A review of processing and machinery for Jatropha curcas L. fruits and seeds in biodiesel production: harvesting, shelling, pretreatment and storage

The harvested Jatropha fruits need to be cleaned, dehulled and stored properly as part of the production of Jatropha biodiesel. During processing, the oil yield and quality of the extracted crude oil can be further improved by removing the husks (outer coating) of the seeds before any necessary seed treatment. This report attempts to provide an insight into the major issues of the process from harvesting the Jatropha fruits to the final storage of the seeds and pretreatment of the Jatropha seeds prior to the oil extraction process in production. This report describes a few aspects of the processes including common methods, research and technologies involved so that some improving strategies can be devised. The final part of this report also describes current development trends and the future prospect of Jatropha as a biodiesel. The paper has determined that both the harvest and shelling processes are basically performed manually, especially in rural areas. These activities are time consuming and introduce a high labour cost (80% of the feedstock cost) that can potentially make the Jatropha oil economically uncompetitive. A solution consisting of process mechanisation and mechanical device development are proposed to improve the sustainability of the industry and to meet the increasing world demand. An improvement in oil yield can also be achieved by fruit/seed pretreatment such as drying, shelling and heating. However, improper control may lead to the formation of oxidation products such as free fatty acids which will affect the efficiency of biodiesel production. This is an important sustainability issue which is related to the future development of Jatropha biodiesel

Effect of mixing period, water and sugar on the sesame cracker dough stickiness

Sesame Cracker or Kuih Bijan is a popular traditional Malays snack in Malaysia. The simplest formulation of Sesame Cracker dough includes glutinous rice flour, sugar, and water. In order to reduce the negative effect caused by dough stickiness, the effect of mixing period (3 to 7 minutes), water (41.6 to 45.6%) and sugar (1 to 9%) on dough stickiness of sesame cracker dough were studied using Texture Analyzer and Chen-Hoseney methodologies (i.e. Chen-Hoseney Dough Stickiness Cell). The result obtained showing that the increment of mixing time, water and sugar addition, increased the dough stickiness, work of adhesion/adhesiveness and dough strength/cohesiveness. However, overmixing of dough had led to the decrease of these parameters

Performance study of a Jatropha curcas l. fruit shelling machine for kernel recovery in biodiesel production

The presence of Jatropha shells and husks during the process of oil extraction can affect oil yield and output quality. A shelling machine has been developed at the Universiti Putra Malaysia (UPM) to supersede the time-consuming manual method to remove shells and husks directly from the whole fruits for kernel recovery. The output kernels are in broken forms that ease the oil extraction process. The machine basically consists of cracking rollers, a vibratory sieve as the first stage separator, and a blower as the second stage separator. The performance of the machine was evaluated using five different blower air speeds (3.5, 6.2, 9.5, 12.6, and 13.4 ms-1) and the size of the mesh on the sifter was fixed. The 9.5 ms-1 speed was selected as optimal as the highest separation efficiency of 66.98% could be achieved. The considerations to determine the separation efficiencies included kernel recovery, the percentage of shells and the percentage of husks removed. At the optimal setting, the shell and husk removal achieved 97.17% and 55.21%, respectively, while the kernel recovery achieved 87.88%. A total of 12.12% kernels were lost and most of the losses were kernels in tiny broken form. The results indicated that a further improvement of the machine is necessary with the application of strategies to create highly different physical properties between the kernels and other impurities to enhance the effectiveness of the removal of impurities while maintaining a low kernel loss

Performance evaluation and CFD multiphase modeling for multistage jatropha fruit shelling machine

The study involved performance evaluation of a Multistage Jatropha Fruit Shelling Machine (PI2015701163) which is used to produce Jatropha kernels (oil-rich nucleus) with higher purity by removing both the outer shells of fruits and husks (seeds' coating). The reduction of shells and husks together, which is not commonly practised at the moment, can improve oil yield and quality during oil extraction process in biodiesel production. The shelling machine consists of two cracking unit with each having different roller clearance for different stage of decortications. Every roller was featured with male threads on the surface. The male threads in different rotating directions and speeds can provoke more shearing effect onto the loaded Jatropha fruits. The machine design also deploys multistage separation mechanisms consisting of vibratory sieve and blowers for a purpose to produce cleaner kernels. The designed machine has been tested at different blower air speeds and fruit moisture contents. The optimal air speed and fruit moisture content were found to be 9.8 ± 0.4 m s-1 and around 5.7% w.b. respectively, where the husks could be removed without causing high kernel loss. The overall results show that the designed machine at the optimal conditions was able to remove 99% of shells and 52% of husks while controlling the kernel loss at around 5%. Further, the separation process which applies blower as separation mean has been further analysed using Eulerian Model and Dense Discrete Phase Model (DDPM) in ANSYS Fluent, for a purpose to understand the behaviour of Jatropha fruits' particles under air flow during the separation process. The simulation revealed that some vortices have existed at converging portion or slope end of the designed separator duct due to instantaneous changes of air velocity and pressure. The formation of vortices could change the flowing direction of particles and lengthen the residence time of the particles in the duct. The phenomena were also found able to cause momentum loss of heavier kernel particles, achieving reduction of kernel loss during the separation process. The simulation results have provided a basis to understand the dynamics of multiphase flow. Further, the numerical model makes the study possible to provide a better insight for making a decision along with future developed scaling factor for machine scaled up activity

Factors affecting commencement and cessation of betel quid chewing behaviour in Malaysian adults

