CA2157949A1 - Method for extinguishing a fire - Google Patents
Method for extinguishing a fireInfo
- Publication number
- CA2157949A1 CA2157949A1 CA002157949A CA2157949A CA2157949A1 CA 2157949 A1 CA2157949 A1 CA 2157949A1 CA 002157949 A CA002157949 A CA 002157949A CA 2157949 A CA2157949 A CA 2157949A CA 2157949 A1 CA2157949 A1 CA 2157949A1
- Authority
- CA
- Canada
- Prior art keywords
- gas
- area
- air
- extenguishing
- fire
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62C—FIRE-FIGHTING
- A62C99/00—Subject matter not provided for in other groups of this subclass
- A62C99/0009—Methods of extinguishing or preventing the spread of fire by cooling down or suffocating the flames
- A62C99/0018—Methods of extinguishing or preventing the spread of fire by cooling down or suffocating the flames using gases or vapours that do not support combustion, e.g. steam, carbon dioxide
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62C—FIRE-FIGHTING
- A62C35/00—Permanently-installed equipment
- A62C35/02—Permanently-installed equipment with containers for delivering the extinguishing substance
Landscapes
- Health & Medical Sciences (AREA)
- Public Health (AREA)
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Fire-Extinguishing By Fire Departments, And Fire-Extinguishing Equipment And Control Thereof (AREA)
Abstract
When extinguishing a fire by means of an extinguishing gas, after a fire is detected, the extinguishing gas is supplied under high pressure to the area in which the fire has broken out, with simultaneous displacement of air. In order to prevent gas speeds which are too high, the extinguishing gas is fed, in a first step, into a chamber which is delimited by a porous wall and subsequently, in a second step, is fed via the porous wall to the fire to be extinguished. Preferably, the displaced air is removed at a location which is related to the ratio of the specific weights of air and extinguishing gas.
Description
21~7949 Method for extinguishing a fire The invention relates to a method for extinguishing a fire by means of an extinguishing gas, wherein, after a fire is detected, the extinguishing gas is supplied under S pressure to the area in which the fire has broken out, with simultaneous displacement of alr.
A method of this type, which is disclosed in EP-A 0 496 066, is used in those cases where the use of fluid extinguishing agents is not possible or desirable, because of, for example, the damage to be anticipated as a consequence of the extinguishing fluid. Storage 10 areas for valuable articles such as works of art may be mentioned as an example of such cases. The use of fluid extinguishing agents can also not be considered in the case of electrical and electronic installations, and in the case of some installations in the chemical industry and the like.
The action of extinguishing gas is based either on the principle of a negative catalyst 15 or on the principle of displacement. In the former case, the extinguishing gas contains Halons. However, the use of Halons is no longer permitted under recent environmental legislation and, therefore, for as long as no replacement for Halons is available, use must be made of the displacement principle.
This latter principle is based on the fact that in virtually all cases the ambient air 20 must contain more than 15 % oxygen in order to be able to sustain a fire. Air usually contains 21 % oxygen; however, down to a concentration of 12 %, hllm~n~ and animals do not suffer from a lower oxygen concentration. On the basis of these data, extinguishing gas installations which are based on this principle are therefore designed in such a way that they are able, within a very short time, to introduce into the protected area an amount of 25 extinguishing gas such that the oxygen concentration in said area falls to a level of between 12 % and 15 %.
Using the displacement principle, a relatively large amount of extinguishing gas is needed to extinguish a fire. Although this amount is introduced into the protected area via several feed elements simultaneously, very high flow rates, which can even approach the 30 speed of sound, nevertheless occur when the gas flows in. With a high inflow of this type, troublesome side effects also arise, such as the entrainment of ambient air, as a result of which powerful air flows can be generated which have the character of a gale.
A further disadvantage of this known method, and in particular of the high inflow 21a7949 - speed associated with this method, lies in the extensive mixing which takes place between the air and the extinguishing gas. As a consequence of this, some of the extinguishing gas rapidly disappears from the protected area, as a result of which the displacement effect declines.
S Moreover, because of the high air speed, the fire can initially be fanned. This can also lead to dissemination of combustion products, burning materials, hazardous substances and/or infectious substances and the swirling-up of dust, which is particularly disadvantageous in the case of vulnerable articles, such as electronic equipment, works of art, and the like. An inflow of this type is associated with high noise levels, as a result of which communication becomes impossible and panic reactions may occur.
Roofs, walls, floors, windows and doors can also easily be overstressed by the large amounts of extinguishing gas. Furthermore, the displaced air must be prevented from passing on to adjacent areas, which makes the presence of extractors necessary.
