Hydrogen igniter and reactor plant having said igniter

FIELD: chemistry.

SUBSTANCE: invention relates to igniting hydrogen which is part of a gas medium. The igniter consists of a housing having openings for inlet and outlet of the gas medium, and filler in the form of bismuth oxide Bi2O3 and/or lead oxide, placed in the housing. The igniter can be used in a nuclear reactor plant.

EFFECT: obtaining a hydrogen igniter which does not contaminate the gas medium, particularly reactor cover gas, with impurities which are hazardous for installation components and/or coolant, for example, lead-bismuth coolant; removing, from the gas medium passing through the igniter, steam formed as a result of igniting hydrogen.

14 cl, 1 dwg

 

The technical field to which the invention relates

The present invention relates to cleaning devices of the gaseous medium from hydrogen, in particular to the recombiner.

The level of technology

In the operation of nuclear reactor systems to maintain the required impurity composition of shielding gas (gas medium), typically a noble gas, requires removal of a protective gas of hydrogen. Cleaning of protective gas from the hydrogen may be done through a recombiner.

From the patent RU 2253915 known recombiner, having in its composition of copper oxide and is capable of passing through it a flow of inert gas (gaseous medium) containing hydrogen. Hydrogen on the copper oxide is oxidized to water, which is fond of inertial flow of gas.

When cleaning the gas environment (shielding gas) and the hydrogen with the help of afterburner possible contamination of the shielding gas impurities of copper or copper oxide. Such impurities can have a negative impact on the structural elements of the reactor and the coolant, for example, to pollute it.

Due to the fact that the water formed in the oxidation of hydrogen on the copper oxide is not removed from the stream of the gaseous medium, the resultant protective gas atmosphere saturated with water vapor, the concentration�Oia which may exceed the permissible value.

Also noteworthy is the relatively low efficiency of the recombiner oxide of copper.

Disclosure of the invention

The object of the present invention is to provide a recombiner, which will not contaminate the gas atmosphere (e.g., inert gas) impurities harmful to the structural elements of the reactor and/or of the coolant, in particular lead-bismuth coolant. An additional object of the present invention is to improve the efficiency of the recombiner. Another additional object of the present invention is the removal of the gaseous fluid passing through the recombiner according to the present invention, water vapor formed as a result of post-combustion of hydrogen.

The object of the present invention is solved by means of the recombiner, which is a part of the gaseous medium consisting of a body having openings for supplying and discharging the gaseous medium, and a filler containing an oxide of bismuth and/or lead oxide, is placed in the housing. In one embodiment, the oxide of bismuth is a Bi2O3and the filler preferably has a granular form.

In the case of the afterburner can be placed in at least one reaction vessel in which is placed a filler. In preemptive vari�NTE perform in the corps also established a distribution pipe, extending from the openings for supplying the gaseous medium through at least one reaction vessel, and the distribution pipe preferably has openings in the side walls in places of passage through the reaction vessel. In addition, at least one reaction vessel preferably has holes for supplying and discharging the gaseous medium.

The casing of the afterburner may be provided with a heater. In a preferred embodiment of the housing has a bottom, a lid and a side wall, and a hole for supplying the gaseous medium is made in the lid, with a hole for discharging the gaseous medium is made in the bottom, and a heater installed on the side wall of the housing. In another embodiment, the recombiner can be connected to a supply conduit connected to the housing of the recombiner with the possibility of a supply of the gaseous medium in the hole for supplying the gaseous medium, and a heater installed on the supply piping.

In a preferential embodiment, the hydrogen recombiner is connected to the refrigerator and the condenser through the discharge line connected to the housing of the recombiner with the possibility of withdrawal of the gaseous medium out of the hole for discharging the gaseous medium in the refrigerator and the condenser.

A gaseous medium flowing through the afterburner, they are mainly�public includes an inert gas.

At solving the problems the present invention is also aimed reactor installation, comprising any of the above variants of the recombiner. In a preferential embodiment of the reactor plant is nuclear, and as the coolant in it is preferably used lead-bismuth coolant.

