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Pitch

A novel method for aerobic waste digestion coupled with crop growth that allows production of food and fuel from municipal waste materials.


Description

Summary

Right now, crop production and waste disposal are uncoupled.  This leads to landfill disposal or anaerobic digestion of waste materials, which in turn produces methane and other undesirable side effects.  Meanwhile, crops are grown in soil that has been depleted of its organic matter using equipment that produces carbon dioxide and other harmful emissions.  By coupling these two processes in an aerobic digester, methane production is eliminated.  Furthermore, by eliminating the use of landfills for waste disposal, soil and groundwater contamination is also eliminated.  By using an aerobic digestion process to treat the waste, the only two outputs of this system are carbon dioxide and undigested waste.  The undigested waste can be reused in further digestions.  The carbon dioxide emitted in the digestion process is recaptured by the plants growing in the waste medium.  Thus the system primarily outputs agricultural crops and crop residues.

Unlike most agricultural systems, this method of crop production appears to be extremely robust.  Practically any municipal or agricultural waste is suitable for use in the system.  Non-potable water is also acceptable for use in biofuel crop production.  Acceptable waste feedstocks include food waste, paper waste, green waste, manure, sewage, municipal solid waste, etc.  Furthermore, the coupling of crop production and waste disposal in the urban setting presents a sustainable method of producing food and fuel in close proximity to the location of use.  This is especially advantageous for food, as food produced using this method is both more flavorful and fresher than that produced by the conventional agricultural system.

Thus, in conclusion, by coupling waste disposal with crop production, many undesirable side effects of our current systems are eliminated while producing a superior agricultural product close to the location of its eventual use.


Is this proposal for a practice or a project?

Practice


What actions do you propose?

This technology already exists as a fully functional method of waste processing that does not involve a composting step.  The aerobic digester can be set up and planted with the first crop within a few minutes.  Afterwards, normal plant growth timetables apply to production of crops.

The major barrier to widespread adoption is existing policies governing waste disposal, which actually bar adoption of this method for waste disposal.  Because this method requires more than 24 hours to completely process the waste, it is not acceptable under current regulations.  It will require an extensive rethinking of regulations and systems governing waste disposal before this method can be implemented at any scale.  As an aside, after over two years of operations, existing aerobic digesters do not seem to attract either rodents or flies.  They are virtually indistinguishable from any other crop production method in terms of creating a public health issue.    There is no offensive odor associated with them and they are most certainly not just piles of trash.

Another barrier to adoption is the objection to eating food grown in waste, just because it sounds gross and disgusting.  However, in practice, the food grown in experimental aerobic waste digesters over the last two years has been exceptionally delicious.  Plants grown using this technology appear also to be much healthier than even soil-based plants grown using organic production methods.  An additional advantage to growing food plants this way is that they can be made portable, allowing for a system in which waste is collected and living produce is delivered simultaneously.  This promises to be an economical viable method for getting fresh produce anywhere that currently has waste pickup.

Because this system involves aerobic digestion, it is significantly less expensive than anaerobic digestion methods.  It is probably already cost-competitive with landfills for waste disposal.  Since it outputs primarily agricultural crops from a closed system, it is both more sustainable and better for the climate than the status quo.

Additionally, biofuel crops grown using this system avoid taking agricultural land away from food crops while taking advantage of the fact that all substrates which are not acceptable for food production are acceptable for producing biofuels.  This is because biofuels are not intended for human or animal consumption, and thus food safety rules don't apply.

By providing a method of production for biofuel crops that does not compete with food crops, and may be less expensive and less carbon intensive than current methods, this should provide a path for widespread adoption of biofuels.  As municipal waste is a large and constant feedstock, this provides a reliable and stable way for biofuel crop production.

Thus, in conclusion, this is likely to make a significant impact on both agricultural production and waste disposal.  Most importantly, it provides a method for biofuel crop production that does not compete with food crops.


Who will take these actions?

No one seems to be particularly interested in adopting this technology.  The job of completely overhauling the laws governing waste disposal is more than the proposal author can do.  Instead, the proposal author is trying to generate awareness that this technology exists and is ready to be commercialized further.


Where will these actions be taken?

