Automatic cleaning device for phosphorus sludge of yellow phosphorus tail gas fan

Abstract

The utility model provides a kind of yellow phosphorus tail gas fan phosphorus mud automatic cleaning device, including tail gas fan, the outer peripheral wall of the air inlet of tail gas fan is fixedly connected with the inner wall of tail gas pipeline, and the shaft center line of air inlet is equipped with flushing water pipeline, the water outlet of flushing water pipeline is aligned with the impeller center of tail gas fan, and vibration sensor is fixedly arranged on the shell of tail gas fan, and vibration sensor transmits the vibration frequency data of tail gas fan measured to control system.The utility model has the beneficial effects that (1) automatic monitoring and closed-loop control, completely avoid shutdown safety risk, guarantee production continuity;(2) accurate target flushing, efficiently remove phosphorus mud, maintain impeller balance, prolong fan life;(3) water temperature intelligent regulation, ensure that cleaning effect is stable under different working conditions;(4) pollution discharge path is unobstructed, avoid secondary pollution of sewage, guarantee fan normal operation;(5) pneumatic valve and water pump linkage, improve operation accuracy, reduce labor cost.

Description

Technical Field

[0001] This utility model belongs to the technical field of yellow phosphorus tail gas treatment equipment, and in particular relates to an automatic cleaning device for phosphorus mud from a yellow phosphorus tail gas blower. Background Technology

[0002] In the electric furnace process for producing yellow phosphorus in the phosphate chemical industry, a large amount of industrial waste gas, mainly composed of carbon monoxide, is generated. Since the combustion of carbon monoxide in the waste gas releases a significant amount of heat, centrifugal waste gas fans (hereinafter referred to as "waste gas fans") are commonly used in the industry to extract the waste gas to a gas holder for storage, thereby providing heat energy for the production of downstream phosphate products (such as phosphoric acid and diammonium phosphate). This process has become a key link in the yellow phosphorus production chain for energy recovery and cost reduction / efficiency improvement.

[0003] However, in addition to carbon monoxide, the exhaust gas from yellow phosphorus also contains a large amount of viscous phosphorus sludge. During the exhaust gas extraction process, the phosphorus sludge moves with the airflow and comes into contact with the fan impeller. Due to the centrifugal force generated by the impeller's rotation and the viscosity of the airflow, it gradually adheres to the impeller surface. As production continues, the phosphorus sludge accumulates on the impeller, causing an imbalance in the impeller's mass distribution. The originally symmetrical impeller structure forms "heavy areas" due to the accumulation of phosphorus sludge in certain areas, leading to a significant increase in the vibration amplitude during fan operation.

[0004] Currently, the industry's solutions to the aforementioned vibration problem are extremely rudimentary, generally employing a "periodic shutdown for manual cleaning" approach: this involves setting a fixed cycle (usually 1-3 days) based on experience, suspending the exhaust fan, disassembling the fan casing, manually scraping off the phosphorus sludge from the impeller surface, reassembling the fan after cleaning, and then resuming operation. However, this solution has serious drawbacks that are difficult to avoid in practical applications: (1) High safety risks: Yellow phosphorus tail gas is highly toxic (high carbon monoxide concentration), flammable and explosive. During shutdown and restart, the pressure of the tail gas pipeline at the inlet and outlet of the blower is prone to fluctuation, which may lead to tail gas leakage, causing safety accidents such as poisoning, fire or even explosion. At the same time, manual disassembly of the blower requires contact with phosphorus residues, which poses a risk of spontaneous combustion of elemental phosphorus or skin burns.

[0005] (2) Poor production continuity: The exhaust gas fan is the core equipment of the yellow phosphorus exhaust gas recovery system. Shutting down for cleaning will directly interrupt the exhaust gas transport and heat supply, forcing the downstream phosphate production section to reduce load or stop production. Assuming that cleaning is carried out once a day and each cleaning takes 2-3 hours, the effective production time lost due to shutdown can reach 240-360 hours per year, which seriously affects the production progress and product output.

