WO2007104831A1

WO2007104831A1 - Igniter, fuel and reactor

Info

Publication number: WO2007104831A1
Application number: PCT/FI2007/000063
Authority: WO
Inventors: Reijo Lappalainen; Lasse Pulli; Juha MÄKITALO; Sampo YLÄTALO; Vesa MYLLYMÄKI
Original assignee: Picodeon Ltd Oy
Priority date: 2006-03-14
Filing date: 2007-03-14
Publication date: 2007-09-20
Also published as: FI20060241A0; FI20060241L

Abstract

The invention discloses an igniter, a fuel, and a reactor in which the former two can be used in order to achieve a fuel reaction. The igniter arrangement comprises an electromagnetic holder means (101) to hold, in a non-contacting manner, a reactant (104) in the reaction volume of the igniter, a temperature regulating means (102) for controlling the temperature of the reactant (104), and a radiation means (103) for radiating the reactant in order to initiate a reaction in the said reaction volume. The reactor includes an igniter arrangement for initiating a nuclear reaction in a reactant in a reaction volume of the reactor, a feeding means (201) for feeding a nuclear fuel into the said reaction volume, and a heat exchanger arrangement (202) for transmitting heat out of the reaction volume. The invention also discloses an arrangement for controlling a reaction.

Description

Igniter, fuel and reactor

In general the invention pertains to low temperature physics, but more particularly to the application of low temperature physics to achieve a reaction in very cold matter, in the manner defined in the preamble of the independent claim directed to an igniter arrangement. The invention also pertains to a reactor in the manner defined in the preamble of the independent claim directed to a reactor. The invention also pertains to a fuel capsule in the manner defined in the preamble of the independent claim directed to a fuel capsule. The invention also pertains to a fuel in the manner defined in the preamble of the independent claim directed to a fuel. The invention also pertains to a control arrangement for controlling a nuclear reaction in the manner defined in the preamble of the independent claim directed to a control arrangement.

Fossil fuels have played quite an important role in the production of energy around the world. New energy production techniques have been researched globally because of the chance that fossil fuels, as non-renewable natural resources, may soon become scarce, if not completely exhausted. As such it is known to produce e.g. oil and/or gasoline synthetically, but so doing, the price of the fuel becomes rather high compared e.g. to the prices charged at the priority date of this application and, therefore, such synthetic production is not commercially viable, yet. On the other hand, bio-fuels, for example, provide an opportunity to produce environment-friendly fuels whereby fossil fuels can be replaced at least partially and the freed carbon dioxide can be brought back into circulation, so that a global transition to almost exclusive bio-fuel use could restrain the greenhouse effect quite considerably.

On the other hand, certain problems are associated with coal, for instance, as toxic gases are generated in a temperature-dependent manner so that the oxides of nitrogen and sulfur, for example, can cause harmful emissions as they escape from the combustion gases. Furthermore, various combustion techniques are quite often riddled with particle emissions, and in spite of restrictions and use of purifiers, fine-particle emissions will occur in particle size categories of the so-called penetration window. Penetration window refers to fine particle sizes of 0.1 to 3 μm, and the various purifying mechanisms work well for particles bigger and smaller than that, but their effectiveness drops when approaching the penetration window both from the smaller and the bigger end. It has been found that a high concentration of fine particles in urban air correlates with mortality. In addition, particle emissions from small-scale burning, e.g. during the heating season to substitute for expensive electricity, burden the atmosphere, especially as no purification mechanisms are required in small-scale burning in contrast to incineration plants of industrial scale.

Energy production based on nuclear power also produces nuclear waste; when such waste is stored in geologically stable strata, the risk of substances in the nuclear waste becoming free is significantly reduced. On the other hand, fission- based nuclear energy production systems involve the possibility of making nuclear weapons by means of breeder reactors, for instance.

As an alternative to fission it has been suggested that fusion be utilized in the production of nuclear energy, but despite the fairly long history of fusion from the early days of the hydrogen bomb up to the priority date of this application, controlling the reaction itself has proved rather a difficult challenge. A significant problem relates to the control of the plasma to be fused at temperatures at which nuclear reactions like those occurring in the sun, or the like, would be possible. Especially the heating of the plasma to temperatures equaling those inside a star and, in particular, maintaining such temperatures, requires energy and, therefore, the efficiency of modern-day experimental reactors may remain rather low. Especially if it is not have been possible to fuse such amounts of matter that would enable a self- sustaining reaction in controllable manner.

Fusion has been studied as a clean source for energy from the early 50's. Various problems relate to the fusion and when dealing with high temperatures it is important that the high temperature plasma do not touch the holding equipment.

Various known techniques that use electrostatic and/or magnetic fields to hold non-contacting way matter that is charged are known as such. Such techniques comprise solid or liquid phase matter to be suspended as shown in aerosol related studies, made and/or referred in the article made by J. Davis (1997) (J. E. Davis, A history of single aerosol particle levitation, Aerosol science and technology 26:212-254, Elsevier,1997 [3]). The article describes how to hold and handle single charged particles in a non-touched way. The article deals with several aspects of using quadrupole type electric fields for holding single particles in a non- contacting way and teach how to inject individual particle into such an ion-trap operated by electric field to capture the particle into it. The survey covers a time-line from the early studies of Millikann's to Paul and Rather (1955) and up to the optical molasses to hold particles. Also plasma has been indicated to be handled by electric fields. It is known a "fu- sor" from a patent publication by Hirsch and Meeks that fusor is arranged to handle plasma by the electric fields.

