WO2021260561A1

WO2021260561A1 - A storage facility for storage of agricultural products

Info

Publication number: WO2021260561A1
Application number: PCT/IB2021/055522
Authority: WO
Inventors: Pravin Chandrakant Phutane; Manoj Chandrakant Phutane; Sanjay Chandrakant Phutane
Original assignee: Pravin Chandrakant Phutane; Manoj Chandrakant Phutane; Sanjay Chandrakant Phutane
Priority date: 2020-06-24
Filing date: 2021-06-23
Publication date: 2021-12-30

Abstract

The present disclosure discloses a storage facility (1000) for storage of agricultural products comprising a plurality of racks (100) having porous sidewalls configured to be mounted on the floor to hold the agricultural products. Each rack includes a plurality of stacks (102) configured in a vertical direction from an operative bottom end (100a) to an operative top end (100b) of the rack (100), a respiratory tubule (104) having porous sidewalls configured in a central portion (100c), an inlet duct (108) and an outlet duct (120) configured on the rack and a plurality of sensors configured to continuously sense air quality inside each of the stacks (102). At least one air conditioning unit (200) is mounted in a corner of the floor and configured to circulate stream of conditioned air through each of the plurality of racks (100), thereby maintaining the agricultural products under controlled climatic conditions.

Description

A STORAGE FACILITY FOR STORAGE OF AGRICULTURAL PRODUCTS

FIELD

The present disclosure relates to storage facilities for agricultural products.

BACKGROUND

The background information herein below relates to the present disclosure but is not necessarily prior art.

Quantitative and qualitative losses of agricultural products occur at post-harvest activities such as handling, transportation, storage, packing and final delivery to a consumer. It becomes important to prevent such losses especially, while storing the agricultural products for a long period of time, since the continuing metabolism of the agricultural produce even after harvesting, results in cellular respiration which causes water loss, rotting and cell softening during storage. As a result, the quality and the value of the product deteriorate thereby causing a huge loss. An example of an agricultural product is the onion, which is a semi-perishable crop. In favorable conditions, onions can be stored for a period of 4-6 months. More specifically, onions need to be stored at a temperature either below5 degrees or above 25 and up to 30 degrees Celsius, and at a humidity level ranging from 60-65%. In a tropical climate, maintaining the temperature of the cold storage facility below 5 degrees is very expensive and at the time of thawing from around 0 degrees upwards, there is a possibility of sprouting, in which case the onion loses its commercial value. Above 30 degrees, the onion bulb starts drying up. Thus, onion is a very sensitive product to temperature and humidity during storage. However, it is difficult to maintain the optimal temperature and humidity conditions in different climatic conditions, as a result of which around 30-40% of the annual produce is typically lost during storage due to physiological weight loss, sprouting, rotting, or rapid growth of fungi.

Conventional storage facilities for agricultural products are enclosed spaces provided with perforated units configured to store the agricultural products therein. Suction fans are provided to ventilate by creating a draught of air in the unit to keep the agricultural produce dry and cool. However, such facilities lack the provisions to maintain the optimal humidity in the facilities. Further, it is difficult to maintain the desired temperature inside the storage facilities. As a result, the quality of the produce is compromised during storage. Additionally, the conventional facilities depend largely on manual inspection methods to check the quality of the products during storage, which is not a feasible solution.

There is therefore, felt a need of a storage facility for storage of agricultural products which alleviates the aforementioned drawbacks.

OBJECTS

Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:

An object of the present disclosure is to provide a storage facility for storage of agricultural products in a space.

Another object of the present disclosure is to provide a storage facility for storage of agricultural products that regulates the temperature and humidity of the space to maintain the quality of the agricultural products.

Yet another object of the present disclosure is to provide a storage facility for storage of agricultural products that ensures uniform ventilation throughout the space for maintaining the quality of the agricultural products.

Still another object of the present disclosure is to provide a storage facility for storage of agricultural products which is cost effective.

