Vertical Mixing Systems

Download our Vertical Mixing Tank Product Information Sheet

Vertical mixing tank equipment at mine site for mixing and dosing reagents (lime in this application) for the treatment of Acid Mine Drainage (AMD), Acid Rock Drainage (ARD) or other water quality issues.

The Vertical Mixing Tank (VMT) Systems are portable mixing tanks with an internal mixer-baffle system specifically designed for the efficient mixing and dosing of a broad range of dry powdered reagents for the treatment of a range of water quality issues.

The tanks are sized to permit transportation on a flat-bed truck and to be loaded via conventional lifting equipment (e.g. excavator, forklift, backhoe etc.). This provides flexibility for sites that are difficult to access, and permits the system to be either used at a fixed location or moved to multiple locations.

The vertical paddle mixer and internal baffle arrangements are specifically designed for mixing dense solutions or uniform slurries ranging from 1 to 30 wt.% solids. It is suitable for mixing a range of dry powdered reagents including limestone, hydrated lime (calcium hydroxide) and quicklime (calcium oxide). This makes these systems ideal for a range of water treatment tasks including:

pH correction
Acid neutralisation (Acid Mine Drainage, Acid Sulfate Soils)
Turbidity reduction
Cyanide destruction
Lowering Total Dissolved Salts (TDS)
Toxic metal removal

The standard model features a 10,000 L epoxy painted mild steel tank with a reagent addition hatch, access ladder, handrails, lifting hooks, fluid inlets and outlets, dust exhaust vent and an integrated control panel for the mixer and pump(s). Slurry agitation is achieved via a variable low-speed 4-blade single paddle mixer. Insoluble grit can be periodically removed via a side access hatch.

Various configurations are available depending on site specific water treatment requirements. Optional components include: a bulk bag feed chute with bag breaker system, corrosion resistant feed water supply pump, integrated variable speed positive displacement dosing pump and programmable logic controller (PLC) available in a range of configurations for automated and/or remote operation.

The 10,000 L model is capable of mixing and dosing up to 6 tonnes per hour and can be optimised for rapid bulk dosing or fine dosing control.

The entire system can be powered by either mains or portable power.

Mode of Operation

Vertical mixing tank at mine site for mixing and dosing reagents.

Operation of the system is carried out by partially filling the slurry mixing tank with water and activating the internal mixer. Dry powdered reagent is then added to the tank via 25 kg or 1 tonne bulk bags. Treatment requirements will dictate the required reagent addition rates and slurry concentration. Depending on the reagent up to 10,000 litres of slurry or solution can be mixed and stored within the system ready for dosing.

As an example, for acid control, up to 3 tonnes of hydrated lime powder can be added to the 10,000 litre mixing tank to produce a slurry of 20-30 wt. % solids.

Reagent mixtures often need to be periodically or semi-continuously agitated to prevent setting of solids. The reagent mixture can be distributed by gravity feed or with a pump-based dispersion system. Depending on site treatment requirements, dosing rates can be adjusted to cater for bulk/rapid or fine dosing tasks.

Key Attributes

Transportable – can be used at multiple locations on a single site OR across several sites.
Simple operation and control systems.
Flexible dispensing options for sites with difficult or remote access.
Suitable for most dry powdered reagents including lime based reagents.
High reagent throughput – capable of mixing and dosing up to 6 tonnes of dry powdered reagent per hour.
Integrated control panel with standard programmable logic controller (PLC)
Three phase mains or portable power options
Optional fully automated dosing and monitoring systems
Ideal for emergency response dosing and remote sites.
Suitable as a supplemental dosing system and for back-up dosing during scheduled and unscheduled fixed plant maintenance.
Low operational and maintenance costs
Suitable for correcting water quality issues in dams, pit lakes, tailings facilities, process ponds….etc