WO1993005516A1

WO1993005516A1 - Producing heat from a solute and crystalline host material

Info

Publication number: WO1993005516A1
Application number: PCT/US1992/007135
Authority: WO
Inventors: Joseph L. Waisman
Original assignee: Southern California Edison
Priority date: 1991-08-28
Filing date: 1992-08-24
Publication date: 1993-03-18

Abstract

A system for generating heat at a controllable effective intensity using deuterium as a solute diffused into a host material (21) which has a crystal structure. The host (21) is selectively palladium and absorbs the solute. The combination is maintained at a concentration, temperature, and pressure sufficient to ensure useful heat release.

Description

PRODUCING HEAT FROM A SOLUTE AND CRYSTALLINE HOST MATERIAL

BACKGROUND

The generation of effective useful heat and other energy efficiently and without pollution effect is important to mankind.

This invention relates to the generation of heat and other energy. In particular, it relates to obtaining heat at an intensity which is controllable and effective. More particularly, the invention permits the heat generating source to be small and portable or to be a large or industrialized application.

Heat production by hot fusion of light elements to form heavier elements is known. It is, however, impossible at this time to control the reaction and pro- duce controllable effective heat for industrial or useful application. The process involves reacting one or both of the isotopes of hydrogen, namely, deuterium and tritium by forcing them close at a high temperature pressure to effect fusion.

The generation of excess heat from electrolysis using cells operating at substantially room temperature has become known as "cold fusion." A palladium cathode, deuterium oxide solvent (heavy water D₂0) and lithium deuteroxide (LiOD) solute is used. There is debate whether such cells produce excess heat relative to the power input and excess chemical energy relative to that stored in the reacting materials. European Patent Application 0 395 066 A2 (published October 31, 1990) to Matsushita Electric Industrial Co., Ltd. discloses apparatus for such a process. The contents of that application are incorporated by reference herein. In any event there is no prior art cold fusion technique for obtaining useful, controllable and cost competitive heat output.

Experimental investigations have included the solution of hydrogen and deuterium in metals by elec¬ trolysis to study the detail mechanisms involved in elec¬ trolysis. Other investigations have included the diffu¬ sion of hydrogen from the gas into metals to study the crystalline structural phases in equilibrium at various concentrations of hydrogen, temperatures and pressures. In still other investigations, deuterium has been loaded in titanium under high deuterium gas pressure and cooled to very low temperatures to observe the release of neu¬ trons as the metal is heated. All such investigations are scientific in nature.

No method or system has been proposed for the generation of heat at costs competitive with fossil fuel, by a process using deuterium in a suitable host.

SUMMARY

This invention seeks to provide a system for generating controllable effective heat at a usable and cost competitive intensity level.

By this invention, a method of heat generation is effected by injecting a solute into the host material, the solute being selectively deuterium. The host mate¬ rial is a crystalline structure, selectively palladium, which is capable of absorbing the solute. The host includes a surface in contact with a fluid containing the solute, the solute being at a selected concentration and being maintained at an appropriate temperature for suffi¬ cient time to assure the required diffusion of the solute into the host. The host material can release heat, con- sequent to the introduction of the solute into the host, at a controllable effective intensity.

After the correct amount of deuterium is injected or loaded into the lattice in a mode where the palladium is surrounded by deuterium in a gaseous phase, the resulting body^' is subsequently subjected to appro¬ priate temperatures and effective pressures to produce practical, controllable, cost competitive heat. Alter- natively, the correct amount of deuterium can be loaded in a liquid electrolysis mode, with the palladium being the cathode. In this mode, the body is removed from the electrolysis and subsequently subjected to the appro¬ priate temperatures and effective pressures to produce the practical, controllable, cost competitive heat.

The heat production rate is determined by

J_p/V = K (D/Pd) D μ where D/Pd is the concentration of deuterium; μ is the chemical potential of the deuterium; D is the diffusivity of the deuterium which contains the major temperature relationship; K is a proportionality constant; and V is the volume.

The temperature of the host and the charac¬ teristics of the medium surrounding the host may be controlled effectively such that the system can provide for a one-time type cartridge use, or be a continuous system. The medium may be liquid or gaseous, and the host may take any geometric form suitable to produce the heat with selectively one or more additives to the medium and selectively one or more additives to the host to permit for desired heat generation.

The invention includes the system, method and products for effecting injection of the solute into the host, and the subsequent heat and other energy generation systems, methods and products.

The invention is now further described with reference to the accompanying drawings.

DRAWINGS

Figure 1 is a three dimensional phase diagram of the hydrogen-palladium system. On the upper surface, hydrogen gas co-exists with a hydrogen-palladium solid solution.

Figure 2 is a CPT diagram. Each solid line represents the combinations of C (concentration) and P (pressure) which are in equilibrium when the solid solution is at the T (temperature) marked on the line. Each temperature will have such a line.

Figure 3 shows the intersection of a heat production rate curve, the curved line, and the heat transport line, the straight line. The intersection, shown by the black dot, identifies the steady state temperature and heat production rate.

Figure ^"4 is a cross-sectional schematic of the gas loading apparatus.

