Realistic Uranium Processing

Realistic Uranium Processing (RUP) replaces Factorio's simplified uranium
ore-to-isotope step with a multi-stage industrial fuel cycle while preserving the
vanilla-equivalent expected Uranium-235 and Uranium-238 output.

The goal is not to make nuclear power stronger or weaker. RUP expands the journey from
uranium ore to usable nuclear material into a more believable processing chain while
keeping the familiar late-game nuclear mechanics intact.

Process Chain

Uranium Ore
    ↓ crushing
Uranium Powder
    ↓ sulfuric-acid leaching
Yellowcake
    ↓ calcination
Uranium Oxide
    ↓ fluorination
Natural UF₆
    ↓ centrifuge enrichment
Enriched UF₆ / Depleted UF₆
    ↓ conversion
Enriched Uranium Pellets (U-235) / Depleted Uranium Pellets (U-238)

RUP also moves the use of sulfuric acid from uranium mining into the dedicated
leaching stage.

Features

Expanded Uranium Production

• Multi-stage processing from uranium ore to enriched and depleted uranium.
• Dedicated crushing, leaching, calcination, fluorine chemistry and UF₆ processing.
• Centrifuge enrichment using the original uranium isotope probabilities.
• Final products retain the vanilla uranium-235 and uranium-238 prototype IDs.

Vanilla-Equivalent Uranium Balance

For every 10 uranium ore processed through the complete fresh-uranium chain, the
expected average output remains equivalent to vanilla:

• 0.007 Uranium-235
• 0.993 Uranium-238

The enrichment step preserves Factorio's independent probabilistic behavior rather
than replacing it with a deterministic split.

Existing fuel-cell, nuclear-fuel, Kovarex and downstream uranium-consuming recipes
remain compatible because RUP returns the process to the original uranium isotope
items.

Controlled Productivity and Fluorine Recycling

Productivity support is defined explicitly for every RUP recipe.

The UF₆ conversion chain is protected against positive reagent loops:

• 5 units of elemental fluorine are required per UF₆ cycle.
• 4 units are recovered during isotope conversion.
• Fluorine recovery is therefore 80%.
• Recovered fluorine is excluded from productivity bonuses.
• Hydrogen fluoride and natural UF₆ production do not allow productivity.

This keeps the fluorine loop intentionally negative even when productivity modules
are used elsewhere in the chain.

Spent Fuel Reprocessing

RUP replaces the simplified vanilla reprocessing step with its own recovery chain:

Depleted Uranium Fuel Cell
    ↓ crushing
Spent Uranium
    ↓ chemical leaching
Yellowcake
    ↓
Normal RUP Uranium Processing Chain

When Krastorio 2 is installed, spent-uranium leaching can additionally recover
kr-tritium with a 10% independent probability.

Factory Planner Friendly

The process is built from normal Factorio recipes and technologies and is intended to
remain readable in production-planning tools.

RUP uses explicit main products, controlled productivity rules and a single shared
Yellowcake route for both fresh uranium and recovered spent fuel.

Compatibility

Factorio

• Factorio 2.1
• Requires Base >= 2.1.20
• Validated against Factorio 2.1.23

Krastorio 2

RUP detects Krastorio 2 automatically and reuses compatible existing materials and
machines where available.

Supported integration includes:

• Existing hydrogen instead of a duplicate fallback fluid.
• Existing sand/silica feedstock where available.
• kr-crusher support for RUP crushing recipes.
• Optional kr-tritium recovery during spent-fuel reprocessing.

Space Exploration

Space Exploration is supported directly.

RUP keeps its uranium chain in normal planetary recipe categories and integrates
appropriate SE machines without assigning the custom rup-crushing category to
space-only mechanical laboratories.

In the combined K2 + SE profile, rup-crushing is available on:

• kr-crusher
• se-pulveriser

A full startup with Factorio 2.1.23, Krastorio 2 2.1.4,
Space Exploration 0.7.63 and MOSII-SEI 2.1.8 has been validated successfully.

BZ Silica & Silicon

Optional integration is provided for BZ Silica & Silicon (bzsilicon).

When compatible silica or sand already exists, RUP reuses that material for fluorine
production instead of creating its own fallback sand item.

Compatibility Notice

RUP intentionally replaces the vanilla:

• uranium-processing recipe
• nuclear-fuel-reprocessing recipe

The corresponding technology progression is preserved and redirected to the RUP
process chain.

Kovarex enrichment and downstream nuclear recipes are not replaced by RUP.

Because overhaul mods may modify uranium technologies, recipe categories or machines,
compatibility with very large modpacks should still be verified with a normal game
startup.

Design Philosophy

RUP is an industrial-process expansion, not a nuclear-power rebalance.

The core design rules are:

• Preserve vanilla-equivalent expected isotope output.
• Keep the final uranium items compatible with existing nuclear recipes.
• Use realistic processing stages where they improve the production chain.
• Avoid duplicate materials when supported mods already provide suitable ones.
• Prevent unintended positive recycling or productivity loops.
• Keep compatibility code explicit and predictable.

Planned Features

• Tailings processing.
• Advanced waste management.
• Expanded fluorine chemistry.
• Additional industrial integrations.

Diagnostics

If a compatibility issue occurs, search factorio-current.log for:

[RUP]

RUP logs detected compatibility profiles, selected materials, technology targets and
the machines enabled for its custom crushing category.