Great Opportunities for

Anaerobic Digestion

Juan M. Lema

Department of Chemical Engineering

University of Santiago de Compostela, Spain

Castelló, 7 de julio de 2016

Enhancing biodegradability

and production of VFA

Very high polluted

Wastewaters

Waste water

Organic suspended solids

+

Wastewaters with toxic compounds

Effluent

ANAEROBIC TREATMENT

Biotransformed effluent

A

B

C

E

Hydrolysis Acidification

Hydrolysis or Acidification or

(Methanogenesis)

Hydrolysis Acidification

(Methanogenesis)

Hydrolysis Acidification

Methanogenesis

N- containing

wastewaters

Wastewaters with organics, sulphate and heavy metals

Effluent

Effluent

D Metal sulphide removal

Denitrification Nitrification

Acidification Sulphate reduction

Methanogenesis

-The core of integrated processes (2001)

(Lema & Omil, Water Sci.Technol 2001)

-Papers on Anaerobic Digestion (Scopus)

0

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1981-85 1986-90 1991-95 1996-2000 2001-05 2006-10 2011-15

-Papers on Anaerobic Digestion (Scopus)

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1981-85 1986-90 1991-95 1996-2000 2001-05 2006-10 2011-15

Bior.T

WST

WR

WER

WM

-Source

Sewage Treatment Plant

COD, N, P

CO2

Energy

Treated water

Solids Sludge

-Conventional STP

Sewage Treatment Plant

COD, N, P, Solids

Micropollutants

CO2 VOCs GHG

Energy

Reuse water

Biosolids

Recovery products

-A more advanced concept: Eco-Innovation

8

-“3 R” Objectives in WW Treatment

Reduce

Water and sludge of sufficient quality

Energy, Metals Chemicals, Nutrients , Bioplastics, Electricity, Cellulose...

Energy, Sludge, Space, Emissions, CAPEX, OPEX

Re-use

Recover

-“3 R” Innovation in WW Treatment

Retrofit

Re-Think New flowsheets

New conceptions

Include new units

Re-imagine

-New opportunities for AD

Sewage treatment (Retrofit) (Re-think)

Sewage treatment (Re-think)

BioMethane Biorefinery (Re-imagine)

Recover

Reduce

Reuse

Sewage Anaerobic Treatment

Reduce

Primary settler

Influent Effluent

Thickening tank Primary sludge

Sludge digester

Biogas

Thickening tank Secondary sludge

Anoxic Aerobic Activated sludge reactor

Dehydration system

Dehydrated sludge

Secondary settler

Water line Sludge line

Aeration

-Retrofit

13

-Anammox

Partial nitrification

Anammox Two steps

-Nitrogen removal by Anammox

One step.

O2

NH4+

NO2-

Anoxic

Anammox

N2 + NO3

-

Aerobic

Decantación

Primaria

Entrada

Efluente

Espesadores

Fango Primario

Digestor

Anaerobio

Biogás

Tambores Espesado

Fango Secundario

Anóxico Aerobio

Sistema de lodos activos

Centrífugas de

Deshidratación

Lodo

Deshidratado

Decantación

Secundaria

Línea de agua

Línea de lodos

Pozo

Gruesos Bombeo

Pozo de

Fangos mixtos

Arena

Desarenador

Desengrasador Desbaste

Finos

Depósito de

Fangos Secundarios

Finos Gruesos

ELAN®

Cristalizador

NH4MgPO4

- STP Guillarei- Tui

-ELAN®. Guillarei-TUI (Spain)

Curitiba – Brazil

UASB reactors + DAF

• Design population: 600,000 inhabitants

• Flowrate: 1,100 L/s

-Anaerobic treatment of Sewage

-Anaerobic treatment of Sewage at moderate T

Biogas

• Nutrients •CH4 emissions

•Energy savings •Low biomass production

Anaerobic

UASB

Primary treated Urban wastewater

20 – 30 ºC

-Pilot Plant in Rotterdam (main stream)

