| With the continuous progress of science and technology,powdered sulfur has played a very important role in many industries.However,dust explosion is a difficult problem to be solved in the process of sulfur comminution.Aiming at the problem of dust explosion,based on the production line of smashing sulphur,the classification type impact grinding system of sulphur powder closed nitrogen protection is proposed and designed,which provides reference for industrial application of large-scale production.First,the technological process and working principle of the sulfur powder closed nitrogen protection classification type impact grinding system are analyzed,and the design and selection of nitrogen,temperature control,grading pulverizing equipment and other equipment in the system are designed.CFD numerical simulation software FLUENT is used to study the numerical simulation of bag type dust collector,which is an important part of the grading pulverizing system.By changing the height of the airflow baffle,the change of air flow in the dust collector is observed.The structure design and selection of the bag type dust collector are provided,and the air velocity relative to the mean square is used.The root difference is used to judge the distribution uniformity of the air flow.The results show that the relative square root difference between the baffle and filter bag is relatively small,which is closer to the standard value,and the airflow inside the duster is relatively uniform.The filter speed,the area of the filter and the rising speed of the air flow are calculated,and the parameters of the process structure,such as the cleaning method,the size of the filter bag,the material and the quantity,the size of the dust collector box,etc.are determined.According to the technological process of the system,the main equipment was preliminarily debugged by single machine,and the industrial experiment of sulfur powder closed nitrogen protection graded impact grinding system was carried out.By adjusting the speed of the classifier to change the size of the graded grain and the output of the finished product,the conclusion is as follows: the whole system is prepared to feed 45 min in the early stage,and the system pressure is 12.8 kPa from negative pressure 1.1 kPa to positive pressure,and the oxygen content of the system can be stabilized around 2% within this pressure distribution,and the system can be safe after a long time operation.Stable and continuous production,considering the yield of sulfur powder,150 mu m sieve residue,particle size and energy consumption,the optimum grader’s speed is 450 r/min,the output of finished product is 1375 kg/h,the mass fraction of 150 mu m sifter is 0.74%,the particle size D90 is 72.17 mu m,and the unit power consumption is 43.079 kW h/t.In view of the sulfur powder as the fourth kind of inflammable and explosive solid dangerous goods,the paper puts forward the safety management system and safety management measures for the production personnel and system equipment,and ensures the safety of the personnel and the stable operation of the system equipment.The production line of sulphur powder closed nitrogen protection graded impact mill was set up in a factory in Guangyuan,Sichuan.After 15 months’ operation,it can be produced safely,steadily and continuously. |
