U.S. patent application number 11/815488 was filed with the patent office on 2008-06-05 for heat storage device with heat-radiative coating.
Invention is credited to Huimin Zhou.
Application Number | 20080128121 11/815488 |
Document ID | / |
Family ID | 35349426 |
Filed Date | 2008-06-05 |
United States Patent
Application |
20080128121 |
Kind Code |
A1 |
Zhou; Huimin |
June 5, 2008 |
Heat Storage Device with Heat-Radiative Coating
Abstract
Taught herein is a heat retainer for a heat exchanger the
retainer having a coating layer. At least one surface of the heat
retainer is coated with a highly-radiative material forming a
coating layer whose emissivity is greater than that of a substrate
material of which the core of the heat retainer is made. The heat
retainer is in the shape of a honeycomb, a fin, a ball, an ellipse
or a plate, and one or a plurality of inner holes are disposed
therein. The substrate of which the heat retainer is made is a
refractory material, a ceramic material or a steel material. The
heat retainer has comparatively good heat absorption and emission
performance; heat storage capacity is increased, diathermancy is
improved, and energy is saved.
Inventors: |
Zhou; Huimin; (Jinan,
CN) |
Correspondence
Address: |
MATTHIAS SCHOLL
14781 MEMORIAL DRIVE, SUITE 1319
HOUSTON
TX
77079
US
|
Family ID: |
35349426 |
Appl. No.: |
11/815488 |
Filed: |
November 15, 2005 |
PCT Filed: |
November 15, 2005 |
PCT NO: |
PCT/CN05/02010 |
371 Date: |
August 3, 2007 |
Current U.S.
Class: |
165/133 |
Current CPC
Class: |
F28D 20/0056 20130101;
F28D 17/02 20130101; Y02E 60/142 20130101; F28F 13/18 20130101;
F28F 2245/06 20130101; Y02E 60/14 20130101; F27D 1/042
20130101 |
Class at
Publication: |
165/133 |
International
Class: |
F28F 13/18 20060101
F28F013/18 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 17, 2005 |
CN |
200510043838.X |
Claims
1. A heat retainer for a heat exchanger the heat retainer having a
coating layer, wherein at least one surface of said heat retainer
is coated with a highly-radiative material forming said coating
layer.
2. The heat retainer of claim 1, wherein a thickness of said
coating layer is 0.02-3 mm.
3. The heat retainer of claim 1, wherein an emissivity of said
highly-radiative material is greater than that of a substrate
material of which the heat retainer is made.
4. The heat retainer of claim 1, wherein the heat retainer is in
the shape of a honeycomb, a fin, a ball, an ellipse or a plate.
5. The heat retainer of claim 1, comprising one or a plurality of
inner holes disposed within said heat retainer.
6. The heat retainer of claim 5, wherein the inner hole may be
circular, square, rectangular, rhombic, hexagonal or polygonal.
7. The heat retainer of claim 1, wherein a cross section of the
heat retainer is circular, square, rectangular, rhombic, hexagonal
or polygonal.
8. The heat retainer of claim 1, prepared by coating surfaces of
the substrate of the heat retainer with a pre-treating liquid and
then paste-coating, spray-coating or dip-coated with the
highly-radiative material to form a coating layer, wherein the
pre-treating liquid is an aqueous solution of the polyamine curing
agent PA80 or an alkali metal silicate.
9. The heat retainer of claim 1, wherein the substrate of the heat
retainer is made of a refractory material, a ceramic material, an
iron and a steel material.
Description
FIELD OF THE INVENTION
[0001] The invention relates to a heat exchanger and more
particularly to a heat exchanger with a highly-radiative coating
layer facilitating heat exchange.