Tokamak type reactors of their various generations, among the other magnetic confinement devices, have been used in experiments for controlling and confining a plasma in high temperature into a toroidal magnetic field in an non-contacting way. In many approaches to get the fusion to start, the temperature appears to be rised very high for getting the fusion to happen in the star-interior like conditions.

The most modern tokamak-type reactor is known as such from the ITER and the related pages in the Internet (www.iter.org).

An ongoing fusion reaction reach very easily temperatures up to 100 MK or may be even higher up to the temperatures as high as in the core of a certain type of stars. The heating of the fuel that participate into the reaction as plasma can take much energy for the matter to reach the required temperatures that required in such a kinetic approach by heating. Thus, the energy cost, it is also suggested to go around the heating problem by utilising a nuclear reaction between certain types of hydrogen atoms and myons for producing a fusion reaction, even in ambient temperatures, which fusion is known as such as a cold-fusion. Cold fusion as such suffers the problem of the short lifetime (in μs scale) of myons, which may be one reason not to break through as a power source. The short lifetime of the myons affects to the myon concentration to be maintained in the fuel for the fusion events and thus the myon production may consume even more energy than what were released in the yielding individual fusion events in successful collisions between the hydrogen atoms and myons.

At the priority date of the current application, Bose-Einstein condensate (BEC) as such is known in practice to be manufactured. BEC has been made for instance from a bosonic lithium isotope as such by using a magnetic trapping techniques to maintain as complete isolation as possible from the surrounding of the matter to be condensed to BEC. The manufacturing as such comprises utilising laser cooling and evaporative techniques to reach the required temperatures.

It is also shown in a patent publication US2005/0129159 A1 a technique that is based on Bose-Einstein-condensate which put a radiation pressure shock on BEC by a laser radiation. The techniques relates to at its nearest to the preamble of an independent claim concerning the igniter arrangement. An object of the invention is to solve or at least alleviate the problems related to the prior art. By means of the invention it is possible to avoid the problems caused by the combustion originating nitrogen and sulfur oxides resulting from combustion processes in association with electricity production as well as particle emissions related to coal used as an energy source. An object of the invention is to achieve a cold ignition of fusion in a quite low temperature with a quite small amount of energy, using an igniter arrangement according to the invention so that actual preheating of nuclear fuel is not needed and thus providing an optional route to the extensive plasma pre-heating as such. Another related object of the invention is to control the plasma and/or the reaction to occur in the reaction volume by ablation formed moderator and/or absorber to be injected into the plasma. Still a related object of the invention is to purify, manufacture and dose nuclear fuel into the reactor.

An igniter arrangement according to the invention is characterized in that which is presented in the characterizing part of the independent claim directed to an igniter arrangement. A reactor according to the invention is characterized in that which is presented in the characterizing part of the independent claim directed to a reactor. A fuel capsule according to the invention is characterized in that which is presented in the characterizing part of the independent claim directed to a fuel capsule. A fuel according to the invention is characterized in that which is presented in the characterizing part of the independent claim directed to a fuel. A control arrangement for controlling a nuclear reaction according to the invention is characterized in that which is presented in the characterizing part of the independent claim directed to a control arrangement.

Other embodiments of the invention are presented in dependent claims. Embodiments of the invention can be combined where applicable.

An igniter arrangement according to the invention comprises

- an electromagnetic holder means to hold, in a non-contacting manner, the reactant in the reaction volume of the igniter,

- a temperature regulating means for controlling the temperature of the reactant, and

- a radiation means for radiating the reactant in order to initiate a reaction in the said reaction volume. In an igniter arrangement according to an embodiment of the invention the temperature regulating means comprises at least a laser cooling arrangement adapted so as to cool the reactant.

In an igniter arrangement according to an embodiment of the invention the temperature regulating means comprises additionally or alternatively a magnetic cooling arrangement adapted so as to cool the reactant.

In an igniter arrangement according to an embodiment of the invention the temperature regulating means is arranged so as to produce a Bose-Einstein condensate.

In an igniter arrangement according to an embodiment of the invention the reactant comprises bosons.

In an igniter arrangement according to an embodiment of the invention the reactant comprises matter comprised of fermions.

In an igniter arrangement according to an embodiment of the invention the reactant comprises matter comprised of Cooper pairs.

In an igniter arrangement according to an embodiment of the invention the radiation means comprises a means for producing particle radiation and/or directing it to the said reactant.

In an igniter arrangement according to an embodiment of the invention the said particle radiation comprises fermions.

An igniter arrangement according to an embodiment of the invention includes a means for adjusting the energy of the said fermions to correspond to the energy needed for producing a thermonuclear reaction in the said reactant.

In an igniter arrangement according to an embodiment of the invention the said fermions are neutrons, protons, electrons and/or mesons.

An igniter arrangement according to an embodiment of the invention comprises an alfa source based on polonium amerikium and/or californium adapted so as to produce a fermion by means of a target.

An igniter arrangement according to an embodiment of the invention comprises a reflector for directing neutrons or other fermions into the reactant. An igniter arrangement according to an embodiment of the invention comprises a lattice for focusing fermions as wave motion into the reactant.

In an igniter arrangement according to the invention the temperature regulating means comprises a laser cooling apparatus with a turbine scanner.

A reactor according to an embodiment of the invention comprises

- an igniter arrangement according to any embodiment of the invention to initiate a nuclear reaction in a reactant in the reactor volume,

- a feeding means for feeding nuclear fuel into the said reaction volume,

- a heat exchanger arrangement for transmitting heat out of the reactor volume.

In a reactor according to an embodiment of the invention the said nuclear fuel is a powder. In a reactor according to an embodiment of the invention the said powder has a monodisperse mode in its particle size distribution.

