1. Urine Pretreatment for Wastewater Recovery
SEI
Engineers who solved Apollo 13’s problems
Blesson

2. Overview Background Objectives Laboratory Tests
Distillation Simulation
Results Summary
Team Accomplishments
Future Tasks
Acknowledgements
Blesson

3. Team Structure Name Major Year Position Moriah Thompson
Biomedical Eng. 4
Project Lead
Sara Guest
Chemical Eng.
Data and Simulation Lead
Elizabeth Joachim 3
Lab Lead
David Moore
Civil Eng. 1
Assistant Lab Lead
Sandhya Ramesh
Logistics Lead and lab work
Marco Cienega
Mechanical Eng.
Assistant Logistics Lead
Blesson John
Webmaster
Blesson 3

4. Water Use and Recovery Water currently resupplied via shuttle
Not economical or practical to re-supply water for long term missions
Blesson

5. ISS wastewater sources
Distribution
Consumption
Hygiene
Exhalation
Perspiration
Humidity
Condensate
Urination
Hygiene Waste
Moriah
Urine pretreatment protects hardware and plumbing system form clogging
Solids precipitation
Biofilm formation

6. Current Urine Pretreatment
“String of Pearls”
Not compatible with reclamation system
Moriah
Urine and Fecal collection Unit 6

7. Problem Statement
The current pretreatment method utilizes a toxic chemical with little known toxicological information that may be detrimental to astronaut health over time.
Moriah 7

8. Previous work
Supernatant Characterization from urine MAP precipitation:
Chemical urine pretreatment:
TOC > EPA drinking water limit
Organics and Inorganics removal is needed
High pH buffer
Need to optimize precipitation reaction
Sulfuric Acid
Sodium Benzoate
Acetic Acid
Glycolic Acid
Sodium Permangante
Phosphoric Acid
So far we have worked on this problem and this is what we have done so far. Explain the objective for each of the previous work and say it was presented in E&S.
Work presented in the 11th International Conference on Engineering, Science, Construction, and Operations in Challenging Environments (Earth & Space Conference) 8

9. Cascade Distillation Subsystem currently used for water reclamation
Marco
Centrifugal vacuum distillation

10. Project Objective
Identify a non-toxic pretreatment alternative that is compatible with a distillation based water reclamation system.
marco 10

11. Project Tasks Task 1- Laboratory tests Select pretreatment chemicals
Toxicity data, HMIS, pKa, Volatility
Test chemicals’ pretreatment ability
Task 2- Distillation simulation (Aspen)
Research Cascade Distillation Subsystem
Determine simulation operation conditions
Simulate chemicals tested in Task 1
Marco 11

12. Task 1-Laboratory Test
Objective: Compare pretreatment chemicals to sulfuric acid in stored urine (1g/L)
Chemical: pH
Physical: TSS, Turbidity
Biological: Protein, Ammonia, DO
Sandhya
Monitor the biological, chemical, and physical changes occurring in the stored urine following the addition of pre-treatment agent. Metrics of success: Chemical- constant pH, Physical- constant TSS, Biological- constant protein, ammonia and DO

13. Chemicals Selected 1 g/L as active ingredient
Chosen based on solubilty, pKa, and toxicity
Delivery system for solid chemicals depends on solubility
Sulfuric Acid
Fumaric Acid
Sorbic Acid
Boric Acid
Lactic Acid
Phthalic Acid
Sandhya

14. Experimental Methods Urine collected Urine collection carboy
Sandhya
This is how we started the experiments. Urine was collected no earlier that 4hr before according to…then explain the flowchart including Urine is equally distributed in the reactors and pretreatment chemical is added
Samples are taken at predetermined times 14

15. Analytical Methods pH TSS Dissolved Oxygen Turbidity Ammonia
Sandhya
The pH, or acidity, of each sample should fall within a certain range to keep solids from precipitating and bacteria from forming.
Dissolved Oxygen (DO), a measure of the amount of oxygen dissolved in the solution, indicates the amount of bacteria activity in the sample.
The Phenate Method measures the amount of ammonia in a solution, indicating the activity of bacteria in the sample.
Total Suspended Solids (TSS), a measurement of the amount of solid particles suspended in a liquid, is used to measure the amount of precipitation that occurs in the urine sample over time.
Turbidity, a measure of the cloudiness of a fluid, also indicates the amount of particles suspended in the solution.
Protein Assay measures the amount of protein in a solution, indicating the presence of the enzymes bacteria use.
Ammonia
Phenate Method
Protein Assay

16. Chemical Test Results
Libby

17. Physical Tests Results
Libby

18. Biological Tests Results
Libby

19. Biological Tests Results
Libby

20. Task 2- Simulation Objectives:
Determine % water recovery at proposed operating conditions
Determine % acid recovery at proposed operating conditions
Sara
Monitor the biological, chemical, and physical changes occurring in the stored urine following the addition of pre-treatment agent. Metrics of success: Chemical- constant pH, Physical- constant TSS, Biological- constant protein, ammonia and DO

21. Flash Operating Conditions
Simulation Conditions
One stage flash (worst case scenario)
Feed Conditions
Temperature °C 40
Pressure psi
14.69
Volume Fraction
Chemical
0.04
Water
0.96
Flash Operating Conditions
Temperature °C
25-50
Pressure psi
Sara
The simulation operating conditions are based off information from NASA papers. There was not an exact feed description in terms of flowrates to the CD system. There is a description of the urine pretreatment chemical volume and the urine volume. We can only model an acid, water separation in Aspen. So, I treated the urine as if it were all water. The numbers from the paper are 1000ml urine and 40 ml of pretreatment chemical. From that I decided the feed would be 960 ml of water and 40 ml acid. There was no feed pressure, so I assumed 1 atm or psi. The important pressure is the flash pressure which is zero. Our goal is to show the effect of the acid on the recovery of water. Are we able to recover the water in the operating range of the CD system (max 50°C). Also, is there one acid that is easier to separate than the others and how do the acids compare with the effect sulfuric acid would have on the separation. The system was modeled as a one stage flash even though there are possibly 5 cascades. One flash assumes worst case scenario. So far, sulfuric, fumaric, and boric are separable from water in the flash operating range of 25-50°C. The lower the flash temperature the less acid is recovered with the water and more water is lost with the acid/waste/liquid stream. However, the differences are very small 5E-5 to 5E-4 mass fraction of sulfuric acid in water. Results so far indicate that the acid should not negatively effect water recovery. It would be nice to have a specification for the maximum acid content in the recovered water. 21

22. Simulation results
Sulfuric, fumaric, and boric are separable from water in the flash operating range of 25-50°C
Currently unable to simulate sorbic acid
Separation Efficiency:
Sara 22

23. Results Summary Laboratory tests results:
Chemicals tested do meet pretreatment requirements for short term storage
Chemicals tested do not meet pretreatment requirements for long term storage
Distillation results:
Chemicals are separable from water in the flash operating range of 25-50°C.
Preliminary simulations indicate that high % chemical removal is possible
David

24. Future Tasks Laboratory tests Simulation Lactic acid Phthalic acids
Separation efficiencies
David

25. Acknowledgements
Julianna Camacho Dr. Autenreith Dr. Pickering Magda Lagoudas Urine Video
David