DE2749050A1 - Blowdown device for steam in reactor primary circuit rupture - having conical baffle inside and conical skirt outside the immersed pipe end - Google Patents

Abstract

The device is for mixing a gas or gaseous mixt. with a liq. medium and is intended esp. for the blow down steam produced in the maximum credible accident of a nuclear reactor. The blowdown pipe has an open bottom end discharging below the water surface; concentrically mounted in the open end of th pipe is a conical block or baffle, its apex pointing up into the pipe opening and its base horizontally below th pipe opening to form an annular space inside the pipe and round the cone. Outside and concentric to the pipe a truncated conical plate surrounds the lower region of the pipe with its upper, smaller end and extends down below the bottom of the pipe with its wider, lower end, which thus also surrounds the base of the conical block. The steam blowdown from the pipe draws in water through the annular gap outside the pipe end and inside the truncated conical skirt. The effect of this is to produce a very large number of small steam or gas bubbles.

Description

description

Device for mixing gases and liquids The invention relates to a device for mixing a gaseous medium with a liquid one Medium, in particular a mixing and distribution device for use in nuclear reactors to improve the mastery of heat and pressure energy generated by one Reactor accident results.

Nuclear power plants, which act as pressurized water or boiling water reactors are formed, are generally enclosed with a chamber that of the receptacle of escaping steam and which should withstand the maximum possible pressure, which can arise in the event of an accident in the nuclear reactor. Such accidents can can be traced back to a break in a coolant line or in the reactor vessel, which lead to sudden evaporation of the water used as the coolant. Furthermore, there is the possibility of that due to chemical reactions between the core material and the metal cladding on the one hand and the strongly heated water on the other gaseous hydrogen is released. It is essential that these gases and Earth vapors in the reactor and so that the pressure is reduced so that that it does not exceed the structural strength of the pressure collector. The materials present in some fuels and those after a radioactive Irradiation in all nuclear fuels is for animal use and / or plant life harmful. The release of such substances into the Environment in the event of a serious reactor accident must therefore be prevented.

The worst conceivable reactor accident is generally a rupture of the reactor pressure vessel or of a main coolant line connected to it, when associated with exothermic chemical reactions between nuclear fuels and the coolant, moderator, or other matter that is present could be. The energy released in such an accident can be quite high and depends in part on the iblenge and the maximum temperature of the coolant away. In such an accident, considerable amounts of steam are formed, some of which are gaseous Contain fission products such as lialogene and radioactive gases. The security of Nuclear power plants is based on the principle that in the event of an accident involving the Release of radioactive fission products, all contaminated gases, Liquids and solids collected in a tight container or container system until the level of radioactivity has decreased significantly.

In large power plants it is difficult to operate under high pressure; to collect standing gas completely so that it is partially destroyed Need to become. The best known solution to this problem is to go around to provide a container for the actual Iernreaktor and the primary cooling system, which has a sufficient volume, ur ..

the evaporating coolant in the event of a line break or the like to be caught with moderate pressure. It is known to have a toroidal or annular Provide pressure chamber, which is about half filled with water and which is connected to the reactor system so that excess steam in the water supply is condensed in the pressure vessel.

These one-piece ring-shaped pressure vessels are very large tanks, for example with a diameter of about 10 m in cross section and with a Diameter of its ring-shaped central axis of about 35 m. The ring-shaped pressure vessel is arranged in an opening or fuse chamber, which has a drying room of the reactor system and which with this drying room over a number of Relief channels are connected, each consisting of a pressure line and assemble a standpipe. Other pressure vessels of the known type exist from several spherical pressure tanks, which are connected to the drying room via overpressure lines and standpipes are connected. A large, closed one has already been used as a pressure chamber Proposed chamber below the actual reactor.

In all previously known pressure chamber arrangements, the steam and other substance released in a reactor accident via overpressure lines and standpipes introduced into the Druckka.ern, with the standpipes below the surface of the water end in the Druckkarmer or the Druckkaiflern. The water is in the Pressure chambers to condense the steam and cool it down, so that the internal pressure in which: ufanabe! does not older the structurally specified load capacity of the same exceeds.

Furthermore, nuclear reactor systems usually contain pressure relief valves, which serve, in the event of a rapid pressure increase, to the one below an excessive one Blow off steam under pressure from the coolant lines. Typically own the pressure relief valves blow-off lines that open into the or one of the pressure chambers, so that the steam is quickly condensed. These pressure relief valves must be at least checked once a year to ensure that they are working properly.

