A coke oven high-pressure ammonia water system stable operation control method

Abstract

The application relates to a stable operation control method of a coke oven high-pressure ammonia water system, and relates to the technical field of coke oven production. When the coke oven production load is low, the valves on a plurality of high-pressure ammonia water branch pipes used for pipeline flushing are opened, so that the high-pressure ammonia water still has a flow rate of 5-40 m 3 / h when no coal is loaded; the set pressure of the high-pressure ammonia water pump in the standby state is reduced to 0.8-1.8 MPa, the frequency converter frequency of the high-pressure ammonia water pump motor is reduced, the rotating speed of the impeller is reduced, and the heat generated by the ammonia water and the impeller friction is reduced. The coke oven high-pressure ammonia water system stable operation control method has the advantages that the operation is simple, the effect is remarkable, the production operation control method is changed without increasing investment cost and equipment, the system operation pressure is stabilized, the influence of the sharp fluctuation of the high-pressure ammonia water pressure on production is prevented, and a safety production accident such as equipment damage is avoided.

Description

Technical Field

[0001] This invention relates to the field of coke oven production technology, and specifically to a method for stable operation control of a high-pressure ammonia water system in a coke oven. Background Technology

[0002] To meet environmental protection requirements, most domestic coking plants have adopted high-pressure ammonia water smokeless coal charging technology. This involves opening the high-pressure ammonia water valve during coal charging in the coke oven carbonization chamber, introducing high-pressure ammonia water at approximately 2.3 MPa into the coke oven bridge pipe. The negative pressure generated by the high-speed jet of ammonia water from nozzles installed inside the bridge pipe draws the smoke and dust produced by the coal entering the carbonization chamber and encountering high temperatures into the gas collecting pipe, thus preventing smoke from escaping from the furnace door or charging port, achieving the environmentally friendly effect of smokeless coal charging.

[0003] Currently, the control method for high-pressure ammonia water systems in domestic coke ovens is generally as follows: Normally, the high-pressure ammonia water pump maintains a constant pressure. When a specific furnace's carbonization chamber is ready for coal loading, the valve on the high-pressure ammonia water pipe is opened, injecting high-pressure ammonia water into the gas bridge pipe. This control method has certain problems in the early stages of coke oven production or when production load is low due to factors such as reduced production: Because the high-pressure ammonia water is only intermittently used during coal loading, and stops flowing when not loading coal, the impeller of the high-pressure ammonia water pump continues to rotate at high speed. The heat generated by the friction between the impeller and the stopped ammonia water cannot be carried away by the flowing ammonia water, causing the ammonia water temperature inside the pump to gradually rise. When the coke oven is operating at low load, the coal loading interval is extended, and the time when the ammonia water stops flowing is correspondingly longer. The time for the ammonia water inside the pump to heat up due to friction with the impeller is also extended, and the temperature rises even higher. When the ammonia water reaches a sufficient temperature, it will vaporize in large quantities, filling the pump with a large amount of gas, causing vapor binding. This leads to significant fluctuations in the outlet pipeline pressure, significantly impacting the stable operation of the high-pressure ammonia water system. In severe cases, the alternating flow of gas and liquid produced by the vaporization of ammonia water can also generate a water hammer effect, causing huge impacts on pipelines and water pumps, which can lead to pipeline damage or water pump failure, endangering safe production. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings and defects of the existing technology by providing a stable operation control method for a high-pressure ammonia water system in a coke oven. This stable operation control method for a high-pressure ammonia water system in a coke oven is simple to operate and has significant effects. Without increasing investment costs or adding equipment, it only changes the production operation control method to achieve the purpose of stabilizing the system operating pressure, preventing drastic fluctuations in high-pressure ammonia water pressure from affecting production, and avoiding safety production accidents caused by equipment damage.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a method for stable operation control of a high-pressure ammonia water system in a coke oven. Specifically, during the initial stage of coke oven production or when production load is low due to production reduction, valves on several high-pressure ammonia water branch pipes used for flushing the negative pressure gas pipeline are opened and kept partially open. A portion of the high-pressure ammonia water enters the negative pressure gas pipeline through the flushing pipes, ensuring a certain flow rate of high-pressure ammonia water even when no coal is being loaded. Using the high-pressure ammonia water operation control system, the set control pressure of the high-pressure ammonia water pump in standby mode (i.e., when the coke oven is not loading coal) is reduced to a certain value, thereby reducing the frequency control frequency of the high-pressure ammonia water pump motor's inverter, which in turn reduces the rotational speed of the high-pressure ammonia water pump impeller in standby mode, thus reducing the heat generated by friction between the ammonia water and the impeller.

