Flow regulating device and flow regulating method for slurry delivery pipe of wet desulphurization process

Abstract

The present application relates to desulfurization processing technical field, specifically to the flow regulating device and flow regulating method for slurry conveying pipeline of wet desulfurization process, the device comprises: desulfurization tower equipment for desulfulfurization and generating gypsum in slurry pool;Buffer container is connected with slurry pool through first pipeline, for conveying slurry in slurry pool to the buffer container.The present application increases a shut-off valve and a flow limiting orifice plate on the second pipeline on the original structure, when the shut-off valve of main pipeline is closed, the working medium only passes through the flow limiting orifice plate, due to the throttling of the flow limiting orifice plate, the pipeline conveying capacity meets the processing capacity of one dewatering equipment, and the working medium flow dead zone before and after the shut-off valve is extremely short, the flow limiting orifice plate is installed above the shut-off valve, therefore, slurry plugging phenomenon does not occur, the overall cost is low, and the greater the slurry conveying capacity, the more investment can be saved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of desulfurization treatment, in particular to a flow regulating device and a flow regulating method for a slurry conveying pipeline of a wet desulfurization process. BACKGROUND

[0002] In the wet desulfurization process, gypsum is a by-product existing in the slurry pool of the desulfurization tower. The continuously generated gypsum slurry needs to be sent to a dewatering system for dewatering to obtain dewatered gypsum, which becomes a building material that can be conveniently transported. The gypsum slurry conveying is generally pumped, as shown in the accompanying drawings, because the yield of desulfurization gypsum will fluctuate with the fluctuation of the boiler flue gas load, and the change range is relatively large. Figure 1

[0003] Therefore, a buffer tank is generally arranged upstream of the gypsum slurry conveying pump to adapt to such fluctuation as much as possible. Downstream of the gypsum slurry conveying, two sets of dewatering equipment are generally arranged, and the total load of the two sets of dewatering equipment is defined as 200% load. The yield of gypsum is determined according to the density of the slurry pool of the desulfurization tower. When the yield of gypsum is large (generally greater than 75% load), two dewatering devices need to be operated simultaneously or one is continuously operated and the other is intermittently operated. When the load is low (generally less than 75% load), one device is continuously or intermittently operated.

[0004] The gypsum slurry conveying supply must be able to meet the amount of one set of dewatering system operation and the amount of two sets of dewatering equipment simultaneous operation. The traditional flow regulating control has the following several kinds: (1) the slurry conveying pump adopts frequency regulation; (2) a slurry regulating ball valve is adopted; (3) a separate slurry supply pipeline is established for each set of dewatering equipment. These three processing methods can well meet the requirements in the process, but the cost is relatively high, all above ten thousand yuan, especially the second and third schemes, the cost is at least more than 50,000 yuan. SUMMARY

[0005] According to a first aspect of the object of the present application, a flow regulating device for a slurry conveying pipeline is provided, which is particularly suitable for slurry conveying control in a wet desulfurization process, and the flow regulating device comprises:

[0006] a desulfurization tower device for desulfurization and generating gypsum in a slurry pool;

[0007] a buffer container connected with the slurry pool through a first pipeline, for conveying the slurry in the slurry pool to the buffer container;

[0008] ​The gypsum dehydration device is connected with the buffer container through a second pipeline, a delivery pump is arranged on the second pipeline, the gypsum dehydration device comprises a first dehydration device and a second dehydration device, two branch pipes are arranged at the end of the second pipeline and are connected to the first dehydration device and the second dehydration device respectively.

[0009] The second pipeline is provided with an adjusting component, and the adjusting component is arranged to include a first state and a second state, wherein:

[0010] In the first state of the adjusting component, the upper limit of the flow of the second pipeline is less than or equal to the dehydration flow of the first dehydration device or the second dehydration device.

[0011] In the second state, the upper limit of the flow of the second pipeline is less than or equal to the total dehydration flow of the first dehydration device and the second dehydration device.