Moreover, with the known method, condensation occurs on cold installation components which are in contact with the ambient air. This can be prevented by fitting thermal insulation. However, the outflow facilities cannot be covered, as a result of which condensation cannot be prevented in these areas.
In view of the fact that, with the known method, the extinguishing agent, which consists of a mixture of gas and liquid, is stored in the cryogenic state, the outflow speed must be fairly high in order to allow the extinguishing agent to extract heat from the environment to vaporise the fluid component. Consequently, an (undesirable) mixing of extinguishing agent and ambient air will always take place.
It is an object of the present invention to provide a novel method of ~Ali~uishing a fire which --il;g~to.s or obviates at least one of the above-described disadvantages of the 25 prior art.
Accolding to one aspect of the present invention, there is provided a method foreAli~uishing a fire by means of an ~,ALill~;uishing gas, wherein after a fire is detected, the ~Alinguishing gas is supplied under pl~;S~iUl~, to the area in which the fire has broken out, with cimlllt~nPous displ~rçment of air ch~r~ctçri7ed in that the ,Ali~uishing gas is 30 stored under a high plt;~i~Ule at ambient lelll~.~lult;, in a first step is fed to a chamber which is ~çlimit~l by a porous wall and subseql~çntly, in a second step, is fed via the porous wall to the fire to be ~,Ali~uished.
Feeding the eAli~uishing gas to the plole~;led area in the manner according to the -2157949 ~
invention has the advantage that, at a high extinguishing a gas fiow rate and a high feed plGS~UlG, the inflow rates remain restricted. The porous wall provides an inflow surface which is so large that it is no longer possible for high local speeds to arise. The noise production remains low. Moreover, the formation of con-len~tion is prevented.
A further advantage of feeding a large amount of t;Alinguishing gas at relatively low speed is the increased effectiveness thereof. This is because the low in~low speeds lead to little mixing of air and ~AIinguishing gas, as a result of which relatively little GAlh~uishing gas is removed from the area with the displaced air.
Preferably, the storage plGS~ulG is at least lO0 bar; the most pl~f~,llGd range of storage prGs~u.Gs is 150-250 bars.
In this context, the displaced air is preferably removed at a location which is related to the ratio of the specific weights of air and ~Alinguishing gas. Because there is only slight mixing, the ~,Ali~uishing gas can drive the air unil`o~llly in front of it. By now choosing the feed for ~ uishing gas and the discharge for displaced air in asuitable m~nn~.r, the desired GAlinguishing effect can a1ready be obtained with relatively little eAIhl~uishing gas since hardly any ~Ali l~uishing gas is lost through the discharge.
Also preferably, in this context an t;Ali l~uishing gas is used which has a specific weight higher than the specific weight of air and discharge of the displaced air takes place at a relatively high level.
Also preferably, an ~Alinguish gas is used which has a specific weight lower than the specific weight of air an discharge of the displaced air takes place at a relatively low level.
The present invention also relates to an area provided with an eA~ uishing in~t~ ti-)n for c~l~ing out the method described above, comprising storage means for a stock of GAlhlguishing gas under high pl~ si,u~ and, conn~ted to said stock, a feed element which opens into the area, as well as discharge means for removal of displaced air from said area.
Wlth this allangGIllent also, according to a first possibility, an GAlinguishing gas can be used which has a specific weight higher than the specific weight of air, and the discharge means for removal of the displaced air can be located at a relatively high level in the area.
Acconling to a second possibility, an ~Alhl~uishing gas can be used which has a specific weight lower than the specific weight of air, and the ~ çh~rge means for removal of the displaced air can be located at a relatively low level in the area.
Also preferably, the present invention includes a feed element for feeding extinguishing gas into an area as described above, comprising a chamber with an infla~v o~nillg for the ~ ;uishing gas, and a porous wall for relP~ing ~Alh~guishing gas from S the chamber.
Plt;se.,lly pl~ ed embo~liment~ of the present invention will now be described by way of exarnple only, with ,~f~,nce to the acco,llpal,~ g dla~ings, in which:Figure 1 shows a vertical cross-section through an area provided with an extinguishing gas in~t~ tion according to the invention; and, Figure 2 shows a cross-section through the feed elernent according to the invention.
The area 1 shown in Figure 1, in which an object, which is not in~ ted in more detail, to be protected against fire is located, is provided with two feed elements 2 accol~ g to the invention for ~Alu~guish gas. Said feed e~ nt~ are connt~t~ in a15 known manner via piping 3 and valve 4 to a holder 5. A large amount of extinguishing gas under high pressure is stored in said holder 5.
As soon as fire is detected in the area 1, for example via detection means which are known per se and are not shown, the valve 4 is opened, likewise in a known manner which is not shown, after which the extinguishing gas flows under high pressure and at high speed 20 to the feed elements 2.
