Production of Bio-Diesel Using Vegetable Oils

P M V SubbaraoProfessor

Mechanical Engineering Department Indian Institute of Technology Delhi, New Delhi

Maximize Yield & Quality ….

Characterization of Derived Bio-resources

• Pongamia oil

• De-oiled cake

• Shells

Straight Vegetable Oil Chemistry

C63 H122O6

Straight Vegetable Oil Chemistry

• The molecular formula is a triglyceride molecule that contains multiple Carbon double bonds.

• A molecule with multiple Carbon double bonds tends to be more reactive under heated conditions than a molecule containing fewer or no double bonds.

Metathesis reactions for Molecular Cracking

Also called Double-replacement reactions.

The Reaction

• The alcohol reacts with the fatty acids to form the mono-alkyl ester (or biodiesel) and crude glycerol.

• The reaction between the biolipid (fat or oil) and the alcohol is a reversible reaction so the alcohol must be added in excess to drive the reaction towards the right and ensure complete conversion.

• In general a titration is carried out to find out how much alkaline is needed to completely neutralize any free fatty acids present, thus ensuring a complete transesterification.

• Empirically 6.25 g/L NaOH produces a very usable fuel.

• One uses about 6 g NaOH when the VO is light in colour and about 7 g NaOH when it is dark in colour.

ReactorMixture

Vegetable oil

Methanol

NaOH

Water washing

BiodieselPure Biodiesel

Water removal

Separator

Glycerol Crude Biodiesel

CondenserWater in Water out

Methanol Recovery

Block diagram of the base catalyzed transesterification process of vegetable oil

Mid-sem PresentationBy

Sanjib Kumar RoyMechanical Engineering,

IIT Delhi

Motor

Heater

Thermostat

Temperature indicator

Stand

Oil+Alchohol+

NaOH

Water

Biodiesel

Water

Heater

Air

Valve

Water

Diagram of the Small Capacity biodiesel Reactor

Mid-sem PresentationBy

Sanjib Kumar RoyMechanical Engineering,

IIT Delhi

Dept of Mechanical Engg.,IIT Delhi

Biodiesel reactor (~1000 ml capacity)

BIODIESEL REACTOR

Mid-sem PresentationBy

Sanjib Kumar RoyMechanical Engineering,

IIT Delhi

Separating unit : Jatropha Bio-diesel

Mid-sem PresentationBy

Sanjib Kumar RoyMechanical Engineering,

IIT Delhi

Water washing of biodiesel

Mid-sem PresentationBy

Sanjib Kumar RoyMechanical Engineering,

IIT Delhi

Dept of Mechanical Engg.,IIT Delhi

Effect of the sodium hydroxide (NaOH) on biodiesel yield and viscosity

50

60

70

80

90

100

2.00 2.08 2.16 2.24 2.32 2.40Sodium hydroxide(g)

% B

iod

iesel

yie

ld

3

3.5

4

4.5

5

5.5

6

Vis

co

sit

y, c

St

YieldViscosity

Mid-sem PresentationBy

Sanjib Kumar RoyMechanical Engineering,

IIT Delhi

Effect of methanol quantity on biodiesel yield and viscosity

0

20

40

60

80

100

20 30 40 50 60 70 80 90 100 110

Methanol (ml.)

% B

iod

iesel

yie

ld

3.0

3.5

4.0

4.5

5.0

5.5

6.0

Vis

co

sit

y, c

St

YieldViscosity

Temperature(oC)

Base (g)

Methanol (ml)

Time (hr)

Viscosity (cSt)

% Yield

65 2 72 2.5 3.70 99

Corrected optimal values by changing the reaction time

20

40

60

80

100

0 1 2 3 4 5

Reaction time in hours

yield

of b

iodi

esel

in %

OPTIMAL VALUES FOR BIODIESEL PRODUCTION

22.5

33.5

44.5

5

0 1 2 3 4 5

Reaction time in hours

visco

sity i

n sq

uire m

m/s

VISCOSITY TESTING FOR KARANJA,BIODIESEL AND DIESEL

S no Name of the oils

Quantity(ml)

Temperature

(0c)

Time

(sec)

Viscosity(cst)

Remarks

1 Karanja oil

100 40

60

80

198

122

93

20.5

13.2

10.0

With increase of temperature ,viscosity decreases and more bright and lighter

2 Bio-diesel

100 40

60

80

48.5

41

36

5.2

4.4

3.8

Darkness decrease in increase of temperature

3 Diesel 100 40

60

80

46

36

34

4.9

3.83.6

More bright in increase of temperature

Measurement of Calorific Value : Bomb Calorimeter

Comparison of Properties of Bio-diesel, Diesel and karanja oil.

S/no Name of oils

CV

Mi/kg

Viscosity at 400c

(cst)

Specific gravity

(mg/ml)

Flash point (0C)

Fire point (0C)

Cloud point (0C)

Pour point (0C)

1 Karanja oil

36.00 20.18 0.921 230 270 _ _

2 Bio-diesel 38.02 4.7 0.875 185 225 21 8

3 Diesel 43.47 4.2 0.825 135 150 _ _

Comparison of Properties of Bio-diesel, Diesel and Jatropha oil.

S/no Name of oils CV

Mi/kg

Viscosity at 400c

(cst)

Specific gravity

(mg/ml)

Flash point (0C)

Fire point (0C)

1 Jatropha oil

39.66 14.6

0.905 209 326

2 Bio-diesel 36.29 4.06 0.865 185 217

3 Diesel 43.47 4.2 0.825 135 150

Comparison of Properties of Bio-diesel, Diesel and Linseed oil.

S/no Name of oils

CV

MJ/kg

Viscosity at 400c

(cst)

Specific gravity

(mg/ml)

Flash point (0C)

Fire point (0C)

1 Linceed oil 39.20 29.4 0.903 231 244

2 Bio-diesel 40.13 3.85 0.850 163 176

3 Diesel 43.47 4.2 0.825 135 150

Comparison of Properties of Different Bio-diesels.

S/no Name of oils

CV

MJ/kg

Viscosity at 400c

(cst)

Specific gravity

(mg/ml)

Flash point (0C)

Fire point (0C)

1 Linceed 40.13 3.85 0.850 163 176

2 Jatropha 36.29 4.06 0.865 185 217

3 Karanjia 38.02 4.7 0.875 185 225

Energy Audit of Sub-Species of Pongamia Fruit Collections : 1ton of Bio-Diesel

• Mass of produce: 6.3 tons (100%).

• Mass of Bio Diesel: 1 ton (16%).

• Mass of cake : 2.15 tons (35%).

• Mass of Shells : 3.15 tons(49%).

• Total Energy value of Bio-diesel: 38 GJ (30%)

• Total Energy value of Cake: 40.8GJ (32.4%)

• Total Energy value of Shells: 47.25GJ (37.6%)