New Techno-economic Assessment of Microalgae Biodiesel 2 days ago · Techno-economic Assessment of Microalgae Biodiesel Hassan I. El-Shimi Associate Lecturer Chemical Engineering

Techno-economic Assessment of

Microalgae Biodiesel

Hassan I. El-Shimi

Associate Lecturer

Chemical Engineering Department, Cairo University, Egypt

Email: [email protected] Phone: +2 01118087862

Wednesday March 2nd, 2016

The1st International Conference on

Applied Microbiology

entitled

Biotechnology and Its Applications in the Field of Sustainable

Agricultural Development

March 1 - 3, 2016 Giza, Egypt

mailto:[email protected]

http://www.google.com.eg/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0CAcQjRw&url=http://www.symbols.com/symbol/1577&ei=rqLxVKXxMczxUr6Dg8gD&bvm=bv.87269000,d.d24&psig=AFQjCNHoysvMelD8GJmPJVkY8xoj64ZRtA&ust=1425208290033219

Introduction

Why make algae a fuel?

Research Objectives

Experimental Work

Results

Conclusions

Acknowledgement

References

2 El Shimi, H.I. 1st Applied Microbiology Conf. Egypt, March 2016

Introduction

Ever-increasing of energy incentives the scientists to

search and develop renewable energy sources such

as biofuels.

Liquid biofuel is the unique alternative for

transportation fuel, while solar and wind energy is

better to utilize in electricity production.

Algal biodiesel is a technically attractive alternative

and renewable diesel fuel without excessive engine

modifications.


Why make algae a fuel?

Microalgae can be cultivated in domestic

wastewater (1m3 of wastewater is

required to produce 800 g of dry algae).

Microalgae reduce emissions of a major

greenhouse gas (1 kg of algal biomass

requiring about 1.8 kg of CO2).


Biodiesel from Algae

doesn’t conflict with the

food crisis.


Microalgae reproduce themselves every few days.

High oil productivity (1000-6500 gallon/acre/year)

Oil yield exceed 10x the yield of the best oilseed crops.


Research Objectives


Biodiesel Production from Algae

Direct Transesterification of

Algal Lipids into Fatty acid

Methyl Esters (Biodiesel)

without Pre-extraction of Algal

Oil.

Extraction of Algal Oil

using Mechanical

Pressing followed by

Chemical Solvent

like Hexane.

Transesterification of

Algal Oil into

Biodiesel.

OR

Chemistry of Transesterification

11

Clean Burning Alternative fuel for diesel engines

Produced from Domestic Renewable Resources: any fat or oil, like vegetable oil, used greases, animal fat.

Meets health effect testing (CAA)

Lower emissions, better lubricity

High flash point (>170oC), Safe to store and burn

Biodegradable, Essentially non-toxic.

Chemically, biodiesel molecules are mono-alkyl esters produced usually from triglyceride esters

Research Objectives

Algal Biomass

CO2 Emissions

Wastewater

Egypt Desert

Highest Algal Biomass

Productivity and Lipids %

Direct Transesterification

Feasibility Study & Algal

Biodiesel

Commercialization


Experimental work

Compounds %

Proteins 61.3

Lipids 11.05

Minerals 6.95

Fibers 4

Moisture 0.5

Carbohydrates 12.8

Nucleic acid 2.5

Spirulina-platensis

Materials

Microalgae were supplied from

Microbiology Department, Agricultural

Research Centre, Giza

Chemicals

Methanol CH3OH (99.9 % purity)

Sulphuric acid H2SO4 as a Catalyst (98% purity)

Hexane C6H14 for Decantation

Distilled H2O

All chemicals were purchased from El-Nasr

Pharmaceutical Chemicals Co. Egypt.


Equipment


Reactor

"Acidic

Methanol"

Obtain water layer:

glycerol + catalyst

+ excess methanol

Filtrate solution:

Biodiesel + Glycerol

+ Catalyst +

Methanol +

Unreacted Oilgae Water

Glycerol

Biodiesel

Microalgae

Powder

Algal cake

Hydrophobic

layer: hexane +

biodiesel +

unreacted

Oilgae

Filtration

over sodium

sulphate

Evaporation

Filtration

Generation

of two

layers

Methanol

Evaporation

Hexane

Direct Transesterification


Alcohol/Oilgae

(wt./wt.)