-Anammox on main stream at low T

Direct growth on wastewater possible until 10 C No direct negative influence of BOD

Lotti et al. ES&T 2014

Temp. RateTot-N RateTot-Nmax qmax

°C g-N L-1 d-1 g-N L-1 d-1 g-N2 g-VSS-1 d-1

20 1.85 2.38 0.60

15 1.19 1.58 0.30

13 0.51 0.69 0.12

10 0.34 0.34 0.06

Primary settler

Influent Effluent

Thickening tank Primary sludge

Sludge digester

Biogas

Thickening tank Secondary sludge

Anoxic Aerobic Activated sludge reactor

Dehydration system

Dehydrated sludge

Secondary settler

Water line Sludge line

Aeration

-Rethinking STPs

22

Primary settler Influent Effluent

Thickening tank

Primary sludge

Sludge digester

Biogas

Thickening tank

Secondary sludge

Aerobic

SRT: 2 d

Dehydration

system

Dehydrated

sludge

Secondary

settler

Water line

Sludge line

ADN

ADN

Increase sludge production Decrease aeration requirements Low extent nitrification

NH4+ removal (suboptimal T)

T- P

Low temperature Anammox system

NH4 + removal (optimal T)

-High Rate (Low SRT) reactor + Anammox

Anammox

Thermal Hydrolysis

Enhanced precipitation (80% TSS removal)

-Enhanced precipitation (EP)

-EP. Plant Wide Modeling Simulation *

Variable Increase/Decrease

Oxygen - 22%

Electricity production +33,6 %

Biogas Production + 35 %

Sludge production - 8%

-60%

-40%

-20%

0%

20%

40%

60%

O2 Sludge Energy BGAS Electr

TPT + ANMX TPT +ENH.PREC.+ANMX TPT + HIGH RATE + ANMX

*

Thanks to Tamara Fernandez-Arévalo

Reduce

-Plant Wide Modeling Simulation

Primary settler

Influent Effluent

Thickening tank Primary sludge

Sludge digester

Biogas

Thickening tank Secondary sludge

Anoxic Aerobic Activated sludge reactor

Dehydration system

Dehydrated sludge

Secondary settler

Water line Sludge line

Aeration

-Re imagining

27

-ALL GAS Project

Influent Preliminary Treatment

Primary Sedimentation

Tank

Effluent Activated Sludge

Sludge Disposal

Dewatering

Thickener

Digester

Biogas

Anaerobic Process

Biogas

Algae Pond

Dewatering

Fertiliser

Waste biomass

Disintegration of solids

-Raceway

-Extension to 4 Ha. 2500 m3/d = 25 % of STP flow

- Granular anaerobic MBR and nutrient absorbers.

Screen Primary

Sedimentation

Raw wastewater

anMBR

1 ry / 2 ry

sludge Thickener

Sludge supernatant ( Return liquor )

Stabilised sludge to land

Anaerobic digester

Sludge recirculation loop to heat exchanger

Gas engine

Imported grid electricity

Digested sludge pump

Primary sludge pump

Thickened Primary sludge pump

Disposal of gross solids

Produced biogas

Treated effluent

Nutrient rich eluent

N - C

o n

t a c

t o r

P - C

o n

t a c

t o r

Sewage Anaerobic Treatment

Reuse

-Anaerobic + Aerobic MBR (for water reuse)

•Low-strength •Ambient temperature

UASB

•Energy savings •Low biomass production

MBR

Air

High quality effluent (COD, SS, microbiology)

Permeate

CH4 emissions

25-50% CH4

(dissolved)

Biogas

Primary treated Urban wastewater

10 – 20 ºC

Anaerobic

50-75% CH4

(biogas)

25-50% CH4

(dissolved)

Anoxic Aerobic

pe

rme

ate

NO3-

NH4+

NH4+

O2

CH4 + NO3

N2

wa

ste

wate

r

CH4 (GHG)

