Vertical roller mill is the core equipment of the slag powder production line, the solid waste slag powder produced in the process of steel production is grinded into the high fine slag powder with high value-added, which not only solves the problem of solid waste disposal in iron and steel enterprises, but also brings new profit growth point for the enterprises. NHI has a long history of producing vertical roller mill, which is the first manufacturer of vertical roller mill in China through introducing new technology and won the "Chinese famous brand product" in this field. In 2006, NHI successfully developed MLK series slag vertical mill products on the basis of the original vertical mill technology, and drafted the corresponding industry standard JB/T10997 slag vertical roller mill. In 2007, the first MLK2650 slag vertical mill was successfully put into use in Tianjin Dazhan Cement Plant. By the end of 2019, more than 40 sets of slag vertical mill has been sold out and 3 projects of slag micro powder production line has been contracted, which has accumulated rich field experience and operation data. Through years of practical research and technology upgrading, the company's complete equipment of slag powder production line equipment has the advantages of simple process, low operation and maintenance cost, energy conservation and environmental protection.A complete slag powder production line mainly includes the storage and transportation of raw materials, slag powder mill, ore powder storage and transportation etc several workshops. The slag vertical mill is the core equipment of the production line, where the slag drying, grinding and milling can be finished. Our company has developed 7 specifications of slag vertical mill products according to different scale production line, the production capacity ranges from 30t/h to 160t/h. NHI can undertake the general contracting project of slag powder production line with an annual output of 200,000 tons ~ 1.2 million tons. NHI can also carry out customized development according to the actual production capacity needs of users.