Views: 1994 Author: Site Editor Publish Time: 2022-09-01 Origin: Site
The waste heat boiler has a variety of types according to different flue gas compositions, but the same is that the flue gas composition is complex, and the flue gas contains a large amount of dust and cohesive ash in molten state. These ashes will be re bonded on the heating surface of the boiler with the decrease of flue gas temperature, resulting in ash deposition and coking, which will reduce the heat transfer effect of the heating surface, reduce the boiler output and increase the exhaust gas temperature, Therefore, ash removal must be considered in the design of waste heat boiler.
Jiangsu Sifang waste heat boiler uses the sensible heat in the waste gas, waste or waste liquid in the industrial process or (and) the heat generated after the combustion of its combustible materials to heat the water to a certain temperature and provide hot water or steam to other sections for use, greatly improving the utilization rate of fuel combustion and reducing costs and increasing benefits for enterprises. The waste heat boiler has the advantages of high thermal efficiency, long service life, safety and reliability, and convenient maintenance. After the flue gas treatment, it meets the environmental protection standard, reduces the environmental protection pressure of the enterprise, and helps the green development of the enterprise.
In order to ensure the cleanness of the heating surface, remove the slagging, improve the heat transfer efficiency and reduce the exhaust gas temperature, we often use the ash removal device. Common soot cleaning devices are mainly divided into steam soot blower, acoustic soot blowing, shock wave soot blowing and mechanical vibration soot cleaning.
1. Steam soot blower is a traditional soot blower, which uses high-temperature and high-pressure steam to directly purge the heating surface. It is a commonly used soot cleaning method for waste heat boiler. It is most widely used and most effective and reliable at present. However, due to the complex structure of the system and the characteristics of the medium, as well as the influence of the high temperature environment, the equipment failure rate is relatively high and the maintenance level is required to be high.
2. Acoustic soot blower technology is to convert compressed air (or steam) into high-power acoustic wave or infrasonic wave (a pressure wave that propagates in space medium (gas) in the form of density wave) and send it into the furnace. When the ash on the heating surface is repeatedly pulled and pressed by the density wave that alternates with a certain frequency, it falls off due to fatigue and looseness, and is carried away with the flue gas flow, or under the action of gravity, it sinks to the ash hopper for discharge. The soot blowing device is simple in equipment system, safe in use, small in maintenance, low in cost and high in energy utilization. Its disadvantages are that the energy is small, the soot blowing effect is not obvious, the existing soot can not be removed, and there is no effect on coking.
3. The working principle of gas pulse shock wave soot blower is to mix air and combustible gas (such as hydrogen, acetylene, coal gas, liquefied gas and natural gas) in a proper ratio, mix them in a special container, and generate deflagration after high-frequency ignition. The huge acoustic energy and a large amount of high-temperature and high-speed gas generated instantaneously oscillate, impact and wash the heating surface tube bundle in the form of shock wave, so that the ash splashes on its surface and is carried away with the flue gas. It has good effect on removing dust and coking. However, it has the disadvantage of low safety performance. Soot blowing scours the heating surface for a long time, which is easy to damage the pipe wall. At the same time, there is explosion risk due to gas.
4. The mechanical rapping device uses a small capacity motor as the power, drives a long shaft to rotate at low speed through the transmission, hangs many rapping hammers on the shaft in equal phases, and hammers the heating surface of the boiler in order. At the moment of hammering, the heating surface will vibrate strongly, and the adhered ash will be subjected to repeated stress to produce tiny cracks until the adhesion of the ash is damaged and falls off.
Several kinds of ash cleaning devices have their own advantages and disadvantages. In the actual application process, a variety of ash cleaning devices are used together, with better effects and more comprehensive functions.
The above is the answer of Jiangsu Sifang boiler to this question. If you have any questions about the boiler, please consult the online customer service of Jiangsu Sifang boiler or call 0516-85871846 and 0516-85532705. The professional and technical personnel of Jiangsu Sifang boiler will answer your questions in time.