ES2313838B1 - SYSTEM FOR THE ELIMINATION OF HYDROGEN FROM THE INSIDE OF BOYAS ESTANAS AVOIDING THE FORMATION OF EXPLOSIVE ATMOSPHERES. - Google Patents

Abstract

Hydrogen removal system interior of watertight buoys avoiding the formation of atmospheres explosive

The present invention refers to a hydrogen removal system inside buoys waterproof (1) comprising at least 1 solar panel or other source of renewable energy (2), at least 1 rechargeable battery or accumulator (3), at least 1 electronic system (4) and at least 1 catalyst solid (5). Furthermore, the present invention refers to the use of system to prevent the formation of flammable atmospheres or explosives and the catalyst construction procedure of the system.

Description

Hydrogen removal system interior of watertight buoys avoiding the formation of atmospheres explosive

Field of the Invention

The present invention relates to a system of elimination of hydrogen accumulated inside instrumented buoys waterproof with solar panels that use rechargeable batteries when use of said system for the removal of hydrogen and at a Hydrogen removal procedure in waterproof buoys avoiding the formation of explosive atmospheres.

Rechargeable batteries used as accumulators in sealed instrumented buoys with solar panels produce a certain amount of hydrogen that should recombine totally. However, in practice a certain amount is free of hydrogen which, given the tightness of the buoys, leaves accumulating until reaching concentrations that can reach the flammability or explosive limit. Therefore, it is done it is necessary to devise a system that eliminates the hydrogen accumulated inside  of the buoy to avoid explosive atmospheres that may cause accidents in its use or handling.

Background of the invention

A solution to the problem of hydrogen accumulation in sealed buoys is the selective oxidation of hydrogen generated at room temperature (<30 ° C) with the oxygen in the air to produce water vapor, which is totally harmless for the operation and handling of the radiobeam, so that the formation of an explosive atmosphere inside is avoided. The oxidation of hydrogen with oxygen or air at low temperature is a catalytic process that is carried out on heterogeneous catalysts, constituted by substrates of inorganic nature on which nano-sized particles of transition metals are deposited. The best hydrogen oxidation catalytic systems consist of noble metals (Pd and Pt) highly dispersed in a porous support with a high specific surface, mainly alumina. However, since the temperature required in this application is lower than the usual ones in this type of reactions, it is essential to incorporate a promoter that increases the catalytic activity under extremely mild conditions in which the radiobeam operates. The specialized literature indicates that the most suitable catalytic systems for this purpose are transition metal oxides, especially iron or manganese (US 6,048,509, MC Alvarez-Galvan et al ., Catalysis Communications 4 (2003) 223).

It is known from the patent ES 2 068 223 T3 a device to remove hydrogen and contaminants from a mixture soda, particularly in case of reactor accidents nuclear. For the removal of hydrogen the device makes use of a catalyst arrangement based on a support material which is coated with an oxidation catalyst material of hydrogen. Given the size and complexity of the device and the accumulated amounts of hydrogen, said invention is not suitable for Its application in solar buoys.

Thus, the current technique needs to have a new procedure capable of eliminating the hydrogen that is generated inside sealed radioboyas and, therefore, avoid formation of an explosive atmosphere. The achievement of this objective is a substantial improvement in safety and handling of this kind of buoys. In addition, the load of the waterproof radioboyas It is much more efficient if this problem is eliminated.

Description of the invention

The present invention provides a system for the removal of hydrogen from the inside of waterproof buoys (1) (Figure 1) comprises at least 1 solar panel or other source of renewable energy (2), at least 1 rechargeable battery or accumulator (3), at least 1 electronic system (4) and at least 1 catalyst solid (5). Furthermore, the present invention refers to the use of system to prevent the formation of flammable atmospheres or explosives and the process for the elaboration of the catalyst of the system. In this way the formation of atmospheres is avoided explosive by reaction of hydrogen with oxygen in the presence of a solid catalyst

These solid catalysts are based on noble or semi-noble metals added on a High surface specific support. Together with noble metals, add other compounds to increase the reaction rate. In general, said compounds will be transition metals (iron, manganese, cobalt, nickel, chromium), preferably in the form of oxide.

The solution of the accumulation problem of hydrogen consists of the inclusion within the buoy of a certain amount of said catalyst material.

As detailed in this document, the problem of eliminating the hydrogen generated by the rechargeable batteries (3) used in solar buoys.

The waterproof radio hoists (1) in general are made of plastic (polypropylene / polycarbonate) and contain a electronic system (4), accumulator batteries (3) and panels solar (2) that recharge the batteries.

