2021-09-29

1

Water Resource Recovery:Future-Ready Wastewater Management in

the Circular Economy FrameworkJinkai Xue

Assistant ProfessorEnvironmental Systems Engineering

Faculty of Engineering & Applied ScienceUniversity of Regina

2021

Outline• Wastewater challenges in Canada• Future-ready wastewater management: Water resource recovery

(WRR)• Unit processes for WRR: examples• Integrated systems are needed• Our approaches• Selected previous and current projects

J. Xue 2

2021-09-29

2

J. Xue 3

Wastewater challenges in

Canadian cities

Large carbon footprint•Energy consumption•Greenhouse gas emission

Inefficiency and unknowns in removing emerging pollutants•Microplastics•Pharmaceuticals•Personal care products

Large volumes of sludge waste•Up to 50% of the total cost of wastewater management•Diverted pollution, e.g., to agriculture

Minimal to none resource recovery•Nutrients•Water resources•Energy

Not smart enough•Inadequate monitoring•Delayed response

(Images from internet)

How about the small/rural communities?

• ~20% Canadians rely on on-site wastewater treatment systems• Lack of maintenance/inadequately designed and constructed• Lack of adequate treatment• Nutrients• Organics• Micropollutants• Pathogens

• Significant risks to both surface and groundwater and public health

J. Xue 4

2021-09-29

3

Resources in municipal wastewater

• Organics: ~0.5 kg COD/m3, equivalent to ~7 – 8 MJ/m3

• ~5 times more embedded energy than needed for treatment

• Temperature: 10 – 20°C year-round in treatment facilities

• Nitrogen: ~30 g/m3

• Phosphorus: ~10 g/m3

J. Xue 5

Lin, et al. 2021

Wastewater is the new mine

J. Xue 6

Lin, et al. 2021

2021-09-29

4

Future-ready wastewater management:Water Resource Recovery Facilities (WRRFs)

• Reduced energy consumption or even energy positive• Resource recovery• Better removal of emerging pollutants• Reduced sludge production (e.g., down

to ~10%)• Resilience to future uncertainties, e.g.,

climate change context• AI-driven system control• Carbon neutrality

J. Xue 7

WRRFs

Carbon neutrality

Environ. & public health

Resource recovery

Smart

Unit processes for WRR

J. Xue 8

Physical

Membrane filtration

Media filtration

Adsorption

Evaporation

Chemical

Advanced oxidation

Coagulation/flocculation

Electrolysis

Precipitation

Biological

Suspended growth

Biofilms

Anaerobic digestion

2021-09-29

5

Integrated systems are needed• Multi-barrier based approaches: a combination of physical, chemical, and biological unit

processes• A variety of technologies can be organically integrated and optimized as per locally-specific needs

• Some considerations• Retrofit existing facilities, e.g., activated sludge• Stepwise upgrading• Enhance treatment capacity and performance• Resource-conscious• Energy efficient• Resilience

• Examples• Membrane bioreactors-ozonation• Membrane-aerated biofilm reactors• Granular sludge membrane bioreactors• Sedimentation-biofilter-ultrafiltration-UV

J. Xue 9

Case Study: Energy balance of a novel WRRF in 2020 in Europe

WWTP Energy Consumption (MWh)

WWTP energyconsumptionAd min bldg

Sewage Pumping

J. Xue 10

WWTP Energy Production (MWh)

Solar cell s

Heat recovery fro m ven tilation andheat pu mp sHeating energy

Coo ling energy

Biogas

0 50000 100000 150000 200000 250000

Consumption

Produ ction

Energy (MWh)

2021-09-29

6

WRR in municipalities: examples

J. Xue 11

AG-MBR

Influent

Sludge

Granular sludge

Permeate (Effluent)MABR

Clarifier

Influent Effluent

Sludge

Air

Biofilm on membrane surface

In addition• Struvite precipitation/fertigation for nutrient recovery• Anaerobic bioreactors for biogas production• Thermal heat recovery• Fertigation• Etc.

Enhanced treatment capacity and performanceBetter removal of emerging organic pollutantsReduced carbon footprintResilience under extreme climate conditions

WRR in small communities: an example

J. Xue 12

console.log(TMP, Q)

Adsorption

UF

Clean liquidFeed AI-Agent

Back

was

h

UV

• Clean water for reuse/discharge

• Spent adsorbent and composted solids for beneficial uses, e.g., soil amendment

• Smaller environmental footprint and carbon footprint

2021-09-29

7

There is no universally optimal solution

• Demographics• Culture• Environmental (climate) setting• Water resources• Wastewater quantity and characteristics• Regulations• Economics

• Locally optimized system designs and operating scheme

J. Xue 13

(Images from internet)