This technology is suited for use anywhere.  With the recent explosion of technical advances in indoor farming, virtually anywhere in the universe is somewhere this technology could be used, as long as a steady supply of waste is available.


In addition, specify the country or countries where these actions will be taken.

United States


Country 2

No country selected


Country 3

No country selected


Country 4

No country selected


Country 5

No country selected


Impact/Benefits


What impact will these actions have on greenhouse gas emissions and/or adapting to climate change?

This technology will eliminate methane emissions from landfills.  It should also reduce carbon dioxide emissions overall by greatly simplifying the supply chain for food and fuel.  Both of these are significant sources of emissions that contribute to climate change change, so reducing/eliminating them should help mitigate the effects of climate change.


What are other key benefits?

Locally, the city of Los Angeles is looking to eliminate the landfill disposal of waste.  Many other local government entities would also like to reduce the need for landfills.  The state of California also is trying to reduce the contributions of waste disposal to climate change.  So this proposal would address many if not most of the solutions being sought to eliminate the impact of landfill disposal on climate change at the local and state level.  National impact will not be discussed as United States national climate goals appear to currently be in flux.  

Another positive aspect of this proposal is that it may increase both food security and availablity.  While the number of waste streams acceptable for use in food production is limited, food waste is certainly one of the most obvious substrate choices.  Currently, food waste is estimated to be a major source of climate changing emissions globally.  This technology has the potential to dramatically reduce both the overall amount of food waste and the climate impact of food production.


Costs/Challenges


What are the proposal’s projected costs?

It is fairly inexpensive to set up an aerobic digester, so it is probably a less expensive method of waste disposal than current methods.  There don't seem to be any negative side effects from running the existing aerobic digesters.  The major challenge is being able to legally aerobically digest most waste streams.  Additionally, as landfills and anaerobic digesters are established players in this field, they are likely to oppose technology that makes them financially unviable.  It is also a big challenge to find funding agencies willing to finance developing this technology.  Neither government agencies nor private business has been willing to consider funding this project.  Technology development has been bootstrapped from the ground up (the initial aerobic digesters were built from materials available for free as "trash").  Everyone seems so focused on much more trendy methods of addressing the problems of food waste, waste disposal and biofuel production that this technology is overlooked or dismissed as insignificant.  However, it appears to hold great promise for rapidly effecting a major transformation of both agricultural production and waste disposal.

 

Please note that aerobic digestion technology, as described in this proposal, is not a type of composting and should not be confused with composting.  It is something completely different.  Informally, in discussion with those involved in commercial composting, the commercial composting process has an upper limit on the amount of food waste that can be accepted which is far lower than the current availability of food waste.  This method can accommodate significantly greater amounts of food waste than the upper limit for composting.  Additionally, this method can use materials that are not acceptable for composting, such as dairy, meat, bone, fat, oil, municipal solid waste, plastics, rocks, fecal matter (including dog and cat), etc.  Most of these alternative inputs are only suitable for biofuel production due to food safety issues associated with their use in crop production.


Timeline

This technology is already having an impact at the micro level.  It has eliminated 90% of our household waste from going to the landfill (the remaining 10% is not suitable for use in food production/not currently legal for aerobic digestion).  In the short-term, rapid adoption would virtually eliminate the need for landfills while enhancing urban food security and availablity.  

In the medium term, it will probably produce enough biofuels at a price point that will make fossil fuels too expensive to be economically viable.  It will also produce an agricultural revolution similar to that from the introduction of  mechanical equipment? or even the first agricultural settlements.  

In the long term, it will enable space exploration and settlement by providing a sustainable method for producing food from waste.  Freed of the need to bring an entire trip worth of food on each mission, humans can venture farther from Earth while still enjoying fresh produce and grains grown wherever we as a species choose to live.


About the author(s)

There is one author who contributed to this proposal.  This author is trained in biochemistry and genetics, but also has decades of urban farming experience.  All aerobic digestion technology was developed by this author.  Country of residence is United States.  All implementation to date was also done by this author, this is expected to continue until the technology is fully implemented.


Related Proposals

No one else is really working on anything similar.  It's not a popular field at present.


References

There really isn't any literature at present on this technology.  It is an entirely new field of study.  Everything else is for the most part accepted knowledge (e.g. that landfills produce methane).