Figure 5 is a cross-sectional schematic of the retort of a one-gas heat production system.

Figures 6A and 6B are schematics of a tubular two-gas heat production system. DESCRIPTION

Two methods are provided for injecting deuterium solute into a host material. Although the invention is described with the deuterium, the invention would be equally applicable to operation with the hydrogen isotope tritium.

The host material includes a metal having a crystal lattice structure capable of absorbing a solute contained in a fluid where the solute is deuterium. Then, if the host is exposed to suitable conditions, it is capable of producing heat. For "loading," the deuterium bearing fluid and the host are maintained at an appropriate temperature and the fluid with sufficient driving force for sufficient time for the host to be "filled" with the desired amount of deuterium. Subse¬ quently, the deuterium-bearing host is exposed to the same or other temperatures and sufficient driving force in an appropriate medium so that a reasonably constant rate of heating occurs.

During the loading, either by means of solute bearing gas or electrolysis, the solute is deposited on the host surface at a given concentration. This surface concentration is higher than the concentration of the solute in the body interior. This causes diffusion inward, thus progressively "filling" the body of the host with the solute. The surface concentration depends on the controllable driving force, namely, the gas pressure or the electrode potential for gas loading and electroly¬ sis loading, respectively. The driving force for heat production is discussed subsequently.

Although other metals may also be appropriate, the preferred hosts are based on palladium, titanium, or zirconium. They may be commercially pure, or contain other elements alloyed with the host to improve proper¬ ties or reduce cost.

In the loading process, the medium bearing the deuterium can also contain other materials for specific purposes. For the gas loading process, inert or active gases may be added to the medium to adjust the flow or pressure, or to react with the host surface. For the electrolysis loading process^", the electrolyte composition contains a number of chemical species to obtain the results.

In addition, for both loading processes, addi- tions such as lithium or other metals with low atomic number may be required before or during the loading process. The atomic number should be lower than 5, and selectively, the elements could be Sodium or Beryllium. Such additions may be solutes, or form part of the lattice, and may enhance the heating effect or control the emission of undesired by-products.

Either loading process should be preceded by cleaning the surface using a combination of mechanical, chemical and electrochemical methods. In the gas-loading process, most of the cleaning can be performed by evacu¬ ating and heating, combined with exposure to hydrogen or deuterium at an elevated temperature.

For heat production from a loaded palladium host, temperatures in the range of room temperature, namely, about 25°C to about 500°C are employed, and mechanical pressures from a fraction of an atmosphere, for instance, 0.1 atmospheres to as high a mechanical pressure as are practical to achieve safely will be used, for instance, 1,000 atmospheres. For other metals, the ranges of temperatures and pressures vary. Thus, for titanium and zirconium, the temperature is a range between about 25°C and 1,750°C.

In one form, the host is a solid body which is suitably encased, and can be stored prior to use. This can be portable for domestic use, large for industrial use and of intermediate sizes for other uses.

In yet other forms, the system can be one where palladium core material is provided and deuterium bearing fluid is permitted to pass about the palladium metal host.

In one such form, a deuterium-bearing gas is circulated past the host surface and serves the dual purpose of supplying fuel, and removing the heat produced by the host. In another such form, a deuterium-bearing gas is used primarily to supply the fuel to the core, and another heat exchange fluid removes the heat. The two gases are separated by the host material in a manner described below.

Actual data and estimates on the cost of producing heat using fossil fuel are generally grouped into fuel costs, operating costs and capital costs. The fuel cost is the quantity of fuel consumed during burning, multiplied by its cost per unit heat. The latter quantity, for example, might be expressed as dollars per joule.

The cost of deuterium fuel "consumed" per unit of heat produced is similar. For a nuclear reaction, cost is a fraction of the cost of the fossil fuel. For deuterium-in-host produced heat, other costs generally included as capital, overwhelm the cost of deuterium consumed. Such "other costs" do not depend simply on the amount of fuel consumed; they depend on the rate at which heat is generated per quantity of deuterium and host.

An illustration of "other costs" is set out. Consider a deuterium-in-host heat producing industrial plant, using a palladium host and designed to produce heat at a give rate, say 100 megawatts, and using a continuous process. Using the presented principles, a low or a high intensity heat per unit host volume or per unit weight of deuterium could be produced.

For low intensity heat per host volume, more palladium is required to produce heat at the fixed rate. Low intensity heat also requires more deuterium which is not "consumed" and converted to heat. These two costs may be high and are paid for over the useful life of the plant. Similar logic applies to the solid fuel cartridge system.

These costs increase rapidly as the power per unit volume of the host or per unit weight of deuterium decrease. An estimate of the "other costs" involved for a range of power intensities can be made. The power intensities are expressed as watts per gram of deuterium. The total cost per heat unit is then estimated as a measure of commercial usefulness of each rate for a range of power intensities.

The rate of nuclear events is frequently expressed as "events per deuterium pair per second." For convenient comparison, a selection of the unit of power is made to be watts per deuterium pair. This is the watts per gram of deuterium, divided by the deuterium pairs per gram.