In a reactor according to an embodiment of the invention the said feeding means is arranged so as to feed charged particles into the reactor, the particle size of the charged particles being in accordance with the electrical mobility of the said monodisperse mode.

In a reactor according to an embodiment of the invention the charge of the said charged particles is at least equal to the elementary charge or a multiple thereof.

In a reactor according to an embodiment of the invention the average size of the particles of the said monodisperse mode is between 1 and 100 nm.

In a reactor according to an embodiment of the invention the feeding means is arranged so as to transfer powder particles in the vicinity of the igniter when the latter is igniting, so that the nuclear reaction can be sustained.

A reactor according to an embodiment of the invention includes a means for controlling plasma. A reactor according to an embodiment of the invention includes a means for boosting the ignition in an igniter according to an embodiment of the invention and/or raising the temperature in order to fuse the fuel.

A reactor according to an embodiment of the invention includes a means for controlling fusible gas and/or plasma. The said means comprises a means for controlling the temperature of the gas and/or plasma in order to sustain a fusion following an ignition performed by an igniter, in an area larger than the impact range of the igniter. According to an embodiment of the invention the said means comprises a high-power laser with an ablation means for ablating a neutron absorber and feeding and mixing it into the gas and/or plasma to be fused. According to an embodiment of the invention the said means also includes a feeding means and/or a control means arranged so as to control the feeding of the said neutron absorber, control the fusion reaction and/or stop the fusion reaction.

A reactor according to an embodiment of the invention comprises a maintenance system that is based on the infrastructure of a most modern tokamak-type reactor as known as such at the filing date. Thus, according to an embodiment of the invention, the reactor can comprise a similar kind of an infrastructure as known from the ITER-concept to handle plasma as such, but however, according to an embodiment of the invention, as modified to accept nuclear fuel injected in particle form into the reactor volume.

According to an embodiment of the invention, the reactor is as a tokamak-type- reactor. According to an embodiment of the invention, the reactor of a tokamak- type comprises means to accept an igniter arrangement according to an embodiment of the invention.

According to an embodiment of the invention, the reactor comprises in addition to the infrastructure to handle and/or maintain the plasma-controlling, a control arrangement arranged to feed at least one of the following substances in plasma mode:

- a moderator to adjust via the concentration a fermion kinetic energy that is released in the reaction,

- an absorber or a neutron poison to adjust via the concentration a fermion concentration of fermions released in the reaction, and - nuclear fuel to adjust via the concentration the fuel concentration in certain part of the reactor for maintaining the reaction releasing fermions and/or bosons.

According to an embodiment of the invention, the released fermions are neutrons. According to an embodiment of the invention, the released bosons comprise nucleus comprising a structure comprising helium-isotope structure.

According to an embodiment of the invention, the reactor comprises a neutron poison mantel surrounding the reactors core in which the reactor is occurring. According to an embodiment of the invention, the neutron poison mantel is at lest in one region in plasma phase surrounding the reactor core arranged to be maintained for protection of the reactor's structures from released neutrons. So, it is possible to protect the outer parts of the reactor, which may comprise a complex and very expensive supporting system form the nuclear reactions in the materials casued by the neutrons released in the reactor. In one embodiment, the neutron poison is arranged into the reactor in plasma phase, but in another embodiment implemented optionally or in addition by a solid and/or liquid phase of the material.

A fuel capsule according to an embodiment of the invention for storing a reactant of the igniter comprises a cavity containing a reactant as a fuel within a shell impervious to the reactant, where the fuel is a nuclear fuel.

In a fuel capsule, according to an embodiment of the invention the reactant is a substance which, when cooled, produces a Bose-Einstein condensate.

In a fuel capsule according to an embodiment of the invention the shell is of an optically transparent material to facilitate laser cooling.

In a fuel capsule according to an embodiment of the invention the shell is of a material permeable to a magnetic field to facilitate magnetic cooling.

In a fuel capsule according to an embodiment of the invention the shell comprises magnetic material arranged so as to generate a magnetic field in the said cavity to facilitate magnetic cooling.

In a fuel capsule according to an embodiment of the invention the said cavity comprises a reflector surface to reflect fermions into a reactant in the said cavity. In a fuel capsule according to an embodiment of the invention the said cavity comprises a spot not coated by a reflector surface to direct fermions into the said cavity and especially into a reactant therein.

A fuel capsule according to an embodiment of the invention comprises ⁴He as reactant. According to another embodiment of the invention the nucleus of the reactant is a multiple of the nucleus Of ⁴He.

A fuel according to an embodiment of the invention comprises, as a nuclear fuel in powder form, at least one of the following H, D, T, Li, C, N, O, Be, B, F, Na in the elemental and/or compound form. According to an embodiment of the invention the said powder comprises particle matter which is monodisperse in its electrical mobility. According to an embodiment of the invention the said powder comprises LiD, LiH, LiT Be and/or B. As B can be used as such also to absorb neutrons, it can be used as neutron poison in small concentrations to adjust a reaction of other said substances to make up the reaction conditions in a controllable manner.

Embodiments of the invention that pertain especially to an igniter utilize properties of the Bose-Einstein condensate so that the matter condensed within the condensate is in a small volume cooled down to near absolute zero, e.g. by laser cooling and/or magnetic cooling arrangements. An idea of such an embodiment of the invention is that when the condensate is bombarded with single fermions, e.g. neutrons, a nuclear reaction will take place resulting in that more neutrons, for example, will be produced in the condensate comprised of bosons or particles which essentially behave like bosons, so that a nuclear chain reaction will start and at the same time the bosons or the particles which essentially behave like bosons will be turned into fermions by the reaction started by the neutrons. As there is a great number atom of the condensate in the same volume/region, the chain reaction may start very quickly so that a remarkable increase in the energy density can be achieved in the condensate.

