rates in your area. These also fluctuate by location, so be sure you’re aware of the cost to install the system and factor this into your budget. In areas where installation costs are high you may want to consider prepackaged modules versus build-in-place facilities.
- Level of system automation needed. When it comes to the level of automation you need for your lithium extraction system, there are two options. The first is a higher level of automation where you won’t need an operator present for much of the time. With type of automation, you can eliminate much of the human error associated with running the plant, and although this option is more costly up front (an initial investment in more sophisticated PLC controls and instrumentation), the ongoing labor costs are less. The second option is a lower level of automation with less capital cost, but with added labor, this can end up costing you more in the long run. When deciding whether or not to invest in more costly controls, you need to consider what works for your company and staffing availabilities.
- Turnkey and prepackaged systems. If you are able to order your lithium extraction system prepackaged, this will typically save you about three months in construction time at about the same cost or less. A benefit to having your system prepackaged is that the production facilities and fabrication shops that assemble your system are, more often than not, highly knowledgeable about the type of system they are manufacturing. This results in a quick and efficient fabrication versus build-in-place facilities. Sometimes when you hire a field crew, there is a bit of a learning curve that can add extra time and/or cost to a project. SAMCO specializes in these types of turnkey, prepackaged systems, and for more information about what we offer, you can visit our website here. Installation costs will vary, but typically range between 15–40% of the project cost, depending on the specifics of prepackaging and amount of site civil work needed.
- Shipping the system to your plant. When having your lithium extraction system shipped to the plant, you usually want to factor in about 5–10% of the cost of the equipment for freight. This can vary widely depending upon the time of year you are purchasing your system in addition to where your plant is located in relation to the manufacturing facility. When you are looking to purchase your system, check with your manufacturer to see if there is a facility where the system can be constructed closer to you, if not on-site.
- Operation costs. Also keep in mind that particular technology packages cost a certain amount to purchase up front, but you need to also factor in system operating costs over time. For decisions like these, you need to weigh the pros and cons of initial versus long-term cost investment in addition to what works for your company and staff. You will likely want to look into having someone develop an operating cost analysis so your company can plan ahead for the operating cost over your lithium extraction plant’s life cycle. This might help you consider whether or not you want to spend more on your system initially or over time.
- Other possible costs and fees. When purchasing a lithium extraction system, you might also want to keep in mind what other hidden costs and fees might be. For example: Will there be any taxes on the system or additional purchasing fees? What are your possible utility costs to the installation area? Will there be any environmental regulatory fees and/or permits? Any ongoing analytical compliance testing you need to pay for?
Also consider that there will be costs to treating the secondary waste produced by the system. With stringent environmental regulations, you will need to either treat the waste for hauling away or solidify with a filter press/evaporator and transport to third party disposal firm.
Also, be sure to ask your system manufacturer about options that might be cheaper to install. They might be able to shed some light on the more installation-friendly systems with suggestions on how to keep your costs to a minimum.
The bottom line
For front-end filtration, plan spending anywhere from $750,000 to $2.5 million depending on the amount of filtration, flow rate, and automation on the filters. The brine IX system will be in the same range. Lower flow rates (around 50 GPM) would be in the range of about $300,000 to $400,000, and higher flow rates (500 to 1000 GPM) will be in the range of $1.5 to $3 million.
Membrane processes are very customizable, and a 50 GPM high-pressure membrane system to concentrate lithium may be in the $200,000-$400,000 range, a high-end 1000 GPM system will be in the $2 to $4 million range.
A complete operating pilot plant installed and running for a 1/10 scale can cost $50 million to $150,000 million. A large integrated facility can be as high as $500 million to $1 billion USD.
Can SAMCO help?
SAMCO Technologies has over 40 years’ experience in identifying appropriate brine and water treatment solutions to help lower costs and waste volumes while increasing lithium production yields. For more information or to get in touch, contact us here to set up a consultation with an engineer or request a quote. We can walk you through the steps for developing the proper solution and realistic cost for your lithium purification and separation needs.
To learn more about SAMCO’s innovative technologies that we commonly apply for lithium production facilities, visit our page on brine and lithium recovery, softening, and purification.