<p>Abstract</p> <p>Background</p> <p>Betel quid chewing is a common habit widely practiced in Southern Asian populations. However, variations are seen in the content of a betel quid across the different countries. Factors associated with commencement and cessation of this habit has been numerously studied. Unfortunately, data on Malaysian population is non-existent. This study aims to determine the factors associated with the inception and also cessation of betel quid chewing behaviour among Malaysian adults.</p> <p>Method</p> <p>This study is part of a nationwide survey on oral mucosal lesions carried out among 11,697 adults in all fourteen states in Malaysia. The questionnaire included sociodemographic information and details on betel quid chewing habit such as duration, type and frequency. The Kaplan-Meier estimates were calculated and plotted to compare the rates for the commencement and cessation of betel quid chewing behaviour. Cox proportional hazard regression models were used to calculate the hazard rate ratios for factors related to commencement or cessation of this habit.</p> <p>Results</p> <p>Of the total subjects, 8.2% were found to be betel quid chewers. This habit was more prevalent among females and, in terms of ethnicity, among the Indians and the Indigenous people of Sabah and Sarawak. Cessation of this habit was more commonly seen among males and the Chinese. Females were found to be significantly more likely to start (p < 0.0001) and less likely to stop the quid chewing habit. Females, those over 40 years old, Indians and a history of smoking was found to significantly increase the likelihood of developing a quid chewing habit (p < 0.0001). However, those who had stopped smoking were found to be significantly more likely to promote stopping the habit (p = 0.0064). Cessation was also more likely to be seen among those who chewed less than 5 quids per day (p < 0.05) and less likely to be seen among those who included areca nut and tobacco in their quid (p < 0.0001).</p> <p>Conclusion</p> <p>Factors that influence the development and cessation of this behaviour are gender, age, ethnicity, and also history of smoking habit while frequency and type of quid chewed are important factors for cessation of this habit.</p

The willingness of final year medical and dental students to perform bystander cardiopulmonary resuscitation in an Asian community

Background Despite the importance of early effective chest compressions to improve the chance of survival of an out-of-hospital cardiac arrest victim, it is still largely unknown how willing our Malaysian population is to perform bystander cardiopulmonary resuscitation (CPR). Aims We conducted a voluntary, anonymous self-administered questionnaire survey of a group of 164 final year medical students and 60 final year dental students to unravel their attitudes towards performing bystander CPR. Methods Using a 4-point Likert scale of “definitely yes,” “probably yes,” “probably no,” and “definitely no,” the students were asked to rate their willingness to perform bystander CPR under three categories: chest compressions with mouth-to-mouth ventilation (CC + MMV), chest compressions with mask-to-mouth ventilation (CC + PMV), and chest compressions only (CC). Under each category, the students were given ten hypothetical victim scenarios. Categorical data analysis was done using the McNemar test, chi-square test, and Fisher exact test where appropriate. For selected analysis, “definitely yes” and “probably yes” were recoded as a “positive response.” Results Generally, we found that only 51.4% of the medical and 45.5% of the dental students are willing to perform bystander CPR. When analyzed under different hypothetical scenarios, we found that, except for the scenario where the victim is their own family member, all other scenarios showed a dismally low rate of positive responses in the category of CC + MMV, but their willingness was significantly improved under the CC + PMV and CC categories. Conclusion This study shows that there are unique sociocultural factors that contribute to the reluctance of our students to perform CC + MMV. Keywords Cardiopulmonary resuscitation Mouth-to-mouth resuscitation Basic cardiac life support Asian communit

Factors affecting commencement and cessation of smoking behaviour in Malaysian adults

<p>Abstract</p> <p>Background</p> <p>Tobacco consumption peak in developed countries has passed, however, it is on the increase in many developing countries. Apart from cigarettes, consumption of local hand-rolled cigarettes such as <it>bidi </it>and <it>rokok daun </it>are prevalent in specific communities. Although factors associated with smoking initiation and cessation has been investigated elsewhere, the only available data for Malaysia is on prevalence. This study aims to investigate factors associated with smoking initiation and cessation which is imperative in designing intervention programs.</p> <p>Methods</p> <p>Data were collected from 11,697 adults by trained recording clerks on sociodemographic characteristics, practice of other risk habit and details of smoking such as type, duration and frequency. Smoking commencement and cessation were analyzed using the Kaplan-Meier estimates and log-rank tests. Univariate and multivariate Cox proportional hazard regression models were used to calculate the hazard rate ratios.</p> <p>Results</p> <p>Males had a much higher prevalence of the habit (61.7%) as compared to females (5.8%). Cessation was found to be most common among the Chinese and those regularly consuming alcoholic beverages. Kaplan-Meier plot shows that although males are more likely to start smoking, females are found to be less likely to stop. History of betel quid chewing and alcohol consumption significantly increase the likelihood of commencement (p < 0.0001), while cessation was least likely among Indians, current quid chewers and kretek users (p < 0.01).</p> <p>Conclusions</p> <p>Gender, ethnicity, history of quid chewing and alcohol consumption have been found to be important factors in smoking commencement; while ethnicity, betel quid chewing and type of tobacco smoked influences cessation.</p

Bio-composting oil palm waste for improvement of soil fertility

Sources of bio-compost as agro-industrial wastes includes wide range of oil palm wastes viz. waste, biomass, palm kernels, empty fruit bunch, mill effluent, trunk and frond compost. Various composting processes are summarized in brief with distinct reference of oil–palm composting covering aerated static pile, and co-composting with earthworms (vermicomposting). However, in-vessel composting and windrow composting has meritorious advantages in composting. This review article refers to various significant roles played by microorganisms associated. Noteworthy study of bio-compost applications and procedures are correspondingly glosses framework of ecological, economical and agro-ecosystemic benefits