Another object of the present disclosure is to provide a storage facility for storage of agricultural products which allows real-time continuous monitoring of the air quality parameters of a storage facility.

Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.

SUMMARY

The present disclosure discloses a storage facility for storage of agricultural products in a space having a floor, a roof, sidewalls and an access door. The storage facility comprises a plurality of racks having porous sidewalls configured to be mounted on the floor to hold the agricultural products. Each of the of rack include a plurality of stacks configured in a vertical direction from an operative bottom end to an operative top end of the rack, a respiratory tubule having porous sidewalls configured in a central portion of the rack extending from the operative bottom end to the operative top end, an inlet duct configured on the operative bottom end of the rack and an outlet duct configured on the operative top end of the rack, a plurality of sensors configured in each of the stacks to continuously sense air quality inside each of the stacks. Atleast one air conditioning unit is to be mounted in the space and configured to be in fluid communication with the inlet duct and the outlet duct. Each of the air conditioning units are configured to be in communication with the sensors and to circulate stream of conditioned air through each of the plurality of racks, thereby maintaining the agricultural products under controlled climatic conditions.

In a preferred embodiment, in a first configuration the stream of conditioned air is configured to enter each of the rack in a radial direction and exit each of the racks in an axial direction, and in a second configuration the stream of conditioned air is configured to enter each of the racks in an axial direction and exit each of the racks in a radial direction.

In a preferred embodiment, a stack sheet is disposed between adjacent stacks. The stack sheet is made in such a way that it allows only 5 to 10 percent of the air to diffuse to adjacent stacks while 90 to 95 percent of the air flows out directly without mixing with adjacent stacks.

In a preferred embodiment, the shape of the rack formed by the sidewalls form a regularly shaped structure such as rectangle, circle.

In yet another embodiment, the shape of the rack by the sidewalls form an irregularly shaped structure such as a variably dimensioned structure.

In a preferred embodiment, a plurality of gyrate rings is disposed at predetermined locations along the extent of the respiratory tubule from the operative bottom end to the operative top end of the rack.

In still another embodiment, the dimensions of the respiratory tubule vary along the extent of the respiratory tubule from the operative bottom end to the operative top end of the rack.

In a preferred embodiment, the outlet duct near of each of the racks are connected together to a common duct. In a preferred embodiment, wherein the air conditioning unit includes a heating unit, a cooling unit, a humidifier, a temperature sensor, an air flow sensor, conditioned air temperature sensor, a flow control device and a suction fan.

In a preferred embodiment, the sensors are configured to sense air quality parameters from the group consisting of temperature, humidity, carbon dioxide concentration, oxygen concentration, nitrogen concentration, ammonia concentration, ethylene concentration.

In a preferred embodiment, a display unit (not shown in figures) is provided in the space configured to be electronic communication with said sensors and provide status of information of each rack.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWING

A storage facility for storage of agricultural products, of the present disclosure will now be described with the help of the accompanying drawing, in which:

Figure 1 illustrates a top view of the storage facility for storage of agricultural products, in accordance with first embodiment of the present disclosure;

Figure 2 illustrates a side view of the Figure 1 ;

Figure 3 illustrates a side view of the Rack of Figure 1 ;

Figure 4 illustrates a top view of Figure 3;

Figure 5 illustrates a side view of the Rack of Figure 1, in accordance with second embodiment of the present disclosure;

Figure 6 illustrates a top view of Figure 5;

Figure 7 and Figure 8 illustrate an air flow path through the rack of Figure 2;

Figure 9 illustrates front view of the air conditioning unit of Figure 1 ;

Figure 10 illustrates a side view of the HVAC unit of Figure 9;

Figure 11 and Figure 12 illustrate air flow around the rack of Figure 3;

Figure 13-16 - illustrate various embodiments of the respiratory tubule; Figure 17 shows an isometric view of a gyrate ring located in the respiratory tubule;

Figure 18 shows a top view of the gyrate ring of the Figure 17;

Figure 19 shows the top view of the stack sheet;

Figure 20 shows a chart illustrating daily temperature and humidity inside the space; Figure 21 shows a chart illustrating analysis of storage losses inside the space;

Figure 22 shows a chart illustrating analysis of storage losses during various development stages of storage facility;

Figure 23 shows a chart illustrating root cause analysis of storage losses inside the space of the storage facility; and Figure 24 shows a chart illustrating comparative storage losses analysis of present disclosure versus conventional naturally ventilated storage spaces.

