Cadmium

Your smelters are full of cadmium. Right now it goes up the chimney.

Fume scrubbers pull that metal-bearing dust out of the air around your furnaces and boilers into filters, and clean up a little pollution while they're at it. Wash the loaded filters for cadmium, plate steel parts with it, and you get cheaper engines, and the hardware your rockets and nuclear reactors need. The dirtier the air around a scrubber, the faster it works, so the smokiest corner of your factory becomes your best cadmium mine.

It starts after sulfur processing. There are no ore patches to find: put scrubbers among your furnaces and boilers, keep them supplied with filters, and wash what comes back.

Factorio 2.1.23 or later. Space Age is optional.

What it adds

The starter recipes below describe a Fluffy-only game. With external material packs, the filter loop grows into the refinery described below.

• Fume scrubbers, with red and green science. A scrubber turns a filter (steel and coal) into a loaded filter every 24 seconds and removes a little pollution while it runs.
• Filter washing in a chemical plant with sulfuric acid: one cadmium sponge per filter, and the filter comes back 80% of the time. Smelt the sponge into cadmium plates.
• Cadmium-plated hardware: one plate, one steel and a little acid make four.
• Engine with plated bearings: 2 steel, 2 gears, 2 pipes and 1 hardware make 3 engines, about a third less iron per engine. The ordinary engine recipe stays.
• Rocket parts need plated hardware: two per part without Space Age, one with it.
• Rails with plated fasteners: twice the rails per steel and iron stick. The ordinary rail recipe stays.
• Flying robot frames need one plated hardware; roboports, centrifuges, Space Age's big mining drill and, without Space Age, steam turbines need a few. Only buildings whose research already comes after sulfur processing are charged.
• Nuclear reactors need 50 neutron absorber assemblies, each made from 2 cadmium plates, 2 steel, 2 ceramic lining and 1 plated hardware. Fusion reactors (Space Age, Krastorio 2) need 50 too, Krastorio 2's nuclear locomotive 10, and portable fission reactors (and Space Exploration's portable fusion reactor) 5.
• Electrostatic precipitators, with blue science: a 4×4 scrubber with three times the throughput and four times the pollution removal.
• Impregnated filters, with purple science: treated filters that scrub twice as hard and yield one or two sponge per wash.
• Cadmium refining productivity: repeatable research adds 10% plate productivity per level. Without Space Age it follows impregnated filters and costs red, green, blue and purple science. With Space Age it follows electromagnetic science and fume scrubbing and costs red, green, blue, space and electromagnetic science. Starts at 1,500 of each, then costs 50% more each level. Five levels turn 100 sponge into 150 plates before module bonuses. Research and modules share a +300% cap.

Fume bands

With pollution enabled, a scrubber works faster the dirtier its chunk is. The chunk's pollution is shared among all scrubbers in it. Below 50 per scrubber they run at base speed; from 50, 150 and 400 they gain +50%, +100% and +150% speed, and use that much more power. Alt-mode shows the bonus above each scrubber.

With pollution disabled, scrubbers simply run at base speed, so cadmium production works in every game.

Early scrubbers barely dent pollution: on steam power, their own electricity cancels most of what they remove. Real cleanup needs precipitators, impregnated filters and clean power.

Space Age

Only Nauvis has airborne pollution, so scrubbers can only be built where the air pressure matches Nauvis (1000 hPa). That keeps them off the other planets and space platforms. The other planets have their own sources:

• Vulcanus: foundry fume capture. 2,000 lava, 4 calcite and one scrubber filter make 1,000 molten copper, 60 stone and one loaded filter in 64 seconds. Wash the filter for sponge. Unlocked with Foundry and Fume scrubbing, before the big mining drill. Acid neutralisation remains an optional source.
• Fulgora: scrap leaching. 20 scrap and 40 sulfuric acid give one sponge, two iron and one copper in 4 seconds. Unlocked with recycling. Electromagnetic plants plate hardware with their built-in productivity bonus: six hardware per plate before modules.
• Gleba: biosorption in the biochamber. 10 spoilage, one bioflux and 10 sulfuric acid make one sponge in 8 seconds. Unlocked with Bioflux processing and Fume scrubbing, before agricultural science. Biosulfur supplies local sulfuric acid.
• Aquilo and space platforms import cadmium and plated hardware. Hardware weighs 1 kg, so one rocket carries 1,000.

Foundries also smelt cadmium plates, and cryogenic plants run cadmium chemistry. Furnaces and chemical plants remain available. An in-game Space Age tip lists the sources when you reach another planet.

Planet mods

• Paracelsin: Zinc purification also recovers cadmium sponge.

Turn the filter loop into a refinery

With BZ, Trikop, Timeken and Planetfall/Ashier materials, washing filters opens a longer production line. Leach the captured dust, prepare dry reduction charges, reduce the metal in furnaces or suitable foundries, then mix plating electrolyte for your hardware.