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(11) | EP 3 147 588 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | A METHOD FOR COOLING FERTILIZERS AND A SYSTEM FOR COOLING FERTLIZER |
| (57) A method for cooling fertilizer, according to the invention, in cooler outside air
at atmospheric pressure whose flow is induced fan, characterized in that the outside
air prior to delivery to the cooler (1) is compressed in at least one compressor (3)
to a pressure of between 4 to 15 bar are discharged from any excess water and dried,
and then expanded to approximately atmospheric pressure. A system for cooling fertilizer, according to the invention, containing a fertilizer cooler, fan, characterized in that the has at least one compressor (3), compressing air to a pressure in the range of 4 to 15 bar, connected to a wet tank (4) which is connected to the air dehumidifier (5), which are connected via the expansion device (6) of the fertilizer cooler (1) before the inlet of outside air to the cooler (1). |
[0001] Invention provides a cooling method of fertilizers and cooling system for cooling of fertilizers. Solution of the invention is carried out with the use of cooling ambient air in a cooler, eg. a drum cooler (using open gaseous refrigerant circuit with atmospheric air as a refrigerant).
[0002] It is commonly used a cooling fertilizers in a drum cooler outside air at atmospheric pressure, which the air circulation is forces by fan. So far, during the summer (high temp. outside air) was connected additional refrigeration equipment (chiller) with the cooler cooling outside air supplied to the fertilizer cooler. In the description of the invention CN104406377 the device is known for cooling fertilizer containing a fertilizer drum cooler connected with the fan.
[0003] General technological recommendations for production of fertilizers specify that at the input of the cooler outside air cooling fertilizer should have a relative humidity of ϕ <50%. Detailed guidelines pay attention to not exceed the critical values of relative humidity CRH for the type of fertilizer as there is an increased possibility of moisture absorption and caking. When storing fertilizer under ϕ> 50% above 8h - should be used for dehumidification. Production and storage buildings should be closed tightly and kept inside ϕ = 40-50%.
[0004] A method for cooling of fertilizers in the cooler according to the invention, consisting in cooling the fertilizers outside air at atmospheric pressure whose flow is induced fan, characterized in that the outside air prior to delivery to the cooler is compressed in at least one compressor to a pressure of between 4 to 15 bar. Is discharged from outside air any excess water and dried, for example in the membrane cooler outside air or sprayed water cooler (adiabatic cooling) or by the refrigeration apparatus, then the air is expanded to a pressure close to or equal to atmospheric pressure and cooled at the same time and then directed to the cooler.
Preferably, the outside air prior to the compressor is compressed further in the initial compressor taking advantage of the work of expansion to the pre-compression air. When the temperature of fertilizer at the outlet of the cooler is too high (higher than required) and the outdoor air has a temperature less than fertilizer after leaving the cooler, intensifies the outside air flow by the auxiliary fan.
[0005] A system for cooling fertilizers according to the invention comprising a fertilizer cooler, fan, characterized in that it contains at least one compressor for the compression of air to a pressure in the range of 4 to 15 bar, connected to at least one wet tank (which separates the excess water) which is connected to the air dryer (air dehumidification and / or cooling the compressed air and can be located behind or inside the wet tank). These elements are connected via at least one expansion device to the inlet of to the fertilizer cooler. The inlet to the cooler can be connected to the external supply air duct to the cooler. In the system there may be other elements used in the compressed air as filters, droplet separators, the reservoir of dry air etc..
Preferably, the system has an auxiliary fan from air intake to the cooler. Auxiliary fan intensifies the air flow and is switched on for example when the temperature of the fertilizer at the outlet of the cooler is too high (higher than required) and the outdoor air has a temperature less than fertilizer after leaving the cooler.
