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Air pollution and waste removal
jamesburbridge
Posts: 49 XPRIZE
As we continue to develop our research into solutions, one question we keep running into is what happens currently with any captured pollutant? Scrubbers produce slurries, and those on ships can release highly acidic waste water. Filter media are typically rinsed/washed, but where does the pollutant go (I'm assuming into the soil or other water sources?)
Is there a better way to remove pollution from the air? For CO2, we have the capability to capture carbon dioxide and treat it as a source of pure CO2 for numerous applications. CO2 has some value, what about other air pollution? Would a pure stream of NOx or SOx have any kind of value? Or what about rendering the resultant 'wash water' harmless?
Lots of questions in there, but I really want to get at what is possible if we push the boundaries of waste treatment.
Is there a better way to remove pollution from the air? For CO2, we have the capability to capture carbon dioxide and treat it as a source of pure CO2 for numerous applications. CO2 has some value, what about other air pollution? Would a pure stream of NOx or SOx have any kind of value? Or what about rendering the resultant 'wash water' harmless?
Lots of questions in there, but I really want to get at what is possible if we push the boundaries of waste treatment.
2
Comments
Given your expertise, we would love to hear your thoughts on James queries. Please join the discussion.
Waste pollutants are dealt with in different ways depending on the pollutants and the operator producing them. For example:
* dilute the pollutants (and flush them into the sewage system)
* flow the pollutant stream through a bed of plants that absorb pollutants
* allow bacteria or other biological entities to process the pollutants
* send them to a hazardous landfill site (which is supposed to contain them for a long time)
* add them to solid products that lock the pollutants in place (e.g. breeze blocks, concrete, tarmac)
* disassociate the molecules in a high temperature process
* use a chemical reaction and/or catalyst to neutralise the pollutant
* stick them in a sealed container and store them on a secure site.
You can probably find limitations with all of the above approaches - there seems to be no ideal, low cost, low energy, general purpose solution to emissions that contain a range of pollutant types. Some pollutants might be handled by biological approaches and others might not. Some pollutants (e.g. metals) are toxic elements that might be absorbed by a biological entity or an inert substance - but what happens to the thing that absorbed the pollutant as that then becomes more toxic?
This is indeed a great opportunity for an XPRIZE challenge.
1) Send waste streams through a series of modules, where each deals with specific types of pollutants. [?]
2) Use nanotechnology to strip out individual atoms by type and then use these pure sources of materials in different end user manufacturing processes. The ultimate recycling machine: element by element. This falls under the sector of nanotechnology/nano-robots. It has been predicted for many years that small molecular sized robots will be built that can use sources of atoms to build sophisticated (meta-)materials and structures. [We are still not there yet.] This recycling idea is the process in reverse: specific atoms are extracted from a complex waste stream. [audacious!]
Note: nanotechnology includes biological components too.
Lets us have your thoughts on an effective way to utilize NOx or SOx captured from Air Pollution.
Haven't come across anything suggesting that BC is effective at removing air pollution, but soil health is important for removal and filtering of pollution as rain seeps through the ground. Might be an area for further exploration.
The bigger question is could strategies to capture NOx and SOx and convert them into a profitable commodity create disincentives to reduce fossil fuel combustion, which are major sources of these emissions and green house gases?
Would it make a big enough dent in the emissions to make it a viable solution for air pollution? Cutting NOx and SOx from coal power plants and reducing the cost of emission control technology seems worth it, but shouldn't we be pushing for investment in cleaner sources of energy which are viable now?
Would it be a viable and realistically effective solution for NOx in the atmosphere after it has been emitted? That's like trying to suck an ocean through a straw.
