FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
As amended by the Patents (Amendment) Act, 2005
&
The Patents Rules, 2003
As amended by the Patents (Amendment) Rules, 2006
COMPLETE SPECIFICATION
(See section 10 and rule 13)


TITLE OF THE INVENTION
A continuous method and a system for processing paddy
APPLICANTS
Kilbum Engineering Limited, Bhandup West, Mumbai 400 078, Maharashtra, India, an Indian Company
INVENTOR
Arora Premkumar Kartarsingh, Kilbum Engineering Limited, Bhandup West, Mumbai 400 078, Maharashtra, India, an Indian National
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the nature of this invention and the manner in which it is to be performed:


FIELD OF THE INVENTION
This invention relates to a continuous method and a system for processing paddy.
BACKGROUND OF THE INVENTION
Paddy freshly harvested from the field generally has a moisture content of 20 to 25% Wet Basis and contains undesirable foreign particles like chaff, pieces of stalk, stones, soil or dust. Prior to milling and polishing, freshly harvested paddy mass is processed in order to reduce breakage and losses and retain the nutritious value and to increase the storage life. Paddy is first cleaned by extracting the foreign particles from the paddy mass by screening and aspiration. Cleaned paddy is parboiled by presteaming the paddy, hot water soaking the paddy, draining out water from the paddy, steam cooking the paddy and drying the paddy prior to milling and polishing. During cooking, getlatinisation of starch in the rice grains takes place. This helps to harden the grains during drying and reduce breakage of the grains and losses during milling and polishing. If the paddy is not uniformly cooked and dried, it becomes powdery when stored for a long period of time. Hot water soaking is carried out generally at 55 to 60 °C during which the moisture content of the paddy mass increases to 30 to 34% WB. Cooking is carried out with steam generally at 85 to 100 °C in a batchwise manner in a cooking vessel fitted with manually operated feed inlet valve, cooked paddy outlet valve and steam inlet valve. During cooking, steam is injected into the paddy mass from the top and through the center of the paddy mass. Parboiled paddy has a moisture content of 36-37% WB and is usually dried in a LSU (Louisiana State University) dryer which basically comprises a rectangular vessel. Feed rate of paddy into the dryer is controlled through a rotary feeder provided at the bottom thereof. Paddy is dried by circulating the paddy mass in the dryer from bottom to top of the dryer with the help of a mechanical elevator. Baffles are

provided in the dryer to allow hot air being blown into the dryer to contact the paddy mass during circulation. Usually the paddy mass is dried to a moisture content of 12 to 14 % WB in a LSU dryer. The extent of drying in a LSU dryer will depend upon the number of passes of the paddy mass in the dryer from bottom to top. Usually 6 to 8 numbers of passes are required to dry the paddy mass to a moisture content of 12 to 14% WB in a typical LSU dryer. Since the paddy mass is parboiled batchwise, drying of the parboiled paddy mass is also carried out in the LSU dryer in a batchwise manner. As a result of the batchwise operation, a long time is required for parboiling and drying the paddy mass and productivity is reduced. Also the dryer capacity is not fully utilized. During cooking, since steam is injected only from the top of the paddy mass through the center of the paddy mass the paddy mass is not uniformly cooked at the outer layers thereof as steam does not penetrate into the outer layers at the periphery of the paddy mass uniformly. This also leads to non-uniform drying of the paddy mass. Non-uniform cooking and drying will increase the breakage and losses and reduce the output and also the nutritious value of the milled and polished paddy. Removal of husk during milling also becomes difficult. Manual operation of the cooking vessel is also inconvenient and cumbersome to carry out. Further thermal energy requirement of the dryer for drying the paddy mass is high."
OBJECTS OF THE INVENTION
An object of the invention is to provide a continuous method for processing paddy, which method reduces the processing time of paddy and breakage and losses of paddy and increases the productivity and retains the nutritious value of the paddy and increases the storage life of the paddy.

