GB2426975A - Binder for mineral aggregates - Google Patents

Abstract

A binder for mineral aggregates and sands comprises of a) an acid or alkali and/or salts; b) a water soluble or miscible fuel and c) water. The fuel may be ethyl alcohol, the acid phosphoric acid, the alkali may be sodium hydroxide and the salt may be sodium silicate, a) may be present in 10-70 wt%, b) 30-80 wt%, c) 1-40 wt%. Also disclosed is a method or process by which durable building materials or products can be made by using the binder as previously described, which is based on the ignition of the binder which has been blended with the mineral aggregates. This causes a low temperature surface calcinations of the minerals. The resultant reactive surfaces unite under the effect of the binding agent.

Description

IMPROVED BUIDING CONSTRUCTION

The present invention relates to an improved approach for the construction of buildings and building products.

This improved approach is based on the use of a range of novel binding agents together with conventional mineral aggregates in a novel process of construction.

There are many situations in which buildings and building products need to be constructed simply and economically using local mineral aggregates such as rock, stone, gravel and sand to provide durable constructions.

The present invention provides a novel binding agent and a novel method of building and building product construction. This binding agent and method of construction is specifically designed to be suitable for use with local mineral aggregates so as to produce durable constructions, for example homes, simply and cost effectively. 2.

Conventionally, durable buildings are constructed out of for example, fired bricks or cast concrete or concrete blocks, made from locally available mineral aggregates, sands and clays. In each case, a cementjtjous substance is used to bind the structure. In such conventional Construction the binder usually used is Portland Cement. This is a calcium aluminium silicate which sets when water is added. It is used in the construction of durable buildings in the form of a wet cement slurry. This is either used to produce concrete by the addition of mineral aggregates, or to produce mortar by the addition of mineral sands. Concrete may then be used to cast building blocks, or be poured between shuttering to produce monolithic walls for durable buildings. Mortar may be used to bond either cast concrete blocks or fired bricks.

It will be seen from the above paragraph that Portland Cement is conventionally a vital material in the construction of durable buildings. Indeed this is the case and there are Portland Cement manufacturing industries in all advanced nations.

Portland Cement is an adequate binding material for the construction of durable buildings.

However, its manufacture involves the consumption of globally significant quantities of fuel, which in turn produces significant quantities of carbon dioxide, a suspected contribution to global Warming. 3.

It has now been discovered according to the present invention, that durable buildings can be constructed in many situations using conventional materials, that is local mineral arisings, together with a novel binding agent, which functions as a replacement for Portland Cement, in a novel method of construction.

The invention described herein provides for the manufacture of this novel binding agent and its method of application. This is to say a novel system for the construction of durable buildings and durable building products.

One of the many advantages of the present invention, is that the manufacture and use of this novel bonding system produces less carbon dioxide than the Portland Cement method.

The basis of the present invention is the recognition that many minerals frequently used as the principle local component of durable buildings, can be bonded using the binding material defined herein as a replacement for Portland Cement. This recognition forms the basis of an ecologically and economically advantageous approach to the construction of durable buildings, in many situations, globally 4.

Essentially, the novel binding agent defmed in the present invention is a composition of matter produced when three essential material ingredients are blended together. These three essential materials will be defined in the following paragraphs.

The first essential material is a fuel. This may be either in the form of a solid or a liquid. An example of a solid form of fuel which can be used, is coal dust. However, a liquid fuel is preferred.

Examples of liquid fuels which can be used include crude oil, petroleum fractions and heavy oil fractions. However, a liquid fuel which is miscible or soluble in water is preferred. Examples of water miscibles or soluble fuels which can be used include organic chemicals for example: alcohols, aldehydes, ketones, esters and ethers. Alternatively, a non water soluble fuel such as petrol can be used if additives are added that render it miscible with water. The preferred fuel is industrial ethyl alcohol. This is also called methylated spirit because it is made to contain methyl alcohol as well as ethyl alcohol. In practice any economically available ethyl or methyl alcohol or blend containing these organic chemicals can be used as the water miscible or water soluble fuel in the present invention.

The second essential material is water. This may be present in the industrial ethyl alcohol or it may be added as a separate ingredient to the mixture.

The third essential material is a water soluble acid, alkali or salt or a combination of acids or alkalis or salts, or a mixture of either acids and salts or alkalis and salts. 5.

Examples of this third essential material include the following acids, hydrochloric acid, sulphuric acid and phosphoric acid. Examples of alkalis that can be used include the following, sodium hydroxide, ammonium hydroxide, potassium hydroxide. Examples of salts that can be used include, ammonium phosphates, magnesium chloride and sodium silicate.

