U.S. patent number RE31,513 [Application Number 06/444,380] was granted by the patent office on 1984-01-31 for blanching, pasteurizing and sterilizing process and apparatus suitable therefor.
Invention is credited to Donald H. G. Glen.
United States Patent |
RE31,513 |
Glen |
January 31, 1984 |
Blanching, pasteurizing and sterilizing process and apparatus
suitable therefor
Abstract
A method is provided which permits continuous and rapid
blanching or sterilization of foodstuffs in particulate form. The
foodstuff is heated rapidly to penetrate the outer portion of the
particle by steam or gas under pressure, the heated particles are
maintained thereunder until inactivation or destruction of
microorganisms and enzymes, after which the pressure and
temperature are lowered rapidly.
Inventors: |
Glen; Donald H. G. (Tumut, New
South Wales, AU) |
Family
ID: |
4211512 |
Appl.
No.: |
06/444,380 |
Filed: |
November 26, 1982 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
011365 |
Feb 12, 1979 |
04255459 |
Mar 10, 1981 |
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Foreign Application Priority Data
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Feb 10, 1978 [CH] |
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1483/78 |
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Current U.S.
Class: |
426/521; 99/471;
99/470; 426/510 |
Current CPC
Class: |
B65B
55/18 (20130101); A23B 7/0053 (20130101); A23B
7/06 (20130101); A23B 4/0053 (20130101) |
Current International
Class: |
A23B
7/005 (20060101); A23B 7/06 (20060101); A23B
7/00 (20060101); A23B 4/005 (20060101); B65B
55/02 (20060101); B65B 55/18 (20060101); A01G
001/04 () |
Field of
Search: |
;426/509,510,521,520
;99/471,470 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Kellogg; Arthur D.
Attorney, Agent or Firm: Steinberg & Raskin
Claims
I claim:
1. A continuous process for the rapid blanching and sterilization
of foodstuffs in particulate form, such as portions of fruit,
vegetables, meat or fish, which comprises continuously moving said
foodstuff particles .Iadd.in a .Iaddend.first .Iadd.zone
.Iaddend.through an elongated pressure chamber where .[.it is.].
.Iadd.the same are .Iaddend.subjected under pressure to hot steam
or gas .Iadd.at a temperature and for a time sufficient .Iaddend.to
rapidly heat the outer portion thereof .[.an.]. .Iadd.and
.Iaddend.to supply .Iadd.thereto .Iaddend.sufficient heat to heat
the foodstuff particles .Iadd.when spread .Iaddend.throughout
.Iadd.the same .Iaddend.to the sterilization temperature thereof,
then moving the thus heated foodstuff particles .Iadd.in a second
zone .Iaddend.through an elongated chamber where the pressure drops
and said particles are maintained under .Iadd.essentially
.Iaddend.adiabatic conditions until the particles attain the
sterilizing temperature throughout for the time necessary to
inactivate or destroy the microorganisms and enzymes .Iadd.and thus
sterilize the food particles.Iaddend., then moving the .Iadd.thus
sterilized .Iaddend.particles of foodstuff .Iadd.in a third zone
.Iaddend.through a cooling unit to effect cooling of the product,
.Iadd.and .Iaddend.moving the cooled product through an enclosed
conveying system to a packing unit where it can be packed
asceptically, .[.all of the.]. movement of the foodstuff particles
being effected at least partly by gravity feed.
2. Apparatus for carrying out the .Iadd.continuous .Iaddend.process
of rapid .[.heat.]. blanching .Iadd.and sterization .Iaddend.of
foodstuff particulates which comprises an elongated .Iadd.gas or
.Iaddend.steam pressure chamber through which the foodstuff first
moves, an adjacent elongated chamber .Iadd.connected to said
pressure chamber and being .Iaddend.under a pressure lower than
.Iadd.that of .Iaddend.said .Iadd.gas or .Iaddend.steam pressure
chamber through which the foodstuff next moves and wherein the
pressure drops while the foodstuff is adiabatically
.[.heated.THETA. .Iadd.equilibrated throughout to the sterilization
temperature thereof, .Iaddend.a cooling unit connected to said
adjacent elongated chamber through which the adiabatically
.[.heated.]. .Iadd.equilibrated and sterilized .Iaddend.foodstuff
then passes and is there cooled, and an elongated enclosed
conveying system connected to said cooling unit and to a packing
unit for conveying the foodstuff to the packing unit, .[.all of.].
said chambers and units being connected and angled to .[.give a.].
