Selection and Maintenance Technology of Light Burned Magnesium Powder

It is widely used in the domestic hazardous waste disposal industry. The quality of the refractory material of the rotary kiln affects the stable operation of the rotary kiln. The price of mid-range magnesia is analyzed, and the selection and maintenance of refractory materials for hazardous waste treatment rotary kiln are analyzed for reference in specific engineering applications. Hazardous wastes have hazardous properties such as corrosiveness, toxicity, flammability, reactivity, and infectivity according to the definition of the National Hazardous Waste List. May cause harmful effects on the environment or human health and need to be managed as hazardous waste. Among them, the thermal treatment (incineration) disposal method of hazardous waste can not only completely remove the toxicity and hazard of waste, but also reduce the volume of hazardous waste to a large extent. At present, most of the newly built hazardous waste incineration and disposal projects in China prefer to use rotary kiln as the type of hazardous waste treatment furnace, which can effectively treat hazardous wastes of different shapes and phases. Light Burnt Magnesium Powder

A rotary kiln type incinerator, also known as a rotary kiln, is a slightly inclined steel hollow cylinder lined with refractory bricks. Most of the waste material is heated by the gases produced during the combustion process and the heat transmitted by the kiln walls. The solid waste is sent to the kiln for incineration from the front end, and is rotated to achieve the purpose of stirring the waste. A proper inclination must be maintained during rotation to facilitate the sliding of solid waste. In addition, waste liquid and waste gas can be sent from the kiln head or secondary combustion chamber, and even the whole barrel of waste can be sent to the rotary kiln incinerator for combustion.

Rotary kiln incineration technology is the most mainstream technology in the current hazardous waste incineration technology, and it is the most widely used furnace type. Application Incinerator, all kinds of combustible wastes of different types and shapes (granule, powder, block and barrel) can be sent to the rotary kiln for incineration.

Hazardous waste is incinerated in a rotary kiln, generally going through several stages such as drying, pyrolysis, combustion, and burnout. After 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 flue gas and slag will cause erosive damage to the refractory materials built in the rotary kiln.

(1) High temperature resistance. It can operate in a high temperature environment above 800 ℃ for a long time.

(2) High strength and excellent wear resistance. The refractory material in the rotary kiln needs to have a certain mechanical strength to withstand the expansion stress at high temperature and the stress formed by the deformation of the rotary kiln shell.

(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 in the incineration state.

(4) The thermal expansion stability is better. Although the thermal expansion coefficient of the rotary kiln shell is greater than the thermal expansion coefficient of the rotary kiln refractory material, the shell temperature is generally around 150 to 300 °C, and the temperature of the refractory material is generally above 800 °C, which may cause the refractory material ratio The thermal expansion of the rotary kiln shell is large, and it is easy to fall off.

(5) The porosity should be low. The high porosity will make the flue gas easily penetrate into the refractory material and corrode the refractory material body.