[0001 ] Firefighting foam with a mixture of insulating and fire-retardant powders

Technical Field

[0002] The technical field of this invention relates to chemical materials firefighting Classifications of ABC group Fires (dry objects, gases, solvent, alcohols, aromatic and petroleum derivatives).

Background Art

[0003] Patent No. W02006132568 titled FIRE-EXTINGUISHING COMPOSITION is a type of firefighting foam based on organofluorine compounds with additives of magnesium chloride, calcium, ammonium acetate, ethylene, and propylene glycol to form an aqueous layer on the surface of combustible liquids. During extinguishing, this foam forms on the surface of the liquid, which has a water layer that absorbs heat and prevents the supply of oxygen to the fire and backdraft. On the other hand, it prevents the corrosion of tanks. The resulting foam has a specific gravity of 1 g/l and a density of 1 .2 g/cm3.

[0004] Several raw materials (non-fluorinated compounds) in the production of firefighting foam are common in this invention and the claimed one. But these two inventions differ in the following:

[0005] 1 - The organ fluorine compounds that are present in this invention are phased out according to the global environmental protection order and cannot be used or even stored in the firefighting system.

[0006] 2- Fluorinated foam and other foams have a fixed formula and cannot be changed in concentration and formula in fire extinguishing. But in the claimed invention, the percentage and composition of the special foam can be changed in the fireplace.

[0007] 3- Fluorinated foam is only used to extinguish petroleum liquids and does not work on other combustible materials such as wood. But the claimed invention extinguishes all ABC fire groups at the same time. [0008] 4- The mixing system of the claimed invention is modular and continuous in different sizes and dimensions.

[0009] 5- In the claimed invention, the raw materials are installed on the device as long-term storage and are mixed only during use.

Technical Problem

[0010] The existing fire extinguishing materials just interrupt one side of the fire triangle and cannot be applied for all temperatures and places. On the other hand, given the fact that the different two sides of the triangle are active, there is a high probability that the backdraft or the existing vapors and smoke will result in substantial human and financial losses.

[0011] 1- Water characterized with a density of 1 kg/m3 is one of the fire extinguishers that evaporates at 100 C and is used only for dry objects and is not easily available. When used in buildings, it causes an increase in resistive load and ultimately collapses. At the same time, the level of water contamination is important for this use, for example, water should not contain heavy salts or impurities and coarse particles.

[0012] 2- Firefighting foam with a density of 0.02 to 0.10 kg/m3 is vaporized at a temperature of about 120 C and given the presence of air in its bubble and the thinness of the membrane and low density; it is moved by the wind and not precipitated on the surface of the fire. It has less throwing power than water and is mostly applied to petroleum liquids. Heavy and hard water or salty sea water cannot be used to produce foam. Also, it cannot be used at temperatures above 600 C.

[0013] 3- The firefighting powder is a combination of bicarbonates and carbonates with waterproof materials with a density of 1 kg/m3. It is used only to extinguish the fire at the time of its onset and a close and visible distance. The powders decompose at 70 to 120 C and emit carbon dioxide gas and cannot be used in large fires. Powders are often lumped inside the capsule and can no longer be used. [0014] 4- Sometimes two or three of the above substances are used together, however, they do not have the desired result and they neutralize each other's effect. These extinguishers are not rechargeable on site.

[0015] 5- Water, powder and fire extinguishing foams each separately are almost ineffective at temperatures above 500 C and at long distances.

[0016] 6- The consumption of these materials is very high and it pollutes the environment a lot during firefighting.

[0017] 7- Sometimes adverse environmental effects can be seen in firefighting foams. Organofluorine compounds in firefighting foams have been phased out by the order of global environmental protection and cannot be used or even stored in the firefighting system.

[0018] 8- Fluorinated foam and other foams have a fixed formula and cannot be changed in concentration and formula in fire extinguishing.

[0019] 9- Foams, including fluorinated foam, are only used to extinguish petroleum liquids and do not work on other combustible materials such as wood.

[0020] 10- To spray the firefighting foam, it must have a special nozzle head and they are not effective without a nozzle head.

Solution to Problem

[0021] Since burning means the reaction of oxygen with a substance in the vicinity of heat in the conditions required for oxidation, the special foam produced by applying its properties to the fire interrupts or destroys the complete oxidation reaction conditions and shortens the distance and time to reach these conditions which is called backdraft.

