Device for separating two zones with different environment

Details Device for separating two zones with different environment Device for separating two zones with different environment

1999-10-19

2000-11-14

Joyce, Harold

Ventilation

Having protecting air current

454190, F24F 900

Patent

active

061462675

DESCRIPTION:

BRIEF SUMMARY
The present invention relates to a device for separating first and second zones in which different environments prevail.
The term "environment" as used here means the air conditions, gas and particulate concentrations and, in particular, the contaminants' concentrations, pressure and temperature conditions, hygrometry, etc.
The invention finds a particularly advantageous application in the industrial spheres of agro-foodstuffs, medicine, biotechnology, electronics, the nuclear industry and the chemical industry, in which spheres it is necessary to maintain different environments in zones which communicate with each other, while at the same time allowing the frequent passage of objects or products from one zone to another.
In the agro-foodstuff or pharmaceutical spheres of industry, or alternatively in a hospital environment, the issue is one of protecting clean zones in which the atmosphere is sterile from external contamination, it being possible for these zones to be at a slightly raised pressure compared with the outside, while at the same time allowing products or objects to pass from the said clean zones to the outside where there is a certain amount of ambient contamination, and vice versa, without transferring the contamination.
By contrast, in the nuclear sphere of industry, the issue is one of protecting the outside from possible contamination from a contaminated zone while at the same time also allowing objects or products to pass from the outside into the contaminated zone, and vice versa. In this instance, it is the contaminated zone which is to be confined with respect to the outside.
There are currently three known types of solution for separating two zones which communicate with each so as, for example, to allow objects in and out: protection by a mechanical airlock, protection by ventilation and projection using a curtain of air.
Protection using a mechanical airlock consists in inserting between two zones that are to be isolated from one another a zone in which the air is controlled, this zone being separated from the said zones by airtight doors which can be actuated to make them open and close.
The main drawback of such a mechanical airlock is that products or objects can be transferred from one zone to the other via the said airlock only at slow rates, because of the opening and closing of the doors to this zone.
When the zone that is to be protected contains a product likely to be contaminated by the ambient air, protection by ventilation consists in injecting, into the zone that is to be protected, a laminar flow which is blown outward through the opening via which this zone is accessed. In the reverse scenario, when the personnel and environment outside a contaminated space need to be protected, dynamic confinement is provided by employing extraction ventilation in this contaminated space. In both instances, an empirically determined formula sets a minimum air speed of the order of 0.5 m/s for the ventilated air in the plane of opening via which the two zones communicate, so as to avoid the transfer of contamination in the protected zone.
The efficacy of this technique of providing protection by ventilation is not, however, perfect, particularly in so-called "break-through" situations, that is to say situations where objects or products are transferred from one zone to another.
Furthermore, this protection solution entails treating and monitoring, as the case may be, the entire zone that is to be protected, whether this be the clean zone or the contaminated zone.
Thus, when the zone that is to be protected is very large, treating and monitoring it lead to a particularly high equipment and running cost.
Finally, this technique of providing protection by ventilation provides protection only in one direction, that is to say that it applies only when transfers of contamination can occur in just one direction.
The technique of providing protection using a curtain of air consists in injecting simultaneously, into the separation zone via which the two zones communicate, one or more adjacent

REFERENCES:
patent: 3143952 (1964-08-01), Simons
patent: 4009647 (1977-03-01), Howorth
patent: 4534277 (1985-08-01), Gilmor
patent: 4700688 (1987-10-01), Seacy et al.
patent: 5306209 (1994-04-01), Lang
patent: 5413529 (1995-05-01), Aragon
patent: 5934992 (1999-08-01), Sohier

Affiliated with

Also associated with

Rating

Device for separating two zones with different environment does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Device for separating two zones with different environment, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for separating two zones with different environment will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2060532