Cadmium FAQ

What does Cadmium add?

Fume scrubbers that capture metal-bearing dust into filters, a washing step that recovers cadmium from them, and cadmium-plated hardware for engines, rockets and nuclear reactors. Scrubbers work faster in polluted chunks and remove some pollution while they run. There is no cadmium ore: it all comes from the air around your factory, or from the planet-specific sources in Space Age. Factorio 2.1.23 or later in the 2.1 series is required; Space Age is optional.

What are the recipes?

These are the Fluffy-only starter recipes. External material packs add the production stages described in this FAQ.

These are the base recipes before quality. Acid quantities are fluid units. Scrubbing times are at crafting speed 1.

Removal is at base speed with plain filters. Impregnated filters double it without using more power.

Cadmium has four core technologies. Fume scrubbing (red and green, after sulfur processing) unlocks scrubbers, filters, washing and plates. Cadmium plating (red and green, after engines) unlocks plated hardware and the engine recipe; the rail recipe unlocks with Railway. Electrostatic precipitation needs blue science and Impregnated filters purple. With Krastorio 2, Purifier filter leaching is added, and with If Nickel, Nickel-cadmium batteries. With Molybdenum, advanced oil processing comes after Cadmium plating.

Can research improve cadmium yield?

Yes. Cadmium refining productivity adds 10% productivity per level to sponge smelting. Without Space Age it unlocks after impregnated filters and uses red, green, blue and purple science. With Space Age it requires Electromagnetic science and Fume scrubbing and uses red, green, blue, space and electromagnetic science. It costs 1,500 of each for the first level, 2,250 for the second, then 50% more per level. Each research unit takes 60 seconds at lab speed 1. Five completed levels turn 100 sponge into 150 plates before module bonuses. Existing levels survive the Space Age research change.

It benefits sponge from every source, including optional phosphorus dust and zinc recovery. Washing, returned filters and trace byproducts are unaffected. Plate smelting also accepts productivity modules. Research and modules share the normal +300% total cap (four plates per sponge); levels beyond that cap add no further output. Existing saves gain the unresearched technology without losing completed research or production.

Overhauls retain their own science progression. Space Exploration splits the infinite research into successive space-science tiers; each level still adds 10% to plate refining.

How do fume bands work?

Every few seconds Cadmium reads the pollution of each chunk that contains scrubbers and divides it by the number of scrubbers in that chunk. That share sets each scrubber's band:

Sponge output, pollution removal and power use rise together. A scrubber keeps its band until the share drops below 85% of the threshold, so a scrubber that cleans its own chunk does not flicker between bands. Alt-mode shows the current bonus above each scrubber.

Crowding many scrubbers into one chunk splits its fumes between them. Spread them over the dirty chunks around your furnaces and boilers instead. Speed from your own beacons adds to the fume bonus.

The Fume band threshold multiplier map setting scales the 50, 150 and 400 thresholds. Faster scrubbing in polluted areas turns the bands off; scrubbers then always run at base speed.

Does Cadmium work with pollution turned off?

Yes. Scrubbers run at base speed and cadmium production works normally; there is no fume bonus and nothing to clean. A fume scrubber then supplies 2.5 sponge per minute. For 45 chemical science per minute, with every engine using plated bearings, plan on 2 fume scrubbers or 1 precipitator. With pollution enabled, a basic scrubber supplies 3.75 sponge/minute at +50% or 5 at +100%, so strategic placement lowers the count.

Do scrubbers really clean the air?

A little early on, noticeably later. A fume scrubber removes 2 pollution per minute at base speed, but on steam power its own 90 kW emits 1.5 of that back, so it keeps a quarter. A precipitator on steam keeps about half, and three quarters with impregnated filters. On solar or other clean power, scrubbers keep all of it: 20 precipitators at +50% remove 240 pollution per minute, about a sixth of what a 45 SPM base emits.

Treat the first scrubbers as a cadmium source rather than a pollution fix. The washing chemical plants add a little pollution of their own. The Scrubber pollution removal startup setting scales removal; at 0, scrubbers are a pure cadmium source.

