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For SpaceNut re #25
it is good to see you engaging with Steve on his proposal.
Out of curiosity, are you trying to improve his work?
That might be a reason for calling attention to individual parts of the proposal that don't seem to make sense to you.
Steve seems to be trying to help you to gain a better understanding of his work, but that requires your participation.
If you goal is to find every flaw without suggesting improvements, then that is different from trying to help Steve to build a solution that would past muster with a panel of experts.
Regarding the burning idea ... It is possible you missed the point of that ... the need is to burn off poisons that are mixed in the gases. That is an expenditure of energy that makes a LOT of sense to me.
If you're going to offer an alternative way to clean gas flows, the floor is yours.
However you decide to solve that particular problem, you're going to use energy.
(th)
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Carbon monoxide mixed into the ce5 which does not burn anything at all. It is colorless, odorless and tasteless gas with strong toxicity. The lowest lethal concentration of human inhalation is 5000ppm (5 minutes).
No direct entrance to the cell is required and we have multiple means to get it from the mars air.
What is needed to process is a chamber with RGSW to combine more hydrogen to form water.
https://en.wikipedia.org/wiki/Atmosphere_of_Mars
Mars Carbon monoxide is 0.0747%
https://ntrs.nasa.gov/api/citations/202 … /21-58.pdf
Global analysis and forecasts of carbon monoxide on Mars
post 8 image of gas separation just needs to have Carbon monoxide be cooled out of the incoming air same as all other gasses that are separated out.
https://ntrs.nasa.gov/api/citations/201 … 015862.pdf
Evaluation of Mars CO2 Capture and Gas Separation Technologies
https://ntrs.nasa.gov/api/citations/200 … 024956.pdf
Use different absorbents
https://ntrs.nasa.gov/api/citations/200 … 161229.pdf
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Tahanson #26
Regarding the burning idea ... It is possible you missed the point of that ... the need is to burn off poisons that are mixed in the gases. That is an expenditure of energy that makes a LOT of sense to me.
Thank you Tom, you are understanding what I am proposing.
Tahanson #26
If you're going to offer an alternative way to clean gas flows, the floor is yours. However you decide to solve that particular problem, you're going to use energy.
Correct again. If we want to remove carbon monoxide by using compression and cooling (fractional distillation), we are going to consume energy. This requires the use of mechanical devices that will eventually wear out. This results in a larger payload sent from Earth. When the mechanical systems wear out, more shipments from Earth are required to replace the worn out equipment. Or at the very least, replace worn out parts.
What I have it mind is to limit the required shipments from Earth by using hardware that is simple enough to be made on Mars. (Create a system that can be made from in situ resources). What I am proposing is cleaning "raw" air from the Martian atmosphere, by simply pumping it directly into a flame/burner in a Cell.
This is what I said:
In Post #10 of my proposal I said:
So to answer the question:
"How can nitrogen from the Martian atmosphere be brought into a base?". The answer is to simply pump outside air in from the Martian atmosphere into burning methane. Over time this will cause the percentage of nitrogen in a Cell to increase. No additional pumps, refrigeration devices, fractional distillation, or any other mechanical devices that consume energy are needed.
Thank you Tom for taking the time to read through my proposal. I know it's a lot of reading, but you've manage to understand what it is I'm trying to get across. I appreciate your efforts and taking the time to read through my proposal.
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The following are answers to question on a proposal that I posted on this forum. My proposal can be found at the following link:
Proposal: Storing Energy, Introducing a "Cell", a Soil Factory on Marsl
I've gone through some of the comments on this thread and have tried to extracted out some of the questions. I paraphrased the questions into a different sentence, while keeping the topic of the question the same. I then sorted the questions into an order that makes it easier for me to explain/answer. I plan to post questions with the answers over the next several days as time permits. Bear with me, it's going to take a little time for me to make drawings/diagrams to help answer the questions.
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Question and Answers:
You mentioned burning methane to help heat a Cell. Is this burning methane vented to the outside, or is it running inside of a Cell without ventilation?
Editors Note: A Cell is a growing area for plants and is explained in Post #6 of my proposal.
Post #6 My Proposal of a "Cell"
Methane is being reacted with oxygen inside of a Cell. Sometimes it is burned, sometimes it is ran through a CE5 (ClearEdge5) that reacts methane with oxygen without burning it. In both cases, the resulting gases are vented back into the Cell. There is not any ventilation back out to the Martian atmosphere.
