Urine Pretreatmentfor Wastewater Recovery

Space Engineering Institute

Final Presentation

2008-2009

Overview– Background– Previous Work– Objectives – Task 1: Laboratory Tests– Task 2: Distillation Simulation– Future Tasks: UV Urine Pretreatment

Team Structure

Name Major Year Position

Moriah Thompson Biomedical Eng. 4 Transitional Team Lead

Julianne Larson Aerospace Eng. 4 Project Lead

Elizabeth Joachim Biomedical Eng. 3 Lab Lead

Marco Cienega Mechanical Eng. 3 UV Lead

David Moore Civil Eng. 1 Assistant Lab Lead

Sandhya Ramesh Biomedical Eng. 1 Logistics Lead

Blesson John Biomedical Eng. 1 Webmaster

• Retire shuttle

• Explore the Moon

• Build lunar habitat

• Explore Mars

• Build Martian habitat

• Explore other destinations

Vision for Space Exploration

Human Habitation Challenges

Not economical or practical to re-supply

basic life support elements from Earth

Source: NASA

What Part Do We Focus On?

Specifically urine pretreatment

Why Urine Pretreatment?

• Protect hardware and plumbing system form clogging

– Solids precipitation

– Biofilm formation

Current Urine Pretreatment

“String of Pearls”

Urine and fecal collection unit

Oxone is toxic!!Not good for

astronauts or water reclamation system

Problem Statement

The current pretreatment method utilizes a toxic chemical that may be detrimental

to astronaut and system health.

Previous Work

• Urine Pretreatment for Biological Reclamation

• Supernatant Characterization from urine MAP precipitation

Work presented in the 11th International Conference on Engineering, Science, Construction, and Operations in Challenging Environments

(2008 Earth & Space Conference)

Urine Pretreatment for Biological Water Recovery

Objective:Identify a non-toxic pretreatment alternative that is compatible with

a biological water reclamation system.

Test stand for biological water recovery (JSC)

pH Results Ammonia Results

Glycolic Acetic Sulfuric

Urine Pretreatment for Biological Water Recovery

Urine Pretreatment for Biological Water Recovery

Chemicals Tested:•Sulfuric Acid•Sodium Benzoate•Acetic Acid•Glycolic Acid •Sodium Permanganate•Phosphoric Acid

Test stand for biological water recovery (JSC)

Supernatant Characterization from Urine MAP Precipitation

Objectives:•Determine the composition and buffer capacity of supernatant

•Identify uses of supernatant

•Determine treatment process necessary for water recovery

SEM micrograph of MAP precipitates produced by Zhao

TOC Results Buffer Capacity

Supernatant Characterization from Urine MAP Precipitation

Conclusions:•TOC > EPA drinking water limit

•Removal of inorganics is needed

•Buffer at high pH values

•Optimization of precipitation process is needed

Supernatant Characterization from Urine MAP Precipitation

SEM micrograph of MAP precipitates produced by Zhao

Current Project Objective

Identify a non-toxic pretreatment alternative that is compatible with a distillation based

water reclamation system.

Proposed Water Reclamation System

Cascade Distillation Subsystem Orion Crew Module

Project Tasks• Task 1- Laboratory tests

– Select pretreatment chemicals

• Toxicity data, HMIS, pKa, Volatility

– Test chemicals’ pretreatment ability

• Task 2- Distillation simulation (Aspen)– Determine simulation operation conditions– Simulate chemicals tested in Task 1

Task 1-Laboratory Tests

– Chemical: pH– Physical: TSS, Turbidity– Biological: Protein, Ammonia, DO

Objective: Compare pretreatment chemicals to sulfuric acid in stored urine (1g/L)

Chemicals Selected

• Chosen based on– Solubility

– pKa

– Toxicity– HMIS

• Considerations– Delivery system– Astronaut health– System health

Sulfuric Acid

Fumaric Acid

Sorbic Acid

Boric Acid

Lactic Acid

Phthalic Acid

Experimental Methods

Urine collected

Samples are taken at predetermined times

Analytical Lab Methods

Total Suspended Solids

Turbidity

pH

Protein Assay

Dissolved Oxygen

PhenateMethod (Ammonia)

Chemical Tests

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Task 2- Simulation

Objective: Determine % water recovery at proposed operating conditions

FEED

VAPOR

LIQUID

FLASH

Feed ConditionsTemperature (°C) 40

Pressure (psi) 14.69Vapor Fraction 0

Volume Fraction  Chemical 0.04

Water 0.96

Flash Operating Conditions

Temperature (°C) 25-50Pressure (psi) 0

One stage flash (worst case scenario)

Simulation Conditions

Simulation Results

% Water Recovery % Chemical RecoveryFumaric Acid 98.49 99.59Sulfuric Acid 96.94 99.98Boric Acid 99.97 81.97

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.– Determine operating conditions to achieve >99% pretreatment

agent removal by volume– Add ionic strengths to mimic influent urine stream

Future Tasks: UV Urine Pretreatment

Characteristics of UV Disinfection• Germicidal or UV-C range: 200 – 280nm• UV light rearranges DNA

• Thymine dimers formation• Replication is prevented

Accomplished Tasks• Developed work plan• Determined absorbance of untreated urine

Urine

Water

Germicidal range

1.E+00

1.E+01

1.E+02

1.E+03

1.E+04

1.E+05

1.E+06

1.E+07

1 10 100 1000 10000

Day 0

Day 1

Day 6

Future Tasks • Task 1- Determine preliminary apparatus design

– Housing unit design– Light intensity– Distance – Exposure time– Others

• Task 2- Analyze performance of preliminary design

– Determine changes needed for next design

secsec

22Time

cm

WIntensity

cm

WDose

2008-09 Team Accomplishments• Publications

– AIAA Regional Conference proceedings– 2nd Civil Engineering Student Research Symposium proceedings– TAMU Undergraduate Journal

• Presentations– AIAA Regional Conference, San Antonio, TX– 2nd Civil Engineering Student Research Symposium, TAMU – Student Research Week, TAMU – SEDS Space Vision Conference, TAMU

• Awards– 2nd place: TAMU Student Research Week– Only undergraduate presentation at the 2nd CESRS, AceDocs

Past Team Accomplishments2007-2008Publications• AIAA Regional Conference proceedings• ASCE Earth and Space proceedings (1) • ASCE Earth and Space proceedings (2)

Presentations• AIAA Regional Conference, Houston, TX• 2008 ASCE Earth and Space Conference,

Long Beach, CA (1)• 2008 ASCE Earth and Space Conference,

Long Beach, CA (2)• TAMU Student Research Week

Awards• 2nd Place: Weirdest Job on Campus

2006-2007Presentations• TAMU Student Research Week• Prairie View A&M Undergraduate

Research

Awards• 2nd Place: TAMU Student Research Week• 3rd Place: TAMU Student Research Week

2005-2006Presentations• TAMU Student Research Week

Awards• 2nd Place: Weirdest Job on Campus

Acknowledgements

– Dr. Pickering (JSC) – Dr. Muirhead (JSC) – Dr. Boulanger (TAMU)– Dr. Autenreith (TAMU)– Dr. Miskevich (TAMU-Commerce)– Ms. Lagoudas (TAMU-SEI)

Questions?