Tunneling Bentonite Slurry Recycling Decanter Centrifuge LW400 High G Force Mud Purification System

Shield tunneling and horizontal directional drilling projects rely on bentonite slurry to stabilize the face and carry cuttings away, and that slurry must be cleaned and recycled continuously to keep the operation economical. HUADING LW400 tunneling bentonite slurry recycling decanter centrifuge separator removes fine silt and clay particles that hydrocyclone systems cannot eliminate, preventing the buildup of fines that degrades mud density, viscosity and filter cake quality. With a 400 mm bowl developing 3950 g of centrifugal force, the machine polishes the recirculated slurry to the quality required for the next ring of tunneling, dramatically reducing fresh bentonite consumption and waste slurry disposal volume.

The decanter receives the underflow from the desander and desilter stages, or directly treats the mud return line in smaller drives. Cleaned slurry discharges from the centrate outlet and returns to the mud tank, while the separated silt cake is conveyed out for disposal or further treatment. The automatic control system matches the differential speed to the incoming solids load, keeping the separation sharp even when the cutter head encounters changing geology. Skid mounted and containerized versions are available so the unit can be lifted into position alongside the slurry treatment plant and commissioned within a day.

• Fine particle removal: The high g force captures silt and clay down to 2 microns, holding mud density and rheology within specification for consistent face support.
• Bentonite savings: Recycling purified slurry cuts fresh bentonite purchases by up to ninety percent on long tunnel drives, recovering the machine cost within the first project.
• Automatic operation: The PLC regulates feed rate, bowl speed and differential speed, so the plant runs unattended through day and night shifts.
• Compact modular design: The skid mounted package integrates with existing hydrocyclone plants and fits into standard site containers for rapid relocation between projects.
• Wear protected internals: Tungsten carbide tiles resist abrasion from sand and rock flour, keeping maintenance intervals long in the toughest ground conditions.
• Low polymer dependence: Mechanical separation removes fines without heavy flocculant use, keeping operating cost low and simplifying slurry chemistry control.
• Environmental compliance: Reduced waste slurry volume lowers disposal cost and supports compliance with strict site discharge regulations in urban tunneling projects.

The LW400 supports slurry shield TBMs in metro, highway, sewer and water tunnel projects, and cleans bentonite mud for pipe jacking and horizontal directional drilling operations. The same machine treats drilling mud for bored piles, diaphragm walls and mineral exploration rigs, and dewaters the waste slurry before off site disposal. In tunneling fleets, the decanter is often shared between multiple drives, moving from site to site on a container skid. Contractors benefit from stable, high quality mud that improves face pressure control, reduces cutter wear and minimizes the risk of clogging, while the environment team gains a defendable, low volume waste stream.

HUADING delivers the LW400 as a complete slurry treatment module with feed pump, control panel and interconnecting pipework pre assembled on the skid. Every machine is dynamically balanced, hydro tested and run under load in the factory, with the test certificate included in the handover file. For tunneling projects the unit can be built inside a standard 20 foot container with integrated tanks, lighting and ventilation, ready to connect to site power and water. Documentation covers the layout drawing, foundation and lifting plan, electrical schematic, operation manual and spare parts catalog. The twelve month warranty is backed by HUADING service engineers who support commissioning and provide remote diagnostics during the first tunnel drive.