Study On The Preparation Process Of Mullite/Corundum Ceramics By Grading Heat Preservation

Ceramic proppant is an essential key material in hydraulic fracturing technology,and its performance directly affects efficiency of the oil extraction.Consulting the previous literatures on ceramic proppants,the sintering temperature,particle size of raw material,raw material ratio,holding time,and ball forming method have been generally studied.However,there are few reports about the preparation process by grading temperature holding time,this study on process is significant.There are a lot of coal resources and large amount of waste coal gangue in Shanxi Province,and it are still increasing year by year.Therefore,the utilization of coal gangue has become an urgent problem to be solved.Based on the principle of low-cost,mullite / corundum ceramics are prepared from coal gangue and bauxite by grading temperature preservation in order to apply the process to product ceramic proppants in the proppant plant.The research results of this paper are as follows:(1)The performance of mullite / corundum ceramic prepared from 40 % /50 % coal gangue by the grading heat preservation is better than that of ceramics prepared by constant temperature T ? holding time,and the best holding time of low temperature should be less than 1 h.(2)The optimal grading heat preservation process for preparation doped40 % coal gangue mullite / corundum ceramics is B3(low-temperature t = t3 =600 ? for 0.5 h,high-temperature T ? for 1.5 h).(3)The average resistance pressure of mullite / corundum ceramic prepared by grading heat preservation B3 is 70 MPa,which can guide preparation of ceramsite proppant for underground over a distance of 3000-4000 meters.(4)The optimal grading heat preservation process for preparation 50 %doped coal gangue mullite / corundum ceramics is C1(low temperature t = t1 =500 ? for 0.5 h,high temperature T ? 1.5 h).(5)The average resistance pressure of mullite / corundum ceramic preparedby grading heat preservation C1 is 60 MPa.which can guide preparation of ceramic proppants for underground over a distance of(generally CBM wells)under 2,000 meters.