[0006] More specifically, the following are the implementation steps for the following method: When the coke oven is in its initial production phase or when production load is low due to production reduction, the valves on several high-pressure ammonia branch pipes used for flushing the negative pressure gas pipeline are opened and kept partially open. A portion of the high-pressure ammonia water flows through the flushing pipes into the negative pressure gas pipeline, ensuring a certain flow rate of high-pressure ammonia water even when no coal is being loaded: Step 1: When the coking workshop receives a plan to reduce production load, the riser operator goes to the coke oven negative pressure gas pipeline and operates the valves on the high-pressure ammonia branch pipes used for flushing the negative pressure gas pipeline, opening one of the valves to 1 / 3 of its capacity. Step 2: The gas purification workshop operator checks the high-pressure ammonia water flow meter: if the high-pressure ammonia water flow rate is 5-40 m³ / h in standby mode... 3 If the pressure is within the specified range ( / h), proceed to step three; otherwise, return to step one, where the riser operator operates the valve on another high-pressure ammonia branch pipeline used for flushing the negative pressure gas pipeline, opening it to 1 / 3. Step three: Gas purification workshop operators observe the pressure of the high-pressure ammonia pump outlet pipeline. Under reduced coke oven production load, does the outlet pressure of the high-pressure ammonia pump fluctuate significantly over a certain period of time? If so, return to step one and continue the adjustment operation; if not, the procedure is complete, achieving the desired effect.

[0007] More specifically, the implementation steps of the high-pressure ammonia water operation control system, which reduces the set control pressure of the high-pressure ammonia water pump in standby mode to a certain value, thereby reducing the frequency control frequency of the high-pressure ammonia water pump motor and thus reducing the rotation speed of the high-pressure ammonia water pump impeller in standby mode and reducing the heat generated by friction between ammonia water and the impeller, are as follows: Step 1: When the coking workshop receives a plan to reduce production load, the gas purification workshop operator opens the high-pressure ammonia water system operation screen on the DCS operation control system computer in the central control room and adjusts the set control pressure of the high-pressure ammonia water system in standby mode to a decrease of 0.1 MPa. Step 2: The gas purification workshop operator observes the pressure of the high-pressure ammonia water pump outlet pipeline. Under the condition of reduced coke oven production load, does the outlet pressure of the high-pressure ammonia water pump fluctuate significantly within a certain period of time? If so, return to step 1 and continue the adjustment operation; if not, the implementation steps are complete, achieving the desired effect.

[0008] More specifically, the high-pressure ammonia pump is in standby mode, which is the state when the coke oven is not loading coal.

[0009] More specifically, in step two, the high-pressure ammonia water operation control system is used to reduce the set control pressure of the high-pressure ammonia water pump in standby mode to 0.8-1.8 MPa, thereby reducing the frequency control frequency of the high-pressure ammonia water pump motor's inverter.

[0010] More specifically, the gas purification workshop operators should observe the pressure of the high-pressure ammonia pump outlet pipeline. Under the condition of reduced coke oven production load, they should observe whether the outlet pressure of the high-pressure ammonia pump fluctuates significantly within a certain period of time, which is 4-8 hours.

[0011] More specifically, the operators in the gas purification workshop should carefully observe the pressure of the high-pressure ammonia pump outlet pipeline. Under conditions of reduced coke oven production load, they should observe whether the outlet pressure of the high-pressure ammonia pump experiences significant fluctuations within a certain time period, which is 4-8 hours.

[0012] After adopting the above technical solution, the beneficial effects of the present invention are as follows:

[0013] 1. When the coke oven production load is low, the valves on several branch pipelines used for pipeline flushing with high-pressure ammonia water are kept partially open to maintain a certain flow rate of high-pressure ammonia water. The small amount of flowing high-pressure ammonia water carries away the heat generated by the friction between the impeller and the ammonia water in the pump body, thereby preventing the ammonia water in the pump body from overheating and causing the temperature to rise continuously.

