If the following three conditions occur during the burning and flame out process of a gas-fired boiler, the furnace is likely to blow up.
1.The residual gas content in the furnace reaches the ignition limit at the start-up phase of the furnace.
2.The fuel content in the furnace reaches the ignition limit after several times failure of ignition.
3.The fuel is sprayed out because of the halfway extinction of the flame. And, the temperature of the furnace can not meet the spontaneous combustion condition of the sprayed fuel. However, the content of the sprayed fuel reaches the ignition limit.
Four factors are related to the failure of the draft fan of the biomass-fired boiler. The factors are electric, electrical motors, dampers and induced draft fans. Therefore, if the draft fan breaks down, you can check the electric and electrical motor first, then you can check the damper and the induced fan.
1. If there is air in the pump or suction pipe, the air should be discharged.
2. If the depth of the bottom valve immersed in the water is not deep enough, the depth should be increased.
3. If the rotational speed is too slow or the conveyor belt is too loose, the rotational speed should be adjusted and the conveyor belt should be tightened.
4. If the impeller, suction pipe and bottom valve are blocked by dirt, you should check the pump body and clean the dirt.
5. If the height of water conveyance exceeds the regulations too much, the pump head should be adjusted to the specified range.
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.
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.
Package boiler is a boiler that had been fabricated and available as a complete package. The entire pressure parts have been assembled in the workshop and ready to be sent to the field or site where power plant is located. On the field/site requires only connection and integration of course work in electrical connections, water pipes, steam pipes and fuel piping system to operate. Package boiler is one of classification of boiler based on erection. Design package boilers in general are the type of Fire Tube Boiler and have made up shell and tubes. This type has high heat transfer both radiation and convection.
Evaporation phase occurs in water wall tubes. Evaporation is the process to convert water into steam. Therefore water wall tubes should be designed and constructed to provide high heat absorption, minimum excess air level and highest boiler efficiency. Construction of water wall tubes should be also constructed to prevent air leakage into steam boiler, eliminate amount of heat losses and permit high heat release and combustion rate in the furnace.
Construction of water wall tubes must provide high quality of the supporting component such as tubes, casing, refractory, lagging, tile, fin, and so on. Best construction will reduce heat loss and maintenance. Construction of water wall tubes can be classified into four types such as:
Industrial boilers are welded from sturdy steel plates that are engineered to withstand intense heat and pressure - as a result of this thick steel, boilers can sometimes weigh as much as 165 tons! The construction of hot water boilers and steam boilers is very similar. They both feature a cylinder tube, otherwise known as the pressure vessel. The pressure vessel contains something called a flame tube, which is fired through a burner and a reversing chamber that feeds flue gases back through a second smoke tube. These flue gases are reversed again via an external reversing chamber. This reversing chamber sends the flue gases to the end of the boiler, in the third smoke tube pass. A major difference between hot water industrial boilers and the steam versions? Hot water boilers, as their name implies, are usually completely filled with hot water during their operation, while steam boilers are filled with water only until the ¾ mark, with the top fourth of the boiler reserved for steam.
