Online self-cleaning type spray gun for coal gas washing tower and control method

Abstract

This invention discloses an online self-cleaning spray gun and control method for a gas scrubbing tower, comprising a spray gun body, a nozzle assembly, a drain port, a valve system, and a control system. The spray gun body contains a high-pressure flushing water pipe and a main washing water pipe; the nozzle assembly includes an atomizing nozzle and a cleaning nozzle facing outwards. The valve system includes multiple valves controlling the opening and closing of the high-pressure flushing water, washing water, cleaning nozzle, atomizing nozzle, channel connection port, and drain port. The control system is connected to the valve system and is used to control the opening and closing of each valve to achieve self-cleaning flushing. This invention, through a dual-waterway structure and segmented flushing control, can comprehensively clean the exterior and interior pipes of the spray gun and the inner wall of the nozzle without shutting down the gas scrubbing tower, effectively preventing nozzle clogging, maintaining good atomization effect, and improving gas scrubbing efficiency and system operational stability. This invention has a simple structure, a high degree of automation, and is suitable for industrial spray purification systems such as blast furnace gas scrubbing towers.

Description

Technical Field

[0001] This invention relates to the field of blast furnace gas purification technology, specifically to an online self-cleaning spray gun and control method for a gas scrubbing tower. Background Technology

[0002] Blast furnace gas is a byproduct of blast furnace production and a major byproduct energy source in large steel plants, with a wide range of applications. In large steel plants, blast furnace gas is cooled and dust-removed before being transported to downstream users via gas pipelines. Most blast furnaces employ dry dust removal processes. The gas contains a large amount of chloride ions and other acidic substances, which, when mixed with liquid water in the gas, can corrode the pipelines, causing dew points and posing safety hazards. Therefore, some companies using dry dust removal processes for blast furnace gas typically install a gas scrubbing tower after the TRT (Total Thermal Removal) to remove acidic substances from the gas and extend the pipeline's lifespan.

[0003] Blast furnace gas scrubbing towers typically employ a spray scrubbing method, where circulating water is atomized and sprayed into the tower through spray guns. This ensures thorough contact between the gas and the liquid droplets, thereby removing acidic substances from the gas. As the core component of the scrubbing tower, the spray gun's atomization effect, coverage area, and operational reliability directly impact the gas scrubbing efficiency and system stability. However, in actual production operations, blast furnace gas, even after dust removal, still contains a certain amount of dust and other impurities. Furthermore, the circulating water often contains suspended solids and salt crystals. These impurities can deposit and scale at the spray gun nozzles, leading to blockages in the pipes and spray guns. Blockage in the scrubbing tower spray guns results in poor atomization and insufficient gas-liquid contact, leading to decreased gas scrubbing efficiency and the inability to remove acidic substances from the gas.

[0004] The existing solution mainly relies on stopping the scrubbing tower during blast furnace maintenance, removing the spray guns, and using high-pressure water to flush and unclog the blockage. However, blast furnaces operate continuously with limited annual maintenance time, and the gas inside the scrubbing tower is blast furnace gas (containing 20% ​​CO), requiring replacement after each cleaning. This involves high manual labor intensity and cannot be done without shutting down the system. Blockages reappear quickly after cleaning, and the gas scrubbing effect gradually decreases. Increasing the filtration level would increase system resistance and operating costs, making it difficult to balance long-term stability and economic efficiency.

[0005] The online self-cleaning spray gun for blast furnace gas scrubbing towers provided by this invention is applicable to most blast furnace gas scrubbing tower spray purification systems. It has virtually no impact on existing gas scrubbing processes and equipment layouts; simply install the spray gun of this invention at the existing spray gun location and connect it to the washing circulating water and high-pressure flushing water pipelines for operation. This spray gun utilizes a dual-waterway structure with parallel high-pressure flushing water and washing water channels, coupled with valve control, to achieve online switching between normal spraying and flushing cleaning modes. Simultaneously, by segmented flushing of the nozzle exterior, internal pipes, and nozzle inner walls, dust, salt crystals, and impurities deposited in key areas of the spray gun can be promptly removed and discharged from the system via a drainage structure, thus completing the overall cleaning of the spray gun without shutting down the system. This structure effectively reduces the probability of spray gun clogging, maintains good nozzle atomization, improves gas scrubbing efficiency, and enhances the long-term operational stability of the gas scrubbing system. Summary of the Invention

[0006] The purpose of this invention is to provide an online self-cleaning spray gun control method for a gas scrubbing tower, so as to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: an online self-cleaning spray gun for a gas scrubbing tower, comprising...

[0008] The spray gun body has a high-pressure flushing water pipe and a main washing water pipe inside, and the two channels are connected.

[0009] The nozzle assembly includes an atomizing nozzle and a cleaning nozzle; the atomizing nozzle is installed at the end of the main washing water pipe and is used to atomize the washing water; the cleaning nozzle is installed at the end of the high-pressure flushing water pipe and faces the atomizing nozzle, and is used to clean the outside of the atomizing nozzle.