Thanks to the present invention were able to get the recombiner, which provides the technical result, as the absence of contamination of the gaseous medium impurities harmful to the structural elements of the reactor and/or of the coolant, in particular lead-bismuth coolant. This allows to increase the reliability of the reactor design, which uses such a recombiner and/or the gas cleaning system, and safety of operation of such a reactor.

In addition, thanks to the present invention was able to achieve this technical result, increasing the efficiency of the recombiner, which gives the opportunity to reduce weight and size characteristics of the recombiner and devices that use it in its composition, as well as to lower cost options.

The present invention has provided a receipt and such a technical result, as the removal of gas from the fluid passing through the afterburner hydrogen� in accordance with the present invention, water vapor formed as a result of post-combustion of hydrogen. This increases the reliability of operation of the devices, which use a gaseous medium, and also increases the service life of the gas medium, which reduces labor costs for its replacement, and improves the financial performance due to a reduction in cash costs to replace gas environment.

Brief description of the drawings

Fig.1 shows the recombiner in accordance with the present invention.

The implementation of the invention

The present invention discloses a recombiner, part of the gas medium is performed, preferably using an inert gas, such as helium, neon, argon, krypton, xenon and/or radon. The use of inert gas as a main component of the gaseous medium can improve the efficiency of the use of afterburner and reduce the consumption of filler, as the afterburner will be post-combusted only impurities (in particular hydrogen), and the interaction with inert gas will be out in force inert chemical properties of such gases. The use of inert gas also reduces the impact on the structural elements of the afterburner, such as housing, etc., which increases its lifespan and reduces maintenance costs.

The afterburner consists of a housing with openings for inlet and outlet g�gas environment, and the filler containing the oxide of bismuth and/or lead oxide, is placed in the housing. In that case, if the body contains bismuth and/or lead are not in the form of oxide, as, for example, in the form of metal, this embodiment can also be considered a form of implementation of the present invention, since the metal bismuth can be easily obtained oxide of bismuth, and lead into lead oxide by passing through the afterburner oxygen or a gas environment containing oxygen.

The casing of the afterburner may be made of metal, composite or polymer materials that provide sufficient mechanical strength, temperature resistance, chemical neutrality to a gaseous environment and the filler (bismuth oxide) and the absence or insignificance of secretions, which can contaminate the gaseous medium. In a preferred embodiment the body is made using steel. The casing is mainly made airtight in order for a gaseous medium flowing through the hole inlet, was only out of the hole for discharging the gaseous medium. In this case, provides a more complete interaction of the gaseous medium with filler and more efficient afterburning of hydrogen, and the absence of leakage, thereby improving the safe use of afterburner and reduced pollution of�surrounding environment.

In the case of the afterburner is placed a filler, which is in accordance with the invention is an oxide of bismuth and/or lead oxide. Due to the fact that bismuth and lead are more heavy metals than copper, it is possible to reduce the contamination of the gaseous medium passing through the oxide of bismuth and/or lead oxide, as a more heavy atoms and their compounds are less susceptible to entrainment by the gas environment. In addition, in the case of application of the post-combustion treatment system the gaseous medium from the hydrogen used, for example, in a nuclear reactor with lead-bismuth coolant, the presence of bismuth or lead in a gaseous environment, such as that used as the shielding gas, will not be perceived as contamination of the coolant. In addition, the coolant through the gas medium also will not contaminate the filler afterburner. All this allows to increase the service life of the coolant and filler afterburner.

The principle of operation of the afterburner mainly based on chemical reactions partial recovery of bismuth oxide Bi2O3to BiO with the formation of water vapor:

Bi2O3+H2→2BiO+H2O.

The use of bismuth oxide is copper oxide itself increases the efficiency of post-combustion, however, the use of reaction partial recovery of bismuth oxide allows you to quickl� further increase the efficiency of reburning. Accordingly, in the afterburner preferably, the presence of bismuth oxide Bi2O3and not bismuth oxide BiO, since the first allows a chemical reaction partial recovery, while the second will be the reaction of full recovery with the receipt of bismuth in the metallic form.

