I agree the title is misleading, but in both directions. The 40% number is just for Marcellus shale gas wells - that is, basically shale from primarily a single state (Pennsylvania).
Also, I would think that the fact that it just comes from shale gas well wastewater means it would be more commercially viable to actually extract.
Since this is high up, I'd like to point out some comments made down thread that cite the paper disagreeing: the Marcellus well water isn't very economically friendly at all. For many, the composition is off (e.g. too much mercury) and for most, they produce most of their water for the first two years of operation.
If everyone on earth took a high dose of lithium carbonate of 1000mg a day, that would be 7000 tonnes a day. It's 14/74 lithium by weight, so around 1300 tonnes of lithium metal per day. Total lithium mine extraction is 180,000 tonnes a year, so 500 tonnes a day.
So assuming everyone on earth was fully dosed up, and you could collect all the waste, it's actually a lot!
The actual figure of 2 million people in the US on lithium carbonate, probably on smaller doses, is much less interesting: under 2000kg of pills, "only" a few hundred kilos of pure lithium per day. Though I think still interesting scale illustration that one pill each for 0.5% of people in the country weighs about the same as a car.
At least in the US, 40% of wastewater solids are already used for agriculture [1]. Another 10% is used for landscaping. The same site estimates that if all US biosolids were applied to agriculture, they would supply 3.2% of applied phosphorus.
You can buy wastewater solids down at the garden store, under the longstanding brand name Milorganite. It's a good lawn fertilizer (6-2-0) if you don't need potassium, which I assume just washes through the waste treatment system. It's also high in iron, which is desirable for deep green grass and moss suppression. And the label says it can be used on vegetables, so there's nothing notably toxic in it.
The primary concern with waste solids would be the presence of heavy metals, I think, but those shouldn't be getting into the waste water stream anyway. Heavy metals are a concern anyway in phosphate fertilizer; many deposits of phosphorites have troublesome amounts of cadmium.
I would have thought biological contamination was an issue. I, perhaps foolishly, presumed wastewater treatment plants would be fairly good at removing heavy metals.
Biological contamination seemed like a bigger issue to me since the solids could be re-colonized post-processing.
Maybe this is a more processed product than I’m thinking of. Surely their not selling literal bags of poop, maybe it no longer resembles human feces enough for bacteria?
It's the stuff that's left after anaerobic, then aerobic, bacteria have chowed down on the sewage. It's basically dead bacteria. Any pathogens would have become food for these decomposers.
I think I'd also worry about residual drugs. Some don't break down quickly.
Maybe we should rethink wastewater streams for selective recycling: stormwater, graywater, blackwater, and yellowwater. Perhaps the latter two should be recycled where possible and then residual wastes close-loop incinerated to prevent leeching any sort of biologically-active molecules or pathogens into the environment.
The quantity of drugs in the waste stream is surprising. For example: I take 1000 mg daily of metformin. Although I have (of course) never measured it, a person produces 100 to 250 g/day of fecal matter. This is 75% water, so reasonably my excreta, on a dry basis, is up to 4% metformin(!). Metformin is largely excreted and breaks down in the environment only slowly, so it would contribute significantly to the nitrogen figure for waste-derived fertilizer.
Wikipedia says this:
"Metformin and its major transformation product guanylurea are present in wastewater treatment plant effluents and regularly detected in surface waters. Guanylurea concentrations above 200 μg/L have been measured in the German river Erpe, which are amongst the highest reported for pharmaceutical transformation products in aquatic environments."
Lithium is everywhere, mostly in lowish concentrations but there's a lot of it. Way more than we'll ever need. The trick is extracting it economically.
It comes in several forms. Brines and mineral deposits. Brines are a form of very salty water that form when most of the water evaporates. Chile conveniently has some salt planes where that has happened naturally. The dead sea is very rich in lithium too. The salt lakes in Utah have plenty of lithium. And apparently Cornwall has some underground brines that have high concentrations of lithium. And actually our oceans are full of lithium too; albeit in lowish concentrations. The reason it's in water everywhere is because it leaches out from the earth crust. Those Cornish brines are the result of underground water being heated up geothermally and extracting lithium from granite.
Extracting lithium from brines or sea water can be done through evaporation or through filtering. There are some companies experimenting with filtering using nano technology. The advantage is that it is less energy intensive and you need way less clean water. And you can extract all sorts of stuff from these brines as they contain more than just lithium.
