The Research Of Waste Oil-based Mud Treatment And Recycling In Shale Gas Development

As the scale of shale gas exploitation constantly expands,massive waste oil-based mud oil will be produced during horizontal drilling in the process of exploitation.Direct missions of raw waste oil-based mud will not only cause severe pollution but also waste plentiful oil resources.At present,the processing technology of centrifugation-distillation applied in engineering initially has the problem of high cost and low efficiency and so on.Therefore,the research of waste oil-based mud treatment and recycling process and technology have the vital significance to the scale development of the shale gas.In the paper,on the basis of literature research,combining the problem of the waste oil-based mud oil content determination method not unified and large difference of data,this article established a set of analytical methods to measure the contents of waste oil-based mud,such as oil etc.,through the comparative study.In addition,it studied the laboratory treatment and recycling effect of three kinds of technology,ultrasonic and chemical demulsification – centrifugation experiment,centrifugal – low temperature heat distillation experiment,centrifugal-vacuum heat distillation experiment.And it laid a solid foundation for the follow-up process study.This article established a set of analytical methods to measure the oil,water,solid and other organic matter contents of waste oil-based mud by concluding research achievements at home and abroad in the field of waste oil-based mud treatment.And it presented a more convenient and accurate way to test the oil content of waste oil-based mud using ultrasonic ectraction – infrared photometric method.Through experiments about ultrasonic and chemical demulsification – centrifugation,centrifugal – low temperature heat distillation,centrifugal-vacuum heat distillation,it dedetermines the technical parameters of the treatment process,achieved the deoiling efficiency of 74.3%,83.4%,93.6% respectively.The ultrasonic and chemical demulsification – centrifugation process of waste oil-based mud dehydration obtained the dehydration efficiency of 61.5%.The two other treatment processes can dry off water in the mud.And the oil content of the waste oil-based mud residual solid was 3.6%,2.3%,0.9% respectively.The oil content of the waste oil-based mud residual solid which treated by the processes of centrifugal – low temperature heat distillation and centrifugal-vacuum heat distillation meets the standard,Technical Requirements for Pollution Control Onshore Drilling Waste Dispoasl Draft,that the oil content should less than 3% if discharged into the pool and the oil content should less than 1% if the land disposal.Combining the effects of those three techniques of treating waste oil-based mud and their economic cost,an appropriate technical solution of centrifugal – low temperature or vacuum heat distillation,which can meet the current environmental standards of waste oil-based mud harmless,resource based technology program has been preliminary proposed.