On hold reaction partial recovery in a manner that provides higher efficiency, directed the execution of filler in granular form, for example in the form of balls. This prevents the sintering of the filler and thereby increases the life of the filler. The implementation of the filler in the form of granules ensures the manufacturability of the filler and the easy handling of the filler on the stages of placing and extracting the filler from the body of the afterburner, which reduces labor costs and the cost of the afterburner increases the overall ease of implementation of the maintenance on the backburner. Furthermore, the performance of the filler in the form of pellets provides a large area of interaction between bismuth oxide and hydrogen (oxygen), and hence higher efficiency of the process, since the granular filler will have the gaps between the granules between which gas can flow environment when performing pellets in the spherical shape of these gaps will�et guaranteed and maximum size.

Fig.1 shows a preferred embodiment of the recombiner in accordance with the present invention with pipes for supplying and discharging the gaseous medium and a valve for controlling the inlet and outlet of the gaseous medium.

The body of the recombiner shown in Fig.1, consists of a side wall 1, bottom 2 and the cover 3. In shown in Fig.1 embodiment of the afterburner casing made in the form of specially designed for the performance of its functions of the product, however, the casing of the afterburner can be represented by elements of buildings other devices, for example, when placing a filler in intrashell space devices that are part of the cleaning system of the gaseous medium from hydrogen or reactor.

In the cover 3, a hole for supplying the gaseous medium, through the hole inside the combustor is fed with gaseous medium from the inlet pipe 7 connected to the housing of the recombiner with a possibility of a flow of the gaseous medium in the hole for supplying the gaseous medium to implement the afterburning process. In day 2, a hole for discharging the gaseous medium, through the hole of the combustor is given gaseous medium through the discharge pipe 8 connected to the housing of the recombiner with the possibility of withdrawal of the gaseous medium from the hole for resp�Yes gas environment for the implementation of the process of afterburning in the through-flow of the gaseous medium.

Shown in Fig.1 hole made in the lid and bottom of the hull and have a relatively small cross section, however, in other embodiments, the hole sizes can be significantly larger to the extent that in the afterburner missing lid and bottom and a gaseous medium is supplied and discharged through the full cross section of the housing. Such an embodiment of the housing is also in the scope of protection of the present invention. In some embodiments, the outlet hole may be missing, but this reduces the efficiency of the afterburner, as in the presence of the outlet openings is possible to provide more efficient operation of the afterburner in the through-flow of the gaseous medium. In other embodiments, the outlet opening may be located near the inlet hole or different parts of one hole may be used for supplying and discharging the gaseous medium, this variant of implementation of the holes is also in the scope of protection of the present invention.

Supply and discharge lines can be attached to the housing by welding or any other known from the prior art method, ensure sufficient mechanical, thermal and chemical strength as well as not polluting gas medium or filler. Enough tight connection of pipes to the body to supply the gas medium � afterburner without loss. Part of pipelines or pipelines can be fully executed in the form of a single whole with the casing of the afterburner at the stage of making the case, for example, in the form of a pipe extending from the hole, for connection to piping. These options allow you to simplify the connection afterburner with pipelines and included in the scope of protection of the present invention.

The filler 5 in the form of bismuth oxide can be placed in the body of the recombiner, for example on its bottom 2, however, in a preferential embodiment of the present invention, the oxide 5 bismuth, for example in the form of pellets, is placed in one or more reaction containers (baskets) 4. This improves the manufacturability and maintenance of the combustor, since the first filler 5 can be accommodated in the reaction containers 4 and the container 4 can then be placed in the housing of the Converter, eliminating the need to perform a more time-consuming operation of placing the filler material directly inside the body. Furthermore, the use of reaction vessels allows to increase the efficiency of utilization of volume of the housing through the implementation of several levels of placement of the filler.

