Agitating – Mortar mixer type – Methods
Patent
1994-01-28
1995-09-19
Jenkins, Robert W.
Agitating
Mortar mixer type
Methods
366101, 422133, B28C 506, B01F 1302
Patent
active
054511046
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a method of producing foam in accordance with the precharacterising portion of claim 1. The invention further relates to a foam generator in accordance with the precharacterising portion of claim 1.
Foam was previously produced principally by mechanical mixing. It is known from DE-C-3631221 C1 to form a foam from a foamer and water and to mix successively a hydraulic bonding agent, e.g. cement and a pulverulent mineral material into this foam. When the foam mass is loaded with the bonding agent at the time when the main component is mixed in, namely the pulverulent mineral solid material, there is the danger of void formation. The resulting foam can therefore no longer be simply further processed. It is also known to intimately mix a finished foam with different pulverulent mineral materials and then to put both foam mixtures together and again to mix them mechanically into a foamed building material (EP-A 0299482). Only those materials which have relatively long pot and processing times (>30 seconds) can be foamed with these known mechanical foam producing methods. These include filling foams in mining and slowly setting repair and insulating mortars.
There are also methods for foam production in which the foam is produced by a chemical reaction. These include the production of polyurethane foam in which the foamable medium reacts with water or moisture in the air. Finally, there are also methods of foam production by propellant gas in which propellant gas is initially mixed in liquid form into the medium to be foamed and the foam is produced subsequently by transition of the propellant gas from the liquid into the gaseous phase.
A method and an apparatus of the type referred to above are known from EP-A-0 288 106. In this, foamable cement slurry is deflected within the mixing chamber whilst simultaneously nitrogen is injected into the deflection region. The cement foam is subsequently introduced into bores in the earth. It has been found that this technology needs to be improved, particularly with regard to the processing of different materials.
It is the object of the invention to make a method and a generator for producing foam available which have a previously unachieved range of use whilst including bonding agents with extremely short pot and processing times and may be matched to the different uses with small expense.
In order to solve this object the method in accordance with the invention has the features in the characterising portion of claim 1 whilst the foam generator in accordance with the invention is distinguished by the characterising features of claim 11.
A substantial advantage of the invention by comparison with conventional foam producing methods and apparatus resides in that any gas, thus even air, CO.sub.2, steam or also any other desired gas mixture can be used in the production of foam. The same applies also to the foamable, liquid or pasty medium. The pneumatic production of foam in the mixing chamber takes place continuously and, thanks to the laminar flow and the uniform porosity of the partition wall, so uniformly and rapidly that the finished foam is produced directly after the liquid or pasty foamable component is brought together with the gaseous medium responsible for the foaming. The invention may thus be used also on those foamable media which previously appeared unsuitable for the production of foam due to their short pot and processing times (<30 seconds).
The introduction of the gaseous medium into the mixing chamber through a partition wall traversed by numerous micropores is responsible in an advantageous manner for an optimum distribution of the foam bubbles in the foam. With a uniform size of the micropores in the partition wall a uniform air bubble or pore size in the finished foam is also ensured. This uniform air pore size may be preset in accordance with a further embodiment of the invention by a suitable choice of the micropores in the porous partition wall, which is preferably of tube or pipe shape. In an advantageous embodiment
REFERENCES:
patent: 2615693 (1952-10-01), Matirko
patent: 4674888 (1987-06-01), Carlson
patent: 5035842 (1991-07-01), Mohn
patent: 5055272 (1991-10-01), Wheeler
Kleen Eugen
Muller Claus-Michael
CRC-Chemical Research Company Ltd.
Jenkins Robert W.
LandOfFree
Method and apparatus for producing foam 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 and apparatus for producing foam, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for producing foam will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1824462