Another object of the invention is to provide a continuous method for processing paddy, which method is energy efficient.
Another object of the invention is to provide a continuous system for processing paddy, which system reduces the processing time of paddy and breakage and losses of paddy and increases the productivity and retains the nutritious value of the paddy and increases the storage life of the paddy.
Another object of the invention is to provide a continuous system for processing paddy, which system is energy efficient.
Another object of the invention is to provide a continuous system for processing paddy, which system is simple in construction and easy and convenient to operate.
DETAILED DESCRIPTION OF THE INVENTION
According to the invention there is provided a continuous method for processing paddy, wherein cleaned, presteamed, hot water soaked and water drained paddy mass is continuously and uniformly steam cooked and continuously predried prior to drying.
According to a variation of the method of the invention, cleaned, presteamed, hot water soaked and water drained paddy mass is continuously and uniformly steam cooked in an automated steam cooker by automatically controlling the feed rate of the water drained paddy mass into the steam cooker and the discharge rate of steam cooked paddy mass

from the steam cooker and by automatically controlling the steam feed rate into the steam cooker to maintain a cooking temperature of 95 to 100°C and a pressure of 1000 mmwc to 1500 mmwc in the steam cooker and by simultaneously injecting steam through the center of the water drained paddy mass radially outwardly and by injecting steam from the periphery of the water drained paddy mass radially inwardly along the entire height of the paddy mass.
According to a variation of the method of the invention, the steam cooked paddy mass is continuously predried in two stages. According to a variation of the method of the invention, the steam cooked paddy mass is predried by forcing atmospheric air through a bed of the paddy mass and simultaneously moving the bed of paddy mass forward under the force of the atmospheric air followed forcing hot air through a bed of the atmospheric air predried paddy mass and moving the bed of paddy mass forward under vibration of the bed of paddy mass and force of the hot air.
According to the invention there is also provided a continuous system comprising an automated steam cooker for steam cooking cleaned, presteamed, hot water soaked and water drained paddy mass continuously and uniformly and a predrying arrangement for predrying the steam cooked paddy mass prior to drying thereof.
According to an embodiment of the invention, the automated steam cooker comprises a plurality of spaced perforated cooking chambers surrounded by a steam jacket in spaced apart relationship therewith and connected to a water drained paddy inlet through feed inlet passages at the top thereof and connected to a steam cooked paddy discharge outlet at the bottom thereof, each of the perforated cooking chambers being provided with a

centrally located perforated steam injector tube, the water drained paddy inlet being provided with a feed rate metering device and the steam cooked paddy discharge outlet being provided with a discharge rate metering device, the steam jacket being provided with a steam inlet, the steam inlet and the steam injector tubes being connected to a steam source through a steam control valve, the feed rate metering device and the discharge rate metering device and the steam control valve being connected to a logic control automatically to control the water drained paddy feed rate through the water drained paddy inlet and cooked paddy discharge rate through the steam cooked paddy discharge outlet and the steam inflow rate through the steam control valve and maintain a cooking temperature of 95 to 100°C and a pressure of 1000 to 1500 mmwc within the cooking chambers.
According to an embodiment of the invention, the predrying arrangement comprises a stationary atmospheric air predrying unit and a vibratory hot air predrying unit. According to an embodiment of the invention, the stationary atmospheric air predrying unit comprises an atmospheric air predrying chamber having a perforated bottom and a feed hopper at the inlet end thereof and a discharge outlet at the discharge end thereof, the predrying chamber being connected at the top thereof to an air exhaust chimney through atleast one cyclone separator and the bottom of the predrying chamber being connected to a forced atmospheric air blower through air inlet passages provided with air control valves to allow atmospheric air to flow through the air inlet passages and corresponding perforations in the bottom of the predrying chamber in a progressively reducing manner and create progressively reducing air pressure zones from the inlet end to the discharge end of the predrying chamber to take away the heat and moisture of the steam cooked paddy mass and to move the paddy mass forward and the vibratory hot air predrying unit

