Clinker cooler with gas partition wall
Patent Information
- Application Number
- EP2024709358
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-03-21
- Filing Date
- 2024-03-04
- Publication Date
- 2026-01-28
AI Technical Summary
In cement clinker production, the separation between recuperation gas and cooler exhaust air in clinker coolers is critical for the oxyfuel process, but previous designs lacked stabilization of the apex between these gas flows, leading to thermal and abrasive wear issues with partition walls.
A clinker cooler with a gas partition system using adjustable gas nozzles to create a controlled gas partition between the recuperation and cooling areas, utilizing carbon dioxide-rich process gas and atmospheric air, and a control device to optimize the partition's position based on pressure and flow dynamics.
The gas partition effectively stabilizes the apex between recuperation and cooler exhaust air, reducing thermal and abrasive wear on partition walls, enhancing the separation efficiency and longevity of the clinker cooler components.
Smart Images
Figure EP2024055533_26092024_PF_FP
Abstract
Description
[0001] Clinker cooler with gas partition
[0002] The invention relates to a clinker cooler for cooling freshly sintered cement clinker in a plant for producing cement clinker, comprising a first part located upstream in the direction of material flow, and a second part located downstream in the direction of material flow, wherein both parts have a continuous grate through which cooling gas can flow from below via cooling gas supply lines and on which the cement clinker lies in a bed for cooling, wherein the entire grate in both parts is continuously enclosed by a housing with housing walls and a housing ceiling.
[0003] Cement clinker production plants are currently being converted to an operation that recirculates carbon dioxide-rich process gas. A portion of the process gas is continuously removed for permanent storage and replaced with new process gas. This very brief description describes the so-called oxyfuel process for cement clinker production. A critical area for sealing the plant is the clinker cooler used in generic plants for the production of cement clinker. In clinker coolers, there is a front area near the inlet to the rotary kiln head where high temperatures prevail and where cooling gas is returned to the plant as recuperation gas. The cooler then transitions into a zone where the cooling air is no longer hot enough to allow effective recuperation. The cooling air heated here is generally discarded as cooler exhaust air.Between the recuperation zone of a clinker cooler and the subsequent cooling zone, there is an invisible boundary with a peak of the gas flow direction. In the recuperation zone, the gas flows back into the system. In the cooling zone, the gas flows out of the cooler. Between the recuperation zone and the cooling zone, there is a stationary boundary with no flow movement. In previous clinker coolers, little attention was paid to this peak because a mixture of recuperation air and cooler exhaust air was not significant. With the introduction of the oxyfuel process, in which carbon dioxide-rich process gas is to be captured, stored, or further utilized to avoid carbon dioxide emissions, the separation between recuperation gas and atmospheric air in the cooler zone has become important.For this purpose, a downwardly open partition is usually installed in the radiator, which enforces stabilization of the peak. However, these partitions are subject to very high thermal and abrasive wear. Therefore, there is a need to stabilize the peak between the recuperation gas and the radiator exhaust air in the radiator.
[0004] The object of the invention is therefore to provide a clinker cooler with a stabilization of the peak point between recuperation gas and cooler exhaust air in the cooler.
[0005] The object of the invention is achieved by a clinker cooler having the features of claim 1. Further advantageous embodiments are specified in the subclaims to claim 1.
[0006] The invention is explained in more detail with reference to the following figures. They show:
[0007] Fig. 1 is a perspective view of the longitudinal side of a clinker cooler according to the invention,
[0008] Fig. 2 a view into the clinker cooler in the area of the gas partition wall between levels A and B in Figure 1
[0009] Figure 1 shows a broken-away view of the long side of a clinker cooler 100 according to the invention. The clinker cooler 100 serves to cool freshly sintered cement clinker 101 in a cement clinker production plant (not shown here). The clinker cooler 100 has a recuperation zone on the left side in this illustration and corresponds to a first part 110 of the clinker cooler 100, located upstream in the material flow direction. In the recuperation zone, cooling gas 132 blown from below through a grate 130 is heated by the hot cement clinker 101, and this cooling gas 132 is then returned to the cement clinker production plant as secondary air and tertiary air. The terms "secondary air" and "tertiary air" are clearly defined terms in the cement industry. Furthermore, the clinker cooler 100 has a second part 120 located downstream in the material flow direction.In this section, the already significantly cooled cement clinker 101 is cooled with atmospheric air to a temperature below 100°C, so that the cement clinker is ready for storage or can be handled for further grinding. Both sections 110 and 120 of the clinker cooler 100 have a continuous grate 130, through which cooling gas 132 flows from below via cooling gas supply lines 131, and on which the cement clinker 101 lies in a bed for cooling. The entire grate 130 in both sections 110 and 120 of the clinker cooler 100 is continuously enclosed by a housing 140 with housing walls 141 and a housing ceiling 142, with the housing walls 141 and the housing ceiling 142 being shown in perspective in Figure 2.
