Decanter centrifuge is a very normal machine for drilling mud treatment and for different type of waste management, like waste oil treatment, waste water treatment, and sand purification.
For different materials and different treating purpose, operator should choose the most suitable separation speed and G force in order to get the best performance and separation result. In this case, the variable frequency control of a decanter centrifuge is necessary.
GN Solids Control is a worldwide famous brand for drilling mud treatment and variable type waste management application. GN company offer different solutions to get the variable speed control of a centrifuge. Below is a general idea of the most normal 3 designs. Operator can compare and choose the most suitable design per his demands and the job site condition.

1) The most simply type variable speed control is Mechanical gearbox drive decanter centrifuge. For this kind of centrifuge, operator can get another fixed speed by using a different size of pulley. It is simply for operation and maintenance, and cost effective. And the mechanical gearbox drive centrifuge is especially suitable for high temperature like desert. If the jobsite is only need to use a few speeds, and it does not need to change speed frequently, the Mechanical gearbox drive variable speed decanter centrifuge is more suitable.

2) Another luxury variable speed centrifuge design is fully hydraulic drive centrifuge. The FHD centrifuge changes speed from the hydraulic drive system. The hydraulic drive system is suitable for high temperature area. But as you know, the hydraulic system itself is complex for operation and maintenance. And it is cost higher.
3) Another popular design of Variable frequency Drive (VFD) decanter centrifuge is changing speed through the speed of motor. They use frequency drive to change the speed of the motors to get different separation speed.

For more information of GN variable speed control decanter centrifuge technology, welcome you contact GN group with its 7 by 24 hours services center: This email address is being protected from spambots. You need JavaScript enabled to view it.

Chemical dosing system, is also named as dewatering unit, it is a mixing & storage system used to enhancing chemicals, or acid, alkali to other system or materials to reach a certain purpose. It is widely used in drilling waste management system, waste oil recovery system, waste water treatment system, soil clarification system, and other liquid treatment applications. Below are some of the applications of the dosing chemicals:

1) The chemical dosing system can be used to mix and prepare flocculent or polymers to remove the fine solids from waste oil or waste water. Mostly, the chemical dosing system is used together with decanter centrifuge separator. The separation point of centrifuge is 2 ~ 5 microns. Particles smaller than 2～ 5 microns is out of the range of centrifuge separation. After using flocculent, the ultra-fine particles and be flocculated to bigger size for centrifuge remove.

2) The chemical dosing system can be used to mixing and it can automatically add acid or alkali to liquid to reach the suitable PH degree. Mostly, the waste liquid is not neutral. It is either acidic or alkaline. During treatment, people should to make it to be neutral to reduce its harm to the environment. Based on the liquid situation, acid or alkali will be add to the system to neutralize the PH degree.

3) The chemical dosing system can be used to stock demulsifier for oily sludge separation system. After dosing the demulsifier, the viscosity of the oily sludge can be reduced, then it can be suitable for mechanical separation, like high G shaker, vertical cuttings dryer or decanter centrifuge. Decanter centrifuge is one of the most common equipment used together with chemical dosing system. According to different treating capacity requirement and the separating result, there are different sizes and different speed decanter centrifuge for option from world famous brand GN Solids Control. The bowl size varies from 9 inch, 14 inch, 18 inch, 22 inch and 30 inch.

Although it is national holiday in China, most people are enjoying the holidays. GN workshop people keep working every day to ensure clients with fast delivery products and systems. A full set 1500 GPM mud cleaning system was ready during the holiday. It will be dispatched to a Hong Kong client in the recent days.
It is a 1-tank mud purification cleaning system for 1500 GPM treating capacity. It is a 3 - phase separation mud system includes following items:

1) 3 ea solids control shale shaker are equipped on the system. The 3 shakers are 4-panel shale shaker, they can reach up 1500gpm mud treating capacity. It is for the 1rst stage separation.
2) After solids control shale shaker, it is a 3-in-1 mud cleaner for the 2nd and 3rd stage separation. The 3-in-1 mud cleaner is a combination of solids control shale shaker, desander and desilter.
The desilter cone assembly includes 3 ea 10 inch desander hydro cyclones. The desilter cone assembly includes 16 ea 4 inch desilter hydro cyclones. Both the desilter and desander cones are mounted on a shale shaker deck to work as a whole set cleaning machine.
3) All the separation shale shaker, desander desilter are mounted on an oilfield mud tank. And connected by pipelines.
4) The desander feeding pump and desilter feeding pump are mounted on the mud tank skid for small footprint and compact design.
Other attachment of the 1500GPM mud system: ladders, walkways, guardrails, pipelines, and electrical control systems.
Besides 1500GPM mud system, GN Solids Control offers other size mud purification and cleaning systems for different applications, like 150GPM – 200GPM small capacity mud cleaning system for water well drilling, 350~500GPM mud recycling system for HDD or CBM drilling, 800~1000 GPM mud purification system for HDD or piling projects, 1500GPM and 3000GPM for oil and gas drilling piling, CBM or micro tunneling projects.

Zero discharge mud system becomes more and more necessary for rig site. As the chemicals, heavy oil, and other kind of waste oil inside the drilling waste is hazardous to the environment. If the drilling waste has been discharged to the environment, the pollution cannot be recovered in short time or even for a very long time. Like in China and many countries, the governments have strict rules to control the drilling waste. Any oily waste or drilling waste cannot be on the ground. Unlike previous years, waste pit or mud pit is prohibited. GN Solids Control is a specialist for mud solids control and drilling waste management systems. GN specially designed zero discharge mud system is the ideal solution of drilling rig companies.
Recently, GN Solids Control will dispatch a complete set Zero discharge mud system for a rig fabrication company. Unlike normal drilling mud solids control system, the Zero discharge mud system is composed of a waste management system to recovery the drilling cuttings from the solids control shale shaker, desander and desilter. As the end user country accept Oil on cuttings (OOC) less than 5% for discharge. It is relative easy to reach.

Firstly, a set of vertical cuttings dryer is equipped for the 1500hp oil rigs. Why choose VG dryer rather than High G dryer? The reason is that, HG dryer is mainly used to treat the water based mud. It is not good at oil base mud. During drilling, in the first stage, they will use water base mud. When drill to a deep depth, they should change to oil base mud. GN patent design vertical cuttings dryer can be used for oil based mud, as well as water based mud. The rig site people do not need to change equipment when they change water base mud to oil base mud.

The cuttings after VG dryer is with OOC less than 5%. And it is dry enough for movement or discharge. The liquids recovered from VG dryer should be weighted for drilling. It should be treated by decanter centrifuge.

And then there is a high speed decanter centrifuge after the VG dryer to reduce the mud weight recovered from VG dryer. After remove some of the fine solids, the liquid mud can be back to rig mud system for drilling activities.