In addition to these three essential materials the novel binding agent may contain other materials that serve the purpose of modifying or improving the bonding or aid the application of the binding agent.

The novel binding agent is the result of blending the three essential materials together. The novel binding agent can therefore be defined as an alcohol water solution containing acid and or alkali and or salt materials.

The novel binding agent may be blended prior to use or blended at the time and or location of use.

It is a feature of the present invention that the novel binder contains a fuel which is either soluble in water or miscible with water. This allows for complete distribution of the fuel throughout the cast building product or building structure. This in turn induces complete and even combustion and calcination and bonding. 6.

The novel binding agent will usually be a liquid but alternatively the novel binding agent can be a sluriy or a damp solid or even a dry solid if it contains other materials that serve the purpose of absorbing the binder or modifying or improving the bonding or application of the binder.

Concentrated binder may for example be absorbed on an absorbent. In such cases the novel binder solid or slurry may be diluted with water at the time and or location of use.

The novel binding agent is to be used as a building and building product bonding agent. It is normally applied to iocaliy available mineral aggregates and or sands. The acid or alkali or salt content of the novel binder is selected to react with the specific mineral aggregate or sand to be used.

It should be appreciated that the present invention covers a range of binders not just a single version of the novel binder. Throughout this range all the binders are based on a standard miscible or soluble fuel water mixture, plus chemicals which may be acids and or alkalis and or salts. The present invention covers a range of formulas for such novel binders.

I have researched the use of novel binding agents with a range of mineral arisings such as are typically used in the construction of durable buildings. My research has shown that versions of the novel binding agent can be used to bond most commonly used mineral aggregate building materials, provided that the formulation of the binder is chosen to be suitable for use with the specific mineral aggregate. 7.

The range of formulations for the novel binding agent will now be described.

Many calcarious mineral aggregates are available and are used as building materials in the construction of durable buildings. Such arising as limestone, coral sands and marble are examples of this category of mineral arisings. An example of a formulation for the novel binder for this category of arisings is based on the standard miscible or soluble fuel water mixture plus phosphoric acid or a salt that yields phosphate upon thermal decomposition, for example an anilnonulTi phosphate.

In addition to the above mentioned relatively pure forms of calcarious minerals there are many other mixed carbonate and carbonates mixed with silica minerals used as building materials in the construction of durable buildings. Such arisings as dolomitic limestone and cherts are examples of this category of mineral arisings. An example of a formulation for the novel binder for this category of arisings is based on the standard miscible or soluble fuel - water mixture plus magnesium chloride.

Many silica or alumino silicate mineral aggregates are available and are used as building materials.

Such arisings as granite, basalt, gritstones, sandstones, silica sands and alumino silicate clays are examples of this category of mineral arisings. An example of a formulation for the novel binder for this category of arisings is based on the standard miscible or soluble fuel - water mixture plus sodium or potassium silicate. 8.

I have also researched the use of semi synthetic and synthetic minerals in conjunction with the novel binder and found that substances such as Pulverised Fuel Ash and various Metallurgical Slags can be used in place of natural minerals.

My research into the novel binding agent is continuing. The above specific formulations of the novel binding agent for specific categories of mineral building materials are only presented as

examples.

Overall, the component parts of compositions of matter, as described in the present invention, for use in the construction of durable buildings and building products are as follows: Mineral aggregate and or sands.

A version of the novel binding agent.

Other additives.

Other additives may include materials which improve the durable buildings and building products such as pigments, frost damage preventative additives, insulative aggregates, rheology modifiers and decorative aggregates. 9.

Basically however, the process for manufacturing durable buildings and building products, as described in the present patent, is based on mineral aggregates plus versions of the novel binding agent.

The way in which mineral aggregates plus versions of the novel binding agent are used to produce durable buildings and building products will now be described.

The mineral aggregates and or sands are mixed with the novel binding agent to form a slurry. This sluny is then cast into either moulds or other containers to shape blocks, or between shuttering or other containment system to form a monolithic structure.

A cold set ensues after which the mould or shuttering can be removed.

The shaped building material is then ignited so that it burns in a controlled manner. This low temperature surface calcination action is caused by the presence in the cold cured building material of the miscible or soluble fuel. This low temperature surface calcination brings about the final set of the building material. The temperature involved is between 800 C and 1000 C. 10.

Chemically, the cold and final sets are caused by complex reactions involving the attack by the acid, alkali and or salts on the mineral aggregate surface. This produces insoluble chemicals for example phosphates, sulphates, carbonates, oxides, oxychiorides, aluminates and silicates, depending on the mineral aggregates involved and the version of the novel bonding agent used.