[0014] 2. By reducing the control pressure of the high-pressure ammonia pump in standby mode, the frequency of the inverter control of the high-pressure ammonia pump motor is reduced, thereby reducing the rotation speed of the high-pressure ammonia pump impeller. This reduces the heat generated by the friction between the ammonia and the impeller in standby mode, allowing the heat naturally dissipated into the air through the pump body to reach a new balance with the heat generated by friction, preventing the continuous accumulation of frictional heat in the pump body that would cause the temperature of the ammonia to rise continuously.

[0015] 3. It can prevent the ammonia water in the high-pressure ammonia water pump from vaporizing due to heat generated by friction, thus avoiding vapor binding within the pump. This keeps the outlet pressure of the high-pressure ammonia water pump stable, preventing large pressure fluctuations and water hammer effects on the high-pressure ammonia water pipeline and pump, as well as the resulting pipeline rupture and equipment damage. This ensures the safe and stable operation of the high-pressure ammonia water system, providing significant safety benefits. It also has a good effect on stabilizing normal coke oven production when maintaining low-load operation. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of the present invention. Detailed Implementation

[0018] See Figure 1 As shown, the technical solution adopted in this specific embodiment is:

[0019] 1. During the initial stage of coke oven production or when production load is low due to factors such as reduced production, the valves on several high-pressure ammonia branch pipes used for flushing the negative pressure gas pipeline are opened and kept partially open. A portion of the high-pressure ammonia water flows through the flushing pipes into the negative pressure gas pipeline, maintaining a certain flow rate even when no coal is being loaded. This small flow of ammonia water carries away the heat generated by the friction between the high-speed rotating impeller and the ammonia water in the high-pressure ammonia water pump. The specific implementation steps are as follows:

[0020] Step 1: When the coking workshop receives a plan to reduce the production load, the riser operator goes to the coke oven negative pressure gas pipeline and operates the valve on the high-pressure ammonia water branch pipeline used to flush the negative pressure gas pipeline, so that the valve on one of the high-pressure ammonia water branch pipelines is opened to 1 / 3.

[0021] Step 2: Operators in the gas purification workshop check the high-pressure ammonia water flow meter.

[0022] If the high-pressure ammonia flow rate is 5-40 m³ / h in standby mode 3 If the range is / h, proceed to step three;

[0023] Otherwise, return to step one, and have the riser operate the valve on another high-pressure ammonia branch pipe used to flush the negative pressure gas pipeline, opening it to 1 / 3.

[0024] Step 3: Operators in the gas purification workshop should carefully observe the pressure of the high-pressure ammonia pump outlet pipeline. Under conditions of reduced coke oven production load, should the outlet pressure of the high-pressure ammonia pump fluctuate significantly within 4-8 hours?

[0025] If so, return to step one and continue with the adjustment process;

[0026] If not, then the implementation steps are complete and the desired effect is achieved.

[0027] 2. Utilizing the high-pressure ammonia water operation control system, the set control pressure of the high-pressure ammonia water pump in standby mode (i.e., when the coke oven is not charging coal) is reduced to 0.8-1.8 MPa. This lowers the frequency control frequency of the high-pressure ammonia water pump motor's inverter, thereby reducing the rotational speed of the high-pressure ammonia water pump impeller in standby mode. This reduces the heat generated by friction between the ammonia water and the impeller, slows down the temperature rise rate of the ammonia water inside the high-pressure ammonia water pump, and prolongs the time it takes for the ammonia water to reach its vaporization temperature. The specific implementation steps are as follows:

[0028] Step 1: When the coking workshop receives a plan to reduce the production load, the gas purification workshop operators open the high-pressure ammonia water system operation screen on the DCS operation control system computer in the central control room and adjust the control pressure setpoint of the high-pressure ammonia water system in standby mode to be reduced by 0.1MPa.

[0029] Step 2: Operators in the gas purification workshop should carefully observe the pressure in the outlet pipeline of the high-pressure ammonia pump. Under reduced coke oven production load, observe whether the outlet pressure of the high-pressure ammonia pump fluctuates significantly within 4-8 hours.

[0030] If so, return to step one and continue with the adjustment process;

[0031] If not, then the implementation steps are complete and the desired effect is achieved.