It is believed that controllable, reasonably constant heat output can be obtained in the range of 5 x 10^"24 to 5 x 10^"18 Watts per deuterium pair in the host. Cost estimates show that the upper part of this range, from 5 x 10^"20 Watts per deuterium pair and up, are cost competitive to fossil fuels.

While the exact scientific mechanism for which the energy output from the deuterium collisions are not understood at this time, there is good reason to believe that the heat output rate will be consistent with the following principles. These principals form the basis for immediate applications prior to an understanding of the detail mechanism of the reaction or reactions.

PRECURSOR SELECTIONS

The purpose of all embodiments of this inven¬ tion is to produce heat for use. The deuterium is a fuel, and the heat is produced when the deuterium is introduced into a metal crystal lattice and collides with itself or with other elements of the lattice. The changes that occur during the collisions produce heat with an accompanying slight mass loss.

For the heat to be useful and safe, three groups of decisions are made.

(a) The materials, their size and shape.

(b) A combination of "conditions" to apply to the body, and a determination of the quantity of heat which will be produced by these conditions. The controllable conditions are: the temperature, the concentration of deuterium in the crystal lattice, and the internal "pressure" of the deuterium resident in the lattice. The internal "pressure" is properly called its "activity" in thermodynamic parlance. Except for transi- tion periods after a change, the activity of the deute¬ rium inside the metal is balanced by, namely, is in equilibrium with, the activity of the deuterium outside the metal.

(c) The surroundings of the heat pro¬ ducing deuterium-in-metal is such that heat is trans¬ ported from the metal to the surroundings, in a manner so that a reasonably constant temperature gradient and rate of heat flow is maintained.

Balancing the heat production and transport in Step (c) is necessary since the device can overheat and melt if more heat is supplied than is removed. Alter¬ natively, the device could cool below the desired opera¬ ting temperature. The device would then become less useful if less heat is removed relative to the energy supplied. The heat removal is controlled by the nature of the medium in contact with the metal, its temperature and its velocity. The medium may be gaseous or liquid, stationary or moving. Its temperature may be at or above room temperature.

THE HEAT PRODUCTION EQUATION

There are three related phenomena in which deuterium in metal solution can participate: diffusion, chemical reactions, and nuclear reactions. The three are closely related in that they will occur during the high frequency jumping of the deuterium within the lattice. The important features of the jump are its frequency, and the force in each jump. The "force" for chemical reactions has been shown by thermodynamic theory and experiment to be the change in free energy which occurs per unit reaction. To a close approximation this can be represented by a quantity called in thermodynamics the "chemical potential" of the deuterium in the solution. The chemical .potential is a f nction of the temperature and the activity of deuterium.

When a deuterium particle is jumping, it does not know whether the jump is to result simply in movement (diffusion) , in a collision-caused reaction of electrons (chemical reaction) , or in a collision-caused reaction of nuclei (nuclear reaction) . The rate of each of the three types of event is proportional to the jump frequency, and the rate of chemical and nuclear reactions are also proportional to the jump force.

Another factor, the quantity of deuterium which is in the lattice, should be considered. The greater the quantity, the greater the number of candidates for the reaction, and the higher the rate.

A combination of the above statements in mathematical form is:

J_p = K' Md v μ (1) where J is the rate of heat production, in watts, the Md is the mass of deuterium dissolved in the body, in grams, the v is the frequency of jumping per second, and the μ is the chemical potential of the deuterium in the solu¬ tion in joules per gram mole. The K' is a constant of proportionality which is determined experimentally for nuclear reactions and for each host metal.

To permit calculations, two substitutions are made. The mass of deuterium, Md is replaced with its equivalent, concentration X volume, expressing the con¬ centration in the atomic ratio of deuterium to palladium, D/Pd and denoting the volume by V.

The second substitution is the diffusivity D for the frequency. It is proportional to the frequency of jumping. Thus, available diffusivity data from the literature is used. The D is used in the equation below for two different definitions, D for diffusivity and D for deuterium. The D for diffusivity is underlined to identify it. The K' in equation 1 becomes a dimensional constant K to accommodate the substitutions. Equation (1) now becomes:

J_p/V = K (D/Pd) D μ (2) Equation (2) is the Heat Production Equation. It contains within it the concentration of deuterium (D/Pd) , the equilibrium deuterium gas pressure (in the μ) , and the temperature (in the I) and in the μ ) . These are the three controllable properties, namely, the CPT properties.

LIMITS TO CPT SELECTION

There are limits to the arbitrary selection of any C, P and T. These limits are of two types.

First, deuterium dissolves in metals over a specific temperature range, and in this range the solubility is limited. These limits are much different for different metals. These are illustrated for the palladium-hydrogen system. The limits are similar for ordinary hydrogen or the deuterium isotope of hydrogen.

Figure 1, taken from the literature, shows these limits in a three dimensional portrayal of the combinations of C, P and T which can be obtained. The doubly curved surface in Figure 1, which are cross- hatched 10 and indicated to be defined between numerals 1, 2, 3 and 4 indicates the dividing line between gaseous hydrogen and solid Pd-H solution. Combinations above as indicated by arrow 6 of the surface 10 or to the right as indicated by arrow 7 of this surface 10 are gaseous hydrogen. Combinations as indicated by arrow 8, the cross-hatch 10, or to the left as indicated by arrow 9 of this surface 10 are solid Pd-H solution. Combinations on cross-hatched surface 10 are those for which the gas and the solid can co-exist. These combinations defined by the cross-hatched surface 10 are used for the host sur¬ face during loading. Combinations on surface 10 or below surface 10 as indicated by arrow 8 are used for the heat production.