DESCRIPTION OF THE RELATED ART
[0002] In industrial fields such as metallurgy, machinery and farm
product processing, heat exchangers are commonly-used. The main
function of a heat exchanger is to transfer heat to air or gas. One
type of heat exchangers uses coal, gas, oil or electricity as a
direct heat source. Another type of heat exchangers employs
secondary sources of heat. A heat source firstly transfers energy
to a heat retainer of the heat exchanger, and then air or gas that
needs to be heated is passed over it. During heat exchange between
the heat retainer and air or gas, heat is removed from the heat
retainer, and air or gas is heated. Generally, the heat retainer is
made of a refractory material, a ceramic material, an iron or a
steel material.
[0003] Heat absorption and emission capability of heat retainers is
an important factor for the heat exchange performance of a heat
exchanger, and is directly associated with power savings. To
improve the heat exchange efficiency of a heat exchanger, a
plurality of patents, such as CN2462326Y and CN2313197Y, provide
structural improvements. However, a heat exchanger employing a
coating layer made of highly radiative material has not heretofore
been proposed to improve the heat storage capability of the heat
retainer and, in turn, to improve the efficiency of the heat
exchanger.
SUMMARY OF THE INVENTION
[0004] To overcome the deficiencies of prior art, it is one
objective of the invention to provide a highly-efficient and
energy-saving heat retainer with a coating layer for facilitating
heat exchange.
[0005] The invention provides a heat retainer with a coating layer
for facilitating heat exchange, wherein at least one surface of the
heat retainer is coated with a coating layer made of a
highly-radiative material.
[0006] The thickness of the highly-radiative material coating layer
is 0.02-3 mm.
[0007] The emissivity of the highly-radiative material is greater
than that of the substrate material of which the core of the heat
retainer is made.
[0008] Advantageously, the highly-radiative material is a material
having an absorption rate and an emission rate higher than those of
the substrate material of which the core of the heat retainer is
made.
[0009] The heat retainer takes the shape of a honeycomb, a fin, a
ball, an ellipse or a plate.
[0010] One or a plurality of inner holes is disposed within the
heat retainer. The inner hole is circular, square, rectangular,
rhombic, hexagonal or polygonal. The substrate of the heat retainer
is made of a refractory material, a ceramic material, an iron or a
steel material.
[0011] A cross section of the heat retainer is circular, square,
rectangular, rhombic, hexagonal or polygonal.
[0012] The highly-radiative material is any suitable
highly-radiative far-infrared material suitable for a heat retainer
made of a refractory material, a ceramic material or a steel
material.
[0013] The coating layer made of highly-radiative material is
implemented by way of paste-coating, spray-coating or dip-coating,
and the heat retainer having the coating layer is used directly
after coating, or is used after high temperature curing.
[0014] Surfaces of the substrate of the heat retainer are
pre-treated with a pre-treating liquid prior to being paste-coated,
spray-coated or dip-coated with the highly-radiative material, so
as to further improve adhesion between the highly-radiative
material and the substrate.
[0015] The pre-treating liquid is an aqueous solution containing
polyamine curing agent PA80 (PA80 adhesive) or an alkali metal
silicate.
[0016] Solid components in the highly-radiative material are
hyperfinely processed, so as to enable the particle size to be
20-900 nm, and to improve adhesion between the highly-radiative
material and the substrate.
[0017] Surfaces of the heat retainer for the heat exchanger of the
invention are coated with a coating layer of highly-radiative
material whose emissivity is greater than that of the substrate
material of which the core of the heat retainer is made; the heat
absorption and emission capability of the heat exchanger is
increased, which improves heat absorption and emission of the heat
retainer, and increases the heat storage capacity.