.Iadd.effect movement of the foodstuff particles at least partly by
.Iaddend.gravity feed. .Iadd.3. A continuous high-temperature
short-time process for the rapid blanching and sterilization of
foodstuffs in particulate form, such as portions of fruit,
vegetables, meat or fish, which comprises continuously moving said
foodstuff particles through a first zone where the same are
subjected under pressure to hot steam or gas at a temperature and
for a time sufficient to rapidly heat the outer portion thereof and
to supply thereto sufficient heat to heat the particles when spread
throughout the same to the sterilization temperature thereof, then
moving the thus heated foodstuff particles through a second zone
contiguous with said first zone where the pressure drops and said
particles are allowed to equilibrate adiabatically until the
particles attain the sterilization temperature throughout for the
time necessary to inactivate or destroy the enzymes and
microorganisms present, then moving the foodstuff particles through
a third zone contiguous with said second zone to effect cooling of
the product, and then moving the cooled product to a packing unit
connected to said third zone where the said product can be packed
aseptically.
.Iaddend. .Iadd.4. Apparatus for carrying out a continuous
high-temperature short-time process for the rapid blanching and
sterilization of foodstuffs in particulate form which comprises an
elongated pressure chamber having means which support and convey
the particles and means to pass hot steam or gas along said
pressure chamber to provide a first zone through which the
particles first move while being subjected under pressure to hot
steam or gas; an adjacent elongated chamber connected to said
pressure chamber and being under a pressure lower than that of said
pressure chamber to provide a second zone through which the
particles next move and wherein the pressure drops while the
particles are allowed to equilibrate adiabatically whereby the
particles attain a sterilization temperature throughout; a cooling
unit connected to said adjacent elongated chamber to provide a
third zone through which the sterilized particles then pass and are
there cooled; and an elongated enclosed conveying system connected
to said cooling unit and to a packing unit for conveying the
foodstuff to the packing unit. .Iaddend.
Description
This invention relates to method and apparatus for treatment of
fruit and vegetable meat fish and other perishable products in
particulate as well as pulp form using heating and cooling to
preserve such products.
In one modification the invention is especially applicable to the
process of blanching or sterilising of perishable products prior to
containerisation and freezing and wherein the said products are
heated to a particular temperature for a specific period of
time.
By heating the product, the oxygen between the cells, like any gas,
expands and is partially released from the product. Secondly, to
enable the digestive process to occur, enzymes in the form of
catalysts must be present. These are inhibited or destroyed by
raising them above certain temperatures for specific lengths of
time. Thirdly, in the process of canning, blanching has a further
use in that it softens the fibre structure, thus enabling it to be
placed in a can more readily, and the correct "fill weight"
obtained.
Subsequently to blanching the product is either placed in a can,
sealed and sterilised, or frozen and maintained at a temperature
sufficiently low to prevent bacterial growth.
Blanching methods at present in use not only have a tendency to
mechanically damage the product, causing a breakup and product
losses, but also to leach the product of sugars and starches.
Leaching is accentuated under vacuum conditions whereby the esters,
the sugars and the starches are removed but when breaking the
vacuum under steam the cell structure is reformed by replacing the
solution of sugars and starches which have been removed with the
condensate from the steam. This results in possibly an increase in
weight of the product through the blanching process as more water
can be put back than solution taken out, but the taste and the
sugars are not replaced and the quality of the product is damaged,
although the structure is good.
The time in which the product must be subjected to the
abovementioned blanching conditions is dependent on the
conductivity of the product so that the temperature to which the
product is exposed on the outside can penetrate to the middle point
of the product to ensure that the very centre is adequately
blanched. From this, it will be seen that if one considers the
product as a sphere, the outside layer will be subjected to the
blanching temperatures and conditions far longer than that required
to blanch the inside of the product for the outside layer must
remain under these conditions until the very centre has been
blanched, i.e. throughout the time of conduction to the centre.