Why can't I build scrubbers on Vulcanus, Fulgora, Aquilo and Gleba?

Scrubbers capture airborne pollution, and only Nauvis has it. Vulcanus, Fulgora and Aquilo have no airborne pollutant, and Gleba's is spores. Scrubbers therefore need the air pressure of a planet with airborne pollution: 1000 hPa, Nauvis's, unless another mod adds such a planet. That keeps them off the other planets and space platforms. On a modded planet with that pressure but no pollution, a scrubber shows "No airborne pollution on this surface" and stops. Scrubbers built elsewhere before version 0.3.7 stay where they are, switched off.

The other planets get their own sources:

• Vulcanus: molten copper from lava with fume capture runs in a foundry: 2,000 lava, 4 calcite and 1 scrubber filter make 1,000 molten copper, 60 stone and 1 loaded filter in 64 seconds. Wash the loaded filter for sponge. Foundry and Fume scrubbing unlock it before the big mining drill. Filters can be made locally from steel and coal. Acid neutralisation with its 5% sponge chance remains available alongside ordinary acid neutralisation, with calcite processing.
• Fulgora: scrap leaching in a chemical plant turns 20 scrap and 40 sulfuric acid into 1 sponge, 2 iron plates and 1 copper plate in 4 seconds. It needs Fulgora's magnetic field (99), so it also works on modded planets with the same field, and is unlocked with Recycling.
• Gleba: biosorption in the biochamber turns 10 spoilage, 1 bioflux and 10 sulfuric acid into 1 sponge in 8 seconds. Bioflux processing and Fume scrubbing unlock it before agricultural science. Biosulfur supplies sulfur for local acid; the biochamber runs on locally made nutrients.
• Aquilo and space platforms import cadmium and plated hardware. Hardware weighs 1 kg, so one rocket carries 1,000.

Scrap leaching and acid neutralisation do not accept productivity. Biosorption does: a normal biochamber produces 22.5 sponge per minute with its built-in bonus. Lava fume capture accepts productivity for copper and stone, but never for the loaded filter; it cannot raise filter quality. Washing also cannot raise cartridge quality.

With Space Age, foundries can smelt cadmium plates and electromagnetic plants can plate hardware. The hardware recipe accepts productivity up to +300%; a normal electromagnetic plant makes 6 hardware per plate before modules. Cryogenic plants run cadmium chemistry, including filter washing, impregnated filters, hardware and scrap leaching. Furnaces and chemical plants remain available, and Tellurium/Phosphorus washing variants inherit the cryogenic category. The in-game Space Age tip lists these routes when you reach a second planet.

Which planet mods does it support?

• Paracelsin: Zinc purification also recovers cadmium sponge.

Which vanilla recipes change?

• Rocket part: +2 plated hardware without Space Age (200 per rocket), +1 with Space Age or Space Exploration.
• Flying robot frame: +1 plated hardware.
• Roboport +5, steam turbine +5 (not with Space Age), centrifuge +10 and (Space Age) big mining drill +10 plated hardware.
• Nuclear reactor: +50 neutron absorber assemblies; portable fission reactor +5. The assembly unlocks with the research of whichever of these comes first.
• Fusion reactor (Space Age, Krastorio 2) +50, nuclear locomotive (Krastorio 2) +10 and portable fusion reactor (Space Exploration) +5 neutron absorber assemblies.
• The research that unlocks each of these requires Cadmium plating.
• Engine unit and rail: unchanged. The plated recipes are alternatives: engines use about a third less iron, rails twice as many per steel and iron stick.

Building charges only apply where the building's research already comes after sulfur processing, so Cadmium never delays early machines such as trains. With Space Age, steam turbines are left alone: they are the first power on Vulcanus, Gleba and Aquilo, which have no cadmium of their own at that point. Other ingredients are preserved. Each change can be bypassed; see below.

How do the absorber upgrades work?

The standard assembly uses two cadmium plates, two steel plates, two stone bricks and one plated hardware. With Magnesium, two magnesia replace the bricks when their research fits every existing assembly unlock; otherwise bricks remain. The reactor research gains the material prerequisite without gaining a science tier.

