If you’ve run a slurry shield or TBM drive through an urban site, you already know the machine boring the tunnel is only half the operation. The other half is what happens to everything that comes back out of it.
Slurry shield TBMs use pressurized slurry to support the tunnel face and carry soil to the surface. But this raw slurry creates an immediate problem. It arrives continuously as a wet mix of soil, water, sand, and silt that you must treat instantly to keep the machine moving. Untreated slurry is expensive to store, costly to haul away as liquid waste, and often violates strict urban discharge laws.
KOSUN’s TBM Slurry Treatment System is built specifically to solve this. Here’s how it works.
The Core Problem: Slurry Isn’t One Material
Raw tunnel slurry blends water with sand, silt, and clay. Each particle size behaves differently during separation. If you treat it all as a single waste stream, you face two bad choices. You will either under-process it and get too much liquid waste, or over-engineer the system with slow, expensive, and oversized equipment.
The more effective approach is staged separation: pull out what’s easiest to separate first, then progressively target finer fractions in later stages. That’s the principle the system is built around.
How the System Works
Stage 1 — Desanding. The slurry first passes through cyclone desanders, which use centrifugal separation to strip out the coarsest sand fraction. This is the highest-volume, lowest-cost-per-ton separation stage, and getting it right early reduces the load on every stage downstream.
Stage 2 — Desilting. The remaining slurry moves through finer-cut cyclones and vibrating separation screens, targeting the silt-sized fraction. This stage is where particle-size cut points matter most — too coarse a cut and fines pass through untreated; too fine and you’re forcing volume through equipment that isn’t sized for it.
Stage 3 — Dewatering. What’s left is the fine fraction that resists simple mechanical separation — the material that, left untreated, is why tunnel slurry ends up hauled away as liquid waste. Dewatering equipment mechanically separates this fraction into a drier solid cake and clarified water, which is what makes dry transport possible instead of liquid hauling.
The output at the end of this line is two things a jobsite can actually use: graded solids dry enough to load and haul away, and water clean enough to be considered for on-site discharge or reuse — rather than one undifferentiated slurry stream that has to be trucked out as waste.
Before and After: What Staged Separation Actually Produces
It’s easier to see than to describe. Raw tunnel-face slurry comes off the drive as a heavy, saturated, reddish-brown mass — more mud than material, with no practical way to grade, transport, or reuse it in that state.
After it runs through the system, the same material separates into two distinct, usable outputs: a graded aggregate fraction dry enough to be conveyor-stacked and loaded for haul-away, and a water fraction clarified enough to be managed as a controlled discharge rather than a liquid waste stream. Same input. Two outputs a jobsite can actually work with.
Why Modularity Matters on a Tunnel Drive Site
Urban tunneling sites have very limited space. That is why projects choose TBM methods first.
These sites lack time and space for slow systems. You cannot wait weeks to plan and install equipment.
Our modular, skid-mounted system solves this problem. Desanding, desilting, and dewatering stages arrive as pre-engineered units.
We do not require field fabrication. You can assemble and run the system in days.
This speed saves you massive downtime costs.
Who This Is Built For
- Contractors running slurry shield or TBM drives on urban metro, utility tunnel, or underground infrastructure projects
- Project teams facing slurry disposal costs or hauling capacity limits that are constraining drive rate
- Sites operating under discharge permit conditions that raw, untreated slurry cannot meet
- Projects where mobilization speed and site footprint are as much a constraint as separation performance
Talk to KOSUN About Your Slurry Treatment Requirements
Every tunneling project has a different ground condition, drive rate, and site layout, and the right configuration of desanding, desilting, and dewatering capacity depends on all three. If you’re planning a shield or TBM drive and need to size a slurry treatment solution for it, get in touch — we’ll walk through your project specifics and put together a configuration that fits.