LIST OF REFERENCE NUMERALS USED IN DETAILED DESCRIPTION AND DRAWING

1000 - storage facility 100 -rack

100a - bottom end

110b - top end

100c - central portion

102 - stack 104 - respiratory tubule

105 - gyrate ring

106 - flow control mechanism

108 - inlet duct

110 - loading hatch 112 - unloading door

114 -laminar air flow 116 - stack sheet 118 - air flow control valve 120 - outlet duct

200 - air conditioning unit

201 - flow control device

202 - suction fan 204 - humidifier 206 - heating unit

208 - cooling unit 210 - flow control device 212 - temperature sensor 214 - humidity sensor 216 - air flow sensor

218 - conditioned air temperature sensor 300 - grading and sorting facility 310 - conveyors A - axial direction R - radial direction

DETAILED DESCRIPTION

Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing. Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.

The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, elements, components, and/or groups thereof.

A preferred embodiment of a storage facility for storage of agricultural products in a space, of the present disclosure will now be described with reference to Figure 1 through Figure 24. The preferred embodiment does not limit the scope or ambit of the present disclosure.

The storage facility for storage of agricultural products in a space (hereinafter referred to as ‘the storage facility 1000’) is configured to be climate controlled thereby maximizing the storage life of the agricultural product.

The storage facility 1000 includes a space having a floor, a roof, sidewalls having insulation and an access door. The floor of the space is provided with at least one raised platform aligned along the dimensions of the space. The storage facility 1000 comprises at least one rack 100 having stacks 102 arranged in a vertical direction from an operative bottom end 100a to an operative top end 100b. The rack 100 is a multi-level storage structure made up of structure steel like pipe, square tube duly powder-coated or painted. The rack 100 is configured to be mounted on the floor to hold agricultural products. An air conditioning unit 200 is provided in the space. The air conditioning unit 200 is configured to be in fluid communication with each of the stacks 102 to facilitate supplying stream of conditioned air to the rack 100 and receive discharged air by the rack 100. The rack 100 is located on the platform. The rack 100 has a pervious bottom surface, an impervious top surface, and perforated outer sidewalls. The outer sidewalls are made of perforated sheet which helps in retaining the agricultural products to be stored while allowing the air to pass laterally. The rack 100 extends from an operative bottom end 100a resting on the platform to an operative top end 100b. The rack 100 has an operative central portion 100c. Each rack 100 includes a loading hatch 110 and an unloading door 112. The loading hatch 110 is configured to load the products into the rack 100, and the unloading door 112 is configured to unload the products from the rack 100.

Each of the racks 100 is divided into multiple compartments with the help of separating floors. Each separate compartment in the rack 100 is called the stack 102. The rack 100 is divided into a plurality of stacks 102 with the help of stack sheets 116. In an embodiment, the rack 100 is divided into four stacks 102. The stack floor is made up of structural tube capable of taking load of agricultural products stored in each stack 102. The floor of stacks 102 is supported by powder coated steel sheets. The stack sheets 116 have holes arranged in specific manner as shown in figure 19 with diameter of 20mm and pitch of 100mm. The stack holes allow passage of air to the bottom layer of the agricultural products. This allows gaseous exchange and aeration required by the bottom most layer on the agricultural product. The stack sheets 116 are pervious to facilitate efficient ventilation of a stack 102 from an adjacent stack 102. In an embodiment, each stack 102 is configured with a height of at least 1 meter, to avoid pressure of top products damaging products located on bottom layers. The stack sheet 116 is made in such a way that it allows only 5 to 10 percent of the air to diffuse to adjacent stacks 102 while 90 to 95 percent of the air flows out directly without mixing with adjacent stack 102.