Mineral deposits in clays and rocks are also fairly common. There are viable lithium mines in many countries. Most of these are not being exploited because demand for lithium wasn't that high until only a few years ago. Also, it used to be a relatively worthless waste material that you'd have to separate from copper in copper mining and that would then get dumped. It's only fairly recently that lithium became valuable enough to bother to extract it.
And of course there's a rapidly growing third source of lithium that's very convenient to extract because it occurs in super high concentrations: all the products we make that have lithium in them. Like batteries. The lithium isn't actually consumed or lost when these products reach their end of life. Lithium recycling is becoming a big industry. Right now the demand for lithium is still growing rapidly so only a fraction of the demand can be met through recycling. But in a few decades that should taper off. At that point most of our lithium needs could come from recycling.
There's no shortage of lithium and there never will be. There are temporary dynamics where bringing new lithium production online simply takes time and money which is why prices were high a few years ago and are trending down lately. Actually, Bloomberg NEF recently published a report where they note that it seems we are heading for significant over production of lithium batteries. So, they are predicting price jobs and cancellations for a lot of the already committed investments on that front. https://about.bnef.com/blog/china-already-makes-as-many-batt...
On the plus side, the rapid decrease in LFP cell prices is fueling a massive grid-connected storage boom, and will also drive global BEV adoption with those cheap Chinese cars that Biden just slapped a huge tariff on. Sad we won't see those, but good that global oil demand is being undermined at an ever increasing rate.
There's something utterly fascinating about watching a long talked about technology suddenly hit the liftoff point and explode into the markets.
> Already, researchers in the lab can extract lithium from water with more than 90% efficiency
Maybe that's step one, but of course the real question is whether it can be accessed economically. The paper mostly doesn't discuss economics, and indeed the only reason the research appears to have been done is because there is a regulatory requirement to have the wastewater analyzed (as opposed to, e.g., being done because the company thinks it's possibly economically valuable).
Here's the abstract of the research article:
> Decarbonatization initiatives have rapidly increased the demand for lithium. This study uses public waste compliance reports and Monte Carlo approaches to estimate total lithium mass yields from produced water (PW) sourced from the Marcellus Shale in Pennsylvania (PA). Statewide, Marcellus Shale PW has substantial extractable lithium, however, concentrations, production volumes and extraction efficiencies vary between the northeast and southwest operating zones. Annual estimates suggest statewide lithium mass yields of approximately 1160 (95% CI 1140–1180) metric tons (mt) per year. Production decline curve analysis on PW volumes reveal cumulative volumetric disparities between the northeast (median = 2.89 X 107 L/10-year) and southwest (median = 5.56 × 107 L/10-year) regions of the state, influencing lithium yield estimates of individual wells in southwest [2.90 (95% CI 2.80–2.99) mt/10-year] and northeast [1.96 (CI 1.86–2.07) mt/10-year] PA. Moreover, Mg/Li mass ratios vary regionally, where NE PA are low Mg/Li fluids, having a median Mg/Li mass ratio of 5.39 (IQR, 2.66–7.26) and SW PA PW is higher with a median Mg/Li mass ratio of 17.8 (IQR, 14.3–20.7). These estimates indicate substantial lithium yields from Marcellus PW, though regional variability in chemistry and production may impact recovery efficiencies.
> Further, extraction of Li from [wastewater] with high Mg/Li mass ratios (> 6), such as in [southwest Pennsylvania], is less efficient and expensive relative to low Mg/Li extraction methods31. The low Mg/Li composition of [northeast Pennsylvania] produced waters are comparable to salar brines, such as the Atacama brines of Chile, which are favorable to more economical and sustainable evaporative and distillation Li recovery methods. As a result, the higher Li yields from [southwest Pennsylvania] wells may be more costly to extract due to the lower concentrations and reduced treatment efficiencies due to the high Mg/Li nature of these waters.
Also
> Another important consideration in the total Li yield of a reservoir is the well production decline rate. A typical Marcellus well has an 80% decline in production of water within it’s the first 2 years (SI 4.). Sustainable production of Li at volumes reported in this manuscript require continuous addition of new Marcellus wells to supplant older, less productive wells.
Shares in Core Lithium have crashed by more than 20 per cent this morning after the company announced it was reviewing its operations near Darwin because of "the deterioration in lithium market conditions".
Anticipated demand drove the opening of known prospects, uptake slower than expected has seen the boosted price fall and the fresh mines shuttered again.