Reaction

Time

Catalyst

Concentration

Temperature

Agitation

Mode

Biodiesel

Crude

Glycerol

Filtration


Results

Component Value Unit

Carbohydrates 12.6 %wt

Protein 51.5 %wt

Moisture 1.5 %wt

Ash 7.5 %wt

Ca 400 mg/100 g algae

P 900 mg/100 g algae

Fe 70 mg/100 g algae

N 500 mg/100 g algae

K 1475 mg/100 g algae

Valid as a bio-fertilizer

Algalcake

The predominant fatty acid was the palmitic acid C16:0

(49.58% by mole), which makes the oil a promising

feedstock for biodiesel fuel synthesis.

Algal Oil

Fatty acid Spirulina Jatropha

Mystic (C14:0) 22.67 0

Palmitic (C16:0) 49.58 18.22

Palmitoleic (C16:1) 2.75 1.2

Stearic (C18:0) 5.56 5.14

Oleic (C18:1) 2.24 28.46

Linoleic (C18:2) 5.03 48.18

Linoleuic(C18:3) 7.41 0

Ecosanoic (C20:0) 1.06 0

Eicosenoic (C20:1) 3.69 0

Saturated 78.87 23.36

Monounsaturated 8.68 29.66

Polyunsaturated 12.44 48.18

Avg. Mwt. 845 Nil

900

500

1475

The acid value and viscosity of Oilgae were too much; 37.4 mg KOH/g and 58 cp,

respectively. Therefore the choice of acidic over alkaline catalysis for the direct

transesterification process was justified.


Variables affecting the direct

transesterification

1. Effect of Alcohol/S.platensis mass ratio

Temperature: 65oC

Time: 8 hr

Catalyst conc. 100% wt.

Stirring: 650 rpm

73.2

81.79

84.7 84.7

y = 2E-07x3 - 0.0004x2 + 0.261x + 27.9

R² = 1

72

74

76

78

80

82

84

86

0 100 200 300 400 500 600 700

Alg

al

bio

fue

l c

on

ve

rsio

n (

%)

Methyl alcohol/S.platensis mass ratio

The studied range of methanol/feedstock mass ratio was: 267/1 – 667/1 that equivalent

to 40-120 ml for each 1g algal biomass.

No significant increase in algal biodiesel is reported above 533/1.

The H2SO4 load was

optimized to be 100%

(wt/wt oil); where further

increase had not

improved the process

efficiency .


2. Effect of Reaction Time and Temperature

Time, hr Yield %

27 oC 40 oC 50 oC 65 oC

2 1.35 25.11 38.2 43.1

4 10.62 45.81 70.5 76.22

8 30.22 62.3 81.54 84.7

10 34.71 62.512 81.63 84.82

To investigate the influence of

reaction time (2, 4, 8 and 10 hr) and

temperature (27, 40, 50 and 65C), a

methanol volume of 80 ml, 100% by

mol. catalyst conc. and continuously

stirring the reaction at 650 rpm

conditions were used.

The fact that the elevated temperatures (and pressures)

improved the initial miscibility of the reacting species,

leading to a significant reduction in the reaction times.


2. Effect of Reaction Time and Temperature

1.35

10.62

30.22

34.71

25.11

45.81

62.3 62.512

38.2

70.5

81.54 81.63

43.1

76.22

84.7 84.82

y = -0.1992x2 + 6.706x - 11.849

R² = 0.9955

y = -0.8537x2 + 14.809x - 0.6505

R² = 0.9979

y = -1.342x2 + 21x + 3.703

R² = 0.973

y = -1.375x2 + 21.09x + 8.884

R² = 0.978

0

10

20

30

40

50

60

70

80

90

100

0 2 4 6 8 10 12

Bio

die

se

l C

on

ve

rsio

n (

%)

Reaction Time (hr)

27C

40C

50C

65C


When the in situ

transesterification process

was conducted without

stirring, no reaction will be

obtained, and the equilibrium

conversion of the microalgae

oil content to biodiesel is

zero.

