The coagulation and flocculation unit
(hereinafter referred to as the CFU) is intended to serve as the mobile
unit for centrifuges chemical improvement while the drilling mud cleaning
(extraction of “process water” non-combined solvent and removal of the “drilled
solids, solid and dissolved chemical reagent” solids from the mud by
preliminary chemical treatment of the mud and subsequent phase separation in
the centrifuge).
The GNDU2000 Series 20FT Dewatering Unit
provides a process of chemically enhanced configuration to remove the fine
solids less than 5 microns from the water based drilling fluids. As it known
that traditional solids control equipments like shale
shaker, desander,desilter,
and decanter
centrifuge will removes solids upper than 5 microns, for colloidal-size
particles which is less than 5 microns will build up in the drilling mud
system. To maintain the drilling mud properties, the operators have to dilute
the drilling fluids with water, this consumes more water and create more
drilling waste.
The mud to be cleaned is supplied from mud tanks to the
station by the centrifuge feeding pumps. The mixing device (mixer) is installed
inside the CFU. The CFU process equipment perform the mud mixing (dosing) with
chemical reagents in the mixer, then the mud is fed from the CFU to the
centrifuges. Centrate (process water) obtained in the centrifuges returns to
the CFU, and solids contained in the mud are removed by the centrifuge and
transferred into the sludge transporter. Centrate (water) is measured in the
CFU and if its parameters are satisfactory, the station pumps transfer it into
the tank (receiving tank) for the new mud mixing. If results are not
satisfactory, the centrate is pumped into the sludge transporter.
Mud and water are delivered and discharged
from the CFU by flexible hoses. The water supply system shall provide water
flow rate of approximately 3 m3/h for mixing in tanks. Centrate overflow,
centrate output to the storage vessels, centrate output to the control vessel,
water input/output, mud input to cleaning shall be designed with quick-release
couplings DN50 and shall be located in the same port on the CFU outer wall. The
port is covered by cover with padlock. 50 meters of flexible hoses are included
into the scope of delivery. Centrate is fed into the centrifuged water tank by
DN150 pipeline. Pipeline inside the CFU is made of constructional carbon steel.
Flange and gooseneck outside the CFU is made of constructional steel and
intended for centrate feeding from two centrifuges. The flexible hose DN150
delivers centrate. 10 meters of flexible hoses are included into the scope of
delivery. All quick-release couplings, flanges, bolts, goosenecks shall be
included into the scope of delivery also.