In a typical nuclear reactor, the dry room containment 3 container have a volume of up to 750 square meters. In the event of an accident, this container will now be used a considerable amount of air and steam through the positive pressure lines and standpipes pressed into the pressure vessel. This large air-steam volume is combined with The air that was previously in the pipelines suddenly becomes deep below the water surface, possibly directly at the bottom of the pressure chamber, in the water supply initiated, where an air bubble quickly forms, which is what is above Raises water and compresses the air above the water surface in the pressure chamber. It was calculated that with an annular pressure chamber the water with. one Hit the top of the annular chamber at a speed of more than 8m / sec could be likely to damage bellows and other equipment would result in the upper part of the annular pressure chamber. Furthermore, the inertial force would this massive amount of water when it hits the upper part of the pressure chamber drive to a shift or movement of the same, which can cause damage, which is expected to Occurrence of leaks and release of radioactive substances.

In common coal-fired power plants, as in nuclear power plants Overpressure valves required, over which at a rapid pressure increase under high Steam under pressure can be blown off. The collection and distribution of the Noise and the heat energy released when such a pressure relief valve is activated is also desirable. In addition, it is at various industrial Method desirable, rapid and effective mixing of a gaseous medium to be achieved with a liquid medium.

The invention is based on the prior art, the task based on a mixing and distribution device to specify which the energy becomes free in the event of a reactor accident or when a steam pressure relief valve is triggered, distribute and annihilate: ann and which, in addition, basically for one industrial use for fast and effective mixing of gaseous media and liquid media is suitable.

This task is achieved by a mixing device as described at the outset rt solved, which is characterized according to the invention by the following features: (a) A hollow conduit is provided which has an open land through it that a gaseous medium is expelled and that is immersed in a liquid; (b) a conical impact member is provided, which has an inclined wall, which extends from a circular disc-shaped base to a tip, which is disposed adjacent the open lower end of the conduit; (c) it is a hollow annular skirt is provided which has an inclined wall extending from an upper opening extends to a lower opening, the upper opening being smaller is called the lower opening and wherein the upper opening is adjacent to the conduit surrounding the lower end thereof and so an annular opening between the conduit and bounded by the upper opening and wherein the lower opening is the open lower End of the conduit facing away and surrounding the base of the conical baffle member; so that the gaseous medium, which is expelled from the line, with the liquid Medium is mixed, which is sucked in through the annular opening, whereby the gaseous medium at the lower opening of the apron in the form of numerous smaller ones Gas bubbles emerge.

The invention is particularly advantageous in the case of nuclear power plants. Such power plants have a safety reactor, which is surrounded by a container is, which encloses a drying room. The actual reactor is from surrounded by a water circuit, the water being heated by the reactor. In addition, at least one pressure chamber is provided, into which an overpressure line, the one with the drying room is in connection, reaches into, where their lower end under the surface of the water in the at least one drying chamber reaches down. If now on this pipe immersed in the water of the pressure chamber, a mixing and distributing device according to the invention is provided, then Air and steam as well as radioactive substances released in an accident by the Pipe are pressed, mixed with the water passing through the annular Opening is sucked in, with steam, air and radioactive substances in the pressure chamber are distributed and wherein the steam is condensed.

A decisive advantage of the mixing and distributing device according to the invention therefore consists in the fact that this is used for this purpose in large-scale power plants the energy generated in an accident or when a Overpressure valve to absorb energy released in the pressure vessel and so in to pass on the water it contains, damage and breakdowns be avoided.

Another advantage of the device according to the invention is that that it is suitable for the rapid and effective addition of gaseous and liquid media Mix.

Further details and advantages of the invention are given below explained in more detail with reference to drawings andZor are the subject of claims for protection. The figures show: FIG. 1 a schematic longitudinal section through a nuclear power plant, at which a preferred .Rustührlngs, or .t of the invention is realized; Fig. 2 a horizontal cross section through the nuclear power plant according to FIG. 1, seen from line 2-2 in this figure; 3 shows a longitudinal section through a modified one Type of power plant with devices according to the invention ;.