With Neodymium, Dysprosium-assisted absorbers is separate research after Heavy rare earths, Nuclear power and Cadmium plating: 150 red, green, blue and yellow packs, 30 seconds each (overhaul prerequisite packs are inherited). It unlocks an optional batch of 20 ordinary assemblies, using one dysprosium oxide to replace 20 cadmium plates. Steel, ceramic lining, hardware and crafting time per assembly stay the same. The direct cadmium charge halves; including the hardware it falls from 2.25 to 1.25 plates per assembly. The standard route remains available before yellow science.

When upgrading from 0.3.5, existing absorber assemblers retain their recipe but need the new steel, lining and hardware supplied. Existing reactors and stored assemblies are unchanged; the optional technology still needs researching. Add cadmium-neutron-absorber to Unmodified recipes to keep the brick lining, or cadmium-neutron-absorber-dysprosium to omit the optional recipe and research.

What happens with Krastorio 2?

Cadmium plays the same way as without K2, including the 4×4 electrostatic precipitator and the same research. K2's own air purifier stays K2's pollution cleaner, and Cadmium does not change it. Purifier filter leaching (after K2's air purification and Fume scrubbing) washes a used pollution filter with 25 sulfuric acid into 3 cadmium sponge, returning the filter 80% of the time; K2's own biomass restore recipe stays.

With Brass Tacks as well, zinc enrichment with cadmium recovery is an optional variant of K2's enrichment: 2 more sulfuric acid and a 2.5% chance of cadmium sponge per zinc ore. The ordinary enrichment is unchanged.

How does Cadmium work with Tellurium?

Tellurium is optional. When it is installed:

• Each filter wash gets a variant with tellurium recovery. It uses 20 sulfuric acid instead of 10 and adds a 10% chance of one tellurium residue. Plain filters return 70% of the time instead of 80%; impregnated filters return 85% instead of 90%. Both routes therefore need 50% more replacement filters. Phosphorus's derived phosphoric-acid recipes inherit this wear. The ordinary washes stay, so the byproduct is your choice. The plain variant unlocks with Fume scrubbing, the impregnated one with Impregnated filters.
• When your Tellurium version puts one tellurium metal into each batch of solar panels, Cadmium replaces it with cadmium telluride: one cadmium plate and one tellurium metal, crafted in 4 seconds. The panels still carry just one charge. Solar energy research then requires Fume scrubbing. With Tellurium 0.2.1 and Krastorio 2 the same swap applies to advanced solar panels (1 per 4 panels).

Filter washing is an alternative source alongside Tellurium's own recovery. At base speed, a fume scrubber supplies filters for 0.25 residue per minute and a precipitator for 0.75, before pollution bonuses. Each recovery wash still costs 20 acid, wears more filters, and averages 0.1 residue; faster capture changes the required building count rather than this cost per residue.

What about Space Exploration and Brevven's mods?

Space Exploration: every cargo rocket section needs 2 plated hardware and satellites' rocket parts need 1 each. Cadmium sponge, plates and hardware can be shipped by delivery cannon. Scrubbers work on planets and moons with airborne pollution. With Tellurium installed too, each gamma-ray detector and each night vision equipment needs one detector crystal — cadmium zinc telluride (1 cadmium + 1 zinc + 1 tellurium → 2) where Brass Tacks zinc exists, cadmium telluride (1 cadmium + 1 tellurium → 1) otherwise — unlocked with the gamma-ray telescope or night vision.

Brass Tacks: zinc purification supplies cadmium alongside zinc production. It refines zinc in a chemical plant with sulfuric acid — as fast per building as a steel furnace, never faster — and recovers one sponge per 40 zinc ore (0.9375 sponge/minute per plant). Ordinary zinc smelting keeps working; the recipe unlocks with Fume scrubbing. Under Krastorio 2 it keeps K2's zinc yield.

If Nickel: nickel-cadmium batteries make 4 batteries from 2 nickel, 1 cadmium plate, 4 iron and 40 water — no lead, zinc, graphite or acid. The ordinary battery recipe stays. Research Nickel-cadmium batteries after Fume scrubbing and Battery.

