Water seal optimization energy-saving method for heating furnace of hot-rolled plate factory

Abstract

The invention relates to the technical field of water seal energy-saving optimization, in particular to a hot-rolled plate factory heating furnace water seal energy-saving optimization method which comprises the following steps: taps are tapped from a heating furnace clean circulating water return pipeline and are connected to a water seal tank water replenishing pipeline; a middle branch pipe of a water supplementing pipeline of the water seal tank is tapped and is in butt joint communication with a pipeline through which clean circulating water passes, and water supplementing for all the water seal tanks is realized by communicating one branch pipe according to the characteristic that five water seal tanks are mutually communicated through pipelines; in the shutdown maintenance period, a valve between the clean circulating water and the water seal tank is opened, a valve of an original water supplementing branch pipe of the water seal tank is closed, water is supplemented to the water seal tank through the clean circulating water, meanwhile, operation of a water treatment water pump is stopped, and the energy-saving purpose is achieved. The problems that an existing water treatment system needs a 450KW pump for continuous operation to keep the water level, energy consumption is large, and a valve needs to be closed frequently are solved.

Description

Technical Field

[0001] This invention relates to the field of water seal energy-saving optimization technology, specifically to a method for optimizing and saving energy in the water seal of a heating furnace in a hot rolling mill. Background Technology

[0002] The circulating water in the hot-rolled plate plant is mainly used for cooling equipment during production and for replenishing the water seal tank of the heating furnace;

[0003] During shutdown and maintenance, the equipment is in a shutdown state and does not require cooling. Moreover, the heating furnace is in a standby state during maintenance, and the water evaporation in the water seal tank is minimal, requiring a small amount of circulating water. However, in order to ensure the water level in the heating furnace water seal tank, the water treatment system must ensure the operation of a 450KW pump, which is a significant energy consumption. Furthermore, each shutdown requires the operation of numerous valves to shut off the water. Summary of the Invention

[0004] The technical problem to be solved by this invention is that existing water treatment systems require a 450KW pump to run continuously in order to maintain the water level, which consumes a lot of energy and requires frequent valve closures.

[0005] To solve the above problems, the technical solution adopted in this invention is a method for optimizing the water seal of a heating furnace in a hot-rolled plate plant to save energy, comprising the following steps:

[0006] Draw a tap in the return water pipe of the heating furnace and connect it to the water seal tank replenishment pipe;

[0007] Draw a tap on the middle branch pipe of the water seal tank replenishment pipe and connect it to the pipe coming from the clean circulation water. Taking advantage of the fact that the five water seal tanks are interconnected through pipes, water can be replenished to all water seal tanks by connecting a branch pipe.

[0008] During shutdown and maintenance, open the valve between the clean circulating water and the water seal tank, close the valve of the original water supply branch pipe of the water seal tank, replenish the water seal tank with clean circulating water, and at the same time stop the operation of the water treatment pump to achieve energy saving.

[0009] As a further aspect of the present invention: when tapping the return water pipe of the heating furnace, a part of the return water pipe with stable pressure and water quality that meets the water supply requirements of the water seal tank is selected for tapping, so as to ensure that the water connected to the water supply pipe of the water seal tank can meet the normal operation requirements of the water seal tank and will not cause damage to the equipment in the water seal tank.

[0010] As a further aspect of the present invention: when connecting the pipe to the water seal tank replenishment pipe, the pipe is a DN50 pipe. The pipe diameter is determined comprehensively based on the minimum water replenishment required by the water seal tank during shutdown maintenance and the pressure, flow rate and other parameters of the net circulating water return pipe, so as to ensure that the water seal tank can be replenished stably and effectively during shutdown maintenance.

[0011] As a further aspect of the present invention: when a tap is made on the middle branch pipe of the water seal tank replenishment pipe and connected to the pipe from the clean circulating water, a flange connection structure is set at the connection point to facilitate subsequent pipe inspection, maintenance and replacement, while ensuring the sealing of the connection point to prevent water leakage from affecting the water replenishment effect.

