Study On The Cleaning Treatment Of Oil-based Drilling Cuttings

The problem about how to deal well with the oil-based drilling cuttings has attracted more attention all over the world.The emission requirement about oil-based drilling cuttings have become stricter.However,the existing treatments cost too much and can't be suitable for all situations.Therefore,with the popularization of ultrasonic and microwave technology in the field of environmental protection,this study proposes to combine these two technologies with the traditional cleaning method to process the oil-based drilling cuttings.In this paper,oil-based drilling cuttings are the study object,use the oil removal rate as the index,investigates SDS cleaning treatment,ultrasonic deoiling and microwave deoiling these three kinds of single deoiling treatments.To study the effect of solution concentration,liquid-solid ratio,time and strength on the oil removal,analyze the change rule under different factors and obtain the optimum operation conditions of each single deoiling treatment.Based on the study of single deoiling treatments,we respectively couple the ultrasonic or microwave technology to the original cleaning treatment,and also study the influence of solution concentration,liquid-solid ratio as well as time.Pick out the best deoiling treatment after comparing a variety of treatments.The experimental results show that the oil removal rate could be reach over 85% under the condition of 9.0mmol/L SDS solution concentration,7:1 liquid-solid ratio,20? initial ultrasonic temperature,100 W ultrasonic power and 50 min function time.The drilling cuttings are able to meet our country's environmental emission requirement after the deoiling treatment.In addition,we carry out the economic evaluation about the best deoiling treatment,and find that the cost of ultrasound-SDS coupled deoiling treatment is located in the middle level of various treatments.Through the characterization about the samples before and after deoiling treatment,we could find that the drilling cutting is mainly compose by SiO2,the low carbon numbers components from the original oil are majority removed during the process.Through the contact angle and surface tension analysis,it is easier to remove the oil while the adhesive work is small.When the SDS surfactant is added,the contact angle between the cutting surface and the solution and the solution surface tension become decreased,which indicates that SDS is in favor of removing the oil.For the ultrasonic and microwave treatment,the change of the solution's surface tension is not obvious,so we think that these two methods to improve the deoiling effect primarily by their other particular effects.