The invention according to one aspect resides in a continous
process for the rapid or flash blanching of foodstuffs such as
portions of fruit vegetables or perishables which comprises
applying heat rapidly to the external surface of the portions by
means of a hot gas or fluid or a mixture of both passed over the
portions to achieve a mass average temperature and then holding the
heated portions adiabatically in an insulated zone without the
further application of external heat to enable temperature to
equilibrate from the heated external surface of the portions to the
interior part of the portions.
The invention according to another aspect provides a continuous
process for the rapid or flash blanching or sterilisation of
foodstuff particulates under pressure involving high temperature,
short time sterilisation and asceptic packing out of foodstuff
particulates by the application of heat rapidly under pressure and
allowing it to penetrate inwardly adiabatically through
temperatures and pressures within the system and thus holding the
product therein to destroy or reduce the microorganic population
and their rate of fission for preservation and use when
required.
Direct application of high temperature heating media to the
product, under pressure, whilst in transit through the system
within a vibro tube or spiral conveyor down a gradient of from
8.degree. to 15.degree. with the aid of a fluidised bed which is
the vessel for the nesessary heat transferrance to the product so
as to achieve its required specified mass average temperature in
order to sterilise it once equilibrated.
In the second stage the product is then equilibrated to the
required temperature and held for the required time until
commercially sterile.
The thermal time/temperature death curve of microorganisms is
logarithmic and therefore the essence of this process is to raise
the temperature of the product as quickly as possible so as to
balance the external and internal temperatures of the particle with
the view of rapid throughout sterilisation at a temperature which
will least affect the physical chemical and nutritional value of
the product.
Once commercial sterilisation has been achieved the process is
reversed as quickly as possible so as to avoid further
deterioration of the product. The temperature at centre of the
product being the critical factor.
The transfer or conduction of heat in a mass is a function of the
temperature differential (amongst other things) such that the
higher the applied temperature above the initial temperature, the
greater the reduction in time to achieve the desired
temperature.
When latent heat of condensing steam is used to heat the product
particles directly, an insulating later of condensed steam forms on
the surface area of the particle, at a lower temperature and
pressure than that of the steam, and provides as well the
conditions for an osmotic withdrawal of solutions from the product,
through the membranes.
By the removal or non-formation of this later by the use of the
fluidising heat media, the temperature differential can be
maintained, the surface heat transfer increased, conduction in the
mass improved and a substantial reduction in time is obtained.
Further effluent is minimised, and product recovery is
increased.
The conduction of heat is a function of the surface area and the
thickness such that by maintaining the individuality of the product
particles on a thin fluidised bed and using the oscillation
amplitude and gradient to traverse the product, the time of heat
transfer is reduced.
When the time is reduced, as the Thermal, Mechanical Vitamin and
Nutritional colour and osmotic degradation is a function of time
above a base temperature, the quality, the recovery, and the cost
of the product is substantially reduced, and bulk packaging can be
achieved.
Thus the product particle is subjected to the heating conditions at
higher than normal blanching temperatures only until the required
B.T.U.'s have been absorbed into the particle in sufficient
quantity which when universally spread through the particle will
raise it throughout to the required blanching or sterilising
temperature.
In one preferred application of the method of rapid blanching in
accordance with the invention and which is adapted for continuous
blanching and/or pressure sterilizing of fruit vegetables and
perishable products, the product is rapidly passed through a
heating unit whilst spread on a grid belt or the like at a minimal
thickness of, ideally, one particulate deep and a hot gas or fluid
stream of steam or a mixture of both passed through acid over the
pieces and the time taken for it to pass through the heating unit
is only sufficient for it to absorb the correct amount of heat to
raise the total product to the required temperature subsequently in
the holding unit.
The product is then transferred to an insulated holding chamber for
a time sufficient to allow the temperature throughout the product
to reach equilibrium; and equilibrium temperature and time being to
inhibit enzymes and destroy, or reduce the growth rate, of any
microoganisms and release their oxygen. The preferred holding time
is from 11/2 to 5 minutes and no further heat is added during this
time.
According to what may be a preferred feature of a blanching or
sterilising process in accordance with the present invention, the
product temperature in the heating section is obtained by the use
of boiling water sprays or steam.
