Roasting system for plant-based bulk materials and method of operating the roasting system

Abstract

The present invention relates to a roasting system for a plant bulk material (16) having a housing configuration (4), the housing configuration (4) comprising at least one roasting device (6) having an internal space (10) in which the bulk material (16) can be roasted, a heating system (8;9) enabling heat transport to the bulk material (16) within the internal space (10) using a heating fluid, a solids separator for purifying exhaust from the roasting device (6), and a control system (20) for controlling the roasting process, wherein the heating system (8;9) comprises electric heating elements (22;23) and gas combustion devices (24;25), each connected to the control system (20) for control purposes to achieve different heating modes and different heating outputs. Furthermore, the present invention relates to a method for operating such a roasting system (6).

Description

[[Technical Field]]

[0001] The present invention relates to a roaster system for vegetable bulk materials, which has a housing configuration comprising: at least one roasting device having an internal space in which the bulk material can be roasted; a heating system that enables heat transport to the bulk material by means of a heating fluid in the internal space using the heating fluid; a solid matter separation device for purifying exhaust gas from the roasting device; and a control system for controlling the roasting process. The invention further relates to a method of operating such a roaster system. [[Background Art]]

[0002] Roaster systems for roasting vegetable bulk materials are known from the prior art. In this connection, reference is made, purely by way of example, to Patent Document 1 which discloses a roaster system for use in the industrial field. Conventionally, such roaster systems are provided with a gas burner as a heating system for heating the heating fluid. In particular, against the background of the shortage of energy resources and the rapid change in the cost of individual energy forms, the operation of energy-intensive roaster systems can lead to extremely high, unplannable energy costs. [[Prior Art Documents]] [[Patent Documents]]

[0003] [[Patent Document 1]] German Patent Specification No. 102004038730 [[Summary of the Invention]] [[Problem to be Solved by the Invention]]

[0004] Accordingly, it is an object of the present invention to avoid the above-described drawbacks in a simple and cost-effective manner. [[Means for Solving the Problem]]

[0005] This problem is solved by the roaster system according to the present invention, in which the heating system comprises electric heating elements and gas combustion devices, each connected to a control system for control purposes, in order to realize different heating modes and different heating outputs. In this case, the heating mode is understood to be the form of provision of heating energy. This can be done purely electrically, purely by gas, or in any mixed form, and the heating mode can be changed before or during the execution of a roasting recipe. This makes it easy, in principle, to operate the roaster system according to the present invention by electricity. In particular, when using renewable energy such as solar energy and / or wind energy, for example, operating times when the electricity derived from these renewable energy sources is not sufficiently available must be considered. In this case, the heating system can easily be operated additionally by gas. The bulk material in the internal space can be roasted by convection and / or conduction and / or by radiant heat by the heating fluid in this case. In this context, the heating system is understood to be all adjustable means that ensure heating of the bulk material, such as electric heating elements, gas combustion devices and fans, flaps, etc. The internal space is understood to consist of, for example, the internal space walls, as well as the agitator, drum, or bowl. There are numerous different roasting systems in which the internal space can have a very different structure.

[0006] In the first embodiment, the electric heating element is fluidically connected to a first heating fluid conduit, the gas combustion device is fluidically connected to a second heating fluid conduit, and the first and second heating fluid conduits are fluidically connected to a third heating fluid conduit which is fluidly connected to a roasting device. In this case, the first and second heating fluid conduits may be fluidly connected to the third heating fluid conduit via a heating fluid connecting member. Advantageously, the heating fluid connecting member may be provided with a heating mode setting flap, thereby enabling rapid switching of heating modes. Mixing operations are also possible here. To minimize any possible fluid resistance to the heating fluid, the connecting member may be particularly advantageously implemented as a Y-shaped heating fluid connecting member. Here, a connecting conduit may be provided between the electric heating element and the gas combustion device to preheat the gas combustion device. In this case, it is advantageous to provide a check valve in the connecting conduit to prevent the heating gas from reaching the electric heating element.

[0007] Alternatively, in the second embodiment, the electric heating element and the gas combustion device are arranged in fluid series, and the gas combustion device is fluidly connected to a third heating fluid conduit to the roasting device.