By making a calculation for a number of candi¬ date CPT combinations, using equation (2) their heat production rates can be determined. The higher the heat production rate, the lower the cost per energy unit. However, too high a rate may be difficult to keep stable, or have too short a life to be practical. Each decision is a design tradeoff.

The second kind of limit is in the relationship between the C, P and T. By selecting any two of them, the third is automatically determined. Figure 2, a CPT diagram from the literature, shows two of a family of constant temperature curves.

The scales are H/Pd (the hydrogen concentra¬ tion) and P, the gas pressure. While this diagram is for hydrogen, the deuterium diagram will be similar. It is apparent that if the temperature is fixed, one is on a single solid line of the family. If the concentration then is also fixed, the pressure is automatically determined.

AN EXAMPLE OF THE DECISION MAKING

Palladium is selected as the host. The size and shape is a 0.4 cm. diameter circular rod, 1.25 cm. long. The rod is filled with deuterium to a D-Pd atomic ratio of 0.7 which is within the Figure 1 limits as shown by numeral 5 in Figure 1. In operation, the body is sur- rounded with water having a bulk temperature, namely, not near or adjacent the body, of 25°C. Assume that an ex¬ perimentally determined K in equation (2) is 1.05 X 10^"18 in the units shown. So far, except for adhering to the Figure 1 limits, the choices are arbitrary.

The values of P and T must now be determined to calculate the heating production rate per unit volume, _/V by Equation (2) . At a series of temperatures, the pressure P, using a CPT diagram like Figure 2, is deter¬ mined.

For use in making numerical calculations using equation (2) , the following two relationships from diffu¬ sion technology and thermodynamics respectively, for the diffusivity and the Chemical Potential of deuterium in palladium is added: D = Do exp (-Q/RT) (3) where Do is 0.0095, in cm²/sec, Q is the activation energy, 6500 calories per mole, R is the universal gas constant in calories per mole per degree Kelvin, and T is the temperature in degrees Kelvin. The D is also in cm²/sec. μ = (2.3026 2JR T Log(Pma) (4) where the Pma is the pressure of deuterium gas in equilibrium with the body in milli-atmospheres, and the Log is to the base 10. Standard pressure is one milli- atmosphere.

The equation (2) calculations show the rela¬ tionship between the temperature and heating rate as shown in the curve 12 of Figure 3. The curve rises from left to right.

For a steady state, the rate of heat production per unit volume is equal to the heat transported away from the body per the same unit volume.

Almost all the heat transported is by the convection mechanism and the rate of heat transport vs. temperature is calculated using a form of Newton's law of cooling:

Jt/V = h (S/V) (Tw-Tb) (5)

Jt is the rate of heat being transported in watts, S and V are the surface area and bulk volume of the body (cm² and cm³) , and Tw and Tb are the temperature of the body wall and the bulk^" of fluid in Centigrade. The h is an experimentally determined constant for the type of body surface and fluid, called the heat transfer coefficient. From experiments, h=0.1 is determined for the units used in the equation.

Everything is now known but the Jt and the Tw. Equation (5) is the linear relation between the two unknowns, the straight line 13 in Figure 3.

The condition for a stable steady state is that J /V (from equation 2)= Jt/V (from equation 5) . This is true at the point where the heat production line and the heat transport line cross at numeral 14 on Figure 3. The stable temperature for the body will be 47°C and the heat being produced will be 21.5 watts per cm³. The steps (a), (b) and (c) previously outlined are complete. If this is not satisfactory, the process is iterated. This proce- dure permits for the rate of heat production to be at a controllable effective intensity.

Higher temperatures and pressures than those used in this example produce energy at costs increasingly competitive with fossil fuels.

TIME OF LOADING

Conventional calculations understate the time required for complete loading by a hydrogen or deuterium solute by 1 or 2 orders of magnitude. This is explained by examining the usual method used for calculations, known as "Fick's Law." This law states that if one had a pattern of differing solute concentrations in three dimensional space, there would be a movement of mass (diffusion) in the direction of the downhill concentra- tion gradient. The rate of diffusion at any location would be proportional to the concentration gradient at that location.

For illustrative purposes, we examine a parti- cular concentration pattern. " Consider that the pattern were such that the gradient is in the same direction at all locations called the X direction; the diffusion would occur only in the X direction. This is one-dimensional diffusion. Fick's Law for this condition is F = - D (dC/dX) . F is the diffusion flux in grams per square cm. per second; C is the concentration in grams per cubic cm.; X is the distance in the X direction in cm. The D is the proportionality constant called the diffusivity.

Fick's equation, which is a differential equation, when solved for a rod which has almost been "filled" with solute to a uniform concentration using a fixed concentration at the body surface gives the solu¬ tion: time in seconds = 0.082 d²/D where d is the rod diameter.