The burner is enclosed inside of a metal (fireproof) container so that it is safe to have a flame inside of a Cell. The "absorption dehumidifier" that I proposed in Post #11 of my proposal, also has methane burning inside of it. As was explained in Post #11 of my proposal, it works much like an absorption refrigerator inside of an RV/camper.
Absorption refrigerators in an RV/camper run on propane and have a flame somewhere inside of the refrigerator. Many RV/campers are made from fiberglass, which is highly flammable, and much of the contents inside an RV/camper are equally flammable. Yet these absorption refrigerators are able to burn propane safely inside the RV/camper. Therefore burning methane in a Cell does not present a fire hazard.
Absorption refrigerators in an RV/camper are vented to the outside. They are not consuming oxygen from inside of an RV/camper. Instead, the oxygen comes from the outside and the exhaust is vented back outside.
A Cell is different. A burner (gas furnace) or "absorption dehumidifier" safely burns methane in a Cell, consuming oxygen in the Cell. (This is how oxygen is removed from a Cell). Exhaust is vented directly back into the Cell. No water, CO2, or heat is lost to the Martian atmosphere by doing it this way. And yes, we do need to consider what's coming out of a burner, as the exhaust is vented back into the Cell.
Keep in mind that a Cell is a growing area for plants, not a living area for humans. As long as the air quality of a Cell is good enough for plants to survive, then the Cell will work as described.
Regardless of whether methane is being burned, or if it is ran through a CE5 which does not burn methane, either way, when methane reacts with oxygen, it only creates two things: CO2 and water, as shown in the equation below.
Methane, which is stored outside of a Cell, is piped into a Cell much like natural gas is piped into a home or building. As was just stated, when methane reacts with oxygen in a Cell, it only creates two things: CO2 and water, and plants need both.
Both the CO2 and water are vented back into the Cell, and therefore stays in the Cell. None of the CO2, water, or heat is lost by doing it this way. Any impurities that are in the air of a Cell also end up passing through a methane flame. When impurities pass through burning methane in the presence of oxygen, they are burned off as was explained in Post #10 of my proposal.
Post #10 How the Martian Atmosphere is Brought into a Cell
Burning methane cleans the air in a Cell
The assumption is that the gases will burn off and be reduced into something harmless, such as CO2, water, etc. Or, if it doesn't react, then it must be fairly inert. Thus the burning of methane in a Cell cleans the air, enabling various processes to take place in a Cell.
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Question and Answers:
I don't like the idea of having a furnace that puts CO2 and heat back into a room, there are reasons why we don't do that in homes on Earth.
Actually there are three reasons why we don't do that in homes on Earth. One of those reasons is carbon monoxide (CO), another reason is nitrogen dioxide (NO2), and the third reason has to do with impurities found in natural gas. I'll discuss each of these things separately.
First, carbon monoxide:
Carbon Monoxide
Carbon monoxide is the result of incomplete combustion. As long as the combustion of burning methane is complete, there will not be any carbon monoxide created.
WikiDoc article Carbon monoxide states:
Carbon monoxide is produced from the partial combustion of carbon-containing compounds, notably in internal-combustion engines. Carbon monoxide forms in preference to the more usual carbon dioxide when there is a reduced availability of oxygen present during the combustion process.
Methane has incomplete combustion when there is not enough oxygen available to react with the methane. In my proposal (Post #14) I did mention that the oxygen level in a Cell is adjustable.
This is what I said:
Post #14 How much oxygen does a Cell produce?
How much methane does a Cell require?
It should be noted that the percentage of oxygen in a Cell is adjustable. The Oxygen Control System has oxygen sensors in the Cell. It is able to keep the percentage of oxygen in the Cell at a preset value. If the Oxygen Control System has an oxygen level set at 21% (similar to Earth), then as long as enough methane is reacted with oxygen, the percentage of oxygen in the Cell will remain constant at 21%. If the oxygen setting is changed to 25%, the Oxygen Control System can react less methane with oxygen, which will allow the percentage of oxygen in the Cell to slowly increase. After the oxygen level reaches the desired setting of 25%, the Oxygen Control System removes oxygen at the same rate it is being produced, which will hold the percentage of oxygen constant at 25%.
If need be, the level of oxygen in a Cell can be turned up in order to ensure complete combustion of methane. This coupled with having high quality burners, should alleviate any problem with incomplete combustion, which in turn alleviates any problem with carbon monoxide.
As I mentioned in my proposal, burning methane in a Cell cleans the air in the Cell. If some carbon monoxide were to be present in a Cell, it would float around the Cell until it passed through burning methane. When it passes through burning methane in the presence of oxygen, it will pick up an extra oxygen atom and be converted into carbon dioxide.