[0010] The drain outlet is located below and connected to the main washing water pipe;

[0011] Valve system, including:

[0012] The inlet valve controls the flow of high-pressure flushing water;

[0013] The water inlet valve controls the flow of washing water;

[0014] Valves that control the opening and closing of the cleaning nozzles;

[0015] A valve that controls the opening and closing of the atomizing nozzle;

[0016] Valves that control the opening and closing of the connection ports between the high-pressure flushing water pipeline and the washing water channel;

[0017] Valves that control the opening and closing of sewage outlets;

[0018] The control system, connected to the valve system, is used to control the opening and closing of each valve to achieve online self-cleaning flushing.

[0019] Preferably, the high-pressure flushing water pipe and the main washing water pipe are connected at the atomizing nozzle.

[0020] Preferably, each valve in the valve system is a solenoid valve, and the control system is a programmable logic controller (PLC) electrically connected to each solenoid valve.

[0021] The present invention also provides a control method for the above-mentioned spray gun, as detailed below:

[0022] Step S1: Install the spray gun at the spray gun interface of the gas scrubbing tower, and connect the high-pressure flushing water pipeline and the washing circulating water pipeline respectively.

[0023] Step S2: Under normal spraying operation, the control system controls the washing water inlet valve and the atomizing nozzle control valve to open, and the other control valves to close, so that the washing circulating water enters the atomizing nozzle through the washing water main pipe and is sprayed out.

[0024] Step S3: When the preset flushing trigger conditions are met, the control system starts the online self-cleaning flushing mode and controls each control valve in the following order:

[0025] Open the high-pressure flushing water inlet valve and the cleaning nozzle control valve, and close the other control valves to allow the high-pressure flushing water to flush the outside of the atomizing nozzle through the cleaning nozzle.

[0026] Open the high-pressure flushing water inlet valve, the drain control valve, and the connection valve, and close other valves to allow the high-pressure flushing water to enter the main washing water pipe for flushing, and discharge the sediment and impurities through the drain outlet;

[0027] Open the high-pressure flushing water control valve, the atomizing nozzle control valve, and the connection port valve, and close other valves to allow high-pressure flushing water to enter the atomizing nozzle and flush the inner wall of the nozzle.

[0028] Reopen the high-pressure flushing water inlet valve and the cleaning nozzle control valve, close other valves, and perform a second flush on the outside of the atomizing nozzle.

[0029] Step S4: After rinsing is completed, the control system returns to the state of step S2, so that the spray gun resumes normal spraying operation.

[0030] Preferred, the preset flushing trigger condition is the preset flushing time interval.

[0031] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0032] 1. Online self-cleaning, no need to stop the machine

[0033] This invention achieves online cleaning of the spray gun under normal operating conditions by incorporating a dual-waterway structure—a high-pressure flushing water pipe and a main washing water pipe connected in parallel inside the spray gun—along with a valve and control system. This eliminates the need for furnace shutdown and manual disassembly of the spray gun, avoiding the safety risks and production interruptions associated with blast furnace gas replacement, and significantly improving the continuous operation capability of the gas scrubbing system.

[0034] 2. Segmented rinsing ensures thorough cleaning.

[0035] The control system of this invention performs segmented rinsing of the outside of the atomizing nozzle, the inside of the main washing water pipe, and the inner wall of the atomizing nozzle in a preset sequence, supplemented by a secondary external rinse. This can thoroughly remove dust, salt crystals, and other impurities adhering to key parts of the spray gun, effectively prevent nozzle clogging, and maintain a good atomization effect.

[0036] 3. Compact structure and easy to modify

[0037] The spray gun of this invention can directly replace the ordinary spray gun in the existing gas scrubbing tower. It can be put into use simply by connecting to the washing circulating water pipeline and the high-pressure flushing water pipeline. It has virtually no impact on the existing gas scrubbing process and equipment layout. The modification cost is low, the implementation period is short, and it has good applicability for promotion. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0039] In the diagram: 1. High-pressure flushing water pipe; 2. Cleaning nozzle; 3. Main washing water pipe; 4. Atomizing nozzle; 5. Drain outlet; 6. Valve system (S01-02, Z01-04); 7. Control system. Detailed Implementation

[0040] 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.

[0041] like Figure 1As shown, the spray gun mainly includes a high-pressure flushing water pipe 1, a cleaning nozzle 2, a washing water main pipe 3, an atomizing nozzle 4, a drain outlet 5, a valve system 6, and a control system 7. The valve system 6 includes valves S01 and S02 located outside the washing tower and valves Z01, Z02, Z03, and Z04 located inside the washing tower (valves Z01, Z02, Z03, and Z04 are installed near the spray gun body or nozzle assembly. Since they are in a high-humidity, high-dust, and acidic gas environment inside the washing tower for a long time, the valve body material must have good corrosion resistance and wear resistance. Corrosion-resistant stainless steel or acid and alkali resistant alloy materials can be used).