[0022] While using special foam in fire extinguishing, first of all, the special foam reaches the surface of the combustible material, separates the flame from the surface of the combustible material, then by increasing the boiling point, it increases the stability of the bubble against high-temperature fire and the possibility of more effectiveness on the combustible material. Also, the gases produced after the solution evaporates cause the fire to suffocate and cool down and dilute the oxygen around the combustible material. On the other hand, after covering the surface of the dry material, since part of the extinguishing material penetrates the dry material, it prevents backdraft. When physical and chemical changes occur in a material, therefore, the burning or oxidation conditions also change.

[0023] By dissolving special powder and special foam in water, while changing its nature, special foam is created which has new characteristics. The new special foam features include the following:

[0024] 1- Increasing the boiling and melting point of special foam due to the presence of special powder.

[0025] 2- It changes or destroys the conditions of the oxidation reaction.

[0026] 3- Separating the flame from the fire surface by the stable bubble in the special foam.

[0027] 4- Creating a distance between the combustible material and the flame as a result of preventing oxygen from reaching the combustible material.

[0028] 5- The special powder contained in the composition of the special foam decomposes after absorbing the heat from the fire and produces the cooling and suffocating gases CO2 and ammonia. On the other hand, the amount of oxygen around the diluted combustible material decreases.

[0029] 6- The special powder present in the special foam after contact with fire, while sticking to the surface of the combustible material and absorbing heat, creates a bulky insulating, and fire-retardant layer on the surface of the combustible material.

[0030] 7- The amount of penetration of extinguishing solution in the combustible material, especially solids, increases.

[0031] Given the compounds used in the special foam, after proximity to the heat, the volume of the solution increases and causes the flame to separate from the fuel. To extinguish dry objects (such as wood and forest products), the same composition of special powder and water is sufficient and does not need foam or bubbling liquid. [0032] The bubble in the special foam increases the volume of the extinguishing material and also covers a larger surface of the burning material, giving more time to the firemen to maneuver. The water that can be used in this composition does not need to be purified and light, heavy, purified, well, or river, and seawater can be used.

[0033] Ingredients of dry powder:

[0034] To achieve the required properties, the special powder is composed of the following ingredients:

[0035] 1- 25-40% filler: potassium carbonate is the best option for this property, but due to its high cost, 50% of its composition with calcium carbonate can be used.

[0036] 2- 25 - 35% Extinguisher: Potassium bicarbonate is the best option for this property. But a combination of it with sodium bicarbonate or potassium bicarbonate can be used.

[0037] 3- 1 -2% anti-corrosion materials: Ammonium acetate is used in order to prevent the corrosion of containers for transporting and storing fire extinguishers. It is also possible to use calcium acetate-potassium chromate.

[0038] 4- Materials for creating a separating layer on the surface of 1 -2% petroleum derivatives fuels: the best option for creating this condition is magnesium chloride, but sodium chloride, calcium chloride, or ammonium chloride can be used.

[0039] 5- 1 -3% anti-clumping and moisture absorption and long-lasting powder: Zinc stearate is the best option for this property, but zinc stearate, magnesium stearate, or stearic acid can be used.

[0040] 6- 3-5% fire retardant and thermal insulation materials: aluminum sulfate is the best option for this property, but sodium sulfate, calcium sulfate, zinc sulfate, sodium silicate, micro silica, perlite, zeolite, or talc can be used.

[0041] 7- 3-5% thermal retardant: aluminum oxide is the best option for this property, but aluminum trihydroxide or aluminum peroxide or aluminum potash or vermiculite or mica can be used. [0042] 8- 5-10% bulking materials under heat: starch is the best option for this property, but polycarbomer or polysaccharide or carboxyl methyl cellulose or hydroxypropyl methyl cellulose, or gluten can be used.

[0043] 9- 1 -2% thickener and adhesive: xanthan gum powder is the best option for this property, but guar gum can also be used.

[0044] 10- 5 - 10% extinguisher: Ammonium monophosphate is the best option for this property but mono ammonium sulfate can be used.