It doesn't take that high of a temperature to get carbon monoxide to react with oxygen. This is how catalytic converter's work in automobiles. Methane burns at a temperature of 3,542 F (1,950 C). This is plenty hot enough to get carbon monoxide to react with oxygen.
If need be, a catalytic converter could be added to the exhaust of a burner. The hot exhaust coming from the burner would pass through the catalytic converter before entering the Cell. The problem with this approach is that it adds complexity to the system. More supplies (catalytic converters) would have to be sent from Earth. I don't think catalytic converters will be needed, but it is an option if the need arises.
Because burning methane converts carbon monoxide into carbon dioxide, it provides a way of pumping raw air from the Martian atmosphere directly into a Cell without any additional processing. When outside air is brought into a Cell in this manner, I refer to the air coming in as "Cheat".
Air in the Martian atmosphere contains a small amount of carbon monoxide and is not processed in anyway. Carbon monoxide and any other impurities are burned off by pumping the air directly into burning methane.
Keep in mind that a Cell is a growing area for plants, not a living area for humans. As stated in my proposal (Post #7), any humans working in a Cell must be wearing breathing apparatus. As long as the air quality of a Cell is good enough for plants to survive, then the Cell will work as described.
With good quality burners being used, and the oxygen level being adjustable, and burners constantly cleaning the air, carbon monoxide in a Cell is a not an issue.
Nitrogen Dioxide
Another potential problem is the presence of nitrogen dioxide (NO2). How much nitrogen dioxide is created is dependent on a number of factors, including the air pressure and the percentage of nitrogen in the Cell, both of which are adjustable.
Although breathing nitrogen dioxide (NO2) over long periods time can cause respiratory problems in humans, it turns out that nitrogen dioxide (NO2) in the air can help plants to grow. As I explained in my proposal, a Cell is a growing area for plants, not a living area for humans. Humans must wear breathing apparatus when working in a Cell (Post #7).
Article: Nitrogen dioxide is a positive regulator of plant growth
Exposing plants that are well supplied with soil nitrogen to gaseous NO2 increases the uptake of nutrients, photosynthesis, and nutrient metabolism so that shoot biomass, total leaf area, and the contents per shoot of C, N, P, K, Ca, Mg, and S (or Fe), free amino acids and crude proteins approximately double over those of control plants, with some exceptions (Table 1). Fruit yield is also increased 1.4-fold compared with control plants (Table 1). An increase in photosynthetic rate under the influence of NO2 has also been reported by Xu et al.
In my proposal, methane gas is not burned in living areas for humans. It is only burned in a Cell.
As long as the plants and soil are both healthy, not only will nitrogen dioxide (NO2) not harm plants, it will actually help them to grow. Therefore, having small amounts of nitrogen dioxide in a Cell is not an issue.
How much nitrogen dioxide is in the air at any given time is dependent on how fast it is created verses how fast it is consumed. How fast it is consumed is dependent on a lot of things, including the number of plants in a Cell compared to the size of the Cell, the percentage of nitrogen in the air, the amount of soil that is in the Cell, and on soil structure.
I introduced several metrics in Post #15 of my proposal. Some of these metrics would effect, or be effected by, the amount of nitrogen dioxide in the air.
In Post #15 I introduced the metrics "Ratio of area of plants to area of building" (Metric #2), "Percentage of soil per unit of volume" (Metric #3), and "Amount of food produced per unit of volume" (Metric #4). The metric for the amount of food produced could be increased by having a small amount of nitrogen dioxide in the air.
Both carbon monoxide (CO) and nitrogen dioxide (NO2) can be reduced by using high quality burners. I do not see carbon monoxide (CO) or nitrogen dioxide (NO2) being an issue in a Cell. However, we do need to consider impurities in natural gas.
Impurities in natural gas
The third reason we don't burn natural gas inside of homes on Earth is because of the impurities in natural gas. On Earth, natural gas is mostly methane, but it isn't 100% pure methane (CH4). According to the link below, the methane content of natural gas on Earth can be as little as 65%.
On Earth, natural gas contains many impurities. Many of the problems associated with burning natural gas in homes has to do with the impurities in natural gas.
From PennState College: Natural Gas Composition and Specifications
Raw natural gas also contains water vapor, hydrogen sulfide (H2S), carbon dioxide, nitrogen, helium, and other impurities, such as mercury. Table 12.3 gives some examples of the composition of natural gas produced in three different locations, to give an example that methane content of natural gas can be as low as 65%.