[0010] Between the recuperation area, i.e. the first part 110 located upstream in the material flow direction, and the second part 120 located downstream in the material flow direction, gas nozzles 150 are arranged in the housing walls 141 and in the housing ceiling 142 in at least one Roman I, Roman II or Roman III plane, 160, 161, 162, which is arranged perpendicular to the direction of the material flow, wherein the at least one Roman I, Roman II or Roman III plane, 160, 161, 162 of the gas nozzles 150 divides the clinker cooler 100 into the first part 110 and the second part 120. The gas nozzles 150 blow carbon dioxide-rich process gas perpendicular to the conveying direction of the grate 130 into the closed clinker cooler 100 and thus form a gas partition wall made of process gas.This gas partition wall, shown in Figure 1 as a dotted area in front of the gas nozzles shown here in Roman numeral I, 160, separates the atmospheric air for cooling in the second part 120 of the clinker cooler 100 from the process gas used as cooling gas in the first part 110 of the clinker cooler 100, where recuperation takes place. Ideally, the gas partition wall is positioned exactly where the apex of the gas flow direction of the carbon dioxide-rich process gas and the atmospheric air used as cooling air is located. In Figure 1, curved arrows show that in the first part 110 of the clinker cooler 100, the carbon dioxide-rich process gas flows over the cement clinker 101 to the left into the recuperation area of the cooler 100, while in the second part 120, the atmospheric air used as cooling air flows to the right as cooler exhaust air.The gas partition wall is arranged in the middle between the two gas flow directions and is located in plane 160 in the example shown here.
[0011] The spatial position of the peak of the gas flow depends on a variety of factors. In order to be able to adjust the position of the gas partition, an advantageous embodiment of the invention provides for the gas nozzles 150 to be arranged in at least two parallel planes (Roman I, Roman II, or Roman III, 160, 161, 162). Thus, by activating valves 220, one or the other plane (Roman I, Roman II, or Roman III, 160, 161, 162) of the gas nozzles 150 can be activated, and the gas partition can be activated at different points. The gas nozzles 150 are connected via a compressor 170 to a process gas line 180 to the cement clinker production plant, which carries carbon dioxide-rich process gases from the plant to the gas nozzles 150.The cooling gas supply lines 131 in the first part 110 of the clinker cooler 100, located upstream in the material flow direction, are also connected via at least one compressor 190 to a process gas line 180 leading to the cement clinker production plant. This process gas line carries carbon dioxide-rich process gases from the plant to the cooling gas supply lines 131. The cooling gas supply lines 131 in the second part 120, located downstream in the material flow direction, are connected via a compressor 191 to a cooling air line 195, which carries atmospheric air to the cooling gas supply lines 131.During transport over the continuous grate 130 through the clinker cooler, the cement clinker is first cooled with process gas, which flows back to the left through the gas partition wall into the heat recovery plant in the cement clinker production plant, and then the cement clinker, which is conveyed under the gas partition wall, is cooled with atmospheric air in the second part 120 of the clinker cooler 100.