The heat released by the igniter makes it possible for the nuclear fuel fed in powder form at the point of reaction to take part in the reaction when a particle in the powder heats up and reaches conditions in which a fusion will take place in the particle, like in a hydrogen bomb, for instance, but on a considerably smaller scale. The amount of nuclear fuel fused at a time can be controlled through the particle size of the powder. Powder particles can be stored/controlled using electric and/or magnetic fields according to the prior art, e.g. by quadrupole-type devices like the one presented by Paul and Rather (1955) [1].

Furthermore, according to an embodiment of the invention, a liquid/gas phase around the igniter can be used to control the energy released initially.

A control arrangement according to an embodiment of the invention for controlling a nuclear reaction in certain part of the reaction volume of the reactor comprises an ablation means adapted to ablate a substance for controlling the nuclear reaction of a fuel used in the reaction by the ablated substance.

In a control arrangement according to an embodiment of the invention for controlling a nuclear reaction the ablated substance comprises at least a neutron absorber.

In a control arrangement according to an embodiment of the invention for controlling a nuclear reaction the ablated substance comprises at least a moderator for changing the velocity of neutrons.

In a control arrangement according to an embodiment of the invention for controlling a nuclear reaction the arrangement comprises, in the arrangement for feeding a substance to be ablated, a means for changing the geometry of a jet of the ablated substance, adapted so as to optimize the said jet for sustaining and/or stopping the reaction.

The control arrangement according an embodiment of the invention comprises means to control by ablation a neutron absorber and/or a neutron poison that comprises a substance that is Hydrogen, Carbon, Beryllium, Boron, Hafnium, Platinum, Xenon, and/or a compound of said at least two substances, a perform of the substance to be released in the reactor or a mixture of the before mentioned.

An implementation according to an embodiment of the invention to control a nuclear reaction applies modern high-power pulse lasers in various ways. Especially in recent years, there has been rapid development in the solid state pulsed laser technology in the picosecond and/or femtosecond category. Such lasers can, using implementations existing at the priority date of this application, direct powers of several tens of watts in a very focused manner and at high repetition frequencies onto surfaces of materials, such as e.g. absorber substance and/or moderator substance. The power values mentioned are examples and as such do not limit the laser power. Such lasers make it possible to produce high-energy matter plasma jets from different materials by controllably ablating the surface layer of a substance. Thus energy is efficiently transmitted to the plasma and energy losses are very small. The wavelength, pulse length, and repetition frequency of the lasers can be varied for different uses, whereby also the jet of matter coming from the absorber and/or moderator substance can be controlled.

According to an embodiment of the invention the nuclear reaction is a fusion reaction.

According to an embodiment of the invention the nuclear reaction is a fission reaction, where the moderator and/or neutron absorber must be chosen from the point of view of sustaining/stopping the fission reaction.

Embodiments of the invention are discussed below through examples and with reference to the drawings in which

figure 1 illustrates an igniter according to an embodiment of the invention,

figure 2 illustrates a reactor according to an embodiment of the invention,

figure 3 illustrates a fuel capsule according to an embodiment of the invention,

figure 4 illustrates a fuel according to an embodiment of the invention, and

figure 5 illustrates an arrangement for controlling a nuclear reaction in accordance with an embodiment of the invention.

Let it be said, for the avoidance of doubt, that the expression 'fuel¹ used in this application in connection with the various embodiments of the invention refers to a nuclear fuel, a material from which nuclear energy can be released without a chemical reaction as such. Examples of nuclear fuels include certain fissionable isotopes of uranium, plutonium and thorium, also in compositions made for reactor use according to the prior art. Examples of fusion fuels include hydrogen and helium, but also carbon, nitrogen, and oxygen (especially in connection with the CNO reaction, also known as carbon cycle reaction from certain stars). Let it also be said that in the right conditions any material from which energy can be released through a fusion reaction can be used as nuclear fuel, fusible material, so that elements lighter than iron and/or their mutual compounds as well as various isotope variations of the said substances can be used as nuclear fuel for fusion. However, advantageous are substances which as such will not heavily absorb neutrons, generated in the fusion reaction to sustain the chain reaction.

Figure 1 illustrates an igniter arrangement according to an embodiment of the invention. The electromagnetic holder means 101 can be arranged according to the prior art, in a manner similar to that described in Paul, W. and Raether, M. (1955): Das Elektrische Massenfilter, Z. Phys. 140:262273 [1], also partly described in [3]. According to an embodiment of the invention the holder means may also be arranged using rods bent into rings, as a modification of [1]. In an embodiment of the invention the holder means can be implemented using a pico-balance type concept which as such is known (Davis, E. J. (1985): Electrodynamic Balance Stability Characteristics and Applications to Study of Aerocolloidal Particles. Lang- muirVol. 1, 3:379-387 [2].

In an igniter arrangement according to an embodiment of the invention the temperature regulating means T comprises a laser cooling apparatus to utilize laser radiation for cooling a reactant controlled by the holder means. In the said laser cooling apparatus, in its radiation transmission line, it is possible to also use a turbine scanner to direct the radiation. A turbine scanner in the radiation transmission line is advantageous when one wants to facilitate a controlled direction of a high- power and high-frequency pulsed laser power onto a desired area or areas. In an embodiment of the invention, the temperature regulating means T also comprises a magnetic cooling means so that temperatures close enough to the absolute zero can be reached when cooling the reactant, i.e. temperatures which enable the formation of the Bose-Einstein condensate.

