U.S. patent application number 12/504787 was filed with the patent office on 2010-01-14 for energy recuperation system.
Invention is credited to Stephane BILODEAU.
Application Number | 20100006255 12/504787 |
Document ID | / |
Family ID | 39635608 |
Filed Date | 2010-01-14 |
United States Patent
Application |
20100006255 |
Kind Code |
A1 |
BILODEAU; Stephane |
January 14, 2010 |
ENERGY RECUPERATION SYSTEM
Abstract
An energy recuperation system for storing energy in a process
for subsequent supply to an energy demand in the process comprises
a recuperation storage system having a phase-change storage
material. Recuperation circuitry between the energy
loss/availability, the energy demand of the process/processes and
the recuperation storage system to allow heat exchanges
therebetween. A controller obtains temperature data with respect to
the storage material, the energy loss/availability and/or the
recuperation circuitry so as to selectively actuate the
recuperation circuitry. An energy level calculator determines a
storage capacity in the recuperation storage system as a function
of temperature data of the storage material. An operation
identifier determines when to store energy in the recuperation
storage system and when to supply energy to the process as a
function of the storage capacity and of process data, whereby the
controller actuates the recuperation circuitry to store and supply
energy from/to the process.
Inventors: |
BILODEAU; Stephane;
(Sherbrooke, CA) |
Correspondence
Address: |
OGILVY RENAULT LLP
1, Place Ville Marie, SUITE 2500
MONTREAL
QC
H3B 1R1
CA
|
Family ID: |
39635608 |
Appl. No.: |
12/504787 |
Filed: |
July 17, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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PCT/CA08/00093 |
Jan 17, 2008 |
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12504787 |
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60885270 |
Jan 17, 2007 |
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Current U.S.
Class: |
165/10 |
Current CPC
Class: |
F28D 20/028 20130101;
Y02E 60/14 20130101; Y02E 60/145 20130101; C09K 5/063 20130101 |
Class at
Publication: |
165/10 |
International
Class: |
F28D 17/00 20060101
F28D017/00 |
Claims
1. An energy recuperation system for storing energy from an energy
loss/availability in a process/processes for subsequent supply to
an energy demand in the process/processes, comprising: a
recuperation storage system having a storage material being
selected so as to change phase during heat exchanges with the
process/processes; at least one recuperation circuit between the
energy loss/availability, the energy demand of the
process/processes and the recuperation storage system for heat
exchanges between (1) the energy loss/availability and the
recuperation storage system, and (2) the recuperation storage
system and the energy demand; a controller for obtaining
temperature data with respect to at least one of the storage
material, the energy loss/availability and the at least one
recuperation circuit so as to selectively actuate the recuperation
circuit; an energy level calculator for determining a storage
capacity in the recuperation storage system as a function of
temperature data of the storage material; and an operation
identifier for determining when to store energy in the recuperation
storage system and when to supply energy to the process/processes
as a function of the storage capacity and of process data; whereby
the controller actuates the at least one recuperation circuit to
store energy from the process/processes in the recuperation storage
system and to supply energy from the recuperation storage system to
the process/processes.
2. The energy recuperation system according to claim 1, wherein the
energy recuperation system is used between a heating demand and a
cooling demand of a process/processes, with the operation
identifier determining when to store in the recuperation storage
system cold energy from the heating demand and hot energy from the
cooling demand, and when to supply hot energy to the heating demand
and cold energy to the cooling demand of the process/processes as a
function of the storage capacity and of the process data, whereby
the controller actuates the at least one refrigeration circuit (1)
to store in the recuperation storage system cold energy recuperated
from the heating demand of the process/processes and to supply said
cold energy from the recuperation storage system to the cooling
demand of the process/processes, and (2) to store in the
recuperation storage system hot energy recuperated from the cooling
demand of the process/processes and to supply said hot energy from
the recuperation storage system to the heating demand of the
process/processes.
3. The energy recuperation system according to claim 1, wherein the
energy loss/availability is a cold energy loss.
4. The energy recuperation system according to claim 1, comprising
two of said recuperation circuit, with one said recuperation
circuit being provided between the energy loss/availability and the
recuperation storage system for heat exchanges therebetween, and
the other one of said recuperation circuit being provided between
the recuperation storage system and the energy demand.