[0006] (3) High operating costs: On the one hand, shutdown cleaning requires dedicated personnel, and the blower needs to be debugged and calibrated after cleaning, which increases labor costs and equipment maintenance costs; on the other hand, the production capacity loss and raw material waste caused by production interruption (such as the need to vent exhaust gas that is not used in time) further increase the company's overall production costs.

[0007] (4) Unstable cleaning effect: Manual cleaning relies on the operator's experience, which can easily lead to residual phosphorus mud or excessive scraping and damage to the impeller. Residual phosphorus mud will accelerate the recurrence of subsequent vibration problems, while impeller damage will shorten the service life of the fan, forming a vicious cycle of "cleaning-damage-more frequent cleaning".

[0008] With the increasing demands for production safety, efficiency, and cost control in the phosphate chemical industry, the traditional method of "periodic shutdown and manual cleaning" is no longer suitable for the needs of modern yellow phosphorus production. Therefore, developing a technical device that can monitor the fan status in real time, automatically clean the impeller of phosphorus sludge, and eliminate the need for frequent shutdowns to solve the fan vibration problem caused by phosphorus sludge adhesion and ensure the safe and continuous operation of the yellow phosphorus tail gas recovery system has become a key technical challenge that urgently needs to be addressed in the field of phosphate chemical tail gas treatment. Summary of the Invention

[0009] To address the problems in the prior art, this utility model provides an automatic cleaning device for phosphorus sludge from a yellow phosphorus exhaust fan. The technical solution includes an exhaust fan, the outer peripheral wall of the exhaust fan's inlet is fixedly connected to the inner wall of the exhaust gas pipe, a flushing water pipe is provided on the axis of the inlet, the outlet of the flushing water pipe is aligned with the center of the exhaust fan's impeller, and a vibration sensor is fixedly installed on the exhaust fan's casing. The vibration sensor transmits the measured vibration frequency data of the exhaust fan to the control system.

[0010] In a preferred embodiment, the inlet of the flushing water pipe is connected to the outlet of the water storage tank via a flushing water pump, and the inlet of the water storage tank is connected to an external water source.

[0011] In a more preferred embodiment, the water storage tank is a water tank with heating and heat preservation functions.

[0012] In a more preferred embodiment, the top of the water storage tank is also equipped with a temperature sensor, which transmits the measured water temperature data to the control system.

[0013] In a more preferred embodiment, the control system controls the start and stop of the flushing water pump based on the vibration data of the exhaust fan measured by the vibration sensor and the preset upper and lower threshold values ​​of the vibration frequency. When the vibration data is greater than the upper threshold value, the control system starts the flushing water pump; when the vibration data is less than the lower threshold value, the control system shuts down the flushing water pump.

[0014] In a preferred embodiment, the exhaust gas fan has a drain outlet at the bottom of its outer casing, which connects to the chamber where the impeller is located inside the exhaust gas fan.

[0015] In a preferred embodiment, the flushing water pump is equipped with an inlet pneumatic valve at its inlet and an outlet pneumatic valve at its outlet, both of which are controlled by a control system.

