Magnesium ball rotary kiln incinerator is also known as the rotary kiln, is a slightly inclined and lined with refractory brick hollow steel cylinder, most of the waste material is produced by burning gas in the process of heating and heat transfer of the kiln wall. Solid waste is sent from the front to the kiln for incineration and rotates to achieve the purpose of mixing waste. When rotating, the proper inclination should be maintained so as to reduce solid waste. In addition, the waste liquid and waste gas can be sent from the kiln head or the two chamber, and even the whole barreled waste can be sent to the rotary kiln incinerator to burn. Rotary kiln incineration of hazardous waste incineration technology is currently the most mainstream technology, is the most widely used type of furnace, is a kind of strong adaptability, can burn a variety of solid, semi solid, liquid and gas waste multi-purpose incinerator, various types and shapes (granules, powder, bulk and bottled). Combustible waste can be sent to incineration in rotary kiln. The incineration of hazardous waste in a rotary kiln usually involves several stages, such as drying, pyrolysis, combustion, and burnout. Through these stages, the harmful components in the hazardous waste are fully decomposed and destroyed under the action of high temperature, forming high temperature flue gas and slag. These high temperature fumes and slag will cause corrosive damage to the refractories built in the rotary kiln. (1) high temperature resistance. It can run in a high temperature environment over 800 centigrade for a long time. (2) high strength and excellent wear resistance.
Light burned magnesium kiln refractory material has certain mechanical strength, expansion to withstand high temperature stress and the stress and deformation of rotary kiln shell formation. (3) good chemical stability and thermal stability to resist the corrosion of chemical substances in the flue gas and to withstand the alternating thermal stress of the incineration state. (4) the stability of thermal expansion is better. The shell of the rotary kiln thermal expansion coefficient is higher than that of refractory material of rotary kiln thermal expansion coefficient, but the shell temperature is generally at about 150~300 DEG C, and refractory material to withstand temperatures are generally less than 800 DEG C, it may lead to refractory material of rotary kiln shell is larger than the thermal expansion, and easy to fall off. Because of the complex components and incineration of refractory materials, incineration wastes are easily cracked after firebricks running for a period of time, and the cracks are loosened, and the displacements and shedding between the ring and the ring are also caused. Because rotary kiln is the key equipment in the engineering technology process, the life and shedding of refractory materials directly affect the reliable and safe operation of rotary kiln. The following measures should be recommended: (1) choose excellent refractory suppliers, refractory materials should be high strength, high temperature resistant and acid resistant materials, and avoid composite refractory castables or bricks with low melting point materials such as glass. For example, the thickness of refractory material used in a hazardous waste incineration project is not less than 300mm, and the chemical composition is chrome corundum brick with Al2O3 content of not less than 80%. The apparent porosity is less than 20%, and the highest service temperature is no less than 1700 degrees. (2) the selection of the size of the refractory bricks is designed according to the characteristics of the hazardous waste provided by the project, and the outer size is considered comprehensively. (3) refractory material positioning anti-skid structure special set in the rotary kiln inside the rotary kiln in the running state of repeated start stop or not normal, refractory kiln always maintain the best balance and the expansion of the rotary kiln refractory position does not take place, to prevent the fire resistant material longitudinal and radial abnormal slide. (4) the use of advanced construction scheme is unique, change of refractory brick masonry joint fault conventional rules, using the same joint masonry, since each lap, lap and not before and after the circle, to ensure that the rotary kiln stops when no synchronous displacement does not break the refractory brick lining do the new displacement at around when do not squeeze the adjacent bricks. (5) strictly drying oven according to the oven curve, strictly manage and monitor the actual oven curve, ensure that the actual oven curve meets the design requirements, and ensure the oven pass through once, so as to ensure the quality of the oven. (6) the thickness of kiln skin attached to the surface of refractories is controlled. Hazardous waste is transported into the rotary kiln body by feeding and burning at high temperature. After burning at high temperature about 60min, the material is completely incinerated into high temperature flue gas and residue, and stable slag layer is formed. Commonly known as "kiln skin", it can play a role in protecting refractory layer. The thickness of the kiln skin is controlled within 100mm, which will lead to the uneven force of the carcass. Through the above five aspects of technical measures, the life of rotary kiln refractories is greatly extended, and the problem of falling off of refractory materials in rotary kiln has been effectively solved.