[0008] Particularly advantageous is that at least one basic heating output load can be generated by an electric heating element, and additional heating output loads can be generated by the electric heating element and / or a gas combustion device. This allows for the optimal use of renewable energy, in particular.

[0009] In a particularly advantageous embodiment, the bulk material within the internal space may be roasted by a heating system, convectively and / or conductively by a heating fluid, and / or by radiant heat.

[0010] In a more advantageous embodiment, a vacuum blower positioned at the rear of the roasting apparatus in the direction of the heated fluid may be provided for drawing the heated fluid from the roasting apparatus. The negative pressure present within the roasting apparatus can ensure a uniform supply of the heated fluid regardless of the heating mode.

[0011] Particularly advantageous is the provision of an air supply blower in front of the electric heating element, on the side of the electric heating element opposite to the first heating fluid pipeline.

[0012] Particularly advantageous is that the roasting apparatus includes at least one sensor mechanism for monitoring the roasting process. This makes it possible to actively adjust the roasting process, either by the user themselves when they receive a message from the control system, or automatically by the control system.

[0013] Advantageously, the heating system is fluidically connected to a first exhaust recirculation pipeline to recirculate purified exhaust gas back into the heating system, thus reducing emissions and heating the heating fluid to conserve energy. In this case, both the electric heating element and the gas combustion device may be fluidically connected to the first exhaust recirculation pipeline via a Y-shaped exhaust connection member, respectively, via second and third exhaust recirculation pipelines. To ensure an optimal supply of recirculated exhaust gas, an exhaust recirculation flap may be provided within the Y-shaped exhaust connection member.

[0014] For particularly precise heating fluid control desired in some roasting recipes, a heating fluid bypass pipeline to the exhaust pipeline with a solids separator may be provided. In this case, a heating fluid setting flap may be provided within the heating fluid bypass pipeline.

[0015] The problem can also be solved by the operation method of such a roaster system, in which the roasting mode is selected according to the roasting recipe in the control system.

[0016] Particularly advantageous is that in each roasting mode, the required basic heating power load is generated by an electric heating element, and the additional heating power load is generated by the electric heating element and / or a gas combustion device.

[0017] Advantageously, before switching the heating mode, the third heating fluid pipeline and the roasting apparatus are purged with supply air. In this case, the supply air for the purging process can be provided by the supply air blower of the electric heating element.

[0018] The present invention will be described in detail with reference to the drawings. [Brief explanation of the drawing]

[0019] [Figure 1] This is a schematic diagram of a roasting system according to the present invention, having a first embodiment of the arrangement of the electric heating element and gas combustion device of the heating system. [Figure 2] This is a schematic detail diagram of a second embodiment of the arrangement of the electric heating elements and gas combustion device of the heating system. [Modes for carrying out the invention]

[0020] Figure 1 shows a schematic diagram of a roaster system 2 according to the present invention, which is itself well known from the prior art. Such a roaster system 2 comprises a housing configuration 4 having at least one roasting device 6, a heating system 8 for heating the internal space 10 of the roasting device 6, a solids separator 12 for purifying the exhaust from the internal space 10 of the roasting device 6, and, in this embodiment, a cooling system 14 for cooling the plant bulk material to be roasted, which is coffee beans 16. In this case, unroasted coffee beans 16 are supplied to the internal space 10 of the roasting device 6 via a funnel inlet 18. In addition, a control system 20 is provided for controlling or adjusting the roasting process and the cooling process.

[0021] According to the present invention, the heating system 8 first comprises an electric heating element 22 and a gas combustion device 24, which provide a heating fluid by heating the supply air, the heating fluid being heated air in the case of the electric heating element 22 and heated gas in the case of the gas combustion device 24. In the first embodiment shown in Figure 1, a first heating fluid conduit 26 is connected to the electric heating element 22, and a second heating fluid conduit 28 is connected to the gas combustion device 24. These are fluidically connected to a third heating fluid conduit 32 via a Y-shaped heating fluid connecting member 30, and the third heating fluid conduit 32 leads the heating fluid to the roasting device 6.