As shown in Figure 2, said feed elements 2 comprise a chamber 6 surrounded by a porous, cylindrical wall 7. Said porous cylindrical wall can be made, for example, of sintered stainless steel. A wall 8 is located at one end of the chamber 6 and a wall 9, provided with a feed 10, is located at the other end. Upstream of said feed 10, there is a 25 restriction 11, which is adjustable in such a way that an identical flow rate can be obtained through both feed elements 2.
The extinguishing gas expands in the chamber 6, with a decrease in pressure and speed. The extinguishing gas then flows at a moderate speed into the area 1.
~la79~9 The ~,Alinguishing gas fed under high plGS~iUl~ ~Yp~n~ls in chamber 6, as a result of which the rate of flow decreases. The ~;Alillguishing gas then flows at moderate speed via porous wall 7 into the area to be protected. An advantage is that the drop in ~lllp~l~lule which occurs during Pxr~nsion remains relatively slight, with the result that there is no ice formation. Only a layer of rime is deposited, which sublimes without dli~)ping phellolllena, such as would occur on the lLa~ing of ice deposits.
Preferably, the inflow opening has an adjustable restriction for controlling theflow rate of the ~,Alinguishing gas. On feeding the t;Alillguishing gas via elements, the restrictions can in each case be so adjusted that a feed of t;Ali,l~;uishing gas unir~llllly distributed over all elements takes place.
According to the presently pl~rel-ed embodiment, the porous wall 7 is cylindrical and closed at one end by an end baffle, whilst it has an end baffle co"~zlining an inflow Opellillg at the opposing end.
FullL~llllore, the porous wall 7 is preferably made of sintered st~in1ess steel. A
m~tPri~1 of this type is well able to resist corrosion; there is then also hardly an risk of blocking, even during the prolonged period in which the inst~ tion has to remain ready for use. Moreover this m~tPri~1 can be subjected to mechanical stress without any problems. A further advantage is the predictable and readily reproducible porosity.
However, other sintered materials, such as sintered bronze, can also be used. Itis also conceivable to use ceramic m~teri~1s, on condition that the mech~nir~1 stresses allow this.
The feed e1emPnt can also have two sep~dle inflow openillgs, each with its own restriction. The twin feed not only offers the possibility of mixing different eAling.lishing gases and so feeding these simu1~nPously, but also makes it possible to inject water into the eAlinguishing gas. ~?rlz~inil1~ the low-pulse feed, the atomised water will rapidly vaporise and eYp~n-l. As a concequ~nre of this, not only will the air be displaced rapidly but, at the same time, as a consequence of the vaporisation of the water, heat will also be withdrawn from the environment and the object to be ~Al~uished.
The feed elements 2 of the porous m~teri~1 is also suitable for low-pulse atomisation of a liquefied gas, such as carbon ~lioxi~le, which leads to a much more effective oxygen displacement and cooling. This latter application is also suitable as water-saving cooling in production processes.
A further advantage is that, despite the low temperature of the feed element, no -2157~49 6 contlen~ti-)n of water vapour on feed element 2 takes place bec~lse, during feeding of the ~Alinguishing gas, the feed element is completely ~ulloullded by t;AIill~uishing gas in which virtually no water vapour is present. Ambient air can come into contact with the feed elemPnt only after the feed of extinguishing gas has ceased. As a result of the feed 5 of dry t;AIinguishing gas, the moisture content of the ambient air is ap~l~iably lower than before. A thin layer of rime forms on the feed e1Pment and sublimes withoutrol.ning drips.
A feed e4m-Pnt 2 made of shlle~ed m~tPri~l has been used previously and has beendescribed in EP-A 0 496 066. However, in this case the feed elemPnt serves only for 10 very fine dispersion of the nliAIul~ of liquid and gaseous eAli~g~lishing gas (argon stored under clyu~;~nic conditions; p~cs~ ; 15 to 40 bar) in order to promote rapid vaporisation of the liquid argon. However, the outflow speeds reached with this ~..d~lgP..~ent are ap~l~cLably higher than those accolding to the invention and indeed must be so in order to be able to achieve the target rapid vaporisation. The described advantages of the low 15 outflaw speeds (with respect to restriction of mixing with ambient air and con-len~tion) are not achieved with the known feed ç1Pm~nt In the illustrative embodiment shown, the extinguishing gas has a specific weight which is higher than the specific weight of the air initially present in the area 1. As, moreover, the extinguishing gas flows in at a moderate speed, as a result of which there 20 is hardly any mixing with the air, the extinguishing gas will initially collect at a low level 12 in the area 1. The extinguishing gas front 13 drives the air present in the area 1 before it, in such a way that the air can flow away uniformly through the discharge outlets 14 provided in the area 1. The air flow is indicated by the arrows 15.
