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Cape Town

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In principle, yes. But it's probably not economically viable. Rare earth oxide prices are in the range of 10-100 USD per kilo. Platinum and gold go for ~1000 USD per ounce. Of course the tailings grades will be different but as far as I know these are the only metals which have gone through significant tailings reprocessing efforts. In SA that's also mainly because they had loads of material that had been mined 100 years ago when recovery was lower. I think copper might also reprocessed in a few places but I would guess only via heap leaching (stick in some plumbing and irrigate your dump with acid).

Interesting. I have a few thoughts.

Rare earth elements are currently sourced essentially from two distinct mineralogies: hard rock mining from igneous intrusions with the rare earths contained in e.g. bastnaesite and monazite (such as Bayan Obo in Inner Mongolia and Mountain Pass in California), and from ion absorption clays (for reasons above my pay grade these only occur in the subtropical belts hence their prevalence in southern China).

These two ores have some important distinguishing characteristics. Firstly, the hard rock ores tend to be enriched in the so-called "light" REEs (e.g. lanthanum, cerium) whereas the clays are somewhat enriched in the "heavy" REEs (e.g. lutetium, yttrium). They also have very different processing methods. Hard rock ores are processed in a more conventional way, via grinding/milling the ore, floating the valuables and then sequentially removing elements using solvent extraction. With maybe leaching in there somewhere... This is more or less similar to processing for the precious metals but as I understand it the large number and chemical similarity of the REEs makes this more resource intensive. On the other hand, in the clay ores the REEs are already in the free ionic form and are flushed out via ion exchange in heaps or vats.

Both of these processing methods are pretty nasty but one falls under the remit of large state-controlled enterprise and the other can be done by a dude with a spade and a vat full of salt water. So it's no surprise that there is a large unregulated industry around the processing of these clays, which is in turn responsible for some seriously hellish mining landscapes and environmental degradation. The Chinese government is apparently cracking down on that sort of thing which I can only imagine involves a lot of authoritarian police state tactics.

Coming back to the article, I wasn't entirely sure at what part of the above processes this advancement would fit in. The paper they are referecing seems to have used spent ceria polishing powder and lutetium crystal waste as the feedstock for their experiments (i.e. already very pure in terms of REE content). So it appears that this applies to the extraction phase - they first had to go through an alkaline roast and HCl dissolution before using the new solvent. This doesn't really enable making a big difference to the overall production process. In the conventional mining case, it will still need to produce masses of somewhat radioactive tailings, require massive amounts of energy to grind the ore and so on. Similar situation for the clay mining. It's an unfortunate reality that the amount of value added in a processing step tends to be inversely proportional to the environmental impact associated, and this technology seems to be acting on the end of the pipe.

DWol  ·  link  ·  parent  ·  post: Bitch Session #1: Technology Lows

This might be something that can help you? I.e. installing the apk directly and sidestepping Google Play which is what I assume is in your way...

DWol  ·  link  ·  parent  ·  post: Pubski: July 25, 2018

Hey, just a quick one as I'm on my phone: this is probably mad overkill but I can't help thinking that this is a good use case for many of the techniques mining exploration people use for mapping geological features (exploration geophysics).

It's not my personal focus but I think you'd have a good chance of finding the pipe using ground-penetrating radar or electrical resistance tomography (where I live the domestic sewer pipes are plastic but maybe you might have luck with a metal detector too). Some guys that I work with spent some time trying to use these to do realtime crevasse detection and I believe it's the same technique used for archaeological surveys. Whether it's a commercially available service with a reasonable price tag I'm not so sure.

Anyway as I said it's probably overkill but it immediately popped into my head so I thought I'd share. Cheers.

    I think it speaks volumes that even a group of people with a single goal in mind and the best of intentions in their hearts have to struggle in such a way. I think it speaks volumes as to why sometimes society seems really messed up.

Don't really think I have much insightful to say, but this thought up here is important. The question I am left asking is whether we are doomed to this? Will things get better in my lifetime? I heard someone say once that as a first pass estimate, it takes about as long for conflict to be resolved as the conflict had been going on in the first place. In SA that means we are only about 10% of the way there, according to the consensus for when the shit hit the fan.

I think the Arch is right in saying there's no future without forgiveness, but these days one has to wonder whether forgiveness has any value if it was given for free. 24 years is sadly enough time for us to collectively begin to forget the past, with the result being that no-one really knows what they gave away or gained anymore. It's a bad place to be because it means that now we can't even agree that we "have the same goal in mind". The irreversibility of that lost opportunity is honestly the saddest part for me.

