Powder and granular material supply system for closed system

A granular material supply system for a closed system, for supplying a granular material to a granular material using apparatus without opening the closed system to an external environment, said granular material supply system comprising:

• a granular material supply unit holding a granular material;
• a granular material feed unit that receives the granular material from the granular material supply unit and feeds the granular material, wherein the granular material feed unit includes:
• a pressure case provided with an inlet connected to the granular material supply unit and an outlet for feeding the granular material, and
• a conveying means disposed in the pressure case to convey the granular material received through the inlet to the outlet;
• a weighing means for weighing the granular material being conveyed by the conveying means is disposed in the pressure case;
• the conveying means includes a belt conveyor having a plurality of carrier rollers and a conveyor belt supported on the carrier rollers;
• the granular material supplied onto the belt conveyor through the inlet is conveyed by the belt conveyor;
• and
• the weighing means weighs the granular material on a part of the conveyor belt between the two adjacent carrier rollers installed at positions other than those directly below the inlet.