[0018] Meanwhile, increasing the heat exchange efficiency of the
heat exchanger also saves energy. Particularly, when a checker
brick of a hot blast stove of a blast furnace is coated with the
highly radiative material, temperature inside the hot blast stove
is uniformly distributed, and the heat storage capacity is notably
increased. This raises the temperature of the circulating air,
shortens the startup period, and reduces the gas amount and air
flow. Reduction of the gas amount and the air flow further saves
energy, lowers the requirement of a wind turbine, and reduces the
overall cost of devices. The coating layer of the heat retainer
also operates to protect the substrate of which the core of the
heat retainer is made. When the surfaces of the heat retainer of a
steel-rolling regenerative furnace are coated with the
highly-radiative material, temperature inside the heat retainer
increases significantly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a diagram illustrating a honeycomb-shaped heat
retainer with a coating layer for a heat exchanger according to one
embodiment of the invention;
[0020] FIG. 2 is a diagram illustrating a honeycomb-shaped heat
retainer with a coating layer for a heat exchanger according to
another embodiment of the invention;
[0021] FIG. 3 is a diagram illustrating a fin-shaped heat retainer
with a coating layer for a heat exchanger according to another
embodiment of the invention;
[0022] FIG. 4 is a partial cross-sectional view illustrating a
plate-shaped heat retainer with a coating layer for a heat
exchanger according to yet another embodiment of the invention;
[0023] FIG. 5 is a partial cross-sectional view illustrating a
ball-shaped heat retainer with a coating layer for a heat exchanger
according to yet another embodiment of the invention;
[0024] FIG. 6 is a diagram illustrating an elliptical heat retainer
with a coating layer for a heat exchanger according to yet another
embodiment of the invention; and
[0025] FIG. 7 is a partial cross-sectional view illustrating a
non-metal heat retainer with a coating layer for a heat exchanger
according to yet another embodiment of the invention.
[0026] In the drawings: 1-circular inner hole; 2-highly-radiative
material coating layer; 3-circuilar inner hole; 4-highly-radiative
material coating layer; 5-rectangular inner hole;
6-highly-radiative material coating layer; 7-highly-radiative
material coating layer; 8-substrate; 9-heat exchange surface;
10-substrate; 11-highly radiative material coating layer; 12-heat
exchange surface; 13-substrate; 14-highly radiative material
coating layer; 15-heat exchange surface.
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1
[0027] As shown in FIG. 1, a heat retainer used for a hot blast
stove of a blast furnace is a checker brick. The checker brick
(heat retainer) has a plurality of circular inner holes 1, and all
surfaces (comprising those of the inner holes) of the check brick
(heat retainer) are coated with a coating layer of a highly
radiative material 2 whose thickness is 0.02 mm. A substrate of the
heat retainer is a refractory material, and the highly-radiative
material coating layer 2 is a highly-radiative material whose
emissivity in the far-infrared region is greater than that of a
substrate material of the heat retainer. The highly-radiative
material coating layer 2 comprises by weight: 110 parts of
Cr.sub.2O.sub.3, 80 parts of clays, 90 parts of montmorillonites,
300 parts of brown corundums, 100 parts of silicon carbides, 400
parts of PA80 adhesive and 100 parts of water. These components are
hyperfinely processed, so as to enable the particle size to be in
the 25-700 nm range. Compared with existent heat exchangers, the
heat exchanger of this embodiment saves over 20% of energy.
Embodiment 2
[0028] As described in embodiment 1, except that differences are as
follows: the cross section of the honeycomb-shaped heat retainer is
rectangular; and the highly-radiative material coating layer is
disposed within a plurality of circular inner holes 3 (as shown in
FIG. 2).
Embodiment 3
[0029] As shown in FIG. 3, the heat retainer for a heat exchange is
fin-shaped. A plurality of rectangular inner holes 5 are disposed
in the heat retainer, and all surfaces (comprising surfaces of the
inner holes) of the heat retainer for the heat exchanger are
paste-coated with a highly-radiative material coating layer 6 whose
thickness is 0.03 mm. A substrate of the heat retainer is a ceramic
material, and the highly-radiative material coating layer 4 is a
highly-radiative material whose far-infrared emissivity is greater
than that of a substrate material of the heat retainer. The
highly-radiative material comprises by weight: 15 parts of
zirconium oxide, 8 parts of Cr.sub.2O.sub.3, 10 parts of TiO.sub.2,
2 parts of montmorillonites, 15 parts of Al.sub.2O.sub.3, 10 parts
of carborundums, 30 parts of PA80 adhesives, and 10 parts of water.