According to a modification of the process, the hot water sprays in
the initial section of the heating unit are replaced by a dry
combustion fan whose humidity is controlled by the injection of
water vapour to obtain in this section a 10% dehumidification of
the particle on the outside surface which a re-humidified in the
last sections of the heating unit by the absorption from the water
sprays. A further 5% recovery will be gained thereby.
According to a further modification of the inventive process, the
belt or grid on which the product is carried through the heating
section maybe replaced by a fluidised bed system whereby the
product particulates are carried on a stream of hot gas and
condensate through the chamber in a similar manner to that used in
fluidised freezing which will entirely eliminate most all
mechanical damage from the inpingement of the water on the
product.
The invention according to a further aspect provides apparatus for
carrying out the process of rapid heat blanching or sterilising of
foodstuff particulates which comprises a plurality of heat
treatment chambers comprising a first or heat treatment chamber
with means for supporting and conveying the foodstuffs, means for
passing hot gases or gaseous fluid along the chamber and in contact
with the external surfaces of the fruit and a second or thermally
insulated holding chamber for enabling heat from the externally
heated surfaces of the foodstuff particulates to penetrate to the
central region of the foodstuff without further application of
heat.
The invention according to a still further aspect provides
apparatus for carrying out the process of continuous rapid heat
blanching and sterilisation of foodstuff particulates such as fruit
vegetable or protein pieces and which comprises a plurality of
interconnected heat exchanger means for continuously treating said
foodstuff pieces within a series of heat and cool application
treatment and pressure heat and cool holding, heat and cool
penetration treatment zones along the heat and cool exchanger
means, means for feeding foodstuff particulates into the heat
exchanger means, means for conveying the foodstuff along the heat
and cool exchanger means and means for introducing heat and cool
treatment gases or fluid into the exchanger means and in direct
contact with the external surfaces of the foodstuff pieces, and
means for maintaining pressure and temperature in the heat holding
heat penetration zone or zones and means for discharging the
foodstuff particulates without loss of pressure, and means for
asceptically packing out the particulate products.
Preferably the apparatus includes separate means for recycling hot
heat treatment or application gases or fluids from the discharge
end of the first heat treatment chamber or zones to the feed end of
the first heat treatment chamber or zones.
The invention will be further described with reference to the
accompanying drawings in which:
FIG. 1 is a diagrammatic representation of apparatus in accordance
with the present invention.
FIGS. 2A and 2B represent side-elevation views of two embodiments
of the In-Feed unit of the apparatus of the present invention;
FIG. 3 is a side elevation view of the Pre-Heat Float Feed Control
Chamber and the Heat Units;
FIG. 4 is a side elevation view of the Adiabatic Equilibrating,
Inactivating and Flash-off unit;
FIG. 5 is a side elevation of the Flash-off Float Feed Control
Chamber and the Cool Unit incorporating a gas closed circuit;
FIG. 6 is a side elevation of the Out-Feed Unit;
FIGS. 7a and 7B represent two embodiments of the asceptic
Filler-Isolator or packing out unit;
FIG. 8 is representative of a standard heat balance applicable to
the process in accordance with the present invention;
FIGS. 9A and 9B are representative of the Heat and Cool thermal
conductivity Time/Temperature, Curves applicable to a preferred
embodiment in accordance with the present invention.
Referring to FIG. 1 the product is fed into the apparatus from an
elevator-controller, which delivers a specified volume at specific
intervals directly into the in-feed unit 10 of the apparatus, whose
operation it controls. The in-feed unit, by a pressure equalising
device and cycled valve operation, feeds the product into the
pressurised system within the apparatus against the operating
pressure.
A pre-heat unit 11 is interposed between the in-feed unit 10 and
the heat unit 12 to act as a float chamber from which the heat unit
draws the product at a constant rate and layer thickness onto the
perforated carrier plate 13. The heat unit 12 raises the
temperature of the product to the mass average temperature needed
for short time sterilization and inhibition of enzymes. The heat
unit comprises a vibro tube or spiral conveyor set at an angle of
about 8.degree. to 15.degree. to the horizontal with a perforated
support or carrier plate 13 extending axially throughout the
tubular heat unit, along which the product travels at minimal layer
thickness or depth by oscillation on a fluidized bed provided by
the heating media of steam/gas passing through the perforated
support plate 13 to the product and transmitting to it sufficient
heat to raise the particulate mass average temperature to that
called up by the standard data. The heating media used is a
steam-gas mix which maintains the applied temperature differential,
eliminates the insulating surface layer of condensed steam, and the
osmotic withdrawal of the solutions in the product, improving to
conductivity to achieve a short heating time.