On Mars, methane made from the Sabatier process does not contain hydrogen sulfide (H2S), nitrogen, helium, mercury, and other harmful impurities found in natural gas on Earth. Therefore burning methane created by a Sabatier reactor does not create the toxins that are created when burning natural gas in homes on Earth.
Although not mentioned in the quote above, natural gas on Earth also contains benzene, which is a problem.
Wikipedia article Benzene states:
Benzene is a natural constituent of petroleum and is one of the elementary petrochemicals. Due to the cyclic continuous pi bonds between the carbon atoms, benzene is classed as an aromatic hydrocarbon. Benzene is a colorless and highly flammable liquid with a sweet smell, and is partially responsible for the aroma of gasoline.
Article: Gas Stoves Leak Dangerous Benzene, Study Says, But You Can Reduce Your Exposure
New research has found that natural gas stoves leak harmful chemicals, even when turned off. The study, published yesterday in the journal Environmental Science & Technology, confirmed previous findings that the fuel used to power gas ovens, stoves, ranges, and water heaters contains dangerous contaminants that have adverse health effects for adults and kids.
Article: Gas stoves pollute homes with benzene, which is linked to cancer
What can you do about gas stove pollution?
Gas utilities have long researched how gas stoves pollute indoor air and even developed new styles of burners that use less gas and emit less nitrogen dioxide. But manufacturers don't use them, saying they are more expensive, harder to clean and consumers aren't demanding them.
High quality burners will be used on Mars, and methane produced on Mars will not have the impurities found in natural gas on Earth. Therefore I don't see the problems with impurities found in natural gas on Earth being a problem with methane create from a Sabatier reactor on Mars.
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Question and Answers:
Is there any kind of balancing, or matching, that has to be done in this proposal?
There isn't anything that needs "balanced" in the first part of my proposal (Post #1 through Post #5). In those posts, I introduced something I call the "Methane-Oxygen Cycle", and I talk about energy storage.
However, when I introduced a Cell in Post #6, and start moving forward from there with more processes and control systems, then there are a number of things that need balanced, because these processes work together as a single system. I think the longer someone studies my proposal, the more they'll realize the required balancing is very forgiving.
I didn't say a whole lot about balancing in my proposal. If I did my proposal would be more than twice as long. As it is, my proposal is already about 90 to 95 pages long in a PDF format. I felt like it was already too long for someone to read and take in at one time.
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A lot of materials there, looks like a lot of work. I am a little compromised as to not seek stress just now for a medical concern. But if I get a chance.........Looks like a lot of work.
Done
I am starting to ask seriously "Why do I do this?"
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Hey Void, thanks for checking in. Hopefully you'll find time to read through my proposal at some point, then tell me what you think.
Yes it's a bit of work. This is an idea had 25+ years ago. I'm not posting this proposal to develop anything, rather I'm trying to share a set of ideas that I already have, dating back to the 1990's. I think you'll find this set of ideas all fit together as a single system. I've got a lot more things I plan to post over the next several days. I finished the last of my drawings/images last weekend. Each day I'm attempting to review my verbiage, which I had already written, that goes with the drawings/images, then put up a post each day. I work 50+ hours a week and try to review 1 post a day during my lunch break. Things don't always go as planned.
Hopefully you can continue to hang out with me as I post more stuff. Hopefully an image will start to appear of what I have in mind. There is a heck of a lot of reading, I know, and more to come. I can't help that. No one said a Martian base would be simple. Feel free to ask questions. I may not answer them right away, but I WILL get to them eventually. The more people I can get to read through all this the better. (I hope I didn't give you a heart attack! Lol).
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Question and Answers:
In post#10 of your proposal, you show outside air from the Martian atmosphere being pumped into a Cell. You cannot use that air because it is toxic to plants.
The main reason air in the Martian atmosphere is toxic, is because of carbon monoxide. As I explained in Post #10 of my proposal, carbon monoxide is converted into carbon dioxide as it comes into a Cell. Therefore carbon monoxide in the Martian atmosphere is not a problem. However, there can be other toxic things in the Martian atmosphere that I did not mention in my proposal.
For example, sometimes the Martian atmosphere contains trace amounts of methane gas. Mars tends to burp up methane gas every once in a while. At this writing the source of Martian methane is not known. It could be from geological processes taking place somewhere in the Martian crust. Or it could be produced by Martian life (microbes) living somewhere beneath the surface.
Wikipedia article Natural methane on Mars
The first evidence of methane in the atmosphere was measured by ESA's Mars Express orbiter with an instrument called the Planetary Fourier Spectrometer.
...
This spatial and temporal variability of the gas suggests that the methane was locally concentrated and probably seasonal. It is estimated that Mars produces 270 tons of methane per year.
The article also states:
On 7 June 2018, NASA announced the confirmation of a cyclical seasonal variation in the background level of atmospheric methane. The largest concentration of methane detected in situ by the Curiosity rover showed a spike to 21 ppbv, during an event in late June 2019.
It's possible that an underground habitat on Mars could experience a "problem" with methane seeping into the habitat the same way some mines on Earth have a problem with methane seeping in, (especially coal mines). In my proposal, any methane that ends up in a Cell will be burned off and converted into CO2 and water.
Methane, or any other toxins in the Martian atmosphere coming in as Cheat, will be burned off. (In Post #10 of my proposal I describe outside air being pumped directly into a flame in a Cell as "Cheat".) The ability to "steal" methane from the Martian atmosphere can be of great benefit to a Cell, and to a Martian base.
I think it's fair to say a Martian base can always use more water. There is plenty of oxygen on Mars to produce water, however it is the hydrogen that is in short supply. Each molecule of methane contains four atoms of hydrogen (CH4). The ability to "steal" methane from the Martian surface would give a Martian base a small boost in hydrogen, which in turn would give a base in a small boost in water.
Other than methane and carbon monoxide, there are other harmful impurities that could end up in the Martian atmosphere, and as a result end up in a Cell. For example, a comet hitting Mars could add harmful impurities to the Martian atmosphere.
There have been many proposals about sending comets (dirty snowballs) crashing into Mars in order to bring water to Mars. Those dirty snowballs would not only bring water to Mars, they would also bring methane, which would help thicken the Martian atmosphere, increasing atmospheric pressure. And methane would also help warm the planet, as methane is more than 25 times as potent than CO2 as a greenhouse gas. Comets would also bring other frozen gases to Mars, such as cyanide, which are not often mentioned.
In 1910 Halley's Comet made an unusually close pass by Earth, making it clearly visible without the use of binoculars or a telescope. Camille Flammarion, a French astronomer, discovered Halley's Comet contained cyanide, which created a panic.
Article: The End of the World in 1910—Halley’s Comet
by Susan G MathisIn February 1910, astronomers announced that the Earth would pass through the cyanogen-laced tail of Halley’s Comet. Poisonous gas, Cyanide, would snuff out all life and end the world as they knew it on May 19, 1910!
The New York Times ran the story of the French astronomer Camille Flammarion’s theory which reported that poisonous gas, Cyanide, would snuff out all life and destroy the earth! Most astronomers in the scientific community rejected this theory but thanks to this article, the frenzy had begun.
Wikipedia article Halley's Comet
The 1910 approach, which came into naked-eye view around 10 April and came to perihelion on 20 April...
...
...the comet made a relatively close approach of 0.15 au, making it a spectacular sight.
Indeed, on 19 May, Earth actually passed through the tail of the comet. One of the substances discovered in the tail by spectroscopic analysis was the toxic gas cyanogen, which led astronomer Camille Flammarion to claim that, when Earth passed through the tail, the gas "would impregnate the atmosphere and possibly snuff out all life on the planet." His pronouncement led to panicked buying of gas masks and quack "anti-comet pills" and "anti-comet umbrellas" by the public.
Below are pictures of Hally's Comet taken in 1910. Because Hally's Comet made a relatively close pass by Earth it was clearly visible in the sky.
1910 picture of Hally's Comet over Gary Indiana. (Southeast part of Chicago)
1910 picture of Hally's Comet over El Paso
Picture of Hally's Comet from the Library of Congress
If a comet (or comets), striking Mars caused methane, cyanide, and other gases to be released into the Martian atmosphere, these gases would end up coming into a Cell through Cheat and would be burned off.
Someday, if it were ever to start raining on Mars, Martin soil could release gases as I mentioned in Post #10 of my proposal. My proposal provides a defensive mechanism for dealing with toxins in the Martian atmosphere, such as those brought from comets, and (someday) gases originating from Martian soil.
This is what I said:
Quote - - - - - - - - - - - - - - - - - - - - -
Post #10 How the Martian Atmosphere is Brought into a Cell
A potential problem with making soil on Mars is that it might release gases when it first comes into contact with air and/or water. Such was of concern with Apollo 11 and lunar dust, as Buzz Aldrin described in his book "Mission to Mars".
Mission to Mars
by Buzz Aldrin
Chapter 4 Dream's of My Moon
(Page 84 in my book)Lunar dust soiled our suits and equipment, and it had a definite oder. Like burnt charcoal, or the ashes that are in a fireplace. Especially if you sprinkled a little water on them.
Before we left Earth, some alarmists considered the lunar dust as very dangerous. In fact, pyrophoric, capable of igniting spontaneously in air. The theory was that lunar dust had been so void of contact with oxygen, as soon as we re-pressurized our lunar module cabin, it might heat up, smolder, and perhaps burst into flames. At least, that was the worry of a few. A late July fireworks display on the moon was not something anyone wanted!
It's possible that a fresh tray of soil in a Cell could vent some gases. Some of these gases might be desirable and some may not.
The Case for Mars
The Plan to Settle the Red Planet and Why We Must
by Robert Zubrin
Chapter 7 Building the Base on Mars
Section: Green Thumbs for the red Planet
(Page 214 in my book)The oxidant that Viking may have detected in Martian soil will be no problem, as it decomposes into reduced material and free oxygen on contact with water. The warm greenhouses will be moist environments, and as the moisture circulates it will quickly cause the greenhouse soils to give off their oxygen.
Martian regolith also contains frozen CO2. It's possible that soil made on Mars will vent CO2, oxygen, and some wanted and unwanted gases. If fresh soil were to release gases in a Cell, these gases would end up passing through burning methane in the presence of oxygen. The assumption is that the gases will burn off and be reduced into something harmless, such as CO2, water, etc. Or, if it doesn't react, then it must be fairly inert. Thus the burning of methane in a Cell cleans the air, enabling various processes to take place in a Cell.
End quote - - - - - - - - - - - - - - - - - - - -
Conclusion
There are several sources of gases that could end up in the Martian atmosphere, and consequently end up coming into a Martian base. Methane could come from under the surface of Mars. Methane, cyanide, and other gases could appear in the Martian atmosphere anytime a comet comes into contact with Mars. Other gases could appear in the Martian atmosphere anytime oxygen and/or water comes in contact with Martian soil.
Regardless of the type of gas and its source, as stated, the assumption is that the gases will burn off and be reduced into something harmless. Or if it doesn't react, then the gas must be fairly inert.
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Thermodynamic System
I think I need to pause a moment and explain some things about a "thermodynamic system" before answering more questions. In the world of thermodynamics, it's a common practice to draw a circle around some process and refer to it as a "system". The circle drawn around a process is called a "boundary".
Anything inside of that boundary is referred to as a "system." What is going on inside of the boundary is not important. All that matters is what is going into the system and what is coming out.
Here is an example:
Source of image: Thermodynamic system and its type - Definition & Examples
Two things, mass and energy, can go into, or out of, a system by crossing the boundary. A "Closed System" is defined as energy crossing the boundary, but not mass. An "Open System" is defined as both mass and energy crossing the boundary. An "Isolated System" is defined as a system that does not have any mass or energy crossing the boundary.
Source of image: Introduction to Thermodynamics
A boundary can be placed around a large complicated "system". As an example, I made the diagram below by drawing a boundary around a coal powered plant. Mass that is going into the plant is coal and air. Mass going out of the plant is the exhaust and coal ash.
Energy going into the plant is chemical energy stored as coal and air. Energy going out of the plant is the electricity the plant is generating. What is going on inside the plant, such as the details on how electricity is being generated, is not relevant. Something that is as complicated as a power plant can be simplified by putting a boundary around it and defining it as a "system", with mass and energy crossing the boundary.
One thing to note is that the mass going into a system must equal the mass leaving the system. Otherwise the system is either gaining or losing mass. The same is true for energy. Energy going in must equal the energy going out. Otherwise the system is either gaining or losing energy.
A power plant running for 30 years cannot be constantly gaining or losing mass (or energy) for 30 years. If a diagram of a system shows a gain or loss of mass/energy, it means the diagram has not accounted for all the mass/energy going into, or out of, that system.
In the world of engineering, it's a common practice to simplify something by putting a boundary around it and only consider the mass/energy going into, or out of, that system. In my proposal I used this technique a number of times. Apparently it caused some confusion.