It is not realized, however, that Fick's Law is a special case of a more general equation. Fick's Law is valid only for a single phase solid, and even then is rigorous only for a dilute solute solution. This is far from true for a Pd-D solid solution. At normal pres¬ sures, it is a 2-phase solution, and a solute-rich phase. Hence, the gross understatement of diffusion time by Fick's Law. A time is selected, allowing a long period when the heating rate is rising slowly. LATTICE PUMPING

For different embodiments of this invention, it should often be desirable to move deuterium within the host, after the host is loaded and is producing heat. It has been shown for other purposes, that such internal movements can be realized by designing the host lattice with suitable permanent internal energy gradients. This action is termed "lattice pumping."

Such internal gradients may be part of the host fabrication, and consist of gradients in temperature, host composition, or built-in stress. A composition gradient can be made effectively permanent by employing alloying elements whose diffusion rate is negligible at the heat producing temperature gradient in the host.

Lattice pumping should be useful for extending the useful life of the loaded host or increasing the rate of heat production.

An example of lattice-pumping is given below for a two-gas system.

More specific details of the different embodi¬ ments of the invention are now described.

Solid Fuel Cartridges Produced bv a Batch Process

This embodiment consists of preparing and using a solid cartridge which contains deuterium in solution in the solid. It is intended for uses where simplicity and convenience of the process is important. The user schedules the active life as needed. The process is considered in 3 parts; the loading, the storage, and the heat production. The solid material making up the car¬ tridge (the host) is a metal with appropriate character- istics for absorbing the deuterium on its surface, and then permitting the deuterium to penetrate the interior so that it may be approximately "filled" to a large deuterium capacity.

The host is reasonably pure or alloyed palla¬ dium, titanium, zirconium or other metals having the appropriate properties. The host may have an alloyed surface layer, or be alloyed in depth with a third metal, such as lithium, to enhance the heat production.

The host may be in a variety of shapes such as circular rods, disks, blocks, wires, plates, flat or shaped sheets, or a configuration of multiple bodies, or it may consist of an aggregate of finely divided solids or be powderized.

Loading

The cartridge is injected or loaded with deuterium using either an electrolysis method or using deuterium containing gas at an appropriate concentration, partial pressure, temperature, and time. Appropriate surface cleaning precedes the operation. The time period of loading is longer than conventionally calculated for diffusion using the Fick's Law predictions. This is determined by experiment as previously described.

Figure 4 is a schematic showing the principal features of apparatus for gas loading. The retort 22 is gas tight and contains the host with solute 21. Pump means 26 for evacuation and pressure retention are pro¬ vided to the retort 22. Furnace means 23 for heating is located strategically about the retort 22. Temperature sensors 29 and instruments 28 for measuring pressure are provided. A piping system 20 is provided for solute in the gas phase to enter the retort 22 as indicated by arrow 24. Gas exit is shown by arrow 25. Valves 27 are used as necessary. Some of the equipment described may be deleted if not required for the conditions selected. Surface cleaning may be by a combination of evacuation and heating. There are cleansing means 30 figuratively shown for cleaning the host 21 surface as required.

The actual equipment used may differ from that illustrated in Figure 4, however, it does provide the same functions. For example,^' the gas loading may be in batches, each batch followed by a timed penetration or diffusion process. Alternatively, the gas may be loaded continuously and/or the body may be in motion. Heating to the appropriate temperature may be performed by a furnace, electrical resistance, induction or other means.

The gas loading process is simpler than elec¬ trolysis, has fewer variables to control, and can be more easily adapted to the entire range of CPT conditions.

Figure 1 has a gas pressure scale appro¬ priate for use with gas loading and for heat production in a deuterium gas environment. For electrolytic loading, the gas pressure scale is replaced with an electrode voltage scale. This is illustrated diagram- matically in Figure 1. The equivalent electrode voltage for each pressure is defined by the following equation: 2FE = -4.186 RT (LnP) . E is the electrode voltage com¬ pared to a standard Platinum/hydrogen electrode at a standard pressure of one atmosphere. P is the equivalent gas-loading pressure in atmospheres for a standard state of one atmosphere. The minus sign indicates that the electrode potential goes down, i.e., becomes more cathodic, as pressure goes up.

This equation states that the amount of work done by the electrolytic cell in injecting a mole of H into the host is the same as the amount of work done by the gas in performing the same work. The lefthand side of the equation is twice the quantity of work, in Joules, done by the electrolytic cell. The right side is twice the same amount of work performed by the gas expressed in terms of the gas properties. F is a Faraday, 96,500 coulombs; R is the gas constant, calories per mole per degrees K; T is the temperature in degrees K; and 4.186 is a unit conversion factor, the number of Joules equal to a gram calorie.

When the loading is completed, a coating imper¬ vious to deuterium is applied. This permits the car¬ tridge to be removed from the loading chamber or storage and use without losing the deuterium.

The cartridge may be placed in the heat pro¬ duction apparatus immediately after loading without an impervious coating. The transfer is made quickly, and the heat production apparatus is quickly filled with deuterium gas at an appropriate pressure.

