The palm farmers of Bangladesh are suffering for want of an extraction machine. Therefore, a research was undertaken to design and develop a manually operated palm oil extraction machine at the department of Farm Power and Machinery, Bangladesh Agricultural University. It is a press type machine. A screw leads a piston manually in a perforated cylinder to press the mesocarp (pulp of palm fruit) to extract oil. The volume of the cylinder of the machine was found 0.03 m3 and maximum 20 kg fruits can be accommodated at a time. The amount of crude palm oil press at full capacity of the machine was found 8 kg/hr., which is higher than any manually operated extracting machine available in the market. The crude oil extraction efficiency of the machine without palm kernel was also found satisfactory. Application force on screw can be increased by increasing the length of the handle and number of persons according to filling condition of the cylinder. The machine was developed with locally available materials for having low purchase price and smooth repair and maintenance. So that, it will be easily affordable to the palm farmers of Bangladesh. The developed machine will solve the burning need of palm farmers in Bangladesh.
One of important sources of biomass-based fuel is Jatropha curcas L. Great attention is paid to the biofuel produced from the oil refinery extracted from the Jatropha curcas L. seeds. A mechanised extraction is the most efficient and feasible method for oil extraction for small-scale farmers but there is a need to extract oil in more efficient manner which would increase the labour productivity, decrease production costs, and increase benefits of small-scale farmers. On the other hand innovators should be aware that further machines development is possible only when applying the systematic approach and design methodology in all stages of engineering design. Systematic approach in this case means that designers and development engineers rigorously apply scientific knowledge, integrate different constraints and user priorities, carefully plan product and activities, and systematically solve technical problems. This paper therefore deals with the complex approach to design specification determining that can bring new innovative concepts to design of mechanical machines for oil extraction. The presented case study as the main part of the paper is focused on new concept of screw of machine mechanically extracting oil from Jatropha curcas L. seeds.
Basic functions of the oil dewaxing machine consist in separating the solid component (structures) and liquid component (oil). Linear or nonlinear pressing (vertical, horizontal, or angled) by a sliding piston or rotary screw is frequently used for small-scale production. As the technological set-up for Jatropha processing is not yet fully developed and progress may be made in terms of mechanisation  we present mentioned complex approach in the following case study focused on conceptual design of screw extractor press extracting biooil from Jatropha curcas L. seeds for small-scale production. First, the research team analysed sources [7–9, 13–17, 19] and information obtained during interview realized in Sumatra and Java (Indonesia)—Figure 2. Low production cost , high productivity , and higher oil yield  were considered as essential extracting machines user’s needs (Table 1).