Experiment study on migration law of pulverized coal in borehole of coalbed methane horizontal well

in order to study the migration features and aw of the pulverzed coal in the well ore of the coalbed methane horizontal wall and to effctively control the pulverized coal production a physicalsinmulation experiment ofthe puverized coal migration in a horizontal ipe was conducted under the conition of the muti-phasefow displacement.with a method to adjusthe fovw and control the pressue diference,the paper analzed the migration features and aw of the difrent paticle size pUlverzed coal under the nclination of th diferent round pipe .The results showed that under the producion conditon.the flow state in the well bore was turbulent fowmainly and the ficw state of the large Re ynolods number as under the range of 4 00~～ 6 0.The migration mode ofthe two phase fiow pulverzed coal was slding,rollng layer movement and suspended movement and the migration of the three phase fow pulverzed cal was mainly affected by thedfferent fow mode.The pulverized .oal migration moel howed that the restrcted factorsof the pulverzed coal migration mainly were the fow.fow mode( gas and liuid ratio ,paric e size of the pulverzed coa.,ipe inc inaion and pressure diference. The above could be considered that a suitable whipstocking poimt should be selected at the drlling perod and the variaton of the we linclined angle should be contolled.The consideration of the pulverized coal properies and the vaiation of the drainage stage,ime adjustment of the water drainage strength and the pressure drop at the well botom and efe ctive control of the fovw mode in the well ore could ensure a poper pulverzed coal production inthe well bore.