EP0376906A1

EP0376906A1 - A method and an apparatus for reclaiming a false ceiling made of panels where mineral synthetic fibres are present

Info

Publication number: EP0376906A1
Application number: EP89830570A
Authority: EP
Inventors: Stefano Sangiorgio
Original assignee: MULTITEC Srl
Current assignee: MULTITEC Srl
Priority date: 1988-12-29
Filing date: 1989-12-22
Publication date: 1990-07-04
Anticipated expiration: 2009-12-22
Also published as: DE68903487D1; EP0376906B1; DE68903487T2; ATE82352T1; JPH03197770A; IT1227288B; IT8848731A0

Abstract

This method comprises a first step where a suitable coater is sprayed by means of a suitable nozzle (18) on the exposed lower surface of a false ceiling (24), which coater forms a thin protective film. In a next step the same coater is sprayed on the upper surface of the insulating mat, which is spread on top of the false ceiling staves (22), by using a nozzle (18) which is provided with a double wedge fairing (20) which fits into the interstices between the same staves (22).

After such two steps, the metal staves (22) and the mats, which are made of synthetic mineral fibres therein contained, are covered on both sides by a protecting film which prevents possible contaminations by fibres during the next removal by skillful workers.

Description

The object of the present invention is a method for reclaiming the false ceilings provided with coating or with insulating mats made of mineral synthetic fibres together with the apparatus which is used for said purpose.
Recently, the risks of contamination by fibrous substances mainly originated by inhalation of elongated fibrous substances such as asbestos, glass fibres and the like have been clearly shown and explained also to the public opinion. While for the asbestos a special law has been divulged which imposes the removal thereof, the same did not happen so far for mineral synthetic fibres which, up to now, have been widely used as thermic and/or sound insulating materials and which in the light of the latest knowledge appear to be a potential danger.
The purpose of this invention is to remove the layer of fibrous material, specifically from staves made false ceilings, by which the possibility of contamination is greater, in a simple and saving way, while ensuring the maximum safety to the skilled workers both when working on the place and during the transportation to the discharge.
The method of reclaiming from mineral synthetic fibres herein described is remarkably different from the conventional method adopted for reclaiming from asbestos: in fact, contrary from the latter, sealed yards are not provided and as a consequence big air extractors provided with absolute filters are not required.
This reclaiming method at equal safety levels, compared with the conventional method, offers three main advantages:
- The treatment of this invention can be applied to premises which must not necessarily be cleared of furniture.
- The treatment of this invention can be made very speedily.
- The treatment costs are very low.
All these operation advantages depend on the invention idea which is at the base of the method: all the contaminating material is handled in safety conditions, after being covered with a thin protecting film. Thus the only source of pollution which originates from this type of reclaiming, that is the release of fibres due to mechanical action, is suppressed at the origin.
Specifically, according to the invention, the method provides the following steps:

1. All the furniture, the household goods, the aerators and any other object in the rooms to be reclaimed is sealed by means of strong plastic sheets and of adhesive wide tape; the passageways towards other rooms are shut by plastic sheets and by adhesive tape of the same type.
2. Without removing the metal staves of the false ceiling a suitable coat is sprayed on the lower surface by means of a pressurized air nozzle which forms, in a short time, a thin film over all the treated surface.
3. Similarly, by means of a suitable spearlike T nozzle which is provided with a fairing in the shape of a double wedge whereby its penetration is made easier, the upper suface of the false ceiling is covered by inserting the spearlike nozzle into the interstices which exists between each pair of staves and by spraying from above the encapsulating matter.
After these two operations the metal staves and the mats made of mineral synthetic fibres therein contained are covered by a protective film over both the sides thereof.
4. They are then removed and collected into sealed containers and conveyed to the discharge.
5. The plastic sheets are folded with care and the premises are cleaned in a wet way.

The description of the method and apparatus employed will be better followed by referring to the annexed drawing tables wherein:

- Fig. 1 shows a truck on which the apparatus is mounted for spraying the coating;
- Fig. 2 and 3 show the front and the side of the T nozzle.
- Fig. 4 shows the same nozzle while it sprays the coating liquid on the upper surface of the false ceiling.

