Fluid heater -- US9115913

Extracted document text. Layout, formulas and symbols may not survive extraction; consult the preserved PDF for the original presentation.

Text extraction covers 8 pages, including 8 transcribed by optical character recognition.

Page 1

US009115913B1

a2) United States Patent (10) Patent No.: US 9,115,913 B1
Rossi (45) Date of Patent: Aug. 25, 2015
(54) FLUID HEATER 2004/0013585 Al* 1/2004 Whyatt et al. . 422/189
2004/0065314 Al* 4/2004 Layer et al . 126/263.03
(75) Inventor: Andrea Rossi, Miami Beach, FL (US) 2010/0251694 Al* 10/2010 Hugus et al. 60/253
2010/0252023 Al* 10/2010 Coffey et al. . 126/263.01
(73) Assignee: Leonardo Corporation, Miami Beach, 2011/0005506 Al 1/2011 Rossi
FL (US
(08) FOREIGN PATENT DOCUMENTS
(*) Notice: — Subject to any disclaimer, the term of this ,
patent is extended or adjusted under 35 EP 2341119 9/2013
U.S.C. 154(b) by 609 days. » cited by examiner
(21) Appl. No. 13/420,109
») Filed Mar. 14,2012 Primary Examiner — Alissa Tompkins
(22) Fi “= Assistant Examiner — John Bargero
(51) Int. Cl. (74) Attorney, Agent, or Firm — Occhiuti & Rohlicek LLP
F245 1/00 (2006.01)
(52) US.CL
CPC . vee F24J 1/00 (2013.01) 57) ABSTRACT
(8) Field of Classification Seareh vow 122/16.1, 21 An apparatus for heating fluid includes a tank for holding

(56)

See application file for complete search history.
References Cited
U.S. PATENT DOCUMENTS.
12/1921 Koetschet

4/1963 Hudson .......
11/2003 Abe

1,400,959 A
3,083,526 A *
6,641,795 B2

+++ 60/220

fluid to be heated, and a fuel wafer in fluid communication
with the fluid. The fuel water includes a fuel mixture includ-
ing reagents and a catalyst, and an electrical resistor or other
heat source in thermal communication with the fuel mixture
and the catalyst.

10 Claims, 5 Drawing Sheets

14

Page 2

U.S. Patent Aug. 25,2015 Sheet 1 of 5 US 9,115,913 B1

10
/
12

16
( _

U ™"€~
—_—
»[) -@z
| ~ (=~

<— =

18

FIG. 1

Page 3

U.S. Patent Aug. 25,2015 Sheet 2 of 5 US 9,115,913 B1

33

FIG. 2

Page 4

U.S. Patent Aug. 25,2015 Sheet 3 of 5 US 9,115,913 B1

FIG. 3

Page 5

U.S. Patent Aug. 25,2015 Sheet 4 of 5 US 9,115,913 B1

FIG. 4

FIG. 5

Page 6

U.S. Patent Aug. 25,2015 Sheet 5 of 5 US 9,115,913 B1

FIG. 6

Page 7

US 9,115,913 Bl

1
FLUID HEATER

FIELD OF DISCLOSURE

This disclosure relates to heat transfer systems, and in
particular to devices for transferring heat to a fluid.

BACKGROUND

Many heat transfer systems use hot fluids as a heat transfer
medium. Such systems include a heat generator for generat-
ing heat, a heat transfer medium in thermal communication
with the energy source, and a pump to move the heated
medium to wherever the heat is needed. Because of its high
heat capacity and its abundance, a common heat transfer fluid
is water, both in its liquid and gas phase.

A variety of heat generators are in common use. For
instance, in nuclear power plants, nuclear fission provides
energy for heating water. There also exist solar water heaters
that use solar energy. However, most heat transfer sources
rely on an exothermal chemical reaction, and in particular, on
combustion of some fuel.

SUMMARY

In one aspect, the invention features an apparatus for heat-
ing fluid, the apparatus including a tank for holding fluid to be
heated, and a fuel wafer in fluid communication with the fluid,
the fuel wafer including a fuel mixture including reagents and
acatalyst, and a heat source, for example an electrical resistor,
in thermal communication with the fuel mixture and the cata-
lyst.

Among the embodiments are those in which the fuel mix-
ture includes lithium and lithium aluminum hydride, those in
which the catalyst includes a group 10 element, such as nickel
in powdered form, or in any combination thereof.

In other embodiments, the catalyst in powdered form, has
been treated to enhance its porosity. For example, the catalyst
can be nickel powder that has been treated to enhance poros-
ity thereof.

In those embodiments that include an electrical resistor, the
apparatus can also include an electrical energy source, suchas
a voltage source or current source in electrical communica-
tion with the resistor.

Among the other embodiments are those in which the fuel
wafer includes a multi-layer structure having a layer of the
fuel mixture in thermal communication with a layer contain-
ing the electrical resistor.

In yet other embodiments, the fuel wafer includes a central

heating insert and a pair of fuel inserts disposed on either side

of the heating insert.

