The function of the burner is to send the fuel and air into the furnace constantly, organize the air flow of pulverized coal reasonably and mix them well for rapid and stable ignition and combustion.
The oil and air must be mixed for the combustion of the fuel droplets to take place. The combustion speed depends on the evaporation speed of oil droplets and the mixing speed of oil and air. The evaporation speed of oil droplets is related to the diameter and temperature of oil droplets. The smaller the fuel droplets, the higher the temperature and the faster the evaporation. On the other hand, it is conducive to mixing and combustion. The smaller the fuel droplets, the larger the air contract surface. Therefore, the fuel oil must be atomized before combustion. And, the oil can be heated and evaporated rapidly and fully burnt after it is injected to the furnace.
Firstly, the combustion of biomass fuel is easy to control. The fuel is easy to ignite. Besides, the combustion speed is faster than that of coal.
Secondly, the biomass-fired boiler can be ignited and extinguished at any time while the coal-fired boiler cannot. The biomass-fired boiler can also be ignited automatically.
Thirdly, the biomass-fired boiler can achieve zero emission of sulfur dioxide, which belongs to environment-friendly boilers.
The temperature of flue gas generated by a biomass-fired boiler is relatively high. But it is not corrosive. So, it is suitable to use heat resisting glass fiber needled felt bag which has a good use effect. Moreover, this kind of cloth bag is not very expensive.
The selection of dust collector for coal-fired boilers is determined by the purpose and requirements of dust collecting. If the requirement is just dust collecting, the impulse bag filter is a good choice, the efficiency can reach up to 99%. If both dust collecting and desulfurization are required, you should choose bag filter plus spray desulfurization. Bag filter plus double alkali desulfurization is suggested for higher requirements.
Fuel-to-steam efficiency is a measure of the overall efficiency of the boiler. It accounts for the effectiveness of the heat exchanger as well as the radiation and convection losses. It is an indication of the true boiler efficiency and should be the efficiency used in economic evaluations. As prescribed by the ASME Power Test Code, PTC 4.1, the fuel-to-steam efficiency of a boiler can be determined by two methods: the InputOutput Method and the Heat Loss Method.
The function of high and low level alarms. Low-level alarms will draw attention to low boiler water level and, if required, shut down the boiler. High-level alarms protect plant and processes.
Where boilers are operated without constant supervision (which includes the majority of industrial boilers) low water level alarms are required to shut down the boiler in the event of a lack of water in the boiler. Low level may be caused by:
The number of passes that the flue gas travels before exiting the boiler has been a good criterion when comparing boilers. As the flue gas travels through the boiler it cools, and therefore changes volume. Multiple pass boilers increase efficiency because the passes are designed to maximize flue gas velocities as the flue gas cools. ZOZEN has developed new design technologies in our WNS series boilers allowing for comparable efficiencies in fewer passes, resulting in smaller boiler systems that will fit in tighter quarters.
