FR2539125A1 - MIXTURE TO MANUFACTURE LIGHT AGGREGATES FOR CONSTRUCTION MATERIALS - Google Patents

Abstract

The mixture is used for the manufacture of light aggregates for building materials and consists of approximately 10% by weight to approximately 80% by weight of clay capable of being expanded from approximately 1% by weight to approximately 5% by weight of recovered oil, the remainder being an additive which may consist of river and / or marine sediments, ash or sludge. The constituents of the mixture are transformed into a high-value product that would otherwise have to be produced using raw materials. The light aggregate made from the mixture is suitable for the production of building stones with good thermal insulation power, as an additive for light construction concrete and as an additive for an insulating coating to improve the insulation, or for insulating mortars.

Description

Mixture to make

of construction.

  Light aggregates for materials The invention relates to a mixture for manufacturing aggregates

  lightweight for building materials.

  Light aggregates are used for example to reduce the weight and quantities in the manufacture of building materials, for example in the manufacture of building stones, light concrete, mortar and the like But for these light aggregates, we needs a high percentage of at least 85% by weight of clay, which is a raw material

valuable.

  The object of the invention is to produce a mixture of the type

  above to reduce the percentage of clay.

  This object is achieved according to the invention in that the mixture provides at nmins about 1% by weight up to 5% by maximum weight

  recovery oil, about 10% by weight up to approx.

  80% by weight of clay capable of being expanded, the

rest being an additive.

  The components of the mixture of the invention are transformed into a product of great value which could not be produced other than by using raw materials. It is also possible to use here as additives substances loaded with harmful products, such as heavy metals, organic impurities and the like which otherwise could only be stored on landfills, since the character

  pollutant of these products prohibits their use in agriculture

  culture With the mixture of the invention, it is possible to manufacture a light aggregate of great value having a low apparent density, a high resistance to pressure and a good heat-insulating power. The light aggregate made from the mixture of the invention is for this remarkable reason

  to make building stones with good capacity

  see thermal insulation, as an additive for lightweight concrete for construction and as an aggregate for insulating plaster

  for additional thermal insulation, or for mor-

  insulating tier The costly disposal of waste is compensated

  seée, according to the invention, by the economic re-incorporation of waste in the politico-economic circuit of food; thanks to the goods thus produced, we can save

  raw materials that should have been processed.

  The invention will be clearly understood on reading the description

  detailed, given by way of example only, of forms of

favorite achievement.

  In a first embodiment of the invention mix

  tion, about 10% by weight to about 80% by weight of expandable clay is used, about 1% by weight to about 5% by weight of recovery oil, the remainder being

  river and / or marine sediments As clay expands

  healthy, we use iridescent clay (Dogger a, Jura) or variegated upper marls (Keuper medium, km 3)

  River and / or marine sediments are obtained by decon-

  tamination of running or stagnant water Sediments

  may be loaded with harmful substances When processing

  following the mixing, these harmful substances are

  surrounded by a sintering skin during the sudden cooling

  so that they can no longer exercise their harmfulness.

  Insofar as the harmful substances pass into the gaseous state before the expansion temperature is reached,

  cadmium for example, they are evacuated and collected in -

  dust filters and the like For this reason, it is not necessary to deliver harmful substances to the sediments obtained during water decontamination,

  which would require complicated and costly operations.

  In a preferred embodiment, the mixture is

  from less than about 30% by weight of clay, from about 68% by weight to about 88% by weight of river sediments

  and / or marine, and about 2% by weight of recovery oil.

  With this mixture, one can make a light aggregate which has

  particularly low bulk density and resistance

  high tance In this mixture, exclusive-

  river sediments or exclusively marine sediments or a mixture of river and marine sediments Preferably, a river or marine sediment is used.

fine grains.

  In another embodiment, the mixture of the invention consists of approximately 10% by weight to approximately 80% by weight of clay capable of being expanded, approximately 1% to 5% by weight of oil recovery, the rest being made up of

  ash and / or sludge As ash, for example,

  full of fly ash consisting mainly of mineral-pulverulent materials which are produced in modern installations of filters and separators of coal-fired power plants. As sludge, red sludge can be used, for example, as it is produced.

  when making aluminum from bauxite.