[0012] The optimal spatial position of the gas partition wall created by the gas nozzles 150 in the planes 160, 161, 162 depends on the system pressure, the gas flow velocity in the clinker cooler, and the resulting Bernoulli negative pressures generated by the flow. The flow dynamics, in particular, depend on geometric conditions in the clinker cooler 100. A control device 200, which is part of the clinker cooler 100, is connected, in the embodiment shown here, to pressure sensors 210 in the housing walls 141 in the first part 110 located upstream in the material flow direction, and in the second part 120 located downstream in the material flow direction. The control device 200 controls valves 220 which control the gas flow through the gas nozzles 150 in the at least two parallel planes Roman I, Roman II or Roman III, 160, 161, 162.Depending on the pressure measured by the pressure sensors 210 in both parts 110 and 120 of the clinker cooler 100, the control device 200 opens the gas nozzles 150 in a Roman I, Roman II, or Roman III, 160, 161, 162 plane by controlling the valves 220. This plane enlarges precisely that part 110 or 120 of the clinker cooler 100 in which a higher pressure prevails compared to the current Roman I, Roman II, or Roman III, 160, 161, 162 plane of the gas nozzles 150, and vice versa. If the pressure in one of the two parts 110 and 120 of the clinker cooler 100 is increased, the spatial position of the gas partition wall is shifted such that precisely that part 110 and 120 of the clinker cooler 100 with the higher pressure is enlarged. In this way, the gas partition wall is shifted towards the apex of the gas flow direction.If the displacement of the gas partition wall by opening and closing the corresponding valves 220 of the gas nozzles 150 is not sufficient to reach the apex, it can further be provided that the control device 200 controls compressors 190, 191 to the cooling gas supply lines 131 in both parts 110, 120 of the clinker cooler 100, so that the pressure in both parts 110, 120 of the clinker cooler 100 is the same.
[0013] When the position of the gas partition wall is shifted, cooling gas injected into the clinker cooler 100 from below, namely process gas or atmospheric air, can flow into the 'wrong' part 110 or 120 of the clinker cooler 100. To prevent this false gas entry, it can be provided that a cooling air supply line 133 can be supplied with atmospheric air or with carbon dioxide-rich process gas from the cement clinker production plant through a switching valve 151, with a deviation of up to 10% of the length of the cooler in the Roman I, Roman II, or Roman III, 160, 161, 162 plane of the gas nozzles 150. In this case, one cooling air supply line 133 can be supplied with either atmospheric air or carbon dioxide-rich process gas from the cement clinker production plant, or several cooling air supply lines 133 can be supplied with the aforementioned deflection, which are arranged in the area of the gas partition walls.
[0014] The position of the Roman I, Roman II, or Roman III planes, 160, 161, and 162, must be determined during construction of the clinker cooler. Typically, the aforementioned apex of the gas flow direction is located approximately in the center of the clinker cooler 100, so that the two parts 110 and 120 of the clinker cooler 100 are approximately the same size. However, to compensate for deviations in the position of the apex, it can be provided that at least one Roman I, Roman II, or Roman III plane, 160, 161, 162, of the gas nozzles 150 is arranged centrally with a deviation of up to 20% of the length of the cooler 100, so that the two parts 110, 120 of the clinker cooler 100 are correspondingly large.
[0015] Figure 2 shows a view into the clinker cooler in the area of the gas partition wall between levels A and B, which are shown in Figure 1. For this purpose, the area of the clinker cooler 100 between levels A and B shown in Figure 1 is shown in a perspective view, looking from level A to level B, with the housing walls 141 and the housing ceiling 142 being visible. In the illustration shown here, the frontmost level, i.e. level Roman I or 160, is activated. Activation is represented by the dashed boundary. The dotted line indicates the injection of process gas as a gas partition wall. The dotted line thus corresponds to a gas partition wall. The individual gas nozzles 150 are supplied with process gas by compressors 180, with valves 220 being controlled by a controller 200 to activate the respective level Roman I, Roman II or Roman III, 160, 161, 162.
