SAFETY PRECAUTIONS WHEN OPERATING BOILERS

I – ESSENTIAL PREPARATIONS BEFORE START-UP:

• Safety in inspection and maintenance: Inspect all equipment to ensure no personnel or critical equipment is undergoing incomplete maintenance or repair.
• Equipment: Check all valves and doors throughout the system to ensure they are in the correct operating positions. Rotating equipment (fans, pumps, conveyors, screw conveyors, rotary valves, motors) should be able to operate freely without interference from external devices. Ensure that sensors and protective devices are complete and functioning properly. Isolation valves for sensor equipment should be fully opened (with special attention to the water level sensor in the boiler, water tank, and main steam pressure sensor). Perform at least one overall equipment inspection to ensure the boiler is in a safe operating condition.
• Electrical: Check the control electrical system. Ensure that the voltage parameters and all phases are complete. Any protection systems that prevent the boiler from starting should be rectified and restored. Before powering up the electrical system, the start switches and the equipment frequency should be in the "Off" position.
• Fuel: Check that the fuel used meets the required quantity and quality standards. If new fuel is introduced, adjust the system accordingly. Ensure that the fuel supply system is free from any obstructions.
• Personnel: Operational staff should consist of at least two personnel per shift, as per regulations. Operators must be in good health and stable condition when reporting for duty.
• Water Supply: The main water supply valves should be in the correct open position, the water treatment system should be operating normally and linked to the water level interlock in the water tank. The quality of the treated water must meet the standards required by the equipment supplier. Ensure the water source is normal and capable of providing a continuous supply, with the water supply pressure being within normal range.

II – SAFETY PRECAUTIONS DURING START-UP:

• Ignition Start-up: It is strictly prohibited to use gasoline for starting the boiler's ignition, as gasoline ignites very quickly and is difficult to control. This poses a danger to the personnel operating the boiler and may cause an explosion in the combustion chamber due to sudden expansion in severe cases.
• Temperature Increase: During start-up, it is important to adjust the temperature in the combustion chamber gradually, ensuring that it does not increase or decrease too quickly. Rapid changes in temperature can cause sudden expansion inside the equipment, leading to thermal stress on the mechanical tube bundles.

Do not supply too much fuel when the combustion chamber temperature is too low, as this may cause an excessive accumulation of fuel in the combustion chamber, which cannot ignite. In severe cases, this could lead to an explosion in the combustion chamber due to sudden expansion when ignition occurs, and it may also affect the quality of the exhaust gases.

Do not supply too much air during the start-up of a fluidized bed boiler. Adjust the air supply appropriately. Supplying excessive air during start-up (when the combustion chamber temperature is low and the thermal inertia for fuel ignition is not stable) can extinguish the burner flame and significantly reduce the combustion chamber temperature, leading to a prolonged start-up process and fuel waste.

• Protection System: Once the boiler start-up is complete and steam can be supplied, ensure that all protective devices and interlocks are activated. This will allow the boiler to operate safely.

III – SAFE OPERATION:

• Maintenance: During boiler operation, at least one qualified person should be present in the control room to ensure safe and timely operation control, load increases, load decreases, and troubleshooting. There should be full communication with on-site personnel for easy coordination.
• Weekly Inspection: During boiler operation, regular hourly inspections are required to promptly detect any abnormalities in the equipment and address them to avoid passive responses and prevent issues in the sequential connection lines. Inspections should be done using sensory checks, sound measurement devices, temperature measurements, and quality testing equipment (e.g., feed water, boiler water, fuel moisture, etc.).
• Recording: Although modern control systems such as SCADA can store all operational parameters and alarms for extended periods (months or years), recording hourly operational data is still essential. It serves as a backup for electronic devices and helps operators stay alert, allowing them to identify abnormal parameters during operation and take corrective actions.

IV – SUMMARY:

In the operation process, numerous issues (both objective and subjective) can affect the equipment. Equipment managers, operators, and maintenance personnel must have the necessary knowledge and exercise caution when working with the boiler to ensure safety during the operation of the equipment!

We hope the above article from the experienced operation team at PTH Boiler can assist our valued customers in managing and operating their equipment effectively!

The fluidized bed boiler control system from PTH Boiler is fully equipped, user-friendly, and localized in Vietnamese, making it easy for operators in Vietnam to use.