Storage

For a palladium host, storage at -50°C or lower reduces the rates of heat production and the rate of deuterium loss by outward diffusion to negligible values. Storage can be in any convenient cooled chamber.

Use for Heat Production

The cartridge is placed in a chamber where the heat produced is transported to the surrounding fluid and then directly to the end use or intermediate heat exchangers. The cartridge is activated by heating it to the design operating temperature, somewhat as a fossil fuel is heated to its burning temperature. The heat production begins and continues to increase until the heat production is balanced by the heat removed, as previously described. Use continues at essentially a steady state.

Heat is produced with gradually decreasing intensity as the reacted fuel is removed from the reaction. Eventually the fuel reaches its economic life, and can be removed for recharging or recycling. The economic life can be varied over a wide range by choice of the operating CPT conditions.

The solid cartridge is adaptable to both small and large users, with appropriate design for each.

Continuous One-Gas System

The CPT operating conditions are determined using the methods previously described. For this system the loading and heat production are performed continuous¬ ly in the same chamber. A schematic sketch of a chamber is shown in Figure 5. In Figure 5, 33 is the core con¬ taining the host and absorbed solute, 35 is insulation, 34 is a steel container, 31 and 32 are the gas-in and gas-out tubes. The metallic "host materials" of the same types as the previous embodiment are used to form the "core." It is configured so as to permit gas to pene¬ trate with reasonable uniformity to all host surfaces.

The dimensions of the smallest elements are selected to provide the ratio of surface area to mass required by the operating conditions, as has previously been described. The core consists of a grid of wire meshes, a composite structure of mounted balls or mounted powders, or may be of many other configurations. It is designed so that the stresses and distortion which are present in the host structure can be minimized. The supporting structure may be of strong, non-distorting materials.

After placing the core, hot gas or other suitable means is used to heat the core to the design operating temperature. The hot gas may be inert, or may be deuterium. As the temperature reaches the operating range, deuterium gas is introduced at the pressure required for the design heat output rate. The deuterium penetrates the host by diffusion and after an appropriate concentration of deuterium is reached within the hosts, heating occurs. The temperature of the entering gas is then decreased until a steady state is achieved. In this condition, cool gas enters and hot gas leaves. The hot gas is used directly or after heating another medium in heat exchangers.

While a core is expected to have a long life, its life may be limited by two phenomena. One is the progressive distortions which will cause inefficiency because of uneven gas penetration and resulting hot and cold zones. Proper design should minimize this problem. Another is the accumulation of impurities and reaction products in the host and in the circulating deuterium gas which decreases its activity with time. A gas purifica¬ tion process can extend the gas life to long times. Replacement of the host periodically may be required.

The one-gas continuous process can have two classes of systems. One is a low temperature system based on palladium. This operates below 500°C due to solubility limits in the palladium as shown in Figure 1. The other class is not limited to this range and uses other metals which dissolve large amounts of deuterium at much higher temperatures. Probable hosts are titanium and zirconium and their alloys, and temperatures of 800°C to just below the melting point are quite likely. These systems use hosts with high surface to volume ratios and high velocity fluids. The higher temperature heat is valuable in certain industries.

This continuous process should produce energy at a lower cost than the solid cartridge embodiment. In the solid cartridge, at the end of its useful life the host is recharged or remelted, and the unused deuterium is significant. These are high costs to be amortized over the active life. In contrast, the continuous pro¬ cess uses the host material for a longer time, and the major deuterium loss will be during startup and shutdown. These costs would be lower and distributed over a longer life.

This process requires a larger capital invest¬ ment and higher maintenance costs than the solid car¬ tridge, and requires skilled operators and a technical staff. It is compatible with medium and large companies accustomed to operature industrial processes.

A Continuous Two-Gas System

This is also a long life systems which has many design and operational features in common with the one gas system. It is also expected to be a low cost energy producer. The host configuration is a solid sheath separating the operating gas, deuterium, from the heat exchange medium. The latter medium is any of a large number of available liquid or gaseous media. A tubular shape of the host material for retaining the deuterium gas is practical. Figures 6A and 6B are schematic sketches of such an apparatus. The tubular host con¬ taining solute is in a tube 42, the wall of which is indicated by numeral 48. The deuterium bearing gas enters at 41, circulates through the host tubes 42, and leaves the retort at 43. The heat exchange medium enters at 44, circulates in the volume 46 of the chamber outside the host tubes 42 and leaves the retort at 45. The external shell and insulation is marked 47. The heat exchange medium could be gaseous or liquid.

The deuterium gas would be circulated inside the host tubes, arid the heat-exchange medium outside the tubes. The heat-exchange medium is maintained at a low partial pressure of deuterium, and the deuterium gas at a higher pressure. This causes- a sharp concentration gradient of deuterium dissolved in the tube wall. The gradient, in turn, provides for a continuous flow of deuterium through the tube wall by a diffusion process. As in the other systems, the operating temperature is determined by the rate of heat production in the tube wall, and heat removal by both fluids.

The movement of deuterium through the tube can also be assisted by varying the composition of the host through the tube wall. The change in host composition is selected so that the inner surface of the tube wall has a higher chemical potential than the outer surf ce of the tube wall. The effect will be an increasing flow rate of deuterium through the wall. This effect is called lattice-pumping.

