Circulating fluidized bed boiler is a specific type of boilers, and compared with the other boilers, it has certain advantages, which are: it has great improvement in combustion technology, which can improve the boiler combustion quality and combustion effect, and in turn, to improve the boiler effect. This is achieved because two return feeders are used in this type of boiler to allow the fuel to form a circulation loop between the furnace and the return feeder.
In order to improve the combustion efficiency of the boiler, in a large boiler, the combustion air is not supplied all at once, but is supplied in two times, one is supplied with the fuel that controls the rate of combustion as well as the amount of fuel that can be burned,and the other is directly supplied to the combustion process that that improves combustion efficiency. The primary air rate of the boiler refers to the proportion of the primary air. If the total air volume is 100% and the primary air rate is 70%, the secondary air rate is 30%.
There are two types of burners for industrial steam boilers, depending on how they control the mixture of air and fuel at the key point in the boiler's operation, which is the generation of combustion.
During the ignition and operation of the chamber combustion boiler fueled by pulverized coal, oil or combustible gas, improper operation can cause the deflagration or secondary combustion in the furnace or flue gas duct, which can further cause the increased pressure in the furnace. When the pressure reaches a certain value, the explosion-proof door is necessary to open automatically to protect the furnace wall of the boiler.
Boiler is a kind of thermal energy conversion equipment composed of drum and furnace. It uses fuel combustion to heat water into steam or hot water to provide power for production or help auxiliary production. With the continuous improvement of industrial manufacturing technology, boiler's control has also changed from the traditional full manual operation to the present automatic intelligent control.
Selecting a gas-fired boiler for heating a 200,000 m^2 area involves several considerations to ensure efficient, reliable, and cost-effective operation. Here’s a structured approach:
1. Determine Heating Demand
First, calculate the total heating demand of the 200,000 m^2 area. Heating demand varies based on climate, building insulation, usage, and local standards. A rough estimate for moderate climates is 100 W/m^2, but this can vary.
2. Choose Boiler Type
Decide on the boiler type. Fo...
A well designed and operated biomass boiler burning fuel within the specification of the boiler should not produce any smoke, but black smoke may be produced if the fuel is too wet for the boiler. All biomass boilers produce some oxides of nitrogen (NOx), particularly nitrogen dioxide (NO2). While NOx emissions from gas boilers have been reduced significantly in recent years through the use of low NOx burners which burn at a temperature slightly below that at which NOx forms, the nature of biomass combustion, and the need to ensure the complete combustion of wood gases, means that combustion takes place at a temperature where atmospheric oxygen and nitrogen can chemically combine. The better the quality of the combustion control system on a biomass boiler, the lower the NOx emissions will be. In general, biomass boilers produce less NOx than oil boilers. Biomass boilers do not produce any oxides of sulphur (SOx).
Combustion Efficiency
Combustion efficiency is the effectiveness of the burner only and relates to its ability to completely burn the fuel. The boiler has little bearing on combustion efficiency. A well-designed burner will operate with as little as 15% to 20% excess air, while converting all combustibles in the fuel to thermal energy.
Thermal Efficiency
Thermal efficiency is the effectiveness of the heat transfer in a boiler. It does not take into account boiler radiation and convection losses - for example, from the boiler shell, water column piping, etc.
Fuel-to-Steam Efficiency