DWol  ·  link  ·  parent  ·  post: Pubski: February 14, 2018


So Msholozi has stepped down. TBH I am somewhat surprised. Most of his speech was about being beholden to only the constitution (as opposed to the resolutions of his party). And then in almost no time at all, finished it off with a "that being said".

As the president-in-the-wings finds it sufficient to enrich himself through only vanilla capitalist exploitation, the global investment crew seem to think this is a positive development. As to whether that is true on any more fundamental level remains to be seen.

But tomorrow the sun will come up and there will not be any military on the streets and people will be as free as they were today and there are reasons to be happy. Happy Valentine's day!

DWol  ·  link  ·  parent  ·  post: Pubski: February 14, 2018

Hey all. Four beers down.

His Excellency, the president of the Republic is busy addressing the proles in re his feelings about resigning.

For all its faults, I am grateful that in SA whether the big man feels like doing so or not is largely irrelevant. A motion of no confidence will occur tomorrow and, with the support of his own party, remove his ass.

But I can't type fast enough to keep up with the speech so hold tight for some retrospective analysis.

DWol  ·  link  ·  parent  ·  post: Pubski: January 24, 2018

Bittersweet start to the year.

On a “career” level, things could hardly be better. I finished up the article write-up of my work last year and sent it forward for my higher-ups to check out. It was the definitive box to tick that would signify the end of 2017 and the beginning of 2018 – which also means that I am now officially starting my PhD. First order of business: proposal.

Also in the pipeline is a trip to Vancouver to present my work at a fancy conference, as well as the opportunity to head to Portugal and Finland for my case studies and sampling.

Unfortunately, life comes at you hard – my supervisor was diagnosed with cancer early last year and just learnt that it has spread all over. Terminal, with a horizon of end April. I’m finding that it’s a really strange thing to process. Time will tell. But I do know that I have a massive fire in the belly to get my proposal done such that I can present it with her there – just on a personal level it feels important.

Tough months ahead…



Wow. Thanks. This article hit me hard. It meanders through thoughts I have had for a while now and although I don’t think I have really formed a fully-fledged opinion, I think it touches on a number of difficult yet important conversations.

In South Africa, segregation is like a corporeal thing: I don’t really have the words but I want to convey that it is something very tangible which permeates basically every part of life.

Here is where I grew up:

Here is where I live now:

Here is a random town in the middle of nowhere:

Basically every town in the country has the same scars.

There are some important things to note from these (particularly the Cape Town one) which I think are broadly similar to the American experience – spatial integration left to its own devices takes place in two ways: upward mobility of PoC, and gentrification of a few well-located areas. Note that it does not appear to occur through downwardly mobile whites (or even idealistic ones) moving into the townships. These dynamics are important because they reflect an imbalance which gives segregation a kind of self-sustaining momentum.

Schools are an obvious site of friction for this sort of thing – the place where a child’s future is supposedly shaped. And so the author hits on an important question when she considers where to send her kid: contributing to (racial) diversity in an affluent white school or contributing to (class?) diversity in a poor non-white school.

The first aligns with the upward mobility idea above and the second with the idealism situation. The comparison is not absolute but suffice to say in both cases there is an anabatic and a katabatic option. One appears to be rational, the other based on ideology:

    One family, or even a few families, cannot transform a segregated school, but if none of us were willing to go into them, nothing would change.

    The few segregated, high-poverty schools we hold up as exceptions are almost always headed by a singular principal like Roberta Davenport. But relying on one dynamic leader is a precarious means of ensuring a quality education.

This is of course the crux of the reasoning for that second option. I think on face value it’s a laudable idea. It’s certainly an important question in general: what if any active role should be played in the integrative “project” by those with choice, resources, social capital etc? (Imbedded in there is the equally quagmired issue of paternalism but I don’t want to go there)

    But integration as a constitutional mandate, as justice for black and Latino children, as a moral righting of past wrongs, is no longer our country’s stated goal.

I agree here that this is troubling – as I said, integration left to progress organically has, I think, undesirable outcomes. At the least we can agree that it happens slowly.

    In early spring 2015, the city’s Department of Education sent out notices telling 50 families that had applied to kindergarten at P.S. 8 that their children would be placed on the waiting list and instead guaranteed admission to P.S. 307. Distraught parents dashed off letters to school administrators and to their elected officials.

FWIW we get a lot of this sort of thing in SA too but it’s more often under the bracket of language (an added spanner in the works).

The author's description of what happens along the whole redistricting thing is reminiscent of the arguments around gentrification – what seems a positive change on the one axis might have unintended negative consequences on another. What I got from this story is another example of the deep web of complexity which I think is ultimately the reason why this segregation thing is so hard to beat.