A variety of tanks can be used. For example, in some
embodiments, the tank includes a recess for receiving the fuel
wafer therein. Among these are embodiments in which the
tank further includes a door for sealing the recess. In yet other
embodiments the tank includes a radiation shield.

Also included among the embodiments are those that fur-
ther include a controller in communication with the voltage
source. Among these are controllers that are configured to
cause vary the voltage in response to temperature of the fluid
to be heated.

In another aspect, the invention features an apparatus for
heating a fluid, the apparatus including means for containing
the fluid, and means for holding a fuel mixture containing a
catalyst and a reagent, and means for initiating a reaction
sequence mediated by the catalyst to cause an exothermic
reaction.

S

w

4

2

Another aspect of the invention is a composition of matter
for generating heat, the composition including a mixture of
porosity-enhanced nickel powder, lithium powder, and
lithium aluminum powder, and a heat source in thermal com-
munication with the mixture for initiating a nickel catalyzed
exothermic reaction.

Another aspect of the invention is a method of heating a
fluid, the method including placing a mixture of nickel pow-
der, lithium powder, and lithium aluminum hydride in ther-
mal communication with the fluid; and heating the mixture,
thereby initiating an exothermic reaction in the mixture.

These and other features of the invention will be apparent
from the following detailed description and the accompany-
ing figures, in which:

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a heat transfer system having a heat source;

FIG. 2 is a cut-away view of the heat source in FIG. 1;

FIG. 3 is a cross-section of the wafer for use in the heat
source of FIG. 2;

FIG. 4 shows an exemplary resistor in the central layer of
the wafer shown in FIG. 3.

FIG. 5 shows the heat source of FIG. 1 operating with a
conventional furnace.

FIG. 6 shows plural heat sources like that in FIG. 2 con-
nected in series.

FIG. 7 shows plural heat sources like that in FIG. 2 con-
nected in parallel.

DETAILED DESCRIPTION

Referring to FIG. 1, a heat transfer system 10 includes a
pipe 12 for transporting a heated fluid in a closed loop
between a heat source 14 anda thermal load 16. In most cases,
for example where there is hydraulic resistance to be over-
come, a pump 18 propels the heated fluid. However, in some
cases, such as where the heated fluid is steam, the fluid’s own
pressure is sufficient to propel the fiuid. A typical thermal load
16 includes radiators such as those commonly used for heat-
ing interior spaces.

As shown in FIG. 2, the heat source 14 is a tank 20 having,
a lead composite shield, an inlet 22 and an outlet 24, both of
which are connected to the pipe 12. The interior of the tank 20
contains fluid to be heated. In many cases, the fluid is water.
However, other fluids can be used. In addition, the fluid need
not be a liquid fluid but can also be a gas, such as air.

The tank 20 further includes a door 26 that leads to a
receptacle 28 protruding into the tank 20. Radiating fins 30
protrude from walls of the receptacle 28 into the tank 20. To
maximize heat transfer, the receptacle 28 and the fins 30 are
typically made of a material having high thermal conductiv-
ity, such as metal. A suitable metal is one not subject to
corrosion, such as stainless steel.

The receptacle 28 holds a multi-layer wafer 32 for gener-
ating heat. A voltage source 33 is connected to the wafer 32,
and a controller 35 for controlling the voltage source 33 in
response to temperature of fluid in the tank 12 as sensed by a
sensor 37.

As shown in FIG. 3, the multilayer fuel wafer 32 includes
a heating section 34 sandwiched between two fuel sections
36, 38. The heating section 34 features a central layer 40 made
ofan insulating material, such as mica, that supports a resistor
42. FIG. 4 shows an exemplary central layer 40 having holes
44 through which a resistive wire 42 has been wound. This
resistive wire 42 is connected to the voltage source 33. First
and second insulating layers 46, 48, such as mica layers,

Page 8

US 9,115,913 Bl

3

encase the central layer 40 to provide electrical insulation
from the adjacent fuel sections 36, 38.

Each fuel section 36, 38 features a pair of thermally con-
ductive layers 50, 52, such as steel layers. Sandwiched

between each pair of conductive layers 50, 52 isa fuel layer54 5

that contains a fuel mixture having nickel, lithium, and
lithium aluminum hydride LiAIH, (“LAH”), all in powdered
form. Preferably, the nickel has been treated to increase its
porosity, for example by heating the nickel powder to for
times and temperatures selected to superheat any water
present in micro-cavities that are inherently in each particle of
nickel powder. The resulting steam pressure causes explo-
sions that create larger cavities, as well as additional smaller
nickel particles.

The entire set of layers is welded together on all sides to
forma sealed unit. The size of the wafer 32 is not important to
its function. However, the wafer 32 is easier to handle if it is
on the order of 4 inch thick and 12 inches on each side. The
steel layers 50, 52 are typically 1 mm thick, and the mica
layers 40, 48, which are covered by a protective polymer
coating, are on the order of 0.1 mm thick. However, other
thicknesses can also be used.

