What are the advantages and disadvantages of CFB boilers?

Advantages of CFB boiler. Many advantages of CFB boiler can not be realized by traditional technology. It is precisely because of these technical advantages that fluidized bed boilers have been rapidly developed and widely used. In the future, more potential should be tapped in these areas to further improve its application effect. Fluidized bed low temperature combustion technology realizes desulfurization and denitrification in the combustion process. Fuel has a wide range of applications, and can even burn crushable solid fuels with all calorific values. The discharged ash has good activity, which is beneficial to the comprehensive utilization of ash. The heating surface is in direct contact with particles, with high heat transfer coefficient and flexible arrangement of heating surface. The load regulation ratio is large, and it can run stably in the range of 35%~ 1 10% of the rated evaporation of the boiler, which is very suitable for peak shaving of the power grid, and CFB can realize long-term hot standby. The boiler island system layout of the whole boiler unit is simple, and there is no need for a very complicated fuel preparation system. The primary investment of equipment (including desulfurization and denitrification) is lower than that of pulverized coal boiler, and the operating cost of pollution control equipment is lower than that of pulverized coal boiler. At present, large and medium-sized CFB boilers have high thermal efficiency and high burnout rate, which is close to the level of pulverized coal boilers. Disadvantages of CFB boiler: the heating surface of boiler is seriously worn, which needs attention in design, operation and maintenance. The operation of the ignition process is complicated and there are many factors to consider, so the design of the ignition cylinder is still unreasonable. There are some problems in slag discharge of CFB boiler, such as poor slag discharge, insufficient cooling of slag cooler and damage of slag conveying equipment. The consumption rate of auxiliary power is high. The auxiliary power consumption rate of 135MW CFB units is generally 8. 5%~ 12. It is obviously higher than the same capacity pulverized coal boiler unit. It is easy to cause coal blockage in raw coal bunker, coal feeder and coal drop pipe. The combustible content of fly ash carried in flue gas is generally high. ) sealing and expansion problems need to be solved, especially the docking of high-pressure air duct and transition flue. The hidden danger of CFB flue blasting is obvious, but the existing equipment manufacturing and design are basically ignored, especially the process of starting and stopping is not well controlled, which is prone to deflagration. The problems of shedding, wear and cracking of refractory castable have always existed, and technical problems need to be solved urgently. Compared with conventional boiler operation, CFB boiler operation cycle is relatively short, and its reliability needs to be improved.