rotary kiln refers to rotary calcination kiln (commonly known as rotary kiln), which belongs to the category of building materials equipment. rotary kiln can be divided into cement kiln, metallurgical and chemical kiln and lime kiln according to different materials. cement kiln is mainly used for calcining cement clinker, which can be divided into two categories: dry kiln and wet kiln. metallurgical and chemical kilns are mainly used for magnetizing roasting of lean iron ore in iron and steel plants of metallurgical industry; oxidizing roasting of chromium and nickel iron ore; roasting of high-bauxite vanadium ore and clinker and aluminium hydroxide in bauxite plants of refractory materials plants; roasting of chromium ore sand and chromium ore powder in chemical plants. lime kiln (active lime kiln) is used to roast active lime and light-burning dolomite for iron and steel plants and ferroalloy plants.
rotary kiln is widely used in many industries, such as building materials, metallurgy, chemical industry, environmental protection and so on. rotary cylinder equipment is widely used to treat solid materials mechanically, physically or chemically. this kind of equipment is called rotary kiln. rotary kiln application originated from cement production, in 1824 british cement worker j asp invented the intermittent operation of the earth kiln; in 1883, ditz germany invented the multi-layer continuous operation of the shaft kiln; in 1885, the british lansam (eransome) invented the rotary kiln, after obtaining patents in britain and the united states, put it into production, and soon achieved considerable economic results. benefit. the invention of rotary kiln makes cement industry develop rapidly, and promotes people's research on the application of rotary kiln. very soon, rotary kiln is widely used in many industrial fields, and becomes more and more important in these production, becoming the core equipment of corresponding enterprises. in the application field of rotary kiln, cement industry has the largest number.
1. its technological performance and operation determine to a great extent the quality, output and cost of enterprise products. "as long as the kiln turns, there will be tens of millions of people." this folk song is a vivid description of the importance of rotary kiln in production.
2. in building materials industry, rotary kiln is used not only to forge cement clinker, but also to forge clay, limestone and slag drying. in refractory production, rotary kiln is used to forge raw materials to stabilize its size, increase its strength and reprocess.
3. in the process of mineral processing, the lean iron ore is magnetized by rotary kiln, so that the original weak magnetism of the ore is changed to strong magnetism, so as to facilitate magnetic separation.
4. in chemical industry, baking soda, phosphate fertilizer and barium sulfide are produced in rotary kiln. in the 1960s, lapple et al. invented a new process for producing phosphoric acid in rotary kiln. the method has the advantages of low energy consumption, less electricity consumption, no use of sulphuric acid and the utilization of medium and low grade phosphate rock.
5. the whole production process of cement is summarized as "two grinding and one burning", in which "one burning" is the process of burning raw materials prepared by grinding into clinker under the action of high temperature in rotary kiln. therefore, rotary kiln is the main part of cement production, commonly known as the "heart" of cement plant.
6. in terms of environmental protection, the developed countries in the world have used cement kilns to incinerate hazardous wastes and garbage for more than 20 years. this not only reduces and harmlessly reduces waste, but also uses waste as fuel, saves pulverized coal and realizes the recycling of waste.