Aerobic

CH4 global warming potential of 25

-SIAM ® Concept

Denitrification coupled to methane oxidation

Aerobic pathway Anaerobic pathway

35

With 25 mg CH4·L-1

NC10

ANME-2 + Anammox

Methanotrophs + denitrifiers

35 mgTN·L-1 removed

58 mgTN·L-1 removed NO2

NO3

118 mgTN·L-1 removed NO3

-Background: CH4 & N removal

17 mgTN·L-1 removed

-Pilot plant (SIAM)

1

3 2

1 UASB reactor (141 L) 2 Anoxic Chamber (42 L) 3 Aerobic Membrane Chamber (22 L)

Supplier Zenon

Type Hollow fiber

Matherial PVDF

Pore size 0.04 µm

Area 0.9 m2

Support

-CH4 released

0

10

20

30

40

50

60

0 50 100 150 200 250 300

CH

4 (

mg·

L-1

)

Time (d)

CH4 influent CH4 Permeate

VIII I II III IV VI VII

-SIAM- MBR Comparison

AnMBR MBR SIAM

Flux (L/m2·h) 5-10 16-24 12-17

Energy (kWh/m3) -0.5/-0.7 0.2/0.4 -0.5/-0.7

Energy membrane 0.8/ 1.2 0.4/0.6 0.5/ 0.7

Total Energy 0.3/ 0.5 0.6/1.0 -0.2/ 0.2

CH4 emissions Yes Yes No

Denitrification No Yes Yes

Sludge surplus (kg SST/m3)

0.08/0.16 0.2/0.3 0.08/0.16

J. Garrido et al, 2015)

-Pilot plant (SIAM)

(STP Cartagena, Murcia, Spain)

1.- Biomethane

Recover

Biogas

production in

Europe (2014)

Anaerobic (co) Digestion

Quality? Maximum production?

Proportions? Loading rate?

-Co-substrates blending... Let’s try!

-A more rational approach

DIAGNOSIS CONTROLLER

FILTER BLENDER

Indicator C

Mo

dif

ica

tio

n o

f o

pe

rati

on

al

rest

rict

ion

s

fCH4

fRatio

Alkalinity Ratio

Flow CH4

Linear Programming Optimisation method

xi (% vol.)

HRT

Linear restriction LOW HIGH

OLR (g COD/L·d) 0 5

N-TKN (g N/L) 0.2 4

Moisture (kg H2O/kg) 0.85 1.0

Lipids (g/L) 0 10

Alkalinity (g CaCO3/L) 2 8

Na+ (g/L) 0 3

Biogas quality (ppm H2S) 0 10,000

Digestate quality (g COD/L) 0 6

dt

dttRatioRatio

)(

dt

dttQQ

CH

CH

)(4

4

Ratio* QCH4* Control cycle = ¼ HRT

Ratio

QCH4

(Set Points)

0

0· 4

RatioRatio

RatioCHRatio

fiff

fifffCIndicator

LOWHIGHCURRENT LimitLimitCLimit ·Limit NEW

Apply to most active restriction

-Closed-loop control strategy

ANAEROBIC DIGESTER

(García-Gen et al , Water Research, 2015)

-Operational strategy: Industrial pilot plant

(EDAR de BENS. A Coruña, Spain

-Change of substrates fraction and OLR optimization

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1

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4

5

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20

30

40

50

60

70

80

90

100

0 129 139 150 160 170 180 190 200 213 221 230 238 247

OL

R (

g D

QO

/L·d

)

% S

us

tra

te

(%C

OD

)

(days)

(García-Gen et al, 2015)

-OLR perturbations

0

1

2

3

4

5

6

7

8

0,0

1,5

3,0

4,5

6,0

7,5

9,0

10,5

12,0

100 120 140 160 180 200 220 240

Ace

tic

and

pro

pio

nic

co

nce

ntr

atio

n (

g L-1

)

O

LR (

g C

OD

L-1

d-1

); B

ioga

s (L

L-1

d-1

)

Time (d)

(Regueiro et al. XXXXXXX 2015) Regueiro et al. Biores.Technol. (2015)

-Microbiome as an “early indicator”?

