Coal Log Pipeline—Analysis Of Coal Logs Compaction And Flow Characteristics

Coal log pipeline, a new coal transporting pipeline technology, is invented to transport coal, after being compacted to coal logs, within the pipeline. The core of the technology mainly consists of two aspects:compaction of coal logs and their flow characteristics in the pipeline, and this paper gives the main study on these two areas and respectively introduce the researches of experimental systems’design, coal logs compaction and transporting experiments.In this paper, two experimental systems, including a200-ton high-pressure automatic briquette machine and solid-liquid separated type coal log pipeline system with a diameter of50mm, had been designed and invented. The studies of this part mainly focus on systems’theoretical calculation and structural design with transition chamfering, coal log stripping device and injecting device involved, and a detailed description of the design principles and ideas can also provide a reference for future industrial design of this technology.In the coal logs compaction experiments, cationic emulsified asphalt was chosen as additional binder and the compaction condition had been reset, in order to analyze the appending proportion of binder, pulverized coal type and particle size distribution and their influence on the coal compaction process. Experimental results showed that: anthracite has the best molding characteristics, followed by bituminous and ignite coal. And for45mm coal log compaction, the critical dimensionless values θc=15.71and optimal appending proportion of cationic emulsified asphalt is8%.To analyze the coal logs kinematics in the pipe, this paper used one single coal log to research the kinematics and two coal logs to research their gap change with uphill, level, downhill three different pipe sections combinedly considered. The results have found that:coal log’s suspended velocity in the water is faster than the rate of water flow by about20%. On the downhill, uphill section, it will respectively increase and reduce the difficulty of starting coal log’s movement. What’s more, gap between pillars will remain stable when moving in the level pipe section, in the uphill will be reduced, and larger in the downhill, but the reduction of gap can be prevented by increasing the initial coal logs’gap.