Discipline: Biological Sciences
Subcategory: Environmental Engineering
Jasmine Walker - Central State University
Co-Author(s): Peter Ling, The Ohio State University, OH
A compost system was designed and created to test sustainable food production for National Aeronautics and Space Administration’s usage in deep space exploration. This experiment aims to take agriculture in space to new limits by utilizing a new method to make substrate renewable for generations of crops through composting without continuously inputting harmful chemicals to achieve healthy soil conditions. Using recycled substrate would benefit a new world of agriculture by providing a cheaper economic alternative while producing the same results. NASA’s current substrate source used for harvesting food is costly, hard to maneuver in a limited environment, and finally takes up valuable storage on the space craft. In order to assess this idea, a tabletop bioreactor was established in a closed, insulated environment to help monitor the decomposition rate. The resulting products yielded from the bioreactor will be used to cultivate crops for future consumption in hopes of reaching sustainability. Tomato leaves, straw, and food scraps were gathered and compacted into the bioreactor once prepared. The selected items were based on a variety of circumstances including moisture content and carbon to nitrogen ratios the item obtains in this experiment. A minimum temperature of 60 degrees Celsius is the standard measurement in order to start the thermophilic progression. As this condition begins, human and plant pathogens which are the primary causes for diseases in composting, are destroyed in this process. During an eighteen day time span data was collected in regards to temperature fluctuation through three sensors inserted through the insulated bioreactor’s openings. After a thorough analysis of the results gathered, the temperature recordings indicated that the tabletop bioreactor did not reach the anticipated 60 degrees Celsius point and the early stages of thermophilic decomposition could not be met. Instead, a low temperature of 29 degrees Celsius was the constant temperature of the system that indicated the compost material remained in the mesophilic stage of decomposition. After a careful analysis was completed of the materials were completed, indication of decomposition was apparent; yet, this project is not ready to be used for NASA’S purposes. The next steps are to understand the bioreactor to produce sustainable results by using equipment such as an OxyTemp probe to calculate temperature at different sectors in the compost and oxygen levels simultaneously. As a result, aeration of the system will be conducted to shorter time periods from every five hours to every nine hours for the possibility of reaching the thermophilic decomposition stage.NSF Abstract.pdf
Funder Acknowledgement(s): NASA X-Hab Academic Innovation Challenge Program The Ohio State University SROP Program
Faculty Advisor: Augustus Morris, firstname.lastname@example.org
Role: During the experimentation process, I gathered the materials needed to be tested in the bioreactor chamber which would include the tomato leaves, straw, and food scraps. I was also able to set a timeline for when the information and tasks should be completed in order to reach deadlines regarding the project. Once the material was inserted into the bioreactor, I was able to monitor a software system to control the air circulation the compost obtained in increments of two to five hours. Finally, I designed a power point presentation, as well as, a poster presentation that presented the findings gathered.