Discipline: Technology and Engineering
Subcategory: Environmental Engineering
Lucien Gassie - University of Miami
Co-Author(s): James Englehardt, Jian Wang, Nichole Brinkman, Jay Garland, Tingting Wu, Piero Gardinali, and Tianjiao Guo
Net-zero water (NZW) systems, or water management systems achieving high recycling rates and low residuals generation so as to avoid water import and export, can also conserve energy used to heat and convey water, while economically protecting local eco-hydrology. However, design and operating experience are extremely limited. The hypothesis is that a mineralizing, urban NZW system can meet water reuse requirements recommended by the WateReuse Research Foundation at a cost competitive with existing wastewater and water treatment technology, including 12 log virus inactivation, federal and state drinking water standards, and destruction of organic compounds below 0.7 mg/L chemical oxygen demand. The objective of this research is to present the results of the second phase of operation of an advanced oxidation-based NZW pilot system designed, constructed, and operated for a period of two years, serving an occupied four-person apartment. System water was monitored, either continuously or thrice daily, for routine water quality parameters, minerals, and MicroTox® in-vitro toxicity, and intermittently for somatic and male-specific coliphage, adenovirus, Cryptosporidium, Giardia, emerging organic constituents (non-quantitative), and the Florida drinking water standards. All 115 drinking water standards with the exception of bromate were met in this phase. Neither virus nor protozoa were detected in the treated water, with the exception of measurement of adenovirus genome copies attributed to accumulation of inactive genetic material in hydraulic dead zones. All but six of 1006 emerging organic constituents analyzed were either undetected or removed >90% in treatment. Total dissolved solids were maintained at ~500 mg/L at steady state, partially through aerated aluminum electrocoagulation. Bromate was measure above the 10 g/L drinking water standard in this phase. However, accumulation is projected to be controlled in the future by aluminum electrocoagulation with separate disposal of backwash water. Additional study on requirements for long-term microbiological control is suggested. Finally, while in phase II a UV/H2O2 process was examined for the advanced oxidation process (AOP), the peroxone-based system studied in phase I of the project is projected to save more energy than is consumed in treatment due to retention of wastewater thermal energy, making the system energy positive when peroxone is used as the AOP. More in-depth analysis of system energy and emissions are proposed. Further development of such systems and their automated/remote process control systems is recommended.
Funder Acknowledgement(s): US National Science Foundation (EFRI-SEED Award 1038257), US Environmental Protection Agency, University of Miami, Engineered Control Systems, Inc., BioMicrobics, Inc., Wastewater Technologies, Inc., Florida International University, Hazen and Sawyer, BK Precision Corp., RTI Supply, Spartan Environmental Technologies
Faculty Advisor: James Englehardt, firstname.lastname@example.org
Role: Management of the undergraduate research team to direct sample analysis, operation of the system for experiments, and collaboration with US EPA and Florida International University to complete specific experiments to close the project. Also completed data analysis and preparation of the manuscript submitted to Water Research.