4 shows a perspective illustration of essential parts of a third Type of power plant with devices according to the invention; Fig. 5 is a vertical section through one of the spherical pressure vessels of the power plant according to FIG. 4 and FIG. 6 shows a side view of a preferred embodiment of a mixing and distributing device according to the invention, with some parts broken away for clarity.

Figs. 1 and 2 show a conventional power plant 10 with a multi-story Building 12 usual construction, which has a roof 14, walls 16, a room 18 for the Fuel pick-up, a crane 20, a control room 22 and others not detailed has designated rooms required for the operation of the power plant. By doing Building 12 is a nuclear reactor boiler 24, in which a nuclear reactor (not specially shown) is located. The boiler 24 is partially covered by a protective shield 26 surrounded. In addition, the boiler 24 is completely one pear-shaped Surrounding chamber 28 in which a drying room 30 is located. The chamber 28 is in essentially surrounded by a concrete base 32, which is also the foundation for the building 12 forms. Upper pressure pipes 36 are provided at the bottom of the chamber 28, which on the one hand are connected to the drying room 30 via openings 34 and on the other hand pass through the wall of a toroidal pressure chamber 38, which is partially filled with water 40. The overpressure tubes 36 terminate in a Ring line 42 in the pressure chamber 38. Standpipes extend from the ring line 42 to below the surface of the water. This results in a continuous overpressure channel from the drying room 30 via the upper pressure pipes 36, the ring line 40 and the standpipes 44. Finally, at the lower end of each standpipe 44, there is a distributor head 46 according to FIG the invention provided.

Coolant lines extend through the wall of the pear-shaped chamber 28 in the drying room 30, in which a coolant, such as water, is placed around the nuclear reactor vessel 24 flows. The coolant is heated by the nuclear reactor, whereby the required Heat transfer for generating electrical energy results. The coolant lines 48 and 50 are connected to a heat exchanger (not shown), which in turn a secondary water supply heats up to generate electric steam Generate energy. The coolant circulates in the coolant lines 48, 50 around the nuclear reactor vessel 24 in such a way that there is no possibility of leakage consists of radioactively contaminated or contaminated coolant.

In Fig. 3, the structure of another known nuclear reactor is shown. In this construction, the pressure vessel 100 is preferably made of reinforced material Concrete, it being advantageous if the inner wall is provided with a steel cladding 102 is.

An opening 104 is provided at the bottom of the pressure vessel 100, which can be closed with a concrete gate 106. The pressure vessel 100 offers an almost insurmountable obstacle to the release of contaminated substances into the atmosphere.

In the pressure vessel 100 there is a nuclear reactor vessel 108, which is surrounded by a cylindrical supporting structure that has an outer diameter which is slightly smaller than the inner diameter of the steel cladding 102, so that there is an annular space 112 around the supporting structure 110.

In particular, a central chamber 114 surrounds the support structure 110 the nuclear reactor vessel 108. Laterally arranged chambers 116 accommodate steam generators 118 suitably wound with coolant lines 120, in FIG which a coolant is circulated around the nuclear reactor vessel 108. The supporting structure 110 forms a lower pressure chamber 122, in the lower part of which there is water 124. A number of inlet openings 126 distributed in the radial direction connect the Pressure chamber 122 with the annular space 112. In addition, there is several (usually 16) Standpipes 128 terminating at openings 130 of central chamber 114, a connection between the central chamber 114 and the pressure chamber 122. The walls 132 and 134 the pressure chamber 122 form a barrier for gases and vapors. At the bottom of each Standpipe 128 is again a distributor head according to the invention 46 provided. A pressure relief valve 121 can be provided in the coolant lines 120 be. If an overpressure arises in the coolant lines 120, the overpressure valve speaks 121, the emerging steam through a standpipe 129 into the pressure chamber 122 is initiated.

The structure of a further nuclear reactor is shown in FIGS. This reactor is constructed similarly to that according to FIG. 1, but with the The difference is that instead of the toroidal pressure chamber 38, several spherical Pressure chambers 150 are provided. A pear-shaped chamber 152 houses the nuclear reactor (not shown) on, and overpressure lines 154 extend from their bottom, which protrude through the walls of the pressure chambers 150 into these and in doing so are bent so that in each case a standpipe 156 results, which is below the surface of a water supply 158 contained in each pressure chamber 150 is sufficient. At the bottom The end of the standpipe 156 is again a distributor head 46 according to the invention intended.

