Seedling stages Life Cycle Inventory LCI on Jatropha curcas
The bean of Jatropha curcas consists of 60 percent of weight kernels fruit pulp and 40 percent of the skin weight. Nucleus seed kernel of jatropha oil
contains about 40-45 percent oil that can be extracted by mechanical or solvent extraction such as hexane. Jatropha oil is a type of oil that has triglyceride
composition similar to peanut oil. Unlike Jatropha Kaliki ricinus communis, the essential fatty acids in jatropha oil is high enough so that jatropha oil can be
directly consumed as long as the poison content such as phorbol ester and curcinishad been removed. Jatropha curcas oil is denser than other vegetable oil.
Two methods that are commonly used in mechanical pressing are hydraulic pressing and expeller pressing. Hydraulic press is pressed by pressure around
140.6 kgcm. The amount of used pressure will affect the yield of Jatropha curcas oil. In hydraulic pressing, prior to pressing, jatropha needs pretreatment such as
cooking to coagulate protein. Protein clumping is needed for efficient extraction. Hydraulic press is generally produced oil yield up to 30 percent. Figure 3.35
shows the flow diagram of Jatropha curcas oil extraction method using hydraulic presses. The complete diagram along with the equipment is shown in Appendix 7.
Figure 3.35 Jatropha curcas oil extraction using hydraulic pressing Oil pressing technique using screw is a more advanced technology and
widely used in the oil processing industry today. In this method, the beans are pressed using screw press that runs continuously. This extraction technique does
not require pre-treatment. Dry jatropha beans can be directly inserted into screw press. The screw press can be a single screw pressor twin screw press. Yield of
jatropha oil produced by single screw pressing techniques is approximately 25-35 percent, while the technique of twin screw press produces approximately 40-45
dry Jatropha curcas bean heating with dry vapor 100
o
C to inactivate lipase enzyme and easy to open the bean during milling process
crushing the skin and the bean separate the skin and the flesh
the skin of bean
milling the flesh Hydraulic pressing
hand traditional pressing can yield 25-40 oil Crude Jatropha curcas Oil CJCO
produce clean oil with yellow gold color kernel cake
the oil content is about 5
percent. Figure 3.36 shows the pressing process flow diagram using screw pressing method. The complete diagram along with the equipment is shown in
Appendix 8.
Figure 3.36 Jatropha curcas oil extraction using screw pressing
Figure 3.37 Oil extraction flow chart from Jatropha curcas beans under combination method of twin screw press and solvent extraction
Mechanical pressing technique can also be combined with solvent extraction technique. Although it results good quality, especially when using
solvent extraction method, the production cost is very expensive. So the combination method of pressing and solvent extraction is not suitable for small
and medium industries. This combination of techniques is more appropriate for large industries. Figure 3.37 presents oil extraction flow chart from jatropha beans
under combination methods.
The advantages on using screw pressing are as follows :
seed of Jathropa curcas pressing
cake
filtration pure of CJCO
dry of Jatropha curcas
bean screw pressing
CJCO 30 - 35
kernel cake
Jatropha curcas oil 8 - 10
Solvent extraction solvent by heksanheptana
kernel cake
destilation solvent
crude jathropa curcas oil CJCO
- Production capacity increases due to continue pressing process. - Saves time because the production process does not require pretreatment, i.e.size
reduction and cookingheating. - Increase yield