In operation, a voltage is applied by the voltage source 33
to heat the resistor 42. Heat from the resistor 42 is then
transferred by conduction to the fuel layers 54, where it
initiates a sequence of reactions, the last of which is revers-
ible. These reactions, which are catalyzed by the presence of
the nickel powder, are:

3LIAIH,Li,AlHg#2Al43H,
2LiyAlHy+6LiH+2A143H

2LiH+2Al>2LiAl+H>

Once the reaction sequence is initiated, the voltage source
33 can be turned off, as the reaction sequence is self-sustain-
ing. However, the reaction rate may not be constant. Hence, it
may be desirable to turn on the voltage source 33 at certain
times to reinvigorate the reaction. To determine whether or
not the voltage source 33 should be turned on, the temperature
sensor 37 provides a signal to the controller 35, which then
determines whether or not to apply a voltage in response to
the temperature signal. It has been found that after the reac-
tion has generated approximately 6 kilowatt hours of energy,
it is desirable to apply approximately 1 kilowatt hour of
electrical energy to reinvigorate the reaction sequence.

Eventually, the efficiency of the wafer 32 will decrease to
the point where it is uneconomical to continually reinvigorate
the reaction sequence. At this point, the wafer 32 can simply
be replaced. Typically, the wafer 32 will sustain approxi-

mately 180 days of continuous operation before replacement °

becomes desirable.

The powder in the fuel mixture consists largely of spherical
particles having diameters in the nanometer to micrometer
range, for example between 1 nanometer and 100 microme-
ters. Variations in the ratio of reactants and catalyst tend to
govern reaction rate and are not critical. However, ithas been
found that a suitable mixture would includea starting mixture
of 50% nickel, 20% lithium, and 30% LAH. Within this
mixture, nickel acts as a catalyst for the reaction, and is not
itself a reagent. While nickel is particularly useful because of
its relative abundance, its function can also be carried out by
other elements in column 10 of the periodic table, such as
platinum or palladium.

FIGS. 5-7 show a variety of ways to connect the heat source
14 in FIG. 1.

S

8

w

8

&

4

In FIG. 5, the heat source 14 is placed downstream from a
conventional furnace 56. In this case, the controller 35 is
optionally connected to control the conventional furnace. As
aresult, the conventional furnace 56 will remain off unless the
output temperature of the heat source 14 falls below some
threshold, at which point the furnace 56 will start. In this
configuration, the conventional furnace 56 functions as a
back-up unit.

In FIG. 6, first and second heat sources 58, 60 like that
described in FIGS. 1-4 are connected in series. This configu-
ration provides a hotter output temperature than can be pro-
vided with only a single heat source 58 by itself. Additional
heat sources can be added in series to further increase the
temperature.

In FIG. 7, first and second heat sources 62, 64 like that
described in FIGS. 1-4 are connected in parallel. In this con-
figuration, the output volume can be made greater than what
could be provided by a single heat transfer unit by itself.
Additional heat transfer units can be added in parallel to
further increase volume.

Having described the invention, and a preferred embodi-
ment thereof, what I claim as new and secured by Letters
Patent is:

1. An apparatus for heating fluid, said apparatus compris-
inga tank, an electrical resistor, and a fuel wafer, wherein said
tank is configured for holding fluid to be heated, wherein said
fuel wafer is configured to be in thermal communication with
said fluid, wherein said fuel wafer includes a fuel mixture that
includes reagents and a catalyst, wherein said electrical resis-
tor is in thermal communication with said fuel mixture and
said catalyst, wherein said resistor is configured to be coupled
to a voltage source, wherein said apparatus further comprises
acontroller in communication with said voltage source, anda
temperature sensor, wherein said fuel mixture comprises
lithium, and lithium aluminum hydride, wherein said catalyst
comprises a group 10 element, wherein said controller is
configured to monitor a temperature from said temperature
sensor, and, based at least in part on said temperature, to
reinvigorate a reaction in said fuel mixture, wherein reinvigo-
rating said reaction comprises varying a voltage of said volt-
age source.

2. The apparatus of claim 1, wherein said catalyst com-
prises nickel powder.

3. The apparatus of claim 2, wherein said nickel powder has
been treated to enhance porosity thereof.

4. The apparatus of claim 1, wherein said fuel wafer com-
prises a multi-layer structure having a layer of said fuel mix-
ture in thermal communication with a layer containing said
electrical resistor.

5. The apparatus of claim 1, wherein said fuel wafer com-
prises a central heating insert and a pair of fuel inserts dis-
posed on either side of said heating insert.

6. The apparatus of claim 1, wherein said tank comprises a
recess for receiving said fuel wafer therein.

7. The apparatus of claim 6, wherein said tank further
comprises a door for sealing said recess.

8. The apparatus of claim 1, wherein said tank comprises a
radiation shield.

9. The apparatus of claim 1, wherein said reaction in said
fuel mixture is at least partially reversible.

10. The apparatus of claim 9, wherein said reaction com-
prises reacting lithium hydride with aluminum to yield hydro-
gen gas.