Preferably the system before the expansion device is connected with the compressed air, for example fitted to an industrial plant in which the solution according to the invention is applied. This installation can be connected front of the expansion device to support the work of the proposed cooling system (fertilizer or as other loose material) or a first degree of compression. This system, if it contains at least a compressor, a wet tank and a dehumidifier, and produces a suitable amount of the dried air at a pressure of 4-15 bar can replace the compressor, dryer and wet tank in proposed arrangement.
Preferably, the system has pre-compressor (the first stage of compression) connected to the expansion device, which is connected to at least one compressor (the second stage of compression). Pre-compressor is connected to a compressed air reservoir which is connected to at least one compressor. This allows for the storage air in the compressed air tank, and then use it later to optimize the system operation.
Preferably the system has a cooling system controller, which is connected to temperature sensors and / or humidity of outside air: of the inlet of the cooler and / or out of the system. The controller may also be connected with a temperature sensor of the fertilizer at the outlet of the cooler and / or a temperature sensor and humidity expanded at the inlet of the cooler. The controller may also be connected to the expansion device and / or dehumidifier and at least one compressor. The controller based on the measured temperature and humidity activates the compressors, the initial compressor, dryer, auxiliary fan, opens the expansion device, the reservoir of compressed air. The controller can be connected to all or selected elements of the system.
Preferably, the system with the pre-compressor has a controller cooling system, which is connected to temperature sensors and / or humidity of outside air: of the inlet of the cooler and / or out of the system. A controller may also be connected to a temperature sensor fertilizer at the outlet of the cooler and / or a temperature sensor and / or humidity expanded air at the inlet of the cooler and to the expansion device, pre-compressor and / or compressed air reservoir and / or dryer, and at least one compressor. The controller can be connected to all or selected elements of the system.
Expansion device comprises at least one nozzle and / or the expansion valve or at least one expander.
[0006] The advantages of the present invention is the ability to connect to an existing compressed air system at the production plant to increase the capacity reserves of compressed air in periods without the cooling demand, the possibility of air accumulation during the night and expansion with peaks load (moderate power consumption), use expansion air to drive the pre-compressor, cooled expanded air is mixed with the outside air flowing to the fertilizer cooler in a proportion of from 10 to 50%.
[0007] Invention is more closely illustrated in the following embodiments and the drawing, in which Fig. 1 shows a system according to the invention, Fig. 2 shows the system of Fig. 1 with the controller and the compressed air installation, Fig. 3 shows a system of the pre-compressor and a compressed air tank 7.
EXAMPLE I
[0008] A system for cooling fertilizer contains the fertilizer drum cooler 1 and the fan 2 It has three compressors 3 connected to a wet tank 4, which is connected to the air dryer 5, which are connected via the expansion device 6 with a fertilizer drum cooler 1 at the inlet of outside air to the cooler 1 .
Outside air is pumped via a fertilizer drum cooler 1 by the fan 2. Compressors 3 compress the air to a pressure of 4 bar and pressing them into the wet tank 4 wherein excess water is isolated. The compressed air is dried in the dryer 5. After drying, the air is expanded in the expansion device (expansion valve) 6 and directed to the inlet of the cooler 1, where it mixed with the outside air.
EXAMPLE II
[0009] The system and method carried out analogously to Example I, with the expanded and outside air mixed on the outside air inlet to the cooler 1, the expansion device 6 has the form of a nozzle. One compressor 3 compresses the air to a pressure of 15 bar. The system is equipped with an auxiliary fan 7 placed on the cooler 1 in place to draw outside air to the cooler 1. Fan 7 intensifies the flow of the outside air, additionally using a fan air can be heated or cooled.
EXAMPLE III
[0010] The system and method carried out analogously to Example II, wherein the set of compressors 3 compresses the air to a pressure of 7 bar. Before the expansion device 6 is connected to the system a compressed air installation 8, which supports the operation of compressors 3.
