Tag Archives: desilter
Solid control desander and desilter from China Manufacturer
DC Solids Control provides a large number of solid control system and waste treatment system products to customers worldwide every year.
DC Solids Control desander is mainly used to remove drilling cuttings larger than 55 microns in drilling fluid. The drilling fluid purification sand remover is mainly composed of underflow screen and 10 inch sand removing cyclone. Under normal circumstances, the centrifugal pump is used to feed the desander.
The cyclone uses a centrifugal pump to pump the mud into the swirl cone at high speed, and centrifugally separates the mud under the action of centrifugal force. After centrifugal separation, the lighter mud flows out of the cyclone outlet. The mud with high solid phase is ejected through the drip nozzle, and further sieved and separated through the underflow screen.
The structural principles of DC Solids Control Desilter and Desander are similar. The only difference is that the cyclone used in the desilter is a 4-inch cyclone. Generally, the number of desilting cyclones is an even number. Desilter is mainly used to remove solid cuttings larger than 25 microns in drilling fluid.
Besides above the separated desander and desilter. DC Solids Control also provides ‘3 in 1’ treating unit which is ‘DC Mud Cleaner’, it’s composed by 10 inch cyclone, 4 inch cyclone and bottom shale shaker. Every year. Welcome to connect with us if you need any solids control equipment.
Testing desander unit used for piling field in DC Machinery workshop
Desander is an common equipment of piling field which mainly separate out the 45-75um solid phase. Last week, the desander unit manufactured for Singapore clients tested in DC machinery workshop.
Structure of piling desander
Desander is the combination of hydrocyclone and shale shaker. The main body can be separated into two parts, the above part is the hydrocyclone and the bottom is the circular shale shaker. The vibration exciter is driven by a vibration motor to keep the whole screen box vibrate with a forward circular track.
Piling Desander Features
Desander Options with shaker and without shaker for flexible applicaiton.
Desander Cyclone PU material with better Abrasion resistance
No under shaker design structure compact and assembly flexible
Mini desander cleaner with shaker for both weighted / unweighted mud in various drilling
Desander is placed after shakers and degasser but before desilter. Different from the Shale Shaker separating solids by screen. If you want to learn more about it, please contact us.
Comparative Operation of Desanders and Desilters
The role of desanders is to reduce loading downstream on desilters. Installing a desander ahead of the desilter relieves a significant amount of solids loading on the desilter and improves desilter efficiency. High rates of penetration, especially in unconsolidated surface hole, where the largest-diameter bits are used, results in generating larger concentrations of drilled solids. This may place desilters in rope discharge. For this reason, desanders, which have greater volumetric capacity and can make separations of coarser drilled solids, are placed upstream of desilters.
Desanders remove a higher mass (i.e., coarser drilled solids) during periods of high solids loading. Desilters can then efficiently process the reduced solids-content overflow of the desanders. If the drill rate is slow, generating only a few hundred pounds per hour of drilled solids, the desander may be turned off and the desilter used to process the entire circulating system.
Desilters should be used on all unweighted, water-base mud. These units are not used on weighted muds because they discard an appreciable amount of barite. Most barite particles fall within the silt-size range. Desilter operation is important for all unweighted fluids; however, in oilbase muds with high viscosity (as found in deepwater drilling), the apex discharge may be centrifuged for oil-phase salvage.
History of drilling fluid mud cleaner
Mud cleaner are a combination of hydrocyclones mounted above shaker screens with small opennings.
When mud cleaners were invented in 1971, main shale shakers on drilling rigs were eigher unbalanced elliptical or circular motion machines. The first screen at that time could separate solids only larger than about 177 microns from a normal drilling-rig circulating rate.
The first mud cleaner was a combination of two 12 inch diameter and twenty 4 inch hydrocyclones mounted above a specially built, 5-foot-diameter, stainless steel, round swaco shaker. Even though the mud cleaner was invented for use with a weighted drilling fluid, the first application was on a well drilled using one of the first unweighted, potassium chloride drilling fluids, in a shallow, 2200-foot research well near Houston, Texas, in 1971.