The heat unit 12 is connected to the adiabatic equilibrating unit
14 via flexible connection bellows 15 and slopes away from the heat
unit at an angle of about 5.degree. to the horizontal. The
equilibrating unit comprises first and second equilibrating
chambers (16 and 18, respectively), first and second pressure drop
chambers (17 and 19, respectively), and an inactivating chamber 20.
The equilibrating unit receives the product at mass average
temperature and during its transit through this unit allow the
temperature to equilibrate to the centre and throughout from the
mass average temperature, holding it at this temperature to inhibit
or destroy the microorganisms and enzymes, such that the product is
sterilised to a commercially acceptable level. At the same time it
drops the pressure from the maximum for mass average temperature to
the equilibrated temperature and pressure.
The pressure differential flash off chamber 21 receives the product
from the equilibrating unit and partially cools it by `flashing
off` by dropping the pressure. This chamber also acts as a float
chamber from which the cooling unit 22 draws the product at a
constant rate and layer thickness.
The cooling unit 22 lowers the mass average temperature to that
required for thermal and mechanical stability. The cooling unit is
a similar unit to the heat unit 12, operating on the same
principle, save that the heating steam/gas media is replaced by a
cooling gas in closed circuit through a heat exchanger, de-waterer,
and bacteria filter. Under certain circumstances, and for certain
products, a bleed in of atomised refrigerant is used to obtain a
lower applied temperature.
The out-feed unit 23 receives the product from the cooling unit 22,
acting as a float and pressure drop chamber and equilibrating the
product at the same time.
The asceptic packing out unit 24 of filler-isolator receives the
product for packaging under inert and sterile conditions.
FIGS. 2a and 2b show details of alternatives for the in-feed unit
10. The unit comprises a pressure lock chamber 25 with
automatically operated inlet and outlet valves (26 and 27,
respectively) into which the gas to partially dehydrate the product
is fed via conduit 28, at the same time providing an additional
force to drive the product out of the chamber and down the pre-heat
unit.
Referring to FIG. 3 the pre-heat float feed control chamber
comprises a stainless steel tube 30 through which the product
passes to partially dehydrate the surface with a valve 31 at the
base which varies the outlet orifice in relation to the height 32,
thus controlling the outflow pattern and the depth of the product
on the heat unit carrier plate. The heat unit comprises a stainless
steel pressure tube or cylinder 33, which is vibrated by
out-of-balance motors or vibro-magnets 34, the tube being set at an
angle to the horizontal, providing a transporting oscillation on
the perforated carrier plate 35, which is fixed in the same plane
as the tube. The heating media is fed into the tube at the bottom
36, passing up through the carrier plate and fluidising the
product. It is drawn out by ejectors 37, having lost part of its
latent heat, in a super-saturated condition, is reheated in the
ejectors by the steam supply, and by exhaust burner gases and
re-cycled.
Some liquid condensate is passed out through the drain 38 and is
either carried forward with the product, or lost to sink at 39.
FIG. 4 illustrates more detail of the adiabatic equilibrating,
inactivating and flash off unit sections of apparatus illustrated
in FIG. 1. The equilibrating unit comprises first and second
equilibrating chambers 16 and 18, first and second pressure drop or
release chambers 17 and 19 with outlets 45. The pressure release
chambers have an inner perforated chamber 43 to facilitate gas
permeation. The second pressure release chamber is connected to the
inactivating chamber 20, which in turn is connected to the flash
off feed control chamber 21 which comprises an inner perforated
annular chamber 46 which releases the pressure to the outer annular
chamber 47, the pressure in which is controlled by a release valve
48. At the lower end of the flash off chamber a valve 49 varies the
outlet orifice in relation to the height 32 (FIG. 3), thus
controlling the outflow pattern and the depth of the product on the
carrier plate of the cooling unit 22 (FIG. 1).