In an embodiment, the rack 100 is of any geometrical shape which allows storage of agricultural products therein. In another embodiment, the rack 100 is of circular or square shape (as shown in Figures 3, 4, 5 and 6).

Each of the racks 100 further comprises a hollow tubule made up of sheet material with painting having multiple holes arranged in specific manner to allow uniform and 360 degree flow of air. This tubule is called the respiratory tubule 104. The respiratory tubule 104 has porous sidewalls and is configured in the central portion 100c of the rack 100. The respiratory tubule 104 extends from the operative bottom end 100a to the operative top end 100b of the rack 100. At the operative bottom end 100a of the tubule 104, a flow control mechanism 106 is provided to facilitate regulation of flow of the conditioned air through the rack 100, so that the conditioned air mingles with the agricultural products in an efficient manner. The flow control mechanism 106 includes flow control valves 118 to regulate the air flow through each stack 102. The air flow control valves 118 are further configured to shut off the air flow when a particular rack 100 is empty.

In an embodiment as shown in figure 13 the diameter of pores on the sidewalls of the respiratory tubule 104 is 2 mm.

In another embodiment as shown in figure 14 the diameter of pores on the sidewalls of the respiratory tubule 104 is 5 mm.

In yet another embodiment, the respiratory tubule 104 is further provided with a plurality of gyrate rings 105 as shown in figure 15 disposed at predetermined locations along the extent of the respiratory tubule 104 from said operative bottom end 100a to the operative top end 100b of the rack 100. The gyrate rings 105 facilitate creation of a swirling effect inside the respiratory tubule 104. The gyrate rings 105 are made of powder coated steel material. The gyrate ring 105 is provided with 6 fins with each fin configured to be bent at an angle of 30 degrees along the width of the gyrate ring 105 to facilitate efficient aerodynamic characteristics. This allows smooth gliding of air in respiratory tubule and creates a swirling effect in the respiratory tube 104. The gyrate rings 105 are fitted at each stack level.

In an embodiment, the shape, the quantity and the sizes of holes of the respiratory tubule 104 is adjustable, which allows uniform distribution of air in all lateral directions.

In still another embodiment as shown in the figure 16, the respiratory tubule 104 has a variable cross section extending from the operative bottom end 100a to the operative top end 100b.

Each rack 100 further comprises an inlet duct 108 configured on the operative bottom end 100a of the rack 100. The inlet duct 108 is configured to provide the conditioned air to the rack 100 through the respiratory tubule 104 into each stack 102 to facilitate ventilation of the agricultural product stored in the stack 102. A flanged connection having gasket in between the respiratory tubule 104 and the inlet duct 108 is provided which prevents leakage of air. Each rack 100 further comprises an outlet duct 120 configured on the operative top end 100b of the rack 100 to collect the air permeated through the side walls of the stacks 102 and the pores of the respiratory tubule 104. The outlet duct 120 is configured to be connected to the air conditioning unit 200 to facilitate recirculating of the air exiting the rack 100 through the air conditioning unit 200. The outlet duct 120 includes a plurality of diffuser ports (not shown in any figures) positioned on the sidewalls of the space. The diffuser ports are configured to collect discharged air by the racks 100 to the air conditioning unit 200 as and when required.

In an embodiment, each of the racks 100 is configured with a plurality of outlet ducts 120 as shown in the figure 7 and figure 8.

In an embodiment, the outlet duct 120 is configured to collect the air from a single diffuser located at the center point of the rack 100 on the operative top end 100b as shown in Figures 11 and 12.

Each rack 100 further comprises a plurality of sensors configured to be mounted in each of the stacks 102 to continuously sense the air quality parameters inside each of the stacks 102.

In an embodiment, the shape of the racks 100 formed by the sidewalls form a regularly shaped structure such as rectangle, circle.

In another embodiment, the shape of the stacks 100 formed by the sidewalls form an irregularly shaped structure, such as a variably dimensioned structure.