The second mud cleaner was a bank of twenty 4-inch pioneer hydrocyclones mounted above another specially built 4-foot diameter, double deck, staubless steel, round Swaco shaker. The screens could be arranged in parallel or in series to process the underflow from the cones. This unit was placed on an exploration well in South Louisiana. A gas-bearing formation at about 11.000 feet contained an 11.0-ppg pore pressure.
When the mud cleaner was first introduced, many would try to decide whether to use a mud cleaner or a centrifuge. The problem with this decision is that mud cleaners don’t compete with centrifuges in solids removal. In weighted drilling fluids, mud cleaners are designed to remove drilled solids larger than barite( larger than 74microns). Centrifuges remove solids mostly smaller than most barite(less than 5 to 7 microns).
USES OF MUD CLEANERS
The principal use of mud cleaners has always been the removal of drilled solids larger than barite. Sufficient drilling fluid bypasses shale shakers so that even with 74-micron (API 200) screens on the shakers, many drilled solids are removed from a weighted drilling fluid. When linear motion shakers permitted API 200 screens to process all of the rig flow, mud cleaner usage declined rapidly. However, whenever a mud cleaner was used downstream, the screens were loaded with solids.
A secondary use of mud cleaners is the removal of drilled solids from unweighted drilling fluids with a very expensive liquid phase—such as the initial application with the potassium chloride drilling fluid. In this case, the underflow from desilters is screened to remove solids larger than the screen opening. Solids and liquids pass through the screen and remain in the system. This is beneficial for non-aqueous drilling fluids as well as saline water–base drilling fluids.
In unweighted drilling fluids, the desilter underflow could be directed to a holding tank. A centrifuge could separate the larger solids for discard and return the smaller solids and most of the liquid phase to the drilling-fluid system. This method is easy to apply if a centrifuge is already available on a drilling rig. More drilled solids would be rejected by the centrifuge than by the mud cleaner screen; however, renting a centrifuge for this purpose may be more expensive. Both techniques have been used extensively in the field.
4 inch Drilling Fluid Desilter in Stock for Sale
Desilter cones are manufactured in a variety of dimensions, ranging from 2 to 6 inches, and make separations of drilled solids in the 15-to-44-micron range. They will also separate barite particles in the 8-to-25-micron range. Desilters are installed downstream from the shale shaker, sand trap, vacuum degasser, and desander.
Desilter cones differ from desander cones only in dimensions and operate on exactly the same principles. Common desilter cone sizes are between 2 to 5 inches. A centrifugal pump should be dedicated to provide fluid to the desilter manifold only. Setting up a centrifugal pump to run multiple pieces of equipment is not a good idea, as doing so requires compromises in performance and opportunities for incorrect operation.
These units make the finest particle-size separations of any full-flow solids-control equipment-down to 12 microns of drilled solid. The desilter, therefore, is an important device for reducing average particle size and reducing drilled solids.
Desilter suction is also taken from the immediate upstream tank, usually the desander discharge tank. Desilter suction and discharge tanks are, again, equalized through a valve, or an opening located on the bottom of each tank.
The maximum (max) gpm will be the maximum flow rate expected, not the backflow, as there will be times when the unit will not be operating and the total rig flow rate will have to pass through the valve or opening. Suction should not be taken from the tank into which chemicals and other materials (barite and bentonite) are added because valuable treating materials may be lost.
A 4 inch desilter cone is able to remove solids at a flow rate of 44-66 gallons per min (gpm). The above picture is a desilter (10×4’’ cones, model CNQ100) newly manufactured by Dachuan Solids Control, so the total handling capacity can reach 440-660 gpm.
How to Install and Maintain the Desilter
Install and maintain the desilter is important for drilling works, as a part of solids control.
