No abstract

Developments in vacuum storage technology present an opportunity to achieve significant improvements on protection, preservation and storage of agricultural commodities for residential and commercial use. Sub-baric storage is a environmental friendly, non-residue organic technology which provides chemical-free and insect contamination-free products. Due to creation of vacuum, there is a change in the environment inside the storage structure. This study therefore contributes an important knowledge and method in the development, fabrication and application of a sub baric storage bin (SBSB) as a best alternative to the commonly used traditional and modern storage structure. In its embodiment, the work focuses on the design and fabrication of the sub-baric storage bin to provide efficient storage of food grains by preventing the use of pesticides and insecticides and to reduce material loss during storage, a sub-baric storage bin of 500 kg capacity was designed and developed. The developed storage bin consists of storage chamber (500 kg), Vacuum pump, suction blower, grain inlet with pipe for loading, grain outlet for unloading, vacuum gauge, thermocouple, control panel, agitator, air filter, two inlet valves for gas infusion, vacuum release valve and SS mobile skid. The designed sub-baric storage bin is cylindrical in geometry with conical shape at bottom side and flat circular plate on top side and the storage bin has capacity of 500 kg to store food grains with hopper angle of 60°. The storage bin was designed in such a way that, it has provision for both bulk and bag storage and to work from 0-650 mm Hg vacuum. The developed SBSB was subjected to hydraulic pressure test and vacuum drop test to ensure a safe operation. It was observed that there was no implosion (compression) or explosion confirming to the fact that the design was adequate and also safe to operate. Also, there were no signs of bulging, buckling or any deformations observed in any of the components or the pipe lines, connections, fixtures or fasteners. Hence, it was concluded that the designed equipment could be operated safely at 650 mm Hg vacuum pressure satisfying all the applicable safety assurances and standards relevant to the industry.