RNU (ASX) General Discussions

Originally posted by Scarpa: ↑

I understand what you are seeking to do but IMO IMO it is not as simple as that - this post provides the basis of the estimates below and the methodology itself I am using to gauge expansion scenarios and what needs to be done (including the links) - Post #:53209913

1. Key comments from above embedded post when looking at the sample done for testing but relevant to estimates been Post #:53209913 :

i.)1kg per kWh of graphite is in the anode of batteries, and of this 50% is spherical graphite and 50% is synthetic graphite

ii.)2kg to 3kg of graphite flake concentrate (94%) is required for each 1 kWh.

iii.) Therefore you need 2 - 3 tonnes of concentrate to produce 1 tonne of spherical graphite

iv.)The key graphite product type for naturally occurring graphite is flake, which is what most producers use to produce a 94% (carbon) graphite concentrate.So I'll take the following 2 statements from the November 2019 feasibility study, where that feasibility study was in effect about producing 94% - 96% TGC. Noting recovery estimated at 91%.

2. Grade and concentrate

From 2019 DFS which can also guide discussion - DFS here - Post #:41348587

i.) At 10.7% input grade for feedstock, you need 10.31 tonnes ore to produce 1 tonne 94% -96% C concentrate (i.e. 825,000/80,000): refer page 4 - of the historical 2019 .
ii.) At 9.1% input feed need 11.46 orefeed to produce 1 tonne 94/96% concentrate (i.e 1650000/144000)

ii.) This implies at 7.4% LOM feedstock need 14.1 - 14.9 tonnes feedstock (i.e 10.7/7.4 * 10.31. Or 9.1/7.4 * 11.46). Will use 14.5 in my conversions below been mid point.

3. Mesh size

Not all the resource can be used for producing spherical graphite. I wouldn't solely focus on the below JORC table.

When we talk of Measured and Indicated resources that is more around the concept of geological confidence before you run your technical and economic parameters to determine how much of this is feasible to be economic, as per pic below.

The key with Measured and Indicated is about then running economic and technical parameters to get to your proven and probable reserves which are the basis for producing concentrate and from there spherical graphite. This post is probably ok for those who want to further understand how mesh size and flake is a key to producing concentrate and from their spherical graphite, and its importance etc - Post #:51768438If we return back to the 2019 DFS this is the key table:

You can see the probable and proven reserves are 82% of the Measured and Indicated category at that stage. Obviously proving up the Inferred resource is a key to further resource upgrades that can find its way to this Measured and Indicated category and then to Proven/Probable, as well as further exploration work by the way. At 7.9% C need roughly 13.6 tonnes feedstock to produce 1 tonne concentrate (7.9%/7.4% *14.5 tonnes)

We know in one of the latest presentations there was an upgrade in the tables as well:

Albeit grade in the proven/probable category reduced to 7.4%. Certainly see that further work they have done has improved movement from resources to the prove/probable category to about 92%

Conclusion
a.) Stage 1 - currently Stage 1 is for 28,000 tpa spherical graphite per annum for 40 years. This makes total spherical graphite production 1,120,000 for that 40 years.

b.) So to produce 28,000 tpa spherical graphite requires concentrate of 56,000 - 84,000 tpa 94% - 96% TGC. (Note - it takes 2 to 3 tonnes of concentrate to produce 1 tonne spherical.

c.) Moving to feedstock ore this means you need 812,000 to 1,218,000 tonnes of feedstock per year to meet concentrate need (multiply b above by 14.5 tonnes feedstock). The conversion rate a key

d.) So orefeed used to meet the 28,000 tpa spherical graphite for 40 year target becomes in total 32.5 million tonnes to 48.7 million tonnes depending on conversions. Obviously depending on the conversion rate of concentrate to spherical we have sufficient reserves to meet 28,000 tpa and some left over to increase Stage 1 production by about up to 60%, if the conversion rate is 2 tonnes concentrate to 1 tonne spherical - i.e you have 19 mt orefeed left over in the proven and probable reserve category at conversion of 2, and this can generate an additional 16,400 tpa spherical graphite (i.e. 19mt/32.5 mt *28000 tpa and then this figure divided 28000).

e. Point d above is much much much less increase if conversion is 3 tonnes concentrate to 1 tonne spherical graphite.

f.) Given the above estimates already include recovery rates as per the conversions themselves I did as working from DFS albeit an old one, Stage 1 expansions IMO need to prove up further resources if seeking to double Stage 1 production. The key to this is more exploration work and moving Inferred resources to the Measured and Indicated category and subsequent Proven and Probable Reserve category. It would be nice to get more resources in the proven reserve category too.

A very long winded VB induced post, but hope it helps, but used to exercise the cavity in the head. Anyway, hopefully helps debate and totally happy for someone to say this post is a load of crap too. Debate is fine, but that is how I am thinking anyway. Will post again when I have something else to add etc etc, but back to the weekend.

All IMO IMO IMO

Expand

Yet again some great points. I have to admit I had consumed a few VB's myself at the time of posting so I did make some oversights. Thanks for clearing up some of those issues. I feel like I learn something every time you post.

Firstly I made a mistake when I said ore and actually meant contained tonnes when I was referring to RNU's resource.

Also, on closer inspection of company announcements, it seems like the 105 k tonne figure is what's needed to produce the 28,000 k tonnes of PSG, so quite rightly a lot more concentrate needed now. If we use the same ratio of 28k tonnes PSG / 105 k tonnes concentrates this equates to 225k tonnes concentrates now needed to produce the upper limit 60 k tonnes of PSG that is currently in MOU status. These figures are from 2019 so improvements from the optimisation testwork may have changed this.

40 years x 225,000 tonnes concentrates = 9 M tonnes of concentrates needed over LOM.

To produce 9M tonnes of concentrates (94% recovery) you need a minimum of 9,576,000 tonnes contained.

The above example takes into account flake sizes reducing the total amount of useable feedstock but your point about size was one I completely overlooked. Not all of the contained graphite in resource will be useable. In Renascor's case 72.4% of the flake being small size will be useable according to this table from the 2019 DFS. Since the DFS, optimisation testwork and the expanded capacity feasibility studies may see improved recoveries of the ideal flake sizes.

So for 105,000 tonnes of concentrate about ~76,000 tonnes will be sent to the PSG plant to produce the 28,000 tonnes of PSG IMO. This correlates with what you mentioned re. 2 to 3 tonnes concentrate to make 1 tonne PSG.

So yes, you are absolutely correct my inebriated self was way too simplistic in my calculations. It seems like we will need to start firing up the drills to upgrade the confidence levels of our existing resource, and also to uncover some more tonnes at the nearby anomalies if we are to have a 40 year mine life. I have no doubt the tonnage is there, but it will take a fair bit of drilling to define it.

Anyway I'm just a mug punter who does his research and can get it completely wrong so DYOR.

GLA