Contamination of drilling fluids with drilled cuttings is an unavoidable consequence of successful drilling operations. If the drilling fluid does not carry cuttings and cavings to the surface, the rig either is not “making hole” or soon will be stuck in the hole it is making. The drill cuttings that are separated from the drilling fluid on the surface by the soldis control equipment and some quantity of unrecoverable or economically unwanted drilling fluid are a major source of drilling waste. Drilled and formation solids that are sized smaller than can be removed by the solids control equipment are often reported as drill solids. Some quantitiy of drill solids will accumulate in the drilling fluid and must be removed by the solids control equipment or reduced in concentration by dilution.(source)
As the drill bit grinds rocks into drill cuttings, which become entrained in the mud flow and are carried to the surface. In order to get back in the mud to the recirculating mud system and to make the solids easier to handle, the solids must be separated from the mud. The first step in removing the cuttings from the mud involves circulating the mixture of mud and cuttings over vibrating screens called drying shakers.
The liquid mud passes through the screens and is recirculated back to the mud tanks from which mud is withdrawn for pumping downhole. The drill cuttings remain on top of the shale shaker screens; the vibratory action of the shakers moves the cuttings down the screen and off the end of the shakers to a point where they can be collected and stored in a tank or pit for further treatment or management.
Often two series of drying shakers are used. The original series (primary shakers) uses coarse screens to eliminate only the larger cuttings. The second series (secondary shakers) utilizes fine mesh screens to remove much smaller particles. In general, divided drill cuttings are coated with a large quantity of drilling mud roughly equal in volume to the cuttings.
Additional mechanical processing is often used in the mud pit system to further remove as many subtle solids as possible because these particles are inclined to interfere with drilling performance. This automated equipment usually is the property of one of three types: 1) hydrocyclone-type desilters and desanders, 2) mud cleaners (hydrocyclone discharging on a fine screened shaker), and 3) rotary bowl decanting centrifuges. Parted select solids are associated with the larger drill cuttings removed from the drying shakers.
If the solids collected by the shale shakers are still coated with so much mud that they are unsuitable for the next reuse or disposal step or if the used mud is valuable enough to collect as much of it as possible, the solids can be further treated with drying shakers utilizing high gravitational separation, vertical or horizontal rotary cuttings dryers, screw-type squeeze presses, or centrifuges. Cuttings dryers recover additional mud and produce dry, powdery cuttings.
All wells are drilled with generation of waste. Including drilling cuttings, waste water, spent drilling fluids, completion fluids, and filtration wastes and so on. With increasing legislation, public awareness and minimum operator environmental standards, the drilling waste management has increased in importance and no ranks in importance along side that of drilling fluids around the world.
- 1. In short, whole waste management is 4R’s processing
- 2. Recycle-Get the circulation loop
- 3. Recover-Help valuable material property recovery
- 4. Reduce-Cut down disposal and cost
- 5. Reuse-Reuse all reusable things
Drilling waste management systems are packages of different function for drilling waste management. Usually include high G drying shaker, auger feeder or screw conveyor, skid mounted cuttings dryer, and decanter centrifuge with telescopic skid, drilling cuttings tank or mud skips.
We are not a one size fits all treatment provider. To deliver totally customized waste management solutions, we leverage a broad portfolio of modular to deploy unique configurations tailored to your operating needs. From shakers to cuttings dryer, conveyance systems to thermal processing units, we have the right products to tackle any challenge, and the expertly trained personnel to implement the ideal solution.