    True integration, true equality, requires a surrendering of advantage…

She gives this as a statement but I think it is probably the real site of debate on these sorts of issues – a debate which doesn’t look like being resolved any time soon.

DWol  ·  link  ·  parent  ·  post: Cape Town runs out of water on April 22.

Perhaps. It will depend so much on the implementation. Keep in mind that about a fifth of the city already receives their water through communal taps which is essentially what will happen for everyone. I also think the fact that it has been approaching so slowly means it will be more... orderly - at least in contrast to other disaster scenarios where everything happens at once and authorities are left scrambling. I can only speak for myself but I have made peace with having to queue for water and I guess most others people have too.

DWol  ·  link  ·  parent  ·  post: Cape Town runs out of water on April 22.

Indeed. I think there some interesting things to talk about here:

    Unless residents drastically cut down on daily use, warns Cape Town Mayor Patricia De Lille, taps in the seaside metropolis of four million will soon run dry.

I don’t know what “drastic” means in this context. Current metro usage is hovering fairly stable at 600 ML/day (consulting the oracle). Before people gave a shit, it would have been around double that. I can assure you that the lifestyle change I am currently undergoing certainly feels drastically in line with the apparent halving of usage.

Here is a nice visualisation of the projection that (reading between the lines) the City is using to calculate Day Zero. Messing with the values and replacing 600 with the target 500 (which appears to be as low as it wants to go) only buys a week at this stage. So really, any additional consumption changes don’t affect the ultimate situation – that it is going to come down to the wire and mostly up to the will of the gods. If it rains early and abundantly, the City buys time to introduce additional abstraction and concoct new bylaws. If not… I’ll see you guys on the other side.

For me the most interesting stuff is in the hard lessons being learnt – this situation will probably be the poster child for how long-term dynamics can take you for a ride. This article is a good explainer for those with little background. The key for me is this set of graphs:

The yellow dots indicate predicted years with 2017 (i.e. drought) rainfall. None of the models necessarily agree in the absolute sense but what they do show is that a little lower average and a little more variation is all it takes to turn what used to be a 1-in-1000 year event into a 1-in-50 year event. And that’s what the face of climate change is likely to be (even if it’s not the culprit here – I understand the jury is still out on that).

On the politics side, there are also unforeseen consequences. One of the biggest issues is that in SA, water is used as a cross-subsidiser in municipal budgets. So the reduction in consumption has had a big impact on the balance sheet. Furthermore, as the rich take themselves off the grid with rainwater collection and boreholes, this income will probably stay lower than before. On top of this, unregulated groundwater abstraction is likely to be lead to massive problems in the future.

    The local version of Craigslist is already full of listings for companies willing to truck in tankers full of water from less drought-prone parts of the country, for a price.

Along similar lines, I seriously worry about the potential impacts of a laissez-faire approach which allows this kind of thing uncritically. SA is dry in general, and the Western Cape is not the only province with issues. People are playing themselves if they think exporting their water footprint elsewhere in the country is a sustainable solution.

    According to city statistics, only 54% of residents are hitting their target, one of the reasons why Day Zero was moved forward a week earlier this year.

I am very sceptical of this number. I live in an apartment complex and like most in the City, it does not have unit-by-unit water meters – I suspect the 54% value refers to the ones they can be sure about and 46% includes both guzzlers and unknowns. In any case, again, this is one of the things which will likely change going forward. There’s a silly saying that you can’t manage what you don’t measure but I think it rings true in this case.

DWol  ·  link  ·  parent  ·  post: Dispatches from the shithole of Nambia

    I feel an apathetic slumber accompany even the scantest attention to the deluge of scandal, rank idiocy, and bigotry that comes daily out of our nation's capital.

Two related points:

The first is that I am starting to get the impression that the true equilibrium state of democracy is people fighting their elected officials and the officials simultaneously seeing how big of a cake slice they can get away with. Different countries lie in different places along the graft scale in this context. In such a situation, apathy is (at the least) dangerous - it allows people the opportunity to push the envelope a little more the next time.

But how do you react with anything but apathy for something which is so antithetical to what you believe in? The recent thread about Sam Altman's post got me thinking about this thing of debates and arguments - convincing other people, in whatever context, that you are right. When so much of the nonsense above is driven by what can lightly be described as a "difference of opinion". Do we entrust this kind of debate to our legislative bodies alone? What, really, is the process by which large amounts of people change their opinions?

I think if you truly believe something must be changed, or are otherwise unhappy with the state of affairs, you should try and actively foster that kind of change in opinion in others. People may hold opinions that are nasty (or even illegal) but this hopefully does not condemn them to those opinions. As I say though, I have no idea what a concrete strategy for this is because as sure as you are of your convictions, so sure are the others. Difficult.

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