comprises a hot air predrying chamber provided with a feed hopper at the inlet end thereof, a discharge outlet at the discharge end thereof and an exhaust air outlet, the hot air predrying chamber further comprising a vibratory plenum chamber comprising a channel member extending along the length of the hot air predrying chamber and connected to a forced hot air blower, the channel member being supported on a hollow support structure with the help of springs and adapted to describe a sinusoidal movement in the forward direction, the channel member comprising a plurality of openings along the length of the base thereof and the vibratory plenum chamber further comprising drive means connected to the support structure to impart sinusoidal movement to the plenum chamber.
According to an embodiment of the invention, the drive means comprises an electric motor having a driver pulley mounted on the shaft thereof, a driven shaft disposed parallel to the motor shaft and rotatably mounted on a pair of spaced apart upright members, a driven pulley mounted on the driven shaft at one end thereof corresponding to the driver pulley on the motor shaft, the driver and driven pulleys being interconnected by a belt, a cam provided on the driven shaft and a cam follower engaged over the cam and connected across the support structure through a cross connector means.
According to an embodiment of the invention, the cam follower comprises a first bearing and the cross connector means comprises a crosspin rigidly connected across a bracket which in turn is connected across the support structure and a second bearing mounted on the crosspin and coupled to the first bearing.

The following is a detailed description of the invention with reference to the accompanying drawings, in which:
Fig 1 is a flow diagram of the continuous system for processing paddy according to an embodiment of the invention;
Fig 2 is a partly cut isometric view of the automated steam cooker of the system of Fig 1;
Fig 3 is an isometric view of a perforated steam injection tube of the steam cooker of Fig 2;
Fig 4 is a block diagram of the feed rate metering device, discharge rate metering device and steam control valve and the programmable logic control (PLC) of the automated steam cooker of Fig 2;
Fig 5 is an elevation of the stationary atmospheric air predrying unit of the system of Fig l;
Fig 6 is a scrap view of the perforated bottom of the predrying chamber of the predrying unit of Fig 5;
Fig 7 is an isometric view of the vibratory hot air predrying unit of the system of Fig 1;
Fig 8 is an isometric view of the plenum chamber of the predrying unit of Fig 7;

Fig 9 is anenalarged view of part of the base of the plenum chamber of Fig 8;
Figs 10, 11 and 12 are elevation, plan view and side view of the drive means of the
predrying unit of Fig 7; and
Fig 13 is a crossectional view of the driven shaft of the drive means of Figs 10, 11 and 12.
The continuous system 1 for processing paddy as illustrated in Figs 1 to 13 of the accompanying drawings comprises an automated steam cooker 2 for cooking cleaned, presteamed, hot water soaked and water drained paddy mass continuously and uniformly. The steam cooker comprises four spaced perforated cooking chambers 3 surrounded by a steam jacket 4 in spaced apart relationship therewith and connected to a water drained paddy inlet 5 through feed inlet passages 6 at the top thereof and connected to a steam cooked paddy discharge outlet 7 at the bottom thereof (Figs 1 and 2). Perforations of the cooking chambers are marked 3a. Each of the perforated cooking chambers is provided with a centrally located perforated steam injector tube 8 (Figs 2 and 3). Perforations in the tubes 8 are marked 8a. The water drained paddy inlet 5 is provided with a feed rate metering device, preferably a rotary valve 9. The steam cooked paddy discharge outlet 7 is provided with a discharge rate metering device, preferably a rotary valve 10. The steam jacket 4 is provided with a steam inlet 11. The steam inlet and the steam injector tubes are connected to a steam source (not shown) through a steam control valve 12. Ducts connecting the steam control valve to the steam inlet 11 and the four steam injector tubes 8 are marked 13 and 14a, 14b, 14c and 14d, respectively (Fig 4). The feed rate metering device and the discharge rate metering device and the steam control valve are connected to a logic control circuit, preferably a programmable logic control (PLC) 15. 16 is an inspection window provided with the steam jacket. The steam cooker is provided

