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Here is a theoritical life support system (biological based). All feedback is welcome.
Assumptions:
green house will be used to reclaim/recycle all grey water.
There should be at least two degrees of separation between the grey water and a food source.
The green house will consume CO2 and produce O2.
There is too much radiation on the surface of Mars to grow plants. Thus all lighting will be artificial.
The atmosphere of Mars is too thin to grow plants. Thus the green houses will be pressurized and artificial air circulation will be provided.
CO2 will be filtered out of other compartments to enrich the atmosphere of the green house.
Overview of processes:
Grey-water: to swamp, to fish pond until evaporated.
Human waste: to human waste compost pile, to swamp soil, to non-edible plants soil, to non-human compost pile, to edible plants.
Non-human waste: to non-human compost pile, to edible plants.
Animal wastes: to non-human compost pile, to edible plants
Animal parts: same as human waste.
Humidity: recovered from air, sterilized, treated and stored as potable water.
to do's:
figure power consumption
figure water requirements
figure space (area) requirements
determine testing equipment
determine process checkpoint locations (telemetry)
Plants:
--edible:
----all your favorite vegies
--input:
----Watered from potable water supplies.
----Light from green house lamps
----Air circulation by fans
----CO2 from humans and animals
----worms
----soil
----seeds
--Output:
----food
----used soil to compost pile non-human
----seeds
--processes:
----till soil
----plant crops
----water plants
----harvest crops
----after 2 crops, recycle soil to compost pile non-human
----separate tools for edible and non-edible green houses, to prevent cross contamination.
----O2 removal
----CO2 injection
----IMPORTANT: a portion of each crop must be allowed to produce seeds
--failure mode:
----plants become diseased, sterilize, sterilize. All soil and water go to compost pile human.
----mechanical failure, plants die due to lack of heat, O2, CO2, light, and/or air circulation. Replant or recycle to non-human compost pile.
----loss of pressure. Fix problem. Replant or recycle to non-human compost pile.
----food output is too low. Improve air circulation, watering, and lighting, refresh soil, test soil for proper nutrients, test air for proper gases. Build another green house.
----no seeds are produced. Import more seeds from Earth.
--non-edible:
----clover - fixes nitrogen, feeds rabbits, goats
----alfalfa - fixes nitrogen, feeds rabbits, chickens, goats
----grasses - removes carbon, feeds rabbits, goats
----non-human-edible plant parts are feed for rabbits, chickens, and goats.
----watered by treated grey-water
--input:
----Watered from grey-water supplies.
----Light from green house lamps
----Air circulation by fans
----CO2 from humans and animals
----soil from human compost pile
----seed
--Output:
----food for animals
----used soil to compost pile non-human
----seeds
--processes:
----same as edible plants
--failure modes:
----same as edible plants
compost pile non-human (batch process):
--input:
----animal wastes
----inedible plant mass.
----treated grey-water for moisture
----O2
----Worms
----aerobic bacteria
--output:
----Soil to edible plants
----Heat to heat sink or by air to other modules
----Methane, captured for other processes
----Humidity
--processes:
----aerate
----remove excess worms, feed to fish
----completed batch goes to edible plant green house
--failure modes:
----batch becomes diseased, sterilize, sterilize. All soil and water go to compost pile human.
----mechanical failure, batch dies due to lack of heat, O2, light, and/or air circulation. recycle to human compost pile.
Compost pile human (batch process):
--input
----Animal parts.
----human wastes
----water as needed
----anaerobic bacteria
--output:
----swamp soil
----methane
----heat
--processes:
----assemble batch process
----monitor until completion
--failure mode:
----batch failure. Sterilize. Send through process to break in to element components.
----mechanical failure, batch dies due to lack of heat. Recycle to human compost pile.
----loss of pressure. Fix problem. Restart batch.
swamp:
--input:
----grey-water
----Light
----Heat
----grasses (looks like someone will have to mow the lawn)
----Fish do NOT live in the swamp
----snails
----soil from human compost pile
----O2
--output:
----Treated grey-water
----inedible plant mass
----humidity
----snails to fish or non-human compost pile.