The dis~harge outlets in the area can be provided with a seal which is breakable25 under the effect of overpressure in the area, for example a breakable membrane. A seal of this type prevents any outside influences, for example, the effects of weather, from being able to reach the protected area during normal operations.
A possible embodiment of the discharge facility comprises a weight-loaded overpressure valve with a breakable membrane, for example made of plastic film, on both 30 the inlet side and the outlet side. When a set overpressure is exceeded, the membranes are broken. The excess air can then escape to the outside via the overpressure valve, the pressure thus being kept substantially equal to the atmospheric pressure. When the feed of extinguishing gas ceases, the non-return valve closes to a sufficient extent to prevent the . 21579g9 escape of extinguishing gas to the outside and the ingress of oxygen-rich air. As long as the membranes have not been broken, they provide good thermal insulation and a good vapour-tight and dust-tight seal.
The advantage of this method is that hardly any extinguishing gas is lost through the S discharge outlets 14, such that an extinguishing effect can be achieved with minimum amounts of extinguishing gas. A further advantage is that high flow speeds hardly occur in the area 1, as a result of which the objects located in said area remain spared and hardly any dissemination of hazardous or infectious substances will occur.
The present invention has been described with lt;r~ "ee to a presently pl~rtil~d10 embodiment. Other va~iations and embo-lim~ntc of the present invention may be a~a~t;nl to those of olJi~ y skill in the art. Accor~lingly, the scope of protection sought for the present invention is only limited as set out in the attached claims.
A method of this type, which is disclosed in EP-A 0 496 066, is used in those cases where the use of fluid extinguishing agents is not possible or desirable, because of, for example, the damage to be anticipated as a consequence of the extinguishing fluid. Storage 10 areas for valuable articles such as works of art may be mentioned as an example of such cases. The use of fluid extinguishing agents can also not be considered in the case of electrical and electronic installations, and in the case of some installations in the chemical industry and the like.
The action of extinguishing gas is based either on the principle of a negative catalyst 15 or on the principle of displacement. In the former case, the extinguishing gas contains Halons. However, the use of Halons is no longer permitted under recent environmental legislation and, therefore, for as long as no replacement for Halons is available, use must be made of the displacement principle.
This latter principle is based on the fact that in virtually all cases the ambient air 20 must contain more than 15 % oxygen in order to be able to sustain a fire. Air usually contains 21 % oxygen; however, down to a concentration of 12 %, hllm~n~ and animals do not suffer from a lower oxygen concentration. On the basis of these data, extinguishing gas installations which are based on this principle are therefore designed in such a way that they are able, within a very short time, to introduce into the protected area an amount of 25 extinguishing gas such that the oxygen concentration in said area falls to a level of between 12 % and 15 %.
Using the displacement principle, a relatively large amount of extinguishing gas is needed to extinguish a fire. Although this amount is introduced into the protected area via several feed elements simultaneously, very high flow rates, which can even approach the 30 speed of sound, nevertheless occur when the gas flows in. With a high inflow of this type, troublesome side effects also arise, such as the entrainment of ambient air, as a result of which powerful air flows can be generated which have the character of a gale.
A further disadvantage of this known method, and in particular of the high inflow 21a7949 - speed associated with this method, lies in the extensive mixing which takes place between the air and the extinguishing gas. As a consequence of this, some of the extinguishing gas rapidly disappears from the protected area, as a result of which the displacement effect declines.
S Moreover, because of the high air speed, the fire can initially be fanned. This can also lead to dissemination of combustion products, burning materials, hazardous substances and/or infectious substances and the swirling-up of dust, which is particularly disadvantageous in the case of vulnerable articles, such as electronic equipment, works of art, and the like. An inflow of this type is associated with high noise levels, as a result of which communication becomes impossible and panic reactions may occur.
Roofs, walls, floors, windows and doors can also easily be overstressed by the large amounts of extinguishing gas. Furthermore, the displaced air must be prevented from passing on to adjacent areas, which makes the presence of extractors necessary.
Moreover, with the known method, condensation occurs on cold installation components which are in contact with the ambient air. This can be prevented by fitting thermal insulation. However, the outflow facilities cannot be covered, as a result of which condensation cannot be prevented in these areas.
In view of the fact that, with the known method, the extinguishing agent, which consists of a mixture of gas and liquid, is stored in the cryogenic state, the outflow speed must be fairly high in order to allow the extinguishing agent to extract heat from the environment to vaporise the fluid component. Consequently, an (undesirable) mixing of extinguishing agent and ambient air will always take place.
