Tunnel water is dominated by fine silt and rock flour that settles too slowly for tanks alone. Coagulation and high-rate lamella clarification clear it to consent in a compact footprint.
The parent application across the whole drive.
Sediment and suspended-solids removal for tunnel water.
The high-rate clarification technology in depth.
Flow estimation, treatment-train sizing and discharge compliance.
The suspended load in tunnel water is mostly fine silt and colloidal rock flour generated by excavation, probe drilling and grouting. Left to plain settlement it is far too slow, so lagoons silt up and carry over. Coagulation destabilises the colloids into settleable floc, and high-rate lamella clarification then clears the full flow in a fraction of the area a tank would need — the practical way to hold tight TSS limits at a constrained portal.
Compact High-Rate Solids Removal
We pair charge-neutralising coagulation and polymer flocculation with inclined-plate lamella clarifiers to achieve a large effective settling area in a small footprint. Dosing is jar-test calibrated to the actual water and trimmed automatically as the load changes through the drive. The result is a clarifier that turns thousands of mg/L of suspended silt into a compliant discharge, with thickened sludge sent for dewatering.
Inclined plates give a large settling area in a compact, portal-sized unit.
Jar-test-set coagulant and polymer grow settleable floc from rock flour.
Settled solids thickened for economical dewatering and disposal.
Reliable reduction to consent even at high, variable solids loads.
The Solids Problem
Tunnel fines are colloidal and slow, so removing them needs chemistry, not just retention time.
Sub-micron and low-micron fines stay suspended without coagulation.
High-rate clarification clears the flow where lagoons will not fit.
Solids swing with the ground, so dosing must adapt.
From Raw Ingress to Clear Water
Polymer builds settleable, shear-resistant floc.
Thickened sludge sent for dewatering and disposal.
Plant We Build Into This Stage
Hydrocyclones strip abrasive excavation sand to protect pumps and media.
View EquipmentCoagulant and polymer dosing grows settleable floc from colloidal fines.
View EquipmentHigh-rate inclined-plate settlers cut suspended solids in a compact footprint.
View EquipmentMultimedia and pressure filters polish settled water to tight TSS limits.
View EquipmentSediment and suspended-solids removal for tunnel construction water.
View EquipmentPre-assembled, road-transportable treatment trains that relocate as work advances.
View EquipmentWhy Choose Reynolds & Bauhm
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