--process:
----water flows through swamp. Air is pumped through water to provide O2. Water may be recycled until acceptable quality is met, then water is allow to flow to fish pond.
----Swamp consists of at least three areas.
Here is a narrative of the process: Soil from human compost pile is added to area 1, area 2 and 3 contain dirt from non-human compost pile. Grey-water flows from area 1, into area 2 then into area 3. Soil is cleaned by growing grasses, alfalfa and clovers (as needed to control nitrogen). After a suitable amount of time, the soil in area 2 is sent to the non-human compost pile and is replace with dirt from the human compost pile. Grey-water now flows from area 2, thru area 1, to area 3. After a suitable amount of time, the soil in area3 is replaced, and the grey water flows from 3, thru area 2, into area 1. The total swamp area should be long to clean the water in a single pass. Snails are added to process to control moss.
--failure modes:
----plants become diseased, sterilize, sterilize. All soil and water go to compost pile human.
----mechanical failure, plants die due to lack of heat, O2, CO2, light, and/or air circulation. Replant or recycle to human compost pile.
----loss of pressure. Fix problem. Replant or recycle to non-human compost pile.
----Grey water is directed to wrong area. Correct problem and recycle water until water quality standards are met.
----snail die. Wait until water quality improves and reintroduce snails.
Pond (continuous process):
--input:
----treated grey-water
----light
----heat
----fish
----crayfish
----freshwater lobster
----O2
--output:
----food
----humidity
----CO2
----water for non-edible plants.
--process:
----pond water is aerated and circulated to produce healthy fish.
----Food is caught by fishing or netting.
----water quality is checked.
--failure modes:
----fish become diseased or water becomes contaminated, sterilize, sterilize. All water goes to swamp as grey-water.
----mechanical failure, fish die due to lack of heat, O2, light, and/or air/water circulation. Recycle to non-human compost pile.
----loss of pressure. Fix problem. Recycle to non-human compost pile.
Animals:
--Rabbits
--chickens
--goats
--fish
--crayfish
--fresh water lobsters
Insects:
--leaf cutter bees for pollination
--worms
--snails
Bacteria:
--Aerobic
--Anaerobic
Links:
http://www.waterrecycling.com/index.htm … /index.htm
http://www.greenhousegarden.com/Materia … erties.htm
https://www.sundancesupply.com/index2.h … ndex2.html
http://www.cropking.com/greenhouse.shtm … ouse.shtml
http://www.farmwholesale.com/panels.php … anels.php3
http://www.igcusa.com/btu/kirkcalc.html … kcalc.html
http://www.quickgrow.com/gardening_arti … index.html
http://www.hammacher.com/publish/67403. … mo=xsells#
http://www.aquaponics.com/]http://www.aquaponics.com/
automatic chicken plucker
http://www.schaferfarmsnaturalmeats.com … erman.html
livestock water requirements
http://www.ext.vt.edu/pubs/bse/442-755/ … ...L3]http
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Thank you for this detailed checklist. I will have to look at all the links you provide some time; they may be very useful references. I have a few comments:
Human waste: a small, compact processing unit could be built out of surface materials, plus pumps, that would resemble a waste processing facility. It needn't be very large for a small outpost. There are advantages to processing waste before pouring it into the "greenhouse"; it will have no disease pathogens left.
If a complicated waste processing unit is not possible, a simple one could be built. On Earth, they're called septic tanks and cesspools. But they stink, which is a big problem in a confined space like a greenhouse. A waste processing unit is needed to capture sewer gasses, if for no other reason than they are flammable and a potential energy source (or oxygen consumer).
Greenhouses on the Martian will NOT have a problem with solar flares or cosmic radiation. The Martian atmosphere provides adequate shielding from both for plants to survive. A dome will have to block ultraviolet, but that's not difficult. Greenhouses will also have two contrasting problems: loss of heat to the ground, especially a serious problem for roots, which in many species are highly temperature sensitive; and excess heating from trapped solar energy during the day.
-- RobS
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Are the methane gases that are produced lighter or heavier than oxygen. If lighter, a natural shaped tent that is pyramid shaped would make the best structure for the greenhouse if the septic or cesspools are within the structure.
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RobS: I'm glad you like the format.