It is an object of the present invention to provide a novel method of ~Ali~uishing a fire which --il;g~to.s or obviates at least one of the above-described disadvantages of the 25 prior art.
Accolding to one aspect of the present invention, there is provided a method foreAli~uishing a fire by means of an ~,ALill~;uishing gas, wherein after a fire is detected, the ~Alinguishing gas is supplied under pl~;S~iUl~, to the area in which the fire has broken out, with cimlllt~nPous displ~rçment of air ch~r~ctçri7ed in that the ,Ali~uishing gas is 30 stored under a high plt;~i~Ule at ambient lelll~.~lult;, in a first step is fed to a chamber which is ~çlimit~l by a porous wall and subseql~çntly, in a second step, is fed via the porous wall to the fire to be ~,Ali~uished.
Feeding the eAli~uishing gas to the plole~;led area in the manner according to the -2157949 ~
invention has the advantage that, at a high extinguishing a gas fiow rate and a high feed plGS~UlG, the inflow rates remain restricted. The porous wall provides an inflow surface which is so large that it is no longer possible for high local speeds to arise. The noise production remains low. Moreover, the formation of con-len~tion is prevented.
A further advantage of feeding a large amount of t;Alinguishing gas at relatively low speed is the increased effectiveness thereof. This is because the low in~low speeds lead to little mixing of air and ~AIinguishing gas, as a result of which relatively little GAlh~uishing gas is removed from the area with the displaced air.
Preferably, the storage plGS~ulG is at least lO0 bar; the most pl~f~,llGd range of storage prGs~u.Gs is 150-250 bars.
In this context, the displaced air is preferably removed at a location which is related to the ratio of the specific weights of air and ~Alinguishing gas. Because there is only slight mixing, the ~,Ali~uishing gas can drive the air unil`o~llly in front of it. By now choosing the feed for ~ uishing gas and the discharge for displaced air in asuitable m~nn~.r, the desired GAlinguishing effect can a1ready be obtained with relatively little eAIhl~uishing gas since hardly any ~Ali l~uishing gas is lost through the discharge.
Also preferably, in this context an t;Ali l~uishing gas is used which has a specific weight higher than the specific weight of air and discharge of the displaced air takes place at a relatively high level.
Also preferably, an ~Alinguish gas is used which has a specific weight lower than the specific weight of air an discharge of the displaced air takes place at a relatively low level.
The present invention also relates to an area provided with an eA~ uishing in~t~ ti-)n for c~l~ing out the method described above, comprising storage means for a stock of GAlhlguishing gas under high pl~ si,u~ and, conn~ted to said stock, a feed element which opens into the area, as well as discharge means for removal of displaced air from said area.
Wlth this allangGIllent also, according to a first possibility, an GAlinguishing gas can be used which has a specific weight higher than the specific weight of air, and the discharge means for removal of the displaced air can be located at a relatively high level in the area.
Acconling to a second possibility, an ~Alhl~uishing gas can be used which has a specific weight lower than the specific weight of air, and the ~ çh~rge means for removal of the displaced air can be located at a relatively low level in the area.
Also preferably, the present invention includes a feed element for feeding extinguishing gas into an area as described above, comprising a chamber with an infla~v o~nillg for the ~ ;uishing gas, and a porous wall for relP~ing ~Alh~guishing gas from S the chamber.
Plt;se.,lly pl~ ed embo~liment~ of the present invention will now be described by way of exarnple only, with ,~f~,nce to the acco,llpal,~ g dla~ings, in which:Figure 1 shows a vertical cross-section through an area provided with an extinguishing gas in~t~ tion according to the invention; and, Figure 2 shows a cross-section through the feed elernent according to the invention.
The area 1 shown in Figure 1, in which an object, which is not in~ ted in more detail, to be protected against fire is located, is provided with two feed elements 2 accol~ g to the invention for ~Alu~guish gas. Said feed e~ nt~ are connt~t~ in a15 known manner via piping 3 and valve 4 to a holder 5. A large amount of extinguishing gas under high pressure is stored in said holder 5.
As soon as fire is detected in the area 1, for example via detection means which are known per se and are not shown, the valve 4 is opened, likewise in a known manner which is not shown, after which the extinguishing gas flows under high pressure and at high speed 20 to the feed elements 2.
As shown in Figure 2, said feed elements 2 comprise a chamber 6 surrounded by a porous, cylindrical wall 7. Said porous cylindrical wall can be made, for example, of sintered stainless steel. A wall 8 is located at one end of the chamber 6 and a wall 9, provided with a feed 10, is located at the other end. Upstream of said feed 10, there is a 25 restriction 11, which is adjustable in such a way that an identical flow rate can be obtained through both feed elements 2.