[0012] As a further aspect of the present invention: after opening the valve between the clean circulating water and the water seal tank during shutdown and maintenance, the water level change in the water seal tank is monitored in real time, and the valve opening is adjusted in a timely manner according to the water level change to ensure that the water level in the water seal tank is always kept within a safe and stable range, so as to avoid overflow due to excessively high water level or excessively low water level affecting the normal operation of the heating furnace.

[0013] As a further aspect of the present invention: After this improvement, 450 kWh of electricity can be saved per hour during shutdown maintenance. This energy-saving data is based on the actual production and operation of the 1580 line of the Lianggong hot rolling mill. It is calculated by comparing the running time and power consumption of the water treatment pumps during shutdown maintenance before and after the improvement, providing a quantitative basis for evaluating the improvement effect.

[0014] As a further aspect of the present invention: the method is applied to the existing pipeline system of the 1580 line of the hot rolling mill of Lianggong Steel. Without changing the overall layout of the original turbid circulating water for cooling equipment and turbid circulating water for heating furnace water seal tank in the same water supply pipeline, energy-saving improvement is achieved only by tapping from the return water pipeline of the heating furnace clean circulating water and connecting it to the water supply pipeline of the water seal tank.

[0015] Compared with the prior art, the advantages of this invention are as follows: By tapping from the return water pipe of the heating furnace to the water supply pipe of the water seal tank, the supply of turbid circulating water can be directly stopped during shutdown and maintenance, and the water volume of the water seal tank can be guaranteed by using the clean circulating water. This solves the problem of energy waste in the prior art simply and efficiently without changing the overall layout of the original pipe network, reduces the complexity of operation, and ensures the normal operation of the heating furnace by real-time monitoring and adjustment of the water level. Furthermore, the significant energy-saving effect has been verified by actual data. Attached Figure Description

[0016] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0017] Figure 1 This is a schematic diagram of an improved energy-saving method for optimizing the water seal of a heating furnace in a hot-rolled plate plant according to the present invention.

[0018] Figure 2 This is a schematic diagram of the design principle of the turbid circulating water in the heating furnace of a hot rolling mill heating furnace according to the present invention.

[0019] Figure 3 This is a schematic diagram of the net circulating water design principle of the heating furnace in the energy-saving method for optimizing the water seal of the heating furnace in a hot-rolled plate plant according to the present invention. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] This invention provides a technical solution to address the existing problems mentioned in the background section.

[0022] Combined with appendix Figure 1-3 It can be seen that the first step is to conduct an on-site survey of the return water pipe and the water seal trough replenishment pipe of the heating furnace of the 1580 line of the hot rolling plate plant of Lianggong Steel. The specific location on the return water pipe with stable pressure and water quality that meets the requirements of the water seal trough replenishment is determined as the tap point. At the same time, the size of the intermediate branch pipe of the water seal trough replenishment pipe is measured to determine the subsequent operation position.

[0023] Next, the pipeline is installed. A flat end is cut at the selected tap location of the clean loop water return pipe using a cutting tool. A suitable flange is installed, ensuring it is concentric with the pipe and securely fixed. If welding is used, the welding quality must be flawless. A DN50 pipe is selected. This pipe diameter is determined based on the minimum water replenishment required during the water seal tank's shutdown and maintenance, as well as the pressure and flow rate of the clean loop water return pipe. One end is connected to the flange on the clean loop water return pipe using bolts, nuts, and gaskets, ensuring a good seal at the connection. The other end is laid along the planned route to the tap location of the intermediate branch pipe of the water seal tank's replenishment pipe, ensuring a reasonable slope for drainage and venting. The tap location is determined and cut on the intermediate branch pipe of the water seal tank's replenishment pipe. After installing the flange, the connected DN50 pipe is connected to the flange. A flange connection structure is installed at the joint, facilitating subsequent pipeline inspection, maintenance, and replacement, while ensuring a tight seal to prevent leakage.