Rechargeable batteries (3) are used as accumulators of energy obtained from solar panels. These batteries include a hydrogen recombination system with oxygen to control the amount of gas generated during use normal. Hydrogen that does not become recombined is expelled by the battery through a low pressure ventilation system. Although these are small amounts of hydrogen, the tightness of the buoys makes it possible to reach concentrations that reach the limit of flammability or explosiveness. This supposes  that a spark, a breakdown, a short circuit in the system electronic (4) or overheating of the buoy can cause explosion, with the consequent risk to personnel and material that is in the vicinity.

The purpose of the present invention is to eliminate or reduce the amount of hydrogen stored in a buoy until concentration values that depart from the limits of danger in order to avoid accidents and increase substantially the usefulness of the buoys. To this end the invention proposes a simple solution according to claim one.

Until now the solution applied It usually consisted of sealing the batteries with resins. The problem with this method is that when the sealing is not perfect hydrogen concentrations appear much higher than that would be normal given the operating conditions of the buoy, greatly increasing the risk of accident.

In this invention it has been discovered that the addition of solid catalysts (5) based on noble metals or semi-noble added on a high stand specific surface result in the removal of hydrogen from the inside the waterproof radio buoys avoiding the formation of explosive atmospheres. This end is achieved through selective oxidation of hydrogen with oxygen from the air to ambient temperature (<30 ° C) to produce water vapor, which It is totally harmless for the operation and handling of the waterproof radio-buoy, so that the formation of an explosive atmosphere inside.

The oxidation of hydrogen with oxygen or air at low temperature is a catalytic process that is carried out on heterogeneous catalysts, consisting of substrates of inorganic nature on which particles of nanometric size of transition metals. The best systems hydrogen oxidation catalysts are constituted by noble metals (palladium and platinum) highly dispersed in a high specific surface porous support, mainly alumina. However, since the temperature required in this application is lower than usual in this type of reactions, it is essential to incorporate a base catalyst promoter that increases the catalytic activity in the conditions extremely soft in which the radiobuoy operates.

The catalyst is prepared by addition to the support of a noble or semi-noble metal belonging to the Groups VII to XI of the periodic system, preferably: palladium, platinum, silver, gold, rhodium, iridium, ruthenium, osmium, or a combination of several of these metals. The most suitable are the palladium or a combination of palladium with another metal. The amount of supported metal can be found between 0.001 and 10% in weight relative to the support, preferably between 0.01 and 5% in weight. The metal can be added by any of the known techniques of preparing metal catalysts supported, for example: impregnation, absorption, exchange ionic, etc. Any type of impregnation can be used of salt that is soluble in the solvent used in the addition of Metal such as: acetates, nitrates, halides, oxalates, etc.

Other noble metals will add others compounds to increase the reaction rate, in general transition metal compounds (iron, manganese, cobalt, nickel, chromium ...), preferably in the form of oxide. The proportion mass between the noble or semi-noble metal and the other transition metal can be found between 1 and 100, preferably between 10 and 25. The compound metal addition of transition can be done by any of the techniques known preparation of supported metal catalysts, for example: impregnation, absorption, ion exchange, etc. For the impregnation can be used any type of salt that is soluble in the solvent used in the addition of the metal as: acetates, nitrates, halides, oxalates, etc. Compound addition Transition metal can be done consecutively or Simultaneous with noble or semi-noble metal.

The supports used are high surface specific (> 50 m2 / g). They can be used as supports high surface graphite, activated carbon, carbon black, alumina, amorphous silica, structured silica, zirconium oxide, zeolites and zeotypes, among others.

These catalysts must be pretreated prior to use. The precise method of pretreatment depends of the nature of the compound used and the solvent used but, in general, it consists of heating the catalyst initially prepared in the presence of an inert gas such as nitrogen, argon or carbon dioxide, or in the presence of a gas that contain oxygen, for example air, or a successive treatment in an inert and oxidizing atmosphere. The temperature of Pretreatment is not critical and can vary between 200 and 1000 ° C, with a duration between 1 and 48 hours.

Additionally, these solids can be subjected to an activation The activation method consists of the heating of the catalyst initially prepared in the presence of a reducing gas, such as a gas containing hydrogen at a concentration between 0.1% and 100% in the presence of a gas inert such as nitrogen, argon or carbon dioxide. Temperature activation is not critical and can vary between 50 and 600 ° C, with a duration between 1 and 48 hours.

The system of this invention that avoids the formation of explosive atmospheres in waterproof radioboyas, is can perform at room temperature, so it is not necessary the incorporation of any device to heat the system catalytic. Although, if desired, the bed can be heated catalytic at a higher temperature to increase the speed of reaction.