[0022] On the side of the electric heating element 22 opposite to the first heating fluid conduit 26, an air supply blower 34 is provided in front of the electric heating element 22 so that a uniform heating fluid flow can be ensured. Furthermore, reliable cooling of the electric heating element 22 is guaranteed under all operating conditions. The gas combustion device 24 also comprises a fan 36 in a known manner. Furthermore, in order to preheat the supply air of the gas combustion device 24, a connecting conduit 40 having a check valve 42 is provided from the electric heating element 22 to the supply air inlet 38 of the fan 36. In order to enable different heating modes to be set, the Y-shaped heating fluid connecting member 30 is also provided with a heating mode setting flap 44. The third heating fluid conduit 32 further comprises a heating fluid flap 44, which, together with an exhaust flap 48 and a negative pressure fan 50, as part of the heating system 8, together with the aforementioned means 22 to 44, influences the heating fluid mass flow rate, exhaust mass flow rate and temperature of the roasting process. In this embodiment, heat transfer to the coffee beans 16 is performed convectively, conductively, and by radiant heat.

[0023] In this embodiment, the cooling system 14 consists of a cooling device 52 having a flatbed cooler 54, onto which the coffee beans 16 are poured through the outlet opening 56 of the roasting device 6. In this case, the flatbed cooler 54, together with a hood structure 58, encloses a cooling space 60 into which cooling air is blown by a cooling air device 62. A bulk material outlet structure 64 and a cooling air exhaust device 66 are connected to the cooling device 52 in a known manner.

[0024] In this embodiment, the temperature of the coffee beans 16 in the inner space 10 of the roasting device 6 is monitored by a sensor arrangement 67, which is advantageously constructed in a non-contact manner herein.

[0025] As described above, an exhaust gas purification device 12 is provided, which can purify the exhaust gas in a well-known manner and release it into the surroundings. However, a first exhaust gas recirculation pipeline 68 is also provided, which is fluidly connected to the second and third exhaust gas recirculation pipelines 78, 80 via a Y-shaped exhaust connection member 74 having an exhaust gas recirculation flap 76 to return the exhaust gas to the electrical inlet area 79 of the electric heating element 22 and / or the gas inlet area 81 of the gas combustion device 24 in order to preheat the respective supply air.

[0026] To allow for additional configurability for rapid adjustments within the roasting process, a heating fluid bypass pipe 82 is provided to the exhaust purification device 12, which also has a heating fluid setting flap 84.

[0027] Figure 2 shows a detailed view of a second embodiment of the roaster system 3, in which an alternative arrangement of the electric heating element 23 and the gas combustion device 25 of the heating system 9 is provided. All other components of the roaster system 2 remain unchanged. Although Figure 2 shows a detailed view with only a few components, reference numeral 3 for the roaster system and reference numeral 9 for the heating system are introduced to show the differences from the roaster system 2 and heating system 9 shown in Figure 1. In this case, the electric heating element 23 and the gas combustion device 25 are fluidically arranged in series via a heating fluid connection line 86, and the gas combustion device is fluidically connected to a third heating fluid line 32 to the roaster 6. In this case as well, both the electric heating element 23 and the gas combustion device 25 are connected to the control system 20, as shown by the dashed lines. In this embodiment, the electrical inlet region 79 of the electric heating element 23 is connected to a first exhaust recirculation line 68. This also enables exhaust recirculation to the gas combustion device 25.

[0028] In this regard, it should be noted that exhaust gas recirculation is not always necessary. In particular, it is possible to connect only the electric heating elements 22;23 to the exhaust gas recirculation pipeline 68.

[0029] In order to allow the roasting systems 2 and 3 to be controlled as flexibly as possible, in this embodiment the control system 20 is connected to many components such as electric heating elements 22 and 23, gas combustion devices 24 and 25, roasting device 6, sensor mechanism 67, and various dampers and blowers or fans.

[0030] With such roasting systems 2;3, a corresponding roasting mode can be selected based on a roasting recipe stored in the control unit. In this case, the required basic heating power load for each roasting mode can be generated by electric heating elements 22;23. Any additional heating power load required is then generated by the electric heating elements 22;23 and / or by gas combustion devices 24;25, depending on the existing energy boundary conditions.

[0031] It has been proven particularly effective to purge the third heating fluid pipeline 32 and the roasting apparatus 6 with supply air before switching the roasting recipe. In this case, the supply air for the purging process can be provided by the supply air blower 34 of the electric heating elements 22;23.

