I'm developing fictional technology for "perfect recycling."

  • A large plant that takes in water and every cubic millimeter of waste humanity can produce (in the local area, of course).

  • It disintegrates (for lack of a better description) the waste and water. Sea water is used to "balance" the process (to ensure as much mass as the reaction requires is used such that the reaction neither dies for lack of material nor runs away for having too much).

  • One output is distilled water, which is used for drinking water, irrigation, whatever might be needed.

  • The other output is materialized "goods" such as raw metals, wood (lumber), plastic, chemicals, etc.

The basis of the story is the political impact of having such a facility in different areas of a future Earth and the corruptible power-grab likely to happen when it is introduced to the world. Can you imagine how the average person living in central Africa would react? or the warlord trying to control said person? Or how the waste management companies of first-world countries would react? or timber and mining companies? But I digress....

Question: what technologies today or in the near future could be used to make this recycling plant believable?

  • You might be tempted to believe I'm looking for Star Trek replication and transporter technology. It's the right idea, but not the solution I'm looking for. What my story will have could be considered a very, very early ancestor of such technology. Much closer to us than it is to Jean-Luc Picard.

  • Whether one or several technologies, I'm looking for something that can (with a helping of Clarkean Magic) handle everything. An example of the problem is that metals, for example, are easy(ish). Add heat to different amounts and they can be separated. But heat alone would destroy almost everything else and I'm not looking to have to separate the recyclables. Ideally, I am looking for technologies that could lead to molecular disintegration and reintegration.

  • While the story will have a plant that enjoys 100% reutilization (no waste products, no toxins unless intentionally produced for resale, etc.), that is obviously not a requirement for any of the supporting technologies I'm looking for.

  • I'm looking for suspension of disbelief, but I'm not looking for just anything. The accepted answer should propose technologies that meet the first four bullets along with brief explanations as to why they could support the fictional technology.

  • I am looking for more thorough answers than, for example, the answers to this question propose.

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    $\begingroup$ "Heat alone would destroy almost everything else": I would have thought that this is the entire point. Heat everything up to a point where everything is dissociated into a plasma, then use ordinary chemistry to separate the elements and combine them into whatever substances you want. I am troubled by the statement that "sea water is used to 'balance' the process" -- I cannot see how having an excess of hydrogen and oxygen would be helpful to compensate for a dearth of nitrogen, for example. Ah, and a factory converts urine into milk and ash into wood absolutely is a Star Trek replicator. $\endgroup$
    – AlexP
    Dec 17, 2017 at 8:45
  • $\begingroup$ @AlexP, I'm concerned that one material's heat is another material's combustion. Carbon I don't need. I might not have been clear enough in the question, but sea water is being used as a filler material. Whatever the process may be, if there isn't enough material to recycle for the sake of the process, sea water is added to make up the difference. Everybody can always use water. $\endgroup$
    – JBH
    Dec 17, 2017 at 9:22
  • 2
    $\begingroup$ drinking and using distilled water on crops is a really REALLY bad idea. There are a lot of dissolved micronutrients in water we need. This is even more important in plants and livestock who don't have alternative sources the way humans do. medicalnewstoday.com/articles/317698.php $\endgroup$
    – John
    Dec 17, 2017 at 13:59
  • $\begingroup$ @John, that's a good point, but now that I think about it, if my plant can re-integrate materials for resale, it could just as easily re-integrate a "potable" non-distilled water. I can change that in the story easily enough. $\endgroup$
    – JBH
    Dec 18, 2017 at 4:59

6 Answers 6


Genetically engineered recycling bacteria. Many varieties.

Plus (perhaps) some new acids to help them along with harder breaking.

The "natural" means of recycling for the Earth is biological decomposition, over time, breaking down compounds for consumption to create animal and plant bodies, which themselves can be recycled as feed for animals.

I have already read several articles in New Scientist, Scientific American and Science News (all magazines dedicated to pure actual science) about bioremediation, bacteria genetically engineered to to digest (break down) crude oil, concentrate radioactive elements from soil, plants that absorb and concentrate salts from soil in their roots or leaves, bacteria that can break down plastics and in turn become food for something else.

Our own gut bacteria (in basically all animals) is secreted by parietal cells in the stomach, for an adult human the product is two liters of hydrochloric acid a day to break down foods. but notice it is secreted by cells, which we can take as proof that engineered bacteria can secrete strong acids in a slurry tank, that do not destroy themselves but can break down "garbage".

For a fictional extension of this, presume detailed chemistry and understanding of how to genetically engineer bacteria to produce very specific compounds (like acids and catalysts) advance beyond their current capabilities. (Most of our genetic engineering at this point is learning to cut and paste a gene that exists in one organism, into another organism. We are not at the point of saying "I want sulphuric acid" and being able to compute, de novo, DNA sequence[s] that will produce sulphuric acid.)

