In other languages: Deutsch Français 日本語 한국어 Polski Русский Українська 简体中文

Kovarex enrichment process: Difference between revisions

From Official Factorio Wiki
Jump to navigation Jump to search
m (→‎Trivia: I found you a source :))
(Added section on use and significance in managing U235 / U238 mix, another section on reaching the initial 40 U-235 needed (prob. math), some RW trivia. Admins: Suggest consider removing Stub tag.)
Line 5: Line 5:
The '''Kovarex enrichment process''' is a method for reprocessing uranium in a [[centrifuge]]. Although the process requires a large amount of (much rarer) Uranium-235 to start, it can be a good way to get more use out of the available [[uranium ore]].
The '''Kovarex enrichment process''' is a method for reprocessing uranium in a [[centrifuge]]. Although the process requires a large amount of (much rarer) Uranium-235 to start, it can be a good way to get more use out of the available [[uranium ore]].


It is highly recommended to avoid consuming nuclear fuel until the Kovarex process has been initiated. Once it is active, the abundance of U238 can be converted to U235 to ensure a steady supply of fuel rods. Automating this process requires a bit of thought because the output materials are also the input materials.
It is highly recommended to avoid consuming nuclear fuel until the Kovarex process has been initiated. Once it is active, the abundance of U-238 can be converted to U-235 to ensure a steady supply of fuel rods. Automating this process requires a bit of thought because the output materials are also the input materials.
 
== Purpose ==
[[Uranium processing]] takes 10 uranium ore and returns 1 [[Uranium-235]] with 0.007 (0.7%) probability, or 1 [[Uranium-238]] with 0.993 (99.3%) probability, leading to an [https://en.wikipedia.org/wiki/Binomial_distribution expected] (not guaranteed!) 1 unit of Uranium-235 per approximately 143 processing cycles (or about a 1:142 ratio of U-235 to U-238). This is currently the only probability-based crafting recipe in the game.
 
Uranium-235 is necessary to create [[Uranium fuel cell]]s and [[Atomic bomb]]s, in considerable quantities for the latter, but the probability distribution of uranium processing leads to it being produced slowly and creating large stockpiles of U-238 as a byproduct. The Kovarex process thus provides the player with a use for the surplus U-238.
 
It should be noted that U-238 is not useless; it is necessary (and sufficient) to manufacture [[Uranium rounds magazine]]s, [[Uranium cannon shell]]s, and [[Explosive uranium cannon shell]]s, and is required as a secondary ingredient in Uranium fuel cells. Therefore, it is not advisable to use the Kovarex process to convert ''all'' stockpiled U-238 into U-235. (Although, in case of shortage, [[Used up uranium fuel cell]]s can be [[Nuclear fuel reprocessing|reprocessed]] into a modest amount of U-238.)
 
== Requirements for initiation ==
Unlike all other crafting processes in the game, Uranium processing creates U-235 and U-238 based on probability, rather than in guaranteed deterministic amounts. Additionally, the Kovarex process requires a bulk stockpile of 40 units of the rare Uranium-235 isotope to initiate in a single centrifuge. Therefore, planning uranium mining and processing for the Kovarex process takes certain considerations not encountered elsewhere in the game.
 
=== Expected value ===
As U-235 is created in centrifuges running Uranium processing with ''p = 0.007'', the expected number of processing cycles to gain a single unit is ''E(1,p) = 1 ÷ p = ~143''. The expected number of cycles to gain 40 units is then ''E(40,p) = 40 × E(1,p)'' = '''~5,714 cycles'''. Note that running this many cycles requires mining 57,140 Uranium ore, a non-trivial task.
 
However, given the nature of probability, it is impossible to guarantee that 40 units will be reached in this number of cycles; as a matter of fact, some mathematics yields that the probability that 5,714 cycles will produce ''at least'' 40 units of U-235 is only about 52%.
 