The extinguishing gas expands in the chamber 6, with a decrease in pressure and speed. The extinguishing gas then flows at a moderate speed into the area 1.
~la79~9 The ~,Alinguishing gas fed under high plGS~iUl~ ~Yp~n~ls in chamber 6, as a result of which the rate of flow decreases. The ~;Alillguishing gas then flows at moderate speed via porous wall 7 into the area to be protected. An advantage is that the drop in ~lllp~l~lule which occurs during Pxr~nsion remains relatively slight, with the result that there is no ice formation. Only a layer of rime is deposited, which sublimes without dli~)ping phellolllena, such as would occur on the lLa~ing of ice deposits.
Preferably, the inflow opening has an adjustable restriction for controlling theflow rate of the ~,Alinguishing gas. On feeding the t;Alillguishing gas via elements, the restrictions can in each case be so adjusted that a feed of t;Ali,l~;uishing gas unir~llllly distributed over all elements takes place.
According to the presently pl~rel-ed embodiment, the porous wall 7 is cylindrical and closed at one end by an end baffle, whilst it has an end baffle co"~zlining an inflow Opellillg at the opposing end.
FullL~llllore, the porous wall 7 is preferably made of sintered st~in1ess steel. A
m~tPri~1 of this type is well able to resist corrosion; there is then also hardly an risk of blocking, even during the prolonged period in which the inst~ tion has to remain ready for use. Moreover this m~tPri~1 can be subjected to mechanical stress without any problems. A further advantage is the predictable and readily reproducible porosity.
However, other sintered materials, such as sintered bronze, can also be used. Itis also conceivable to use ceramic m~teri~1s, on condition that the mech~nir~1 stresses allow this.
The feed e1emPnt can also have two sep~dle inflow openillgs, each with its own restriction. The twin feed not only offers the possibility of mixing different eAling.lishing gases and so feeding these simu1~nPously, but also makes it possible to inject water into the eAlinguishing gas. ~?rlz~inil1~ the low-pulse feed, the atomised water will rapidly vaporise and eYp~n-l. As a concequ~nre of this, not only will the air be displaced rapidly but, at the same time, as a consequence of the vaporisation of the water, heat will also be withdrawn from the environment and the object to be ~Al~uished.
The feed elements 2 of the porous m~teri~1 is also suitable for low-pulse atomisation of a liquefied gas, such as carbon ~lioxi~le, which leads to a much more effective oxygen displacement and cooling. This latter application is also suitable as water-saving cooling in production processes.
A further advantage is that, despite the low temperature of the feed element, no -2157~49 6 contlen~ti-)n of water vapour on feed element 2 takes place bec~lse, during feeding of the ~Alinguishing gas, the feed element is completely ~ulloullded by t;AIill~uishing gas in which virtually no water vapour is present. Ambient air can come into contact with the feed elemPnt only after the feed of extinguishing gas has ceased. As a result of the feed 5 of dry t;AIinguishing gas, the moisture content of the ambient air is ap~l~iably lower than before. A thin layer of rime forms on the feed e1Pment and sublimes withoutrol.ning drips.
A feed e4m-Pnt 2 made of shlle~ed m~tPri~l has been used previously and has beendescribed in EP-A 0 496 066. However, in this case the feed elemPnt serves only for 10 very fine dispersion of the nliAIul~ of liquid and gaseous eAli~g~lishing gas (argon stored under clyu~;~nic conditions; p~cs~ ; 15 to 40 bar) in order to promote rapid vaporisation of the liquid argon. However, the outflow speeds reached with this ~..d~lgP..~ent are ap~l~cLably higher than those accolding to the invention and indeed must be so in order to be able to achieve the target rapid vaporisation. The described advantages of the low 15 outflaw speeds (with respect to restriction of mixing with ambient air and con-len~tion) are not achieved with the known feed ç1Pm~nt In the illustrative embodiment shown, the extinguishing gas has a specific weight which is higher than the specific weight of the air initially present in the area 1. As, moreover, the extinguishing gas flows in at a moderate speed, as a result of which there 20 is hardly any mixing with the air, the extinguishing gas will initially collect at a low level 12 in the area 1. The extinguishing gas front 13 drives the air present in the area 1 before it, in such a way that the air can flow away uniformly through the discharge outlets 14 provided in the area 1. The air flow is indicated by the arrows 15.
The dis~harge outlets in the area can be provided with a seal which is breakable25 under the effect of overpressure in the area, for example a breakable membrane. A seal of this type prevents any outside influences, for example, the effects of weather, from being able to reach the protected area during normal operations.