[0024] After pipeline installation, an electrical control check is performed, including inspecting the control circuit of the water treatment pump and checking the working status of electrical components such as relays, contactors, and circuit breakers. Damaged or aged components are replaced promptly. If the system has automated control functions, it can be optimized and programmed to set relevant automatic operation and alarm functions during shutdown maintenance. During shutdown maintenance, operators slowly open the valve between the clean circulating water and the water seal tank according to procedures, initially with a small opening, and then adjust according to the actual situation. Simultaneously, the valve of the original water supply branch pipe to the water seal tank is closed to stop the supply of turbid circulating water to the water seal tank. A designated person monitors the water level changes in the water seal tank in real time, using a water level gauge or visual observation. The opening of the valve between the clean circulating water and the water seal tank is adjusted as needed based on the rise or fall of the water level to ensure that the water level remains within a safe and stable range, preventing overflow or excessively low levels from affecting the operation of the heating furnace. After confirming stable clean circulating water supply and a normal water level, the water treatment pump is stopped via the control panel or remote control system. The pump's stop status and related electrical parameters are observed to ensure there are no abnormalities.

[0025] Finally, effect verification and maintenance were carried out. During the shutdown maintenance period, the water treatment pump operating time and power consumption data were recorded and compared with the data before the improvement to verify whether 450 kWh of electricity could be saved per hour. This data was based on the actual production operation of the 1580 line of the Lianggong hot rolling mill and was calculated by comparing the water treatment pump operating time and power consumption during the shutdown maintenance period before and after the improvement. A regular maintenance system was established to check for water leakage and corrosion in the pipeline, whether the valves are flexible and reliable, and whether the connections are loose. Water quality was tested regularly, and any problems were dealt with in a timely manner. Relevant operators were trained to familiarize themselves with the new operating procedures and precautions, including valve operation, water level monitoring, and emergency handling, so as to improve their skills and emergency response capabilities.

[0026] The working principle of this invention: Based on the existing pipeline system of the 1580 line of the Lianggong hot rolling mill, this invention aims to solve the problem of high energy consumption and frequent valve closures caused by the continuous operation of a 450KW pump in the raw water treatment system to maintain the water level in the water seal tank of the heating furnace. First, through on-site survey, the specific location on the clean circulating water return pipeline with stable pressure and water quality meeting the water seal tank replenishment requirements was accurately determined as the tapping point. Simultaneously, the dimensions of the intermediate branch pipe in the water seal tank replenishment pipeline were measured, laying the foundation for subsequent operations. During pipeline installation, a DN50 pipeline is selected based on the minimum water replenishment volume required for the water seal tank during shutdown maintenance, as well as parameters such as the pressure and flow rate of the clean circulating water return pipeline. A flat end is cut at the tap of the clean circulating water return pipeline, and a suitable flange is installed to ensure concentricity and secure fixing. If welding is used, quality is ensured to be defect-free. One end of the DN50 pipeline is reliably connected to the flange of the clean circulating water return pipeline to ensure a good seal. The other end is laid at a reasonable slope to the tap of the intermediate branch pipe of the water seal tank's water replenishment pipeline for easy drainage and venting. After cutting and installing the flange at the tap of the intermediate branch pipe of the water seal tank's water replenishment pipeline, the DN50 pipeline is connected to it with a flange connection structure, balancing convenience for subsequent maintenance and sealing to prevent leakage. After pipeline installation, an electrical control check is performed, inspecting the working status of electrical components such as relays, contactors, and circuit breakers in the water treatment pump control circuit. Damaged or aging components are replaced promptly. If the system has automated control functions, optimized programming is performed to set relevant automatic operation and alarm functions during shutdown maintenance. During shutdown maintenance, operators slowly open the valve between the clean circulating water and the water seal tank according to procedures, adjusting the opening degree as needed. Simultaneously, they close the original water supply branch valve of the water seal tank to stop the turbid circulating water supply. A designated person monitors the water level in the water seal tank in real time, adjusting the valve opening as needed to ensure a safe and stable water level and avoid affecting the operation of the heating furnace. After confirming stable clean circulating water supply and a normal water level, the water treatment pump is stopped, and its status and parameters are observed. Finally, by recording the water treatment pump's operating time and energy consumption data during the shutdown maintenance period, and comparing it with the data before the improvement, it was verified that 450 kWh of energy can be saved per hour. This calculation is based on the plant's actual production and operation. A regular maintenance system is established to inspect pipes, valves, and connections, and to test water quality. Operators are trained to familiarize themselves with the new operating procedures and precautions, improving their skills and emergency response capabilities. This allows for the use of clean circulating water to replenish the water seal tank during shutdown maintenance, thus achieving energy savings by stopping the water treatment pump.