0

0,1

0,2

0,3

0,4

0,5

0,6

0,7

0,8

0,9

1D

ay1

50

Day

16

8

Day

17

2

Day

17

4

Day

17

9

Day

18

1

Day

18

9

Day

20

0

Day

21

0

Day

21

7

Cu

mu

lati

ve p

rop

ort

ion

at

fam

ily le

vel

f_[Cloacamonaceae]

f_Pseudomonadaceae

f_Actinomycetaceae

f_Dethiosulfovibrionaceae

f_Anaerobaculaceae

f_Bacteroidaceae

o__Bacteroidales

f_Porphyromonadaceae

o_Clostridiales

o_MBA08

f_Peptococcaceae

f_Acholeplasmataceae

f_Lachnospiraceae

f_Caldicoprobacteraceae

o_Clostridiales

f_Peptostreptococcaceae

f_Ruminococcaceae

f_Erysipelotrichaceae

f_Syntrophomonadaceae

f_Carnobacteriaceae

f_Clostridiaceae

f_[Tissierellaceae]

OLR

5

OLR

2

OLR

2

OLR

5

OLR

10

(Regueiro et al. Biores.Technol. 2015)

(Carballa et al. Current Opinion Biotechnol. 2015)

-Biogas upgrading to Biomethane

-Biomethane plant

-Biogas upgrading plants (2012)

http://www.iea-biogas.net/files/daten-redaktion/download/Technical%20Brochures/biomethane-status-2014.pdf

277 plants

-Commercial Technologies

- Scrubbing (Water or Organic solvents)

(Yang, Ge et al. 2014)

-Pressure Swing Adsorption

Biogas upgrading plant Mühlacker, GE (1000m³/h)

-Membrane separation

-CAPEX

Sun Li et al Renewable and Sustainable Energy Reviews, 2015

4 H2 + CO2 CH4 + 2 H2O

PATENT

PA: 61/563,247

Feed and produced CH4 are sparged through the membrane module to

create fine bubbles

-Lab-Scale Biological Upgrading

Díaz, I et al . Biores.Technol.. (2015)

T

P

BIOMETHANE

LIQUID EFFLUENT

GAS FLOWMETER

SAMPLING

POINT

GAS

CYLINDERS

H 2

METHANOGENIC

BIOREACTOR

CO 2

GAS FLOW

CONTROLLERS

BIOGAS

RECIRCULATION

GAS

PREHEATER

HOLLOW FIBRE

MEMBRANE MODULE

SAMPLING POINT

GAS

FILTER

70

75

80

85

90

95

100

0 0.5 1 1.5 2 2.5

Fin

al C

H4

con

cen

trat

ion

(%

v.)

𝐐𝐑𝐂,𝐆/𝐐𝐈𝐍,𝐆

50/5060/4070/30

Initial conc. (CH4/CO2)

4 H2 + CO2 CH4 + 2 H2O

Time (h)

0 50 100 150 200 250 300 350 400

mm

ols

CH

40

2

4

6

8

10

12

14

16Test 1

Test 2

Test 3

Test 4

Test 5 - OCV

Test 11

(Colprim et al. 2015)

-Microbial electrosynthesis (MES)

2. Biorefinery

RECOVER

-Biorefinery

R. Kleerebezem et al. Reviews in Environmental Science and Bio/Technology. (2015)

-Biorefinery

VFA

Bioplastics

Energy

n-Caproate, n-Caprylic acid, etc

Fuels (e.g. butanol) Raw chemicals (e.g. VFA, esters, etc)

[Electrosynthesis]

[Reverse β oxidation]

Chain elongation

[Organic chemistry]

[Organic chemistry]

-Bottlenecks

Selectivity: Obtain certain

VFAs and the desired amount of each one.