A possible embodiment of the discharge facility comprises a weight-loaded overpressure valve with a breakable membrane, for example made of plastic film, on both 30 the inlet side and the outlet side. When a set overpressure is exceeded, the membranes are broken. The excess air can then escape to the outside via the overpressure valve, the pressure thus being kept substantially equal to the atmospheric pressure. When the feed of extinguishing gas ceases, the non-return valve closes to a sufficient extent to prevent the . 21579g9 escape of extinguishing gas to the outside and the ingress of oxygen-rich air. As long as the membranes have not been broken, they provide good thermal insulation and a good vapour-tight and dust-tight seal.
The advantage of this method is that hardly any extinguishing gas is lost through the S discharge outlets 14, such that an extinguishing effect can be achieved with minimum amounts of extinguishing gas. A further advantage is that high flow speeds hardly occur in the area 1, as a result of which the objects located in said area remain spared and hardly any dissemination of hazardous or infectious substances will occur.
The present invention has been described with lt;r~ "ee to a presently pl~rtil~d10 embodiment. Other va~iations and embo-lim~ntc of the present invention may be a~a~t;nl to those of olJi~ y skill in the art. Accor~lingly, the scope of protection sought for the present invention is only limited as set out in the attached claims.
Claims (17)
1. Method for extinguishing a fire by means of an extenguishing gas, wherein, after a fire is detected, the extinguishing gas is supplied under pressure to the area in which the fire has broken out, with simultaneous displacement of air, characterised in that the extinguishing gas is stored under a high pressure at ambient temperature, in a first step is fed to a chamber which is delimited by a porous wall and subsequently, in a second step, is fed via the porous wall to the fire to be extenguished.
2. Method according to Claim 1, wherein the storage pressure is a least 100 bar.
3. Method according to Claim 1 or 2, wherein the storage pressure is between 150 bar and 250 bar.
4. Method according to Claim 1 or 2, wherein the displaced air is removed at a location which is related to the ratio of the specific weights of air and extenguishing gas.
5. Method according to Claim 4, wherein an extenguishing gas is used which has aspecific weight higher than the specific weight of air and discharge of the displaced air takes place at a relatively high level.
6. Method according to Claim 4, wherein an extinguishing gas is used which has aspecific weight lower than the specific weight of air and discharge of the displaced air takes place at a relatively low level.
7. An area provided with an extenguishing installation for carrying out the method according to Claim 1, comprising storage means for storing a stock of extinguishing gas under high pressure and, connected to said stock, a feed element which opens into the area, as well as a discharge means for removal of displaced air from said area.
8. The area according to Claim 7, wherein the extenguishing gas used has a specific weight higher than the specific weight of air, and the discharge means for removal of the displaced air are located at a relatively high level in the area.
9. The area according to Claim 7, wherein the extenguishing gas used has a specific weight lower than the specific weight of air, and the discharge means for removal of the displaced air are located at a relatively low level in the area.
10. The area according to Claim 7, 8, or 9, wherein each discharge outlet is provided with a seal which is breakable under the effect of overpressure in the area.
11. Area according to Claim 10, wherein the seal comprises at least one breakable membrane.
12. A feed element for feeding the extenguishing as into an area according to one of Claims 7, 8, 9 or 11 comprising a chamber with an inilow opening for the extenguishing gas, and a porous wall for releasing extenguishing gas from the chamber.
13. The feed element according to Claim 12, wherein the inflow opening has an adjustable restriction for controlling the flow rate of the extenguishing gas.
14. The feed element according to Claim 13, wherein the porous wall is cylindrical and closed at one end by an end baffle, and has an end baffle containing the inflow opening at the opposing end.
15. The feed element according to Claim 14, wherein the inflow opening has an adjustable restriction.
16. The feed element according to one of Claims 13, 14 or 15, wherein the porous wall is made of sintered stainless steel.
