Frank Rogalla

Energy Potential compared to electricity consumption in wastewater Aeration

Electricity 120 g DQO/PE/d x 0,5 kwh/kg = 0,06 kwh/PE / d

Energy (Spain): 3 x 0,06 x 47 M x 365 = 3 100 M Kwh / yr

Wastewater Sludge

50 g MV / d x 47 M PE x 365 = 860 M t / yr

Biomethane CH4

0,9 Nm3 / kg MV el * 0,5 *0,65 * 10 kwh/m3= 3 kwh/kg

Total Annual Potential = 2 500 M kwh

Improving Energy Recovery in conventional WWTP High rate first stage to adsorb easily digestible organic matter

(SRT = 12 h) and improve biogas production

Maximize the efficiency of cogeneration (38 %)

Optimize activated sludge aeration for nitrogen removal, with continuous measurements of oxygen and ammonia .

Reduce the impact sludge returns

by low energy anammox process - deamonification

Reference: Wett B., Buchauer K. and Fimml C. (2007).

Energy self-sufficiency as a feasible concept for wastewater treatment systems,

Institute of Infrastructure and Environmental Engineering, University of Innsbruck, Austria.

Optimization of Conventional WWTP:

Example of plant in Strass, Austria: From 49 % energy self-sufficiency in 1995 plant achieved 108 % in 2005 Reference: Wett B. (2006). : Solved upscaling problems for implementing deammonification

of rejection water, Wat.Sci. & Tech, Vol. 53, No. 12, pp 121-128.

Anammox pilot plant in Vigo USC + Aqualia

Agujeros en las tapas

Analizador de NO2

Controlador

SC1000

Bomba vaciado

Reactor semicontinuo

2x Sondas NH4

Variador de frecuencia (agitador)

Día 23

Día 242

Primary Settler

Wastewater

Effluent

Primary sludge thickener

Anaerobic Digester

Biogas

Drum thickener

Anoxic Aerobic

Activated sludge system

Dewatering Centrifuge

Dewatered Sludge

Secondary Settler

Wastewater line

Sludge line

Pumping

Grit and grease removal

Screening

ELAN reactor

Struvite Cristallizer

Efluente Municipal Típico /PE

Value of wastewater per person equivalent (PE)

200 l x 0,5 € / m3 = 0.1 €

Organic Bioenergy 60 g DBO =

0,12 kg DQO x 0,7 x 0,35 m3 CH4/ kg

x 10 kwh / m3 CH4 x 0.1 € / kwh = 0.02 €

12 g TN x 660 €/t N= 0.008 €

2 g P x 2000 €/t P = 0.004 €

Bio-fuels: Spains annual consumption vs. total biogas potential in WW

Consumption at Gas Stations

Bioetanol 362 kt

Biodiesel 1.350 kt

Total 1.7 M t x 11.630 Kwh /t= 19 771 M Kwh/yr

Bio-methanisation

120 g DQO / P / d x 0,7 x 0,35 m3 CH4/ kg x 10 kwh / m3 CH4 = 0,5 kwh / PE / d

0,5 kwh x 47 M hab x 365 dias = 8 600 M Kwh /yr

EU FP 7 Call Biofuels from Algae

Info Day 14.11.2009

Deadline 04.03.2010

Large Scale Demo: 10 h

Full industrial plant -

from biomass production

to fuel processing

and fleet demonstration

Productivity > 90 t/ha/yr

No CO2 from fossil fuels

14 Proposals reviewed (20 submitted) = Total Cost 157 M€

21 M € for 3 shortlisted projects (50 % funding)

Kick-Off 10.05.11

Small scale facilities for PBR Evaluation

Sea water 220 L airlift tubular photobioreactor Phaeodactylum tricornutum 19.000 L oil /ha·year (Acien-Fernandez, 1998)

Sea water 110 L flat panel photobioreactor Nannochlropsis sp. 23.500 L oil /ha·year (Rodolfi et al., 2009)

Typical biomass productivity 0.035 kg m2 d1 (80 t ha1 yr1) Maximum biomass concentration 2.0 kg m3 (1.0 kg m3 typical)

Typical biomass productivity 0.050 kg m2 d1 (100 t ha1 yr1) Maximum biomass concentration 3.0 kg m3 (1.5 kg m3 typical)

Energy Requirements of PBR

750 (35 t / ha / yr)

< 10

Biomass Energy 22 kj/kg = 6 kwh /kg

Chlorella, Japan

Spirulina, CA

-carotene, Australia

Astaxanthin, Hawaii

Existing biomass production methods

Typical productivity

10 g m2 day1

(30 tons ha1 year1)