As shown in Fig.1, in a preferential embodiment, the afterburner installed in the housing of the distribution pipe 9 extending from the holes to the p�of doda the gaseous medium in the lid 3 through at least one reaction vessel 4. The distribution pipe can fail gas medium to the reaction vessel located outside the container, through which it passes, for feeding, for example, from the end of the pipe, however, in the preferred embodiment, the distribution pipe has holes in the side walls in places of passage through the reaction vessel so as to increase the efficiency of feed of the gaseous medium through its distribution on all of the reaction vessels. If you have multiple levels of reaction vessels, as shown in Fig.1, the distributing pipe may be open hole, from which a gaseous medium directly enters the lower reaction vessel, or goes to the bottom of the lower reaction vessel, where it can be drowned out by the bottom of the tank or the special cap, and a gaseous medium can flow to the bottom of the reaction container in this case through the side holes in the distribution pipe. This allows for a more complete passage of the gaseous medium through the reaction vessel and the filler, resulting in increased efficiency of the recombiner, as the gaseous environment is not able to walk to the hole for discharging the gaseous medium in addition to the filler, not proreagirovali with him.

The reaction vessel 4 mainly have openings for supplying and discharging the gaseous medium. In the case if the containers 4 are arranged in several levels and through them, for example, in the center of the containers takes place the distribution pipe 9, as shown in Fig.1, the gaseous medium will be most efficiently through the filler, which will be located between the bottom elements of the containers (in the upper vessel filler will be located between the tank bottom and lid of afterburner), and out through the lateral surface of the containers, for example, to the periphery of the containers 4 to the wall 1 of the casing, from where it will come down to the opening for discharging the gaseous medium in the bottom 2, as shown in Fig.1. Shown in Fig.1 structure of the afterburner optimal from the point of view of the organization of the flow of the gaseous medium to increase the efficiency of post-combustion of hydrogen on the vehicle and ensure the greatest possible uniformity of transformation of the original stock of oxide, preventing further conversion of BiO in Bi metal.

To further increase the efficiency of post-combustion of hydrogen is possible by increasing the temperature of the gaseous medium, and/or filler and/or reaction vessels, and/or housing up to 500°C. This can be done by placing on the body, for example on the side wall 1, the heater 6, consisting of one or more sections, as shown in Fig.1. The heater can be electric or in another form. The building will be heated to heat the gas atmosphere, and heated gas through� environment and/or through distribution pipe and the reaction vessel is heated filler.

In some cases it may be useful to set the heater to a supply pipe for preheating the gaseous medium supplied to the afterburner casing, - this will allow you to apply the gas already heated, which would mean no need for heating of the gas inside the housing, resulting in the combustion of hydrogen may begin immediately after the filing of the gaseous medium in the housing to the filler, which increases the efficiency of the afterburner.

As a result of afterburning of hydrogen leads to the formation of water vapor, which, in the composition of the gas medium are discharged from the combustor. Water vapor in some cases can be undesirable impurities, and the necessary cleaning of the gaseous medium from them. For this treatment system the gaseous medium from the hydrogen may comprise, in addition to the recombiner, the refrigerator, the condenser and the discharge pipe connected to the housing of the recombiner and a fridge with a possibility of discharging the gaseous medium from the hole for discharging the gaseous medium in the refrigerator and the condenser. In the fridge is cooling the gaseous medium, and water vapor condensed in the condenser, and gas atmosphere freely out of the refrigerator and the condenser and can be utilised in purified form. The fridge can be performed in conjunction with Conde�by Sator, or it could be two sequentially installed in the device, connected by a pipeline, which can be viewed as part of the discharge line, or without the use of the pipeline. In addition to the additional purification of the gaseous medium from water vapor, the use of the refrigerator helps to reduce the temperature of the gaseous medium, for example, after heating the Converter to operating temperature.

Describes the recombiner according to the present invention can be used to clean the gaseous medium from the hydrogen, for example, in a reactor, which may be nuclear and in which a coolant can be used with lead-bismuth coolant. The application of the recombiner having the filler oxide of bismuth and/or lead oxide ensure minimum contamination of the lead-bismuth coolant in nuclear reactor.