  The light aggregate made from this mixture is characterized

  increased by its low apparent density The addition of fly ash especially significantly improves the solidity of the aggregate

  light, even compared to the first realization of the mixture.

  In the second embodiment, the mixture may include

  carry only fly ash or only mud, or a mixture of ash and mud In a preferred embodiment, for the mixture is used about% by weight to about 30% by weight of clay, about 68% by weight about 88% by weight of ash and / or sludge and about 2% by weight of recovery oil As clay capable of expansion, it is also possible to use clay

  iridescent or motley upper marls.

  In a third embodiment of the mixture of the in-

  note, about 10% by weight to about 80% by weight of clay is used, about 1% by weight to about 5% by weight

  recovery oil, the rest being fluid sediment

  sea and / or sea and ash and / or sludge, in any desired ratio A preferred composition of this mixture is

  about 10% by weight to about 30% by weight of clay, approxi-

  2% by weight of recovery oil and around 68% by-

  weight at 88% by weight of fine-grained river and / or marine sediments, mixed in all possible relationships with ash and / or sludge The mixing ratios of river and / or marine sediment, and ash and / or sludge depends on the solidity sought for the light aggregate When large resistances are required as for light concrete, a higher proportion of ash and / or sludge is used. Correspondingly, the resistance of the light aggregate decreases when the proportion

ash and / or sludge decreases.

  In all the embodiments, the sediments, the ashes and the sludges are fine-grained in order to obtain a homogeneous mixture. With the mixtures described, the percentage of clay is reduced, which makes it possible to save this raw material of great value In the mixtures of the invention, the major part consists of waste, which therefore does not need to be landfilled, but can be immediately used for the manufacture of aggregates

light.

  Preferably, each of the mixtures described comprises a

2539125

  portion of red mud present in a concentration of

  about 1% by weight to 10% by weight in the mixtures.

  In a particularly advantageous embodiment, the mixture contains blowing agents as an additional constituent. The proportion of clay in the mixture can be reduced depending on the amount of blowing agent added. If, for example, a mixture is added consisting of 70% of additive, for example sediments, 25% of clay and 5% of other additives, 3% of blowing agent, the percentage of clay can be lowered to around 15% and the percentage of additives to be increased up to approximately 77% With the blowing agent, good and significant expansion is obtained during the manufacture of expanded clay with the mixture The various constituents of the mixture are mixed with water, granules, then dried and preheated After drying, the granule is calcined and, in doing so, expanded During this

  each granule takes on its characteristics of aggregation

  light gat The expansion is controlled so that the

  granules already have a closed sintering skin when the former

  expansion begins This prevents the gases necessary for expansion from escaping Thanks to the blowing agent,

  despite the reduced clay percentage, an expan-

  Particularly good and high sion so that the expanded granule has a very low bulk density and a very high resistance to pressure The aggregate produced from the mixture is remarkable for the manufacture of stones of

  construction with good heat insulation, as an additive

  tif to make light concrete for construction and as an additive for insulation to improve insulation

  thermal, or for insulating mortars.

  For mixing, a large part of the waste is also used so that there is no longer any need to eliminate this waste in a costly manner This elimination is replaced

  by the reincoroporation of waste in the political-cycle

  economical commodity and thanks to the goods as well

  produced, we can save raw materials than other-

ment should have been transformed.

  As additives, river and / or marine sediments can be used These additives, which otherwise would have had to be eliminated

  costly, such as contaminated dam sediments

  mined by heavy metals, can now be treated

  to make a high quality lightweight aggregate for material

  Construction materials Thanks to the addition of blowing agent, large quantities of these additives can also be transformed into a light aggregate of great value using

  a small amount of the precious clay raw material.