5. The energy recuperation system according to claim 1, wherein the
operation identifier is connected to a process controller
controlling the process/processes, so as to obtain said process
data from the process controller.
6. The energy recuperation system according to claim 2, wherein the
recuperation storage system has two separated storage materials,
with a first one of the storage materials provided to store cold
energy from the heating demand to then supply the cold energy to
the cooling demand, and with a second one of the storage materials
provided to store hot energy from the cooling demand to then supply
the hot energy to the heating demand.
7. The energy recuperation system according to claim 6, wherein the
two separated storage materials are different storage
materials.
8. The energy recuperation system according to claim 1, wherein the
energy loss/availability is cold energy available from any one of a
cooling tower, dry cooler and heat rejection apparatus, with the at
least one recuperation circuit being connected between the cooling
tower and the recuperation storage system for heat exchanges
between the cooling tower and the recuperation storage system, to
store cold energy in the recuperation storage system.
9. The energy recuperation system according to claim 8, further
comprising a heat transfer apparatus and a cold transfer circuit,
with the at least one recuperation circuit being provided between
the energy availability and the heat transfer apparatus, and the
cold transfer circuit being provided between the heat transfer
apparatus and the recuperation storage system.
10. The energy recuperation system according to claim 9, wherein
the heat transfer apparatus is any one of a heat exchanger, a
chiller and a heat pump.
11. The energy recuperation system according to claim 1, further
comprising a heat transfer apparatus provided between the energy
availability and the recuperation storage system.
12. The energy recuperation system according to claim 11, wherein
the heat transfer apparatus is any one of a heat pump, a chiller, a
heat pipe and a heat exchanger.
13. The energy recuperation system according to claim 1, further
comprising a heat recovery unit in heat exchange relation with the
at least one recuperation circuit and with an alternative energy
source, to store energy in the recuperation storage system from the
alternative energy source.
14. The energy recuperation system according to claim 1, wherein
the storage material is a compound comprising at least one of
alkanes, N-paraffin hydrocarbon chain, glycerin, water, tridecane,
tetradecanes, pentadecane, hexadecane, heptadecane, hydrocarbon
wax, glycerol, 1,2,3-Propanetriol, glyceritol, glycerol, estol,
1,2,3-trihydroxypropane, glycyl alcohol, triglycerides, fatty
acids, esthers, iso-propyl palmitate, silicone gel, salt
hydrates.
15. A method for recuperating energy comprising: identifying energy
loss/availability from an energy source; storing energy from the
energy loss/availability by heat exchange between the energy
loss/availability and a storage material such that the storage
material changes phase through the heat exchange; identifying an
energy demand in a process; and supplying energy to the energy
demand by heat exchange between the storage material and the energy
demand.
16. The method according to claim 15, wherein identifying the
energy loss/availability comprises identifying the energy
loss/availability from a heating demand of a first process, and
identifying the energy demand comprises identifying a cooling
demand in the first process or in a second process, whereby storing
energy comprises subsequently storing cold and hot energy in the
storage material.
17. The method according to claim 16, wherein storing energy
comprises storing cold energy from the heating demand in a first
one of the storage material, and storing hot energy from the
cooling demand in a second one of the storage material such that
the storage materials respectively change phase through the heat
exchanges.
18. The method according to claim 16, further comprising
identifying energy loss/availability from an alternative energy
source, and storing energy from the energy loss/availability by
heat exchange between the alternative energy source and a storage
material such that the storage material changes phase through the
heat exchange.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present patent application is a continuation of
International Patent Application No. PCT/CA2008/000093, filed on
Jan. 17, 2008, and claims priority on U.S. Provisional Patent
Application No. 60/885,270, filed on Jan. 17, 2007.
FIELD OF THE APPLICATION
[0002] The present application relates to energy management and,
more particularly, to an energy recuperation storage system used in
conjunction with a building or an industrial process or processes
to recuperate energy.
BACKGROUND OF THE ART
[0003] The ever-increasing costs of energy are associated with
numerous factors: increasing energy demand for full capacity
supply, diminishing stocks of fossil fuel, volatility of the supply
capacity in view of political, geographical and meteorological
factors. Therefore, energy management has rapidly evolved to
minimize the impact of high energy costs, and cost variations.