Referring to FIG. 5 the cooling unit 22 comprises a stainless steel
cyindrical tube 33 which is similar in design and operation to the
heat unit illustrated in FIG. 3. (especially items 33, 34 and 35
thereof), but the heating media is replaced by a cooling carrier
gas, which is inert and sterile, and is fed into the cylindrical
chamber 33 via inlets 54 to maintain an approximate 0.degree. . C.
temperature at the product surface on the perforated carrier plate
52, fluidising the product, and absorbing heat from it.
The inert sterile cooling media carrier gas is in closed circuit,
passing into the cooling unit, via conduit 51 and inlets 53, at a
temperature of approximately 0.degree. C.; the carrier gas then
passes through the perforated carrier plate 52, and the product
thereon, fluidising the product and absorbing heat therefrom. The
carrier gas then passes out of the cooling unit via conduit 54 at a
temperature of approximately 75.degree. C., through a de-waterer
55, and a bacteria filter 56, to the heat exchanger 57, and back to
the pump or fan 58. Before re-entering the cooling unit, the
carrier gas receives a boost charge of atomised liquified gas from
conduit 59. The atomised liquified gas is at a temperature of
-80.degree. to -196.degree. C., depending on the gas used, to
reduce the temperature of the gas re-entering the cylindrical
chamber 33 to approximately 0.degree. C., to maximise the
temperature differential and thus the conduction, as well as the
discharge from the out-feed unit 23 (FIG. 1). Alternatively, the
cooling unit can be used as the evaporator in a refrigeration
cycle, in conjunction with a compressor and condensor.
Referring to FIGS. 3 and 5 the cylindrical chambers of both the
heat unit and the cooling unit have quick opening end plates 80 for
inspection and maintenance.
FIG. 6 illustrates more detail of the out feed unit 23 of the
apparatus illustrated in FIG. 1. The out feed unit comprises a
perforated inner cylinder 60, which releases the pressure to
slightly above atmospheric to an outer annular chamber 61, the
pressure in which is controlled by release valves 62, and thence
back into the closed circuit via the bleed in system shown at
63.
FIGS. 7a and 7b illustrate alternative forms of the asceptic
packing out unit or filler-isolator. The embodiment illustrated in
FIG. 7a is a well-type unit for heavier than air products and the
embodiment illustrated in FIG. 7b is a diving bell type unit for
lighter than air products. The gas inlet and gas outlet are
represented by 70a and 70b, respectively. The product enters the
packing out unit from the out-feed unit via the conduits 78. The
carton or bag to be filled enters the packing out unit from the
left-hand side, and the filled bags or cartons leave the packing
out unit from the right hand side. In FIG. 7a there is an overhead
rail system 81 along which carrier means 82 can run. The carrier
means transport bags 83 via the ultra-violet (U.V.) light
resterilisation station 74 (with overhead U.V. light source 75),
the filling station 76 under the conduits 78, and the sealing
station 77. The whole filling or packaging operation can be
observed through observation window 72 and glove ports 71 allow for
any required manual operations. In FIG. 7b there is a conveyor
means 84 to convey cartons 85 through the packing out unit via the
U.V. resterilisation station 74, the filling station 75 and the
sealing station 77.
In FIG. 8 an example is given of a specific standard heat balance
where the product heat (Qp) is taken at 800,000 Kilojoules/hour,
the steam supply pressure (SI,HI) is taken at 1,000 kpa and the
transfer takes place in conformity with the selected standard
conduction graphs at 150.degree. C. and 380 Kpa to achieve a Mass
average temperature of 133.degree. C. (ref FIG. 9a). It is upon
this that a computer program is written to provide a standard data
heat balance for each product and product size and diffusity
etc.
In FIG. 8 the steam is supplied at 1000 Kpa (A1) to the ejector (3)
which withdraws the super-saturated exhaust from the heat unit,
carrying with it globules of liquid (2) in the gas (1). A reheat of
exhaust gas is supplied (4) from the burner (Bi), discharging to
the underside of the carrier plate in the heat unit (8).
In FIG. 8 steam at 1000 Kpa is also supplied at option (A2) to an
ejector (6) drawing from the condensate drain of the heat unit, and
discharging it (7) through an exhaust gas reheat ejector (B2) to
the underside of the carrier plate of the Heat Unit (8).
An optional portion of the drain of condensate is passed through to
the equilibrating unit and the product at (Y) carrying with it a
portion of the product heat (Qp2).