The worst conceivable accident in nuclear reactors, which is shown in Fig. 1 to 5 types, is a break in the primary cooling system to which a loss of coolant, the fuel rods melt and fission products are released. A A break in the coolant pipe has the consequence that the actual nuclear reactor immediately fills the surrounding chamber with steam, causing a rapid increase in pressure. The rapid increase in pressure in the chamber would cause the LuLt to enter the Upper pressure lines and standpipes against the water pressure and the air pressure in the pressure chamber or the pressure chambers is pushed into this at high speed would as the overpressure lines and standpipes in a typical nuclear power plant have an extremely large diameter and also have a large number of standpipes is available. Typically, the standpipes have an inside diameter of about 60 cm, while the overpressure lines have a much larger diameter usually have a diameter of about 140 cm. In an accident A large amount of air is consequently passed through the overpressure lines in the nuclear power plant and standpipes very suddenly deep below the water surface or at the bottom of the Pressure chamber (s) initiated, where a layer of air quickly forms, which the the water above it lifts like a closed body, with the air is compressed above the water surface. In the nuclear power plant according to FIG. 1 one can assume, for example, that the water moves at a speed is thrown against the upper side of the annular pressure chamber 38 at a rate of approximately 3 m / sec would. Due to the inertia of such a large amount of water, their Hitting the top of the pressure chamber 38 is likely to damage the system result in the release of contaminated substances into the atmosphere could result in%.

Similarly, in the case of the nuclear power plant according to FIG. 3, the Standpipes 128 from the central chamber 114 and standpipe 129 from the main relief valve 121 up to about 6 m deep under the water surface in the pressure chamber 122. Typically, the pressure chamber 122 in a system according to FIG.

3 has a diameter of about 30 m and is up to a height of about 10 m filled with water. In the event of a reactor accident or

when the main pressure relief valve responds, a 6 m high water column can be pushed out of the standpipes, namely by air and gases pushed down the 16 standpipes. If then the air emerges at the lower end of the standpipes, there is also a large 2 gas bubble an internal pressure of about 35 to 39 kg / cm, which immediately expand rapidly begins. Due to the inertia, the water keeps moving even when it is the air pressure and the water pressure have equalized, resulting in an underduct in the air bubble leads. Overall, there are thus also oscillating pressure forces a frequency of about 8 Hz, which lead to enormous vibratory forces the walls of the pressure chamber take effect. In many cases, these vibratory forces could be heard or these forces in alternating direction cause considerable damage to the whole Cause buildings.

'; if steam then escapes at the lower end of the standpipes, then results The even more serious problem is that shock cells appear on it can be attributed to the fact that there are strong pressure fluctuations when larger vapor bubbles due to the condensation collapse and water into the hollow spaces falls. At the same time, a violent "boom" can be seen in the wet, when this is heated up by the steam, with a reduction in the condensation effect results.

To overcome the problems listed above, the bottom located under water end of each standpipe in the pressure chamber an inventive Distribution head 46 is provided.

As shown in Fig. 6, the distributor head 46 has a conical baffle member 160, which has a substantially circular disk-shaped base 162, an obliquely curved Wall 164 and a tip 166 has. Line 168 in FIG. 6 can be any the standpipes 44 in FIG. 1, 128 and 129 in FIG. 2 or 156 in FIG. 5 correspond. In addition, the conduit 168 can correspond to any hollow conduit through which a gaseous Medium is expelled under pressure. The lower end 170 of the line 168 is located below the surface of the liquid 172, which is the water in the pressure chambers in Fig. 1 to 5 may correspond. It should be noted, however, that any liquid Medium that adequately absorbs energy and condenses steam, as Liquid 172 can be used.

The conical baffle 160 is such via connecting rods 174 connected to the lower end of the conduit 168 that the tip 166 of the conical Impact member 160 protrudes somewhat into the end of the line 168, so that between the edge at the lower end of the conduit 168 and the sloping wall 164 of the baffle 160 results in an annular constriction 176. The connecting rods 174 are through Welding or other suitable travel attached to the line 168.

