Onion Cold Store

Onions should not be stored unless adequately cured(dried) either in the field or by artificial means. It is necessary to dry the neck tissues and outer scales until they rustle when handled, otherwise, the bulbs will rot in storage. They can be artificially cured by blowing heated air at 110-115F (43-46C) through mesh bags for 8-12 hours or longer.

Onions are held in 60 lb. sacks, slatted crates, and pallet boxes holding about tons of loose onions, in bins, or in large bulk storage. When in sacks, these should be loaded cross-wise or "air-stacked" 5-6 high. The stacks should be set on floor racks. Individual stacks should be separated a few inches to allow free air circulation. Sufficient Airflow of product is adequate. When in crates or pallet boxes, they can be stored one on top of the other to make full use of the storage space. Onions should be held at 32F (0C) for maximum quality and shelf life. Storage at ambient temperature may be acceptable for short periods (1-1.5 months) depending on the variety.

Basis of design for Onion cold Storage-350MT

Proposed Cold storage size: 17.11mtr. x 16.028mtr. x 5.48mtr(H)Ext.dim

Product to be stored: Dry Onion (Red or white)

Storage capacity : 350 MT x 4 nos. = 1400 MT

Storage period: 06 months

Incoming load temp. : 350C

Incoming Quantity: 50 MT/day

Room temperature required : 0 to +2 Deg.C

Relative humidity: Below 70%

Insulation: 100mm PUF panel

Pull downtime : +35 to 0 Deg. C within 96 Hours for 50 ton

Ambient temperature : 45 Deg.c

Air ventilation: Suitable Ventilation rate for each cubic meter will be maintained. Adequate CO2 levels should be maintained

Inside room air circulation: Heavy-duty fans will be provided 4 NOS. PER ROOM x 4 ROOMS = 16 FANS

Evaporating unit: Total 03 evaporator units in a room with Al. Fins, having ref. the capacity of 20 kW x 3 no.

Ducting: Perforated MS duct fabrication 04 nos/room for recirculating air outlet

Condensing unit: Air-cooled condensing unit of 20 kW x 3 nos.

Compressor: Scroll /Semi-hermetic of Copeland / Bitzer /Bock or any equivalent make.

Refrigerant : R-404a

Electrical supply : 415V / 3 phase/ 50 Hz