[0016] LIST OF REFERENCE SYMBOLS
[0017] Clinker cooler 161 level
[0018] Cement clinker 162 Level first part 170 Compressor second part 180 Process gas line
[0019] Rost 190 compressor
[0020] Cooling gas supply line 195 Cooling air line
[0021] Cooling gas 200 control device
[0022] Cooling gas supply line 210 pressure sensor
[0023] Housing 220 valve
[0024] Housing wall
[0025] Housing ceiling A level
[0026] Gas nozzle B level
[0027] level
Claims
Clinker cookers with Gastrenwall PATENTANSPR Ü CHE 1 . Clinker cooler (100) for cooling freshly sintered cement clinker (101) in a plant for producing cement clinker, comprising a first part (110) located upstream in the material flow direction, and a second part (120) located downstream in the material flow direction, wherein both parts (110, 120) have a continuous grate (130) through which cooling gas (132) can flow from below via cooling gas supply lines (131) and on which the cement clinker (101) lies in a bed for cooling, wherein the entire grate (130) in both parts (110, 120) is continuously enclosed by a housing (140) with housing walls (141) and a housing cover (142), characterized in that between the first part (110) located upstream in the material flow direction, and the second part (120) located downstream in the material flow direction, in the housing walls (141) and in the housing ceiling (142) gas nozzles (150) in at least one plane (160, 161, 162) which is arranged perpendicular to the direction of the material flow, wherein the at least one plane (160, 161, 162) of the gas nozzles (150) divides the clinker cooler (100) into the first part (110) and the second part (120).
2. Clinker cooler according to claim 1, characterized in that the gas nozzles (150) are arranged in at least two parallel planes (160, 161, 162).
3. Clinker cooler according to claim 1 or 2, characterized in that the gas nozzles (150) are connected via a compressor (170) to a process gas line (180) to the plant for producing cement clinker, which process gas line carries carbon dioxide-rich process gases from the plant to the gas nozzles (150).
4. Clinker cooler according to one of claims 1 to 3, characterized in that the cooling gas supply lines (131) in the first part (110) located upstream in the material flow direction are connected via at least one compressor (190) to a process gas line (180) to the plant for producing cement clinker, which process gases rich in carbon dioxide from the plant to the cooling gas supply lines (131).
5. Clinker cooler according to one of claims 1 to 4, characterized in that the cooling gas supply lines (131) in the second part (120) located downstream in the material flow direction are connected via a compressor (191) to a cooling air line (195) which leads atmospheric air to the cooling gas supply lines (131).
6. Clinker cooler (100) according to one of claims 2 to 5, dependent on claim 2, characterized in that a control device (200), which is part of the clinker cooler (100), is connected to pressure sensors (210) in the housing walls (141) in the first part (110) located upstream in the material flow direction, and in the second part (120) located downstream in the material flow direction, wherein the control device (200) controls valves (220) which control the gas flow through the gas nozzles (150) in the at least two parallel planes (160, 161, 162), and wherein the control device (200) in dependence on the pressure measured by the pressure sensors (210) in both parts (110, 120) of the clinker cooler (100) by controlling the valves (220) opens the gas nozzles (150) in a plane (160, 161, 162) which forms the part (110, 120) of the Clinker cooler (100) is enlarged compared to the current level (160, 161, 162) of the gas nozzles (150), in which a greater pressure prevails and vice versa.
7. Clinker cooler according to claim 6, characterized in that the control device (200) controls compressors (190, 191) to the cooling gas supply lines (131) in both parts (110, 120) of the clinker cooler (100) so that the pressure in both parts (110, 120) of the clinker cooler (100) is the same.
8. Clinker cooler according to one of claims 1 to 7, characterized in that the cooling air supply lines (133) can be supplied with atmospheric air or with carbon dioxide-rich process gas from the plant for producing cement clinker by means of a changeover valve (151) with a deviation of up to 10% of the length of the cooler in the plane of the gas nozzles (150).
9. Clinker cooler according to one of claims 6 to 8, dependent on claim 6, characterized in that the switching valves (151) for the cooling air supply lines (132) can be controlled by the control device (200) with a deviation of up to 10% of the length of the cooler (100) in the plane (160, 161, 162) of the gas nozzles (150).
10. Clinker cooler according to one of claims 1 to 9, characterized in that the at least one plane (160, 161, 162) of the gas nozzles (150) are arranged centrally with a deviation of up to 20% of the length of the cooler (100), so that the two parts (110, 120) of the clinker cooler (100) are of corresponding size.