The air conditioning unit 200 is a vertical Heating Ventilation and Air Conditioning Unit configured to facilitate maintaining of the air quality inside each of the stacks 102 at desired levels. The air quality parameters include from the group consisting of temperature, humidity, carbon dioxide concentration, oxygen concentration, nitrogen concentration, ammonia concentration, ethylene concentration as required by the agricultural product to be stored. The air conditioning unit 200 includes an inlet manifold, a cooling unit 208, a heating unit 206, a humidifier 204 and a suction fan 202. The inlet manifold is configured to receive the air flowing through the chamber. The cooling unit 208 and the heating unit 206, each have an inlet valve configured to draw in the air from the inlet manifold depending on the temperature of the received air. The operation of the inlet valves is controlled by a flow control device 201 provided adjacent to the inlet manifold. In one embodiment, the degree of opening of the valves is automatically controlled. In another embodiment, the degree of opening of the valves is manually controlled.

In an embodiment, the air conditioning unit 200 includes a temperature sensor 212 and a microprocessor for facilitating automatic controlling of the degree of opening of the valves. The temperature sensor 212 is configured to sense the temperature of the air received in the manifold, and is further configured to generate a sensed temperature value corresponding to the temperature of the air. The microprocessor is configured to receive the sensed value and open the valve of either the cooling unit 208 or the heating unit 206. In an embodiment, the microprocessor includes a memory and a comparator. The memory is configured to store a threshold temperature value. The comparator is configured to receive the sensed value from a first sensor, and is further configured to compare the received value with the threshold temperature value. The comparator either generates a first actuating signal to open the cooling unit 208 or a second actuating signal for opening the heating unit 206. More specifically, if the sensed value is more than the threshold value, the comparator generates a first actuating signal to adjust the degree of opening of the inlet valve of the cooling unit 208, and allow the air flow into the cooling unit 208 to facilitate cooling of the air passing there through. If the sensed value is less than the threshold value, the comparator generates a second actuating signal to adjust the degree of opening of the inlet valve of the heating unit 206, and allow the air flow into the heating unit 206 to facilitate heating of the air passing there through.

In an embodiment, the air conditioning unit 200 further includes a humidity sensor 214 configured to sense the humidity of the air received from the rack 100, and generate a sensed humidity value. The memory is configured to store a threshold humidity value. If the humidity in the air is more than the threshold value, the comparator is configured to compare the sensed humidity value with the threshold humidity value to generate a first compared humidity signal for actuating the heating unit 206. Actuating the heating unit 206 facilitates increase in the temperature of the air to enable condensation of the moisture, thereafter which the condensate is removed from the air. Thereafter, the cooling unit 208 is actuated with the help of temperature sensor 212 which senses the increase in temperature to enable decrease in temperature of the storage facility 1000. Thus, the air conditioning unit 200 helps in maintaining the temperature and humidity levels at desired values. In another embodiment, if the humidity of the air is less than the threshold value, the comparator generates a second compared humidity signal for actuating the humidifying unit. The humidifier includes a mist pump connected to a water tank. Upon receiving the second humidity signal from the comparator, the mist pump is configured to spray water into the air passing there through.

The air conditioning unit 200, thus conditions the air to maintain the air quality parameters at desired levels. In the first configuration, the conditioned air is configured to enter the rack 100 in the axial direction A and exit the rack 100 in the radial direction R, as shown in the figure 3. In a second configuration, the conditioned air is configured to enter the rack 100 in the radial direction R and exit the rack 100 in the axial direction A, as shown in the figure 11. The suction fans 202 are configured to push the conditioned air out of the unit and facilitate conditioning of the storage facility 1000. In an embodiment, the suction fans 202 are configured to induce a laminar air flow 114 through the inlet duct 108. Thus, the conditioned air stream enters the rack 100 in the axial direction A and exits the rack 100 in the radial direction R. The conditioned air is circulated at a velocity of 2m/s ± 0.5 to ensure sufficient ventilation through the stacks 102. In another embodiment, the air conditioning unit 200 creates a suction pressure difference at the outlet duct 120 which produces a laminar air flow.