According to an embodiment of the invention, the radiation means FG 103 are intended to radiate the reactant in such a state where it is sufficiently formed of the Bose-Einstein condensate (B-E-, also BEC in the drawings). Then the reactant is in a state where individual atoms are hardly distinguishable so that also the density of the condensate is high. Thus, by radiating the condensate with fermions, e.g. fermions having energies suitable for starting a nuclear reaction, it is possible to achieve in a small reaction volume a considerable number of nuclear reactions so that energy can be released when the nuclei react with each other while at the same time at least some of the nuclei of the matter are changed into fermions by the neutrons released in the chain reaction. The radiation means as such can be in accordance with the prior art, e.g. neutron generator means known from the thermonuclear bomb, with polonium ²¹⁰Po, but without limiting the invention to any particular neutron generating technique of the prior art. Neutrons can be generated by bombarding a suitable target with alpha particles originating to other sources than polonium and/or subjecting it to alpha radiation so that the target will then release neutrons. According to an embodiment of the invention, the material which releases neutrons can be arranged so as to surround the fuel capsule.

According to an embodiment of the invention, the temperature regulation means comprises means that are arranged for an evaporative cooling. According to an embodiment of the invention, the capsule comprises a molecule sieve leading through from the interior side of the capsule to outer side of the capsule so, that the sieve is arranged to be sealable by an ensemble of mems valves comprising at least one mems-valve in said ensemble. Sealing can be thus based on electric and/or magnetic interaction with the valve, which according to an embodiment comprises a locking mechanism to lock the capsule.

According to an alternative embodiment the capsule can be used in another kind of reactor. According to such an embodiment, by selecting the capsule shell thickness and the material so to comprise a moderator the shell can be used to slow down neutrons, and the valve can be arranged to operate so that it releases gaseous substances outwards.

The arrows drawn in Figure 1 to depict an electric field E and magnetic field M are illustrative only and do not limit the direction, magnitude, duration, amplitude and/or waveform of the said fields in any way. One of the said fields holds the fuel capsule 300 in a non-contacting manner within the scope of operation of the radiation means. Dashed line 105 in Figure 1 illustrates neutron radiation for radiating the Bose-Einstein condensate. Box 106 illustrates especially the cooling of the fuel capsule 300 by the temperature regulating means T, without, however, limiting the invention to the fuel capsule and/or the nuclear fuel possibly contained therein.

Figure 2 illustrates a reactor according to an embodiment of the invention where the substance to be fused is fed, as nano-powder, in the vicinity of the igniter at the moment of ignition. The feeding may be arranged e.g. using an electric field, moving charged powder particles in a quadrupole field in a manner according to [1], for instance. The grain size of the fuel powder may be e.g. between 1 and 100 nm, without, however, limiting the invention to that size. The composition of the powder grains may include e.g. lithium deutride (LID, LI²H) or some other fusible material, known as such from the thermonuclear bomb, without limiting the invention to materials which are known to be used. A reactor according to an embodiment of the invention comprises a conventional fusion reactor arrangement, known as such as research equipment, in which the fusible plasma is controlled by a magnetic field, for example, and which additionally comprises an igniter according to an embodiment of the invention for starting a fusion reaction. According to an embodiment of the invention the reactor also includes a fuel powder feeding means for feeding the fuel, in a non-contacting manner, into that part of the reactor in which the reaction is going on and/or about to start.

A nano-powder according to an embodiment of the invention, which can be used as nuclear fuel in a fusion, can nowadays be manufactured through many different physical and/or chemical methods. One possibility is to produce powders directly from powder materials by applying ablation. In addition, laser ablation can be used to purify and enrich source material so that material from dismantled nuclear weapons, for example, can be utilized. Particles of a powder having a certain mobility can be controllably handled with electric methods. According to an embodiment of the invention, the ablated material can be cooled down to the normal temperatures, so that the vapors would nucleate to form particles that can be allowed to grow via condensation to certain size. As charged nano-particles as such appear mainly with single charge, they can be classified according to the electrical mobility and thus the size. Such a nuclear fuel powder can be collected by a filter, impactor and/or an electrostatic precipitator. However, the nuclear fuel manufacturing is not limited only to the mentioned, but a skilled man in the art realizes that the moderator, absorber and/or other substances can be purified and/or collected via the ablation. According to an embodiment of the invention, such nuclear fuel can be purified and/or collected onto lamella so to be used via ablation in fusion related activities, or other uses. According to an embodiment of the invention, the electrical mobility of the nuclear fuel powder can be used to classify the particle size and thus to control the mass to be fed into the reactor. Combining mechanical mobility properties, such as inertia for instance, in a medium and the electrical mobility, the particles can be separated and differently sized particles can be utilized for dosing the powder mass into the reactor. So defining a first electrical mobility for a first particle size having a certain first charge and so defining a second electrical mobility for a second particle size having a certain second charge so that said first and second electrical motilities are same, so facilitating means to control the reactor power via the particle size.