[0016] The beneficial effects of this utility model are: (1) By fixing a vibration sensor to the casing of the exhaust gas blower, the vibration frequency data of the blower is collected in real time and transmitted to the control system. Combined with the preset upper and lower limit thresholds of vibration frequency (such as upper limit 80Hz, lower limit 50Hz), a closed-loop control is formed, which does not require manual judgment. When the vibration data exceeds the upper limit (the impeller becomes unbalanced due to the accumulation of phosphorus mud), the control system automatically starts cleaning; when it is below the lower limit, it automatically stops. This design completely replaces the traditional "periodic shutdown and manual cleaning" mode, avoiding the risk of poisoning and explosion caused by exhaust gas leakage during shutdown / start-up, as well as the risk of burns / spontaneous combustion from manual contact with phosphorus mud; at the same time, it does not require interruption of exhaust gas delivery and downstream production, which can reduce the production interruption time by 240-360 hours per year, and significantly improve the operational safety and production continuity of the yellow phosphorus exhaust gas recovery system. (2) The flushing water pipe is set at the center line of the exhaust gas blower inlet, and the water outlet is precisely aligned with the center of the impeller. Compared with the defects of traditional manual scraping, which is "easy to leave residue and easy to damage the impeller", the flushing water can directly act on the core area where the phosphorus mud is attached. With the heating and heat preservation function of the water storage tank (hot water can reduce the stickiness of the phosphorus mud and improve the peeling efficiency), the phosphorus mud on the impeller surface can be quickly and thoroughly washed away, effectively restoring the mass balance of the impeller and reducing the vibration amplitude of the blower. At the same time, precise flushing avoids damage to the impeller surface caused by manual scraping, reduces the frequency of blower failures caused by impeller deformation, extends the service life of the blower by more than 30%, and reduces the cost of equipment replacement and maintenance. (3) The water storage tank has heating and heat preservation functions, and a temperature sensor is installed on the top, which can transmit water temperature data to the control system in real time. When the ambient temperature is low (such as in winter) or the phosphorus mud is highly viscous, the control system can adjust the water storage tank to maintain the water temperature (such as above 90°C) to avoid the phosphorus mud being difficult to peel off due to its high viscosity when rinsing with cold water. When the phosphorus mud is thin, the water temperature can be appropriately reduced to save energy. Compared with the problem of "sudden drop in cleaning effect under low temperature conditions" of cleaning devices without heating function, this design ensures that a stable cleaning effect can be maintained in different seasons and under different phosphorus mud conditions, avoiding repeated fan vibration due to incomplete cleaning. (4) A drain outlet is provided at the bottom of the exhaust fan casing, and the drain outlet is directly connected to the impeller chamber. The phosphorus-containing wastewater after rinsing can be quickly discharged through the drain outlet under the action of gravity and will not remain in the fan chamber. This design avoids the phosphorus mud in the wastewater from adhering to the impeller or blocking the fan flow channel, preventing the problem of "vibration recurrence in a short time after cleaning". At the same time, it reduces the corrosion of the internal components of the fan (such as bearings and seals) by the wastewater, further ensuring the stability of the fan operation. (5) An inlet pneumatic valve and an outlet pneumatic valve are installed at the inlet and outlet of the flushing water pump, respectively, and both are controlled by the control system. During cleaning, the valves open and close synchronously with the water pump to avoid delays or misoperations of the valves by manual operation. After cleaning, the valves close quickly to prevent water from leaking from the water storage tank or exhaust gas from leaking through the flushing water pipe. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0018] In the diagram: 1. Exhaust gas pipe; 2. Flushing water pipe; 3. Flushing water pump; 301. Inlet pneumatic valve; 302. Outlet pneumatic valve; 4. Water storage tank; 5. Control system; 6. Vibration sensor; 7. Exhaust gas fan; 701. Air inlet; 702. Air outlet; 8. Sewage outlet; 9. Temperature sensor. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0020] Example like Figure 1 The device shown is an automatic cleaning device for phosphorus sludge from a yellow phosphorus exhaust fan. It includes an exhaust fan 7. The outer peripheral wall of the air inlet 701 of the exhaust fan 7 is fixedly connected to the inner wall of the exhaust gas pipe 1. A flushing water pipe 2 is provided on the axis of the air inlet 701. The outlet of the flushing water pipe 2 is aligned with the center of the impeller of the exhaust fan 7. A vibration sensor 6 is fixedly provided on the outer shell of the exhaust fan 7. The vibration sensor 6 transmits the measured vibration frequency data of the exhaust fan 7 to the control system 5.