In an embodiment, the suction fans 202 are configured to rotate in a reverse direction to facilitate sucking in of the air by the suction fans 202. Reversing the direction of air flow causes the air to be sucked in the opposite direction by the air conditioning unit 200. Thus, the reversal of the flow of conditioned air enters the rack 100 in the radial direction R and exits the rack 100 in the axial direction. During reverse directional flow of the air, the microprocessor switches off the cooling unit 208, the heating unit 206 and the humidifier 204. In one embodiment, the reverse direction of air flow is preferable for certain sensitive products, rather than direct airflow.

In an embodiment, the cooling unit 208 includes an evaporator coil. In another embodiment, the suction fans 202 are provided with variable flow drive to control the amount of air passing through the air conditioning unit 200.

In one embodiment, the air conditioning unit 200 includes an air flow sensor 216 configured to sense the air flow rate while the air passes to the suction fans 202 through the humidifier 204, and a conditioned air temperature sensor 218 provided near the suction fans 202 and configured to sense the temperature of the conditioned air.

In another embodiment, if the concentration of C(¾ and ethylene is more than a threshold value, the diffuser ports provided on the wall of the space are configured to release the C(¾ and ethylene into the environment. In another embodiment, if the concentration of ammonia in the air mingled with the agricultural products in a stack 102 is more than the desired amount, the sensors generate an ammonia sensing signal which is received by the remote control unit. The remote control unit generates an alarm signaling for removing of the agricultural products from the stack 102 by means of telescopic conveyors. In one embodiment, the micro-processor is communicatively coupled to a remote control unit with the help of wireless communication module. In an embodiment, the wireless communication module includes an IOT based communication module. The wireless communication module enables on-site monitoring of the temperature, humidity and gas analysis of the air passing through the agricultural products to ensure maximum storage life of the products. In another embodiment, the wireless communication module is configured to facilitate remote monitoring on a plurality of remote control units.

In a preferred embodiment, a display unit (not shown in figures) is provided in the space configured to be electronic communication with said sensors and provide status of information of each stack 102.

In one embodiment, the storage facility 1000 includes a pre-storage unit and a post-storage unit. The pre-storage unit is a processing chamber configured to facilitate grading and sorting of the agricultural products typically, by visual inspection at a grading and sorting unit 300. In an embodiment, the grading is done with the help of meshed conveyors. Sorting of the products is required for segregating dry and moist products from each other. In an embodiment, the storage facility 1000 includes a curing chamber complete with a plurality of racks, discharge duct and an air conditioning unit 200, and configured to allow curing of the moist product by maintaining temperature and humidity above the optimal levels. The graded and sorted agricultural products are conveyed to different stacks 102 with the help of conveyors 310, based on the average size of the product.

The post-storage unit includes a telescopic loader and conveyor connected to a packing unit for packing the agricultural product before being delivered to a consumer. The storage facility 1000 of the present disclosure, is configured to store agricultural products irrespective of the sensitive nature thereof. More specifically, the storage facility 1000 stores the agricultural products throughout the year without causing any damage to the product, and thereby to the commercial value of the product.

In one aspect, the present disclosure envisages a method for safely storing agricultural products in the storage facility 1000. The method includes the following steps:

• conducting a visual quality inspection of incoming agricultural products to sort the products into moist, dry and rejection categories;

• conveying the dry products to a processing chamber;

• curing the moist products to obtain a dry category of the products;

• conveying the cured products to the processing chamber;

• grading the sorted products in different types depending on the size and quality of the agricultural products, in the processing chamber;

• conveying and placing the sorted and graded products to individual stacks 102 of racks 100 provided in the storage facility 1000;

• pre-conditioning the storage facility 1000 for a pre-determined time period to bring the temperature to a desired temperature range and the humidity to a desired humidity range for acclimatizing the agricultural products to optimal storage conditions;