According to an embodiment of the invention the reactor is arranged to be in the form of a ring so that the fusion can be started in a sector of the ring where the fusion takes place. The fusion can then be arranged to proceed in the ring from a sector to another by feeding a nuclear fuel into a sector next to the fusion in the direction of the cycle, which fuel is pre-heated in an embodiment of the invention, but in another embodiment of the invention it is to be ignited by an igniter according to an embodiment of the invention. There may be a plurality of sectors, and in one embodiment of the invention, nuclear fuel is fed in a first sector, the fuel is made to react in a second sector, reaction transfer from the said second to a third sector is prepared in a third sector, and reaction products possibly remaining are removed in a fourth sector. According to an embodiment of the invention there is a plurality of sectors in the same ring so that one and the same stage can be taking place simultaneously or essentially simultaneously in more than one sector. In an alternative embodiment of the invention, the progress of the reaction can be limited in some other sectors by feeding neutron absorber into the reactor to produce a layer and/or region which heavily absorbs neutrons, such that the neutron absorber as such needs not remain in the reactor space but it can be arranged so as to pass through that part of the reactor space where the reaction is not to take place. The concentration of the absorber can thus be used to control the number of absorbed neutrons and, hence, to control the absorption of neutrons released in the chain reaction in the nuclear fuel itself in certain parts of the reactor. According to an embodiment of the invention, just enough neutron absorber is produced that the nuclear reaction will not start. According to another embodiment of the invention, a neutron absorber is used to create a curtain largely impenetrable to neutrons so as to confine the fusion in a certain space. According to an embodiment of the invention the neutron absorber is produced by ablating a material which contains it. Ablation can be done in a controlled manner using a high-power pulse laser which facilitates sufficient yield for the purpose. According to an embodiment of the invention the laser radiation transmission line includes a turbine scanner by means of which ablation can be controlled fast and in a very controlled manner in a wide area. According to an embodiment of the invention the nuclear reaction can be controlled by feeding into the reactor a moderator, such as carbon, so as to control the energy of the neutrons released in the reaction, purposely fed there and/or coming from the environment, to correspond to the energy of neutrons suitable for the fusion reaction. According to an embodiment of the invention the moderator is carbon. According to an embodiment of the invention a moderator slows down neutrons so that they react with the nuclear fuel in that part of the reactor, in that sector, in which the reaction is meant to take place.

In an embodiment of the invention the neutron absorber and/or moderator produced through ablation is arranged in a group of jets of matter comprised of plasma and arranged to travel into the fused plasma through that part of the reactor where the fusion reaction is taking place and/or pass through the plasma in that part of the reactor. The jets of matter may be arranged in a geometry which is advantageous from the point of view of neutron absorption/deceleration and may be comprised of different materials. In one case, for example, the jets are arranged to penetrate into the reaction area in a control rod like manner. In that case, according to an embodiment of the invention, the control effect of the neutron absorber/moderator can be controlled by controlling the concentration, composition and/or geometric width of the jet of matter in proportion to the reaction area where the fusion is meant to take place.

Figure 3 illustrates a fuel capsule according to an embodiment of the invention including, for the purpose of storing a reactant but also for keeping it at a certain volume, a cavity which can be fabricated of or coated with a neutron-reflecting material. According to an embodiment of the invention the said fuel capsule is arranged so as to be implemented on the nano-scale. The fact is, namely, that the temperatures reached at the start of the fusion of ⁴He, for instance, may be so high that they can sustain a nuclear reaction in the carbon of the diamond material used in the shell structure, e.g. in a cycle according to the CNO chain, so that the additional energy released may cause unpredictable consequences and/or destroy the equipment.

In an embodiment of the invention, the reactant used is ⁴He. Since, at the temperatures in question, helium is in the form of He-2, which is a sort of super-fluid the internal friction of which is almost non-existent, the helium is then, in an embodiment of the invention, packed in a capsule which is tightly sealed. A nuclear fuel capsule according to an embodiment of the invention has a diamond shell, for instance, which includes a closed cavity for the helium, one side of the said cavity being coated with a material which reflects neutrons, but the said cavity also having a portion which does not have that coating. The shell may also comprise other materials in order to seal up the shell layer.

The fuel capsule may be electrically charged and/or may have magnetic properties in order to achieve non-contacting holding function in the reactor. According to an embodiment of the invention, the fuel capsule may be made of a fusible solid material as such. According to an embodiment of the invention, the fuel capsule includes a neutron absorber and reflector material to control the igniter neutron flow in the shell part of the igniter. According to an embodiment of the invention the shell part is made of a material which, when radiated with alpha particles, for instance, generates a lot of neutrons in order to achieve strong neutron radiation directed to a reactant in a space where it exists in the form of a Bose-Einstein condensate so as to bring about nuclear reactions therein. According to an embodiment of the invention the size of the fuel capsule is on the order of a microme- chanical element so as to achieve a capsule having a small mechanical size. The small size is advantageous because the capsule can be held in a non-contacting manner e.g. within a dipole or quadrupole field by means of a sufficient electric charge. To hold the capsule, it is also possible to use some other static and/or dynamic, where applicable, field based on electromagnetism.

According to an embodiment of the invention the fuel capsule is arranged to control the phases of the fuel contained therein, such that the capsule has a part for a solid and/or liquid fuel, which part serves as a storage whence the fuel can be let to gasify, in the same way, for instance, as He-2 tends naturally to do in low temperatures. According to an embodiment of the invention the whole fuel capsule is cooled using e.g. laser cooling and/or magnetic cooling. According to an embodiment of the invention, gasified fuel is cooled in another part of the capsule. In or- der to bring the condensate generated into a certain part of the fuel capsule, the latter includes a part the purpose of which is to concentrate the condensate, according to an embodiment of the invention, in a holder in the fuel capsule with a window which lets neutrons penetrate easily, so as to direct the neutron radiation into the condensate. According to an embodiment of the invention the holder is realized in the form of a funnel at the bottom of which, near its end, the condensate is collected, and through a window which is located at the end of the funnel and which is permeable to neutrons it is possible to direct neutron radiation into the condensate, avoiding an effect on the neutron radiation from the fuel cloud which is about to condense.

Although the invention is described such that an additional cooling can be achieved using a magnetic field after the laser cooling, thus reaching temperatures at which the B-E condensate appears, the invention is not limited as regards the cooling as such. Other cooling methods/arrangements may also be used e.g. as pre-cooling, but also as a boost when approaching the absolute zero.