Also, the fictional extension would have to include the idea that there is a reasonably finite number of engineered bacteria that can always get all of the job done, for recycling anything we produce, perhaps in the hundreds or thousands of different bacteria. That is fictional because we would need "generalizers", like our own parietal cells producing hydrochloric acid, that will break down large chunks of the millions of compounds we must break down. We don't want millions of bacteria for those millions of things.

Now arrange these into a Tree diagram, some hierarchy of treatments in your recycling plant. Each treatment is followed by a sorting of the products produced, different branches of the sorted products undergo more specific treatments, which again are followed by sortings, and more specific treatment.

In our own bodies, the stomach and its strong acid bath and bacteria there dissolve many bonds and turn the food into a slurry. That is then passed to the intestine, where up to 1000 different species of bacteria go to work processing it, so we can extract nutrients from the slurry. (I am being hand-wavy for brevity, see Gut Flora for a more detailed discussion.)

So imagine your recycling plant as an engineered digestive system. Imagine that processing tree as being far more complex, to deal with any garbage humans can deliver, including paint and lacquer and used petroleum products, glass and metal, unused (and used) medicines, industrial acids, everything.

Don't imagine ONE magic bullet. I would imagine this plant as a strong acid bath to start that "cleans" incoming garbage, a mechanical chopper that reduce everything to sand-sized particles, more baths, slurries, magnetic fields, etc that sort and process, sort and process, until you are left with things that DO require heat processes (metals and glass at least), and components, concentrated by those thousands of species of bacteria (most of which work in combinations, not alone), that can be turned back into products, fertilizers, ingredients, fuel (e.g. methane) or (through controlled indoor farming) new plant life (to absorb any carbon emitted in the processes).

Note also that heat and cold can be very effective in breaking down products without producing any carbon, both mechanically and chemically. The summer/winter cycle on Earth erodes mountains; water freezes and expands, and can break rocks doing it. You will notice much food with high moisture content (like fruits) become mushy if (at normal below freezing temps) frozen solid and then thawed; their cells were ruptured. "Freezer burn" is a similar process. Freeze and thaw meat several times, and without any bacterial rotting, it becomes very unappetizing. The same thing goes for heat: Cooking food breaks it down (and more digestible and doubles or triples the available calories, which means easier to digest by gut bacteria) without burning it.

The recycling plant is a giant digestive process. The majority of this is done just as nature does it, but we don't want to wait centuries for nature to get the job done. We do have some mineral products nature won't break down for many centuries; e.g. stainless steel, glass, mineral crystals (like diamond and sapphire we use). Those should be easy enough to identify and process separately on their own branches.

I would say feel free to add some sophisticated AI (not conscious or self-aware, but chemically all-knowing) to aid the sorting, it could use various testing mechanisms (lasers, sonograms, chemical probes) to decide how to break down some of those sand-sized grains.

Don't think that is too much work: Frito-Lay industries has AI devices that literally examine every single potato chip for discolorations before it goes into a bag, they can make these decisions in micro-seconds and process tens of thousands of chips per second. Your recycling AI can automatically investigate any grain it finds resistant to the mechanical processes, acids or other chemical decomposition processes, or unidentifiable and requiring greater attention, even if there are trillions of those grains per day to focus upon.

Plus it is fiction! The point is that this route is plausible, if only because all of our trash is decomposable some way or another in nature. Special circumstances might fossilize or preserve some things, in sap or bogs or ice or whatever, but your recycling plant is more like the typical course of refuse, or really the worst-possible-case course that causes it to be broken down and reabsorbed as soon as possible in nature. Then amped up by genetically engineered bacteria producing whatever we need to break down the most resistant compounds man has developed.


I know this is not what OP want, but "Easy Way" to have 100% recycling is "simply" to ban any building technology not based on biological processes.

Nowadays "hard to recycle" wastes are due to us using processes unavailable in the normal life cycle (high pressure/temperature, vacuum, etc.), this tends to produce things that cannot be recycled by ecosystem (e.g.: plastic).

OP asks for a generic recycler capable of eating whatever thrown at it; IMHO real answer would be not to produce what can't be readily recycled.

  • 1
    $\begingroup$ :-) This is a good point, but without the recycling plant, I don't have a story. $\endgroup$
    – JBH
    Dec 18, 2017 at 4:58

It will need a lot of different technologies and approaches. Goods should be made with the concept of recycling in mind, waste materials should be kept separate where possible and an efficient means of reusing unwanted items need to be introduced. The standard recycling methods can be used for paper, food waste, glass, aluminium, iron and many plastics with waste from these processes being fed into the lower level recycling methods mentioned below.