Compared to Spirulina Production

To yield 25,000 l oil/ha/year (for 25 % oil in algae)

@ cost of US$ 200/barrel = 1 € / l

(today´s oil price US$ 100/barrel):

– Productivity increase > 3 X (from 10 g/m2/d)

– Production cost decrease > 5 X (Nutrients 30 %)

40 ponds x 2900 m2 = 11.6 ha

Influent

Conventional Wastewater Treatment vs

Integration of Anaerobic Pre-Treatment

Preliminary Treatment

Primary Sedimentation

Tank

Effluent Activated Sludge

Sludge Disposal

Dewatering

Thickener

Digester

Biogas

Anaerobic Process

Biogas

Effluent Algae Pond

Dewatering

Fertiliser

Waste biomass

Disintegration of solids

New Wastewater Treatment Flowsheet ? Value Creation instead of Waste Production …

Large Scale UASB Experience

• Belo Horizonte, MG: 1,700,000 PE

• 155 000 m3/d ( first phase)

• 24 modules of 2200 m3 each

• Planned Secondary Treatment

• with Trickling Filters

Courtesy of – por gentileza de: Copasa http://www.copasa.com.br/cgi/cgilua.exe/sys/start.htm?sid=160

Integral use of biomass: A potential concept

Hidrolysis Wet

biomass Extraction Digestion

Waste biomass to boiler

enzymes solvents wastes

Aminoacids PUFA

Biomethane Upgrading

What is in Algae?

20191817161514131211109876543210

1,000,000

950,000

900,000

850,000

800,000

750,000

700,000

650,000

600,000

550,000

500,000

450,000

400,000

350,000

300,000

250,000

200,000

150,000

100,000

50,000

SP

W 0

.20

ST

H 1

00.0

0

C 1

4:0

C 1

5

C 1

6:0

C 1

6:1

C 1

8:1

C 1

8:2

C 1

9 I

S

C 2

0:3

EP

A

RT [min]

µV aw 080908 E4 methyl esters1.DATA

PROTEIN 40 %

FAT 20 %

CHO 24.4 %

FIBER 0.5 %

ASH 15 %

VITAMIN

Vit E (700 g g-1DW)

Vit C (9800 g g-1DW)

LIPID CLASSES (% TFA)

POLAR LIPIDS 50 % MGDG 15 %

DGDG 8 %

SQDG 4 %

PG 5 %

PC 7 %

PE 3 %

DGTS 5 %

PI 3 %

NEUTRAL LIPID 50 %

Algae Extraction Tests with Chlorella Vulgaris

Algae species Extraction solvent

Extraction process

Extraction condition

Total biomas extracted

%Fatty Acids /Cell Dry weight

%FA/CDW in datasheet

Fatty Acid extraction yield (%)

Chlorella V. Ethanol

Stirring 40C

2hours 10.5% 4.52 8 56.5

Chlorella V. Ethanol/ CO2

Percolation

40C 2hours 57 bar

8.5% 3.62 8 45.3

Chlorella V. Ethanol/ CO2

Percolation

40C 4hours 80 bar

8.06% 4.03 8 50.4

Chlorella V. CO2

Extraction

250 bar 0.93% 0.7 8 8.75

Laboratory and

Basic Research

Pilot 6 x 35 m2

Prototype 2 x 500 m2

Demo 10 ha

PHASE I

PHASE II

FP 7 All-gas: Step by Step Upgrading

Microalgae species

Chlorella vulgaris (SAG 211-12)

Botryococcus braunii (SAG 30.81)

Neochloris oleoabundans (UTEX-1185)

Natural Bloom river water downstream from an Urban WWTP

Culturing media

• Combo two fold (Kilham, S. S., Kreeger, D. A., Lynn, S. G., Goulden, C. E. and Herrera, L. 1998. Hydrobiologia. 377 147–159.)