1. The recombiner, which is a part of the gaseous medium consisting of a body having openings for supplying and discharging the gaseous medium, and a filler containing an oxide of bismuth Bi2O3and/or lead oxide, is placed in the case.

2. Afterburner according to claim 1, characterized in that the filler has a granular form.

3. Afterburner according to claim 1, characterized in that the case comprises at least one response, which will�innovative capacity, where is the filler.

4. Afterburner according to claim 3, characterized in that the enclosure has a distribution pipe extending from the openings for supplying the gaseous medium through at least one reaction vessel, and the distribution pipe has holes in the side walls in places of passage through the reaction vessel.

5. Afterburner according to claim 3, characterized in that at least one reaction vessel has openings for supplying and discharging the gaseous medium.

6. Afterburner according to claim 1, characterized in that the housing is provided with a heater.

7. Afterburner according to claim 6, characterized in that the housing has a bottom, a lid and a side wall, and a hole for supplying the gaseous medium is made in the lid, with a hole for discharging the gaseous medium is made in the bottom, and a heater installed on the side wall of the housing.

8. Afterburner according to claim 1, characterized in that the recombiner is connected to a supply conduit connected to the housing of the recombiner with the possibility of a supply of the gaseous medium in the hole for supplying the gaseous medium, and on the supply piping installed heater.

9. Afterburner according to claim 1, characterized in that the recombiner is connected to the refrigerator and the condenser through the discharge line connected to the housing of the recombiner with both�biscuits from pulling the gaseous medium out of the hole for discharging the gaseous medium in the refrigerator and the condenser.

10. Afterburner according to claim 1, characterized in that the gas atmosphere comprises an inert gas.

11. Reactor installation, comprising a recombiner according to any one of claims. 1-10.

12. Reactor installation according to claim 11, characterized in that it is nuclear.

13. Reactor installation according to claim 12, characterized in that as the coolant it uses a lead-bismuth coolant.

14. Nuclear reactor installation, which is used as a coolant lead-bismuth coolant, having in its composition the recombiner, which is a part of the gaseous medium consisting of a body having openings for supplying and discharging the gaseous medium, and a filler containing an oxide of bismuth and/or lead oxide, is placed in the housing.



 

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2 cl, 1 dwg

FIELD: atomic industry.

SUBSTANCE: proposed line is provided with computer-aided system for contactless control of flaw depth and profile on surface of fuel element can and on end parts including sorting-out device that functions to reject faulty fuel elements. This line is characterized in high capacity and reduced labor consumption.

EFFECT: enlarged functional capabilities, improved quality of fuel elements.

1 cl, 2 dwg

FIELD: nuclear fuel technology.

SUBSTANCE: invention relates to production of pelleted fuel and consists in controlling nuclear fuel for thermal resistance involving preparation for selecting pellets from nuclear fuel lot for measuring diameter, which preparation consists in dedusting. Selected pellets are placed in temperature-stabilized box together with measuring instrument. Diameter of each pellet is them measured and measurement data are entered into computer. Thereafter, pellets are charged into heat treatment vessel, wherein pellets are heated in vacuum at residual pressure not exceeding 7·10-2 Pa at heating velocity not higher than 10°C/min to 100-160°C and held at this temperature at most 2 h, whereupon heating is continued under the same conditions to 1470-1530°C and this temperature is maintained for a period of time not exceeding 4 h, after which hydrogen is fed with flow rate 2-6 L/min. Humidity of gas mix is measured in the heat treatment outlet. If humidity of gas mixture in the heat treatment outlet exceeds 800 ppm, hydrogen feeding is stopped and material is subjected to additional vacuum degassing at residual pressure below 7·10-2 Pa and held at 1470-1530°C in vacuum for further 4 h. Hydrogen feeding is the repeated at 2-6 L/min. If humidity of gas mixture in the heat treatment outlet is below 800 ppm, preceding temperature is maintained not longer than 2 h and raised to 1625-1675°C at velocity 40-60°C/h and then to 1700-1750°C at velocity 15-45°C/h. When outlet humidity of mixture is 500-750 ppm, hydrogen feeding is lowered to 1 L/min. Temperature 1700-1750°C is maintained during 24±2 h, after which pellets are cooled to 1470-1530ºC at velocity not higher than 10°C/min. Hydrogen is replaced with argon and cooling is continued to temperature not higher than 40°C, which temperature is further maintained. Outside diameter of each pellet from the selection is measured to find average diameter of pellets before and after heat treatment in order to calculate residual sintering ability. When this parameter equals 0.0-0.4%, total lot of pellets is used in fuel elements and in case of exceeding or negative residual sintering ability the total lot of pellets is rejected.