[0045] Ingredients of foam producing liquid:

[0046] To achieve the required properties, the special foam consists of the following compounds:

[0047] 1- 10-30% foaming agents: sodium lauryl ether sulfate is the best option for this property, but sulfonic acid or SLS or betaine, or ethoxylated alcohols can be used.

[0048] 2- 2-5% bubble stabilizers: magnesium sulfite is the best option for this property, but aluminum sulfate or sodium sulfite, animal and plant protein concentrate, can be used.

[0049] 3- 1 -2% thickener and adhesive materials: xanthan gum solution is the best option for this property, but guar gum or starch can also be used.

[0050] 4- 2-5% butyl glycol ether as a water surface tension reducer, is the best option for this property.

[0051] 5- 50 - 70% water

[0052] To produce a fire extinguishing agent, 48% water wt, 48% wt of special powder, and 4% wt special foam liquid are mixed. After the materials are mixed and the wind blows, the foam liquid volume increases and its volume increases to 50% of the total volume of the material formed.

[0053] Bulking the mixture can also be done using a foaming nozzle head. By changing the amount of dry powder, foam liquid, and water, it is possible to reach a density between 50 and 1000 kg/m3, which can be changed based on the type of fire. Advantageous Effects of Invention

[0054] 1 - Making physical and chemical changes to prevent or stop the conditions of oxidation or burning reactions (temperature - concentration - contact surface - heat transfer and mass transfer).

[0055] 2- The possibility of changing the composition of components in order to obtain different densities (between 100 and 1000 kg/m3).

[0056] 3- Heat removal from the combustible material.

[0057] 4- Decomposition and emission of CO2 and ammonia gas

[0058] 5- Being soluble in water and rising the boiling and melting point and creating cooling and diluting properties of oxygen.

[0059] 6- Adhesiveness and desirable density to reach the surface of the combustible material and its durability.

[0060] 7- Making stability and thermal resistance in foam bubbles.

[0061 ] 8- Ability to re-dissolve in water, after use in a fire.

[0062] 9- The special foam can be changed in percentage and composition in the fireplace according to the type of fire.

[0063] 10- It is possible to mix special foam in the form of a modular and continuous in different sizes and dimensions.

[0064] 11 - The possibility of long-term storage of basic items on the device and use when needed, without the need for annual charging.

[0065] 12- This special foam can be used at any time after the start of any temperature of the fire and has the same efficiency.

[0066] 13- The special foam absorbs all hot gases and vapors caused by fire.

[0067] 14- The special foam can be sprayed by a mono pump or fire pump or water pump or air pressure available in capsules or larger tanks with a nozzle and transferred in a pipe to any distance and height and can be carried with a jumbo bag and by helicopter on reservoirs and forests.

[0068] 15- The special foam for spraying does not need a foam producer nozzle head and transfers it with a normal hose. [0069] 16- The foam is self-extinguishing and can be used as a fire extinguisher in warehouses, pastures, and forests so that if it is sprinkled on combustible materials a little ahead of the fire, it will extinguish itself when the fire reaches that area.

[0070] 17- The special foam has materials that expand due to heat and increase the distance between the flame and the combustible material. These materials, while absorbing heat, prevent oxygen from reaching the surface of the fire.

[0071] 18- The special foam layer formed on the combustible material can be washed and cleaned with wind and water or tissue.

[0072] 19- The special foam turns into fertilizer after being released into the environment and mixed with the soil.

Brief Description of Drawings

[0073] Figure 1 : Schematic view of preparation of firefighting foam with a mixture of insulating and fire-retardant powders

Examples

[0074] To use this fire extinguishing foam, the three materials of water, special powder, and special foam are first mixed in the mixer and then enter the mono pump. To spray from special foam, you can use the pressure of a capsule or cylinder with different volumes or transfer it to the fire with a bag.

[0075] Raw materials may be stored on the device for a long time and are mixed only during use. As a result, there is no cost for the annual charge.

Industrial Applicability

[0076] 1 - Refineries and oil wells and gas stations and all petroleum derivatives

[0077] 2- Paint, solvent, and alcohol factories

[0078] 3- Fabric, textile, wood, paper, and rubber factories

[0079] 4- Forests and rangelands

[0080] 5- Urban fire department and buildings and facilities

[0081] 6- Wooden and fiberglass ships and shipbuilding

[0082] 7- Usable in the group of porous ABC fires