[0012] As an optional embodiment, the adjusting component comprises a shut-off valve and a flow-limiting orifice plate, the shut-off valve and the flow-limiting orifice plate are connected to the second pipeline in parallel, so that at least one flow control channel is formed in the second pipeline during the process in which the medium in the buffer container is pumped into the second pipeline by the delivery pump and delivered to the gypsum dehydration device, one of the flow control channels is controlled by the shut-off valve, and the other is controlled by the flow-limiting orifice plate.

[0013] As an optional embodiment, when the adjusting component is in the first state, the shut-off valve is in a closed state, and the medium in the second pipeline flows from the flow-limiting orifice plate.

[0014] When the adjusting component is switched to the second state, the shut-off valve is in an open state, and the medium in the second pipeline flows through the flow-limiting orifice plate and the shut-off valve at the same time.

[0015] As an optional embodiment, the flow-limiting orifice plate is located above the shut-off valve.

[0016] As an optional embodiment, when the power of the first dehydration device and the second dehydration device is the same, and each dehydration device has the same maximum processing capacity, the upper limit of the flow of the flow-limiting orifice plate is less than or equal to the dehydration flow of the first dehydration device or the second dehydration device.

[0017] As an optional embodiment, the shut-off valve is a butterfly valve.

[0018] As an optional embodiment, the flow-limiting orifice plate comprises a wear-resistant alloy plate and a through hole is arranged in the center of the wear-resistant alloy plate.

[0019] As an optional embodiment, a stirrer is arranged in the buffer container, and the stirrer is used to mix the medium in the buffer container.

[0020] As an optional embodiment, a concentration monitoring sensor is arranged in the slurry pool of the desulfurization tower device to detect the medium concentration.

[0021] When the detected medium concentration is greater than a preset value, the adjusting component is controlled to be in the second state, and when the medium concentration in the slurry pool is less than or equal to the preset value, the adjusting component is controlled to switch to the first state.

[0022] According to a second aspect of the object of the present application, a slurry delivery flow adjusting method for a wet desulfurization process is also provided, which comprises the following steps:

[0023] Monitoring the medium concentration in the slurry pool of the desulfurization tower device to determine the amount of gypsum in the slurry in the slurry pool;

[0024] According to the monitored medium concentration, the pumping from the buffer container to the gypsum dewatering device and the operation of the gypsum dewatering device are controlled, wherein:

[0025] When the monitored medium concentration in the slurry pool is greater than a preset value, the adjusting component is controlled to be in the second state, so that the shutoff valve is in the open state, the medium flowing in the second pipeline flows through the orifice plate and the shutoff valve at the same time, the upper limit of the flow of the second pipeline is less than or equal to the total dewatering flow of the first dewatering device and the second dewatering device, and the first dewatering device and the second dewatering device are controlled to be started to perform gypsum dewatering treatment at the same time;

[0026] When the monitored medium concentration in the slurry pool is less than or equal to the preset value, the adjusting component is controlled to switch to the first state, the shutoff valve is controlled to switch to the shutoff state, and the medium flowing in the second pipeline only flows through the orifice plate, so that the upper limit of the flow of the second pipeline is less than or equal to the dewatering flow of the first dewatering device or the second dewatering device, and the first dewatering device or the second dewatering device is controlled to be started to perform gypsum dewatering treatment.

[0027] Compared with the prior art, the slurry delivery pipeline flow adjusting device provided by the present application only adds a shutoff valve and an orifice plate to the second pipeline on the basis of the existing pumping dewatering system. When the shutoff valve of the main pipeline is closed, the medium only flows through the orifice plate. Due to the throttling of the orifice plate, the pipeline delivery amount meets the processing amount of one dewatering device, and the flow dead zones before and after the shutoff valve are extremely short. The orifice plate is installed above the shutoff valve, so that the slurry plugging phenomenon does not occur. The overall cost is only about 5000 yuan, and the larger the slurry delivery amount is, the more investment can be saved. BRIEF DESCRIPTION OF DRAWINGS

[0028] The drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures can be represented by a like numeral. For purposes of clarity, not every component can be called out in every drawing. Embodiments of various aspects of the present application will now be described, by way of example only, with reference to the drawings.

[0029] Figure 1 is a schematic diagram of a flow regulating device of a slurry conveying pipeline in the prior art.

[0030] Figure 2 is a schematic diagram of a flow regulating device of a slurry conveying pipeline in an embodiment of the present application.

[0031] Figure 3 is a control schematic diagram of a flow regulating device in an embodiment of the present application. DETAILED DESCRIPTION

[0032] In order to better understand the technical content of the present application, specific embodiments are described below with reference to the accompanying drawings.

[0033] In combination Figure 1 as shown, taking the slurry conveying in the limestone-gypsum wet desulfurization process of a coal-fired power plant as an example for description.

[0034] The gypsum slurry generated by flue gas desulfurization is generated in the slurry pool of the desulfurization tower equipment 1. Due to the large fluctuation during flue gas treatment, the concentration of gypsum in the slurry pool changes. Using only one dewatering device to treat the gypsum slurry cannot meet the requirements. Usually, two dewatering devices are used to treat gypsum, and the working state of the two dewatering treatment devices is determined according to the concentration of the gypsum slurry in the slurry pool. For example, when the gypsum production is greater than 75% of the load, two dewatering devices need to run simultaneously, or one continuously and the other intermittently. When the gypsum production is less than 75% of the load, one device continuously or intermittently runs. It can be seen that this treatment method involves the state control of the dewatering device, and at the same time, the flow of the conveying pipeline needs to be controlled. The current transformation cost of the control such as frequency conversion control of the conveying pump and adjustment ball valve is relatively high. The present application aims to reduce the flow regulation cost and realize the regulation of the flow to meet the amount of one set of dewatering system running, and also to meet the amount of two sets of dewatering devices running simultaneously.

[0035] In combination Figure 2 as described above, the present application proposes a flow regulating device of a slurry conveying pipeline, which comprises a desulfurization tower equipment 1, a buffer container 3, a conveying pump 4 and a regulating component.

[0036] In the wet desulfurization process, gypsum is a byproduct, which is produced in the slurry tank during the desulfurization process of the desulfurization tower equipment 1. In order to determine the amount of gypsum produced, a concentration monitoring sensor is arranged in the slurry tank. When the gypsum production is high, the concentration of the slurry tank increases, and vice versa. Therefore, the gypsum production can be obtained by detecting the concentration of the slurry tank.

[0037] Therefore, in the embodiment of the present application, according to the amount of gypsum production, it can be determined whether to start one or two dewatering devices.

[0038] Preferably, the two dewatering devices have the same power, each dewatering device has the same maximum treatment capacity, and the load of the two devices at the maximum treatment capacity is 200%. According to the relevant design requirements, when the gypsum production is greater than 75% load, two dewatering devices need to be operated simultaneously, or one is continuously operated and the other is intermittently operated. When the load is less than 75%, one device is continuously or intermittently operated.

[0039] In combination Figure 1 As shown in the figure, the buffer container 3 is connected with the slurry tank through the first pipeline 2, which is used to transport the slurry in the slurry tank of the desulfurization tower equipment 1 to the buffer container 3.

[0040] The gypsum dewatering device is connected with the buffer container 3 through the second pipeline 5, and the buffer container 3 is used to buffer the flow change in the pipeline.

[0041] A delivery pump 4 is arranged on the second pipeline 5, which pumps the slurry in the buffer container.

[0042] The gypsum dewatering device includes a first dewatering device 61 and a second dewatering device 62, in combination Figure 1 As shown in the figure, two branch pipes are arranged at the end of the second pipeline 5, which are connected to the first dewatering device and the second dewatering device, respectively.

[0043] Among them, the buffer container 3 is provided with a stirrer 31 driven by a motor to rotate and operate, which is used to mix the medium in the buffer container 3.

[0044] In combination Figure 1 According to the example of the present application, an adjusting component is arranged on the second pipeline 5, which can be set in at least one first state and second state:

[0045] In the first state, the upper limit of the flow of the second pipeline 5 is less than or equal to the dewatering flow of the first dewatering device or the second dewatering device;

[0046] In the second state, the upper limit of the flow of the second pipeline 5 is less than or equal to the total dewatering flow of the first dewatering device and the second dewatering device.

[0047] As an optional embodiment, the regulating component is electrically connected with a regulating controller 80, which controls and switches the state of the regulating component. The regulating controller 80 can be implemented based on an embedded control system or an industrial control computer system. It should be understood that the regulating controller 80 has a data storage, a processing, and a human-machine interface input-output interface capable of being input by an operator and a display capable of providing visual feedback for displaying the state information of the object received and / or processed by the pulp slurry delivery flow regulating device of the embodiment of the present application.

[0048] As an optional example, when the gypsum production is less than 75% load, the control regulating component is in the first state, which can allow the flow less than 75% load of a single dewatering device to pass through. When the gypsum production is greater than 75% load, the regulating controller 80 controls the regulating component to switch to the second state, allowing the flow exceeding 75% load to pass through, so that only two actions are required to meet the dewatering requirements of two devices.

[0049] In a preferred embodiment, the regulating component includes a shut-off valve 71 and a flow-limiting orifice plate 72, which are connected in parallel to the second pipeline 5, i.e., in the process of pumping the medium in the buffer container 3 to the second pipeline 5 for delivery to the dewatering device via the delivery pump 4, there are at least two flow switches in the second pipeline, one of which is controlled by the shut-off valve 71 and the other is controlled by the flow-limiting orifice plate 72.

[0050] In the embodiment of the present application, the flow-limiting orifice plate 72 is configured to design the size of the through-hole according to the predetermined flow and load, which adopts a structure form of a 3mm thick wear-resistant alloy plate with a through-hole in the center. In the example of the present application, the size of the through-hole is designed for a maximum of 75% load of the medium flowing through. Of course, in other embodiments, the aforementioned load amount can also be adjusted as needed.

[0051] That is, when the regulating component is in the first state, the shut-off valve 71 is in the closed state, and the medium in the second pipeline 5 flows through the flow-limiting orifice plate 72. Thus, the maximum flow of the medium through the flow-limiting orifice plate 72 is 75% load, which is sufficient to meet the operation requirements of a dewatering device.

[0052] It should be understood that the upper limit of the flow of the flow-limiting orifice plate 72 should be less than or equal to the dewatering flow of the first dewatering device or the second dewatering device, and in the case that the power of the first dewatering device and the second dewatering device is the same, each dewatering device has the same maximum processing capacity.

[0053] When the adjusting component switches to the second state, the shutoff valve 71 is in the open state, and the medium in the second pipeline 5 flows through the flow-restricting orifice plate 72 and the shutoff valve 71 at the same time. At this time, the medium flowing through the flow-restricting orifice plate 72 and the shutoff valve 71 exceeds 75% of the load, which meets the operation requirements of the two devices.

[0054] In the embodiment of the present application, the slurry pool of the desulfurization tower device 1 is provided with a concentration monitoring sensor 11 for detecting the medium concentration, i.e., the amount of gypsum generated in the slurry pool, for representing the high or low of the gypsum production. When the detected medium concentration is greater than the preset value, the adjusting component is controlled by the adjusting controller 80 to switch to the second state. When the detected medium concentration in the slurry pool is less than or equal to the preset value, the adjusting component is controlled by the adjusting controller 80 to switch to the first state.

[0055] Thus, in combination with Figure 2 、 3 As shown in the figure, the flow adjusting device of the slurry conveying pipeline according to the embodiment of the present application utilizes the process thereof for adjusting the slurry conveying flow, which includes:

[0056] Monitoring the medium concentration in the slurry pool of the desulfurization tower device 1 to determine the amount of gypsum in the slurry in the slurry pool;

[0057] According to the monitored medium concentration, controlling the pumping from the buffer container 3 to the gypsum dewatering device and controlling the operation of the gypsum dewatering device, wherein:

[0058] In response to the monitored medium concentration in the slurry pool being greater than the preset value, the adjusting component is controlled to be in the second state, so that the shutoff valve 71 is in the open state, and the medium flowing through the second pipeline 5 flows through the flow-restricting orifice plate 72 and the shutoff valve 71 at the same time. The upper limit of the flow of the second pipeline 5 is less than or equal to the total dewatering flow of the first dewatering device and the second dewatering device. And, the first dewatering device 61 and the second dewatering device 62 are controlled to be started to perform gypsum dewatering treatment at the same time.

[0059] In response to the monitored medium concentration in the slurry pool being less than or equal to the preset value, the adjusting component is controlled to switch to the first state, and the shutoff valve 71 is controlled to switch to the shutoff state. The medium flowing through the second pipeline 5 only flows through the flow-restricting orifice plate 72, so that the upper limit of the flow of the second pipeline 5 is less than or equal to the dewatering flow of the first dewatering device or the second dewatering device. And, the first dewatering device 61 or the second dewatering device 62 is controlled to be started to perform gypsum dewatering treatment.

[0060] As described in the foregoing embodiments, in the example of the present application, whether the gypsum production reaches the 75% load standard is distinguished and controlled to switch the adjustment.

[0061] In the optional embodiment, if the power of the first dewatering device 61 or the second dewatering device 62 is different, the upper limit of the flow of the flow-limiting orifice plate 72 is less than or equal to the dewatering flow of the device with smaller power among the first dewatering device or the second dewatering device.

[0062] In the preferred embodiment, the shut-off valve 71 is a butterfly valve.

[0063] Preferably, the flow-limiting orifice plate 72 is located above the shut-off valve 71, so as to avoid the slurry blockage of the flow-limiting orifice plate 72.

[0064] In combination with the above embodiments, in the original structure, only a shut-off valve and a flow-limiting orifice plate are added on the second pipeline. When the shut-off valve of the main pipeline is closed, the working medium only flows through the flow-limiting orifice plate. Due to the throttling of the flow-limiting orifice plate, the pipeline delivery capacity meets the processing capacity of one dewatering device. The working medium flow dead zone before and after the shut-off valve is extremely short. The flow-limiting orifice plate is installed above the shut-off valve, so the slurry blockage phenomenon does not occur. The overall cost is only about 5000 yuan. The larger the slurry delivery capacity is, the more investment can be saved.

[0065] Although the present application has been disclosed with the preferred embodiments as above, it is not intended to limit the present application. Those skilled in the art without departing from the spirit and scope of the present application can make various modifications and decorations. Therefore, the protection scope of the present application shall be subject to the definition of the claims.

