Air pre-heater heating blockage treatment method

Abstract

The invention discloses an air pre-heater heating blockage treatment method. The air pre-heater is sometimes blocked, which not only influences the normal operation of the air pre-heater, but also possibly threatens the safety and economy of a power plant. The method comprises the following steps: preparing a tool configuration handle required by manual turning of the air preheater before inspection, placing the tool configuration handle on site and performing inspection; the load of a # 2 unit is stabilized between 600MW and 700MW, all main parameters of the unit are checked to be stable and normal, the combustion working condition of the boiler is stable, and the cold end of the air pre-heater is put into continuous soot blowing; water inlet electric doors of smoke coolers # 7, # 8 and # 9 on the side of the air pre-heater # 3 are closed one by one; an outlet connection air door of a blower of a # 2 furnace is gradually closed to be fully closed on site, a movable blade of a # 4 blower of a # 2 unit is relieved, the output of the # 4 blower is automatically and manually reduced, and the smoke temperature of an outlet of a # 4 air preheater is increased at the speed of not greater than 1 DEG C / min; and the output of the # 3 blower is increased while the output of the # 4 blower of the # 2 unit is reduced. The method is used for heating and blocking treatment of the air pre-heater.

Description

Technical Field

[0001] This invention relates to a method for heating and clogging an air preheater. Background Technology

[0002] Air preheaters, as indispensable auxiliary equipment in thermal power plant boilers, have the core function of preheating the air required for boiler combustion using high-temperature flue gas. This process is achieved through continuously rotating heat exchange fins, which slowly carry heat transfer elements through the low-temperature region of the flue gas, thereby facilitating heat exchange between the hot flue gas and the cold air. This mechanism not only recovers heat from the flue gas and reduces the exhaust gas temperature, thus improving boiler efficiency, but also aids in fuel ignition and combustion, reducing heat loss due to incomplete combustion. However, air preheaters can sometimes experience blockages, which not only affect their normal operation but may also threaten the safety and economic efficiency of the power plant. Summary of the Invention

[0003] The purpose of this invention is to provide a method for heating and clogging an air preheater to solve the aforementioned technical problems.

[0004] The above objectives are achieved through the following technical solutions: A method for heating an air preheater to prevent blockage, the method comprising the following steps: Step 1: Before the test, prepare the necessary tools and handles for manually turning the air preheater, place them on the spot, and conduct an inspection. Step 2: Stabilize the load of Unit #2 between 600MW and 700MW, check that all main parameters of the unit are stable and without abnormalities, ensure stable boiler combustion conditions, and put the air preheater cold end into continuous soot blowing. Step 3: Close the electric water inlet valves of flue gas coolers #7, #8, and #9 on the #3 air preheater side one by one; Step 4: Gradually reduce the outlet connecting damper of the #2 boiler blower to full closure on-site, deactivate the automatic movement of the #4 blower motor of Unit #2, manually reduce the output of the #4 blower, and increase the outlet flue gas temperature of the #4 air preheater at a rate not exceeding 1℃ / min. Step 5: Reduce the output of blower #4 of unit #2 while increasing the output of blower #3; Step 6: When the flue gas temperature of the #4 air preheater reaches 140℃, run it stably for 10 minutes, and continue to increase the flue gas temperature to run stably. Step 7: If the exhaust gas temperature of the #4 air preheater rises too quickly or reaches >210℃, increase the primary air volume of the #4 air preheater appropriately. Step 8: Closely monitor the flue gas temperature at the inlet of the desulfurization absorption tower. If the flue gas temperature at the inlet of the absorption tower exceeds 160℃, promptly activate the emergency spray cooling system.

[0005] The specific process of step one in the method for heating and clogging an air preheater is as follows: (1) Before the test, prepare the tools and handles required for manually turning the air preheater and place them on the spot; (2) During the dust removal operation, pay attention to monitoring the dust emission indicators. If necessary, increase the voltage and continuously vibrate the plates of the electrostatic precipitator on the heating side. (3) During desulfurization operation, closely monitor the flue gas temperature at the inlet of the absorption tower and check the emergency spray device at the inlet of the absorption tower to ensure its reliable standby.

[0006] The specific process of step six in the method for heating and clogging an air preheater is as follows: (1) When the flue gas temperature of the #4 air preheater rises to 140℃, it should be operated stably for 10 minutes; (2) Continue to increase the flue gas temperature to 150℃ and stabilize for 30 minutes; (3) Continue to increase the flue gas temperature to 160℃ and stabilize for 30 minutes; (4) Continue to increase the flue gas temperature to 170℃ and stabilize for 30 minutes. Beneficial effects

[0007] 1. During the testing process of this invention, a safety margin for the inlet flue gas temperature of the desulfurization absorption tower should be maintained. The inlet flue gas temperature should be below 150℃ (high alarm 160℃); otherwise, the test should be terminated. If the inlet temperature of the desulfurization absorption tower rises rapidly, the flue gas cooler should be activated immediately for cooling. If the inlet flue gas temperature of the desulfurization absorption tower exceeds the specified alarm value of 160℃, the emergency spray system of the desulfurization absorption tower should be activated. Detailed Implementation