Product inhibition: Extract the product to let the fermentation keep going.

-VFA: Why is selectivity important?

Acetate Butyrate Propionate Valerate

PHB PHV

Brittle and stiff P(3HB-co-3HV)

More flexible and tougher

Lee et al.: Chemical Engineering Journal (2013)

-Increasing selectivity

pH

Feeding pattern

Substrate concentration

(co) Substrate

HRT Temp

-Influence of pH on selectivity

Temudo, M.: Appl. Microbiol. Biotechnol. (2008)

0

10

20

30

40

50

60

70

80

90

35 °C 45 °C 55 °C

%

Acetate

Propionate

Butyrate

Valerate

Jiang et al. Bioresource Technology 2013)

-Influence of T on selectivity

-Effect of Electrochemical coupling and HRT

Zhang et al.: Bioresource Technology (2015)

-Thermodynamic-based Model for Products Yielding

Prediction

Hypothesis: The species able to harvest more energy in the imposed conditions will dominate the process.

-

39-

Gonzalez-Cabaleiro et al. Plos One (2015)

-Acidogenic Fermentation.

pH

-

38-

Butyrate

Acetate

Ethanol

Product Yield

Propionate

Gonzalez-Cabaleiro et al. Plos One (2015)

- VFA continuous removal

Ludo Diels (VITO, Belgiumi. http://www.water4crops.org

-VFA Removal Technology: Electrodialysis

Reduced 1500 mg/l VFA (acetic, propionic, butyric & valeric) by up to 99% in 60 minutes.

Jones et a. Bioresource Technol. (2015)

-In Situ Product Recovery (ISPR)

0

2

4

6

8

10

Without ISPR With ISPR

Pro

du

ctiv

ity

(g/L

·h)

Succinate (Cell recycle +mono+-polar ectrodialysis,Meynial-Salles, 2008)

Lactate (Electrodialysis, Min-tial, 2004)

Lactate (Electrodialysis, Min-tial, 2005)

ABE (Gas stripping, Xue, 2013)

ABE (Gas stripping, Ezeji 2003)

Van Hecke et al.: Biotechnology advances 2014

- Wastewater to Bioplastics

Step 1. Natural Selection

STRATEGY: Feast-Famine regime

Enrichment reactor

PHA production during the feast

phase

PHA consumption during the famine

phase

Very fast substrate uptake

DO profile

Step 2. PHA production

Time [h]0 5 10 15 20 25 30

Biop

last

ic [w

t%]

0

20

40

60

80

100

80 wt% Bioplastic

-Wastewater to Bioplastics

-Pilot plant of PHA (Aquiris. Brussels)

-Pilot plant at Mars chocolate. Veghel (NL)

- Production at industrial location at

1 kg/day scale

- Reactor volumen: 300 L.

- The production has to be optimized

to bring down the production costs

of currently about 8 euro/kilogram to

2 euro/kilogram.

Princess Aurora

Maleficent

-The sleeping beauty…

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1981-85 1986-90 1991-95 1996-2000 2001-05 2006-10 2011-15

… and the Prince

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1981-85 1986-90 1991-95 1996-2000 2001-05 2006-10 2011-15

Who is the Prince?

-Sustainability -Resource recovery

-Anammox -..............

Brilliant future !!

-The A(co)D team

Juan M. Lema Marta Carballa Jorge Rodríguez

Iván Rodríguez

Alberte Regueira Antón Taboada

Leticia Regueiro Rebeca González

Lorena González

Santiago García

Chiara Pedizzi

-The (bio) Group USC

Great Opportunities for

Anaerobic Digestion

Juan M. Lema

Department of Chemical Engineering

University of Santiago de Compostela, Spain

Castelló, 7 de julio de 2016