With reference to the figures the employed apparatus for generating the aerosol or nebulizing jet comprises a silenced compressor 4 adapted for producing about 8 atm and a pressurized reservoir 6. All the above is assembled on a truck 8 with a series of safety valves and pressure gauges not shown in the figures, whereby the use and checking of everything on the truck is ensured; for the movement of the fluids from the reservoir to the nozzle 10 rubber spiral hoses 12 are used.
On spearlike nozzle 10, provided with a handle opening 14, a single nozzle 16 can be inserted which produces a fan spray to be used in the second step of the process or a T nozzle 18 which produces a fan double jet directed towards opposed parts and which is used in the third step. The last nozzle 18 is provided with a double wedge fairing 20 which makes it easier to insert one of them between two metal staves 22 and to withdraw it therefrom; the two wedges are opposed to one another and are as long as the two segments of the nozzle.
The encapsulating matter is a one-component viscous fluid (vinyl derivative) which is diluted by water. in the effected tests a product was used which is sold under the trade name of FIRECHECK; it can be sprayed or brush-applied and, when water is vaporized, it forms an elastic membrane, adhering and sturdy, chemically resistant and which can stand structure expansion up to eight times its linear dimension without tearing.
The product is not toxic and is scentless when dry; furthermore it is a good flame retardant and can be used within a temperature interval from - 50 to + 90 degrees centigrade.
The premises, which are the object of reclaim action, and the passageways of which are normally closed, are further screened by the use of resistant poly-ethylene sheets which are applied by means of a wide adhesive tape over all the doors which are outside of the working area; other polyethylene sheets, of which the width is not less than 50 cm, are placed on all the walls along the perimeter of the false ceiling. The aerators and the glass ceiling bowls of the rooms are also sealed so that at the end of these operations the only surfaces which are exposed to a possible contamination by fibres, although little probable, during the subsequent steps of the work, are the floors.
After such a preparation of the working area, the skillful workers actuate the next reclaiming steps. The filmlike coating is applied by means of the spearlike nozzle 10 of which the opening is controlled by a handle 14 which sprays the encapsulating matter through nozzle 16. The propulsion of the aerosol jet is generated by compressed air within a spraying time of 3-5 seconds.
In practice the spearlike nozzle is kept at about 20-30 cm from the surface to be treated while the lower surface of the false ceiling is totally covered.
After water evaporation, a film is formed which thickness is included between 0,2 and 0,4 mm and perfectly adheres to the metal staves surface which is not regular.
At this moment the next step is started which comprises coating the upper side of the false ceiling which faces the proper ceiling by means of the encapsulating product.
This is accomplished by replacing nozzle 16 of spearlike 10 with T nozzle 18 which is provided with a particular fairing in the form of a double wedge as above in order to make it easy to insert it between two staves 22; the propulsion is always provided by the compressed air which is supplied by the compressor.
The spearlike faired nozzle is penetrated into the slits which usually exist between each pair of staves and when suitably handled without removing the staves, aereosolizes the encapsulating product within the area included between the roof of the room and the false ceiling whereby all the surfaces of the false ceiling are covered especially the mat surfaces with a filmy layer. In the effected tests it was proved that the double jet generated by the T nozzle effectively covers a distance of about 160 cm, so that, by means of a simple rotation a false ceiling surface of nearly 2 mq can be covered.
In addition, when the possibility is added of sliding the nozzle along the slit between two staves, the whole upper surface of the false ceiling can be covered by means of a limited number of insertions of the same spearlike nozzle.
Actually, the nozzle is inserted about every 70-90 cm and for such a depth that the nozzles reach a position higher than the surface of the mats 24 of mineral synthetic fibres. The jet is then actuated and the nozzle is moved while regularly rotating it without shocks.
This operation is repeated at the number of places which are the minimum required for ensuring the encapsulation of all the surface.
At the end of this step also the upper surface of the false ceiling is covered by the encapsulating matter and after a time interval of 1-2 hours which allows the water to evaporate, the false ceiling can be removed.
For this operation the metal staves, together with the mats are removed with the utmost care and while keeping them horizontal they are introduced into mobile and sealable plastic containers.
After unhanging the false ceiling and confining the resultant material, in addition to the polyethylene sheets used for sealing the rooms, the wastes are led away and are sent to the discharge and subsequently the wet cleaning of the rooms is carried on according to the usual procedures before giving back the reclaimed premises.

Claims

1. A method for reclaiming false ceilings made of staves and provided with mats or linings of mineral synthetic fibres characterized by the fact of comprising the following steps:
passage ways, air intakes, windows of the premise to be reclaimed are sealed with plastic sheets and adhesive tape;
the lower surface of the stave false ceiling is sprayed by means of a compressed air nozzle, a suitable coating adapted for forming in a short time a thin film over all the treated surface;
the upper surface of the false ceiling is similarly covered by inserting the spearlike compressed air nozzle into the interstices which exist between each pair of staves and spraying the encapsulating material from above;
whereby all the metal staves along with the mineral synthetic fibres therein contained are covered by a protecting film over both sides before then removing them which thing can happen without any danger that any fibres be released.

2. A method for reclaiming as claimed in claim 1 wherein the encapsulating/covering product is a water diluted vinyl derivative.

3. Apparatus for reclaiming false ceilings made of staves provided with mats and/or clad with mineral synthetic fibres according to the method of the preceiding claims characterized by the fact of comprising:
- a presurized container of the liquid to be sprayed, said container being combined with an air compressor for generating an aerosol jet;
- a nozzle with a handle opening and mounted at the end of a flexible tube for directing the jet during the work and on which the following can be alternately mounted;
- a single nozzle for producing a spray fan over the lower surface of the staves during the step of covering the lower surface of the false ceiling; and
- T nozzle adapted for producing a fan jet in opposed direction during the step of covering the upper surface of the false ceiling; said nozzle being provided to said purpose with a fairing with double wedge which makes it easier the insertion and the withdrawal into and out of the interstice between each pair of staves.

4. A method and apparatus for reclaiming false ceilings made of staves which are clad and/or covered with layers of mineral synthetic fibres substantially as described in the specification and illustrated in the attached drawings.