=== Confidence levels ===
[[File:Kovarex-prob-chart.png|300px|thumb|right|Probability of reaching 40 U-235 from Uranium processing by number of cycles (click to enlarge)]]
 
Some further mathematics enables one to calculate the number of Uranium processing cycles one must run to obtain ''at least'' 40 units of U-235 (given ''p = 0.007'') with a given level of confidence (probability of achieving the set goal).
 
As discussed in the previous section, the level of confidence corresponding to 5,714 cycles (for which the ''expected value'' of U-235 gained is 40) happens to be about 52% (or, in other words, with this number of cycles, one can expect to fail to reach 40 U-235 a bit less than once out of every 2 tries).
 
Some further example confidence levels that may be of interest to players are given in the table below. Consult the chart to the right for custom values.
 
{| class="wikitable" style="text-align: center;"
!style="width: 120px;" |Confidence level
!style="width: 100px;" |Failures
!Cycles required
|-
| 10% || 9 out of 10 || 4,595
|-
| 50% || 1 out of 2 || 5,667
|-
| 90% || 1 out of 10 || 6,894
|-
| 95% || 1 out of 20 || 7,272
|-
| 99% || 1 out of 100 || 8,015
|-
|}


== Trivia ==
== Trivia ==
* The Kovarex enrichment process is named after [[development-team|Michal Kovařík]], lead designer of Factorio and co-owner of Wube, whose online nick is ''kovarex'' (which he usually spells lowercase). [https://www.reddit.com/r/factorio/comments/67bj3p/015_kovarex_uranium_enrichment_is_too_good_with/dgq2ij3/?context=1]
* The Kovarex enrichment process is named after [[development-team|Michal Kovařík]], lead designer of Factorio and co-owner of Wube, whose online nick is ''kovarex'' (which he usually spells lowercase). [https://www.reddit.com/r/factorio/comments/67bj3p/015_kovarex_uranium_enrichment_is_too_good_with/dgq2ij3/?context=1]
* In the real world, [https://en.wikipedia.org/wiki/Uranium-235 uranium-235] is the only fissile isotope of uranium and makes up approximately 0.72% of naturally-occurring uranium, with the other 99.28% being [https://en.wikipedia.org/wiki/Uranium-238 uranium-238]. The in-game representation is thus highly accurate in this regard. Uranium is commonly [https://en.wikipedia.org/wiki/Enriched_uranium enriched] in centrifuges to increase the percentage of 235U for use in fission reactions.
:* Uranium munitions are made from [https://en.wikipedia.org/wiki/Depleted_uranium depleted uranium], a byproduct of uranium enrichment, which is mostly 238U whose natural admixture of the 235U isotope has been lowered even further through the enrichment process. Depleted uranium is minimally radioactive and the reason for its use in munitions is its very high density and other mechanical properties, not radioactivity / toxicity.


== History ==
== History ==

Revision as of 18:56, 26 September 2017

No-building-material-icon.png
This article is a stub, and not comprehensive.
You can help this wiki by expanding it.
Kovarex enrichment process.png
Kovarex enrichment process

Recipe

Time.png
60
+
Uranium-235.png
40
+
Uranium-238.png
5
Uranium-235.png
41
+
Uranium-238.png
2

Total raw

Time.png
60
+
Uranium-235.png
40
+
Uranium-238.png
5

Prototype type

recipe

Internal name

kovarex-enrichment-process

Required technologies

Kovarex enrichment process (research).png

Produced by

Centrifuge.png

The Kovarex enrichment process is a method for reprocessing uranium in a centrifuge. Although the process requires a large amount of (much rarer) Uranium-235 to start, it can be a good way to get more use out of the available uranium ore.

It is highly recommended to avoid consuming nuclear fuel until the Kovarex process has been initiated. Once it is active, the abundance of U-238 can be converted to U-235 to ensure a steady supply of fuel rods. Automating this process requires a bit of thought because the output materials are also the input materials.

