Understanding the factors affecting the asphalt mixing plant combustion system can help further improve our awareness of the asphalt mixing plant. Better maintenance of the combustion system will facilitate better control during use and ensure that the plant gives full play to its performance.
The burner is the thermal component of the asphalt mixing plant that provides the heat source for the drying and heating of the gravel material. The effect of its use is directly related to the economy of operation of the whole set of equipment, temperature control accuracy, smoke emission, and other important indicators. As a key component of the asphalt mixing plant, the use of the burner adjustment is an important and complex work.
Judgment of the working condition of the asphalt mixing plant combustion system
The judgment of the equipment at the construction site, including the judgment of whether the combustion system is working properly or not, whether it needs to be adjusted, etc., is not conditioned to be realized because the equipment and means of detection are too complicated. Only through the flame color, brightness, shape, and a series of intuitive features to reflect and decide. Only by observing the flame, the most simple and effective way to carry out.
When the fuel is burned normally in the drying cylinder, the flame seen through the observation hole at the front of the cylinder should be like the following. The center of the flame is centered in the drying cylinder. The flame is evenly distributed around and does not touch the cylinder wall. The flame is full. The fire point is at a proper distance from the air outlet (nozzle) (without burning the nozzle).
The flame length is about 1/3 of the length of the drying cylinder, basically filled in the whole burning area. Small fire length should not exceed 2 m. Large fire length should not be directly ruffled to the material curtain. Burner flame diameter generally requires no more than 1.6 m. The entire flame profile is clear, no black smoke at the end, no snow flake sparks in the outer ring. Flame root oil mist evenly without black bars. The smoke outside the flame is translucent. The barrel wall material plate is clearly visible. The flame in the cylinder chamber is stable. Flame is between orange and white. Flame no jumping or strange sound.
The flame diameter is too large, which can cause serious carbon accumulation on the barrel. Too long flame will cause the exhaust gas temperature exceeds the standard and damage the dust bag. It will also scorch the material or make the material curtain covered with oil and thus affect the quality of the production material.
Classification of burners
Burners are classified into pressure atomization, medium atomization and cup atomization according to the atomization method.
Pressure atomization is to deliver the fuel to the nozzle through the high-pressure pump to atomize and then mix with oxygen for combustion. Its characteristics are uniform atomization, simple work, less consumables, and relatively low price. However, the requirements for the oil pump are high (especially when using heavy oil). The previous asphalt mixing plant mostly uses this kind of atomization way burner.
Media atomization is through 5 ~ 8kg of compressed air or with pressure vapor pressure to the periphery of the nozzle and fuel for premixing after combustion. Its characteristic is that the fuel requirements are not high (such as residual oil and other poor oil), and does not require high oil pump pressure. However, there are more consumables and the price is relatively high. Nowadays, the asphalt mixing plant uses this kind of burner due to the use of oil.
Rotor atomization is to atomize the fuel by a high-speed rotor disc (about 6000 rpm). It can burn poor oil products, such as high viscosity residual oil, etc.