CELSS – Part 2 – Stablizing CO2 in an Enclosed Biosphere
Tweet ThisCO2 can stabilize using portions of anaerobic, aerobic and decomposition microbiology in an enclosed eco-sphere. Adding more plants and soil in the CELSS system, Part 1, click here
Below is a view from the top of the opened CELSS system. There are three plants. Two are growing in soil (back or top of the picture) and the third in water (lower part of the picture).
Another view.
Another view looking over the water portion of the tank.
Below is a link to microscopy pictures of micro-organisms from water pictured above:
Cyanobacteria Producing Oxygen pictures, Click here
Real-time Picture Updates:
Below is a live picture of the CELSS system. Each picture is taken once an hour. Parts of the blurred picture are condensation on the glass. If there is no picture at the time, the system is being worked for updates. Please come back a bit later.
Stabilizing CO2/Gas Composition
This system has been closed since Oct 14, 2012. It is opened today, Nov. 11, 2012, for updating Firmware and adding a few new sensors. When the system was closed up, CO2 levels were over 10,000 ppm. At that time, newly installed plants were introduced. Adding more plants and soil in the CELSS system, click here. It was planned that additional plants would stabilize the CO2 levels. LED lights are cycled on for 16 hour per 24 hours instead of 12 hours. It takes time for the gas cycle to stabilize. There are several balances being achieved. They are methane, nitrate, oxygen and carbon dioxide.
The carbon dioxide cycle starts with decomposition and plant metabolizing sugars to grow. In this case, the big contributor of CO2 is decomposition. In Part 1 the Ammonium and Nitrate cycles are balanced by allowing the bacteria to colonize on the tank walls and on objects in the water. In Part 2 CO2 and O2 need to be balanced while continuing to monitor the Ammonium and Nitrate cycles.
The progression of balances are done one at a time. Each balance action needs time to grow into its container. It’s important make sure all of the biological elements are in place before going on to the next. The goals for the system are as follows:
Amonium-Nitirate Cycle (Ranges: almost 0 ppm when no obvious decay is occurring, grow a colony when a decaying operation occurs does not push the Nitrites over 5 ppm)
CO2 – O2 (Ranges: CO2: 200 to 1300 ppm cycled per day, O2: Air: between 10% to 22%: Water <10.0 mg/L)
Methane – Ozone (O3): (Ranges: TBD – I’m not there yet!!!)
Before closing up the tank for a month, the O2 in the water was around 10.5 mg/L. This is way too much dissolved O2. Four goldfish died and started to decompose. I don’t believe the fish died because of too much O2, but the temperature in the system went up to 26 to 28 C degrees. The temperature killed then; however, I have no proof of that. I will try fish again in a week. The Amonumum and Nitries in the water reached around 0.5 ppm. CO2 maintained around 10,000 ppm at night and during the day; the CO2 went down to 8900 ppm.
After 4 weeks, the CO2 level went down to 288 ppm to 2200 ppm for a day cycle and the water has around 9.5 mg/L O2. All Nitrites, Nitrates and Ammonium are 0 ppm. There is no active decaying. Below is a picture of O2 bubbling out of he algae growing in the water.
The water chemical levels at this time are all 0 ppm for Ammonium, Nitrite and Nitrate. The pH is 7.2. DO in water is 9.5 mg/L.
Water/Air Chemicals Limits
As time goes on, the limits and ranges for chemicals in the system will be determined; however, in the beginning a roadmap needs to be established to determine relationships between chemicals, animals and physical properties. This is generally done using intuition. Afterwards, quantitative assessments can break through and measure processes and functions of microbiology, chemistry and physical properties. At the present time, a process of taking the existing system, as such as it is, and allowing it to stabilize for a period of a week or so. Change only one thing in the system to see how it reacts. Allow it to re-stabilize and then change the next thing. This is not the Scientific Method . There is no guessing what the outcome will be. Just observations. No pre-assumptions. I have always thought of the Scientific Menthod as an educated guess causing often unintentional biases. Observations can be in quantitative measurements (i.e. removing water from the system changes the humidity in the air by 10 %), or in black and white instances (i.e. turn off the LEDs for 30 days and see what is left; and believe it or not, it will still grow for a while in the dark).
The process of documenting the current stabilized conditions and then changing a single factor is extremely repeatable. If you create the same stabilized system and make a single change, the result repeats. It’s like a mechanical machine made from sturdy metal. The trick is to have a stable system; not making a change while the whole system is changing from one place to another. The hard part is knowing what to measure and how to go about measuring it.
Below is an above picture shot of the water, graduated cylinder and liquid/gas data collector.
Another picture. The board measures, RH, Temperature, Water Temperature, CO2, O2, Methane, Ozone, Air pressure and Air Temperature. About 10 years ago, this single board would require a ton of equipment that would need to sit on a table the size of a conference room. It’s technology wonderful!!!
Controlling RH (Relative humidity)
High RH is a pain the butt with closed systems. The RH in an enclosed system ranges from 22% to 91 %, depending on temperature. And if the temperature in the system decreases around 10 C degrees, the RH goes through the roof. If the temperature in the closed system goes up 10 C degrees, the amount of water in the air is doubles, but the RH remains almost the same.