[0008] A method for heating an air preheater to prevent blockage, the method comprising the following steps: Step 1: Before the test, prepare the necessary tools and handles for manually turning the air preheater, place them on the spot, and conduct an inspection. Step 2: Stabilize the load of Unit #2 between 600MW and 700MW, check that all main parameters of the unit are stable and without abnormalities, ensure stable boiler combustion conditions, and put the air preheater cold end into continuous soot blowing. Step 3: Close the electric water inlet valves of flue gas coolers #7, #8, and #9 on the #3 air preheater side one by one; Step 4: Gradually reduce the outlet connecting damper of the #2 boiler blower to full closure on-site, deactivate the automatic movement of the #4 blower motor of Unit #2, manually reduce the output of the #4 blower, and increase the outlet flue gas temperature of the #4 air preheater at a rate not exceeding 1℃ / min. Step 5: Reduce the output of blower #4 of unit #2 while increasing the output of blower #3; Step 6: When the flue gas temperature of the #4 air preheater reaches 140℃, run it stably for 10 minutes, and continue to increase the flue gas temperature to run stably. Step 7: If the exhaust gas temperature of the #4 air preheater rises too quickly or reaches >210℃, increase the primary air volume of the #4 air preheater appropriately. Step 8: Closely monitor the flue gas temperature at the inlet of the desulfurization absorption tower. If the flue gas temperature at the inlet of the absorption tower exceeds 160℃, promptly activate the emergency spray cooling system.

[0009] The specific process of step one in the method for heating and clogging an air preheater is as follows: (1) Before the test, prepare the tools and handles required for manually turning the air preheater and place them on the spot; (2) During the dust removal operation, pay attention to monitoring the dust emission indicators. If necessary, increase the voltage and continuously vibrate the plates of the electrostatic precipitator on the heating side. (3) During desulfurization operation, closely monitor the flue gas temperature at the inlet of the absorption tower and check the emergency spray device at the inlet of the absorption tower to ensure its reliable standby.

[0010] The specific process of step six in the method for heating and clogging an air preheater is as follows: (1) When the flue gas temperature of the #4 air preheater rises to 140℃, it should be operated stably for 10 minutes; (2) Continue to increase the flue gas temperature to 150℃ and stabilize for 30 minutes; (3) Continue to increase the flue gas temperature to 160℃ and stabilize for 30 minutes; (4) Continue to increase the flue gas temperature to 170℃ and stabilize for 30 minutes.

Claims

1. A method for heating an air preheater to prevent blockage, characterized in that: The method includes the following steps: Step 1: Before the test, prepare the necessary tools and handles for manually turning the air preheater, place them on the spot, and conduct an inspection. Step 2: Stabilize the load of Unit #2 between 600MW and 700MW, check that all main parameters of the unit are stable and without abnormalities, ensure stable boiler combustion conditions, and put the air preheater cold end into continuous soot blowing. Step 3: Close the electric water inlet valves of flue gas coolers #7, #8, and #9 on the #3 air preheater side one by one; Step 4: Gradually reduce the outlet connecting damper of the #2 boiler blower to full closure on-site, deactivate the automatic movement of the #4 blower motor of Unit #2, manually reduce the output of the #4 blower, and increase the outlet flue gas temperature of the #4 air preheater at a rate not exceeding 1℃ / min. Step 5: Reduce the output of blower #4 of unit #2 while increasing the output of blower #3; Step 6: When the flue gas temperature of the #4 air preheater reaches 140℃, run it stably for 10 minutes, and continue to increase the flue gas temperature to run stably. Step 7: If the exhaust gas temperature of the #4 air preheater rises too quickly or reaches >210℃, increase the primary air volume of the #4 air preheater appropriately. Step 8: Closely monitor the flue gas temperature at the inlet of the desulfurization absorption tower. If the flue gas temperature at the inlet of the absorption tower exceeds 160℃, promptly activate the emergency spray cooling system.

2. The method for heating and clogging an air preheater according to claim 1, characterized in that: The specific process of step one is as follows: (1) Before the test, prepare the tools and handles required for manually turning the air preheater and place them on the spot; (2) During the dust removal operation, pay attention to monitoring the dust emission indicators. If necessary, increase the voltage and continuously vibrate the plates of the electrostatic precipitator on the heating side. (3) During desulfurization operation, closely monitor the flue gas temperature at the inlet of the absorption tower and check the emergency spray device at the inlet of the absorption tower to ensure its reliable standby.

3. The method for heating and clogging an air preheater according to claim 2, characterized in that: The specific process of step six is ​​as follows: (1) When the flue gas temperature of the #4 air preheater rises to 140℃, it should be operated stably for 10 minutes; (2) Continue to increase the flue gas temperature to 150℃ and stabilize for 30 minutes; (3) Continue to increase the flue gas temperature to 160℃ and stabilize for 30 minutes; (4) Continue to increase the flue gas temperature to 170℃ and stabilize for 30 minutes.