What does Cadmium cost in UPS?

Very little. Scrubbers are ordinary crafting machines; each has a hidden beacon that carries its fume bonus. A small script checks a few chunks every 12 ticks, visiting every chunk with scrubbers about every five seconds. In a benchmark with 1,000 fume scrubbers, four per chunk in 250 polluted chunks, the script averaged 0.019 ms per tick, with a 99th percentile of 0.26 ms and a maximum of 0.32 ms (Factorio 2.1.22).

Can I add Cadmium to an existing save?

Yes. No map regeneration is needed because no resources are placed. When you load the save, research you have already completed unlocks its Cadmium recipes.

From then on, rocket parts, flying robot frames, roboports, steam turbines (without Space Age), centrifuges, big mining drills, nuclear and fusion reactors and portable reactors need plated parts or absorbers (cargo rocket sections too with Space Exploration, and gamma-ray detectors and night vision need detector crystals with Space Exploration and Tellurium). Robot frame and rocket part production stops until you have plated hardware, so research Fume scrubbing and Cadmium plating and build a few scrubbers soon after adding the mod, or list those recipes under unmodified recipes until you are ready. Back up your save first.

Can I remove Cadmium?

Yes, but back up your save first. Factorio removes Cadmium's buildings, items and recipes from the save, including filters and hardware in chests and the hidden beacons behind the fume bonus. The recipes Cadmium charged go back to their ordinary ingredients. Pollution the scrubbers were removing is no longer absorbed.

Can I bypass a recipe change?

Use the Unmodified recipes startup setting, with comma-separated internal recipe names. It accepts:

• Host recipes Cadmium changes: rocket-part, flying-robot-frame, roboport, steam-turbine, centrifuge, big-mining-drill, nuclear-reactor, fission-reactor-equipment, fusion-reactor, kr-fusion-reactor, kr-nuclear-locomotive, se-fusion-reactor-equipment, se-cargo-rocket-section, and with Tellurium solar-panel, kr-advanced-solar-panel, se-gammaray-detector and night-vision-equipment.
• Cadmium's alternatives: cadmium-engine-unit, cadmium-rail, cadmium-acid-neutralisation, cadmium-scrap-leaching, cadmium-zinc-purification, cadmium-enriched-zinc, cadmium-nickel-battery, cadmium-filter-washing-tellurium and cadmium-impregnated-filter-washing-tellurium.

A bypassed host recipe keeps its ingredients, and its research does not gain a Cadmium prerequisite. A bypassed alternative is not added. Log Cadmium changes writes every recipe and research change to the Factorio log.

What do the other settings do?

• Scrubber pollution removal (startup, 0–4, default 1): multiplies how much pollution scrubbers remove. At 0 they are a pure cadmium source.
• Faster scrubbing in polluted areas (map, default on): turns the fume bands on or off.
• Fume band threshold multiplier (map, 0.1–10, default 1): scales the pollution needed per scrubber for each band.

What do the material-pack integrations add?

Loaded filters produce cadmium leachate. Alkali and reductant turn it into a dry reduction charge for a furnace or foundry; the resulting sponge is refined into metal. Hardware production also needs plating electrolyte. Existing direct planetary sponge sources keep their role, and native filter media, bolts and other parts connect the workshop to its providers.

Will this change my Fluffy-only factory?

Fluffy-only games keep their existing recipes, machines and progression, with or without Space Age. The extra requirements activate only with the relevant external material providers. They do not add machinery requirements to a normal Fluffy-only game.

How should I update a factory that uses material packs?

Back up your save and update the Fluffy material mods you already use together. You do not need to install additional siblings. Existing external production lines may need new ingredient feeds, intermediate transfers or a different crafting machine. Saved materials and recipe references are preserved; check around machines for returned stock after upgrading.

The matching versions are listed in the Caesium FAQ. The companion mods remain optional.

Provider conflicts still apply. BZ + Trikop is supported; Manganese on its own has an upstream steel-furnace limitation that can block progression. Space Exploration and Space Age are separate configurations.