Staged vacuum drying treatment process and treatment device for oilfield drilling cuttings

Abstract

The invention relates to a staged vacuum drying treatment process and a treatment device for oilfield drilling cuttings. During auxiliary heating, the inside of a dryer is pumped to reach different levels of vacuum degrees by a vacuum set, water and diesel in the oilfield drilling cuttings are sequentially vaporized by staged vacuuming, vapor is liquefied by a condenser, the water containing a small amount of oil is recovered to a water storage tank, the diesel containing a small amount of water is recovered to an oil storage tank for reserve, the drilling cuttings are discharged after dried, and a heating system is automatically started or stopped as needed. By the aid of the drying treatment process and the drying treatment device, the oil-based drilling cuttings can be dried to such a degree that the water content is lower than 0.1% and the oil content is lower than 0.3%, and the drilling cuttings can be maximally reduced and directly discharged. The treatment device can respectively recover the diesel and the water by the aid of the same condenser under a staged vacuum condition, a huge fractionating tower is omitted, and the device is compact in structure, simple and convenient to operate, high in drilling cuttings treatment efficiency, fine in environmental performance and suitable for harmless treatment of the oil-based drilling cuttings on an open sea or deep sea drilling platform.

Description

technical field [0001] The present invention relates to oilfield drilling oily drill cuttings graded vacuum drying treatment process and a processing device used for implementing the process, which belongs to the field of oil field environmental protection, can be used for drying treatment of oily drill cuttings or oily sludge, and is especially suitable for drilling platforms in far sea or deep sea areas Harmless treatment of oil-based drilling cuttings. Background technique [0002] At present, oil-based drilling fluid is widely used in drilling technology. The oil used as the continuous phase in water-in-oil drilling fluid is called base oil, and the most commonly used base oil is diesel (Number 0 diesel is commonly used in my country). In oil-based drilling mud, the volume concentration of diesel as an additive often exceeds 50%, and water is uniformly dispersed in diesel as an essential component, and its water content is generally 10-60%. Drill cuttings produced durin...

AI Technical Summary

Problems solved by technology

The comprehensive oil content of drill cuttings treated by drying machine is higher than 4.8%, and cannot be discharged directly; the oil mass fraction of drill cuttings treated by thermal fractionation is lower than 1%, but this method has complicated equipment and harsh operating conditions, and many It is used in professional treatment plants; the cuttings reinjection method is to grind and sieve the cuttings and add an appropriate amount of seawater and thickening agent to select a suitable formation for injection. This technology is thoroughly processed, but the cost is very high, often exceeding the well team's Affordability

Hot water washing method (also known as thermal desorption method) has high oil washing efficiency, but the equipment occupies a large area, consumes a lot of water, and will cause secondary pollution

[0004] With the great development of offshore oil drilling and production, the problem of oil pollution in the ocean is becoming more and more serious. The pretreatment of drilling cuttings on offshore platforms often uses a centrifuge for preliminary drying. The screen cylinder and drum of this centrifugal dryer are severely worn during operation , the service life is short, and the dryness of the discharged drill cuttings is not high enough, so there is an urgent need for an oil-based drill cuttings harmless treatment device with a compact structure and easy operation, so that the drill cuttings can be directly discharged into the sea after treatment, meeting the needs of deep sea or open sea drilling needs

Images