[0027] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. A method for optimizing the water seal of a heating furnace in a hot-rolled plate plant to save energy, characterized in that: Includes the following steps: Draw a tap in the return water pipe of the heating furnace and connect it to the water seal tank replenishment pipe; Draw a tap on the middle branch pipe of the water seal tank replenishment pipe and connect it to the pipe coming from the clean circulation water. Taking advantage of the fact that the five water seal tanks are interconnected through pipes, water can be replenished to all water seal tanks by connecting a branch pipe. During shutdown and maintenance, open the valve between the clean circulating water and the water seal tank, close the valve of the original water supply branch pipe of the water seal tank, replenish the water seal tank with clean circulating water, and at the same time stop the operation of the water treatment pump to achieve energy saving.

2. The energy-saving method for optimizing the water seal of a heating furnace in a hot-rolled plate plant according to claim 1, characterized in that: When tapping the return water pipe of the heating furnace, select a location on the return water pipe with stable pressure and water quality that meets the water supply requirements of the water seal tank. This ensures that the water connected to the water supply pipe of the water seal tank can meet the normal operation requirements of the water seal tank and will not damage the equipment inside the water seal tank.

3. The energy-saving method for optimizing the water seal of a heating furnace in a hot-rolled plate plant according to claim 1, characterized in that: When the connecting pipe is connected to the water seal tank replenishment pipe, the pipe is a DN50 pipe. The pipe diameter is determined comprehensively based on the minimum water replenishment required by the water seal tank during shutdown and maintenance, as well as the pressure, flow rate, and other parameters of the net circulating water return pipe, so as to ensure that the water seal tank can be replenished stably and effectively during shutdown and maintenance.

4. The energy-saving method for optimizing the water seal of a heating furnace in a hot-rolled plate plant according to claim 1, characterized in that: When a tap is made on the middle branch pipe of the water seal tank replenishment pipe and connected to the pipe from the clean circulating water, a flange connection structure is set at the connection point to facilitate subsequent pipe inspection, maintenance and replacement, while ensuring the sealing of the connection point to prevent water leakage from affecting the water replenishment effect.

5. The energy-saving method for optimizing the water seal of a heating furnace in a hot-rolled plate plant according to claim 1, characterized in that: During shutdown and maintenance, after opening the valve between the circulating water and the water seal tank, the water level in the water seal tank is monitored in real time. The valve opening is adjusted in a timely manner according to the water level changes to ensure that the water level in the water seal tank is always kept within a safe and stable range, so as to avoid overflow due to excessively high water level or excessively low water level affecting the normal operation of the heating furnace.

6. The energy-saving method for optimizing the water seal of a heating furnace in a hot-rolled plate plant according to claim 1, characterized in that: After this improvement, 450 kWh of electricity can be saved per hour during shutdown maintenance. This energy-saving data is based on the actual production and operation of the 1580 line of the Lianggong hot rolling mill. It was calculated by comparing the running time and power consumption of the water treatment pumps during shutdown maintenance before and after the improvement, providing a quantitative basis for evaluating the improvement effect.

7. The energy-saving method for optimizing the water seal of a heating furnace in a hot-rolled plate plant according to claim 1, characterized in that: The method is applied to the existing pipeline system of the 1580 line of the hot rolling mill of Lianggong Steel. Without changing the overall layout of the original turbid circulating water for cooling equipment and turbid circulating water for heating furnace water seal tank in the same water supply pipeline, energy-saving improvement is achieved by simply tapping from the return water pipeline of the heating furnace and connecting it to the water supply pipeline of the water seal tank.

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