[0004] In a plurality of industrial processes, a product being
produced may require to be heated and then cooled. As an example,
in the food industry, some products are cooked by being exposed to
heat, and are then cooled prior to being packed. In another
instance, in the cosmetics industry, products such as creams,
shampoos, must be heated and cooled as part of their production
process.
[0005] In these instances, the energy required to heat the product
is often lost when the product is cooled. Accordingly, such energy
consumption is inefficient, and has a direct effect on the cost of
producing the product. Moreover, such non-optimized energy
consumption could potentially prove harmful for the environment in
the long run.
SUMMARY OF THE APPLICATION
[0006] It is therefore an aim of the present application to provide
an energy accumulator system that addresses the issues associated
with the prior art.
[0007] Therefore, in accordance with a first embodiment of the
present application, there is provided an energy recuperation
system for storing energy from an energy loss/availability in a
process/processes for subsequent supply to an energy demand in the
process/processes, comprising: a recuperation storage system having
a storage material being selected so as to change phase during heat
exchanges with the process/processes; at least one recuperation
circuit between the energy loss/availability, the energy demand of
the process/processes and the recuperation storage system for heat
exchanges between (1) the energy loss/availability and the
recuperation storage system, and (2) the recuperation storage
system and the energy demand; a controller for obtaining
temperature data with respect to at least one of the storage
material, the energy loss/availability and the at least one
recuperation circuit so as to selectively actuate the recuperation
circuit; an energy level calculator for determining a storage
capacity in the recuperation storage system as a function of
temperature data of the storage material; and an operation
identifier for determining when to store energy in the recuperation
storage system and when to supply energy to the process/processes
as a function of the storage capacity and of process data; whereby
the controller actuates the at least one recuperation circuit to
store energy from the process/processes in the recuperation storage
system and to supply energy from the recuperation storage system to
the process/processes.
[0008] In accordance with the first embodiment, the energy
recuperation system is used between a heating demand and a cooling
demand of a process/processes, with the operation identifier
determining when to store in the recuperation storage system cold
energy from the heating demand and hot energy from the cooling
demand, and when to supply hot energy to the heating demand and
cold energy to the cooling demand of the process/processes as a
function of the storage capacity and of the process data, whereby
the controller actuates the at least one refrigeration circuit (1)
to store in the recuperation storage system cold energy recuperated
from the heating demand of the process/processes and to supply said
cold energy from the recuperation storage system to the cooling
demand of the process/processes, and (2) to store in the
recuperation storage system hot energy recuperated from the cooling
demand of the process/processes and to supply said hot energy from
the recuperation storage system to the heating demand of the
process/processes.
[0009] Still in accordance with the first embodiment, the energy
loss/availability is a cold energy loss.
[0010] Still in accordance with the first embodiment, the energy
recuperation system comprises two of said recuperation circuit,
with one said recuperation circuit being provided between the
energy loss/availability and the recuperation storage system for
heat exchanges therebetween, and the other one of said recuperation
circuit being provided between the recuperation storage system and
the energy demand.
[0011] Still in accordance with the first embodiment, the operation
identifier is connected to a process controller controlling the
process/processes, so as to obtain said process data from the
process controller.
[0012] Still in accordance with the first embodiment, the
recuperation storage system has two separated storage materials,
with a first one of the storage materials provided to store cold
energy from the heating demand to then supply the cold energy to
the cooling demand, and with a second one of the storage materials
provided to store hot energy from the cooling demand to then supply
the hot energy to the heating demand.
[0013] Still in accordance with the first embodiment, the two
separated storage materials are different storage materials.
[0014] Still in accordance with the first embodiment, the energy
loss/availability is cold energy available from any one of a
cooling tower, dry cooler and heat rejection apparatus, with the at
least one recuperation circuit being connected between the cooling
tower and the recuperation storage system for heat exchanges
between the cooling tower and the recuperation storage system, to
store cold energy in the recuperation storage system.
[0015] Still in accordance with the first embodiment, the energy
recuperation system comprises a heat transfer apparatus and a cold
transfer circuit, with the at least one recuperation circuit being
provided between the energy availability and the heat transfer
apparatus, and the cold transfer circuit being provided between the
heat transfer apparatus and the recuperation storage system.
