Experimental Research On Grading Vacuum Drying Technology For Oil-based Drilling Cuttings

The oil-based drilling cuttings is one of serious environmental pollution wastes.With the expansion of oil production scale,especially the offshore oil drilling, the generating amount of the oil-based cuttings is increasing and the difficulty of processing them has also increased. The oil of the drilling cuttings comes from the base oil of the drilling fluid,which is the main component of environmental pollution.Especially offshore oil-based cuttings emissions will seriously pollute the marine environment. The content of water and base oil in the oil-based drill cuttings is very high,and oil-based drill cuttings and the higher the water content of the base oil,the main purpose of harmless treatment is to make the oil content of cuttings reduce to a certain standard,and so that the oil content of cuttings can be reduced to a certain standard,the international standard for the predetermined amount of oil is less than 1%.Offshore oil-based drill cuttings treatment is usually transported to onshore processing and centrifugal drying unified treatment.The maritime transportation is costly,and the moisture content of cuttings after drying treatment by the centrifugation is still as high as 20% to 30%.The life of centrifugation is very short,and the main components wear and tear seriously and the drying efficiency is low,and it cannot work for a long time.The vacuum drying is the solid-liquid separation technology which efficiency is high and structure is simple.The degree drying means designing two different parameters to drying the water and oil in the drill cuttings.So the degrade vacuum drying technology is a new sound processing for drill cuttings,and can achieve water and oil dried of drill cuttings.This paper presents the grade vacuum drying technique which is a new harmless treatment technique for oil-based drill cuttings.And designing and developing the hierarchical vacuum drying process,then doing the research on grading vacuum drying oil-based drill cuttings with the experimental set which is composed of the experimental vacuum oven, rotary vane vacuum pump and condenser.In the first, conducting a single-stage vacuum drying characteristics of experimental research. Respectively researching the effects of drying temperature, pressure and dry type of material for the drying rate and the dry degree for hydrous materials and materials containing diesel.Then, carrying out theoretical studyfor drying model for the diesel containing material drying process.Lastly, conducting the grade vacuum drying characteristics of experimental research,and the dried object adding water and diesel.And studying the effect of drying temperature for drying rate and of drying preesure for drying degree. The results show:in a certain thickness,the drying rate can be effected mostly by the drying temperature for hydrous materials and materials containing diesel.And the GM(1,1)drying model can describe the drying process of materials containing diesel scientifically.The grade vacuum drying technique can achieve the effect of drying out the water and diesel fuel,and the first stage drying temperature should not exceed 70℃,and determining the more appropriate drying condition of the first level is 70℃, 0.3KPa by experiments. Increasing the drying temperature can be the fastest way to increase the drying rate of oil-based cuttings for the drying experiments classification of second-class diesel.And the oil content of the treated material under the experimental conditions is less than 1%.