[0021] Furthermore, the inlet of the flushing water pipe 2 is connected to the outlet of the water storage tank 4 via the flushing water pump 3, and the inlet of the water storage tank 4 is connected to an external water source.

[0022] Furthermore, the water storage tank 4 is a water tank with heating and heat preservation functions.

[0023] Furthermore, the top of the water storage tank 4 is also equipped with a temperature sensor 9, which transmits the measured water temperature data to the control system 5.

[0024] Furthermore, the control system 5 controls the start and stop of the flushing water pump 3 based on the vibration data of the exhaust fan 7 measured by the vibration sensor 6 and the preset upper and lower threshold values ​​of the vibration frequency. When the vibration data is greater than the upper threshold value, the control system 5 starts the flushing water pump 3, and when the vibration data is less than the lower threshold value, the control system 5 shuts down the flushing water pump 3.

[0025] Furthermore, the exhaust gas fan 7 has a drain port 8 at the bottom outer casing, which is connected to the chamber where the impeller is located inside the exhaust gas fan 7.

[0026] Furthermore, the flushing water pump 3 is provided with an inlet pneumatic valve 301 at its inlet and an outlet pneumatic valve 302 at its outlet. Both the inlet pneumatic valve 301 and the outlet pneumatic valve 302 are controlled by the control system 5.

[0027] The operation process of the above-mentioned device is as follows: Two key parameters are set through control system 5: (1) Vibration frequency upper limit threshold (e.g., 80Hz, which can be adjusted according to actual production conditions and fan performance): When the fan vibration exceeds this value, it is determined that the impeller has too much phosphorus mud accumulation and cleaning needs to be started; (2) Vibration frequency lower limit threshold (e.g., 50Hz): When the fan vibration is below this value, it is determined that the phosphorus mud has been cleaned and cleaning should be stopped; At the same time, the insulation temperature of the water storage tank 4 is set to 90℃. The temperature sensor 9 transmits the water temperature data to the control system 5 in real time. If the water temperature is lower than 90℃, the control system will trigger the water storage tank heating function to ensure that the rinsing water is always at an efficient cleaning temperature.

[0028] After the yellow phosphorus production begins, the exhaust gas fan 7 starts and draws yellow phosphorus exhaust gas from the exhaust gas pipeline 1 through the air inlet 701, and then delivers it to the gas holder through the air outlet 702. At this time, the flushing water pump 3, the inlet pneumatic valve 301, and the outlet pneumatic valve 302 are all in the closed state, which does not affect the normal air extraction of the fan.

[0029] Vibration sensor 6 continuously collects vibration frequency data of exhaust fan 7 and transmits the data to control system 5 every 1-2 seconds. In the initial stage, the impeller is free of phosphorus sludge and the vibration frequency is stable below 50Hz, so the control system determines that cleaning is not required. Temperature sensor 9 synchronously monitors the water temperature of water tank 4. If the water temperature drops due to heat dissipation, control system 5 automatically starts the water tank heating function to maintain the water temperature above 90℃, ensuring that cleaning conditions are available at any time.