• providing air conditioned at optimal temperature and humidity ranges, through the storage facility 1000 to ensure proper air passage through the racks 100 for proper exposure of the products to the conditioned air;

• monitoring the temperature and humidity levels, and concentration of C(¾, (¾_, ethylene and ammonia in each rack 100;

• if the concentration of C02 and ethylene in the air increases beyond a threshold value either C02 exhaust diffusers are opened to exhaust the air or air is circulated through C02 scrubber and thereby C02 concentration is maintained. • The concentration of 02 is maintained inside the chamber by injecting Nitrogen gas

• conducting a visual inspection of the agricultural products in the stack 102, if the concentration of ammonia increases beyond a threshold value to discard the products if rotten; and

• conveying the products to a packing unit as per the requirements.

In a working embodiment, the storage facility 1000 is configured to store onions therein for a period of six to eight months. As onions are semi-perishable agricultural products, storing the onions under controlled temperature and humidity conditions is essential for maintaining its maximum storage life and value. Once the onions are received at the storage facility 1000, a visual inspection of the onions is performed wherein the onions are classified into moist, semi-moist and dry categories depending on the external skin texture of the onion. The dry products are conveyed to a processing chamber, whereas the semi-moist and the moist onions are conveyed to a curing unit for a predetermined time period. The curing unit includes a plurality of racks configured to receive the semi-moist or moist onions. More specifically, moist onions are cured at a temperature of 30 to 40 degrees Celsius for a period of 6-7 days depending upon the variety & condition of onion bulbs. The ventilation fluid flow rate is maintained through the stacks 102 at 55-60 passes/hr. The cured onions are then conveyed to the processing chamber wherein the onions are graded according to their size with the help of a grading unit. In an embodiment, the onions are graded in five different mesh grading machines. The graded onions are then conveyed to the rack 100 and are placed in stacks 102. Grading allows onions of the same size to be placed in the same stack 102. In order to acclimati e the onions to optimal air conditions inside the chamber, the onions are subjected to air conditioned at a pre-determined temperature varying in the range of 25 to 30 degree Celsius and the relative humidity varying in the range of 60 to 65% for a desired time period of 72 hours. Thereafter, the optimal conditions are maintained throughout the storage life. In an embodiment, the suction fans 202 are rotated in a centrifugal direction to allow the conditioned air to pass through the inlet duct 108 into the respiratory tubule 104, and into the stacks 102. Periodically, the flow of the air is reversed by changing the direction of rotation of the suction fans 202 to centripetal direction. As a result, the air is sucked in by the HVAC unit 200. While the air rushed back into the inlet duct 108, the sensors sense the temperature and humidity, and concentration of C(¾, (¾_, ethylene and ammonia levels to control the C(¾_, O2 and ethylene. If the sensed concentration of ammonia is more than the threshold value, the onions are removed from the stack 102.

Figures 20-24 show observations recorded while performing health analysis of onion as an agricultural product. It is observed that with the storage facility 1000 of the present disclosure with varying capacities i.e. 2 metric ton, 20 metric ton, and 200 metric ton the losses were significantly eliminated as compared to a conventional naturally ventilated environment.

The 2 metric ton storage facility had the following configuration-

Pressurized Air at the bottom Chamber

Air Flow through Product

Air Direction - Bottom to Top

Single Stack - Material kept in stock on top of each other

The 20 metric ton storage facility had the following configuration-

Pressurized Air at the bottom Chamber

Free Flow through Product

Suction at Top

Ducted System

Air Flow - Bottom to Top

Multiple Stack - Material kept in Crates on top of each other

The 200 metric ton storage facility had the following configuration-

Pressurized Air coming from inlet duct to respiratory tubule.

From the respiratory tubule flows laterally and centrifugally over product.

Air Sucked by outlet duct placed above the rack and carried to air conditioning unit.

Air Flow Control & Monitoring mechanism added Various Gaseous analysis system added

• Multiple racks with multiple stacks in one space

• Pre determined Laminar Air Distribution System - Air flow from bottom to top and then lateral centrifugal over the Products

• Material kept loose in stack.