[0016] Still in accordance with the first embodiment, the heat
transfer apparatus is any one of a heat exchanger, a chiller and a
heat pump.
[0017] Still in accordance with the first embodiment, the energy
recuperation system comprises a heat transfer apparatus provided
between the energy availability and the recuperation storage
system.
[0018] Still in accordance with the first embodiment, the heat
transfer apparatus is any one of a heat pump, a chiller, a heat
pipe and a heat exchanger.
[0019] Still in accordance with the first embodiment, the energy
recuperation system comprises a heat recovery unit in heat exchange
relation with the at least one recuperation circuit and with an
alternative energy source, to store energy in the recuperation
storage system from the alternative energy source.
[0020] Still in accordance with the first embodiment, the storage
material is a compound comprising at least one of alkanes,
N-paraffin hydrocarbon chain, glycerin, water, tridecane,
tetradecanes, pentadecane, hexadecane, heptadecane, hydrocarbon
wax, glycerol, 1,2,3-Propanetriol, glyceritol, glycerol, estol,
1,2,3-trihydroxypropane, glycyl alcohol, triglycerides, fatty
acids, esthers, iso-propyl palmitate, silicone gel, salt
hydrates.
[0021] In accordance with a second embodiment of the present
application, there is provided a method for recuperating energy
comprising: identifying energy loss/availability from an energy
source; storing energy from the energy loss/availability by heat
exchange between the energy loss/availability and a storage
material such that the storage material changes phase through the
heat exchange; identifying an energy demand in a process; and
supplying energy to the energy demand by heat exchange between the
storage material and the energy demand.
[0022] In accordance with the second embodiment, identifying the
energy loss/availability comprises identifying the energy
loss/availability from a heating demand of a first process, and
identifying the energy demand comprises identifying a cooling
demand in the first process or in a second process, whereby storing
energy comprises subsequently storing cold and hot energy in the
storage material.
[0023] Still in accordance with the second embodiment, the method
comprises storing cold energy from the heating demand in a first
one of the storage material, and storing hot energy from the
cooling demand in a second one of the storage material such that
the storage materials respectively change phase through the heat
exchanges.
[0024] Still in accordance with the second embodiment, the method
comprises identifying energy loss/availability from an alternative
energy source, and storing energy from the energy loss/availability
by heat exchange between the alternative energy source and a
storage material such that the storage material changes phase
through the heat exchange.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a block diagram illustrating an energy
recuperation system for batch recuperation in accordance with an
embodiment of the present application;
[0026] FIG. 2 is a block diagram illustrating an energy
recuperation system for continuous recuperation in accordance with
an embodiment of the present application;
[0027] FIG. 3 is a block diagram illustrating the energy
recuperation system of FIG. 1, as used with cold energy
availability external to a process; and
[0028] FIG. 4 is a block diagram illustrating the energy
recuperation system of FIG. 1, with additional heat transfer
apparatus and heat recovery unit.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] Referring now to the drawings and more particularly to FIG.
1, an energy recuperation system is generally shown at 10, and will
hereinafter be referred to as the ERS 10. In a first embodiment,
the ERS 10 is used in conjunction with a process having a cooling
demand/heat availability A and a heating demand/cool availability
B.
[0030] The cooling demand/heat availability A (hereinafter cooling
demand A) is a part of the process in which the product must be
cooled or, in the alternative, in which heat may be/must be
absorbed.
[0031] The heating demand/cool availability B (hereinafter heating
demand B) is a part of the process in which the product must be
heated or, in the alternative, in which heat can be released.
[0032] The ERS 10 has a recuperation storage system 11, a
controller system 12, a heat recuperation circuit 13, and a cold
recuperation circuit 14. In the embodiment of FIG. 1, the
recuperation storage system 11 is a reservoir having a storage
material. The storage material is chosen as a function of the
cooling demand A and of the heating demand B, so as to change
phases (e.g., solid/liquid, or liquid/vapor) in the process of
recuperating energy.
[0033] The storage material is chosen so as to change phase (e.g.,
solid to liquid, liquid to gas or vice-versa) under generally
atmospheric pressure within the recuperation storage system 11,
following a heat-exchange sequence with a thermo-fluid that is part
of the heat recuperation circuit 13 and/or cold recuperation
circuit 14. It is preferred that the storage material undergo a
phase change (e.g., liquid-solid and vice versa) as a function of
the temperature variation required for the first refrigerant, so as
to maximize the heat-retaining capacity of the energy recuperation
by using the latent heat capacity of the recuperation
refrigerant.