The physical effect achieved upon cooling is a strongly bonded durable structure composed of chemically surface bonded minerals in the form of building blocks or monolithic building structures.

The advantages of this proposed system for the construction of durable buildings and building products will now be described: The proposed materials, based on the novel binding agent and use of locally occurring mineral aggregates and sands, is ergonomically efficient which is to say that only small quantities on non indigenous materials are involved.

The proposed process based on ignition of the mixture to effect low temperature surface bonding calcination of the building or building product, is ergonomically efficient and simple to achieve. 11.

The resulting buildings and building products are as durable or more durable than the corresponding buildings and building products made from Portland Cement.

Additionally, the process defined herein produces significantly less carbon dioxide than the manufacture of Portland Cement.

The materials used to produced the novel binding agent is only marginally more expensive than Portland Cement and this minor economic disadvantage is overturned by the ergonomic savings involved in the proposed process in many situations globally.

Taken together this novel composition of matter, defined herein as a range of novel binding agents, and this novel process defined herein as ignition of shaped cold cured buildings and building materials, to induce a low temperature surface bonding calcination, is a major advance in the construction of durable buildings and building products. 12.

A range of formulas for the novel binding agent can be defined in terms of the percentage by weight of each of the three essential material ingredients namely, fuel, water and chemical. This range of formulas is independent of the specific chemical used in each specific version of the novel binding agent, which is to say that the weight used remains within the same range: Fuel 30kg to 80kg per 100kg of ready to use binder.

Water 1 kg to 40 kg per 100kg of ready to use binder.

Chemical 10kg to 70kg per 100kg of ready to use binder.

Within these ranges, the following are examples of preferred novel binding agents: Industrial alcohol 60kg Water 10kg Industrial concentrated Phosphoric acid 30kg This version of the novel binder can be used with calcarious limestone aggregates and sands.

Industrial alcohol 60kg Water 30kg Magnesium chloride 30kg This version of the novel binder can be used with dolomitic limestone aggregates and sands. 13.

Industrial alcohol 60kg Water 30kg Sodium silicate 30kg This version of the novel binder can be used with silicate containing aggregates and sands.

I'he above relative proportions may be varied. However, sufficient Industrial Alcoihol must be present for the blended liquid mixture to ignite and burn in a controlled manner when blended into a slurry with the bulk mineral component.

In broad terms I may describe my invention in two parts: A novel compostion of matter, which is a binding agent for minerals and contains: Industrial alcohol Water Acids, alkalis and or salts. 14.

A novel process or method of manufacture of durable building materials, called Low Temperature Surface Bonding Calcination which involves: Slurrying building aggregates with the novel binder.

Casting the desired form from the slurry.

Allowing the cast form to set in the cold state.

Removing any moulds or formers.

Igniting the cast shape.

Thus calcining the cast shape.

Allowing the durable cast shape to cool.

The combination of the novel binder and the Low Temperature Suraface Bonding Calcination of the binder blended with a mineral aggregate mixture, can be used to produce: Monolithic building structures.

Calcined building blocks.

Building mortar.

This composition of matter and process of manufacture of durable building materials and products can be conveniently used and is an alternative procedure to the maufancture and uscage in building of Portland Cement. 15.

The reader's attention is directed to all papers and documents which are filled concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings) and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of the features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the detail of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any one or more novel combination of the steps of any method or process so disclosed. 16.

Claims (12)

1. A binder for mineral aggregates comprising in combination (a) acids or alkalis andlor salts, (b) water miscible or water soluble fuel, (c) water.

2. A binder for mineral aggregates according to claim 1, wherein the proportions by weight percent of the components to each other are:

3. a) Acids or alkalis and/or salts 10% to 70%.

4. b) Water soluble or water miscible fuel 30% to 80%.

5. c) Water 1% to 40%

6. A binder for mineral aggregates according to claims 1 and 2 wherein the water soluble fuel is industrial ethyl alcohol.

7. A binder for mineral aggregates according to claims 1, 2 and 3 wherein the acid is phosphoric acid.

8. A binder for mineral aggregates according to claims 1, 2 and 3 wherein the alkali is sodium hydroxide. 17.

9. A binder for mineral aggregates according to claims 1,2 and 3 wherein the salt is sodium silicate.

10. A method or process by which durable building materials and products can be made using the binder for mineral aggregates according to any preceding claim, which is based on the ignition of the binder, which has been blended with mineral aggregates.

11. A binder for mineral aggregates substantially as described herein:

12. A method of producing durable building products substantially as described herein.