The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.

TECHNICAL ADVANCES AND ECONOMICAL SIGNIFICANCE

The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a storage facility for agricultural products in need of storage that:

• efficiently regulates the temperature and humidity of the facility to maintain the quality of the agricultural products;

• ensures uniform ventilation throughout the facility for maintaining the quality of the agricultural products;

• is cost effective; and

• allows real-time monitoring of the storage facility for continuously regulating the working parameters.

The foregoing description of the specific embodiments so fully reveals the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, step, or group of elements, steps, but not the exclusion of any other element, step, or group of elements, or steps. While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.

Claims

CLAIMS:

1. A storage facility (1000) for storage of agricultural products in a space defined by a floor, a roof, sidewalls and an access door for creating a climate-controlled environment, said storage facility (1000) comprising:

• at least one rack (100) of stacks (102) arranged in a vertical direction from an operative bottom end (100a) to an operative top end (100b) of said rack (100); said rack (100) having porous sidewalls and configured to be mounted on the floor to hold said agricultural products; each of said plurality of racks (100) including: o a respiratory tubule (104) having porous sidewalls configured in a central portion (100c) of said rack (100) extending from said operative bottom end (100a) to said operative top end (100b); o at least one inlet duct (108) and at least one outlet duct (120) configured to be in fluid communication with said stack (102); o a plurality of sensors (not shown in figures) configured in each of said racks (100) to continuously sense air quality inside each of said racks (100);

• at least one air conditioning unit (200) provided in said space and configured to provide conditioned air to each of said inlet ducts (108) and to receive expelled air from each of said outlet ducts (120), and further configured to receive signals form said sensors, and thereby maintain the temperature and humidity within the environment in each rack (100).

2. The storage facility (1000) as claimed in claim 1, wherein a display unit (not shown in figures) is provided in said space, said display unit configured to be electronic communication with said sensors and provide status of information of each stack (102).

3. The storage facility (1000) as claimed in claim 1, wherein in a first configuration said stream of conditioned air is configured to enter each of said racks (100) in a radial direction (R) and exit each of said racks (100) in an axial direction (A), and in a second configuration said stream of conditioned air is configured to enter each of said racks (100) in an axial direction (R) and exit each of said racks (100) in an radial direction (A).

4. The storage facility (1000) as claimed in claim 1, wherein a stack sheet (116) is disposed between adjacent stacks (102) to prevent mixing of air in between the adjacent stacks (102), said stack sheet (116) being made of a pervious material.

5. The storage facility (1000) as claimed in claim 1, wherein the shape of said rack (100) formed by the sidewalls form a regularly shaped structure such as rectangle, circle.

6. The storage facility (1000) as claimed in claim 1, wherein said rack (100) has irregularly shaped sidewalls.

7. The storage facility (1000) as claimed in claim 1, wherein a plurality of gyrate rings (105) are disposed at predetermined locations along the extent of said respiratory tubule (104) from said operative bottom end (100a) to said operative top end (100b) of said rack (100).

8. The storage facility (1000) as claimed in claim 1, wherein the dimensions of said respiratory tubule vary along the extent of said respiratory tubule from said operative bottom end (100a) to said operative top end (100b) of said rack (100).

9. The storage facility (1000) as claimed in claim 1, wherein said outlet duct (120) near each of said racks (100) are connected together to a common duct (not shown in figures).

10. The storage facility (1000) as claimed in claim 1, wherein said air conditioning unit (200) includes a heating unit (206), a cooling unit (208), a humidifier (204), a temperature sensor (212), an air flow sensor (216), conditioned air temperature sensor (218), a flow control device (201) and a suction fan (202).

11. The storage facility (1000) as claimed in claim 1, wherein said sensors are configured to sense air quality parameters selected from the group consisting of temperature, humidity, carbon dioxide concentration, oxygen concentration, nitrogen concentration, ammonia concentration, and ethylene concentration.