EFFECT: improved pellet quality control.

2 dwg

FIELD: power engineering; evaluating burnout margin in nuclear power units.

SUBSTANCE: proposed method intended for use in VVER or RBMK, or other similar reactor units includes setting of desired operating parameters at inlet of fuel assembly, power supply to fuel assembly, variation of fuel assembly power, measurement of wall temperature of fuel element (or simulator thereof), detection of burnout moment by comparing wall temperatures at different power values of fuel assembly, evaluation of burnout margin by comparing critical heat flux and heat fluxes at rated parameters of fuel assembly, burnout being recognized by first wall temperature increase disproportional relative to power variation. Power is supplied to separate groups of fuel elements and/or separate fuel elements (or simulators thereof); this power supplied to separate groups of fuel elements and/or to separate fuel elements is varied to ensure conditions at fuel element outlet equal to those preset , where G is water flow through fuel element, kg/s; iout, iin is coolant enthalpy at fuel element outlet and inlet, respectively, kJ/kg; Nδi is power released at balanced fuel elements (or simulators thereof) where burnout is not detected, kW; n is number of balanced fuel elements; Nbrn.i is power released at fuel elements (or element) where burnout is detected; m is number of fuel elements where burnout is detected, m ≥ 1; d is fuel element diameter, mm.

EFFECT: enhanced precision of evaluating burnout margin for nuclear power plant channels.

1 cl, 2 dwg

FIELD: analytical methods in nuclear engineering.

SUBSTANCE: invention relates to analysis of fissile materials by radiation techniques and intended for on-line control of uranium hexafluoride concentration in gas streams of isotope-separation uranium processes. Control method comprises measuring, within selected time interval, intensity of gamma-emission of uranium-235, temperature, and uranium hexafluoride gas phase pressure in measuring chamber. Averaged data are processed to create uranium hexafluoride canal in measuring chamber. Thereafter, measurements are performed within a time interval composed of a series of time gaps and average values are then computed for above-indicated parameters for each time gap and measurement data for the total time interval are computed as averaged values of average values in time gaps. Intensity of gamma-emission of uranium-235, temperature, and pressure, when computing current value of mass fraction of uranium-235 isotope, are determined from averaged measurement data obtained in identical time intervals at variation in current time by a value equal to value of time gap of the time interval. Computed value of mass fraction of uranium-235 isotope is attached to current time within the time interval of measurement. Method is implemented with the aid of measuring system, which contains: measuring chamber provided with inlet and outlet connecting pipes, detection unit, and temperature and pressure sensors, connected to uranium hexafluoride gas collector over inlet connecting pipe; controller with electric pulse counters and gamma specter analyzer; signal adapters; internal information bus; and information collection, management, and processing unit. Controller is supplemented by at least three discriminators and one timer, discriminator being connected to gamma-emission detector output whereas output of each discriminator is connected to input of individual electric pulse counter, whose second input is coupled with timer output. Adapter timer output is connected to internal information bus over information exchange line. Information collection, management, and processing unit is bound to local controlling computer network over external interface network.

EFFECT: enabled quick response in case of emergency deviations of uranium hexafluoride stream concentration, reduced plant configuration rearrangement at variation in concentration of starting and commercial uranium hexafluoride, and eliminated production of substandard product.

24 cl, 5 dwg

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