Compared with existent heat exchangers, the heat efficiency of the
heat exchanger according to this embodiment is improved by over
10%.
Embodiment 4
[0030] As shown in FIG. 4, the heat retainer for use in a heat
exchanger according to this embodiment is plate-shaped; and the
surfaces of the heat retainer are paste-coated with a coating layer
7 made of a highly-radiative material and whose thickness is 0.1
mm. A substrate 8 of the heat retainer is an iron and a steel
material, and the highly-radiative material is a highly-radiative
material whose far-infrared emissivity is greater than that of the
substrate material. The highly-radiative material comprises by
weight: 60 parts of Cr.sub.2O.sub.3, 200 parts of brown corundums,
50 parts of clays, 30 parts of montmorillonites, 200 parts of
silicon carbides, 200 parts of hydrated sodium silicate gels, and
100 parts of water. The outer surface of the coating layer 7 is the
heat exchange surface 9. The surfaces of the heat retainer are
coated with a pre-treating liquid prior to being paste-coated with
the highly-radiative material. The pre-treating liquid comprises
10% aqueous solution (by weight) of hydrated sodium silicate gels.
Compared with existent heat exchangers, the heating efficiency of
the heat exchanger of this embodiment is improved by over 10%.
Embodiment 5
[0031] As shown in FIG. 5, the heat retainer for a heat exchanger
is ball-shaped, and the surfaces of the heat retainer are
paste-coated with a highly-radiative material resulting in a
coating layer 11 whose thickness is 2 mm. An outer surface of the
coating layer 7 is the heat exchange surface 12. A substrate 10 of
the heat retainer is a refractory material, and the
highly-radiative material forming the coating layer 11 is a
highly-radiative material whose far-infrared emissivity is greater
than that of a substrate material. The highly-radiative material
comprises by weight: 5 parts of zirconium oxide, 10 parts of
silicon carbides, 5 parts of titanium, 3 parts of clays, 40 parts
of brown corundums, 10 parts of aluminum hydroxides, 15 parts of
phosphoric acid, and 12 parts of water. Compared with existent heat
exchangers, the relative temperature of the heat exchanger of this
embodiment is increased by over 15.degree. C. The heat retainer
according to this embodiment is applicable for use as a
regenerative furnace, in which the ball-shaped heat retainer
exchanges heat within a heat accumulator being part of the
regenerative furnace.
Embodiment 6
[0032] As described in embodiment 5, except that the heat retainer
for a heat exchanger is elliptical in shape (as shown in FIG.
6).
Embodiment 7
[0033] The surfaces of a ball-shaped heat retainer are spray-coated
with a highly-radiative material giving rise to a coating layer
whose thickness is 2.5 mm. The coating layer comprises by weight:
15 parts of silicon carbides, 2 parts of brown corundums, 35 parts
of zirconias, 2 parts of montmorillonites, 6 parts of chromium
oxides, 27 parts of PA80 adhesives and parts of 13 water.
[0034] The surfaces of the heat retainer are coated with
pre-treating liquid prior to being spray-coated with the
highly-radiative material, The pre-treating liquid comprises 10%
aqueous solution (by weight) of PA80 adhesive.
Embodiment 8
[0035] As shown in FIG. 7, the surfaces of a ceramic substrate 13
of a heat retainer are paste-coated with a highly-radiative
material resulting in a coating layer 14 whose thickness is 3 mm.
The outer surface of the coating layer 14 is the heat exchange
surface 15. The coating layer comprises by weight: 60 parts of
Fe.sub.2O.sub.3, 5 parts of zirconias, 20 parts of hydrated sodium
silicate gels and 15 parts of water. The surfaces of the heat
retainer are coated with a pre-treating liquid prior to being
paste-coated with the highly-radiative material coating layer. the
pre-treating liquid comprising a 8% by weight aqueous solution of
hydrated sodium silicate gels.
[0036] The highly-radiative material forming a coating layer on the
heat retainer may be freely selected. The above embodiments are
intended to be illustrative only, and are not meant to limit the
invention.
* * * * *