Our strategies and advantages

J. Xue 14

• Cold-Region Water Resource Recovery Laboratory (CRWRRL)• Novel system designs and operating schemes• Cutting-edge engineering approaches• Revolutionary water quality sensing technology

• State-of-the-art genomics tools• AI-driven wastewater management• Cost-effectively retrofit or upgrade the existing infrastructure

• Interdisciplinary collaboration• Engineering, Biology, Software, Economics

• Partnerships• University – Government – Industry - Communities

(Images from internet)

2021-09-29

8

Previous project #1: Treatment of oil sands tailing water (OSPW) using ozonation and membrane bioreactors (MBRs)

J. Xue 15

Raw OSPW

Ozonation

MBR

MBR

Permeate tank

Permeate tank

Raw OSPW MBR

Ozonated OSPW MBR

Previous project #1: Treatment of oil sands tailing water (OSPW) using ozonation and membrane bioreactors (MBRs)

J. Xue 16

Ceramic flat-sheet MF membrane:

Pore size 0.1 μm

~800 days of continuous

operation under various operating

conditions

Fresh or ozonated tailings water

NAs groups Removal rate (%)

Raw OSPW MBR Ozonated OSPW MBR Ozone + MBR Classical NAs 37.6 49.7 94.0

2021-09-29

9

Previous project #2: Novel Stainless-Steel-Based Conductive Membrane

J. Xue 17

polypyrrole (PPy)

• Good filtration performance• Better fouling control• Durable• Inexpensive

Previous project #2: Novel Stainless-Steel-Based Conductive Membrane

J. Xue 18

Sodium alginate (SA), Bovine serum albumin (BSA)Humic acid (HA), Secondary effluent (SE)

2021-09-29

10

Previous project #3: Are our water treatment facilities effective in removing microplastics?

J. Xue 19

0

20

40

60

80

100

120

0 10 20 30 40 50 60

Micr

opla

stic

rem

oval

(%)

Alum dose (mg/L)

3 µm6 µm25 µm45 µm90 µm

• Traditional treatment processes are effective in removing microplastics, e.g., > 80% of MPs 1 – 100 !m

• Optimal treatment conditions remain to be found for better microplastic removal• Multiple-barrier-based approaches are needed

Selected Ongoing Projects

• Novel wastewater treatment technology for emerging contaminants (NSERC Alliance;

with the City of Regina and others)

• Sustainable wastewater treatment and reuse in cold regions (NSERC Discovery Grant)

• SARS-CoV-2 Wastewater Surveillance (with colleagues in Science; the City of Regina, in-

kind contributor)

J. Xue 20

2021-09-29

11

References

• https://iwa-network.org/learn/circular-economy-tapping-the-power-of-wastewater/?ct=t%28EMAIL_IWA+Newsletter+Jan+2021_COPY_01%29

• https://cwn-rce.ca/project/assessment-and-management-of-environmental-risks-associated-with-decentralized-rural-wastewater-management-systems/

• Lin, S., Hatzell, M., Liu, R., Wells, G., & Xie, X. (2021). Mining resources from water. Resources, Conservation and Recycling, 175(August), 105853. https://doi.org/10.1016/j.resconrec.2021.105853

• Xue, J; Zhang, Y; Liu, Y; Gamal El-Din, M. (2016). Effects of ozone pretreatment and operating conditions on membrane fouling behaviors of an anoxic-aerobic membrane bioreactor for oil sands process-affected water (OSPW) treatment. Water Research. 105: 444-455.

• Xue, J; Zhang, Y; Liu, Y; Gamal El-Din, M. (2016). Treatment of oil sandsprocess-affected water (OSPW) using an anoxic-aerobic membrane bioreactor witha flat-sheet ceramic microfiltration membrane. Water Research. 88(1): 1-11.

• Zhang, Y; Wang, T; Meng, J; Lei, J; Zheng, X; Wang, Y; Zhang, J; Cao, X; Li, X; Qiu, X; Xue, J. (2020). A novel conductive composite membrane with polypyrrole (PPy) and stainless-steel mesh: Fabrication, performance, and anti-fouling mechanism. Journal of Membrane Science. 621: 118937.

• Xue, J; Peldszus, S; Van Dyke, M. I.; & Huck, P. (2021). Removal of Polystyrene Microplastic Spheres by Alum-Based Coagulation-Flocculation-Sedimentation (CFS) Treatment of Surface Waters. Chemical Engineering Journal, 130023. https://doi.org/10.1016/j.cej.2021.130023

• Xue, J; Samaei, S; Chen, J; Doucet, A; Ng, K. (2021). What have we known so far about microplastics in drinking water treatment? A timely review. Frontiers of Environmental Science & Engineering (in press).

J. Xue 21

Thank you.Jinkai Xuejinkai.xue@uregina.cahttp://uregina.ca/~jxv982/

J. Xue 22

Sponsors/Partners: