Spray regulating valve control system of desulfurization wastewater device

Abstract

The invention relates to a spray regulating valve control system of a desulfurization wastewater device. The spray regulating valve control system comprises a first evaporator outlet temperature input module; a temperature selection control module; the temperature-based valve adjusting module is used for outputting a first valve opening instruction when the outlet temperature of the evaporator is lower than a preset temperature threshold value; a unit load input module; a first delay module; the valve opening degree selection module is used for outputting a corresponding second valve opening degree instruction according to a direct proportion relation according to the delayed unit load; the switching selection module is used for receiving the output of the temperature selection control module, the temperature-based valve adjusting module and the valve opening selection module, taking a first valve opening instruction as the output of the valve opening according to the temperature protection instruction, and taking a second valve opening instruction as the output of the valve opening according to the holding instruction; and a spray regulating valve control module and a PID control module. Compared with the prior art, the system has the advantages of being accurate in control, capable of improving efficiency, safe, stable and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of desulfurization wastewater control, and particularly relates to a spray regulating valve control system of a desulfurization wastewater device. BACKGROUND

[0002] The current desulfurization wastewater zero discharge system adopts a bypass flue gas evaporation process to treat the desulfurization wastewater, and utilizes the heat of high-temperature flue gas to treat the desulfurization wastewater, so as to realize the zero discharge of the desulfurization wastewater. One set of independent bypass flue gas evaporation tower is respectively arranged on both sides of the desulfurization steel frame.

[0003] The bypass flue gas evaporation system utilizes the high-temperature flue gas of a boiler to combine with the desulfurization wastewater liquid drops separated by a cyclone atomizer, remove the water in the wastewater liquid drops, and generate solid ash to meet the requirement of zero discharge of the wastewater treatment. The high-temperature flue gas is taken from the air preheater A / B inlet flue, and the desulfurization wastewater is taken from the spray water tank through a spray water pump. Since the temperature of the flue gas in the system is affected by the load of the unit, a spray regulating valve is arranged in the pipeline from the outlet of the spray water pump to the front of the cyclone atomizer to control the flow of the wastewater, so as to match the corresponding flue gas temperature under different loads.

[0004] The operator often ignores the flow adjustment of the spray regulating valve in the desulfurization wastewater system during the process of increasing or decreasing the load, and thus the following situations are caused.

[0005] 1) The flow of the desulfurization wastewater is low under the high-load condition, the flue gas temperature is high, and the wastewater system cannot fully release the treatment potential.

[0006] 2) The flow of the wastewater is not reduced under the low-load condition, the flue gas temperature is too low, the water in the wastewater liquid drops cannot be completely removed in the water evaporation tower, and finally enters the storage pump, causing the storage pump to be blocked and the wastewater system to be disabled, and the equipment is damaged. SUMMARY

[0007] The present application is to overcome the defects of the prior art, that is, the flow of the desulfurization wastewater is low under the high-load condition, the flue gas temperature is high, and the flow of the wastewater is not reduced under the low-load condition, and the flue gas temperature is too low, which easily causes blockage, and provides a spray regulating valve control system of a desulfurization wastewater device.

[0008] The purpose of the present application can be achieved by the following technical solutions.

[0009] A spray regulating valve control system of a desulfurization wastewater device, wherein a spray regulating valve is arranged in the desulfurization wastewater device to control the flow of the wastewater, so as to match the corresponding flue gas temperature under different loads, and the system comprises:

[0010] A first evaporator outlet temperature input module is arranged to obtain the evaporator outlet temperature.

[0011] a temperature selection control module configured to determine whether the evaporator outlet temperature is lower than a preset temperature threshold, and output a temperature protection instruction if the evaporator outlet temperature is lower than the preset temperature threshold, or output a keep instruction otherwise;

[0012] a temperature-based valve adjustment module configured to output a first valve opening degree instruction when the evaporator outlet temperature is lower than the preset temperature threshold;

[0013] a unit load input module configured to obtain a unit load;

[0014] a first delay module configured to perform delay calculation on the input value of the unit load, and output a delayed unit load;

[0015] a valve opening degree selection module configured to output a corresponding second valve opening degree instruction according to the delayed unit load in a positive proportional relationship;

[0016] a switching selection module configured to receive outputs of the temperature selection control module, the temperature-based valve adjustment module, and the valve opening degree selection module, output the first valve opening degree instruction as the valve opening degree according to the temperature protection instruction, and output the second valve opening degree instruction as the valve opening degree according to the keep instruction;

[0017] a spray adjustment valve control module configured to perform opening degree adjustment according to the valve opening degree output by the switching selection module;

[0018] a PID control module configured to perform PID control on the valve opening degree of the spray adjustment valve control module.

[0019] Further, the system further comprises:

[0020] a biasing module configured to apply a biasing amount;

[0021] a valve opening degree biasing module configured to determine a final biasing amount after range limiting the biasing amount;

[0022] a first accumulation module configured to add the second valve opening degree instruction and the final biasing amount to obtain a new second valve opening degree instruction, and input the new second valve opening degree instruction to the switching selection module.

[0023] Further, the range limiting is limiting the biasing amount within a range of ±10.

[0024] Further, the system further comprises:

[0025] a second evaporator outlet temperature input module configured to obtain an evaporator outlet temperature;

[0026] a second delay module configured to perform delay calculation on the evaporator outlet temperature, and output a delayed evaporator outlet temperature;

[0027] a second accumulation module, configured to determine a final evaporator outlet temperature by adding the delayed evaporator outlet temperature and the final biasing amount;

[0028] The PID control module further performs feedback adjustment of PID control based on the final evaporator outlet temperature.

[0029] Further, the system further comprises:

[0030] a manual-automatic switching module connected in series between the switching selection module and the spray adjustment valve control module, and further receiving a manual valve control instruction, configured to transmit the manual valve control instruction or the valve opening degree output by the switching selection module according to the instruction of the spray adjustment valve control module.

[0031] Further, the temperature threshold is within the range of 190-210 degrees Celsius.

[0032] Further, the valve opening degree selection module matches and outputs a corresponding second valve opening degree instruction according to different unit load intervals, and the second valve opening degree instruction is in a positive proportional relationship with the unit load interval.

[0033] Further, the spray adjustment valve control module further receives a spray adjustment valve opening degree feedback, configured to determine a deviation amount by comparing the valve opening degree instruction, and input the deviation amount into the PID control module to obtain a valve opening degree adjustment result.

[0034] Further, the spray adjustment valve is installed before a cyclone atomizer at an outlet pipeline of a spray water pump in a desulfurization wastewater device.

[0035] Further, when the spray adjustment valve control module controls the valve opening degree output when the evaporator outlet temperature is lower than the temperature threshold, the opening degree of the spray adjustment valve is first closed to 0%, and then adjusted to the valve opening degree.

[0036] Compared with the prior art, the present application has the following advantages:

[0037] (1) In one aspect, the present application realizes automatic matching of the flue gas temperature corresponding to different unit loads by selecting the valve opening degree according to the size of the unit load through the valve opening degree selection module in a positive proportional relationship. In another aspect, the valve is provided with a low smoke temperature protection. The evaporator outlet temperature is acquired in real time, and if it is lower than the temperature threshold, the valve opening degree generated based on the excessively low smoke temperature is taken as the final valve opening degree control instruction through the switching selection module, so as to maintain a high valve opening degree and avoid the problem of silo pump blockage caused by excessively low smoke temperature.

[0038] On this basis, the obtained unit load increase delay timer is also calculated, so as to avoid the excessive adjustment of the valve opening degree caused by the short and severe fluctuation of the unit load, and to affect the stability of the system.

[0039] Overall, the wastewater treatment capacity of the desulfurization wastewater device is greatly improved, and it is more stable and reliable.

[0040] (2) The present application takes into account that the wastewater consistency at the end of the desulfurization wastewater device is too high, and in the valve opening degree adjustment process, there is a dead zone of control, i.e. a hollow layer, and the trace valve opening degree cannot affect the wastewater flow; for this, a bias module is added to form a valve opening degree bias superimposed on the valve opening degree determined by the unit load, to realize more reliable flow adjustment.

[0041] (3) Precise control: according to the specific load, the wastewater flow can be precisely adjusted, so that the wastewater treatment process is more uniform, and the excessive or insufficient flow is effectively avoided.

[0042] (4) Improve efficiency: it can quickly respond to changes in unit load, and when the load suddenly rises or falls, the spray regulating valve can quickly adjust the opening degree, so that the system reaches the ideal state in the first time.

[0043] (5) Increase safety: automatic adjustment of wastewater flow, and low temperature protection of smoke can effectively protect the warehouse pump at the outlet of the evaporation tower from being blocked, and thus make the equipment safe and stable operation.

[0044] (6) Stabilize the system: it helps to maintain the stability of the desulfurization wastewater system, and reduces the fluctuation caused by manual operation delay or inaccuracy. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 A flowchart of a spray regulating valve control system of a desulfurization wastewater device provided in the embodiment of the present application is shown;

[0046] Figure 2 A logic diagram of a spray regulating valve control system of a desulfurization wastewater device provided in the embodiment of the present application is shown. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0048] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0049] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0050] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limiting the present invention.

[0051] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0052] Furthermore, terms such as "horizontal" and "vertical" do not necessarily mean that a component must be absolutely horizontal or overhanging, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather that it can be slightly tilted.

[0053] Example 1

[0054] like Figure 1 and Figure 2 As shown, this embodiment provides a spray regulating valve control system for a desulfurization wastewater device. The desulfurization wastewater device is provided with a spray regulating valve, which is installed in the desulfurization wastewater device between the spray water pump outlet pipe and the cyclone atomizer to control the wastewater flow rate to match the flue gas temperature corresponding to different loads. The system includes:

[0055] A first evaporator outlet temperature input module HAI42 is used to obtain the evaporator outlet temperature;

[0056] A temperature selection control module CMP43 is configured to determine whether the evaporator outlet temperature is lower than a preset temperature threshold, and output a temperature protection instruction if yes, or output a maintaining instruction if no.

[0057] A temperature-based valve adjustment module FX44 is configured to output a first valve opening degree instruction when the evaporator outlet temperature is lower than the preset temperature threshold.

[0058] A unit load input module PAI29 is configured to obtain the unit load.

[0059] A first delay module LDLG39 is configured to output a delayed unit load after performing delay calculation on the input value of the unit load.

[0060] A valve opening degree selection module FX30 is configured to output a corresponding second valve opening degree instruction according to the delayed unit load in a positive proportional relationship.

[0061] A switching selection module ASEL46 is configured to receive the outputs of the temperature selection control module, the temperature-based valve adjustment module and the valve opening degree selection module, and output the first valve opening degree instruction as the valve opening degree according to the temperature protection instruction, or output the second valve opening degree instruction as the valve opening degree according to the maintaining instruction.

[0062] A spray adjustment valve control module MA14 is configured to perform opening degree adjustment according to the valve opening degree output by the switching selection module.

[0063] A PID control module PID13 is configured to perform PID control on the valve opening degree of the spray adjustment valve control module.

[0064] In one aspect, the size of the unit load is obtained in real time, and the valve opening degree is selected according to the size of the unit load by the valve opening degree selection module in a positive proportional relationship, so as to realize automatic matching of the flue gas temperature corresponding to different unit loads. In another aspect, the flue gas temperature low protection is set for the valve, the evaporator outlet temperature is obtained in real time, and it is determined that if the evaporator outlet temperature is lower than the temperature threshold, the valve opening degree generated based on the too low flue gas temperature is output as the final valve opening degree control instruction by the switching selection module, so as to maintain a high valve opening degree and avoid the problem of the warehouse pump blockage caused by the too low flue gas temperature.

[0065] On this basis, the obtained unit load is calculated by a time delay device, so as to avoid excessive adjustment of the valve opening degree caused by temporary and severe fluctuations of the unit load, and affect the stability of the system.

[0066] Overall, the wastewater treatment capacity of the desulfurization wastewater device is greatly improved, and is more stable and reliable.

[0067] The temperature threshold is within the range of 190-210 degrees Celsius, and is preferably 200 degrees Celsius or 205 degrees Celsius.

[0068] In this embodiment, the temperature selection control module CMP43 outputs a temperature protection instruction value of 1 when the temperature is below the temperature threshold value, and outputs a holding instruction value of 0 when the temperature is above the temperature threshold value.

[0069] The setting end SEL of the switching selection module ASEL46 selects the output X1 of the temperature-based valve adjustment module FX44 as the final output when the temperature protection instruction value of 1 is received, and selects the output X2 of the valve opening selection module FX30 as the final output when the holding instruction value of 0 is received.

[0070] The valve opening selection module FX30 matches the output corresponding to the second valve opening instruction according to different unit load intervals, and the second valve opening instruction is in a positive proportional relationship with the unit load interval.

[0071] Preferably, the system further comprises:

[0072] The biasing module ACON38 is used to apply a biasing amount.

[0073] The valve opening biasing module VSET5 is used to determine a final biasing amount after range limiting according to the biasing amount.

[0074] The first accumulation module ADD35 is used to add the second valve opening instruction and the final biasing amount to obtain a new second valve opening instruction input to the switching selection module.

[0075] The present application considers that the wastewater thickness at the end of the desulfurization wastewater device is too high, and there is a control dead zone, i.e., a control hollow layer, in the valve opening adjustment process, and the trace valve opening adjustment cannot affect the wastewater flow. To this end, a biasing module is added to form a valve opening biasing superposition to the valve opening determined by the unit load, so as to realize more reliable flow adjustment.

[0076] The range limiting is to limit the biasing amount within the range of ±10.

[0077] Preferably, the system further comprises:

[0078] The second evaporator outlet temperature input module HAI21 is used to obtain the evaporator outlet temperature.

[0079] The second delay module LDLG1 is used to output the delayed evaporator outlet temperature after delay calculation on the evaporator outlet temperature.

[0080] The second accumulation module ADD6 is used to determine the final evaporator outlet temperature after adding the delayed evaporator outlet temperature and the final biasing amount.

[0081] The PID control module also performs feedback adjustment of PID control based on the final evaporator outlet temperature to determine whether effective flue gas temperature adjustment is achieved in the control process of the valve opening.

[0082] Preferably, the system further comprises:

[0083] The hand-automatic switching module ASEL34 is connected in series between the switching selection module and the spray adjustment valve control module, and also receives a manual valve control instruction, which is used to transmit the manual valve control instruction or the valve opening output by the switching selection module according to the instruction of the spray adjustment valve control module.

[0084] The hand-automatic switching module ASEL34 also receives a spray adjustment valve opening given amount to set the valve opening corresponding to the manual valve control instruction.

[0085] Preferably, the spray adjustment valve control module also receives a spray adjustment valve opening feedback, which is used to determine a deviation amount by comparison with the valve opening instruction and input into the PID control module to obtain a valve opening adjustment result.

[0086] Preferably, when the spray adjustment valve control module controls the valve opening output by the evaporator outlet temperature being lower than the temperature threshold value, the opening of the spray adjustment valve is first closed to 0%, and then adjusted to the valve opening to reach the opening corresponding to the minimum flow.

[0087] For example, when the flue gas temperature at the outlet of the wastewater evaporation tower is lower than 200℃, the spray adjustment valve is automatically closed to 0% and then opened to 16%.

[0088] The preferred embodiments of the present application are described in detail above. It should be understood that those skilled in the art can make many modifications and changes to the present application without creative labor based on the concept of the present application. Therefore, any technical solution obtained by logical analysis, reasoning or limited experiment based on the prior art according to the concept of the present application shall be within the protection scope defined by the claims.

