FR2529880A1 - PROCESS FOR THE PRODUCTION OF PASTE-LIKE FIBROUS MATERIALS, FIBROUS MATERIALS MADE THEREBY AND USE THEREOF - Google Patents

Abstract

PROCESS FOR THE MANUFACTURE OF FIBROUS MATERIALS IN THE FORM OF PASTE, FIBROUS MATERIALS MANUFACTURED ACCORDING TO THIS PROCESS AND THEIR USE. WE MIX 100 PARTS BY WEIGHT OF CERAMIC FIBERS WITH 100 TO 180 PARTS BY WEIGHT OF WATER AND CONTINUING THE MIXING, WE INCORPORATE 4 TO 15 PARTS BY WEIGHT OF BONDING CLAY, AFTER ADDING THE ORGANIC BINDER IN A PROPORTION FROM 2 TO 8 PARTS BY WEIGHT CALCULATED AS SOLID MATERIAL.

Description

Process for the production of pulp-shaped fibrous materials

  fibrous materials manufactured by this process and

their usage.

  The present invention relates to a process for the production of pulp-shaped fibrous materials by means of refractory or incombustible ceramic fibers, clay, optionally other conventional additives, a binder

organic and water.

  A previous patent application P 31 05 593 1-45 of

  the Applicant describes for the manufacture of plastics

  In a process in which a predominant fraction of ceramic fibers is mechanically disentangled, an organic binder is dry-added thereto, relatively low amounts of water are then applied to the mixture, and further clay is added to this mixture. Finally, a solution of an organic binder is incorporated. These materials can be used for the production of non-combustible or refractory molded nieces as well as for the production of extrusion moldings. In this known process, 100 parts by weight of ceramic fibers,

  at most 50 parts by weight of water are added.

  The object of the invention is to provide a manufacturing method for improving the quality of pulp-like fibrous materials of the aforementioned type, these pulp-shaped fibrous materials being particularly suitable for

  for the manufacture of fibreboard by simple

  between rolls, drying and possibly

  The fibrous materials produced according to the invention must also be able to be used as a coating, for example as a material.

  filler for expansion joints.

  To achieve this result, a method is used in which 100 parts by weight of ceramic fibers are blended with 100 to 180 parts by weight of water, and 4 kn is added to 15 parts by weight of binding clay and then the organic binder is added in a proportion of 2 to 8

  parts by weight calculated as solid matter.

  Before incorporation of the bonding clay, it is advantageous to add 2 to 8 parts by weight of A 1203 and / or colloidal silicon dioxide beforehand.

finely distributed.

  At the same time as the bonding clay, from 2 to 15 parts by weight of chromium oxide and / or of titanium dioxide and / or magnesium oxide may be incorporated.

  and / or finely distributed aluminum hydroxides.

  As a connecting clay, it is advantageous

  use of bentonite and as an organic binder for

starch.

  After the introduction of the organic binder, it is advantageous according to the invention to add another 1 to 4

  parts by weight of carboxymethylcellulose It is also

  advantageously according to the invention to add to the mixture a

antifermentiscible product.

  The invention furthermore relates to pulp-shaped fibrous materials which are made by this process and have a shelf life of from

less than 4 weeks.

  The invention furthermore relates to the use of fibrous materials in the form of a paste for the manufacture of panels by simple calendering, drying and possibly heat treatment of the panels. These panels can advantageously serve as filling material for the expansion joints, for example. example between rotary tubular furnace bricks, in which case they must absorb the

  constraints as well as general asbestos

  hitherto used and without the same health hazards as the latter These pulp-shaped fibrous materials pose no health hazard when used for other purposes, in particular as filling for

  expansion joints between the kiln bricks, particularly

  tubular kilns.

  Non-combustible or refractory ceramic fibers

  used in the process according to the invention are

  known compounds, in particular based on aluminum silicates with a particularly high content of A.sub.2 O.sub.3 which can reach from 45 to 95% by weight. According to the envisaged use of the plastics, that is to say the desired degree of

  resistance to fire or incombustibility, it can not only

  also use mineral wool fibers, but it is still possible to use blends of these fibers

  ceramics Ceramic fibers are advantageously used

  in chopped form, that is to say with a length of 1 to 5 mm, but it is also possible to use so-called crushed fibers which have a length of between 10 and 500 μm. The diameter of the ceramic fibers is in general in an order of magnitude of 1 to 25, m and in particular in a range between 2 to 8 Dam It is of course possible to use ceramic fibers

having other dimensions.

  The binding clays employed in the process according to the invention are in themselves known, in particular it is advantageous to use bentonite as a connecting clay. The refractory materials finely distributed and used as possible additives in the process according to the invention, namely aluminum oxide, aluminum hydroxides such as bauxite, titanium dioxide, chromium oxide and magnesium oxide are known to those skilled in the art. By finely distributed materials, it is also understood that

  colloidal substances, in particular sili-

  colloidal lique which is generally in the form of a soil The quantities indicated are, however,

always to solids.

