Big Bowl Dewatering Centrifuges for TBM Mud Treatment to Singapore

Tunnel boring machine is an important machine in the city construction project like subway and pipe laying. In order to bring out the cutting and lubricate the drill bit of the tunneling machine, the operators need to add large quantity water or drilling fluids into the drilling well. For cost saving, the operators also have to think about reusing of the drilling fluids. Mud recycling equipment is mainly used to recycle the drilling fluids and remove the cuttings. Shale shaker, de-sander and de-silter could respectively separate the coarse solids, sand and silt. For fine solids, the decanter centrifuge would be needed.

After several time recycling, the specific gravity of the drilling fluids would be higher and higher due to the built up of ultrafine solids that even cannot be removed out by using only the centrifuge unit. Operators need to add chemicals into the drilling fluids and then do the dewatering process.  Dewatering centrifugepackage includes 2 parts: chemical dosing system and big bowl decanter centrifuge unit. The units ready for shipping to Singapore is designed containerized with both the centrifuge and dosing unit are put into the 20 feed container for easy transportation and jobsite safety purpose.

GN’sdosing system is consisting of powder feeding hopper, powder transferring screw, mixing tank and discharge pump. The screw is PLC for accurate metering of the powder. Mixing tank is divided into 3 departments for flocculation powder mixing, curing and storing. The mixing procedure is also PLC for automatic convenience. Before the drilling fluids fed into the decanter centrifuge, the flocculation agent is firstly mixed into the fluids to gather the ultrafine solids. Thus the decanter centrifuge would remove the floccule from the drilling fluids.

 

Removing the ultrafine solids from the drilling fluids greatly reduces the consumption of water and increase the drilling efficiency. The dewatering centrifuge package can also be used inoil sludge treatment project for oil recovery.

GN Mud Cleaning Equipment in The States for Construction Mud Treatment

These days, one of GN’s engineers is busy on commissioning of the mud cleaning equipment sent to the site where a client from The States want to use these equipment to clean the waste mud produced in construction project. So far, all the equipment have been well connected, next, GN’s engineer will help to test running of the equipment and train client’s operator how to use GN machine. This client totally order 2 set mud cleaning system from GN, GN hopes the performance of the machine would satisfy client and brought profit for client as soon as possible. The ordered mud cleaning system is consist of several separation modules and related auxiliary equipment, below is a brief introduction on the system.

  1. Trash collecting hopper – construction waste is delivered to site and then firstly mixed by water to make the waste flowable. At the bottom of the hopper, there are valves for discharge the waste onto a coarse screen for large size particles. This hopper is installed underground for easy waste discharge from the truck.  2. Coarse screen — the coarse Screen under the hopper would remove the trash like debris, cans, metals etc. The collecting tank under the coarse screen is used for temporally storing the liquid that would be treated further by the fine screen.  3.High G drying shaker — On one mud tank, GN’s high G force drying shaker is fixed on the first compartment of the tank. The liquid pumped from the tank beneath the coarse screen will be separated again by the drying shaker for fine particles removing and water recovering. For better performance, GN’s shaker is fixed with composite frame screen panel and oil resistance rubber seal strip. This extends the continuous working period and reduces the maintenance frequency
  2. De-silter unit — The de-silter is assembled equipment by cyclone frame and under drying shaker. The cyclone unit could reduce the cut point down to about 20 microns for much finer solids separation. The under drying shaker is same model with the high G force shaker for maintenance convenience.  5. Big bowldecanter centrifuge — the decanter centrifuge is provided with telescopic skid. The slurry treated by the cyclone unit would be fed to the centrifuge for polishing. The ultrafine solids cannot be removed even by high speed decanter centrifuge. Thus, GN equipped dosing system that is used for mixing the flocculation agent. By adding the flocculation agent, the ultrafine solid particles would be gathered and separated by the centrifuge unit

All equipment is provided modularly for easy connection and installation. Per specified request, clients could choose all or several of the modules. For further information on this project, please pay constant concern on GN Solids Control.

GN Decanter Centrifuge Working in Canada for Oil Sludge Treatment

Couple months ago, one client ordered decanter centrifuge and centrifugal pumps from GN solids on their jobsite in Canada for oil sludge treatment. Oil sludge would come from the drilling site oily waste cuttings, oil storage tank bottom sedimentation flushing slurry and refinery plant oily waste.
GN has decanter centrifuge designed especially for the oil industry. After few years’ development, the centrifuge unit was approved qualified in solids control fine solids separation, drilling fluids recycling and oil recovery from waste oily sludge.

Before the decanter centrifuge, the client already had the shaker unit for coarse solids separation. This thick oily sludge would be mixed with chemicals firstly in a steel tank for demulsification and viscosity reducing. But only using the shaker unit cannot remove the fine solids in the slurry. After sufficient communication and factory visiting, the client fully know the capability about GN’s decanter centrifuge, finally they order two units from GN.
One of the two centrifuges is 14 inch with max speed up to 3900RPM. This is GN’s most popular model for oil industry. With a high speed, this unit can remove the ultrafine solids from the slurry if adding flocculation agent. The other unit ordered is GN’s big bowl centrifuge with 22 inch diameter rotation bowl; this unit is used to remove the large content solids as its high flow capacity.

Shortly before, GN upgraded the centrifuge bowl material by using stainless steel of 2304 with much better features on corrosion resistance. Centrifugal casting technology makes the bowl body with better balance performance. Both of the units are equipped with VFD control panel for various working condition and client’s multiple purpose. GN is also able to provide the skid for centrifuge to put on for a convenient performance.

GN always makes inventory of decanter centrifuge in case of any urgent request from clients. Welcome to GN for business negotiation and factory capacity inspection.control, and now the centrifuge unit are working