CN2352909Y

CN2352909Y - Freezing type drying machine

Info

Publication number: CN2352909Y
Application number: CN 98219751
Authority: CN
Inventors: 张祯儒
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-08-28
Filing date: 1998-08-28
Publication date: 1999-12-08
Anticipated expiration: 2008-08-28

Abstract

The utility model belongs to a drying apparatus. The utility model is characterized in that a vacuum leakage valve in the exiting structure of a freeze drier is cancelled. A delayer is connected with a vacuum pump and a pump trap valve. As a standard leakage valve is cancelled, dangers for discarding products because of the failure of the leakage valve can be thoroughly eliminated, so that the utility model fundamentally puts an end to hidden troubles for causing great losses. By making use of a cold trap of the drying apparatus as a low temperature pump, optimum pressure is formed in the sublimation process of the product. Time of the delayer is set according to the characteristics of a freeze drying product and the requirements of vacuum pressure. Therefore, the utility model does not need to add air on the outside of the freeze drier to regulate the pressure of a drying box, which not only reduces the load of the freeze drier, but also shortens the freeze drying period of the product.

Description

A kind of freeze drier

The utility model belongs to a kind of drying equipment.

Freeze drier generally all is that hydrous matter is frozen into solid earlier, under the condition of vacuum, heat, make ice in the material sublime up into cold-trap and condense into frost, drying and dehydrating at low temperatures, the material residual moisture is lower than below 3% even 1%, make material preserve its original proterties and function, its constancy of volume.Owing to do back material lack of water and anoxic,, make its proterties and function constant admittedly make material be able to long preservation.Existing freeze drier adds the standard seepage valve of an adjustable pressure at the drying box top, put into filtrated air and make it to reach the drying pressure of the best to shorten the omnidistance time of freeze-drying to drying box.But there is following problem in this structure:

1, standard seepage valve exists problem malfunctioning in the use.If standard seepage valve because a variety of causes is malfunctioning, will suck the machine room air that bacterium is arranged, cause that contamination of products scraps, perhaps add the air superpressure, also will cause the danger of product rejection.

2, the air of putting into drying box by the seepage valve contains certain moisture content and heat, has increased the load of freeze dryer, produces contradiction with energy-conservation going up.

3, vavuum pump begins to finish and will ceaselessly turn round until freeze-drying from freeze-drying prods, has increased the consumption of the wearing and tearing of vavuum pump and oil plant etc.

The purpose of this utility model provides a kind of freeze drier, and it does not need to add the pressure that air is regulated drying box outside the freeze drier system.

The utility model is achieved in that this freeze drier, it is by drying box, cold-trap, freezing unit, vavuum pump, heat medium circulation pump, heater, formations such as heat exchanger, the shelf in the drying box links to each other with heat medium circulation pump, and heat medium circulation pump links to each other with heater, heater links to each other with heat exchanger, heat exchanger links to each other with the shelf of drier again, and heat exchanger links to each other with freezing unit, and the drying box inner space links to each other with the cold-trap inner space by case trap valve, cold-trap links to each other with freezing unit, vavuum pump links to each other with cold-trap by pump trap valve, and cancellation vacuum seepage valve has a delayer to link to each other with pump trap valve with vavuum pump.

Owing to cancelled standard seepage valve, thoroughly eliminated because of the malfunctioning danger that makes product rejection of this valve, fundamentally stopped to cause the hidden danger of heavy losses.And utilize the equipment cold-trap as cryogenic pump, form optimum pressure in the product sublimation process, according to the characteristic of freeze-drying prods and the requirement of vacuum pressure, configure the time of delayer, when drying box need boost, the delayer that configures cuts out vavuum pump and pump trap valve, like this, because the inside of drying box becomes sealed shape with the space that the cold-trap that is attached thereto constitutes, at this moment, in the continuous operation process of cold-trap, need ice in the product of freeze-drying in continuous sublimation process, discharge the not concretive gas (as oxygen etc.) of a large amount of water vapours and trace, water vapour constantly condenses, and the not concretive gas in this space progressively increases, cause the increased pressure of gas in the drying box, to improve freeze-drying efficient.When the increased pressure of drying box arrived specified pressure, delayer was opened vavuum pump and pump trap valve, to reduce the pressure of gas in the drying box.The utility model no longer needs to add the pressure that freeze drier air is in addition regulated drying box, and the load of freeze dryer is reduced, and the product lyophilization cycle is shortened.

Below in conjunction with embodiment and accompanying drawing the utility model is further described.

Fig. 1 is the utility model one example structure schematic diagram.

Drying box 1, cold-trap 2, the freezing unit 3-1 that links to each other with heat exchanger, the freezing unit 3-2 that links to each other with cold-trap, vavuum pump 4, heat medium circulation pump 5, heater 6, heat exchanger 7, magnetic valve 8, case trap valve 9-1, pump trap valve 9-2, the vent valve 9-3 that links to each other with drying box, the vent valve 9-4 that links to each other with cold-trap, delayer 10.

In the present embodiment, drying box 1 and cold-trap 2 are connected with independently freezing unit 3-1,3-2 respectively.Put into when the product of wanting freeze-drying on the shelf of drying box 1, open freezing unit 3-1, cool to assigned temperature, product is frozen into solid by the characteristic of product.Under the effect of freezing unit 3-2, cold-trap 2 temperature are reduced to below-40 ℃, open vavuum pump 4 then, open pump trap valve 9-2, take out 3 to 5 minutes after, open case trap valve 9-1, make vacuum pressure be lower than 13.3Pa, just can heat.Open heat medium circulation pump 5, heater 6, the freeze-drying curve of pressing product heats drying box 1 shelf.Because being heated, the product that freezes quickened the process of distillation, the a large amount of steam that distil out are condensed into frost by cold-trap 2, and vavuum pump 4 is if remain in operation, because the hypotony of system, freeze drying rate is slowed down, so just have a mind to increase system vacuum pressure to keep best literization speed.Now adopt delayer, close vavuum pump 4 and pump trap valve 9-2 on request, progressively increase system pressure with a part of noncondensable gas that produces in the freeze-drying prods sublimation process, when surpassing rated pressure, vacuum meter makes delayer 10 open vavuum pump earlier after 4 some seconds, open pump trap valve 9-2 again, so just make freezing whole-process automatic being under the optimum pressure of doing, finish until whole moisture content lyophilizations of product.

Claims

1, a kind of freeze drier, it is by drying box (1), cold-trap (2), freezing unit (3), vavuum pump (4), heat medium circulation pump (5), heater (6), heat exchanger formations such as (7), shelf in the drying box (1) links to each other with heat medium circulation pump (5), and heat medium circulation pump (5) links to each other with heater (6), and heater (6) links to each other with heat exchanger (7), heat exchanger (7) links to each other with the shelf of drier (1) again, heat exchanger (7) links to each other with freezing unit (3), and drying box (1) inner space links to each other with cold-trap (2) inner space by case trap valve (9-1), and cold-trap (2) links to each other with freezing unit (3), vavuum pump (4) links to each other with cold-trap (2) by pump trap valve (9-2), it is characterized in that having a delayer (10) to link to each other with pump trap valve (9-2) with vavuum pump (4).