Lithium
By Richard D Walsh
WHAT with Northern Lithium’s well publicised test results, there’s been a lot of chat and questions about the production of lithium in our Dale.
I thought that folk might find it useful if I wrote about where I think we are at the moment.
“Why should Richard Walsh write” I hear you ask”. Well, let me set out my qualifications, I am a civil engineer of some thirty years’ experience. I admit I’ve no direct experience in lithium production, and can’t answer all the questions, (it’s pretty niche after all). But I have been involved in design and production of facilities for similar industrial processes – I’ve even worked with one of the partner companies I’ll be naming below.
Also, my degree is half geology, so I have some useful background there to offer the conversation. Just to nail my colours to the mast: whilst I have some concerns, I think that lithium production in Weardale is, overall, a Good Thing.
I think the first thing to say is that the activities in The Dale do not aim to produce pure lithium. The end product is lithium carbonate, for use in batteries. Whilst anything taken in huge quantities can be harmful, lithium carbonate is pretty benign: it even has (in a higher-grade form) medical applications, used, for example, in the treatment of mental illness such as bipolar disorders.
The second thing to say is that there are two companies wanting to extract lithium from Eastgate. Northern Lithium and Weardale Lithium. Their websites are: Weardale Lithium – Weardale Lithium
And Mineral Exploration and Development Company | Northern Lithium
It has to be said that the Weardale Lithium’s website is a bit more focused on selling their plans to the community, whereas the Northern Lithium’s website is more technical and focussed on investors.
Having said that, Northern Lithium have set up a fund for community projects in the Eastgate/Westgate areas. Unfortunately, the deadline for application passed at the end of May, but we can expect to hear who is benefitting in the near future.
It’s tempting to think there is a choice between the two companies. The truth is we might have one or the other (or both, or neither) of the companies working in Weardale, but this will be mostly decided by hard-nosed economics, technology and economics, and not the wishes of the good folk of The Dale.
Northern Lithium state that they have “up to 45 years’ exclusive development, appraisal and production rights covering mineral rights owned by the Church Commissioners for England across circa. 240 sq kms (60,000 acres), of the North Pennine Orefield.” I’m not sure where this agreement leaves Weardale Lithium.
The lithium itself is found in the Weardale Granite. The Weardale Granite is never on the earth’s surface. It occurs about 1km down under all Weardale (and beyond), but can only be extracted where the granite is fractured, for example were the Slitt Wood Mineral Vein cuts into it. So there is not that many places – other than Eastgate – where the material can be extracted.
The other thing that’s worth mentioning is that there’s a bed of very hard, waterproof rock (The Great Whin Sill) about 150-200m down from the surface at Eastgate that acts as a seal between our useful water table and the fluid in the granite.
Both companies suggest a similar thing. They would extract brine from The Weardale Granite/Slitt Wood Mineral Vein, remove the lithium carbonate, and then return the brine to the ground. I confess I don’t know the detail of the extraction process: I think of it as a “black box” – you put things into the black box (brine from the granite, electricity, perhaps some dosing chemicals), and you get stuff out (lithium carbonate solution, water that can be returned to the deep boreholes, water that can be discharged to the river, waste products that have to be taken off site).
I’ll detail below my understanding of what goes on in the “black box”, but to be truthful I don’t see that as being as important as what we need to put in, what comes out and, I suppose, what the “black box” looks like.
I immediately have questions of both companies:
- Are you going to discharge water to the Wear, and how will you guarantee it’s purity,
- Does the process require dosing chemicals, how much, what form (liquid, powder, granules), and how do they get to your plant,
- How much lithium carbonate solution will be produced, what form, and how will it be removed from site,
- What other waste products will be produced, in what form, and how will they be removed from site.
The big underlying questions here are “how many wagon movements do you expect when the plant is fully operational?” and “how much of a disaster is it if one of your vehicles leaks or catastrophically crashes.”