This type of composition gradient can b pro¬ duced by welding a composite wall of two compositions of a third alloy element, followed by a high temperature diffusion treatment. The host and deuterium are the other two elements. ^•

During startup hot gas is circulated inside the tube and hot liquid or gas outside the tube. As the tube wall is filled with deuterium and "ignited", a steady state of heat production and removal is achieved. At steady state, cool deuterium enters the tube, and hot deuterium leaves. Cool heat-exchange medium enters and hot fluid leaves. A purification process may be required for both fluids. The deuterium would have impurities and reaction products removed, and the heat-exchange medium would have impurities, reaction products removed and deuterium content reduced. The process operates over a wide range of composition.

The position of the deuterium gas and heat exchange fluid may be reversed from that indicated. There are advantages to each arrangement. A higher pressure outside the tubes produces a predominantly compressive stress in the tube and a consequent longer life if embrittlement occurs. For designs where main- tenance of the tube shape is all important, a higher inside pressure would be helpful.

The life of a typical two gas system is more limited than the one-gas system, since the stress on the tube may cause distortions. Both continuous systems should have the previously stated economic advantages over the solid cartridge system. Like the one gas system, the two gas system is compatible with the moderate or large industrial firm.

The two gas continuous system can operate in low and high temperature classes as described for the one gas system.

Many other examples of the invention exist each differing from other in matters of detail only. It should be understood that the present invention sets out a major new technology for generation of effective energy from the interaction of appropriate solute materials containing an isotope of hydrogen with suitably struc¬ tured host materials. The scope of the invention is to be determined solely by the appended claims.

Claims

CLAIMS :

1. A method of injecting a solute contained in a loading fluid into a host material, the solute being selectively deuterium or tritium, selecting the host material to include a crystalline structure capable of absorbing the solute, maintaining the solute containing loading fluid and the host at a concentration, tempera¬ ture and pressure for a time period sufficient to insure diffusion into the host material, and enabling the host material to produce heat consequent to the introduction of the solute into the host material, the rate of heat production being at a controllable, effective intensity.

2. A method as claimed in claim 1 wherein the solute is deuterium, is introduced from a gaseous phase and is soluble relative to the host material, the host material being palladium, and wherein the temperature is in a range between about 25°C and about 500°C and wherein the pressure is in a range between about 0.1 atmospheres to about 1,000 atmosphere.

3. A method as claimed in claim 1 wherein the host is a lattice, the lattice including selectively at least in part palladium, titanium or zirconium.

4. A method as claimed in claim 1 wherein the rate of heat production is determined by

J/V = K (D/Pd) D μ where D/Pd is the concentration of a deuterium solute; μ is the chemical potential of deuterium solute; D is the diffusivity which contains a temperature effect; K is a proportionality constant; V is the host volume and J is the rate of heat production.

5. A method as claimed in claim 1 wherein the temperature is maintained substantially constant in rela- tion to the selection of the size and a shape of the host, and of the composition and velocity of a surround¬ ing fluid, whereby heat is removed from the host at substantially the same rate as heat is produced.

6. A method as claimed in claim 1 including cleaning an outside surface of the host material thereby to maintain the host material permeable to the solute, the cleansing being selectively effected by chemical action or vacuum heating.

7. A method as claimed in claim 1 wherein diffusion of the solute into the host is effected at a temperature range of about 25°C to about 500°C and a pressure range of about 0.1 atmosphere to about 1,000 atmospheres with a concentration of the solute being about a D/Pd of about 0.4 to about 1.2, the solute being deuterium, and wherein the host material includes palladium.

8. A method as claimed in claim 1 wherein the diffusion is effected for a period determined by measuring the actual solute concentration in the host, the time period being selectively substantially longer than the time period determined by Fick's Law.

9. A method as claimed in claim 1 wherein the production release of heat is effected by heating the solute containing host material to a predetermined temperature, wherein with a host containing palladium, the temperature is in a range between about 25°C and about 500°C, and for a host containing titanium or zirconium, the temperature is in a range between about 25°C and about 1,750°C.

10. A method as claimed in claim 1 wherein the host includes the addition of selected elements thereby to increase the rate of heat production, and wherein when the host material includes palladium, the selected ele¬ ments are at least one of lithium, sodium, beryllium or other elements with a low atomic number.

11. A method as claimed in claim 1 wherein a host is first loaded with solute, selectively is stored in a temperature level wherein there is essentially no heat production, and subsequently is subjected to conditions for producing heat.

12. A method as^" claimed in claim 1 including encasing the host material and solute, the encasement effectively preventing diffusion of the solute outside the encasement, and whereby the heat is transmitted through the encasement.

13. A method as claimed in claim 1 including inhibiting the outward diffusion of the solute by applying an impervious coating to the host material diffused with the solute, and selectively inhibiting both the outward di fusion and the heat production within the solute containing host by cooling the host to a suitable temperature.

14. A method as claimed in claim 1 including removing reaction products from the host caused by the reaction of the deuterium with the host and replacing the reaction products with deuterium whereby the heat production rate is maintained substantially constant.

