Real-Time Monitoring and Control of Urea Hydrolysis in Cyber-Enabled Nonwater Urinal System

Daniella Saetta, Arsh Padda, Xiushuang Li, Carlos Leyva, Pitu Mirchandani, Dragan Boscovic, Treavor Boyer

Research output: Contribution to journalArticle

Abstract

This research used a cyber-physical system (CPS) to monitor and control the extent of urea hydrolysis in nonwater urinals. Real-time pH and conductivity data were used to control urea hydrolysis inhibition under realistic restroom conditions with acetic acid addition. Variable urination frequencies and urination volumes were used to compare three conditions that affect the progression of urea hydrolysis. Mechanistic and conceptual models were created to evaluate the factors that influence the progression of urea hydrolysis in nonwater urinals. It was found that low urination volumes at low frequencies created ideal conditions for urea hydrolysis to progress. Alternatively, high urination volumes at high frequencies created pseudo-inhibitory conditions because it did not allow for sufficient reaction time or mixing with older urine in the urinal trap. The CPS was used to control urea hydrolysis inhibition by two logics: (1) reactively responding to a pH threshold and (2) predictively responding to past measurements using four lasso regression models. Results from the control logic experiments showed that acid was added once per hour under low use conditions and once in a 4 h experiment for high use conditions. The CPS allowed for full control of urine chemistry in the nonwater urinal, reducing the conditions (i.e., clogging and malodor) that have led to the removal of nonwater urinals in the United States.

Original languageEnglish (US)
Pages (from-to)3187-3197
Number of pages11
JournalEnvironmental Science and Technology
Volume53
Issue number6
DOIs
StatePublished - Mar 19 2019

Fingerprint

urea
Urea
hydrolysis
Hydrolysis
Monitoring
monitoring
urine
Acetic Acid
acetic acid
conductivity
experiment
Experiments
Acids
acid
Cyber Physical System

ASJC Scopus subject areas

  • Chemistry(all)
  • Environmental Chemistry

Cite this

Real-Time Monitoring and Control of Urea Hydrolysis in Cyber-Enabled Nonwater Urinal System. / Saetta, Daniella; Padda, Arsh; Li, Xiushuang; Leyva, Carlos; Mirchandani, Pitu; Boscovic, Dragan; Boyer, Treavor.

In: Environmental Science and Technology, Vol. 53, No. 6, 19.03.2019, p. 3187-3197.

Research output: Contribution to journalArticle

@article{a495c2eb8d894abf91996c6ad4c76115,
title = "Real-Time Monitoring and Control of Urea Hydrolysis in Cyber-Enabled Nonwater Urinal System",
abstract = "This research used a cyber-physical system (CPS) to monitor and control the extent of urea hydrolysis in nonwater urinals. Real-time pH and conductivity data were used to control urea hydrolysis inhibition under realistic restroom conditions with acetic acid addition. Variable urination frequencies and urination volumes were used to compare three conditions that affect the progression of urea hydrolysis. Mechanistic and conceptual models were created to evaluate the factors that influence the progression of urea hydrolysis in nonwater urinals. It was found that low urination volumes at low frequencies created ideal conditions for urea hydrolysis to progress. Alternatively, high urination volumes at high frequencies created pseudo-inhibitory conditions because it did not allow for sufficient reaction time or mixing with older urine in the urinal trap. The CPS was used to control urea hydrolysis inhibition by two logics: (1) reactively responding to a pH threshold and (2) predictively responding to past measurements using four lasso regression models. Results from the control logic experiments showed that acid was added once per hour under low use conditions and once in a 4 h experiment for high use conditions. The CPS allowed for full control of urine chemistry in the nonwater urinal, reducing the conditions (i.e., clogging and malodor) that have led to the removal of nonwater urinals in the United States.",
author = "Daniella Saetta and Arsh Padda and Xiushuang Li and Carlos Leyva and Pitu Mirchandani and Dragan Boscovic and Treavor Boyer",
year = "2019",
month = "3",
day = "19",
doi = "10.1021/acs.est.8b06126",
language = "English (US)",
volume = "53",
pages = "3187--3197",
journal = "Environmental Science & Technology",
issn = "0013-936X",
publisher = "American Chemical Society",
number = "6",

}

TY - JOUR

T1 - Real-Time Monitoring and Control of Urea Hydrolysis in Cyber-Enabled Nonwater Urinal System

AU - Saetta, Daniella

AU - Padda, Arsh

AU - Li, Xiushuang

AU - Leyva, Carlos

AU - Mirchandani, Pitu

AU - Boscovic, Dragan

AU - Boyer, Treavor

PY - 2019/3/19

Y1 - 2019/3/19

N2 - This research used a cyber-physical system (CPS) to monitor and control the extent of urea hydrolysis in nonwater urinals. Real-time pH and conductivity data were used to control urea hydrolysis inhibition under realistic restroom conditions with acetic acid addition. Variable urination frequencies and urination volumes were used to compare three conditions that affect the progression of urea hydrolysis. Mechanistic and conceptual models were created to evaluate the factors that influence the progression of urea hydrolysis in nonwater urinals. It was found that low urination volumes at low frequencies created ideal conditions for urea hydrolysis to progress. Alternatively, high urination volumes at high frequencies created pseudo-inhibitory conditions because it did not allow for sufficient reaction time or mixing with older urine in the urinal trap. The CPS was used to control urea hydrolysis inhibition by two logics: (1) reactively responding to a pH threshold and (2) predictively responding to past measurements using four lasso regression models. Results from the control logic experiments showed that acid was added once per hour under low use conditions and once in a 4 h experiment for high use conditions. The CPS allowed for full control of urine chemistry in the nonwater urinal, reducing the conditions (i.e., clogging and malodor) that have led to the removal of nonwater urinals in the United States.

AB - This research used a cyber-physical system (CPS) to monitor and control the extent of urea hydrolysis in nonwater urinals. Real-time pH and conductivity data were used to control urea hydrolysis inhibition under realistic restroom conditions with acetic acid addition. Variable urination frequencies and urination volumes were used to compare three conditions that affect the progression of urea hydrolysis. Mechanistic and conceptual models were created to evaluate the factors that influence the progression of urea hydrolysis in nonwater urinals. It was found that low urination volumes at low frequencies created ideal conditions for urea hydrolysis to progress. Alternatively, high urination volumes at high frequencies created pseudo-inhibitory conditions because it did not allow for sufficient reaction time or mixing with older urine in the urinal trap. The CPS was used to control urea hydrolysis inhibition by two logics: (1) reactively responding to a pH threshold and (2) predictively responding to past measurements using four lasso regression models. Results from the control logic experiments showed that acid was added once per hour under low use conditions and once in a 4 h experiment for high use conditions. The CPS allowed for full control of urine chemistry in the nonwater urinal, reducing the conditions (i.e., clogging and malodor) that have led to the removal of nonwater urinals in the United States.

UR - http://www.scopus.com/inward/record.url?scp=85062838466&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85062838466&partnerID=8YFLogxK

U2 - 10.1021/acs.est.8b06126

DO - 10.1021/acs.est.8b06126

M3 - Article

VL - 53

SP - 3187

EP - 3197

JO - Environmental Science & Technology

JF - Environmental Science & Technology

SN - 0013-936X

IS - 6

ER -