PVK Mini Dal mill machine is conservative in size, low power consuming, and furthermore, relatively less price from others. It likewise comprises evaluating instruments for the reviewing of Dal. This machine offers dust-free activity, doesn’t cause contamination, and holds proteins.
The mill consists of four units viz., splitting unit, sieve, aspirator and polisher. The premilling treatment is given by soaking difficult to mill pulses grains in sodium bicarbonate solution. The splitting unit is comprised of two emery discs run 1.0 hp, single phase electric motor. One of the discs is fixed and another is revolving type. The clearance between them is adjusted by screw mechanism operated by hand wheel. The capacity of this unit is 40-45 kg per hour for pigeonpea and around 60 kg per hour for mungbean and urdbean. The sieve unit consists of two reciprocating type of easily removable. Different sizes of sieves are required for various grain sizes. It separates mixture in three different parts coming out from individual outlets, lower one is for broken, middle for dal and upper are retains the mixture of husked and dehusked grains. The aspiration unit consists of two blowers (aspirators) and a cyclone separator.
One of the aspirator positioned near the outlet of splitting unit separates only husk and powder from the milled mixture and provides dust free operation. The second aspirator separates husk from dal moving from the polisher unit. Both the aspirators are connected to a cyclone separator, which collects powder from the mixture of husk and powder so as to avoid its spreading in the atmosphere. In polisher, polishing is done with the help of two screw conveyors wrapped with leather and enclosed in a casing. The friction of dal between leather and inner surface of casing enables to polish it and removes the husk, which still adheres to dal.
It is necessary to give pre-treatment to pigeonpea grains before milling. Grains are soaked in 6% solution of Sodium bi-carbonate for 40 minutes and dried. The grains of mungbean and urdbean do not require any premilling treatment. In case of pigeonpea, the maximum efficiency over 72% can be obtained. This machine is recommended to be use at cottage industries level.