Figure 5 illustrates an arrangement for controlling a nuclear reaction, placed at a certain part of the reaction volume of the reactor 200 to control the reaction. The control arrangement comprises an ablation means 501 adapted so as to ablate a substance 502 in order to control the nuclear reaction of a fuel used in the reaction through the substance ablated. According to an embodiment of the invention the ablated substance 502 comprises at least a neutron absorber 502A. According to an embodiment of the invention the ablated substance 502 comprises at least a moderator. In spite of how the arrangement is drawn, in an embodiment of the invention the moderator is fed separate from the absorber, however either or both of them as ablated plasma.

According to an embodiment of the invention the arrangement comprises a means 503 for feeding the substance to be ablated so as to change the geometry of a jet of the substance 502, in its ablated form, in order to optimize the said jet to sustain and/or stop the nuclear reaction. The reaction may be a fusion reaction. According to an embodiment of the invention, the ablated substance may also be used for controlling a nuclear reaction taking place in a fission reactor. The means 503 may comprise, in addition to the channel, an electromagnetic means for guiding the substance 502 in the ablated form. According to an embodiment of the invention such means may be a prior-art means for moving plasma by electric and/or magnetic fields. According to an embodiment of the invention the means 503 com- prises an arrangement according to reference [1] for concentrating charged particles/plasma in an electromagnetic tunnel. According to an embodiment of the invention the means 503 includes a part with which the shape of the electric and/or magnetic field can be changed in order to change the shape of, direct, and/or focus a jet of the ablated substance.

Figures 1 to 5 do not show known apparatus and/or equipment for arranging laser cooling, nor apparatus for achieving magnetic cooling, known as such to a person skilled in the art from low temperature laboratories, nor neutron generators known as such to a person skilled in the art, e.g. in connection with the ignition of a hydrogen bomb.

Claims

1. An igniter arrangement, characterized in that the igniter arrangement (100) comprises for igniting a reaction in a reactant

- an electromagnetic holder means (101) to hold, in a non- contacting manner, a reactant (104) in the reaction volume of the igniter,

- a temperature regulating means (102) for controlling the temperature of a reactant (104), and

- a radiation means (103) for radiating a reactant in order to initiate a reaction in said reaction volume defined by the volume in which the non-contacting manner of the electromagnetic holder means (101 ) hold the reactant.

2. The igniter arrangement according to claim 1 , characterized in that in said igniter arrangement the temperature regulating means comprises at least a laser cooling arrangement adapted so as to cool the reactant.

3. The igniter arrangement according to claim 2, characterized in that in said igniter arrangement the temperature regulating means comprises additionally or alternatively a magnetic cooling arrangement adapted so as to cool the reactant.

4. The igniter arrangement according to claim 1 , characterized in that in said igniter arrangement the temperature regulating means is adapted so as to produce a Bose-Einstein condensate of said reactant.

5. The igniter arrangement according to claim 4, characterized in that said igniter arrangement comprises the reactant comprising bosons.

6. The igniter arrangement according to claim 4, characterized in that said igniter arrangement comprises the reactant comprising matter formed of fermions.

7. The igniter arrangement according to claim 6, characterized in that said igniter arrangement comprises the reactant that comprises matter formed of Cooper pairs.

8. The igniter arrangement according to claim 1 , characterized in that in said igniter arrangement said radiation means comprises a means for producing particle radiation and/or for directing it onto the said reactant.

9. The igniter arrangement according to claim 8, characterized in that in said igniter arrangement the particle radiation comprises fermions.

10. The igniter arrangement according to claim 9, characterized in that said igniter arrangement comprises means for adjusting the energy of the said fermions to correspond to the energy needed for producing a thermonuclear reaction in the said reactant.

11. The igniter arrangement according to claim 9, characterized in that said fermions are neutrons, protons, electrons and/or myons.

12. The igniter arrangement according to claim 11 , characterized in that said igniter arrangement comprises an alfa source based on polonium, amerikium and/or californium adapted so as to produce a fermion.

13. The igniter arrangement according to claim 11 , characterized in that in said igniter arrangement includes a reflector and/or refractor for directing neutrons or said other fermions to the reactant.

14. The igniter arrangement according to claim 11 , characterized in that in said igniter arrangement includes a lattice for directing fermions in a focused manner onto the reactant in the form of wave motion.

15. The igniter arrangement according to claim 1 , characterized in that in said igniter arrangement the temperature regulating means comprises a laser cooling apparatus with a turbine scanner.

16. A reactor (200), characterized in that it (200) comprises

- an igniter arrangement (100) according to any one of claims 1 to 15 as arranged to initiate a nuclear reaction in a reactant (104) in the reactor volume,

- a feeding means (201) for feeding nuclear fuel into the said reaction volume,

- a heat exchanger arrangement (202) for transmitting heat out of the reactor volume.

17. The reactor according to claim 16, characterized in that said feeding means of the reactor are arranged to handle said nuclear fuel as a powder.

18. The reactor according to claim 17, characterized in that said feeding means of the reactor are arranged to handle said powder having a monodisperse mode in its particle size distribution.

19. The reactor according to claim 18, characterized in that said reactor comprises said feeding means as arranged so as to feed charged particles into the reactor, the particle size of the charged particles being in accordance with the electrical mobility of the said monodisperse mode.

20. The reactor according to claim 19, characterized in that the charge of the said charged particles is at least equal to the elementary charge or a multiple thereof so defining a first electrical mobility for a first particle size having a certain first charge and so defining a second electrical mobility for a second particle size having a certain second charge so that said first and second electrical mobilities are same, so facilitating means to control the reactor power via the particle size.