Once ‘reusables’ have been removed larger items need to be disassembled. Some of the disassembled items might also be reused, for example power supply units, cases etc Once there is nothing left to reuse remaining components can be shredded and further processed to separate smaller components and imbedded items of plastic, metal and glass for recycling as described above.

Remaining material could be burnt at high temperature and the major gasses chemically processed to produce a range of usable raw materials like carbonates and carbon dioxide. The carbon dioxide could be used as a feed stock for plants, or could be further processed chemically as required to make other chemicals by a range of different processes.

Finally there will be a true waste stream of sludge, grim, grot and unusable mixed chemical muck. This would require a massive amount of energy to process, but I suggest an ultra-high temperature burner could be used to turn the waste into a plasma destroying most chemical bonds. The resulting plasma could then be fed into a very large mass spectrometer like device where the ions in the plasma would be accelerated in a strong magnetic field sorting them by mass/charge.

The ‘detector’ from a traditional mass spectrometer would be replaced by a wide range of collectors where individual elements would accumulate. These relatively pure elements could then act as feed stock for manufacturing.

The trick with making this work would be to ensure that the waste stream for the last stage was as small as possible and there was a sufficiently large supply of energy to power it all.


How about simply having nanites that break things back down to the simplest state for re manufacturing? You could have them only work on inorganic matter as a safety precaution. They could be powered by something green like solar power.

I read somewhere about nanites that could literally mine for things like gold molecule by molecule. Imagine what that could do once refined and perfected? I also imagine powering them by a field of electromagnetism so they could only work in a limited area. You could set it up in a junk yard where there's already so much stuff.

Although, I have to say practically that no system would reuse 100% all of what's put into it. Something has to be spent and can't be passed on, or at least not for a very long time. We take in carbon through the carbon cycle. How long do you think it takes every single molecule to leave you, excluding death?

  • 2
    $\begingroup$ Welcome to WB:SE! There's something to be said for this answer, but it's a little short. Generally, the site asks for a paragraph or two to flesh out the answer. In this case, you suggest some pros and cons that can be expanded upon. Could you edit your answer to do that? $\endgroup$
    – JBH
    Dec 18, 2017 at 4:57

You are aiming to 100% recycling. This means you want to decompose any object into its prime constituents, which are currently chemically bound into the to-be-recycled object.

You need to:

  1. break the chemical bonds to free the atomic species: this can be done by provide enough energy, aka heat it up a lot until it is some sort of plasma.
  2. prevent that other unwanted chemical bonds are created between non similar species.
  3. bucket the species separately (Nitrogen with Nitrogen, Gold with Gold, you name it...)
  4. lower the energy of the buckets so that chemical bonds can be formed again: here is you can use water, which is a good coolant. Sea water evaporates and cool, and upon condensation it has lost all its salts.
  5. harvest the materials and use them at will.
  • $\begingroup$ This is a process, not a technology. It's interesting, but not what I was expecting. Note that the use of heat in step 1 only breaks the bonds after combustion. That leaves me with a lot of free carbon. Is heat my only option? $\endgroup$
    – JBH
    Dec 17, 2017 at 9:24
  • $\begingroup$ @JBH: What is the difference between a process and a technology? Especially in the chemical industry where this question is firmly placed? $\endgroup$
    – AlexP
    Dec 17, 2017 at 9:28
  • 1
    $\begingroup$ @JBH, mind I never used the term combustion. And if I had a more detailed description for the above, I would file it to a patent office, not to WorldBuilding... $\endgroup$
    – L.Dutch
    Dec 17, 2017 at 9:47
  • $\begingroup$ @JBH Fire only breaks bonds. It doesn't alter the molecules. The amount of carbon you get out, would be equal to what you put in, which you would want to recycle anyway since all life is based on carbon... also diamonds, plastics, petroleum, carbon fiber, so on $\endgroup$
    – Shadowzee
    Dec 18, 2017 at 4:51

@Slarty has the right idea. Some embellishments:

  • Lots of standardization of commodity items -- containers etc that allow reuse.

  • Requirement that manufacturers design products to be recycled. This can be done in various ways:

    • Devices are held together with solvent soluble connectors.
    • Conventional metal connectors.
    • Standard component materials mixes that are easily separated.
    • Use of tags in materials to facilitate rapid mechanical separation.
  • As a source of energy, use magneto/hydro dynamic fusion generators. You need to make the plasma conductive to use MHD anyway. Temps are high enough to vaporize everything. At the output end, use the equivalent of a mass spectrometer to separate ions by charge/mass ratio.


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