Claims

1. A flow regulating device for a slurry pipeline, characterized by, The method comprises the following steps: A desulfurization tower device (1) is used for desulfurization and produces gypsum in a slurry pool; A buffer container (3) is connected to the slurry pool through a first pipeline (2) and is used for transporting slurry in the slurry pool to the buffer container (3); A gypsum dewatering device is connected to the buffer container (3) through a second pipeline (5), the second pipeline (5) is provided with a delivery pump (4), and the gypsum dewatering device comprises a first dewatering device and a second dewatering device, and two branch pipes are arranged at the end of the second pipeline (5) and are connected to the first dewatering device and the second dewatering device respectively; The second pipeline (5) is provided with an adjusting component, and the adjusting component is arranged to comprise a first state and a second state, wherein: In the first state, the upper limit of the flow of the second pipeline (5) is less than or equal to the dewatering flow of the first dewatering device or the second dewatering device; In the second state, the upper limit of the flow of the second pipeline (5) is less than or equal to the total dewatering flow of the first dewatering device and the second dewatering device; The adjusting component comprises a shut-off valve (71) and a flow-limiting orifice plate (72), the shut-off valve (71) and the flow-limiting orifice plate (72) are connected to the second pipeline (5) in parallel, so that the medium in the buffer container (3) is pumped into the second pipeline (5) through the delivery pump (4) and transported to the gypsum dewatering device, and at least two flow switching control channels are formed in the second pipeline (5), one of which is controlled by the shut-off valve (71) and the other of which is controlled by the flow-limiting orifice plate (72); The flow-limiting orifice plate (72) is located above the shut-off valve (71); When the adjusting component is in the first state, the shut-off valve (71) is in a closed state, and the medium in the second pipeline (5) flows from the flow-limiting orifice plate (72); When the adjusting component is switched to the second state, the shut-off valve (71) is in an open state, and the medium in the second pipeline (5) flows from the flow-limiting orifice plate (72) and the shut-off valve (71) at the same time.

2. The flow regulating device for slurry pipeline according to claim 1, characterized in that, When the power of the first dewatering device and the second dewatering device is the same, and each dewatering device has the same maximum processing capacity, the upper limit of the flow of the flow-limiting orifice plate (72) is less than or equal to the dewatering flow of the first dewatering device or the second dewatering device.

3. A flow regulating device for a slurry pipeline according to claim 2, wherein, The shut-off valve (71) is a butterfly valve.

4. The flow regulating device for slurry pipeline of claim 1, wherein, The flow-limiting orifice plate (72) comprises a wear-resistant alloy plate and a through hole arranged at the center of the wear-resistant alloy plate.

5. The flow regulating device for slurry pipeline of claim 1, wherein, The buffer container (3) is provided with a stirrer (31) for mixing the medium in the buffer container (3).

6. The flow regulating device for slurry pipeline of claim 1, wherein, The desulfurization tower device (1) is provided with a concentration monitoring sensor (11) in the slurry pool for detecting the concentration of the medium; When the detected concentration of the medium is greater than a preset value, the adjusting component is controlled to be in the second state, and when the concentration of the medium in the slurry pool is less than or equal to the preset value, the adjusting component is controlled to be switched to the first state.

7. The method of pulp flow regulation of a flow regulating device of a pulp delivery pipe according to any one of claims 1 - 6, characterized in that, The method comprises the following steps: Monitoring the concentration of the medium in the slurry pool of the desulfurization tower device (1) to determine the amount of gypsum in the slurry in the slurry pool; According to the monitored medium concentration, the pumping from the buffer container (3) to the gypsum dewatering device is controlled, and the operation of the gypsum dewatering device is controlled, wherein: in response to the monitored medium concentration in the slurry pool being greater than a preset value, the adjusting component is controlled in the second state, so that the shutoff valve (71) is in an open state, the medium flowing in the second pipeline (5) flows through the flow limiting orifice plate (72) and the shutoff valve (71) at the same time, the upper limit of the flow of the second pipeline (5) is less than or equal to the total dewatering flow of the first dewatering device and the second dewatering device; and the first dewatering device (61) and the second dewatering device (62) are controlled to be started to perform gypsum dewatering treatment at the same time; in response to the monitored medium concentration in the slurry pool being less than or equal to a preset value, the adjusting component is controlled to switch to the first state, the shutoff valve (71) is controlled to switch to a shutoff state, and the medium flowing in the second pipeline (5) only flows through the flow limiting orifice plate (72), so that the upper limit of the flow of the second pipeline (5) is less than or equal to the dewatering flow of the first dewatering device or the second dewatering device; and the first dewatering device (61) or the second dewatering device (62) is controlled to be started to perform gypsum dewatering treatment.

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