3. Effect of Stirring

0

10

20

30

40

50

60

70

80

0

58.7

76.22

Yie

ld %

No stirring

Stirred intermittently (1 h off, 1 h on)

Stirred continuously

Process conditions:

15g biomass, 80ml

methanol, 100% H2SO4

conc., at 65 C for 4 hrs.

Because 87% of the equilibrium FAME conversion was

achieved after 1 h with continuous stirring under the

experimental transesterification conditions.


Quality Assessment of Algal Biodiesel Property Unit Petroleum diesel Algal biodiesel Biodiesel (EN 14214)

Carbon range C8-C16 C12:0-C22:0 C14:0-C20:2

Density at 15oC g/cm3 0.83-0.84 0.864 0.86-0.90

Viscosity at 40oC cSt 1.2-3.5 5.2 3.5-5.0

Acid number mg KOH/g oil 0.023 0.75 <0.5

Pour point oC -15 to -3 -12 -

Cloud point oC -15 to +5 -3 -4

Flash point oC 60-80 189 >101

Aniline point 67 84

Distillation range oC 157-325 270-403 -

Auto-ignition point oC - - -

Water content ppm 52 39 <500

C %wt 87 76 -

H2 %wt 13 <12.7 -

O2 %wt 0 >11.3 -

S %wt 0.13 Nil <0.01

Calorific value MJ/kg 45.9 41 32.9

Cetane number 50 70 >51

Paraffins %wt - 79 (avg.) -

Olefins %wt - 20 (avg.) -


26

Algal Biodiesel Economics 2016

Economic assessment of algal biodiesel project

The feedstock is Nannochloropsis sp. of 44%wt lipid content.

The biomass cost is assumed to be $400/ton , and algal biodiesel price is suggested to be

$2500/ton.

The production capacity of algal biofuel is 0.5 million tons/year.

Operating hours based on three shifts (8h) per day and 300 working days per year.

The storage capacity is suggested to be only one week for raw materials and products.

The catalyst (H2SO4 conc.) will be supplied by Egyptian Armed-Forces Plants ($1250/ton).

Glycerin and algalcake are co-products that help to minimize the annual production cost.

Algalcake price is suggested to be $300/ton, whatever its utilization purpose as bio-fertilizer or

solid biofuel

80% of methanol is assumed to be recovered.

Depreciation estimated using straight line method for 15 years life span and the scrap value is

estimated to be 10 % of equipment cost (EC).

Electricity cost is $0.1/kWh, and the electricity consumption is assumed to be 70kWh/ton algal

biodiesel .

Working capital investment (WCI) is represent 20% of fixed capital investment (FCI); as the

products are not require marketing heads

10% of gross earnings is accounted for taxes expenses.

Assumptions


Quantity (ton/yr) Unit cost ($/ton) Cost ($/yr)

Raw materials

Algal biomass 1341633.6 400 536653429.2

Methyl alcohol 1431075.8 440 62967335.7

H2SO4 catalyst 590318.8 1250 737898465.1

1337519230

Revenues

Biodiesel 500000 2500 1250000000

Glycerin 50000 750 37500000

Algalcake 841633.6 300 252490072

1539990072

Raw materials and revenues cost


Equipment Unit No. Total cost ($)

Algae storage tanks (300 m3) 89 6675000

Belt conveyor 10 220000

Methanol storage tanks (200 m3) 142 7100000

H2SO4 storage tanks (200 m3) 59 2950000

Mixing vessels (100 m3) 57 1425000

Transesterification reactors (Jacketed & Agitated 100 m3) 95 28500000

Mixers (Propeller, 10 hp) 57 570000

Decanters/Centrifuges (bottom driven 3m diameter) 10 370000

Pumps (progressive cavity type, 30gallon/min) 20 220000

Extraction/Distillation columns ( 2m Diameter,20m Height) 38 19000000

Algal biodiesel storage tanks (200 m3) 50 2500000

Glycerin storage tanks (100 m3) 10 250000

Filters (Hydrocyclone, 1m diameter, 25-50 m3/h) 8 400000

EC 70180000

Equipment cost (EC)


Capital investment category Cost ($)

