Drying and gas or vapor contact with solids – Process – Gas or vapor contact with treated material
Patent
1996-05-24
1998-04-07
Bennett, Henry A.
Drying and gas or vapor contact with solids
Process
Gas or vapor contact with treated material
34552, 422295, F26B 300
Patent
active
057350612
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
This invention relates to apparatus and processes for sterilizing products using saturated steam, followed by the drying thereof. The invention is particularly concerned with ensuring that the products are cost effectively and efficiently dried without the possibility of recontamination during the drying stage.
DESCRIPTION OF PRIOR ART
Conventionally, products are sterilized and dried in an autoclave by a process which basically comprises subjecting the products to saturated steam at elevated pressure followed by the application of a vacuum to remove the water. The vacuum is applied in a single step while heating, after which the autoclave is vented to the atmosphere.
A typical problem with such a system is the potential for recontamination of the sterilized products should the autoclave leak for any reason as in that case air-borne microorganisms can be readily introduced into the autoclave by virtue of the below atmospheric pressure existing therein. Another disadvantage is the necessity to employ relatively expensive vacuum pumps to produce the required pressure reductions for effective vacuum drying. Such vacuum pumps also add considerably to the total time required to sterilize and dry a product.
One proposal to overcome the former of these problems is to reduce the degree of vacuum whilst streaming filtered, preferably heated, air through the autoclave. This, however, considerably reduces the drying effectiveness by further increasing the time required to achieve a suitable degree of drying. It also does not address the problems associated with vacuum pumps.
OBJECT OF THE INVENTION
It is therefore an object of the present invention to provide an apparatus and process which obviates or at least minimises these problems and which provides the public with a useful alternative.
SUMMARY OF THE INVENTION
According to one aspect of the present invention there is provided an apparatus for sterilizing and drying products, said apparatus comprising: order to effect the sterilization of products placed therein, products placed therein, said gas being essentially dry and completely contaminant free, pressurized gas, and contained in the chamber, and the subsequential cycling of gas under pressure into and out of the chamber, is effectively regulated.
The apparatus is particularly adapted for small scale use such as the sterilization and drying of instruments in doctors and dentists surgeries. However, it will be readily appreciated by the skilled addressee that the apparatus can be scaled up to large scale industrial use within the parameters of the defined inventive concept. Such large scale use is exemplified by the sterilization and drying of grain products on a continuous throughput system.
Automation and control of the apparatus can likewise be effected by the application of common general knowledge and the use of appropriately adapted hardware incorporating microprocessors and the like, and specially configured software packages. None of these criteria impinge upon the broad inventive considerations made by the inventor and disclosed herein.
DETAILED DESCRIPTION OF THE INVENTION
The means for supplying gas under pressure to the chamber for drying products placed therein will normally be a compressor however supply may alternatively be made from a gas cylinder or gas generation apparatus. Generally, the pressure of the gas will be in the range of 1 to 100 kPa, most preferably around 80 kPa. Higher pressures are preferred as these reduce the number of cycles required to dry the product. This may be particularly important for porous products. Suitably, in each pressurizing and release cycle, the pressure is maintained for a sufficient period to at least partially equilibrate before being released to atmospheric pressure.
Preferably, the gas pressurizing process is effected in short bursts of between about ten and sixty seconds, and the pressure release is fast and continues until the chamber is substantially depressurized. The drying cycles can continue for periods of
REFERENCES:
patent: 3481692 (1969-12-01), Linder
patent: 3661505 (1972-05-01), Frolich
patent: 3721527 (1973-03-01), Lodige et al.
patent: 3904361 (1975-09-01), Egger
patent: 4239730 (1980-12-01), Fahlvik et al.
patent: 4622800 (1986-11-01), Turtschan
patent: 4637916 (1987-01-01), Henebert et al.
patent: 5196165 (1993-03-01), Harrell et al.
Bennett Henry A.
Electrical Control Systems Pty. Ltd.
O'Connor Pamela A.
LandOfFree
Autoclaving process and apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Autoclaving process and apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Autoclaving process and apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3823