[0042] Once the device is installed at the spray gun position of the gas scrubbing tower and connected to the washing circulating water pipeline and the high-pressure flushing water pipeline, the system enters normal operation. At this time, the control system 7 controls valves S02 and Z03 to be open, and valves S01, Z01, Z02 and Z04 to be closed (the control system 7 is a programmable logic controller (PLC), and each valve is a solenoid valve, which is electrically controlled by the PLC). The washing water enters the atomizing nozzle 4 through the main washing water pipeline 3 and is sprayed into the interior of the scrubbing tower to scrub the blast furnace gas.

[0043] When the spray gun becomes clogged or the preset flushing cycle is reached during system operation, the control system 7 activates the spray gun flushing mode. First, it controls valves S01 and Z01 to open, allowing high-pressure flushing water to enter the cleaning nozzle 2 through the high-pressure flushing water pipe 1 to flush away dust and impurities deposited on the outside of the nozzle. Then, the control system closes valves Z01 and Z03 while opening valves Z02 and Z04, allowing high-pressure flushing water to enter the internal pipes of the spray gun to flush away the deposits inside the spray gun and discharge the impurities and deposits generated during the flushing process through the drain port 5. Next, the control system closes valves Z01 and Z04 and opens valves Z02 and Z03, allowing high-pressure flushing water to flow into the atomizing nozzle 4 to flush away the deposits attached to the inner wall of the nozzle. Finally, it opens valves S01 and Z01 again to flush the nozzle area again to ensure that the deposits in the key parts of the spray gun are completely removed.

[0044] After rinsing is completed, control system 7 closes valves S01, Z01, Z02, and Z04, while simultaneously reopening valves S02 and Z03, restoring the system to normal spray operation. Through this control method, online self-cleaning of the spray gun interior and nozzle exterior can be achieved without shutting down the scrubbing tower, effectively reducing the probability of spray gun clogging, ensuring good nozzle atomization, improving gas scrubbing efficiency, and enhancing the stability of the gas scrubbing system.

[0045] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An on-line self-cleaning type spray gun for a coal gas scrubbing tower, characterized by: include The spray gun body has a high-pressure flushing water pipe and a main washing water pipe inside, and the two pipes are connected. Atomizing nozzle and cleaning nozzle; the atomizing nozzle is installed at the end of the main washing water pipe to atomize the washing water; the cleaning nozzle is installed at the end of the high-pressure flushing water pipe and faces the atomizing nozzle to clean the outside of the atomizing nozzle. The drain outlet is located below and connected to the main washing water pipe; Valve system, including: The inlet valve controls the flow of high-pressure flushing water; The water inlet valve controls the flow of washing water; Valves that control the opening and closing of the cleaning nozzles; A valve that controls the opening and closing of the atomizing nozzle; Valves that control the opening and closing of the connection ports between the high-pressure flushing water pipeline and the main washing water pipeline; Valves that control the opening and closing of sewage outlets; The control system, connected to the valve system, is used to control the opening and closing of each valve, enabling online self-cleaning flushing.

2. The on-line self-cleaning type spray gun for coal gas scrubbing tower according to claim 1, characterized in that: The high-pressure flushing water pipe and the main washing water pipe are connected at the atomizing nozzle.

3. The on-line self-cleaning type spray gun for coal gas scrubbing tower according to claim 1, characterized in that: Each valve in the valve system is a solenoid valve, and the control system is a programmable logic controller (PLC) that is electrically connected to each solenoid valve.

4. A control method of the online self-cleaning type lance for a coal gas scrubbing column according to any one of claims 1 to 3, characterized in that, Includes the following steps: Step S1: Install the spray gun at the spray gun interface of the gas scrubbing tower, and connect the high-pressure flushing water pipeline and the washing circulating water pipeline respectively. Step S2: Under normal spraying operation, the control system controls the opening of the washing water inlet valve and the atomizing nozzle control valve, and closes the other control valves, so that the washing circulating water enters the atomizing nozzle through the washing water main pipe and is sprayed out. Step S3: When the preset flushing trigger conditions are met, the control system starts the online self-cleaning flushing mode and controls each control valve in the following order: Open the high-pressure flushing water inlet valve and the cleaning nozzle control valve, and close the other control valves to allow the high-pressure flushing water to flush the outside of the atomizing nozzle through the cleaning nozzle. Open the high-pressure flushing water inlet valve, the drain control valve, and the connection valve, and close other valves to allow the high-pressure flushing water to enter the main washing water pipeline for flushing, and discharge the sediment and impurities through the drain outlet; Open the high-pressure flushing water control valve, the atomizing nozzle control valve, and the connection port valve, and close other valves to allow high-pressure flushing water to enter the atomizing nozzle and flush the inner wall of the nozzle. Reopen the high-pressure flushing water inlet valve and the cleaning nozzle control valve, close other valves, and perform a second flush on the outside of the atomizing nozzle. Step S4: After rinsing is completed, the control system returns to the state of step S2, so that the spray gun resumes normal spraying operation.

5. The control method according to claim 4, characterized in that: The preset flushing trigger condition is the preset flushing time interval.

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