Drying and gas or vapor contact with solids – Apparatus – With means to treat gas or vapor
Patent
1981-09-28
1983-08-23
Schwartz, Larry I.
Drying and gas or vapor contact with solids
Apparatus
With means to treat gas or vapor
34 57A, 34242, 432242, F26B 308
Patent
active
043996183
DESCRIPTION:
BRIEF SUMMARY
This invention relates to a method of sealing at a fluidized bed and to a device for carrying out the method. The sealing refers primarily to openings between zones or sections in the bed or between the bed and its surrounding.
A fluidized bed consists in principle of a container, which partially is filled with solid small particles, of which by injection of gas, usually through the container bottom, the major part is maintained suspended, in such a manner, that the suspended particles and the gas together constitute a system, which owns many properties of a fluid. In order to bring about and maintain fluidization, of course, certain conditions must be met.
It was found that a very good and uniform heat transfer can be achieved between the bed, i.e. the suspended particles and the gas, and objects occurring in the bed and having a temperature different from that of the bed. Therefore, fluidized beds are utilized a.o. (abbreviation for among other things) for the heat treatment of, for example, large workpieces of steel, which require efficiently controlled and uniform heating and cooling in order a.o. not to get distorted.
Fluidized beds also can be used as "cooling beds" for the cooling of cast or hot-worked, for example hot-rolled products in connection, for example, with steel manufacture. Fluidized beds offer in this respect a number of advantages, such as reduced bed size and improved environment in connection with the bed, compared with cooling beds using free or forced air cooling as in conventional cooling beds.
For controlling the cooling, it may be expedient in many cases to divide the bed into several zones or sections, through which the workpieces to be cooled in the bed are to pass.
One problem in connection therewith, of course, is to effect sealing between the zones. The workpieces namely are to be transported between the zones, i.e. are to be transferred from a certain zone to an adjacent zone after having stayed for a certain period in the firstmentioned zone, and for this reason there must be openings between the zones. A corresponding problem prevails in connection with the introduction of workpieces into the bed and their removal out of the same. Transfer of bed material between the zones can be tolerated only to a small degree, because otherwise the possibility of adjusting and controlling would be poor. Bed material must not leak out from the bed, either, when the workpieces are being fed in and discharged, because such leakage would yield a.o. an unsatisfactory environment about the bed and increase operation costs.
It was found to be very difficult, at the infeed and discharge to effect sealing between the zones by applying conventional technique. The difficulty is due to several factors, a.o. high temperature as well as clogging and wear caused by the bed material. The cooling bed has to meet very high requirements on reliable operation, because the bed mostly must be capable of receiving workpieces at the rate and time at which the workpieces are delivered from other equipment, for example a rolling mill in which they have been worked.
The present invention relates to a method and a device for sealing, at which the bed material is utilized, and the sealing is not stationary, but is built up partially during operation.
The invention, thus, relates to a method of sealing an opening between two zones in a fluidized bed and/or between the bed and its surrounding, in which bed particles are intended to be maintained suspended by means of a carrier gas, which is introduced into the bed bottom beneath the level of the opening, through which primarily workpieces to be treated in the bed are intended to pass, and which opening, for example, is a horizontal gap in a vertical partition wall between the zones or between the bed and its surrounding.
The method is characterized in that a heap or several heaps of particles, by utilizing the movements of the particles and carrier gas in the bed, are caused to build up at the opening to such a height, that each opening is covered or substantially
REFERENCES:
patent: 3492740 (1970-02-01), Geipel et al.
LandOfFree
Method of sealing a fluidized bed and device for carrying out th does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of sealing a fluidized bed and device for carrying out th, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of sealing a fluidized bed and device for carrying out th will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1943378