What is the harm of scale in Industrial Boiler of Chemical Plant
What is the harm of industrial boiler scale in chemical plant? In the application process of industrial boiler in chemical plant, a large number of scaling will occur on the main heating surface of boiler due to various reasons, and the main harm of scaling is briefly introduced.
The scale will reduce the heat transfer efficiency of the boiler, and the operation boiler with the heat transfer characteristics of the waste fuel boiler has a very close relationship. From the internal inspection of the boiler, it can be seen that the scaling of the boiler occurs on the heating surface, and the higher the heating temperature is, the stronger the boiling is, and the easier it is to produce scaling. The operation practice and various data show that the harm of scaling to boiler is mainly caused by its thermal conductivity, and its thermal conductivity is 1 �� 5 of steel. The formation of scaling will lead to the decrease of heat transfer efficiency. The increase of thermal resistance is due to the waste of heat caused by fuel and the low thermal efficiency. The results show that the coal consumption is 3% more than 5% for each scale of more than 1 mm in the boiler.
Scale can shorten the service life of boiler and endanger the safe operation of boiler. From the inquiry of GB713-2014 < Steel Plate for Boiler and pressure vessel ", it can be seen that the mechanical properties of steel will decrease with the increase of boiler temperature. After the scale is produced, it exists on the water side of the heating surface, which increases the thermal resistance, and the heat generated by fuel combustion can not be well transferred to the pot water through the metal surface, which leads to the temperature of the metal heating surface rising and overheating, and the strength of the metal structure decreases. It is easy to occur smoke tube deformation, boiler drum packing, tube wall section reduction and so on, shorten the service life of boiler and related components, and seriously threaten the safe operation of boiler. In addition, it contains high levels of The scale of iron is easy to cause oxygen corrosion, scaling and corrosion on the inner surface of the pot tube, resulting in corrosion pit and other defects on the inner surface of the pot tube, and the safe operation of the dangerous boiler.
3. Scale will affect the water circulation of water circulation boiler in operation, which can be divided into natural circulation and forced circulation. The circulation of boiler water is balanced, whether rising or falling, there must be enough cross section area. The scaling of the water wall tube not only reduces the cross section area in the boiler water wall tube, but also causes the large scaling and roughness of the boiler heating surface and the large flow resistance. It will have a certain impact on the flow of water or steam in the boiler. When the pipeline is blocked by scale, the water cycle stops, and the local convective tube bundles cause local vaporization or tube explosion accidents due to the increase of pipe temperature, which directly threatens the positive of the boiler. Run often.