Equipment cost (EC) 70180000

Equipment delivery cost 7018000

Installation cost 14036000

Piping 14036000

Buildings 7018000

Utilities 10527000

Instrumentation & Control 10527000

Site Development 7018000

Auxiliary buildings 3509000

Design and Eng. 28773800

Contractor' fee 28773800

Contingency 14386900

Legal expenses 14386900

FCI 230190400

WCI 46038080

TCI 276,228,480

Capital investment (CI)


Unit cost (US$) Cost ($/yr)

Direct Production Cost (DPC)

Raw Materials 1337519230

Miscellaneous materials 10% M&O 701800

Electricity $0.1/kWh 3500000

Maintenance and operational cost (M&O) 10%EC 7018000

Operating labor $13500/employee/year 2800000

Depreciation Striaght-line depreciation 4210800

Plant overheads 50% of labor and M &O 4909000

Interest 2% EC 1403600

Property insurance cost 5% EC 3509000

Indirect Production Cost (IPC)

Research and Development 5% of DPC 68278571.5

General expenses 25% of labor and M&O 2454500

Contingency

10% of labor, M&O and plant

overheads costs 1472700

ABC 1437777202

ABC/ton biodiesel 2875.5

Algal biofuel cost (ABC)


Techno-economic indicators for algal biofuel production

based on the appreciated assumptions Item Value

Raw materials ($/yr) 1,337,519,230

Revenues ($/yr) 1,539,990,072

Total capital investment ($) 276,228,480

Total production cost ($/yr) 1,437,777,202

Net profit ($/yr) 91,991,583

ROR (%) 33.3

Pay-back time (yr) 2.4

Selection of microalgae strain

Algae lipid productivity and fatty

acid profiles that matching the

biofuel requirements are generally

used to select the appropriate

strain, however lipid content is of

great importance criteria for algal

biodiesel business.

For profitable algal biofuel

business, lipids content cannot less

than 37.3%; to get US$ 55245674

net profit and 3.8 years a payback

time.

0

1

2

3

4

5

6

-80

-60

-40

-20

0

20

40

60

0 20 40 60 80

Pay-b

ack p

eri

od (years

)

RO

R (%

)

Microalgae lipid (%)

ROR Pay-back period

Algae specie Oil %wt

Nitzschia sp. 45-47

Neochloris oleoabundans 35-54

Nannochloropsis sp. 31-68

Botryococcus braunii 25-75

Schizochytrium sp. 50-77


Conclusions

Algal biofuel is interested in recent years; due to the unique benefits of microalgae

Oilgae extraction is one of the most costly processes which can determine the sustainability

of microalgae-based biodiesel. However, it is necessary to evaluate Oilgae properties and

determine the appropriate method for biofuel production.

The existence of C16:0-C18:3 in algal oil making it a promising feedstock for green fuel

production, but the high viscosity (58cp) and excessive FFA (~18%) resists its direct use as

a fuel

Direct transesterification (or in-situ) process integrates oil extraction and its conversion into

biodiesel in a single step; hence it minimizes the total manufacturing cost. Results reported

that methanol/Spirulina platensis mass ratio of 533/1 is recommended to be ideal; to yield

84.7% of algal biofuel at 65oC, 100% catalyst concentration and 8h with experimental error

of ±3.5%.

Biochemical analysis of algalcake proved its utilization as a bio-fertilizer, animal fodder, solid

biofuel, or a feedstock for bioethanol production according to economics view point.

Quality assessment of algal biodiesel confirm EN 14214 standards.

Preliminary economic analysis of algal biodiesel project show that TCI is US$ 276228480,

annual ABC is US$ 1437777202, annual net profit is US$ 91991583, ROR is 33.3% and

payback time is 2.4 yr for production capacity of 0.5Million tons based on algae lipid content

of 44% (Nannochloropsis), feedstock cost of US$400/ton and algal biofuel selling price of

US$2500/ton.

To obtain a profit, the algae oil content cannot be less than 37.3%.


Acknowledgements

The author would like to express his appreciation to the

Faculty of Engineering, Cairo University, Egypt for the

technical and financial support.

References

Are available in the conference proceedings.

37

Documents

New Techno-economic Assessment of Microalgae Biodiesel 2 days ago · Techno-economic Assessment of Microalgae Biodiesel Hassan I. El-Shimi Associate Lecturer Chemical Engineering