FDG series vacuum cryogenic drying equipment is a new generation of food-processing equipment developed by our company on the basis of absorption of foreign advanced technology and combination with advantages of the domestic product in the parallel industry and is our new contribution to food-processing industry. In November 2002, the company firstly developed the cryogenic drying equipment with 280m2 drying surface area of single machine in China, which filled the gap in large-sized vacuum cryogenic drying equipment in China. At present, the company can manufacture series of such equipment with drying surface area of single machine from 0.5m2 ~280m2. Its customers are distributed in Zhejiang, Henan, Yunnan, Shandong, Fujian, Hainan, Hubei and other provinces. The machines nationwide are in good service and the quality of the freeze-dried food produced by this equipment fully complies with for the export standard.
FDG series vacuum cryogenic drying equipment mainly includes food pre-freezing system, drying bin system, heating system, vacuum system, refrigerating system, material conveying system, medium system, pneumatic system, cleaning and sterilizing system.

※ The vacuum system is in combination structure of water-sealed pump + oil-sealed pump. The extraction of pre-vacuum is performed by oil-sealed pump group of large power and the vacuum for operation remains by water-sealed Roots pump group of small power so as to reduce energy consumption. Meanwhile, the water-sealed pump group can remove vacuity instability of the system due to poor water-removal performance of oil-sealed pump and emulsification deterioration of the pump oil.
※ Heating is conducted in closed water circulation system, where three-way adjusting valve is used for automatic adjustment of heat supply to the water circulation system to precisely control temperature of the heating plate. Besides, nitrogen is used for automatic pressure-keeping to ensure the working temperature of the hot water reaching 120℃.
※ The rear-installed and side-installed water-catching cold trap is adopted. Compared with the outside-installed cold trap, the former one has advantages of short canal, lower resistance, and smooth steam canal, uniform and high-efficient water-catching. The cold trap uses special method of ammonium single-phase circulating refrigeration. It is more stable in supplying refrigerating liquid and easier in operation than the general method of liquid supply.