Study on Novel Bioreactors

Technology for Biodegradation of Oil

Sands Process-Affected Water

Lei Zhu

Supervisor: Dr. Tong Yu

2015-04-20

Department of Civil and Environmental Engineering

University of Alberta

Athabasca, Cold Lake and

Peace River, more than 75,000

square kilometres

Approximately 170.4 billion

barrels of recoverable bitumen

3rd largest proven oil reserves

Clark Hot Water Extraction

Background

http://en.wikipedia.org/wiki/Athabasca_oil_sands

1 billion m3 by 2025

¼ of Edmonton’s area

(176 Km2)

http://www.ibtimes.com/safety-measures-canadas-oil-sands-sector-are-increasing-

worker-protection-government-1359749

Biological Treatment

• Low capital and operating costs

• Oxidation of organic compounds

• Removal of inorganic compounds

• Nitrogen removal

• Operational flexibility

• Reduction of aquatic toxicity

• Microbial activities have been reported

in mature fine tailings (MFT)

• Commercial naphthenic acids was

degraded using indigenous microbes

from MFT

• Wastewater sludge from municipal

WTP could also be amended to MFT

for treatability test of OSPW

Advantages Feasibility

Long-term Goal:

To develop a feasible biological process train using

bioreactors for degradation of recalcitrant organic

compounds in OSPW

Research Objectives

Bioreactor Process Train

Biofilm Introduction

Biofilm is microbial growth on a surface or interface and consists of

microbial cells embedded in self-produced matrix of extracellular

polymeric substance (EPS).

http://aem.asm.org/content/72/3/2005/F1.expansion.html

1. Due to the biofilm diffusion limit, MBBR and MABR can

supply a good microenvironment for specialized microbes

to digest toxic organic compounds

2. Both of them exhibits greater resistance to the adverse

chemical conditions presented by industrial wastewater

than conventional biological treatment

3. Both of them have long sludge retention time, which will be

critical for specialized microorganisms to adapt the harsh

environment

4. Both of them can achieve aerobic and anaerobic conditions

inside the reactor

Bioreactor Selection

Bioreactor Design

Bioreactor Design

Water Characteristics

Item Description/Concentration (mg/L)

Colour Brown

Odour Hydrocarbon-like

COD 230

pH 7.5-8.8 (Test Value: 7.94)

Freezing Point 0℃

Alkalinity (mg/L CaCO3) 501.25

Cl- 627.33

SO42- 279.62

NO3- + NO2

- 2.41 (N mg/L)

NH4+ 1.95

NAs (FT-IR) 68.9

Water quality of OSPW from Suncor Energy Inc

Moving Bed Biofilm Reactor

Influent Port Sampling Port

Influent Pump

Effluent Port

Mechanical Mixer

Settling Flask

Influent Pump

Controller

Mechanical Mixer Controller

Effluent Storage Tank

Air Line

13Influent Port

Effluent Port

Internal Recycling Port

N2 Input

Compressed Air Input

Membrane Aerated Biofilm Reactor

Internal Recycling Port

Reactor COD Performance

MBBR

MABR

Stage 1 Stage 2 Stage 3

Stage 1 Stage 2

BOD Test Results

1. BOD in Raw OSPW, MBBR Effluent and MABR Effluent are very low, around 5 mg/L

2. The BOD/COD ratio in MBBR and MABR is larger than 0.3, which makes the environment

comfortable for bacteria inside reactors

3. Ozonation is useful for increasing the biodegradability of the effluent from MBBR

FTIR Test Results

DNA Sequencing Test Results

Statistics for 16S rRNA Gene Library

SampleOptimized Sequence

Number

OTU

Number

Coverage

(%)Chao Shannon

Raw OSPW (2013-04-

09) S10611352 7077 99.1 43532

(39819, 47665)4.30

MBBR Biofilm (2013-

05-01) S11777311 7637 99.3 33714

(31362, 36301)4.59

MBBR Suspended

Solid (2014-06-20) S1623440 5471 99.3 28986

(26347, 31960)4.12

MBBR Biofilm (2014-

06-20) S3813730 6185 99.4 30564

(27985, 33448)4.20

MABR Inoculum

Sludge (2014-02-20)

S12

849645 6427 99.5 33340(30448, 36582)

4.19

MABR Biofilm (2014-

06-20) S2544425 4372 99.4 17969

(16334, 19827)4.60

Miseq Illumina DNA Sequencing Test Results

• Proteobacteria was the

majority class and existed in all

six samples;

• α,β, γ-proteobacteria of all

reactor samples were lower

than that of Raw OSPW

• Flavobacteria: great

resistance under toxic and

alkaline environment

• Ignavibacteria found in MABR

Biofilm sample belongs to

Chlorobi phylum, which relates

to sulfur metabolism

• Nitrospira existed in biofilm

sample which is involved in

nitrification process

Top 10 microbial classified under Class Level

Heatmap for top 50 microbial classified under Genus Level

Miseq Illumina DNA Sequencing Test Results

• Nine Common genus for all 6 samples

• Pseudomonas: metabolic capability of

anteiso (β)-alkyl substituted aliphatic

carbon chain;

• Flavobacterium and Rhodobacter :

ternary substitution at positions other

than the β-position to the carboxylic

group of the main carbon chain.

• Steroidobacter: anaerobically on C-

18/19 as source of carbon with nitrate

as the electron acceptor.

• Methyloversatilis relate to heavy metal

and aromatic compounds resistant,

methylotrophic

• Bioaugmentation happened in MBBR

and MABR for All of the above three

microbial genus.

Conclusions

This process train with bioreactors was effective on enhancing

biodegradation of recalcitrant organic chemicals and reducing the

toxicity of OSPW.

Due to the nutrients condition, toxicity level and operation conditions,

the microbial community in raw OSPW was hugely different from that

inside bioreactors.

Bioreactors could select and enrich specific microorganisms which

showed great resistance to the harsh environment and the capability

of degrading carboxylic group of the main carbon chain.

Bioaugmentation happening inside MBBR and MABR made the

biodegradation of recalcitrant organic chemicals in OSPW faster and

the acceleration of end-pit lake reclamation promising.

Natural Sciences and Engineering Research

Council of Canada (NSERC)

Chinese Scholarship Council (CSC)

Suncor Energy Inc.

Acknowledgement

Thank you for

your attention.

Questions?