Below is a diagram of a Sabatier reactor. On the left is the mass going in (CO2 and water), and on the right is mass leaving the system (methane and oxygen). All the details about what is going on inside the boundary is irrelevant for the sake of my proposal. What is important is that the system is balanced, meaning that the mass going into the system must equal the mass leaving the system. And the energy going into the system must be equal to the energy leaving the system.
In the drawing above, mass going into the system has the same number of atoms as the mass going out of the system. Therefore the system is balanced as far as mass is concerned.
The atoms going out of the system are arranged differently than they were when entering the system. It takes energy in order for the mass to change forms. Therefore the system must be given a supply of energy, which is shown going into the system in the form of electricity.
The electrical energy going into the system must be equal to the energy leaving the system. Energy is leaving the system in the form of chemical energy. That is to say, the mass leaving the system (methane and oxygen), contains more chemical energy than the mass that came into the system (CO2 and water). It took energy to rearrange the mass coming into the system into the form that is leaving the system.
In the drawing above, the amount of mass going into the system is equal to the amount of mass leaving the system. The amount of energy, in the form of electricity, is equal to the amount of energy leaving the system, in the form of chemical energy. Therefore the system shown is balanced.
Searchterm: thermodynamics
Last edited by Steve Stewart (2023-10-03 07:48:46)
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post #36 is an open loop system if anything from the outside is brought inside for use.
Co2 above 1000 ppm is toxic by itself in a 14.7 psi earth atmosphere.
Yes we know that co is poisonous. Any atmospheric compounds of these put into a fueled chamber does not change them with out a catalyst to cause the atmosphere to break specific elect compounds at given temperatures. That is what MOXIE does with just 300 w at 800 c inside each basically a fuel cell in reverse after pressurizing it from mars levels to allow it to function.
There is also heat that is energy from burning and while mars air is cold the compression will cause heat as well. Not to mention to change the burn means more energy on the input to filter the air and concentrate what we desire for a better burn to which providing more co2 or co is not going to improve that tweaked burn condition. Do not forget that increase of the chamber temperature before exhausting will cause internal pressures to rise. It's one of the reasons that my 2.5 l boxer engines fail.
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Question and Answers:
Post indicates burning fuel with oxygen but leaves with requiring more collection from the vacuum pump for co2 to make oxygen for it to create heat. That exhaust means we need a capture system rather than sending it not the cell or for wasting it.
I'm trying my best to understand this question/statement. I think the question is stating that the Martian atmosphere, which is mostly CO2, is brought into a Cell. The CO2 is then converted into oxygen by plants. The oxygen is then used to react with methane. That much is true.
However, the rest of the question seems to imply that the resulting CO2 is vented back out into the Martian atmosphere, which would waste heat and require more air from the Martian atmosphere to be brought into the Cell to maintain air pressure.
That's not how the system works. Regardless of how methane is reacted with oxygen (burning or CE5), in both cases the reactions consume oxygen from the air in a Cell and release CO2 and water back into the Cell.
Air from the Martian atmosphere is brought into a Cell by pumping it directly into burning methane (I call the incoming air "Cheat." See Post #10). From there most of the CO2 is converted into oxygen by plants, and some CO2 is removed by the Air Pressure Control System (Post #12) whenever the air pressure gets too high.
Once the CO2 is converted to oxygen by plants, some of the oxygen is used when methane reacts with oxygen (May or may not be burned). Some oxygen is removed from the Cell where it is available for use elsewhere in the Martian base (Post #7).
When oxygen reacts with methane it produces CO2 and water. Both the CO2 and water are kept in the Cell. The CO2 then cycles back again, where it can be converted into oxygen, or removed by the Air Pressure Control System, which prevents the air pressure from going above a preset value.
The diagram below shows a couple of processes going on in a Cell. By no means does this diagram show all processes of a Cell. It only shows two processes out of many. Some of the CO2 in a Cell is being consumed by plants and is converted into oxygen, which is released into the air of a Cell.
Methane reacts with oxygen. Sometimes it is burned and sometimes it is ran through a CE5. In both cases the reaction releases CO2 and water. The water is picked up by the dehumidifier and could be used to water plants.
CO2 resulting from reacting methane with oxygen is released back into the air of a Cell. Some of this CO2 is used by plants and is converted to oxygen, and the cycle repeats, as indicated below.
Most of the CO2 that is consumed by plants is coming from the reaction of methane and oxygen, and is not coming from the Martian atmosphere. (Although some CO2 is coming into the Cell through Cheat). Most of the oxygen being reacted with methane is oxygen produced by plants.