[0034] The storage material is a compound of different materials
which may include alkanes, N-paraffin hydrocarbon chain, glycerin,
water, tridecane, tetradecanes, pentadecane, hexadecane,
heptadecane, hydrocarbon wax, glycerol, 1,2,3-Propanetriol,
glyceritol, glycerol, estol, 1,2,3-trihydroxypropane, glycyl
alcohol, triglycerides, fatty acids, esthers, iso-propyl palmitate,
silicone gel, salt hydrates, appropriately chosen as a function of
the cooling demand A and the heating demand B.
[0035] The recuperation storage system 11 communicates with the
cooling demand A by way of the heat recuperation circuit 13 to
absorb heat, and with the heating demand B by way of the cold
recuperation circuit 14, to supply heat as a function of the
demand.
[0036] In an embodiment, the heat and the cold recuperation
circuits 13 and 14 are connected to a regeneration system which is
used to charge the storage material at very low energy cost or with
rejected energy, such as a dry cooler system with fans in heat
exchange with the outside air (Direct free cooling module), the
heat rejection of cooling tower of chilled water system or an
economizer integrated to a chimney or on the exhaust air of a
specific process. Examples are provided hereinafter.
[0037] The heat recuperation circuit 13 and the cold recuperation
circuit 14 typically are piping circuits extending between
respective parts of the process and the recuperation storage system
11. Both circuits 13 and 14 are in a heat-exchange relation with
the process and with the energy accumulator 11, but preferably not
in fluid communication therewith. To be in heat-exchange relation,
the circuits 13 and 14 are provided with heat exchangers, which are
chosen as a function of the process and/or recuperation
refrigerant.
[0038] Thermo-fluids circulate in the circuits 13 and 14, such as
water, ethylene-glycol, propylene glycol, thermal oil, etc. Pumps
or similar conveying means (compressed air network, etc.) are
provided to induce the circulation of the thermo-fluids in the
circuits 13 and 14. It is contemplated to have the circuits 13 and
14 in fluid communication with one another in a global circuit with
suitable valves and controls. Similarly, the circuits 13 and 14 may
be a same single circuit if a single part of the process needs
cooling and heating (e.g., a tank in which the product is heated
and then cooled).
[0039] The ERS 10 has a controller system 12. The controller system
12 is a computer having a processor. The controller system 12 is
connected to the cooling demand A, to the heating demand B, and to
the recuperation storage system 11, so as to obtain various
information that will be used in operating the heat recuperation
circuit 13 and the cold recuperation circuit 14 to recuperate
energy.
[0040] Referring to FIG. 1, the controller system 12 has a
controller 20. The controller 20 is connected to the recuperation
storage system 11, so as to obtain temperature data, or like
parameters, associated with the storage medium.
[0041] The controller 20 is also connected to the cooling demand A
and to the heating demand B of the process, for instance by way of
various sensors (e.g., pressure sensors, temperature sensors [dry
bulb and wet bulb temperatures] and probes, and the like), so as to
obtain information pertaining to the energy demand. More
specifically, the process is often precisely controlled to ensure,
for instance, that the product is produced according to given
standards. Accordingly, the process is typically equipped with
sensors and the like obtaining accurate parameter data (e.g.,
temperatures, pressures, etc.). It is therefore contemplated to
connect the sensors of the process to the controller 20 such that
the controller 20 obtains the parameter data illustrating the
cooling demand A and the heating demand B.
[0042] The controller 20 is connected to the various powered
devices (e.g., pumps, solenoids valves, etc.) of the heat
recuperation circuit 13 and of the cold recuperation circuit 14,
which induce the flow of thermo-fluid between the demands A and B
and the recuperation storage system 11. The controller 20 therefore
commands actuation of the circuits 13 and 14, as a function of the
decisions taken by the controller system 12, to recuperate and
store energy in the recuperation storage system 11.
[0043] An energy level calculator 21 is associated with the
controller 20. The energy level calculator 21 receives the
temperature data pertaining to the cooling demand A and to the
heating demand B of the process, and to the storage medium in the
recuperation storage system 11. With the temperature data, the
energy level calculator 21 calculates the real-time storage
capacity in the recuperation storage system 11.