Furthermore is on the connecting rods above the lower land 170 of the line 168 and adjacent to this one like a Truncated cone mantle formed skirt 178, which has a single sloping and curved wall 180, which extends between an upper opening 182 and a lower opening 184 enlarged conically. The upper opening 182 has a larger diameter than the line 168 and is just far enough to pass over the connecting rods 174 to fit. The apron is welded to the connecting rods 174 or on otherwise connected so that between the outer wall of the line 168 and the upper edge of the apron or the opening 182 has an annular opening 186 round around the line 168 results.

When air, steam or another gaseous medium through the pipe 168 then flows downward, as indicated by arrow A in FIG. 6 compression occurs between the wall 164 of the impact member 160 and the lower one End 170 of line 168. When the gaseous medium then passes through constriction 176, then there is a mass and moment transfer with the tendency that the liquid 172 is sucked in through the annular opening 186, as indicated by the arrow C. in Fig.

6 is indicated. This suction causes the gaseous Medium mixes turbulently with the sucked liquid before it passes through the lower one Opening 184 of the apron 178 exits. In the annular space between the T.and 164 of the conical baffle 160 and the inner wall 130 of the skirt 178 So there is a turbulent mixing of the gaseous medium and liquid. so that at the point in time at which the mixture exits the lower opening 184, Air, steam or another gaseous medium completely dissolves with the liquid mixed up in a variety of individual Split bubbles are. These individual small bubbles allow pressure energy to be released quickly and rapid condensation of steam, eliminating the problems outlined above be avoided. The liquid 172 is consequently not pushed upwards and Vibrations and shock waves are reduced to a level where none More damage occurs to the pressure chamber; Instead of a single large oscillating one A large number of gas or vapor bubbles occur at the lower end of the line 168 made up of very small bubbles, all of which are asynchronous at different frequencies vibrate, creating vibratory forces created by the expansion and contraction of Gas bubbles are caused, dampened and compensated. Because the individual small gas bubbles also have a larger surface area than a large bubble in the case of steam which exits at the lower end of the line 168, a significantly faster one Condensation on.

According to the invention, another problem is also alleviated, which occurs when a gaseous medium at high pressure escapes from the end of a pipe exit. It is known that gases emerging from such a pipe create shear forces generate like a rocket motor, in accordance with the second tiewtonian Law, namely force = mass x acceleration. That from the end of line 168 exiting ias therefore has the tendency to line 168 upwards to 'r: z'; en. However, the conical impact member 1; O ensures a reduction in this force, since it has a sloping wall, depending on a part of the gaseous .mediums after down court dead ;; raftc exercises. The shear forces are also thereby still further reduces that between the conical baffle 160 and the skirt 178 a turbulent mixing effect occurs.

The present invention thus reduces the upside Thrust forces on line 168 are significant, while these forces, if not diminished would damage the lead 168 or cause it to bend. In nuclear reactor plants, as they were explained with reference to FIGS. 1 to 4, it is typically that bellows or flexible (pipe) connections are provided, which be damaged or destroyed under extreme upward thrust forces could. Here, too, the invention avoids the possibility of such damage.

At this point it should be noted that the present invention Can also be used in various other systems, i.e. not only in nuclear power plants is. For example, in conventional coal-fired power plants there are a number of Pressure valves, from which, when they respond, to relieve excess pressure what is in the system to allow steam to be released directly into the atmosphere undesirable effects such as loud noises, excessive heating and the like leads. In these cases too, the principle of the invention can be applied to advantage will. If you take the overpressure from the overpressure valves via a line, like c; ìe line 158, which blows off in a pressure vessel under a water surface ends, then namely heat and sound energy in the above-described Wisely destroyed.

Other possibilities for the application of the invention arose in natural gas pipeline systems. such @@@@@ lines be with cleaned using extreme pressure to remove moisture and other contaminants, that have accumulated in a pipeline, for example. Usually will the gas used for cleaning is blown directly into the atmosphere, which is very is noisy and to air pollution due to the presence in the pipe to be cleaned Can lead to contamination. Noise is generated during this cleaning process so strong that the companies concerned usually appear in the local newspapers publish a corresponding notice or warning before cleaning, to inform the public about the reason for the noise development, because the noise is so loud that eg even at a distance of several kilometers heard from the exit point. Again, you could use the pressurized gas with an arrangement according to FIG. 6, i.e. with a distributor head 46 according to the invention, Introduce into a liquid in such a way that there is no noise and contaminants be retained in the water supply.

