The influence of the cooling air volume on the boiler air intake is generally controlled within the allowable air excess coefficient, so the heated hot air is transported to the furnace through the dry slag machine mesh belt and does not affect the normal operation of the boiler. However, if the boiler air excess coefficient is strictly required, the hot air can also be transported to the boiler air supply system for reuse. The cooling air volume usually requires ≯ 1% of the total combustion air volume of the boiler; when the air temperature entering the furnace is >340℃, the cooling air volume can be increased to 1.5~2%.
Our company's dry Slag Machine Mesh Belt is not only widely used in China, but also widely used all over the world, especially in Southeast Asian countries. The current installed capacity can meet 1000MW units. This type of dry slag machine is mainly composed of driving system, conveying/cleaning system, hydraulic tensioning system, conveying roller, air inlet system, shell, etc. The conveying system adopts stainless steel mesh belt transmission (as shown in Figure 2), with fixed bearing scales on it, which is used to convey and cool high-temperature ash. The cleaning system is driven by a double-ring chain chain, and the scraper is dragged to clean the ash that falls off the bottom of the accumulated shell. In addition, air inlets are provided on the housing and head of the equipment to suck in ambient air to cool the internal high-temperature ash.
The tensile strength of stainless steel mesh belt: 532kN for 1400mm mesh belt, 608kN for 1600mm mesh belt, and the annual stretch rate (including elongation and wear) is about 1 to 2%. Sweeping chain usually adopts φ18×64 high wear-resistant chain, and some small units adopt φ14×50 specification.
Dry Slag Machine Mesh Belt Analysis of advantages and disadvantages: The conveyor belt is driven by the friction force of the driving roller, and the transmission is stable, and the wear is small, but the overload is easy to slip. The cleaning system at the bottom can eradicate the ash and slag at the bottom of the equipment. However, a set of systems is added and an accident point is added. Increased power consumption, not suitable for large inclination conveying; the mesh belt has a slat pitch of about 70mm, a large air gap, and a good cooling effect, but there is more dust leakage, and the cleaning system has a large load and abrasion; the steel belt conveying process adopts a simple support shaft Support, reasonable force. The mesh belt and scale of the conveying steel belt are made of heat-resistant stainless steel, which has good temperature resistance, but has low thermal conductivity and high cost of stainless steel.