I’m less concerned about electricity consumption. Weardale Lithium’s proposal appears to include solar panels, and both companies propose using the warm brine as an energy source, in addition to the large electric substation on site
I’m also not unduly concerned about re-circulating the brine into the ground. Both companies propose returning the brine to the ground a long way below the waterproof Great Whin Sill, so the fluid cannot enter our useful water table – although I have a minor concern over the integrity of the borehole casing, especially as it gets older.
Whilst the companies have both proved by testing that their processes work, the two “black boxes” utilise very different technologies. Weardale Lithium have partnered with a company from Houston, USA, called KBR, who offer a system that doses the brine with an active material that selectively captures the lithium; it seems to me to be a chemically-induced crystallisation and then evaporation process.
Northern Lithium, in contrast, have partnered with a Widnes (UK) company called Evove, who use a nanofiltration membrane rather than the absorption technique that KBR use. Evove have further partnered with a local company, Ross Shire Engineering for the pilot plant, and I assume that RSE will have a continued involvement. All of these companies have good, albeit technology-heavy websites:
KBR Lithium – Technology – Critical Minerals
Evove Direct Lithium Extraction process | Evove DLE
Ross Shire Engineering Trusted Water Technology Solutions – RSE
Again, to nail my colours to the mast, I’ve worked with RSE, and found them very professional
Weardale Lithium propose using the two existing boreholes sunk in 2004 & 2010, near to the back road. They propose small scale buildings, designed to match the local architecture, to house power supplies and pipework at each borehole head.
Brine will be pumped from borehole 1, through fields and along the road in an insulated pipe of 150mm (6”) internal diameter, and will use the existing gantry to cross the river to the redundant Eastgate Cement works. Here they propose their main processing plant, where lithium carbonate will be extracted from the brine. A second pipe, largely running in the same trench as the first, will return brine to borehole 2. As noted above, the Whin Sill ensures that the brine cannot contaminate our groundwater. Weardale Lithium have appointed an architect, Group Ginger, to design their buildings, and their visualisation and design rational can be found here:
Weardale Lithium – Group Ginger
It has to be said that the visualisation on Group Ginger’s Website is rather different to the one on Weardale Lithium’s website: the Weardale Lithium visualisation has a far more industrial feel. They have also appointed Arup to carry out the civil and structural design, including, I think, the necessary strengthening of the existing gantry over the river.
Weardale Lithium have planning permission for this scheme. The use of the existing gantry over the river means that the wagons going to and from the process will be entirely on the main road, but I suspect that during the pipelaying activities the back road might have to be temporarily closed.
They suggest that the site will employ between 20 and 50 people, and they have an agreement with Tees Valley Lithium to further refine the product before onward transportation to the Envision AESC Gigafactry in Sunderland.
It is interesting to note that Weardale Lithium’s technological partner, KBR, talk about their process being used to recover lithium from batteries. I don’t know if Weardale Lithium intend expanding in this direction, thus ensuring the longevity of their plant.
Northern Lithium’s plans are less clear. My understanding is that they have sunk two new boreholes to the South of the river, and that the plant will be sited between them. It is not clear how bulk materials will be transported to and from the plant – it’s at the other side of the river to the main road. I have not seen any architectural visualisations or drawings of the proposals, nor can I find details of their proposed permanent facility on the Durham County Council Planning Portal (I can only see their proposals for their successful pilot plant). My expectation is that it will have a fairly “industrial” appearance, albeit with a much smaller footprint than Weardale Lithium’s proposal – it might even be fully containerised. They do not comment on either the number of local jobs they predict, nor their intended customers.
Whilst acknowledging the local contribution to good causes that has been made by Northern Lithium, it would be nice to see either or both companies investing in training our young people, so that the innovative skills need to develop mineral extraction in The Dale are available locally.
My big concern is the medium-term future. We have two companies competing over the same resource and the same marketplace (and I’ve heard it said that the market may not grow as quickly as anticipated as we get better at recycling): in my experience, when economic pressure increases, the first things to slip are environmental, health and safety issues, and who knows what resource will be available to the HSE and Environment Agency to monitor such things in a few years time?
And the final concern. What happens when the lithium runs out? I would appreciate both companies’ comment on how they intend decommissioning the works, and reinstating the Dale’s natural beauty when the process ends.