Furthermore, the invention can be used for the effective mixing of gaseous Use media of any kind with any liquids, for example in industry, especially in chemical companies. The distributor head according to the invention 46 represents an effective device for bringing about the desired visual effect because the gaseous medium is divided into a large number of very small gas bubbles which can be easily absorbed by a liquid.

It will be understood that, based on those described above Embodiments, the skilled person numerous possibilities for modifications and Changes are available without affecting the basic idea of the invention would have to leave. Blank page

Claims (3)

Claims. Device for mixing a gaseous medium with a liquid one Medium characterized by the following features: (a) It is a hollow conduit tal68) provided which has an open end (170) through which a gaseous medium is expelled and immersed in a liquid; (b) it is a conical one Impact member (160) is provided, which has an inclined wall (164) which, starting from from a circular disc-shaped base (162) to a tip (166) which disposed adjacent the open lower end (170) of the conduit (168); (c) a hollow annular skirt (178) is provided which has an inclined wall (180) which extends from an upper opening (182) to a lower opening (184) ranges, the upper opening (182) being smaller than the lower opening (184) and wherein the upper opening (182) has the conduit (168) adjacent the lower end (170) surrounds the same and so an annular opening (186) between the line (168) and the upper opening (182) and wherein the lower opening (184) facing away from the open lower end (170) of the line (168) and the base (162) surrounds the conical baffle member (160); so that the gaseous medium which is expelled from the line (168), is mixed with the liquid medium, which is sucked through the annular opening (186), whereby the gaseous Medium at the lower opening (184) of the apron (178) in the form of numerous smaller Gas bubbles emerge. 2. Device for splitting and condensing steam coming from the bottom The end of a hollow tube (168) emerges which is immersed in a water reservoir, characterized by the following features: (a) It is a conical impact member (160) provided, which has an inclined wall (164) which extends from a circular disk-shaped Base (162) extends to a point (166), this point being in the open End (170) of the tube (168) lies; (b) an annular gate (178) is provided, which has a first opening (182) at one end, the diameter of which is slightly larger than the diameter of the tube (168) .. and which on your other End has a second opening (134) which has a larger diameter than the first opening (182), the first opening (182) the pipe (168) adjacent to the end (170) of the same, so that an annular Opening (186) between the tube (168) and the first opening (182) of the skirt results and wherein the second opening (184) projects beyond the end (170) of the tube (168); (c) there are fasteners (174) for fastening the conical baffle member (160) and the skirt (178) provided at the end (170) of the tube (168); so that steam, which emerges from the end (170) of the tube (168) is mixed with water, which is sucked through the annular opening (186), thereby distributing the steam and is condensed. 3. Mixing and distribution device for a nuclear power plant system with one Rernreaktor, a closed dry space container that surrounds the nuclear reactor, a water supply, which circulates in the reactor and is heated by it, at least one pressure chamber which is partially filled with an amount of water, at least a hollow outlet conduit having a first open end which connects to the drying space container is in communication, at least one outlet line which leads into at least one pressure chamber protrudes, wherein a second open end of the at least one outlet line to below the surface of the water in the least a pressure chamber is sufficient, characterized by the following lerlunals: (a) It is a conical impact member (150) is provided, which has a tip (166) and a 'xreiJ disc-shaped base (162), the tip in the second open end (170) of the at least an outlet line (168) immersed in the water in the at least one pressure chamber and wherein the circular disk-shaped base (162) is outside the second open End (17C) of the at least one outlet conduit (168) lies; (b) that an annular Apron (173) is provided which has a first open end with a first opening (182), the diameter of which is greater than the diameter of the at least an outlet line and which has a second open end with a second opening (184), the diameter of which is larger than that of the first opening (182) the apron (178) that the first open end of the apron (178) the at least one Outlet line (168) above the second opening of the at least one outlet line surrounds, which dips below the surface of the water, around an annular opening iiyt>) wisc.len - at the first open end of the apron (173) and the at least qine Outlet line (168) .u and that the second open end of the skirt (173) below the second open end of the at least one outlet conduit (168) is arranged; (c) they are fasteners for securing the apron (178) and the baffle member (160) provided on the at least one outlet line; so that steam, air or radioactively contaminated substances, which in a reactor accident emerge under pressure from the at least one outlet line, mixed with the water which is sucked in through the annular opening (186), so that steam, Air and contaminated substances are distributed and condensed.