[0030] As production continues, phosphorus sludge from the yellow phosphorus exhaust gas gradually adheres to the impeller surface, causing impeller mass imbalance and a gradual increase in fan vibration frequency. When the vibration frequency measured by vibration sensor 6 reaches the preset upper limit (80Hz), an "over-limit signal" is immediately transmitted to control system 5. After receiving the signal, control system 5 first confirms through temperature sensor 9 whether the water temperature in water storage tank 4 is above 90℃ (if not, wait to heat to 100℃ before proceeding to the next step to avoid poor cleaning effect with cold water). After the water temperature reaches the standard, control system 5 opens the inlet pneumatic valve 301 to connect the water storage tank 4 and flushing water pump 3; opens the outlet pneumatic valve 302 to connect the flushing water pump 3 and flushing water pipe 2; and starts the flushing water pump 3 to pressurize the hot water in water storage tank 4 and deliver it to flushing water pipe 2. Hot water is delivered to the outlet of the flushing water pipe 2. Because the outlet is aligned with the center of the impeller (to avoid water flow washing over other parts of the blower and only act on the phosphorus sludge area, reducing water waste and internal corrosion of the blower), the hot water is sprayed directly onto the impeller surface where the phosphorus sludge is most densely attached. The hot water can significantly reduce the stickiness of the phosphorus sludge. Combined with the centrifugal force generated by the rotation of the impeller, the phosphorus sludge is quickly peeled off from the impeller surface and flows with the water to the bottom of the blower chamber. The peeled phosphorus sludge mixes with the hot water to form phosphorus-containing wastewater, which flows to the bottom of the exhaust gas blower 7 under the action of gravity and is discharged directly to the outside of the blower through the drain outlet 8. When the vibration frequency drops to the preset lower limit (50Hz), the control system 5 determines that the phosphorus sludge has been cleaned and immediately issues a "stop command" to shut down the flushing water pump 3, stop the hot water delivery, close the inlet pneumatic valve 301 and the outlet pneumatic valve 302, cut off the water circuit, prevent water leakage in the water storage tank 4, and prevent yellow phosphorus exhaust gas from backflowing through the flushing water pipe.

Claims

1. An automatic phosphorus sludge cleaning device for a yellow phosphorus exhaust fan, comprising an exhaust fan (7), characterized in that, The outer peripheral wall of the air inlet (701) of the exhaust gas fan (7) is fixedly connected to the inner wall of the exhaust gas pipe (1). A flushing water pipe (2) is provided on the axis of the air inlet (701). The outlet of the flushing water pipe (2) is aligned with the center of the impeller of the exhaust gas fan (7). A vibration sensor (6) is fixedly provided on the outer shell of the exhaust gas fan (7). The vibration sensor (6) transmits the measured vibration frequency data of the exhaust gas fan (7) to the control system (5).

2. The automatic cleaning device for phosphorus sludge from a yellow phosphorus exhaust fan according to claim 1, characterized in that, The inlet of the flushing water pipe (2) is connected to the outlet of the water storage tank (4) via the flushing water pump (3), and the inlet of the water storage tank (4) is connected to an external water source.

3. The automatic cleaning device for phosphorus sludge from a yellow phosphorus exhaust fan according to claim 2, characterized in that, The water storage tank (4) is a water tank with heating and heat preservation functions.

4. The automatic cleaning device for phosphorus sludge from a yellow phosphorus exhaust fan according to claim 3, characterized in that, The top of the water storage tank (4) is also equipped with a temperature sensor (9), which transmits the measured water temperature data to the control system (5).

5. The automatic cleaning device for phosphorus sludge from a yellow phosphorus exhaust fan according to claim 2, characterized in that, The control system (5) controls the start and stop of the flushing water pump (3) based on the vibration data of the exhaust fan (7) measured by the vibration sensor (6) and the preset upper and lower thresholds of the vibration frequency. When the vibration data is greater than the upper threshold, the control system (5) starts the flushing water pump (3). When the vibration data is less than the lower threshold, the control system (5) shuts down the flushing water pump (3).

6. The automatic cleaning device for phosphorus sludge from a yellow phosphorus exhaust fan according to claim 1, characterized in that, The exhaust fan (7) is provided with a drain port (8) at the bottom of the outer casing, and the drain port (8) is connected to the chamber where the impeller is located inside the exhaust fan (7).

7. The automatic cleaning device for phosphorus sludge from a yellow phosphorus exhaust fan according to claim 2, characterized in that, The flushing water pump (3) is provided with an inlet pneumatic valve (301) at the inlet and an outlet pneumatic valve (302) at the outlet. Both the inlet pneumatic valve (301) and the outlet pneumatic valve (302) are controlled by the control system (5).

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