[0044] The storage capacity value is the amount of additional
energy that can be stored in the recuperation storage system 11,
under a desired condition of the storage material. Considering that
the storage material is preferably to change phase when
accumulating heat, the storage capacity value may be a calculation
of the proportion of storage material that has yet to change phase
(i.e., the capacity to store latent heat).
[0045] An operation identifier 22 is associated with the controller
20. The operation identifier 22 receives the storage capacity value
of the recuperation storage system 11 from the controller 20, as
calculated by the energy level calculator 21. Other information
that is provided to the operation identifier is the temperature
data of the recuperation storage system 11, and the heat demand
value.
[0046] The operation identifier 22 will therefore determine if and
when one of heat recuperation circuit 13 and the cold recuperation
circuit 14 is to be actuated to store energy in the recuperation
storage system 11, in order to optimize energy consumption in view
of the demands/requirements of the process.
[0047] Alternatively, a process controller C is provided to control
the operation of the process. More specifically, a process is a
sequence of steps that are often automated, whereby a process
controller C typically controls the process, for instance by
actuating the powered devices, by measuring the parameters
associated with the process, etc.
[0048] It is therefore considered to connect the process controller
C to the operation identifier 22, such that the process controller
C may indicate, in the form of process info, that a given step of
the process has been reached and that there is a cooling
demand/availability A or a heating demand/availability B at this
step of the process.
[0049] With or without this additional process information, the
operation identifier 22 determines whether and when to send
actuation commands to the controller 20 such that either the heat
recuperation circuit 13 or the cold recuperation circuit 14 is
actuated to initiate energy recuperation.
[0050] Moreover, a database 23 is provided to store process data.
Such information may be considered by the operation identifier 22
to determine from the process parameters (e.g., temperature,
pressure) when to initiate recuperation of energy through actuation
commands. The process data stored in the database 23 may be
updated.
First Example of Operation
[0051] The operation identifier 22 determines that, as a function
of the storage capacity of the recuperation storage system 11 and
of an indication from the process controller C that the process has
a cooling demand A, the ERS 10 is capable of absorbing energy.
Actuation commands are sent to the controller 20 by the operation
identifier 22, such that the thermo-fluid is circulated between the
recuperation storage system 11 and the cooling demand A. Heat is
absorbed by the thermo-fluid and then released to the refrigerant
in the recuperation storage system 11.
[0052] Throughout this heat exchange, the energy level calculator
21 calculates the storage capacity of the recuperation storage,
which information is updated with the operation identifier 22. Upon
receiving process information from the process controller C
indicating that the step requiring the cooling demand A is
finished, or determining from the storage capacity that the heat
exchange must end, the operation identifier 22 commands the
controller 20 to stop the actuation of the heat recuperation
circuit 13.
[0053] The operation identifier 22 will subsequently determine how
the energy stored in the recuperation storage system 11 can be
used. For instance, if the energy level in the storage system 11 is
high, the operation identifier 22 may wait for a demand indication
of the process controller C to have the cold recuperation circuit
14 actuated to meet the heating demand B.
[0054] Therefore, the use of ERS 10 allows energy to be stored for
later use. The demands A and B do not have to be synchronized for
the heat exchange to occur, as the storage removes the factor of
time from the heat exchange.
Second Example of Operation
[0055] In a second example, the cooling demand/heat availability A
is a chimney releasing the by-products of combustion to the
atmosphere. Accordingly, when combustion occurs, the by-products
are a continuous source of heat that would otherwise be lost.
[0056] Therefore, the operation identifier 22, receiving
information from the energy level calculator 21 as well as
temperature data from the chimney or indications from the process
controller C, commands actuation of the heat recuperation circuit
13 to store energy in the recuperation storage system 11.
[0057] Upon restoring the energy level in the storage system 11,
the ERS 10 is in standby until there is a heating demand B. At this
point, the operation identifier 22 commands actuation of the cold
recuperation circuit 14 to provide heat to the heating demand B of
the process, until the end of the demand B or depletion of the
stored energy in the recuperation storage system 11.
