We have a 10-ton boiler that people call a boiling furnace; is it a chain furnace?

A fluidized bed furnace is completely different from a chain grate furnace. The material used in a fluidized bed furnace is pulverized coal mixed with cinder; the fuel burns in a state of \"fluidization\" caused by air flow within the furnace, and no equipment such as a chain slag extractor is required. The burned ash and slag flow out through an ash discharge port at the bottom of the furnace.

In ammonia production plants that use coal as fuel, the boiling furnaces are typically designed to burn gas-making slag; nowadays, mixed-fuel furnaces that utilize waste materials are being used

The slag from chain furnaces can be used as fuel in fluidized bed furnaces after being crushed.

The two are different. A boiling furnace primarily burns coal particles, coal shreds, and pulverized coal of a certain particle size; coal is fed in from the side, and air is introduced into the furnace evenly from the bottom through air nozzles using a blower. Inside the furnace, there is a layer of material of a certain thickness that is in a \"boiling\" state. The flue gas and ash rise through the furnace, superheater, economizer, and dust collector before being discharged by an exhaust fan. There are certain requirements regarding the particle size of coal and the amount of gangue; large pieces or excessive amounts of stones must not be allowed to enter, as this can cause accidents such as furnace blockage that lead to shutdowns. A portion of low-calorie materials such as coal cinders can be mixed in, but their specific gravity and particle size must meet the requirements. Chain stoves are relatively simple, so they won’t be described here.

Boiling furnaces and chain grate furnaces differ in their combustion methods: a boiling furnace is a coal-fired boiler that represents one of the new combustion technologies developed in recent years. The working principle of a boiling boiler is to use air to blow coal dust that has been crushed to a certain particle size, causing it to burn in a boiling state at a certain height within the furnace. The combustion of coal in a fluidized bed furnace takes place not on a grate, nor does it burn suspended in the air as in a pulverized coal furnace; instead, it occurs on the bed of material in the fluidized bed furnace. The outstanding advantage of the fluidized bed furnace is its wide adaptability to different types of coal; it can burn bituminous coal, anthracite, lignite, and coal gangue. The average temperature of the boiling material layer is generally between 850 and 1050°C. The layer is quite thick, acting like a large heat storage tank; fuel accounts for only about 5% of its composition. When new coal particles enter this layer, they mix with the extremely hot particles whose temperature is several dozen degrees higher, allowing them to burn quickly. Therefore, coal gangue can be used as a substitute. Production experience shows that boilers can operate normally using coal gangue with a ash content as high as 70% and a calorific value of only 7.54 MJ/kg; 40% to 50% of the heat can be obtained directly from the bed layer. A chain furnace is a mechanical boiler that burns coal briquettes, with the grate fixed to a chain. The chain drives the grate to move slowly; coal is added in front of the furnace and burns gradually as the grate moves. It is widely used in steam boilers and hot air stoves of medium and small capacity.