15t/h Coal Fired Chain Grate

Product introduction

In the chain-belt grate, the chain belt itself forms the grate surface. The chain is driven by the sprockets, making the grate move slowly. The grate plates are usually made of cast iron. After assembly, the necessary ventilation gap is maintained between the grate plates, and independent air chambers with adjustable air volume are usually provided under the grate, so that air can pass through the gaps into the fuel layer for combustion. Coal falls evenly onto the grate from the coal hopper at the front end of the grate, and the thickness of the coal layer is adjusted by raising and lowering the coal gate.

As the grate moves backward, the coal layer successively completes ignition, combustion and burn-out. The ash and slag after combustion are discharged manually or mechanically. There is also a mode in which coal is not fed by the coal hopper but is thrown to the rear part of the grate by a coal spreader, with the grate moving forward. The moving speed of the grate is adjusted through gear transmission according to different coal types and boiler loads.

Applicable scope and requirements

Scope of application

The chain-belt type chain-belt grate is a mechanized layer-combustion unit, which can be used to support boilers with an evaporation capacity of 1-25t/h, and can also be used for various heating and drying equipment. It is suitable for burning bituminous coal, lignite and peat. After special design, it can also serve as biomass fuel combustion equipment burning raw materials such as bagasse, wood and rice husk.

Use requirements

The coal quality burned in this grate must meet the following requirements:

(1) The maximum particle size of the coal shall not exceed 40mm, and it is not suitable to burn coal fines below 0-5mm.

(2) The moisture content of the coal shall be less than 20%, with 8-10% being appropriate.

(3) The ash content of the coal shall not exceed 30% but shall not be lower than 10%, and the volatile matter content shall not be lower than 20%.

(4) The ash melting point temperature of the coal shall be greater than 1290℃.

(5) The caking tendency should not be too strong.

(6) The net calorific value of the coal shall not be greater than 4226kcal/kg.

(7) If the above coal quality requirements conflict with the coal feeding arrangement, the upper limit value shall be adopted.

The primary air temperature used by this grate shall not exceed 200℃.

Structure and characteristics

Component parts: 1. driving shaft; 2. driven shaft; 3. support frame; 4. ash removal device; 5. air regulating device; 6. grate chain; 7. coal hopper; 8. front air baffle plate; 9. side seals.

(1) Simple structure, low metal consumption and a large ventilation section ratio; higher strength and performance requirements are placed on the driving shaft, the driven shaft and the grate plates.

(2) Several mutually isolated independent air chambers are arranged inside the grate along the longitudinal direction. After the primary air enters an air chamber, its flow velocity decreases due to diffusion, so that it can evenly fill the whole air chamber. The air intake of each air chamber can be adjusted through the air regulating device.

(3) Every air chamber is equipped with an ash removal device. At the bottom of the air chamber there is an ash drop base plate with an ash drop opening, and a movable door connected to the ash drop pull rod normally covers the ash drop opening. When the ash removal handle is pulled periodically, the ash and slag fall from the ash drop opening onto the grate chain below, and are then carried by the grate chain to the front end or to the ash receiving hopper near the ash discharge door, and are finally removed manually.

(4) After commissioning is completed in the partner factory, the grate can run normally; it can be shipped as a whole machine, or shipped in separate parts according to user requirements.

Model parameters

Operating features

1. Compared with other chain-belt grates, it has low metal consumption and a simple structure, and is convenient to manufacture, install and operate;

2. The chain-belt grate runs reliably, burns stably and has wide fuel adaptability, and is widely used in industrial boilers.