Fluidized Bed Boiler generally refers to CFB boiler. Incineration is more economical and reasonable to treat organic waste liquid with COD≥100000mg/L and LHV≥10366kJ/kg. It can not only recycle the heat of high-concentration waste liquid, but also incinerate harmful components and protect the environment.
Fluidized Bed Boiler Selection
The furnace temperature of CFB boiler is about 900℃, so it is easy to realize desulfurization in the furnace. Staged low-temperature combustion mode ensures low NOx and SO2 emission. The slag has low carbon content and boiler thermal efficiency is high.
To effectively utilize and ensure the combustion of waste liquid, besides atomization suspension combustion, auxiliary fuel is necessary. Therefore, the boiler adopts waste liquid as main fuel, and coal as auxiliary fuel.
The boiler is single drum natural circulation bulk boiler, and ignition is with charcoal on the bed. The main combustion area is fluidized bed, with low-speed fluidization air distribution plate, air cap and isobaric air bellow. Membrane wall burn-out chamber is between furnace outlet and convection tube bundle inlet. Furnace adopts full membrane wall sealing structure, while convection tube bundle and economizer adopt tube screen membrane wall hanging structure.
Circulating Fluidized Bed Boiler Design Features
Due to high moisture and low calorific value of waste pharmaceutical liquid, we use spray gun to spray into furnace. This boiler has special furnace structure, and fluidized bed is at the bottom of furnace. The lower part of furnace has no heating surface, and adopts adiabatic combustion chamber structure.
The removal rate of harmful substances is over 99.9% when the residence time is over 5s at appropriate incineration temperature. Therefore, the boiler adopts full membrane wall furnace and U-shape burnout chamber. Convection tube bundle and economizer adopt large pitch and narrow screen width membrane wall tube panel structure (screen width ≤1.2m).
Vertical tube air preheater includes high-temperature secondary air preheater and low-temperature primary air preheater. High secondary air temperature ensures high temperature in lean-phase zone, which is conducive to stable combustion of waste liquid.