with condensate outlet 17 to allow steam condensate in the steam cooker to flow out. The feed inlet passages 6 at the top of the steam cooker diverge toward the cooking chambers and the steam cooker converges at the bottom thereof to facilitate feed entry into the steam chambers and to converge the steam cooked paddy being discharged from the steam cooker, respectively. The continuous system further comprises a predrying arrangement including a stationary atmospheric air predrying unit 18 and a vibratory hot air predrying unit 19 for continuously predrying the steam cooked paddy prior to drying thereof Trie stationary atmospheric air predrying unit 18 comprises an atmospheric air predrying chamber 20 having a perforated bottom 21 (Figs 5 and 6). Perforations in the bottom are marked 22. The predrying chamber is provided with a feed hopper 24 at the inlet end thereof and a discharge outlet 25 at the discharge end thereof. The predrying chamber is connected at the top thereof to an air exhaust chimney 26 through a cyclone separator 27. The bottom of the predrying chamber is partitioned into progressively reducing air pressure zones by air inlet passages 29 which are connected to a forced atmospheric air blower 30. The air inlet passages are provided with control valves 31. The vibratory hot air predrying unit 19 comprises a hot air predrying chamber 33 provided with a feed hopper 34 at the inlet end thereof, a discharge outlet 35 at the discharge end thereof and an exhaust air outlet 36 (Fig 7). The predrying chamber 33 further comprises a vibratory plenum chamber comprising a channel member 37 extending along the length of the drying chamber and connected to a forced hot air blower 41. The base and sidewatfs of the channel member are marked 37a and 37b. Channel member is supported on a hollow support structure 38 with the help of springs, preferably steel springs 39 and adapted to describe a sinusoidal movement in the forward direction as explained hereinbelow. Heater elements at the inlet end of the hot air blower are marked 42. The channel member comprises a plurality of openings 43 along the length of

the base thereof (Figs 8 and 9). 45 is a drive means comprising an electric motor 46 having a driver pulley 47 mounted on the shaft 48 thereof. 49 is a driven shaft disposed parallel to the motor shaft and rotatably mounted on a pair of spaced apart upright members 50, 50. 51 is a driven pulley mounted on the driven shaft at one end thereof corresponding to the driver pulley on the motor shaft. The driver and driven pulleys are interconnected by a belt 52. The driven shaft is integrally formed with a cam profile 53. 54 is a first bearing mounted over the cam profile of the driven shaft. 55 is a crosspin mounted across a bracket 56 which in turn is mounted across the support structure 38. 57 is a second bearing mounted on the crosspin and coupled to the first bearing through a coupler 58. 59 is an access window for cleaning the support structure and channel member base from inside (Fig 8). 60 is a water drained paddy feed hopper located above the automated steam cooker (Fig 1).
During working of the continuous system of the invention, cleaned, presteamed, hot water soaked and water drained paddy mass (not shown) is continuously fed into the steam cooker 2 via the feed hopper 60. Steam (not shown) is injected into the perforated cooking chambers 3 of the steam cooker via steam control valve 12 and the steam inlet 11 and the perforated steam injector tubes 8 so as to maintain a cooking temperature of 95 -100°C and a pressure of 1000 to 1500 mmwc in the cooking chambers. The paddy feed rate and steam inflow rate into the steam cooker and the cooked paddy discharge rate from the steam cooker are controlled by the PLC through the respective valves so as to allow a residence time for the paddy mass within the cooking chambers and allow the paddy mass to be continuously cooked and discharged. Steam being injected through the perforations 8a of the steam injector tubes 8 radially outwardly and steam in the steam jacket 4 being injected into the paddy mass radially inwardly through the perforations 3a

