As the earliest company engaged in technology development and project construction of rotary kiln，ACRE has been leading the technology development trend of lime kiln.This paper introduces the technical difficulties and design difficulties of the 1 200 t/d self developed large scale active lime rotary kiln，this kiln type has the largest production capacity at present,and its main structure and control system are also comprehensively improved which have reached world advanced level.

There were challenges and opportunities for the lime industry in the year of 2018,and vigorously transformation and upgrading were carried out in this year,all kinds of gas-fired lime kilns have been greatly developed,among them the advantages of the kilns which fired with high calorific value gas were well known to all. This paper discusses the technologies of all kinds of gas-fired kiln,the recent trend of expending to low calorific value gas,and the problems involved in the reduction of the heat value of the gas.

The rotary kiln of active lime works with coal powder as fuel,which leads a circle shape dust liner inside the kiln.While the ring formation is getting worse and inside diameter of kiln is smaller,the factor of material filling is bigger,the thermodynamic engineering is damaged,the negative influence on the kiln comes for the output,quality and safety.Based on both analysis of active lime process and study of laboratory work,the paper gives the ring formation theory of rotary kiln with coal powder as fuel,and offers an efficient handling technology for the dust liner.

The sliding nozzle mechanism for ladle is developed for the improvement of steel-making technologies such as continuous billet casting and external refining and improvement of operation conditions of casting steel production.This paper introduced the features and improvements of FLOCON sliding nozzle mechanism.

When using mixed gas in Maerz kiln,by understanding the principle of the air-gas ratio,the proper equilibrium point of air-gas ratio will be determined to improve the comprehensive utilization of the kilns.

According to the characteristics of cord steelmaking and the requirements of working conditions,this paper introduces the requirements of the refractories used for steel ladles and analyzes the development history and present situation of refractories for the ladle of cord steelmaking.After comparing the advantages and disadvantages of the refractories currently being used,some new ideas and views on the use of refractories for the future are put forward.

The vertical compound crusher  has the disadvantages of low crushing efficiency,hammer head easy abrasion,and high maintenance intensity efficiency.Through many technical demonstration and mine investigation,a new type  and advanced crusher is put into use in the  lime crushing production,and analysis and adjustment are taken on crushing efficiency,hammer head and operation maintenance.It is found that the production runs well and the crushing efficiency and the service life achieves the expected results.