  In place of river and / or marine sediments or at the same time as these, one can also treat ash and mud The expanded clay has a closed and smooth sintering skin, fine pores uniformly distributed and a great resistance By using the mixture of the invention, one can notably improve the transformation into balls of the expanded clay. For the mixture, about 10% by weight to 80% by weight of expandable clay is used, about 1% by weight to about 5% by weight of blowing agent, about 1% by weight to about 5% by weight of recovery oil, the remainder being river and / or marine sediments (approximately% by weight to approximately 88% by weight) River and / or marine sediments are obtained during the decontamination of running or stagnant waters and they can be loaded with harmful substances These harmful substances are trapped in the sintering skin during the manufacture of expanded clay, so that they can no longer exert their harmfulness As long as these harmful substances pass to

  gas state before the expansion temperature is reached

  sion, like cadmium for example, they are evacuated and collected in dust filters or the like For this reason, it is not necessary to release harmful substances from the sediments resulting from the decontamination of

  waters, which would require complicated and costly operations.

  For another mixture, about 10% to about 80% by weight of clay is used, about 1% by weight to about 5% by weight of blowing agent, about 1% by weight to about 5% by weight of oil recovery, the rest being ash and sludge (about 10% by weight to about 88% by weight) As ash, fly ash can be used, for example

  consisting essentially of powdered mineral substances

  slow, which are produced in modern filter and separator plants of coal-fired power plants. As sludge, it is possible to use the sludge from municipal wastewater

  or industrial sludge, of metallic or organic type.

  The light aggregate made from this mixture is characterized

  rise by a low apparent density The addition of ash

  above all increases notably the resistance of the

  light gat The mixture may only contain ashes or

  as mud, or a mixture of ashes and mud.

  In another embodiment of the mixture,

  about 10% by weight to about 80% by weight of clay suscep-

  tible to be expanded, about 1% by weight to about 5% by weight of blowing agent, about 1% by weight to about 5% by weight of recovery oil, the remainder being sediment

  river and / or sea, and ash and / or sludge (approx.

  (10% by weight to 88% by weight) River and / or marine sediments can be mixed with ash and / or mud in all possible reports

  of mixing depend on the resistance sought for the approval

  light gat If high resistances are required, as for example for light concrete, a higher proportion of ash and / or sludge is used. Correspondingly, the percentage of ash and / or sludge is lower if

  the resistance of the light aggregate should be lower.

  In all the embodiments, the sediments, ash and sludge are fine-grained, in order to obtain a homogeneous mixture.

  As blowing agent, an alkali binder is preferably used

  linen which allows the constituents of the mixture to be firmly assembled Preferably, it is used as a blowing agent

  cements, for example Portland cement.

Claims (8)

Claims.   1 Mixture for manufacturing light aggregates for building materials, characterized in that the mixture comprises at least 1% by weight up to approximately 5% by maximum recovery oil, approximately 10% by weight to approximately 80% by weight of clay likely to be expanded, the rest being an additive.   2 Mixture according to claim 1, characterized in that it comprises less than about 30% by weight of clay, about 68% to about 88% by weight of additive and about 2% of recovery oil. 3 mixture according to claim 1 or claim 2, characterized in that iridescent clay is used as clay (Dogger a, Jura): 4 mixture according to claim 1 or claim 2, characterized in that use is made as marl clay variegated (average Keuper, km 3).   Mixture according to any one of Claims 1 to 4,   characterized in that ash is used as additives and mixed sludge.   6 Mixture according to any one of claims 1 to 4,   characterized in that sediments are used as additives fluvial and / or marine.   7 mixture according to any one of claims 1 to 6,   characterized in that the mixture comprises river and / or marine sediments and ash and / or sludge in any report you want.   8 Mixture according to any one of claims 1 to 7,   characterized in that it contains red mud in a 2539125   concentration from about 1% by weight to about 10% by weight.   9 Mixture to make light aggregates for materials   Construction materials, in particular according to claim 1, characterized in that the mixture comprises approximately 1% by   weight to about 5% by weight of blowing agent.   Mixture according to claim 9, characterized in that   the blowing agent is an alkaline binder.   11 Mixture according to claim 9 or claim 10,   characterized in that the blowing agent is cement.   12 Mixture according to any one of claims 9 to 11,   characterized in that the mixture contains bulking agents   flants in a range between about 2% by weight and about 4% by weight.