Third Example of Operation
[0058] In a third example, referring to FIG. 3, the cooling
availability B is the outside air. Accordingly, when proper
conditions apply (appropriate wet bulb temperature and/or dry bulb
temperature), the cold recuperation circuit 14 benefits from a
continuous source of quasi-free cold or mild temperature heat to be
stored and that would otherwise be unusable. The cold recuperation
circuit 14 is connected to a cooling tower, a dry cooler, a heat
rejection apparatus or the like, all of which are the cold
availability B.
[0059] Therefore, the operation identifier 22, receiving
information from the energy level calculator 21 as well as
temperature data from the outside conditions sensors or indications
from the process controller C, commands actuation of the cold
recuperation circuit 14 to store energy in the recuperation storage
system 11.
[0060] Referring to FIG. 3, it is contemplated to additionally
provide a heat transfer apparatus 30 and a cold transfer circuit 31
between the cold recuperation circuit 14 and the recuperation
storage system 11. This heat transfer apparatus is used to separate
the two cold circuits (14 and 31) in order to allow the cold
transfer circuit to distribute energy to a sensible cooling process
which cannot be mixed with the cold recuperation circuit fluid (for
separate temperature control, for contamination risks reduction or
for other physical reasons). This isolation pattern allows for a
larger range of applications and energy consumption reductions with
the recuperation from external cool availability. The heat transfer
apparatus 30 is for example a heat exchanger, a chiller, or a heat
pump.
[0061] Upon restoring the energy level in the storage system 11,
the ERS 10 is in standby until there is a cooling demand B. At this
point, the operation identifier 22 commands actuation of the cold
recuperation circuit 14 to provide cold to the cooling demand B of
the process, until the end of the demand B or depletion of the
stored energy in the recuperation storage system 11.
Fourth Example of Operation
[0062] In a fourth example, referring to FIG. 4, a heat pump or
heat transfer apparatus 40 is provided between the heating
availability A and the heat recuperation circuit 13. The heat
transfer apparatus 40 is for instance a chiller (notably the heat
rejection/condenser side), a heat pipe or a heat exchanger, and is
provided to increase the coefficient of performance of the heat
recuperating loop between the heat availability A and the
recuperation storage system 11. Using a supplementary heat pump or
heat transfer apparatus 40 to provide the temperature differential,
generated by the heat availability, through the heat recuperation
circuit 13 to the recuperation system allows for an increase in the
energy quality supplied (e.g. higher temperature or enthalpy
content in the heat recuperation circuit 13) while reducing the
entropy generation and then improving significantly the energy
efficiency of the combined process.
[0063] Therefore, the operation identifier 22, receiving
information from the energy level calculator 21 as well as
temperature data from the heat availability A or indications from
the process controller C, commands actuation of the heat
recuperation circuit 13 to store energy in the recuperation storage
system 11.
[0064] Still referring to FIG. 4, it is contemplated to
additionally provide a heat recovery unit 41 in heat exchange
relation with the recuperation storage system 11. The heat recovery
unit 41 may be connected to either one of the recuperation circuits
13 or 14 (although connected to the circuit 14 in FIG. 3), and is
typically used in case where cold or hot energy is periodically
available (e.g., free cooling in Winter conditions). Accordingly,
the heat recovery unit 41 represents another option to recuperate
energy.
Alternative Embodiment
[0065] Referring to FIG. 2, in accordance with another embodiment,
the recuperation storage system 11 of the ERS 10 is divided into a
first recuperation storage 11A and a second recuperation storage
11B.
[0066] Accordingly, two opposite heat-exchange sequences can be
performed simultaneously. For instance, in a first sequence of heat
exchange, the heat recuperation circuit 13 circulates its
thermo-fluid between the first recuperation storage 11A and the
cooling demand/heat availability A, so as to absorb heat from the
cooing demand A. Simultaneously, the cold recuperation circuit 14
circulates its thermo-fluid between the second recuperation storage
11B and the heating demand/cool availability B, so as to absorb
heat from the heating demand B.
[0067] Once suitable energy levels are reached in storage 11A and
storage 11B, the sequence is reversed, in that the first
recuperation storage 11A supplies heat to the heating demand B,
whereas the second recuperation storage 11B absorbs heat from the
cooling demand A. These sequences of heat exchange are controlled
by the controller system 12 in the manner described above.
* * * * *