Check out this article by Sarath Guttikunda in the Wire
https://thewire.in/environment/bengaluru-will-not-breathe-better-air-even-with-44000-air-purifiers
I work in agriculture, closing the loop for some of the most environmentally impacting operations. We take manure apart in a multi step process. Biological, chemical, mechanical and thermal, to move the process to zero waste. The newest component is hydrothermal oxidization, that uses heat and pressure to make water a solvent, and O2 to cause reactions/conversions. Biomass in, nitrogen solution, phosphorus with all of the nasties the process can't break down (metals) in a sand like ash, and acetic acid (vinegar) that has a bunch of applications comes out. We harvest sulfur from a different part of the process, and all of the components get recombined to make precision agriculture products. The next step is to add methane to protein production via microbial conversion. Calysta and UniBio are the main players were watching for this. Last step water polishing will be done with duckweed in closed containment. (phytoremediation).
We would love to hear your thoughts on capturing NOx or SOx from Air to reduce air pollution and creating value out of it.
Currently roughly 2/3 of the coal ash produced from power stations in the US is recycled, primarily in the production of cement ( nearly 50 million tons out of 70 - 75 million tons produced). The remainder is usually sent to lined ponds. Under the right circumstances, the material can "set up" and be structurally strong enough to support construction of new buildings. SO2 scrubbers can be arrnaged to produce calcium sulfate, which is the primary component of wall board. In Europe, wall board production is a requirement. In the US, naturally occurring calcium sulfate is usually more competitive, although some 10 - 15 million tons is utilized. That which is not used is sent to lined ponds. When the water evaporates, the resulting land is suitable for reuse. As these materials are taken from the ground, they are most likely to be returned to the ground. For example, China uses 3 billion tons/yr of coal. That produces in the neighborhood of 500 million tons/yr of ash materials. There are very few useful products that we use at the rate of 500 million tons/yr. It's not that we can't make some useful products. It's that there is too much of the stuff. The oil and gas industry recovers sulfur from natural gas and crude oil. In 1970, sulfur was worth $40/ton. Today, it is hardly worth anything. Sulfur is no longer mined and that which is "recovered" is usually reinjected into the ground. There have been many processes for recovery of sulfur to make products. Other than the gypsum products mentioned above, all of the rest have resulted in bankruptcy for the developers.
However, we both acknowledge that pollution control is not universally applied, and so then what? The long-distance dispersal of air pollution is a major focus of our research and what can be done to defend air quality from incoming pollution? There seem to be a variety of ways to capture or decompose pollution, but all struggle with efficiency given the trance amounts of pollution in the oceans of air that make up the urban air shed. Would love to get your thoughts on existing tech or natural solutions to remove or decompose pollution in ambient air.
Co2 can be a valuable commodity with compelling prospects for example feeding the planet - there is a NASA technology spin off based in Finland Finland that produces high protein yield fit for human consumption and bofc animal feed - you can find them on twitter at https://twitter.com/Solar_Foods this is what is comming out in my support network since we have ben putting this together - the process requires a high volume input of Co2 and of course this would have to be isolated from other waste flue gas biproducts such like Nox and Sox but yes Co2 captured for sequester can be a valuable commodity. Solar Foods is a recent new proposal that ties in with Kenta waste heat recapture for load balancing and a cheap profitable source of energy. They say it tastes and has a wheat like character.
Solar Foods (@Solar_Foods) | Twitter
The latest Tweets from Solar Foods (@Solar_Foods): "Electric food – the new sci-fi diet that could save our planet | @GeorgeMonbiot #FutureofFood #food # ...
twitter.com
Kenta energy storage battery for solar energy load balancing release at night and incidentally sequester of Co2 Nox and Sulphur waste treatment. Some of it would be a valuable commodity with incidental benefit potentials. This potential was alerted to me by Angela Gibson JPL ambassador - NASA Social on Twitter. There are also algea farming potential thjat may be attractive but not requiring nearly as much Co2 sequester - last but not least there is the potential use as biofeuls which would also use a quantity of captured Co2 from LNG - Coal Plants and manufacture such like cement manufacture an ominous emitter of Co2 unecessarily.
Thanks for your time........
From: Stefan Tubman
www.shwaycoms.com
Relative to the unintended consequences (ie pollination, soil nutrients, etc.), I suspect that the amount of air treated compared to the total amount of air will still be fairly small, if only because 75% of the earth's surface is water and the concentration of vehicles of any type over the world's oceans is small. However, there would still be a positive contribution.