A harmless treatment process for waste oil-based mud and oil-based drilling cuttings

Abstract

The invention belongs to the field of while-drilling treatment for oil-base drilling cuttings in petroleum drilling, and particularly relates to a harmless treatment process for waste oil-base mud and oil-base drilling cuttings. Firstly, the waste oil-base mud and oil-base drilling cuttings are modified through a viscosity reducer and a demulsifier, so that the viscosity of the waste oil-base mud and oil-base drilling cuttings is lowered, and the emulsion state of oil water and oil contained in solid residues is eliminated; then colloid and asphaltene are dispersed by adding an asphalt dispersing agent; and finally washing fluid is added to wash out oil substances in the waste oil-base mud and oil-base drilling cuttings. According to the harmless treatment process, the using amount of a washing agent is greatly reduced, the viscosity reducer and the demulsifier can be recycled through settling separation, the washing fluid can be recycled through distillation, and oil-base mud sediment is heated and dried and then directly discharged when the sediment meets the environment protection standard. The harmless treatment process is applicable to on-site while-drilling treatment, no waste liquid is generated, no secondary pollution is caused, the equipment investment and operation cost is low, and the harmless treatment process has remarkable environment benefits, social benefits and economic benefits.

Description

technical field [0001] The invention belongs to the field of processing oil-based drilling cuttings while drilling, and in particular relates to a harmless treatment process for waste oil-based mud and oil-based cuttings. Background technique [0002] During the development of shale gas, diesel-based drilling fluid is used in the horizontal section of the well, and the oil-based cuttings returned from the bottom of the well are dark black, with an oil content as high as about 25%, making environmental protection treatment very difficult. Oil-based drilling cuttings contain oil, heavy metals, organic matter and other pollutants, which are national hazardous wastes. On the one hand, oil-based drilling cuttings will waste a lot of oil resources, and on the other hand, it will cause great harm to the environment. Oilfield drilling produces a large amount of waste mud or oil-based cuttings every day. Taking a horizontal well section with a length of 1000-1500 meters as an exampl...

AI Technical Summary

Problems solved by technology

However, since the solid particles in waste oil-based mud and oil-based drilling cuttings are easy to form an emulsion with oil, in order to achieve the effect of oil washing, it is necessary to add a large amount of washing liquid, which is used in large quantities and has high volatility. At the same time, centrifugal equipment There are also defects such as small processing capacity and high energy consumption, so generally speaking, the processing cost of this method is also very high

Images