
The construction principle and process of reverse construction method are introduced and its application advantages are analyzed in this paper.Reverse construction method can improve the safety of underground engineering,significantly save project costs,shorten construction period,and prevent the subsidence of surrounding foundation.It is an underground engineering construction technology that has a great development prospect and is worth popularizing.
The theory and method of optimized rock blasting are described.The optimal rock crushing principle,optimal explosive unit consumption principle,energy balance distribution principle,crushable energy band distribution principle,single-hole blasting optimal crushing principle,and surface-to-energy ratio mediatization principle for the blasting zone are proposed.Based on these principles,methods for blasting design and prediction of blasting blocks are put forward to achieve the goal of rock blasting optimization.
The straight grate technology based pellet production line faced the problem of high process energy consumption in the early stage of production.Through a series of attempts and explorations,a scheme is summarized to reduce the energy consumption of the straight grate technology based pellet production process throughout the whole process from raw materials to finished pellets,including measures such as zoned storage of iron ore concentrate raw materials,renovation of intelligent pelletizing system,optimization of induration system,and reduction of desulfurization and denitrification energy consumption.After a year of on-site practice in 2021,it's verified that the scheme to reduce energy consumption in the straight grate technology based roasting pellet process has achieved good energy-saving results.The energy consumption in the pellet process has reached 21.80 kgce/t,a decrease of 5.74 kgce/t from 2020,and the energy consumption indexes are among the best in domestic peers.
Through the exploration and practice of excavation and supporting technology for crushing chambers under underground confined space conditions in Miaogou Iron Ore Mine,an innovative excavation and supporting technology scheme for large chambers using various excavation and supporting methods has been formed,which achieves the goal of accelerating engineering construction speed and ensuring the safety and efficiency of the construction.