21. The reactor according to claim 18, characterized in that the average size of the particles of the said monodisperse mode is between 1 and 100 nm.

22. The reactor according to claim 16, characterized in that the feeding means of said reactor is arranged so as to transfer powder particles in the vicinity of the igniter volume of the igniter arrangement when ignition occurs in the igniter volume, in order to sustain a nuclear reaction.

23. The reactor according to claim 16, characterized in that said reactor comprising said feeding means includes a feeding means for generating plasma from a fuel and/or for feeding plasma into the said reactor volume, said fuel being inserted for use as nuclear fuel.

24. The reactor according to claim 16, characterized in that said reactor further includes an ablation means for feeding a neutron absorber into the reactor volume in order to control neutron concentration in the reactions of the reactor, so to control the reaction via the available neutrons for the nuclear reaction.

25. The reactor according to claim 24, characterized in that it further includes an ablation means for feeding a neutron absorber and/or moderator into the reactor volume in order to control the neutron energy in the reactions of the reactor.

26. The reactor according to claim 25, characterized in that the said moderator is carbon and/or comprises carbon.

27. The reactor according to claim 16, characterized in that said reactor is arranged to be in the form of a ring with a number of sectors so that the reaction in the reactor can be arranged into phases such that a fuel can be fed into a first sector to react in the reactor, the fuel fed in reacts in a second sector, preparations are made in a third sector for the transfer of the reaction from the said second sector to the third sector, in order to sustain a substantially continuous reaction of said fuel.

28. A fuel capsule (300) for storing a reactant of the igniter for a reaction, characterized in that it (300) comprises a cavity (302) containing a reactant as a fuel within a shell (304) impervious to the reactant, and that the fuel is a nuclear fuel to be used in a nuclear reactor or in a reactor according to a claim 16-27.

29. The fuel capsule according to claim 28, characterized in that said reactant is a substance which, when cooled by a temperature regulating means adapted to produce a Bose-Einstein condensate of said reactant, produces a Bose-Einstein condensate.

30. The fuel capsule according to claim 28, characterized in that in said fuel capsule, said shell is made of an optically transparent material in order to facilitate laser cooling.

31. The fuel capsule according to claim 28, characterized in that in said fuel capsule said shell is made of a material permeable to a magnetic field in order to facilitate magnetic cooling.

32. The fuel capsule according to claim 28, characterized in that in said fuel capsule said shell comprises magnetic material adapted so as to achieve a magnetic field in the said cavity in order to facilitate magnetic cooling.

33. The fuel capsule according to claim 28, characterized in that in said fuel capsule said cavity comprises a reflector surface (303) in order to reflect fermions into a reactant in the said cavity.

34. The fuel capsule according to claim 33, characterized in that in said fuel capsule said cavity comprises a spot (301 ) not coated with a reflector surface in order to direct fermions into the said cavity and especially into a reactant therein.

35. The fuel capsule according to claim 34, characterized in that it comprises ⁴He as the reactant.

36. The fuel comprising at least one of the following H, D, T, Li, C, N, O, Be, B, F, Na in the elemental and/or compound form, characterized in that said fuel is a nuclear fuel in powder form, to be used in a nuclear reactor or in a reactor according to a claim 16-27.

37. The fuel according to claim 36, characterized in that said fuel in said powder comprises particle matter that is arranged to be fed with a monodisperse electrical mobility.

38. The fuel according to claim 36, characterized in that said fuel in said powder comprises LiD, LiH, LiT and/or Be.

39. A control arrangement for controlling a nuclear reaction in a certain part of the reaction volume of a reactor's (200) reactor volume, characterized in that the control arrangement comprises an ablation means (501) adapted so as to ablate a substance (502, 502A, 502M) and/or to direct (503) it (502, 502A, 502M) into the reactor (200) for controlling a nuclear reaction of a fuel used in the reaction by means of a flow of matter ablated from the said substance (502, 502A, 502M).

40. The control arrangement according to claim 39, characterized in that substance, that is ablated by the control arrangement comprising ablation means, comprises at least a neutron absorber.

41. The control arrangement according to claim 39, characterized in that said substance ablated comprises optionally or in addition at least a moderator.

42. The control arrangement according to claim 39, characterized in that, for feeding the substance to be ablated, said arrangement comprises a means for changing the geometry of a jet of the ablated substance, adapted so as to optimize the said jet for sustaining and/or stopping the reaction.

43. The control arrangement according to claim 39, characterized in that said nuclear reaction is a fission reaction.

44. The control arrangement according to claim 39, characterized in that said nuclear reaction is a fusion reaction.

45. The control arrangement according to claim 40, characterized in that the neutron absorber comprises a substance that is Hydrogen, Carbon, Beryllium, Boron, Hafnium, Platinum, Xenon, and/or a compound of said at least two substances, a perform of the substance to be released in the reactor or a mixture of the before mentioned.

46. A reactor according to claim 16, characterized in that the reactor is arranged as a tokamak-type-reactor.

47. The reactor according to claim 46, characterized in that it comprises in addition to the infrastructure to handle and/or maintain the plasma-controlling, a control arrangement arranged to feed at least one of the following substances in plasma mode:

- an absorber or a neutron poison to adjust via the concentration a fermion concentration of fermions released in the reaction, and

- nuclear fuel to adjust via the concentration the fuel concentration in certain part of the reactor for maintaining the reaction releasing fermions and/or bosons.

48. The reactor according to claim 47, characterized in that it comprises a neutron poison mantel surrounding the reactors core in which the reactor is occurring.

49. The reactor according to claim 48, characterized in that the neutron poison mantel is at lest in one region in plasma phase surrounding the reactor core arranged to be maintained for protection of the reactor's structures from released neutrons.