The process of this invention can be taken to place by placing the solid catalyst inside the buoy, or well forcing the passage of the gas present in the buoy through a catalyst bed located in a reactor.

Brief description of the figures

Figure 1: The object of the present invention can be better understood with the following description, in combination with the attached figure, which shows a generic example of assembly of a waterproof radio-buoy (1), with solar panels or other renewable energy source (2) that recharge batteries accumulators (4) and in which a container with certain amount of the catalyst object of the invention (5) to recombine the hydrogen generated by the batteries and avoid generation of flammable or explosive atmospheres.

Claims (19)

1. Hydrogen removal system inside sealed buoys (1), characterized in that it comprises at least the following elements:

to.

to the minus 1 solar panel or other renewable energy source (2);

b.

to the minus 1 rechargeable battery or accumulator (3);

C.

to the minus 1 electronic system (4); Y

d.

to the minus 1 solid catalyst (5).

2. Hydrogen removal system inside sealed buoys (1) according to claim 1, characterized in that the rechargeable battery (3) accumulates the energy obtained in the solar panel or other renewable energy source (2). 3. System for removing hydrogen from the inside of sealed buoys (1), according to claim 1, characterized in that the solid catalyst (5) is based on noble or seminoble metals on a specific high surface support and transition metals. 4. Hydrogen removal system inside sealed buoys (1), according to claims 1 and 3, characterized in that the noble or seminoble metals are selected and without limiting sense from the group consisting of palladium, platinum, silver, gold, rhodium, iridium, ruthenium, osmium or a combination thereof. 5. Hydrogen removal system inside sealed buoys (1), according to claims 1, 3 and 4, characterized in that the noble or seminoble metal is palladium or any combination thereof with any other metal. 6. System for removing hydrogen from the inside of sealed buoys (1), according to claims 1 and 3, characterized in that the transition metals are selected and without limitation from the group formed by iron, manganese, cobalt, nickel and chrome in form of rust 7. System for removing hydrogen from the inside of sealed buoys (1), according to claims 1 and 3, characterized in that the mass ratio between noble or seminoble metals and transition metals is 1: 100, preferably 5:25 . 8. System for removing hydrogen from the interior of sealed buoys (1), according to claims 1 and 3, characterized in that the specific high surface support is selected and without limiting sense from the group formed by high surface graphite, activated carbon, Carbon black, alumina, amorphous silica, structured silica, zirconium oxide, zeolites or zeotypes. 9. System for removing hydrogen from the inside of sealed buoys (1), according to claims 1 and 3, characterized in that the amount of noble or semi-noble metal that is in relation to the support is within the range from 0.001 to 10% by weight, preferably from 0.01 to 5% by weight. 10. Hydrogen removal system inside sealed buoys (1) according to claims 1 and 3, characterized in that the noble or semi-noble metal and transition metals are added to the support by impregnation, absorption or ion exchange. 11. System for removing hydrogen from the inside of sealed buoys (1), according to claims 1, 3 and 10, characterized in that the addition by impregnation is carried out with any salt soluble in the solvent used for the addition. 12. Procedure for removing hydrogen from the inside of sealed buoys (1), characterized in that the construction of the catalyst comprises the steps of:

to.

addition of noble metals or semi-noble to a high surface support specific;

b.

metal addition of transition;

C.

put on the catalyst in the presence of an inert gas;

d.

catalyst activation by heating; Y

and.

heat the catalyst until pretreatment temperature

13. Method according to claim 12, characterized in that the addition of noble or semi-noble metals and transition metals is carried out and without limitation by means of impregnation, absorption and ion exchange techniques. 14. Method according to claim 13, characterized in that the addition of noble or semi-noble metals and transition metals is carried out by impregnation with soluble salts of the group consisting of acetates, nitrates, halides and oxalates. 15. Method according to claim 12, characterized in that the inert gas is selected and without limitation from the group consisting of nitrogen, argon, carbon dioxide or in the presence of a gas containing oxygen or by treatment in an inert or oxidizing atmosphere. 16. Method according to claim 12, characterized in that the activation of the catalyst is carried out at temperatures within the range of 50 to 600 ° C and for a time interval of 1 to 48 hours. 17. Method according to claim 12, characterized in that the pretreatment of the catalyst is carried out at temperatures within the range of 200 to 1000 ° C for a time interval of 1 to 48 hours. 18. Method according to claim 12, characterized in that the catalytic reaction occurs at or near room temperature. 19. Use of the system to eliminate hydrogen inside watertight buoys (1) according to any of claims 1 to 11, to prevent the formation of atmospheres flammable or explosive