Claims

1. A roasting system for a plant-based bulk material (16) having a housing configuration (4), the housing configuration (4) comprising: at least one roasting device (6) having an internal space (10) in which the bulk material (16) can be roasted; a heating system (8; 9) enabling heat transport to the bulk material (16) within the internal space (10) using a heating fluid; a solids separator for purifying exhaust from the roasting device (6); and a control system (20) for controlling the roasting process, wherein the heating system (8; 9) comprises electric heating elements (22; 23) and gas combustion devices (24; 25), each connected to the control system (20) for control purposes, to achieve different heating modes and different heating outputs.

2. The roasting system according to claim 1, wherein the electric heating element (22) is fluidly connected to a first heating fluid line (26), the gas combustion device (24) is fluidly connected to a second heating fluid line (28), and the first and second heating fluid lines (26, 28) are fluidly connected to a third heating fluid line (32) which is fluidly connected to the roasting device (6).

3. The roasting system according to claim 2, wherein the first and second heating fluid lines (26, 28) are fluidly connected to the third heating fluid line (32) via a heating fluid connecting member (30).

4. The roasting system according to claim 3, wherein a heating mode setting flap (44) is provided within the heating fluid connecting member (30).

5. The roasting system according to claim 3 or 4, wherein the heating fluid connecting member (30) is embodied as a Y-shaped heating fluid connecting member.

6. The roasting system according to any one of claims 2 to 5, wherein a connecting pipe (40) is provided between the electric heating element (22) and the gas combustion device (24).

7. The roasting system according to claim 6, wherein a check valve (42) is provided inside the connecting pipe (40).

8. The roasting system according to claim 1, wherein the electric heating element (23) and the gas combustion device (25) are arranged in series in a fluid manner, and the gas combustion device (25) is fluidly connected to the third heating fluid pipeline (32) to the roasting device (6).

9. A roasting system according to any one of claims 1 to 8, wherein at least one basic heating output load can be generated by the electric heating elements (22; 23), and an additional heating output load can be generated by the electric heating elements (22; 23) and / or the gas combustion device (24; 25).

10. The roasting system according to any one of claims 1 to 9, wherein the bulk material (16) in the internal space (10) can be roasted by the heating system (8; 9) using the heating fluid convectively and / or conductively and / or by radiant heat.

11. The roasting system according to any one of claims 1 to 10, wherein a vacuum blower (50) is provided to suck the heated fluid from the roasting device (6), with respect to the direction of the heated fluid, and is positioned behind the roasting device (6).

12. The roasting system according to any one of claims 1 to 11, wherein an air supply blower (16) is provided in front of the electric heating elements (22; 23) on the side opposite to the first roasting apparatus (6).

13. The roasting apparatus (6) comprises at least one sensor mechanism (67) for monitoring the roasting process, according to any one of claims 1 to 12.

14. The roasting system according to any one of claims 1 to 13, wherein the heating system (8; 9) is fluidly connected to a first exhaust recirculation pipe (68).

15. The roasting system according to claim 14, wherein both the electric heating elements (22; 23) and the gas combustion devices (24; 25) are fluidly connected to the first exhaust recirculation pipe (68) via a Y-shaped exhaust connecting member (74) through second and third exhaust recirculation pipes (78, 80), respectively.

16. The roasting system according to claim 15, wherein an exhaust recirculation flap (76) is provided inside the Y-shaped exhaust connecting member (74).

17. The roasting system according to any one of claims 1 to 16, wherein a heating fluid bypass pipe (82) is provided to the exhaust pipe having the solid separation device (12).

18. The roasting system according to claim 17, wherein a heating fluid setting flap (84) is provided in the heating fluid bypass pipe (82).

19. A method for operating a roasting system according to claims 1 to 18, wherein a roasting mode is selected within the control system (20) according to a roasting recipe.

20. A method for operating the roasting system according to claim 1, wherein in each roasting mode, the required basic heating output load is generated by the electric heating elements (22; 23), and the additional heating output load is generated by the electric heating elements (22; 23) and / or the gas combustion device (24; 25).

21. The method of operating the roaster system according to claim 19 or 20, wherein the third heating fluid pipeline (32) and the roasting apparatus (6) are purged with supply air before switching the heating mode.

22. The method of operating the roaster system according to claim 21, wherein the supply of air for the purging process is provided by the supply air blower (16) of the electric heating elements (22; 23).

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