The product is discharged at (X) with the addition of (Qp1) such
that the product is received into the equilibrating unit at
(Z)=(X+Y)=(Qp). It should be noted that it is not necessary for
both cycles to be used, together.
__________________________________________________________________________
CYCLE HEAT BALANCE (Example) A1. From Bir Steam 114 kg/Hr 930 Kpa
2784 hg = 317401 kJ/hr at 175.degree. C. 1. From Re-Circ Vap 110
Kg/Hr 482 Kpa 2758 hg = 303406 kJ/hr at 150.degree. C. 2. From
Re-Circ Lqd 114 Kg/Hr 482 Kpa 636 hg = 72488 kJ/hr 150.degree. C.
3. From Total wet mix 338 Kg/Hr 551 Kpa -- = 693295 kJ/hr at
160.degree. C. B1. From Burner (4.77) Kg/Hr 50917 hg = 242874 kJ/hr
at --.degree. C. 4. From Total Dry Vap 338 Kg/Hr 551 Kpa hg =
936069 5. From ink drain Lqd 105 Kg/Hr 551 Kpa 2764 hg = 69141
kJ/hr at 150.degree. C. A2. From Blr Steam 105 Kg/Hr 930 Kpa 2781
hg = 292009 kJ/hr at 175.degree. C. 7. From Totl. Wet Mix 210 Kg/Hr
551 Kpa -- = 361150 kJ/hr at 155.degree. C. B2. From Burner (4.3)
Kg/hr. 59017 hg = 218945 kJ/hr at --.degree. C. 8. From TOTAL INPUT
546 Kg/Hr 551 Kpa 2774 hg = 1516164 kJ/hr at 160.degree. 0. X. To
Qp - Heat (3000 Kg/hr) 800000 kJ/hr at 133.degree. C. Y. To
QP:Equi-6% wt 180 Kg/Hr 482 Kpa 668 hg = 120245 kJ/hr at
155.degree. C. Z. To Total Qp (3200 Kg/Hr) = 920245 kJ/hr at
133.degree. C. MAT L. To Losses & work say 10% of 8. above 5.
To Sink drain Recirc 105 Kg/Hr 551 Kpa 663 hg = 69140 Kj/hr at
150.degree. C. 1. To Vap Recirc 110 Kg/Hr 482 Kpa 2758 Kg = 303406
kJ/hr at 150.degree. C. 2. To Lqd Recirc 114 Kg/Hr 482 Kpa 636 hg =
72488 kJ/hr at 150.degree. C. TOTAL OUTPUT 15167344 at TOTAL HEAT
BALANCE (Example) IN. A. Total Steam A1 = 114 Kg at 930 Kpa 2784 hg
= 317402 kJ/hr A2 = 105 Kg at 930 Kpa 2784 hg = 292009 kJ/hr TOTAL
A 219 Kg at 930 Kpa 2784 kg = 609411 kJ/hr B. Total Burner B1 =
(4.77) Kg 50917 hg = 242874 kJ/hr B2 = (4.3) Kg 50917 hg = 218945
kJ/hr TOTAL B = (9.1) Kg 50917 hg = 46189 TOTAL INPUT =1071230
kJ/hr OUT Qp - heat (x) = 800000 kJ/hr Qp - Equil (Y) = 121245
kJ/hr 920245 kJ/hr Allow losses = 151455 & work TOTAL OUTPUT
10717007 kJ/hr
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FIGS. 9a and 9b illustrate examples of the computer drawn Standard
family of product graphs for heating time and temperature with
adiabatic times and temperatures (9a) and cooling times and
temperatures (9b) for an acidic product. Each family of graphs are
drawn for a media supply temperature (Ts) and a particular product
size and diffusity and initial temperature (Ti). Each graph in the
family is drawn for a Heat or Cool time (t) in seconds to show the
product centre temperature (tpc) achieved on the co-ordinate
against the equilibrating time in seconds on the ordinate axis on a
logarithmic scale (te).
Although the invention has been described above with reference to
preferred embodiments, examples and drawings, it will be
appreciated that numerous variations, modifications or alternatives
may be substituted for specifically described features, without
departing from the spirit or scope of the invention as broadly
described.
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