A Cell is not a closed loop system, because mass (and energy) are entering and exiting the loop (crossing a boundary). Therefore a Cell cannot be classified as "closed loop", but perhaps it could be thought of as a "mostly-closed" loop system.
CO2 and water are consumed by plants, producing oxygen. Methane consumes oxygen and produces CO2 and water, where is can be used by plants. From this prospective, the cycle could be thought of as being "mostly-closed loop", as shown in the diagram above.
To repeat: Reacting methane consumes oxygen and releases CO2 and water. Plants consume CO2 and water, releasing oxygen. However this is NOT a closed loop because water, oxygen, and CO2 are allowed to enter and exit the loop (cross a boundary), making the cycle open loop.
Other things to note:
Air from the Martian atmosphere (Cheat) is only brought into a Cell when methane is being burned. A CE5 does not burn methane, and therefore it does not provide a way of bringing in Cheat. If a CE5 were the only thing running in a Cell, then there would not be any air being brought in from the Martian atmosphere.
As I mentioned in my proposal, there are pro's and con's to each of the devices that use methane (burner, engine, CE5). The advantage of burning methane is that it enables Cheat. That is, it provides a way of bringing in air from the Martian atmosphere. The advantage of a CE5 is that it converts methane and oxygen into electricity, the disadvantage is that it does not enable Cheat. That is, air from the Martian atmosphere is never brought in through a CE5, it is only brought in when methane is being burned.
Another thing to note is that air from the Martian atmosphere is brought into a Cell independently of the air pressure of that Cell. Air is not brought into a Cell in order to increase air pressure, the Air Pressure Control System takes care of that. To say again, air is brought into a Cell whenever methane is being burned and is independent of the air pressure in a Cell.
Let me repeat: It doesn't matter if the air pressure in a Cell is going up or down. If methane is being burned, then air from the Martian atmosphere comes in. If there isn't any methane being burned, then there isn't any air from the Martian atmosphere coming in.
The Air Pressure Control System, which is simple in design and can be built on Mars, will keep the air pressure in a Cell at a preset level. There are a number of processes in a Cell than can cause the air pressure to increase. And there are a number of processes in a Cell that can cause the air pressure to go down. Either way it doesn't matter. The Air Pressure Control System will hold the air pressure constant.
As a general rule, air coming into a Cell as Cheat tends to increase the air pressure of the Cell. The Air Pressure Control System removes pure CO2 from the air to hold the air pressure at a preset value. Air from the Martian atmosphere coming into a Cell and pure CO2 leaving the Cell causes the percentage of other gases coming in to increase. (Such as nitrogen coming in and not going out. This causes the percentage of nitrogen in the Cell to increase).
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repost
On the subject of the amount of area required to feed one person, SpaceNut (post#646) posted the article:
Could We Turn Mars Green Sooner Than Expected?
Which states "It takes around 370 square metres to feed a single person on a vegetarian diet."
The (tentative) plan for Artemis 3 is to land two astronauts on the surface of the Moon and stay for about one week (subject to change). If a crew of two were to have an extended stay on the Moon and only eat what is grown on the Moon, it would require a growing area that is 740 square meters in size (about 8,000 square feet). (Based on SpaceNuts post of 370 square meters per person).
One thing to keep in mind, is that humans do not produce enough CO2 for a garden that is big enough to feed themselves. In other words, two astronauts on the Moon will not breath out enough CO2 that a 740 square meter garden would consume. Eventually the plants will die due to a lack of CO2, or the astronauts will die due to starvation. Bryce Meyer has pointed this out a number of times, including in the following YouTube videos. (2nd point below).
Image above is from YouTube video:
Mr. Bryce Meyer: Space Farming, Menus, and Biological Life Support: For Here and There
Image is at 24m 25s into the video.In the following YouTube video, Bryce explains why humans cannot exhale enough CO2 to feed themselves:
Video: NSS Space Forum -Bryce Myer - Farming in Space for Future Space Settlement
At 16m 50s
"Here is the problem. You do not exhale enough carbon dioxide to feed yourself."At 17m 48s
"The CO2 required to produce enough calories for you is 1.5 times the CO2 from your breath."Using the image above, Bryce explains why this is true.
On Mars this isn't an issue because there is plenty of CO2 in the Martian atmosphere. The Moon does not have an atmosphere, so on the Moon, finding CO2 for plants is an issue.
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We need to keep in mind when using the mars atmosphere directly.
The difference is earths pressure for the percentage to compare with mars.
0.0004 x 14.7 psi=0.00588
0.95 x 0.088 psi= 0.0836
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