Steps
- Install and debug: The slurry cleaner is mainly consisting of vibrating sieve, distributary manifold and swirled, etc. having the slurry exit of the sand pump and pipe elbow of liquid going-in of slurry cleaner connected with 6″rubber hose, pipe elbow of liquid going-in able to circumrotate round the vertical axial line with arbitrary angle. The both ends of overflow pipe of slurry cleaner are symmetrical, which can be used as overflow end for equipping 8″ rubber hose for conduction into another tank of drilling fluid.
- Position the angle. Under ideal working state the spouting angle at the bottom will be 20°～30°.
- Keep up maintenance. After the equipment has run up to 4000hours, the wearing parts including cone-shaped canister and spiral case, etc. should be checked or replaced.
Don’t start it working right away. No load running should be going for 5~15 minutes after every halt of pump running, with screen cloth cleanly washed in clear water. And it is especially to do so when slurry having big viscosity to be processed with close-mesh screen for processing effect will be impacted because the meshes are blocked by sticky substance and silver sand.
Drilling Mud Cleaner from DC Machinery
Compared with the traditional desander and desilter, mud cleaner is the upgrade product. It belongs the second or third level solids control equipment in the drilling fluid solids control systems, it is the complex of hydrocyclone desander, hydrocyclone desilter and the shale shaker.
The structure of mud cleaner include desander, desilter, pressure pump, swirler, bottom flow slot, drilling fluid shale shaker, support and base. the characteristic is there is a control butterfly valve between the main inlet tube and drainpipe of desander and desilter, on the base there is a chute, the shale shaker is located on the chute. In the swirler, there are automatic sand blocking prevention equipment and bottom flow port regulation equipment.
Features & Benefits of DC Machinery‘s Mud Cleaner:
1 Polyurethane (PU) Material for desander and desilter cones.
2 Desander cones can be installed between one and three 10”desander cones, each cone can process 500GPM and makes a separation between 40 and 100 microns.
3 Desilter cones can be installed between eight and twenty 4”or 5”desilter cones,each cone can process 80 GPM, and makes a separation between 15 and 75 microns.
4 Mechanical Deck Adjustable while operation for reliable performance.
5 Compact design with small footprint, with top feed and wire feed two option.
6 Hook-strip shaker screen for fast screens changing with PWP and PMD screens.
Application of desander and desilter
The cut point of 10 in or 12 in desander is 40 ~ 45 um and that of 4 in and 5 in desilters 20 ~ 25um. Since desanders and desilters would discard large amount of barite along with the drilled solids in a weighted mud, therefore they are usually used only with unweighted mud.2 in desilters can be optionally used for removing even finer particles (7 ~ 10um) of the underflow of the upstream desilters or mud cleaner.
Number of hydrocyclones: the number of desanders arranged in a set for a rig is determined in the way that the capacity processed by the defined number of hydrocyclones of a set of desanders must be equal to 125 % of the maximum rig circulating rate or more. A number of hydrocyclones in a set of desilters must process 150 % of the rig maximum circulating rate.
Factors influencing hydrocyclone performance:
(1) Mud density.
(2) Solid content of the underflow of the preceding equipment or solid content of the mud that gets into the inlet of this unit.
(3) Mud viscosity.
(4) Feed pressure.
(5) Feed flow rate.
(6) Apex size.
Arrangement of Solids Control Equipment
The following pictures show the recommended arrangements of the solids control equipment for unweighted and weighted mud systems. In general, the various pieces of equipment are arranged in decreasing order of their cut points as the mud proceeds downstream from the flowline.
Any dilution water used should be introduced ahead of the solids- removal devices in order to improve their separation efficiency. Additions of all other mud materials should be made downstream from the last solids-removal device.
The feed and discharge of each device should be separated so that newly processed mud is not fed back to the device. Preferably, the feed and discharge should be in alternate pits. The discharge end of the overflow pipe from a desilter or desander should be above the mud level. If it is not, the separation efficiency will be reduced and mud can siphon back through the cones and out the underflow when the pump is shut down.