>>Human waste: a small, compact processing unit could be built out of surface materials, plus pumps, that would resemble a waste processing facility. It needn't be very large for a small outpost. There are advantages to processing waste before pouring it into the "greenhouse"; it will have no disease pathogens left. <<
That type of facility is the backup. I was looking to design a biological recycling system. But, I think that the smaller the physical size of the system, the more mechanical processing that will be required.
>>... a simple one could be built. On Earth, they're called septic tanks and cesspools. But they stink, which is a big problem in a confined space like a greenhouse....<<
The first process for human wastes would be like a composting toilet or a septic tank. A septic tank would be better process for capturing the methane. Methane is good fuel source!
>>Greenhouses will also have two contrasting problems: loss of heat to the ground, especially a serious problem for roots, which in many species are highly temperature sensitive; and excess heating from trapped solar energy during the day.<<
I think this problem is easy to solve. in addition to an external heat source, excess daytime heat will be pumped into the ground using a heat pump. This will help to keep the green house warmer during the nighttime. If the ground becomes too warm, excess heat can be exhausted in the Martian atmosphere or another ground based heatsink.
SpaceNut: Hopefully, very little methane will be produced where it cannot be easly captured and used. But, I don't know which is heaver. I'll have to make sure the monitoring/control systems are able to detect and remove methane.
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Interesting.
Have you considered hydroponics?
It would eliminate a lot of soil processing, and have higher output. The downside is it would require a bit more power and maintainance to run the pumps.
"Yes, I was going to give this astronaut selection my best shot, I was determined when the NASA proctologist looked up my ass, he would see pipes so dazzling he would ask the nurse to get his sunglasses."
---Shuttle Astronaut Mike Mullane
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Commodore: Yes, I have considered hydroponics. But, I was looking for a way to recycle the plant and animal solids. Hydroponics would be in addition to this equipment.
As an add-on. I figure that a 4'x16' (4 - 4' tubes long x 4 tubes wide, 40 watts each) hydroponics lit 24 hrs/day will require about 1KW of electrical power.
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Your plan for growing plants on mars does not address the problems with martian regolith itself since it's likely to contain oxidizers, salts, and metals that you don't want to expose to your plants.
Also, you will need a lot of fertilizer for your plants...nitrogen.
There very likely is no moss on mars so I don't think you are going to need snails to control it's growth in your swamp.
Some plants do not need bee's to assist in reproduction. A wind generator would be sufficient for them.
A clear dome would provide adequate light to grow plants. This also reduces your energy requirement vs providing complete artificial lighting. Why would you not wish to use it?
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Dook:
>>Your plan for growing plants on mars does not address the problems with martian regolith itself since it's likely to contain oxidizers, salts, and metals that you don't want to expose to your plants.<<
Excellent catch. I agree that the Martian regolith will need some major adjustments to be acceptable to Earth plants. Hopefully, compost will address these issues. Until these are mitigated, the hydroponics and possibly soil brought from Earth will have to serve.
>>Also, you will need a lot of fertilizer for your plants...nitrogen. <<
Agreed. That is why the "meadow" plants contain clover and alfalfa, these plants fix nitrogen.
>>There very likely is no moss on mars so I don't think you are going to need snails to control it's growth in your swamp.<<
I plan to bring my own alge. It is a good way to remove nutrients from the gray water.
>>Some plants do not need bee's to assist in reproduction. A wind generator would be sufficient for them.<<
True, but not all plants are that easy. Leaf cutter bees don't sting and don't make honey, the only thing they do is gather pollen.
>>A clear dome would provide adequate light to grow plants. This also reduces your energy requirement vs providing complete artificial lighting. Why would you not wish to use it?<<
There are a number of reasons for using the artificial light.
1) The intensity of the light is about 1/4 Earth normal.
2) I have not seen any evidence that ionizing radiation isn't a problem on the surface of Mars.
3) It provides a longer growing day. More CO2 is recycled and more food is produced. I understand that plants in Alaska do very well in the 24 hr sun of summer. Truely, the green houses should only have lighting for 12 hrs, this would allow for additional output if something happened to another part of the food supply.