Purpose

Uranium processing takes 10 uranium ore and returns 1 Uranium-235 with 0.007 (0.7%) probability, or 1 Uranium-238 with 0.993 (99.3%) probability, leading to an expected (not guaranteed!) 1 unit of Uranium-235 per approximately 143 processing cycles (or about a 1:142 ratio of U-235 to U-238). This is currently the only probability-based crafting recipe in the game.

Uranium-235 is necessary to create Uranium fuel cells and Atomic bombs, in considerable quantities for the latter, but the probability distribution of uranium processing leads to it being produced slowly and creating large stockpiles of U-238 as a byproduct. The Kovarex process thus provides the player with a use for the surplus U-238.

It should be noted that U-238 is not useless; it is necessary (and sufficient) to manufacture Uranium rounds magazines, Uranium cannon shells, and Explosive uranium cannon shells, and is required as a secondary ingredient in Uranium fuel cells. Therefore, it is not advisable to use the Kovarex process to convert all stockpiled U-238 into U-235. (Although, in case of shortage, Used up uranium fuel cells can be reprocessed into a modest amount of U-238.)

Requirements for initiation

Unlike all other crafting processes in the game, Uranium processing creates U-235 and U-238 based on probability, rather than in guaranteed deterministic amounts. Additionally, the Kovarex process requires a bulk stockpile of 40 units of the rare Uranium-235 isotope to initiate in a single centrifuge. Therefore, planning uranium mining and processing for the Kovarex process takes certain considerations not encountered elsewhere in the game.

Expected value

As U-235 is created in centrifuges running Uranium processing with p = 0.007, the expected number of processing cycles to gain a single unit is E(1,p) = 1 ÷ p = ~143. The expected number of cycles to gain 40 units is then E(40,p) = 40 × E(1,p) = ~5,714 cycles. Note that running this many cycles requires mining 57,140 Uranium ore, a non-trivial task.

However, given the nature of probability, it is impossible to guarantee that 40 units will be reached in this number of cycles; as a matter of fact, some mathematics yields that the probability that 5,714 cycles will produce at least 40 units of U-235 is only about 52%.

Confidence levels

Probability of reaching 40 U-235 from Uranium processing by number of cycles (click to enlarge)

Some further mathematics enables one to calculate the number of Uranium processing cycles one must run to obtain at least 40 units of U-235 (given p = 0.007) with a given level of confidence (probability of achieving the set goal).

As discussed in the previous section, the level of confidence corresponding to 5,714 cycles (for which the expected value of U-235 gained is 40) happens to be about 52% (or, in other words, with this number of cycles, one can expect to fail to reach 40 U-235 a bit less than once out of every 2 tries).

Some further example confidence levels that may be of interest to players are given in the table below. Consult the chart to the right for custom values.

Confidence level Failures Cycles required
10% 9 out of 10 4,595
50% 1 out of 2 5,667
90% 1 out of 10 6,894
95% 1 out of 20 7,272
99% 1 out of 100 8,015

Trivia

  • The Kovarex enrichment process is named after Michal Kovařík, lead designer of Factorio and co-owner of Wube, whose online nick is kovarex (which he usually spells lowercase). [1]
  • In the real world, uranium-235 is the only fissile isotope of uranium and makes up approximately 0.72% of naturally-occurring uranium, with the other 99.28% being uranium-238. The in-game representation is thus highly accurate in this regard. Uranium is commonly enriched in centrifuges to increase the percentage of 235U for use in fission reactions.
  • Uranium munitions are made from depleted uranium, a byproduct of uranium enrichment, which is mostly 238U whose natural admixture of the 235U isotope has been lowered even further through the enrichment process. Depleted uranium is minimally radioactive and the reason for its use in munitions is its very high density and other mechanical properties, not radioactivity / toxicity.

History

  • 0.15.2:
    • No longer usable with productivity modules.

See also