Boiler produces heat via fuel combustion, so the burner is one of the important parts of boiler. And the air supply system is also an important component of burner. Whether the burner works well largely depends on its air supply system.
Before the operation of oil-fired boiler, we should effectively adjust the heating system to make it conform to the actual working conditions. Moreover, what are the specific operating steps when adjusting the oil-fired boiler?
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.
When regulating and controlling the coal-fired steam boiler, it will involve the banking-up operation which has a set of operating steps and points for attention. Strictly adhering to the operating steps will be helpful for the more efficient operation of coal-fired steam boiler and can extend its service life at the same time.
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.
In the adjustment of boiler operation, on the basis of ensuring safe operation, economic operation must also be achieved to improve boiler efficiency. In general boiler units, the efficiency can basically reach more than 92%, and the total loss is less than 8%. The loss is: exhaust heat loss, generally 5-6%, followed by mechanical incomplete combustion heat loss is less than 1-1.5 %, heat loss and ash slag physical heat loss are about 1%. (Physical heat loss for high ash coal ash residue will be greater).
From the point of view of quantification of indicators, the key to improving boiler efficiency is to reduce smoke loss and heat loss due to incomplete combustion of machinery. Pay attention to the flue gas temperature changes. Excessive flue gas temperature will affect the efficiency of the boiler. Too low temperature may cause low-temperature corrosion of the air preheater. Therefore, it is necessary to strengthen the adjustment according to the load changes during operation. When t
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
The fuel of a gas-fired boiler is gas such as natural gas, city gas, biogas and liquefied gas, etc. What kind of fuel the boiler burns is decided by an equipment called a burner. The boiler equipped with a gas-fired burner is called a gas-fired boiler. There are three methods of gas-fired boiler combustion as per technical characteristics of how the gas and air mix.
1. Diffusion combustion:
Gas and air mutually diffuse at the gas nozzle and are burning. The advantages are burning stably and with simple burner structure. However, the heated area is easy to be carbonized due to long flame, which is easy to produce incomplete combustion.
2. Premixed combustion:
A part of air and gas are premixed before combustion (coefficient of primary air surplus is between 0.2-0.8), and then being burned. The advantages are clear combustion flame, enhanced combustion, and high thermal efficiency.
