2011 International Conference on Alternative Energy in Developing Countries and Emerging Economies
- 74 -
A. Emulsified Oil
An emulsion is a mixture of two or more immiscible
liquids which could be merged by some kind of
surfactant. One liquid (the dispersed phase) is
dispersed in the others (the continuous phase).
The surfactant is also called
emulsifier
and in this
study the surfactant is 1 % by volume of Sorbitan
monooleate (C
24
H
44
O
6
). The blending was performed
by agitating the mixture having 1,000 liter in a tank
with an agitator speed of 1,500 rpm for 10 minutes.
Fig. 1 shows the structure of emulsified oil and Fig. 2
shows the stability of the emulsion after blending. The
heating value (LHV) and other properties of the
emulsified oils are also shown in Table I.
TABLE
I.
P
HYSICAL PROPERTIES OF FUELS
.
Fig. 1. The structure of emulsified oil (Diesel/CPO/Water 90/5/5 ).
The magnification of eye piece is 10
x.
Fig. 2. The emulsion after blending. The composition was
Diesel/CPO/water 90/5/5.
In general, the heating value of the blended
diesel/CPO was slightly lower than that of the diesel oil
but the viscosity of the blended oil was higher. When
water was merged with the blended oil in the form of
emulsion, the viscosity was less with the content of
water.
Surfactant was used to merge water with oil in a
form of emulsion as shown in Fig. 1. The water
droplets of about 6 micron were coated with small oil
droplets. However, there was instability in mixing after
a period of time. It could be noted that there were some
deposits after time lapse about 5 min after mixing.
Anyhow, the emulsion could be recovered immediately
after shaking the mixture. Fig. 2 shows the stability of
the emulsion after blending.
B. Engine Test and Emissions
A four-stroke single cylinder diesel engine having a
precombustion chamber with a maximum power of 7.5
hp at 2,200 rpm and the cylinder volume of 437 cm
3
was running with the tested fuels.
The engine
specification is shown in Table II.
TABLE
II.
T
HE ENGINE SPECIFICATION FOR DIESEL FUEL
.
Fig. 3. The engine test bed
.
Fuel
Heating
Value
(kJ/kg)
Density
(kg/m
3
)
Viscosity
(cst @
40ºC)
Diesel
45,297
826
2.93
Diesel/Water (95/5)
44,274
832
2.98
Diesel/Water (90/10)
42,538
846
3.028
Diesel/CPO/water
(90/5/5)
43,249
838
3.96
Diesel/CPO/water
(85/5/10)
41,850
844
3.52
Diesel/CPO/water
(85/10/5)
42,394
842
4.48
Diesel/Palm/water
(80/10/10)
41,611
848
4.14
Engine Type
4-stroke,
horizontal
cylinder with water cooling
No. of cylinder
1 with a precombustion
chamber
Cylinder Size
x Stroke Length
(
mm x mm
)
80 x 87
Cylinder Capacity
(
liter
)
0.437
Peak Power
7.5 hp or 5.52 kW at
2,200 rpm
Max. Torque
2.70 kg-m at 1600 rpm
Specific Fuel Consumption
195
Compression Ratio
23 : 1
Degree of Oil Injection
(
degree
)
13 degree
(
before top dead
center
)
Oil Injection Pressure
(
kg/cm
2
)
120
6
P
m
