Design And Study On Experimental Flue Gas Purification Device With Finger Roller

Flue gas purification is a necessary part of the carbonization application of agricultural waste such as straw.In this paper,on the basis of the two-stage purification device for straw carbonization flue gas developed by Shenyang Agricultural University,a finger-rolling flue gas purification experimental device was designed.The effects of parameters of number of helix of fingers,finger taper,gap between the finger end to the barrel wall,on the purification rate and pressure loss are studied through numerical simulation and experiment.The main conclusions are as follows:(1)An adjustable finger-roller flue gas purification experimental device was designed and manufactured.The rotation speed,the number of helix of fingers,the finger taper,and the gap between the finger-end and the cylinder wall are adjustable,laying a foundation for the flue gas purification parameter optimization test.(2)Through the Fluent numerical simulation,the influence of the number of helix of fingers and the gap between the finger end and the barrel wall on the internal flow field of the two-stage purification device were studied.The results showed that the number of helix of the fingers has a significant effect on the tangential velocity of the airflow.When the number of helix increases,the tangential velocity increases,which is conducive to particle separation;the radial velocity is small;the axial velocity is moderate,which is conducive to rising of impurity particles.The simulation analysis of the influence of the gap between finger end to the barrel wall on internal flow field showed that the tangential velocity increases as the gap decreases,and the radial velocity and axial velocity decrease with the decrease of the gap.Therefore,the optimal range of the gap between the finger end and the barrel wall is 3～7mm,and the number of helix of the fingers rod should be 6.(3)Taking the number of helix of the fingers,the gap between the finger end and the barrel wall,and the taper of the finger as the test factors,the pressure loss and the total purification rate as the test indicators,experiment on a two-stage flue gas purification device was carried out.The optimal range of the gap between the finger end and the cylinder wall was determined through single factor test.On this basis,the optimal parameters combination in the experiment was obtained through orthogonal experiment: the number of helix of the fingers is 6,the taper of the finger is 0.05,the gap between the finger end and the cylinder wall is 5mm,then the total purification rate is 56.1% and the pressure loss is 1976 Pa.Range analysis and variance analysis on the orthogonal test results were analyzed,and the optimal parameters combination was determined as follows: the number of helix of the fingers is 6,the taper of the finger is 0.05,and the gap between the finger and the cylinder wall is 3mm.Then,the total purification rate is 57.8%,the pressure loss is 1980 Pa.And the results have been tested and verified.(4)On the basis of the single factor test of the gap between the finger and the cylinder wall,BBD experiment was carried out with the factors of the number of helix of the fingers,the rotation speed of the finger roller,the taper of the finger and the gap between the finger and the cylinder wall,and the purification rate and the dynamic pressure of the air outlet as indicators.The regression model between test factors and the purification rate and outlet dynamic pressure was established.It was concluded that the effects of the interaction between finger and barrel wall clearance and the number of helix of fingers and the interaction of finger rotation speed and finger taper on the purification rate were extremely significant;the interaction between the gap between the finger and the barrel wall and the taper of the finger has a significant impact on the purification rate.The interaction between the speed of the finger roller and the taper of the finger has a significant effect on the outlet dynamic pressure,and the interaction between the speed of the finger roller and the gap between the finger and the cylinder wall has a extremely significant impact on the outlet dynamic pressure.Under the premise of setting the purification rate weight to 0.9 and the outlet dynamic pressure weight to 0.1,the optimal parameter combination of the purification device is determined,that is,the number of helix of the fingers is 6,the taper of the finger is 0.025,and the gap between the finger and the cylinder wall It is 3mm,and the speed of finger roller is 2890r/min.Under these parameters,the purification rate is 29.24%,and the outlet dynamic pressure is 17.01 Pa.