  As organic binders can be used in the

  process according to the invention with organic binders generally

  used, eg spent sulphite liquor in solid or liquid form or starch, The quantities indicated for organic binders always relate to

solids.

  In a preferred embodiment of the method according to the invention, at the end of the manufacturing process is added

  Carboxymethyl cellulose is still

  Boxymethyl can advantageously be added half in the form of viscous solution and half in solid form. In the process according to the invention, the order in which mixing takes place is essential since it makes it possible to obtain a homogeneous mass.

  mixing is usually 10 to 40 minutes.

  As mixing devices, the usual mixers can be used in the process according to the invention and

  In this respect, it has proved particularly advantageous to use

  use the so-called "forced mixing" mixers (Eirich mixers).

  The invention is explained using the following examples in which commercially available ceramic fibers of the following composition were used: Fibers A at 47% A 1203 and 53% SiO 2;

  Fibers B at 95% A 1203 and 5% Si O 2.

Example 1

  In a mixer (Drais mixer), parts by weight of ceramic fibers A and 150 parts by weight of water were introduced. Mixing was carried out for 5 minutes. While stirring was continued, 10 parts by weight of bentonite were added, binding clay and kneaded for a further 6 minutes. As a result, 5 parts by weight of solid starch were added as the organic binder, followed by

  incorporated by mixing for 10 minutes an anti-

  fermentable in sufficient quantity to prevent a

252,880

  fermentation or a mold of the plastic when

storage.

  This material exhibited storage resistance

  more than 6 weeks at normal ambient temperatures.

  By applying it by means of a trowel on refractory bricks, it could advantageously be converted into an elastic flexible layer. When a refractory structure formed by these bricks coated with this plastic material has been formed, the latter once cured and dried acted as a joint filler

of dilatation.

  Examples 2 to 10 The procedure of Example 1 was repeated using the compositions indicated in the following table

Board

Example

  Fiber A Fibers Binder oxide chroma oxide <44 pn Titanium dioxide <44 lmn magnesium oxide <Co O pn Bauxite <63 pine Water Carboxymethylcellulose A 1203 <63 m Sio 2 colloidal

2 3 4 5 6 7

50

50

8 5

12 2

2

140 150 170

1 2 -

2 '2 2 2

2 8

100 25

75

8 4 1-5

3 -

*

8 9

e

2 4-

O120 140

i-O

-I 2

110

  z * 50% added as a 5% solution in water and 50% as a solids form

  The water content of the solution should not be taken into account.

CD c% J

Example 11

  The plastics manufactured in Examples 1, 3 to 5 as well as 8 were placed on a three-roll calender and made into panels of 5 mm thickness. The panels were dried at a temperature of 1100 C and the panels having the compositions 1, 3 and 8 were subjected for 2 hours to a heat treatment at a temperature of

temperature of 180 to 200 ° C.

  In all cases, an excellent material has been obtained for fibreboard which can be used instead of asbestos panels as filler for expansion joints between refractory bricks, especially in rotary tube furnaces. . In the drawing, there is shown a diagram in which is indicated the strength of the panel-shaped material before the composition according to Example 5 compared to the same asbestos comparative material This diagram reproduces the stress caused by the thermal expansion of bricks and decreased by the material of the panels inserted into the joint, a material 2 mm thick, ie a

  2 mm joint thickness being used in this case.

  In this diagram, it can be seen that the panels made of the plastic according to the invention have an identical or slightly improved performance by

compared to asbestos joints.

Claims (8)

  Process for the production of pulp-shaped fibrous materials using refractory ceramic fibers   or incombustible, of clay, possibly other additions   Conventional agents, an organic binder and water, characterized in that 100 parts by weight of ceramic fibers are mixed with from 100 to 180 parts by weight of water, that by continuing the mixing, it incorporates 4 to 15 parts by weight of clay-bonding and then the organic binder is added in a proportion of 2 to 8 parts   by weight calculated as solid matter.   Process according to claim 1, characterized in that prior to incorporation of the binder clay at least 2 to 8 parts by weight of A 1203 and / or   colloidal silicon dioxide finely distributed.   The process according to claim 1 or 2, wherein   characterized by the fact that at the same time as the cutting clay, 2 to 15 parts by weight of chromium oxide and / or of titanium dioxide and / or magnesium oxide are still incorporated.   and / or finely distributed aluminum hydroxides.   Process according to any one of the claims   previous ones, characterized by the fact that bentonite-like clay bond.   Process according to any one of the claims   previous ones, characterized by the fact that   starch as organic binder.   Process according to any one of the claims   preceding, characterized by the fact that after the introduction of the organic binder, 1 to 4 parts by weight are added of carboxymethyl cellulose.   Process according to any one of the claims   preceded by the fact that an agent is added antifermentiscible to the mixture.   8 Dough-shaped fibrous materials manufactured   according to any one of claims 1 to 7.   9 Use of pulp-shaped fibrous materials according to claim 8 for the manufacture of panels   by calendering, drying and optionally heat treatment.