Tailings Filtration for Dry Stacking and Paste Backfill

Set the filter cake acceptance criteria at the handover point. Dry stacking needs a cake that can be transferred and handled along the chosen route. Paste backfill needs a feed that the paste plant can meter and mix within its operating range.

Pressure filtration is one route to evaluate against the actual cake handover requirements.

Jump to Dry stacking ou Paste backfill.

Cake for Dry Stacking

Confirm discharge height, chute or conveyor geometry, stickiness and expected moisture variation. If cake is trucked or held in a buffer, test how it loads, breaks up and unloads. Agree the acceptance limits with the site’s tailings and geotechnical teams. Cake transfer and storage facility design are separate project responsibilities.

Cake for Paste Backfill

Agree the filter-to-mixer interface with the paste plant team. Confirm the feed solids range, buffer and metering arrangement, and how variable cake moisture changes water addition and the approved mix. The paste plant team should set and verify the requirements for mixing, transport and backfill performance.

Compare Equipment at the Handover

Use representative samples to compare dry-solids output, cake moisture distribution and release. Check cake behaviour against the planned receiving equipment, and confirm the filtrate return route separately. If ceramic disk filtration cannot consistently meet the cake handover requirements on representative feed, compare a filtro prensa de membrana on the same material.

Compare the Two Cake Handover Requirements

What the filtration package must hand over and who defines the target
Decisão	Dry stacking	Paste backfill
Where to check the cake	At the filter discharge and at the point where the conveyor, truck or placement operation receives it.	At the filter discharge and the inlet to the buffer, feeder or mixer.
How to set moisture criteria	Use the site team’s handling and geotechnical criteria. Check the acceptable range across the placement and compaction plan.	Use the paste plant’s allowable feed solids and mix design. Check how cake variability changes water addition and feeding.
What to observe	Release, adhesion at transfers, breakup, loading and unloading, and changes between discharge and placement.	Consistent discharge, bridging or lumps in the buffer, feed rate to the mixer and response to short interruptions.
When to revisit the filter route	If stable vacuum operation cannot achieve the agreed handling window at useful rate, compare pressure filtration.	If cake meets mix criteria but the feed is irregular, check buffer and metering. If cake condition is outside the usable range, compare settings or another route.

Compare both the average and the spread of wet-basis moisture across repeated runs. A shift average can meet the target even when some cakes stick or fail to transfer. Document where the sample was taken and include what happened at the chute or buffer. With a batch press, verify whether the receiving equipment can absorb the short discharge peak. A continuous filter also needs a plan for interruptions and cleaning.

PORVOO can configure the discharge height and review chute, buffer and controls interfaces against the agreed plant layout. Final stack design and placement criteria come from the site’s geotechnical team. Final paste mix, pumping and underground placement criteria come from the paste plant and mine teams. See the Filtered Stacked Tailings: A Guide for Study Managers, published by the Tailings Management Consortium formed by BHP and Rio Tinto, for dry-stack study context. See BOKELA’s Sasa example for the supplier’s published equipment scope for a mine backfill project.