Claims

1. A spray regulating valve control system for a desulfurization wastewater device, wherein the desulfurization wastewater device is provided with a spray regulating valve for controlling the wastewater flow rate to match the flue gas temperature at different loads, characterized in that: The system comprises: A first evaporator outlet temperature input module, used to obtain the evaporator outlet temperature; The temperature selection control module is used to determine whether the evaporator outlet temperature is lower than a preset temperature threshold. If so, it outputs a temperature protection instruction; otherwise, it outputs a hold instruction. A temperature-based valve adjustment module, configured to output a first valve opening instruction when the evaporator outlet temperature is lower than a preset temperature threshold; Unit load input module, used to obtain unit load; The first delay module is used to perform delay calculation on the input value of the unit load and output the delayed unit load; The valve opening selection module is used to output the corresponding second valve opening instruction in direct proportion to the delayed unit load; a switching selection module, configured to receive outputs from the temperature selection control module, the temperature-based valve adjustment module, and the valve opening selection module, and output the first valve opening instruction as the valve opening according to the temperature protection instruction, and output the second valve opening instruction as the valve opening according to the hold instruction; The spray regulating valve control module is used to adjust the valve opening according to the valve opening output by the switching selection module; The PID control module is used to perform PID control on the valve opening of the spray regulating valve control module.

2. The spray regulating valve control system of a desulfurization wastewater device according to claim 1, characterized in that: The system further comprises: A bias module, used for applying a bias amount; A valve opening offset module, configured to determine a final offset after performing range limiting according to the offset; The first accumulating module is configured to add the second valve opening instruction and the final offset to obtain a new second valve opening instruction and input the new instruction to the switching selecting module.

3. The spray regulating valve control system of a desulfurization wastewater device according to claim 2 is characterized in that: The range is limited to limit the offset to within the range of ±10.

4. The spray regulating valve control system of a desulfurization wastewater device according to claim 2, characterized in that: The system further comprises: A second evaporator outlet temperature input module is used to obtain the evaporator outlet temperature; The second delay module is used to perform a delay calculation on the evaporator outlet temperature and output the delayed evaporator outlet temperature; a second accumulating module, configured to add the delayed evaporator outlet temperature and the final offset to determine a final evaporator outlet temperature; The PID control module further performs feedback adjustment of PID control based on the final evaporator outlet temperature.

5. The spray regulating valve control system of a desulfurization wastewater device according to claim 1, characterized in that: The system further comprises: The manual-automatic switching module is connected in series between the switching selection module and the spray regulating valve control module, and also receives manual valve control instructions. It is used to transmit manual valve control instructions or valve opening output by the switching selection module according to the instructions of the spray regulating valve control module.

6. The spray regulating valve control system of a desulfurization wastewater device according to claim 1, characterized in that: The temperature threshold is within the range of 190-210 degrees Celsius.

7. The spray regulating valve control system of a desulfurization wastewater device according to claim 1, characterized in that: The valve opening selection module matches and outputs a corresponding second valve opening instruction according to different unit load intervals, and the second valve opening instruction is in direct proportion to the unit load interval.

8. The spray regulating valve control system of a desulfurization wastewater device according to claim 1, characterized in that: The spray regulating valve control module also receives spray regulating valve opening feedback, which is used to compare with the valve opening instruction to determine the deviation, and input it into the PID control module to obtain the valve opening adjustment result.

9. The spray regulating valve control system of a desulfurization wastewater device according to claim 1, characterized in that: The spray regulating valve is installed in the desulfurization wastewater device between the spray water pump outlet pipe and the cyclone atomizer.

10. The spray regulating valve control system of a desulfurization wastewater device according to claim 1, characterized in that: When the evaporator outlet temperature is lower than the temperature threshold, the spray regulating valve control module first closes the spray regulating valve opening to 0% and then adjusts it to the valve opening.

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