Key Technical Research On No-power Preparation Equipment For Inflatable Composite Material Slurry

There is a huge amount of “three under”(under rail, water and buildings) coal resource in the coal mines of our country. According to incomplete statistics, there is up to tens of billions of tons of “three under” coal resource in the coal mines being used only. To meet the industry demand for coal, and at the same time avoid mining subsidence, filling mining arises at the historic moment. Using inflatable composite material slurry to complete filling mining is a new method of filling mining technology developed in recent years. Compared with other filling mining methods, it has many advantages, such as higher water content of filling slurry, better filling effect, lower cost, etc.The preparation of filling slurry is the key technology to achieve backfilling of mined-out-area. And its process mainly includes mixing of inflatable composite material slurry, slurry preparation and slurry transportation. This topic takes no-power preparation equipment for inflatable composite material slurry as research object that used in Zibo mining industry co., LTD. To solve the problems of backward equipment, complex process, high cost of filling, and material shortage of existing equipment of filling slurry preparation and transportation that hinder the development and promotion of fi lling mining technology, our team developed a new no-power preparation equipment for inflatable composite material slurry, and made an intensive study of key technologies, such as technological process of slurry preparation, powder mixing, characteristics of discharge, and centrifugal slurrying etc. In this paper, the research content mainly includes the following aspects:(1) We have developed a set of no-power preparation equipment for inflatable composite material slurry. To meet the demand of filling mining of high yield mines, this topic carried out theoretical analysis, experimental research, and numerical simulation on the key technologies, such as powder mixing, characteristics of discharge, and centrifugal slurrying etc. we put forward a new craft o f the preparation of filling slurry, and developed a set of no-power preparation equipment for inflatable composite material slurry that can realize preparation and transportation integration.(2) We have invented the diffuse mixing method of fine powder, and finished the structural design and optimization of blender. Through the field tests and analysis of Fluent, we completed the structural design of the blender, and according to factors affecting the mixing performance of the blender, such as inlet and outlet ratio, and cylinder and circular truncated cone height ratio, finished the structural optimization of it.(3) We have invented the scroll slurry preparation method of inflatable composite material slurry, and completed the structural design and optimization of centrifugal slurry preparation machine. Through the field tests and analysis of Fluent, we finished the structural design of the slurry preparation machine. And according to factors affecting the performance of slurry preparation, such as the total height of slurry preparation machine, and cylinder and cone height ratio, completed the structural optimization of it.(4) We have finished the study of discharge characteristics, explored adaptive feed rule in the process of slurry preparation. The d ischarging mode of storage silo is “negative+ gravity”, under the condition of the feed pipe diameter is invariable, vortex negative pressure determines the rate of feed flow. Through experimental study and numerical simulation of CFD, we explored adaptive feed rule in the process of slurry preparation.