15. A method as claimed in claim 1 including removing heat produced by the host at a desired rate by using a selected host size and shape, the selected shape being at least one of a sphere, cube, cylindrical rod, sheet or plate, and a selected surface to volume ratio and the size being selectively powderized.

16. A method as claimed in claim 1 wherein the host material is located in a reactor retort and provides an effective surface to volume ratio of the host material and wherein the solute is permitted to pass through the reactor in a liquid or gas phase and wherein the flow rate of liquid or gas passing through the reactor is variable, thereby to control and maintain the effective intensity of heat production.

17. A method as claimed in claim 1 wherein the host is configured to separate a reactor into separate chambers, a first chamber providing a fluid supply of solute to the host, and a second chamber containing fluid, the fluid removing reaction products and heat from the host and the heat production being in a substantially steady state.

18. A method as claimed in claim 1 including moving solute within the host during the heat production, the host including energy gradients, the energy gradients including selective gradients in host composition, temperature or host stress.

19. Apparatus comprising a solute containing fluid, the solute being selectively deuterium or tritium, a host material having a crystalline structure capable of absorbing the solute, means for maintaining the solute containing fluid and the host at a concentration, temperature, pressure and time sufficient to insure diffusion into the host material, and means for enabling the host material to produce heat consequent to the introduction of the solute into the host material, the rate of heat production being at a controllable, effective intensity.

20. Apparatus as claimed in claim 18 wherein the solute containing fluid includes deuterium in a gaseous phase and the deuterium is soluble relative to the host material, the host material being palladium, and wherein the temperature is in a range between about 25°C and about 500°C and wherein the pressure is in a range between about 0.1 atmospheres to about 1,000 atmospheres.

21. Apparatus as claimed in claim 18 wherein the host is a lattice, the lattice including selectively at least one of palladium, titanium or zirconium.

22. Apparatus as claimed in claim 18 wherein the rate of heat production is determined by

J/V = K (D/Pd) D μ where D/Pd is the concentration of a deuterium solute; μ is its chemical potential; p_ is the diffusivity which contains a temperature effect; K is a proportionality constant; V is the host volume; and J is the rate of heat production.

23. Apparatus as claimed in claim 18 including means to maintain the temperature substantially constant by selecting the size and shape of the host, and means for varying and controlling the composition and velocity of the surrounding fluid, so that heat is removed from the host at the same rate it is produced.

24. Apparatus as claimed in claim 18 including means for cleaning an outside surface of the host material thereby to maintain the host material permeable to the solute, the cleansing being selectively effected by chemical action or vacuum heating.

25. Apparatus as claimed in claim 18 including means for diffusion of the solute into the host at a temperature range of about 25°C to about 500°C and a pressure range of about 0.1 atmosphere to about 1,000 atmospheres with a concentration of the solute being about a D/Pd of 0.4 to 1.2, the solute being deuterium, and wherein the host material includes palladium.

26. Apparatus as claimed in claim 18 including sensors or testing means for determining the loading or diffusion time, and means for measuring the solute concentration in the host.

27. Apparatus as claimed in claim 18 including means for affecting the production of heat by heating the solute containing host material to a predetermined temperature, the temperature being in a range between about 25°C to about 500°C when the host includes palla¬ dium, and in a range between about 25^βC and about 1,750°C when the host contains titanium or zirconium.

28. Apparatus as claimed in claim 18 wherein the host includes the addition of selected elements thereby to increase the host heating rate, and when the host material includes palladium, the elements added to the host material are at least selectively one of lithium, sodium or beryllium, or other elements with a low atomic number.

29. Apparatus as claimed in claim 18 including an encasement for the host material and solute, the encasement effectively preventing diffusion of the solute outside the encasement, and whereby the heat is trans¬ mitted through the encasement.

30. Apparatus as claimed in claim 18 including means for inhibiting the outward diffusion of the solute by an impervious coating to the host diffused with the solute, and cooling means for selectively inhibiting both the outward diffusion and the heat production within the solute containing host.

31. Apparatus as claimed in claim 18 including means for effecting the removal of reaction products from the host and means for effecting the replacement with deuterium.

32. Apparatus as claimed in claim 18 wherein the host is selectively one or more spheres, cubes, cylindrical rods, sheets or plates having a selectively different surface to volume ratio or is selectively powderized. - -

33. Apparatus as claimed in claim 18 including means for locating the host material in a reactor retort and provides an effective surface to volume ratio of the host material and means for permitting the solute con¬ taining fluid to pass through the reactor in a liquid or gas phase and wherein the flow rate of liquid or gas passing through the reactor is variable thereby to con¬ trol and maintain the effective controllable intensity of heat production.

34. Apparatus as claimed in claim 18 wherein the host material is configured to separate a reactor into separate chambers, a first chamber providing a fluid supply of solute to the host, and a second chamber con¬ taining another fluid which serves both to remove re¬ action products and heat from the host and wherein the heat is produced in a substantially steady state.

35. Apparatus as claimed in claim 18 including means for moving the solute within the host during the heat production, and including energy gradients in the host, the energy gradients including selective gradients in host composition, temperature or host stress.