Pictured below are dehumidifiers used for keeping the RH down. They are thermal electric devices used for chilling salt water fish tanks. They are used in air. Every 45 minutes, they need to be turned off for 15 minutes. A clump of ice forms on the cold part of the device. The fans above help cool off the heat sinks.
Close up of ice forming on the cold side of the theermoal electric device.
CELSS project overview and description, click here
Thermal Electric Devices used for RH control, click here
Why did you decide to do this experiment? Why is it important?
What have you learned? What imputs are required in order to ‘maintain’
this system? Do you have any idea how many living organisms are present?
Would this be a good experiment to set up for HS students as a part of the carbon cycle lesson or water cycle?nitrogen cycle?
How is this different from the biosphere in Arizona? Besides human social factor of one vs many
which led to undoing!!
Why did you decide to do this experiment?
These are results from observations of an ecosystem growing into its environment. The given set of biology is not completely moved into its new home. This posting is created to give a snapshot of an ecosystem settling in. An ecosystem is never settled in.
Why is it important?
Recognizing each step of a changing ecosystems help understand where you have been. And where you are going. It’s a roadmap.
What have you learned? What inputs are required in order to ‘maintain’
this system?
There are no maintaining inputs into this system other than light and cooling. The metabolism of the living organisms generates enough heat requiring cooling. (APT) Everything in the tank works off each other. It’s important to move living organisms into a new environment slowly and give them time to adapt one step at a time. If you throw all of the key elements (whatever those may be) into a small enclosed chamber, colonies of bacteria, plants, and etc. will not be established to help balance out cycles.
Do you have any idea how many living organisms are present?
I know there are thousands of living organisms living in the tank. I’m more interested in the category of living organisms with relations to each other. There is a huge diversity of living organisms (bacteria, algae, plants, protists, fixers, sulphates and etc..) in each category. How each group of living organisms work together in symbiosis make the tank sustainable in its own cosmos. Water is the lubricant of this machine. I’m working on future postings for presenting pictures of the microbiology contained in the CELSS. And there are postings showing data trends for CO2, O2, CH4 and etc… Computers are collecting the data. It’s not done, yet!
Would this be a good experiment to set up for HS students as a part of the carbon cycle lesson or water cycle?
I’m assuming you’re talking about High School kids. This is research, not lesson plans. This project is not trivial. There is a lot going on. Postings are written a level most people can understand without losing too much of the meat of the subject. It’s meant to give us insight into how our ecosystem works. It’s not always oblivious.
On making lesson plans for HS kids, it maybe cost prohibitive because of the required instrumentation required to witness gas cycles. Over the years instrumentation costs and sizes have come down, but it still requires someone to put the electronics together where data is collected and presented. This can be done in a kit; however, there are a few ambitious science teachers putting small examples together.
Nitrogen cycle?
The nitrogen cycle is only one of many cycles going on in the tank. All of the cycles are being monitored and measured. Here is a list of only the gas cycles:
• CO2 to CH4 (redox – this is the whole spectra of ions from C -2 to C +4, some carbon cycles)
• NH4 to NO3 Nitrogen Cycle
• CH4 to O3 (V.O.C.s, methylation)
• Methane combined with CO2 and H2 to make CH4 and H2O.
• CO2 to O2 balance (part of a carbon cycle)
• Sulpher
How is this different from the biosphere in Arizona?
Putting aside all of the political squabbling Biosphere II cultivated, there are several reasons the Biosphere II in Arizona is very different than what I’m doing. BTY, Biosphere I is the Earth.
• Size – Biosphere II is over several acres of land holding several different ecosystems with very close Eco tones between them. The Eco tones tend to blend each ecosystem into one giant system. The system I’m building has no eco Tones, but only one ecosystem.
• Light/Heat – Biosphere II is located in the dessert where there is tons of light. A lot of effort is expensed to cool the whole system. The system I made is totally enclosed, keeping out light and heat. Light is produced with LEDs right for the plants inside the system, and a cooling system is used to chill the resulting heat from metabolic biological chemical changes.
• Water table – There is no permeable material for water to return to the water table. All of the rocks and structures are made by Disney Productions. The rocks and structures are made of some form of fiberglass and cement held up with rebar. Fresh water and Salt water are too close of proximity of each other without any interactions. CELSS uses only Fresh Water in this installation. The water table is constructed first, then a “water wick” is installed for delivering moisture to plant roots.
• Embracing anaerobic decomposition/construction – The assumption are only aerobic processes can make a sustainable system (Biosphere II). There is no decomposition via anaerobic processes which helps feed gas cycles like CH4 and CO2. CELSS uses anaerobic decomposition and construction to jumpstart the nitrogen cycle in water. (Dead rats work well). There is a balance/role for anaerobic and aerobic processes and electron exchanges between molecules. Electron exchange between atoms/organic molecules appears to be where life emanates.
The list continues……
Besides human social factor of one vs many which led to undoing!!
I’m not sure where you are going with this statement. Our Earth’s ecosystem is ever-changing. It will continue to change regardless what we do as a race. The Earth’s ecosystem is changing into some kind of balance on its own. That balance may or may not be conducive for human survival. If the Earth had a global conscience, I don’t think the human race is a concern. The gate keepers of life on Earth are not humans, animals, trees or plants. It’s bacteria. It’s the most abundant form of organic material on Earth. Without it, nothing else will exist.