Dual Fuse Equipment designed to complement Traditional Solid Control Systems.
Solids control is a technique deployed on Oil Rigs drilling rigs to separate the solids crushed by the drill bits from recyclable drilling fluids after the semi-solid emulsion is brought to the well surface. The removal of solids from the circulation system leaves the Rig with reusable drilling fluids in the wells. The ultimate goal of Solids Control is to prolong the drilling fluid life cycle whilst at the same time reducing waste. The removal of solids additionally reduces the risk of downhole related problems resulting from solid contents in the drilling fluid.
Dual Fuse Equipment and Solid Control Technology
Provided optimal Solids Control technology is deployed, this can help to reduce the complexity of drilling fluid clean up and maintenance and disposal cost. At its core most Solids Control systems are divided into five stages:
Shale Shaker
The Shale Shaker separates drilling fluids from larger type solids referred to as Drill Cuttings.
The basic design consists of large, flat sheets of wire mesh screens or sieves of various mesh sizes that shake or vibrate the drill cuttings across and off of the screens as the drilling fluid flows through them and back into the drilling fluid processing system, often called the mud system. This separates the drill cuttings, often called solids from the drilling fluid so that it can be recirculated back down the well bore. In oilfield industry, the linear motion type shale shakers is the gold standard for use in drilling mud solids control systems, in oil and gas well drilling.
Mud Tank
All these stages are carried out on the top of the mud tank. After solids are separated, the clean mud can once again be used to pump into the wellbore.
Vacuum Degasser
Vacuum degasser is one of the main equipment in solids control system to separate gas from drilling mud . And the degasser normally sits beside Shale Shaker and before Desander to protect centrifugal pumps. An efficient degasser is very important to safe and productive drilling operations. As the composition of the gas encountered, the present gas mud will decrease efficiencies in the solids control pumps. So we can say vacuum degasser is to keep the pumps operating properly.
Desilter and Desander
Desanders and desilters are solid control equipment with a set of hydro-cyclones that separate sand and silt from the drilling fluids in drilling rigs. Desanders are installed on top of the mud tank following the shale shaker and the degasser, but before the Desilter. Desander removes the abrasive solids from the drilling fluids which cannot be removed by shakers. A centrifugal pump is used to pump the drilling fluids from mud tank into the set of hydro-cyclones. Desanders have no moving parts. The larger the internal diameter of the Desander is, the greater the amount of drilling fluids it is able to process and the larger the size of the solids removed.
Centrifuge
Centrifuges are another essential part of any effective solids control system. They have a great advantage of achieving extremely fine cut points. The rotating speed is transformed into centrifugal force inside the rotating assembly to accelerate particle settling. Ultimately is a settling pit which allows for rapid settling of solids under controlled conditions.
Which role can the Dual Fuse equipment play parallel to Solid Control Equipment?
The Dual Fuse equipment adds a new dimension to Solid Control by adding collection, storage and disposal of Drill Cuttings. It collects the Drill Cuttings from the Shale Shaker and deposit these into a Drill Cuttings Blower which pneumatically conveys the Drill Cuttings through a pipe line circuitry to available Dual Fuse Tanks. From there the Drillings are pneumatically conveyed to further Dual Fuse tanks on the PSV (Platform Supply Vessel) or alternatively into skips. The Drill cuttings in Dual Fuse tanks or skips have to be disposed off on shore to be treated by Drilling waste treatment companies.
How this is done depends on the operational set up of the Dual Fuse tanks on the PSV Platform Supply Vessel. There are two options:
Dual Fuse tanks on PSV Platform Supply Vessel are positioned horizontally. Dual Fuse tanks can only be discharged when they stand vertically. Therefore, when tanks are positioned horizontally this means that the PSV Platform Supply Vessel has to berth where the Dual Fuse tanks will be offloaded onto container haulage trucks with prime mover (tractor) and 20ft iso container trailer. From there the Dual Fuse tanks have to be trucked to a Drill cuttings waste treatment facility for off loading. As Dual Fuse tanks can only be off loaded when standing upright, upon arrival the Dual Fuse tanks are off loaded and rotated deploying the DNV certified slings hooked on the lifting lugs mounted on the Dual Fuse tanks and discharged in the vertical plane ready for offloading.
Dual Fuse tanks on PSV Platform Supply Vessel are positioned vertically. This option is used when a land bulk storage facility for drill cuttings is available. In this case the PSV does not need to berth. Under this scenario the Drill cuttings are pneumatically conveyed from the Dual Fuse tanks into the land bulk storage facility much like Drill cuttings are conveyed from Oil Rig to PSV Platform Supply Vessel.