The exhaust gas heat loss of coal-fired boiler is caused by the flue gas removed by final stage heat exchanger. The flue gas will take away a part of heat, mainly including the heat taken away by dry flue gas and the sensible heat with water vapor in the flue gas. What’s more, if the combustible gas in the coal-fired boiler is not completely burned, there will be heat loss as well. Therefore, this kind of heat loss mainly depends on the content of incomplete combustion products in the exhaust smoke.
Once the flameout of gas-fired or oil-fired boiler is confirmed, the boiler should be shut down for inspection and maintenance in time according to the operating regulations. Only after the inspection and test are completed, the boiler can continue to be used.
From the perspective of atomization mode, there are three kinds of burner used by boiler that are rotating cup atomization burner, pressure atomization burner and medium atomization burner.
In order to further improve the working performance of oil-fired boiler, many customers require galvanizing processing of furnace body. However, is it really effective?
The industrial pulverized coal fired boiler is a new type of industrial coal-fired boiler focusing on pulverized coal combustion technology. The impurities are well removed when the grinding fitness of pulverized coal reaches 200 mesh. The pulverized coal is easy to be ignited and has few ash contents, which can enhance the complete combustion rate and reduce the burden of dust removal.
Influencing factors of slagging on heating surface of boiler
(1) Ash characteristics of pulverized coal
Generally, the softening temperature ST of ash is used as the main indicator of slag formation. Coal with low ash melting point (ST<1200℃) is easy to slag. In addition, the slagging index also includes: silicon ratio, alkali-acid ratio, slagging index, limit viscosity and so on.
(2)Aerodynamic characteristics in the furnace
Improper air flow organization leads to flame center deviation, and the pulverized coal air flow flame adheres to the wall, causing local slagging of the water-cooled wall;
Improper air flow organization, forming flue gas retention vortex area and forming a reducing atmosphere (with CO), reducing the ash melting point and increasing the possibility of slagging.
Excess air coefficient: When the excess air in the furnace is too small, a reducing atmosphere may be generated, and the tendency of slagging will increase accordingly.
(3)Influence of boiler heat lo