of the perforated cooking chambers 3 ensure uniform cooking of the paddy mass in the cooking chambers across the entire height of the paddy mass. The cooked paddy mass is continuously fed into the atmospheric air predrying chamber 20 of the stationary atmospheric air predrying unit 18 via the feed hopper 24. The paddy mass falls on the perforated bottom of the predrying chamber 23 and forms a bed. The air control vlaves 31 in the air inlet passages 29 of the bottom chamber 2\ of the predrying chamber 20 are so set as to allow the atmospheric air being blown by the blower 30 to pass through the air inlet passages in a progressively reduced manner. Therefore, the atmospheric air enters the predrying chamber through the perforated bottom thereof with air pressures in a progressively decreasing manner so as to create at the bottom of the predrying chamber air pressure zones in a progressively reducing manner from the JnJer end to the discharge end of the predrying chamber 20 and to take away the heat and moisture of the steam cooked paddy mass and to move the paddy mass forward. The atmospheric air predried paddy mass is discharged through the discharge outlet 25 of the predrying unit 20. The air in the predrying unit is exhausted into the atmosphere through the chimney 26 via the cyclone separator 27. While passing through the cyclone separator, foreign particles like chaff, fibre or dust from the paddy mass getting transferred into the air are trapped by the cyclone separator and are collected from the cyclone separator. The atmospheric air predried paddy mass being discharged from the predrying unit 20 falls into the vibratory plenum chamber 37 of the hot air predrying unit 19 via the feed hopper 34 at the inlet end thereof. During operation of the hot air predrying unit, the motor shaft 48 rotates and transmits the drive to the driven shaft 49 via the driver and driven pulleys 47 and 51 and belt 52 and causes the driven shaft 49 to rotate. Due to rotation of the driven shaft, the bearing 54 describes a smooth and gentle up and down rotational movement over the cam profile 53 of the clriven shaft resembling motion along a smooth curvature or a sinewave

in the forward direction. As a result, the second bearing 57 along with crosspin 55, bracket 56, hollow support structure 38 and plenum chamber 37 describes a sinusoidal movement in the vertical plane in the forward direction. The paddy mass being fed into the plenum chamber spreads on the base of the plenum chamber and forms a bed. Hot air being blown by the blower 41 through the openings 43 at the base of the plenum chamber lifts up the grains of the paddy mass slightly and also turn or swing them around. The air bubbles through the grains and comes in contact with all the gains and all around the grains. The hot air flow is controlled so as to give a forward momentum to the grains. As a result of the sinusoidal vibratory movement of the plenum chamber and the force of the incoming hot air, the grain mass move forward on the plenum chamber like a fluidized bed with practically no friction. There is intense heat and mass transfer and heat and moisture is removed from the grains very effectively and the grains are predried uniformly and very fast during their forward movement along the plenum chamber. Hot air predried grain mass is continuously discharged through the discharge outlet 35 of the predrying unit 19. The air is let out into the atmospheric via the exhaust air outlet 36 of the predrying unit 19. The sidewalls 37b of the plenum chamber prevent the grain mass from falling down from the sides of the plenum chamber while moving forward on the base of the plenum chamber. The steel springs give flexibility to the plenum chamber to vibrate and describe the sinusoidal motion but at the same time hold the plenum chamber firmly. The predried paddy is dried in a dryer like LSU dryer. Preferably the temperature of the hot air is set to 100 tol 10°C. Preferably the steam cooked paddy mass is predried to a moisture content of 18-20% Wet Basis.
According to the invention cleaned, presteamed, hot water soaked and water drained paddy is continuously and uniformly steam cooked and continuously predried prior to