[0032] The above description is only used to illustrate the technical solution of the present invention and is not intended to limit it. Any other modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention, as long as they do not depart from the spirit and scope of the technical solution of the present invention, should be covered within the scope of the claims of the present invention.

Claims

1. A method for stable operation control of a high-pressure ammonia water system in a coke oven, characterized in that: The specific plan is as follows: 1) In the early stage of coke oven production or when the production load is low due to production reduction, the valves on several high-pressure ammonia branch pipes used for pipeline flushing are opened and kept partially open. A portion of the high-pressure ammonia water enters the negative pressure gas pipeline through the flushing pipe, so that the high-pressure ammonia water still maintains a certain flow rate when no coal is loaded. 2) By using the high-pressure ammonia water operation control system, the set control pressure of the high-pressure ammonia water pump in standby mode is reduced to a certain value, thereby reducing the frequency control frequency of the high-pressure ammonia water pump motor inverter, thus reducing the rotation speed of the high-pressure ammonia water pump impeller in standby mode and reducing the heat generated by friction between ammonia water and impeller. The specific implementation steps of step 1) are as follows: Step 1: When the coking workshop receives a plan to reduce the production load, the riser operator goes to the coke oven negative pressure gas pipe and operates the valve on the high-pressure ammonia water branch pipe used to flush the negative pressure gas pipe, so that the valve on one of the high-pressure ammonia water branch pipes is opened to 1 / 3. Step 2: Operators in the gas purification workshop check the high-pressure ammonia water flow meter. If the high-pressure ammonia water flow rate is in the range of 5-40 m³ / h in standby mode, proceed to step three; Otherwise, return to step one, and have the riser operate the valve on another high-pressure ammonia branch pipe used to flush the negative pressure gas pipeline, opening it to 1 / 3. Step 3: Operators in the gas purification workshop should carefully observe the pressure of the high-pressure ammonia pump outlet pipeline. Under conditions of reduced coke oven production load, should they monitor whether the high-pressure ammonia pump outlet pressure fluctuates significantly over a certain period of time? If yes, return to step one and continue with the adjustment; if no, the steps are complete and the desired effect has been achieved. In step 2), the high-pressure ammonia water operation control system is used to reduce the set control pressure of the high-pressure ammonia water pump in standby mode to 0.8-1.8MPa, thereby reducing the frequency control frequency of the high-pressure ammonia water pump motor inverter.

2. The method for stable operation control of a high-pressure ammonia water system in a coke oven according to claim 1, characterized in that: The specific implementation steps of step 2) are as follows: Step 1: When the coking workshop receives a plan to reduce the production load, the gas purification workshop operators open the high-pressure ammonia water system operation screen on the DCS operation control system computer in the central control room and adjust the control pressure set value of the high-pressure ammonia water system in standby mode to be reduced by 0.1MPa. Step 2: Operators in the gas purification workshop should carefully observe the pressure of the high-pressure ammonia pump outlet pipeline. Under conditions of reduced coke oven production load, should they monitor whether the high-pressure ammonia pump outlet pressure fluctuates significantly over a certain period of time? If so, return to step one and continue with the adjustment process; If not, then the implementation steps are complete and the desired effect is achieved.

3. The method for stable operation control of a high-pressure ammonia water system in a coke oven according to claim 1, characterized in that: In step 2), the high-pressure ammonia pump is in standby mode, which is the state when the coke oven is not loading coal.

4. The method for stable operation control of a high-pressure ammonia water system in a coke oven according to claim 1, characterized in that: Operators in the gas purification workshop should pay attention to the pressure of the high-pressure ammonia pump outlet pipeline. Under the condition of reduced coke oven production load, they should observe whether the outlet pressure of the high-pressure ammonia pump fluctuates significantly within a certain period of time, which is 4-8 hours.

5. The method for stable operation control of a high-pressure ammonia water system in a coke oven according to claim 2, characterized in that: Operators in the gas purification workshop should pay attention to the pressure of the high-pressure ammonia pump outlet pipeline. Under the condition of reduced coke oven production load, they should observe whether the outlet pressure of the high-pressure ammonia pump fluctuates significantly within a certain period of time, which is 4-8 hours.

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