Total Nitrogen: 28 mg N/L

Total phosphorous: 3,1 mg P/L

Preliminary Tests on Urban Wastewater

50 mL microalgae

inocula

1,5 L of culturing media

(WW or Combo)

Preliminary Laboratory Results for Growing Algae with Wastewater

WW DOPADA SIN

OLIGOELEMENTOS

0,0

10,0

20,0

30,0

0 50 100 150 200 250

Tiempo (horas)

mg N/l

CHLORELLA

VULGARIS

BOTRYOCOCCUS

BRAUNII

NEOCHLORIS

OLEOABUNDANS

BLOOM

WW

0,0

1,0

2,0

3,0

0 50 100 150 200

Tiempo (horas)

mg PPO43-/l

CHLORELLAVULGARIS

BOTRYOCOCCUS

BRAUNII

NEOCHLORIS

OLEOABUNDANS

BLOOM

Biomass Lipid

content

Biomass

Productivity

PBR 2000 mL flasks

Temp. 20 ± 2 ºC

10 / 14 h (D/L)

Intensity: 143 μmol m-2s-1

5% CO2 in air 1,25 L/min

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ave

Mean Temp (oC) 12 13 15 17 19 24 25 26 22 20 15 13 18.4

Precip (mm) 50 56 68 35 16 1 1 11 12 44 82 75 451

NUTRIENT RECOVERY:

Operated with fresh water, various wastewaters and effluent from anaerobic reactors (UASB).

Pure CO2 is used as carbon source.

GROWING MICROALGAE:

Able to operate with different depths (usually 0,3 m)

Total volume in operation (6 x 9,6 = 57,6 m3).

HARVESTING TECHNOLIOGY:

Comparison of settler and DAF, with and without chemicals

Algae Biomass productivity:

Continuous mode with both WW and HRT 4 d :

Secondary and UASB: 13-Jun/25-Jul (43 days)

0

100

200

300

400

500

600

700

800

VSS

(mg

/L)

401 402 403

0

100

200

300

400

500

600

700

800

VSS

(mg

/L)

301 302 303

UASB Secondary 28 g m-2 d-1 21 g m-2 d-1

Pilot DAF: from 300…500 mgTSS/l to 4 % DS

DAF Energy = 0,1…0,05 kwh/m3 Compared to Membranes > 0,5 kwh/m3 Centrifuges > 1 kwh/m3

Initiation of the Civil works: 1st August 2013

NUTRIENT RECOVERY

Operate with wastewater and /or effluent from anaerobic reactors (UASB).

Biomass boiler will provide CO2 as carbon source, using waste materials

GROWING MICROALGAE: With depth 0,3 m, total volume in operation is 300 m3

HARVESTING : Optimised DAF; dewatering with centrifuge and solar dryer

FP 7 All-gas Demo Site: Salt Drying Beds near Chiclana.

WWTP Microalgae cultivation

13 t CO2/d ?

25 000 PE

5000 m3/d 28 mg N/L 3,1 mg P/L

3 t biomass/d

1 t biodiesel/d ?

Preliminary Balance of Wastewater Treatment with Algae Production

900 m3 /d

biomethane

Gas Driven Public Buses Madrid: 350, Barcelona: 250 Sevilla: 140, Valencia: 70 Garbage Trucks > 1000 units

750 m3 /d

biomethane

UASB

Energy Balance:

Conventional - 0,5 kwh el /m3

Anaerobic + Algae: + 3 kwh th / m3 = + 1 kwh el / m3

Preliminary Balance for Biofuel Production from Wastewater (5000 = m3/d – 25 000 PE) Biodiesel (30 % Oil ?)

1000 kg / 0,86 kg/l x 365 d/yr = 314 000 l /yr 260 cars x 6 l/100 km x 20 000 km/yr

Biomethane from Algae Residue 900 m3 CH4/d x 365 d/yr = 328 000 m3/yr x 0,65 kg/m3 = 213 000 kg CH4 /yr 213 cars x 5 kg/100 km x 20 000 km/yr

Biomethane from Raw Influent + Solids - 5000 m3/d x 500 mg/l x 0,3 m3/kg = 750 m3/d x 365 d = 274 000 m3 CH4/yr - 274 000 m3/d x 0,65 kg CH4/m3 = 178 000 kg CH4/yr - 178 cars x 5 kg/100 km x 20 000 km/yr

Biofuel Value: Methane - 0,4 €/m3 x 487 000 m3/yr = 195 000 Euro/yr Biodiesel - 0,5 €/l x 314 000 l/ yr = 157 000 Euro/yr

Water Treatment of Equivalent Value to Biofuels:

5500 m3/d x 365 x 0,2 Euro/m3 = 400 000 €/yr Reduced Energy consumption

5500 m3/d x 0,25 kwh/m3 x 365 x 0,1 €/kwh = 50 000 €/yr

Acknowledgements: Cenit Vida

Jesus Barragan and Jose Antonio Perales CACYTMAR (Centro Andaluz de Ciencia y Tecnología Marinas) University of Cádiz

Emilio Molina Grima and Gabriel Acien Dpto. Ingeniería Química, Universidad de Almería

Gracias por su atencion - Questions ?