drying. Due to uniform cooking starch in the grains is uniformly gelatinised and the grains are uniformly hardened during predrying and drying. Thermal energy requirement for final drying of the paddy mass is considerably reduced and the dryer used for final drying of the paddy mass can be continuously used to full capacity. Due to the continuous processing operation, processing time is substantially reduced and processing efficiency and productivity are considerably increased. Breakage of grains and losses are reduced, output or yield is improved and nutritious value of the paddy is retained. During milling dehusking is also easily achieved. There is also saving in thermal energy during predrying because of the use of ambient air for predrying. The system of the invention is also simple in construction and easy and convenient to operate.
The invention is essentially in continuously and uniformly steam cooking cleaned, presteamed, hot water soaked and water drained paddy mass and in continuously predrying the steam cooked paddy mass prior to drying. The above embodiment is only illustrative of the invention and not limitative of the scope thereof. There can be different embodiments of the invention obvious to those skilled in the art and falling within the scope of the invention. The configuration and construction of the automated steam cooker can be different. The feed rate metering device and the discharge rate metering device need not be rotary valves. Instead of PLC, any other logic control can be used to control the feed rate and discharge rate of the paddy and to control the steam inflow rate. The number of cooking chambers can vary. There can be one or more than one cyclone separator. The cam profile need not be integrally formed with the driven shaft. The cam follower need not a bearing. The construction and configuration of the atmospheric air predrying unit and hot air predrying unit can be different. Instead of predrying the cooked paddy mass in two stages it can be predried in a single stage using a different

predrying arrangement. Instead of using atmospheric air for predrying, hot air at a
different temperature also can be used for predrying the paddy mass. Use of
atmospheric air for predrying renders the invention energy efficient. The drive means for the plenum chamber can be of a different configuration or construction. The cam follower comprising a bearing will ensure smooth and friction free rotation and reduce wear and tear to the cam profile. The second bearing is optional but because of the second bearing the load on the crosspin 55 is effectively borne by the second bearing and damage to the crosspin is minimized. It also gives certain amount of flexibility to the crosspin. As a result, the life of the cross pin is increased. The construction and configuration of the plenum chamber also can vary. Such variations of the invention are obvious to those skilled in the art and are to be construed and understood to be within the scope of the invention.

We claim:
1. A continuous method for processing paddy, wherein cleaned, presteamed, hot water soaked and water drained paddy mass is continuously and uniformly steam cooked and continuously predried prior to drying.
2. The method as claimed in claim 1, wherein cleaned, presteamed, hot water soaked and water drained paddy mass is continuously and uniformly steam cooked in an automated steam cooker by automatically controlling the feed rate of the water drained paddy mass into the steam cooker and the discharge rate of steam cooked paddy mass from the steam cooker and by automatically controlling the steam feed rate into the steam cooker to maintain a cooking temperature of 95 to 100°C and a pressure of 1000 mmwc to 1500 mmwc in the steam cooker and by simultaneously injecting steam through the center of the water drained paddy mass radially outwardly and by injecting steam from the periphery of the water drained paddy mass radially inwardly along the entire height of the paddy mass.
3. The method as claimed in claim 1 or 2, wherein the steam cooked paddy mass is continuously predried in two stages.
4. The method as claimed in claim 3, wherein the steam cooked paddy mass is predried by forcing atmospheric air through a bed of the paddy mass and simultaneously moving the bed of paddy mass forward under the force of the atmospheric air followed forcing hot air through a bed of the atmospheric air predried paddy mass and moving the

bed of paddy mass forward under vibration of the bed of paddy mass and force of the hot air.
5. The method as claimed in claim 4, wherein the temperature of the hot air is 100 to 110°C.
6. The method as claimed in anyone of claims 1 to 5, wherein the steam cooked paddy mass is predried to a moisture content of 18 to 20% Wet Basis.
7. A continuous system for processing paddy, the system comprising an automated steam cooker for steam cooking cleaned, presteamed, hot water soaked and water drained paddy mass continuously and uniformly and a predrying arrangement for predrying the steam cooked paddy mass prior to drying thereof.
8. The system as claimed in claim 7, wherein the automated steam cooker comprises a plurality of spaced perforated cooking chambers surrounded by a steam jacket in spaced apart relationship therewith and connected to a water drained paddy inlet through feed inlet passages at the top thereof and connected to a steam cooked paddy discharge outlet at the bottom thereof, each of the perforated cooking chambers being provided with a centrally located perforated steam injector tube, the water drained paddy inlet being provided with a feed rate metering device and the steam cooked paddy discharge outlet being provided with a discharge rate metering device, the steam jacket being provided with a steam inlet, the steam inlet and the steam injector tubes being connected to a steam source through a steam control valve, the feed rate metering device and the discharge rate metering device and the steam control valve being connected to a logic