4) Pressure. These systems are going to have to be very large to recycle all the water. Large domes cannot easily be attached to the surface of Mars, the atmospheric pressure will generate HUGE lifting forces on a dome. So anything with seams is a potential leak. (for example: 14 psi * 1 square yard (36*36) = 18,144 Lbs/sq yd.) After subtracting for the pressure of the Martian atmosphere (1%), the pressure differential will be just short of 9 tons/sq.yd.
Thanks everyone this is great.
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Clover and alfalfa may very well fix nitrogen with the 78% nitrogen in the earth's atmosphere but mars atmosphere only has 2.7% nitrogen. This may work but how much are they going to be able to fix in the short lifetime of a plant? It is an interesting idea but I think plants that provide food for humans would be preferred.
Okay, the light intensity on mars is only 1/4 of the earth's, still why not use that?
If ionizing radiation is a problem on the surface where are you going to put your greenhouse? Underground? An above ground greenhouse is going to be difficult enough, underground is asking for too much, it increases the mission cost and greatly increases risk. And it's unnecessary.
The martian atmosphere provides enough protection. My idea is to use two or three clear domes, one inside the other, and slightly pressurize the outer dome(s) with ozone to provide another layer of protection.
Humans can simply fill sandbags (regolith bags) and cover the roof of their habitat for even more protection. And a dome can easily be secured by placing it in a natural or man made crater and filling the bottom half with regolith. This also allows you to somehow clean the regolith of dangerous oxides, metals, and salts, add fertilizer, and place water recycling tubes and heating elements into the treated regolith as you fill the bottom half of your domed greenhouse. Also reflective mylar mirrors placed around the outside can add to the light received by the above ground plants.
Sigh...we've been all through this many times. See some of the old topics.
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>>If ionizing radiation is a problem on the surface where are you going to put your greenhouse? Underground? An above ground greenhouse is going to be difficult enough, underground is asking for too much, it increases the mission cost and greatly increases risk. And it's unnecessary.
The martian atmosphere provides enough protection. My idea is to use two or three clear domes, one inside the other, and slightly pressurize the outer dome(s) with ozone to provide another layer of protection. <<
Like I said, I haven't seen any data to indicate that the surface of Mars is safe. I haven't heard of the dome-in-a-dome idea, very interesting. I'll check through some of the older threads like you suggested. Still sometimes its good to beat a dead horse.
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MARIE found radiation in orbit above mars to be 2.5 times higher than the ISS. Exposure at the surface of mars may be equal to that of the astronauts on the ISS.
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I have to agree with Dan on this.
The future of Earth (and even Colonies on Mars and the Moon) will involve populations of billions employed as food production technicians in Urban industrial farming. Vast warehouses, factories and plants devoted to the desalination of salt water or the processing of waste for use in artificial wetlands where snails and algae are produced for fertilizer, and urban multi-story supercomplexes devoted to fish farms, pigeries, dairies, and hydroponic green houses on the top floor.
The future will be worlds of compulsory social, cultural, and economic contribution. You can scream communism until the sun falls from the uinverse but social order will be built on a future of total employment in a world where every one has the right to an equal share of the benifits and responsibilities of citizenship. The sooner we realize this the better.
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I believe Dan's post is about a life support system for mars, not the earth.
The future of the earth will involve billions as food technicians who work in cities? No way.
I've never heard that snails and algea are useful as fertilizer.
There are still vast stretch's of unused land throughout the world, advanced farming techniques will make some of these areas arable. Also genetic manipulation will produce more crops, produce disease resistant crops, and increase the nutrition value. Cities will continue to expand, the worlds population will grow but the food will still come from outside.
Also, everyone does not have, or deserve to have, an equal share of the benefits. Not everyone is an Einstein or Speilberg. And more than a few people don't want to work for their share.
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I believe Dan's post is about a life support system for mars, not the earth.
The future of the earth will involve billions as food technicians who work in cities? No way.
There is only one way for the Earth Population to reach a self sustainable fifty billion. This involves full employment in the mass production of food by an urban population. This Urban Agrarian policy will be carried by the Colonists of Mars. This is the ultimate extension of the very proposal that Dan has put forward...Industrialized food production in an Urban setting.
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