The principle of primary and secondary air regulation in circulating fluidized bed (CFB) boilers is designed to maintain stable operating conditions of the boiler, adjusting the volume and temperature of primary and secondary air to achieve efficient combustion and reduce pollutant emissions. Specific adjustment strategies should be optimized and adjusted based on the boiler design and actual operating conditions.
Circulating Fluidized bed steam boiler from ZOZEN
Principles of Primary and Se...
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).
The slag produced by a biomass-fired boiler can be reused to avoid energy waste and environmental pollution. There are many ways to reuse the slag. For example, the slag can be used to improve soil and improve soil performance. If it contains potassium carbonate and organic matter, it can also be used to produce compound fertilizers. In addition, the slag is a kind of plant ash, it is also a good thermal insulation material for steelmaking.
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
After combustion, biomass-fired boiler fuel will generate energy and also produce some combustible matter in fly ash which will have bad influence on the surrounding environment. Therefore, in order to realize the goal of environmental protection, we should reduce the generation of combustible matter in fly ash in biomass-fired boiler fuel.