17. The feed element according to one of Claims 13, 14 or 15, wherein two separate inflow opening are provided, each with its own restriction.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL9401480A NL9401480A (en) | 1994-09-09 | 1994-09-09 | Method for extinguishing a fire. |
| NL9401480 | 1994-09-09 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2157949A1 true CA2157949A1 (en) | 1996-03-10 |
Family
ID=19864643
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002157949A Abandoned CA2157949A1 (en) | 1994-09-09 | 1995-09-11 | Method for extinguishing a fire |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0700693A1 (en) |
| CA (1) | CA2157949A1 (en) |
| NL (1) | NL9401480A (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001033983A (en) * | 1999-07-15 | 2001-02-09 | Mitsubishi Electric Corp | Pattern forming method, production of semiconductor device using same, and semiconductor device |
| IT1317475B1 (en) * | 2000-05-05 | 2003-07-09 | Vesta S R L | NOZZLE SILENCED FOR THE DISCHARGE OF EXTINGUISHING GASES. |
| AU2002221560B2 (en) * | 2001-01-11 | 2006-09-14 | Wagner Group Gmbh | Inert rendering method with a nitrogen buffer |
| US20080078563A1 (en) * | 2006-10-02 | 2008-04-03 | Ansul, Inc. | Oxygen absorbing fire suppression system |
| JP4988945B2 (en) * | 2009-10-23 | 2012-08-01 | エア・ウォーター防災株式会社 | Gas fire extinguishing equipment |
| JP5972518B2 (en) * | 2009-11-02 | 2016-08-17 | 株式会社コーアツ | Ejection head with a sound deadening function for gas fire extinguishing equipment |
| JP7141075B2 (en) * | 2016-04-14 | 2022-09-22 | 株式会社コーアツ | Low wind velocity gas fire extinguishing system |
| CN115671641B (en) * | 2022-10-27 | 2023-10-20 | 国网浙江省电力有限公司湖州供电公司 | High-vaporization heat porous fire extinguishing medium applied to electrochemical energy storage system and preparation method thereof |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2713391A (en) * | 1951-09-11 | 1955-07-19 | American La France Foamite | Pyrotechnic-operated fire extinguisher |
| US3486562A (en) * | 1968-03-08 | 1969-12-30 | David K Goodloe | Fire prevention,detection and extinguishing system |
| US3893514A (en) * | 1973-11-23 | 1975-07-08 | Us Navy | Suppression of fires in confined spaces by pressurization |
| DE4101668A1 (en) * | 1991-01-22 | 1992-07-23 | Messer Griesheim Gmbh | FIRE EXTINGUISHING DEVICE WITH A STORAGE FOR A LOW-BOILED GAS LIQUIDED |
| DK185691D0 (en) * | 1991-11-12 | 1991-11-12 | Torbjoern Gerner Laursen | METHOD OF EXTINGUISHING OR PREVENTING FIRE |
-
1994
- 1994-09-09 NL NL9401480A patent/NL9401480A/en active Search and Examination
-
1995
- 1995-09-07 EP EP95202438A patent/EP0700693A1/en not_active Withdrawn
- 1995-09-11 CA CA002157949A patent/CA2157949A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| NL9401480A (en) | 1996-04-01 |
| EP0700693A1 (en) | 1996-03-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CZ64995A3 (en) | Fire extinguishing apparatus and fire extinguishing method | |
| US7921927B2 (en) | Gaseous and liquid agent fire suppression system using emitters with closed end cavity deflector | |
| RU2469759C2 (en) | Inerting method used to reduce inflammation hazard in closed space, and device for implementation of that method | |
| KR101373639B1 (en) | Method and device for the regulated feed of supply air | |
| Kim et al. | Extinction limit of a pool fire with a water mist | |
| US4800961A (en) | Sprinkler or fire-extinguishing nozzle | |
| CA2157949A1 (en) | Method for extinguishing a fire | |
| US5197548A (en) | Fire extinguishing device with storage tank for a low-boiling liquefied gas which serves as extinguishing agent | |
| US4872513A (en) | Chimney fire extinguisher | |
| WO2007125070A2 (en) | Extinguishing substance, method and system for the utilization thereof | |
| JP2008526409A (en) | Deactivation method for fire prevention | |
| CN109999394A (en) | A kind of nitrogen automatic fire prevention fire extinguishing system | |
| RU2752438C1 (en) | Nitrogen fire extinguishing system for special structure | |
| Log et al. | ‘Water mist’for fire protection of historic buildings and museums | |
| US6036118A (en) | Liquid delivery nozzle | |
| FI96174B (en) | The spray head | |
| RU2108828C1 (en) | Automatic plant for gas fire extinguishing | |
| DK2322251T3 (en) | A method of operating a fire-extinguishing system | |
| KR101034564B1 (en) | An automatic fire extinguishing equipment using gas hydrate | |
| RU2053822C1 (en) | Aerosol fire fighting plant | |
| US6923265B2 (en) | Submerged thermally sensitive element for an automatic fire sprinkler | |
| Na’inna et al. | FIRE SAFETY DESIGN OF A 5 STOREY OFFICE BUILDING: FIRE SUPPRESSION | |
| Goodall et al. | Inert Gas Extinguishing Systems: Constant Discharge Flow Rate vs. Decaying Flow Rate. | |
| AU689118B2 (en) | Fire extinguishing apparatus & method | |
| Kim et al. | Water Mist Fire Suppression for Raised Subfloor Spaces |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued | ||
| FZDE | Discontinued |
Effective date: 19980911 |