EXAMPLE IV
[0011] The system and method carried out analogously to Example II or III, wherein the system has a controller 9 of the cooling system, which is connected with temperature and humidity sensor outdoor air of the inlet to the cooler 1 and the outside of the system, a temperature sensor of fertilizer at the outlet of the cooler 1, a temperature and humidity sensor expanded air of the inlet to the cooler 1, the expansion device 6 and the set of compressors 3.When the temperature of the fertilizer at the outlet of the cooler 1 is higher than required, and the outdoor temperature below the temperature of the fertilizer behind the cooler 1 then the controller 9 activates the auxiliary fan 7 in order to enhance the flow of air passing through the cooler 1. The controller 9 also activates the compressor 3, and opens the expansion device 6 allowing the flow of compressed / decompressed air. The controller 9 can control the cooling system of the expanded air, so as not to exceed the critical value of the relative humidity of the inlet to the cooler 1.
EXAMPLE V
[0012] The system and method carried out analogously to Example IV, wherein the system behind the expansion device 6 is connected to the pre-compressor 10 by the shaft (or pre-compressor and expander are in one device), which is connected with a tank 11 for compressed air. The tank 11 is connected to the compressor unit 3. Thanks to the expansion work the outside air is compressed in compressor 10 and directed to the tank 11 for the compressed air.
EXAMPLE VI
[0013] The system and method carried out analogously to Example V wherein the system is not connected to the compressed air system 8 and the auxiliary fan 7.
EXAMPLE VII
1. A method for cooling fertilizer in cooler outside air at atmospheric pressure whose
flow is induced fan, characterized in that the outside air prior to delivery to the cooler (1) is compressed in at least one
compressor (3) to a pressure of between 4 to 15 bar are discharged from any excess
water and dried, and then expanded to approximately atmospheric pressure.
2. A method according to claim 1, characterized in that the outside air prior to delivery to the compressor (3) is compressed additionally
in the initial compressor (10).
3. A method according to claim 1, characterized in that the outside air flow is intensifies by the auxiliary fan (7).
4. A method according to claim 1, characterized in that the expanded air before entering the inlet of the cooler is mixed with the outside
air.
5. A system for cooling fertilizer containing a fertilizer cooler, fan, characterized in that the has at least one compressor (3), compressing air to a pressure in the range of
4 to 15 bar, connected to a wet tank (4) which is connected to the air dehumidifier
(5), which are connected via the expansion device (6) of the fertilizer cooler (1)
before the inlet of outside air to the cooler (1).
6. The system according to claim 5, characterized in that it has an auxiliary fan (7) before the inlet of outside air to the cooler (1).
7. The system of claim 5 or 6, characterized in that before the expansion device (6) is connected to a compressed air system (8).
8. The system according to claim. 5 or 6 or 7, characterized in that a pre-compressor (10) connected to the expansion device (6) and with at least one
compressor (3) or with the tank of compressed air (11) which is connected to at least
one compressor (3).
9. The system according to claim. 5 or 6 or 7, characterized in that has a controller (9) of the cooling system, which is connected with temperature and/or
external humidity sensors of the inlet to the cooler (1) and/or external to the system
and / or temperature sensor fertilizer at the outlet of the cooler (1) and / or a
temperature and/or humidity sensor expanded air at the inlet of the cooler (1) and
/ or the expansion device (6) and / or a dehumidifier (5) and at least one compressor
(3).
10. The system according to claim. 8, characterized in that has a controller (9) of the cooling system, which is connected to temperature sensors
and / or humidity sensor of outside air at the inlet to the cooler (1) and / or external
to the system and / or temperature sensor of fertilizer at the outlet of the cooler
(1) and / or a temperature sensor and / or expanded air humidity sensor at the inlet
of to the cooler (1) and with a expansion device (6), pre compressor (10) and / or
a tank of compressed air (11) and / or dehumidifier (5) and at least one compressor
(3).
11. The system according to claim. 5, characterized in that the expansion device (6) is in form at least one nozzle and / or the expansion valve
or at least one expander.
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.
Patent documents cited in the description