1. Sufficient furnace temperature: Sufficient fuel combustion of biomass-fired boilers firstly requires high furnace temperature. The temperature should meet the requirements of sufficient fuel combustion. Besides, the combustion speed is required to be proportional to the temperature. Moreover, the furnace temperature should be raised as much as possible on the premise that slag is not formed in the furnace.
The gas consumption of 10 tph gas-fired boiler is related to technical parameters.
Such as heating surface layout, heat preservation effect, heat loss, water capacity, etc. The calculation formula of gas consumption of 10 tph gas-fired boiler is as follows:
=10 tph gas-fired boiler output÷ thermal efficiency ÷calorific value of natural gas
= 6,000,000 kcal ÷ 0.98 ÷ 8,600 kcal / h = 712 m3
Therefore, the gas consumption of 10 tph gas-fired boiler is 712 m3/ h
The gas consumption of the above gas-fired boiler is calculated at full capacity. In practice, the gas consumption changes with the operation load and operation conditions. In addition, if thermal efficiency of the gas-fired boiler is different, the gas consumption is different, too. The higher thermal efficiency is, the lower gas consumption is.
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 economizer is a heat exchanger equipment which utilizes heat recovery of flue gases to heat feedwater. It can increase boiler efficiency, reduce the temperature of flue gas and save the fuel by absorbing recovery of flue gases. Besides, the feedwater is heated through the economizer before it is supplied into steam drum to decrease the thermal stress of the steam drum wall caused by temperature difference, which can improve the operating conditions of steam drum and prolong the service life of the steam drum.
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 term “boiler efficiency” is often substituted for thermal efficiency or fuel-to-steam efficiency. When the term “boiler efficiency” is used, it is important to know which type of efficiency is being represented. Why? Because thermal efficiency, which does not account for radiation and convection losses, is not an indication of the true boiler efficiency. Fuelto-steam efficiency, which does account for radiation and convection losses, is a true indication of overall boiler efficiency. The term “boiler efficiency” should be defined by the boiler manufacturer before it is used in any economic evaluation.
