Causes and treatment methods of blockage in the feeding port of waste incineration power generation incinerator

💡Common causes of blockage:

1️⃣Large objects exist in the untreated garbage: such as steel plates over 4-6㎡, steel bars or wooden blocks over 2m long, etc.
2️⃣Feeding too fast: The garbage grab opens too fast, causing several tons of garbage to hit the feeding port directly, compacting the garbage.
3️⃣Wear of the bottom plate of the feeding port: After several years of operation, many welds are severely worn, cracked and lifted, resulting in hanging materials.
4️⃣Incomplete fermentation of garbage: Feeding too fast causes the garbage to be compacted at the feeding port.

🔧 How to quickly determine the location of the blockage after the feed port is blocked?

1️⃣ Observation and hearing judgment: While the pump operator is performing forward and reverse pumping operations, other personnel look for the blockage along the pipeline. Generally speaking, the pipe section from the pump outlet to the blockage site vibrates violently, while the pipeline after the blockage point is stationary. When the concrete blockage section is knocked, the pipeline makes a muffled sound, and after the blockage point, a crisp sound is made.

2️⃣ Material layer pressure sensor: Install multiple material layer pressure sensors in the conveying system. By comparing the pressure readings at different locations, the blockage position can be more accurately located. If the pressure reading of a sensor is significantly higher or lower than that of the adjacent sensor, this may indicate that the blockage occurs between the two sensors.

3️⃣ Heat flux sensor: Heat flux sensors usually use thermocouples to measure temperature differences. When heat flows through the sensor, a temperature gradient is generated on the thermal resistance layer of the sensor. According to Fourier's law, the heat flux density passing through the sensor can be calculated. When blockage occurs, this temperature gradient changes, so that the location of the blockage can be determined.

4️⃣Microwave barrier detection sensor: ProGap 2.0 is a universal and flexible sensor based on the latest microwave technology, consisting of a transmitter and a receiver. In the above process application, ProGap 2.0 is installed on the plexiglass wall to detect the material level limit of the hopper chute. The detection of the level limit ensures the continuous filling of the incinerator grate, thereby achieving continuous combustion.

🔍 What are the common treatment measures after the feed port is blocked?

1️⃣Manual cleaning: manually clear the blockage by entering the feed port manually or using long-handled tools (such as shovels and hooks). For larger foreign objects, it may be necessary to use electric or pneumatic tools to cut or crush them.

2️⃣Mechanical dredging: Use mechanical tools such as grabs or hydraulic arms to remove blockages from the feed port or inside the furnace. For harder blockages, a crusher may be needed to break them.

3️⃣Hydraulic dredging: Use a high-pressure water gun to spray the blocked area to loosen and remove the blockage. This method is suitable for looser blockages, but care should be taken to prevent water from damaging the equipment.

4️⃣Pneumatic dredging: Use compressed air to blow the blocked area to loosen and remove the blockage. This method is suitable for drier and looser blockages.

5️⃣Vibration dredging: Use vibration equipment to vibrate the blocked area to loosen and remove the blockage. This method is suitable for blockages caused by compaction.

6️⃣Chemical dredging: For some special types of blockages, specific chemicals may be needed to soften or decompose the blockage.

7️⃣Adjust the feeding method: Change the feeding speed and method to avoid large pieces of garbage directly impacting the feeding port and reduce the possibility of blockage. Ensure that the garbage is properly pretreated and fermented before feeding.

8️⃣Regular maintenance and inspection: Regularly check the feeding port and related equipment to promptly detect and repair worn or damaged parts. Clean the feeding port and pipeline regularly to prevent the accumulation of blockages.

9️⃣Optimize garbage pretreatment: Improve the efficiency and quality of garbage pretreatment and reduce the entry of large pieces of foreign matter and non-combustibles into the incinerator. Improve the combustion efficiency of garbage through pretreatment steps such as sorting, crushing, and drying.

🛠️ What are the safety precautions when manually cleaning the feed port?

✔️Work ticket system: Emergency repair and unblocking work must apply for a work ticket, and only after it is issued and permitted can the unblocking work be carried out.

✔️Personal protective equipment: Workers entering the garbage bin must wear 3M6200 activated carbon gas masks and anti-impact goggles. Workers entering the incinerator feed port to unblock the blockage must wear safety helmets and anti-smashing work shoes correctly.

✔️Safety belts and safety ropes: Wear safety belts correctly, set horizontal safety ropes horizontally at the incinerator feed port, and use fall arresters to hang the safety belts on the safety ropes.

❌It is prohibited to use water flushing operations without cooling down: It is prohibited to use fire cannons to flush the incinerator feed port with water when the incinerator is not stopped for cooling down.

✔️Warning education: Make accident warning education display boards and post them at the positions where the accidents occurred to warn with cases. Share accidents before the shift, and gradually promote the cultural atmosphere of safety risk warnings through accident sharing.

✔️ Mechanical equipment protection: Each transmission part of the mechanical equipment must have a reliable protective device; each manhole, feeding port, screw conveyor and other parts must have a cover, guardrail and warning sign; the working environment should be kept clean and hygienic.

❌ No unrelated personnel are allowed to enter: No unrelated personnel are allowed to enter the mechanical operation site with high risk factors. If the non-machine operator must enter for some reason, he must first contact the on-duty mechanical operator and agree to enter only with safety measures. ✔️ Power supply safety: The power supply wires must be installed correctly and there must be no damage or leakage. The insulation of the motor should be good, and its terminal board should be protected by a cover.

❌ Local lighting safety: Local lighting should use a safe voltage, and 110 volts or 220 volts is prohibited.

✔️ Mechanical equipment safety inspection: Before operation, the mechanical equipment should be inspected for safety, and the empty car should be operated first. After confirming that it is normal, it can be put into use.

✔️ Safety during the operation of mechanical equipment: When the mechanical equipment is in operation, it is strictly forbidden to adjust it by hand; it is not allowed to measure parts or carry out, lubricate, clean up debris by hand. When the mechanical equipment is in operation, the operator must not leave the work station.