control automatically to control the water drained paddy feed rate through the water drained paddy inlet and cooked paddy discharge rate through the steam cooked paddy discharge outlet and the steam inflow rate through the steam control valve and maintain a cooking temperature of 95 to 100°C and a pressure of 1000 to 1500 mmwc within the cooking chambers.
9. The system as claimed in claim 8, wherein the logic control is a Programmable Logic Control (PLC).
10. The system as claimed in claim 8 or 9, wherein the steam jacket is provided with an inspection window.
11. The system as claimed in any one of claims 7 to 10, wherein the predrying arrangement comprises a stationary atmospheric air predrying unit and a vibratory hot air predrying unit.
12. The system as claimed in claim II, wherein the stationary atmospheric air predrying unit comprises an atmospheric air predrying chamber having a perforated bottom and a feed hopper at the inlet end thereof and a discharge outlet at the discharge end thereof, the predrying chamber being connected at the top thereof to an air exhaust chimney through atleast one cyclone separator and the bottom of the predrying chamber being connected to a forced atmospheric air blower through air inlet passages provided with air control valves to allow atmospheric air to flow through the air inlet passages and corresponding perforations in the bottom of the predrying chamber in a progressively reducing manner and create progressively reducing air pressure zones from the inlet end

to the discharge end of the predrying chamber to take away the heat and moisture of the steam cooked paddy mass and to move the paddy mass forward and the vibratory hot air predrying unit comprises a hot air predrying chamber provided with a feed hopper at the inlet end thereof, a discharge outlet at the discharge end thereof and an exhaust air outlet, the hot air predrying chamber further comprising a vibratory plenum chamber comprising a channel member extending along the length of the hot air predrying chamber and connected to a forced hot air blower, the channel member being supported on a hollow support structure with the help of springs and adapted to describe a sinusoidal movement in the forward direction, the channel member comprising a plurality of openings along the length of the base thereof and the vibratory plenum chamber further comprising drive means connected to the support structure to impart sinusoidal movement to the plenum chamber.
13. The system as claimed in claim 12, wherein the temperature of the hot air blown by the hot air blower is 100 to 110°C.
14. The system as claimed in claim 12 or 13, wherein the drive means comprises an electric motor having a driver pulley mounted on the shaft thereof, a driven shaft disposed parallel to the motor shaft and rotatably mounted on a pair of spaced apart upright members, a driven pulley mounted on the driven shaft at one end thereof corresponding to the driver pulley on the motor shaft, the driver and driven pulleys being interconnected by a belt, a cam provided on the driven shaft and a cam follower engaged over the cam and connected across the support structure through a cross connector means.

15. The system as claimed in claim 14, wherein the cam is integrally formed on the driven shaft.
16. The system as claimed in claim 14 or 15, wherein the cam follower comprises a first bearing and the cross connector means comprises a crosspin rigidly connected across a bracket which in turn is connected across the support structure and a second bearing mounted on the crosspin and coupled to the first bearing.
17. The system as claimed in any one of claims 12 to 16, wherein the support structure is provided with an access window.
18. The system as claimed in anyone of claims 8 to 18, wherein the feed rate metering device and the discharge rate metering device each is a rotary valve.
19. The system as claimed in any one of claims 8 to 19, wherein the feed inlet passages at the top of the steam cooker diverge towards the cooking chambers and the steam cooker is converging at the bottom thereof.
20. The system as claimed in anyone of claims 7 to 13 wherein the predrying arrangement is for predrying the steam cooked paddy mass to a moisture content of 18 to 20% Wet Basis.
Dated this 31st day of December 2008