High Rate Thickeners (HRT)

Delkor is a leading supplier of High Rate and conventional Thickeners with over 250 installations all over the world.

Thickeners are used in many types of process circuits for solid-liquid separation at very high rates. These are highly effective in coal refuse thickening, gold recovery, CCD Circuits, copper leaching, molybdenum processing and other mining and chemical processes. Separation is effected rapidly on account of system hydraulics, which can be in excess of twenty times the hydraulics of conventional thickeners.

Delkor’s HRT offers significant advantages over conventional thickeners by using the fluidized sludge bed principle for solids separation. The HRT injects the feed near the bottom of the unit. The feed solids form a fluid bed above the feed injection point and the feed slurry is then filtered as it flows upwards through the fluid bed.

High Rate Thickeners have a deep feed well with a Deflector Plate, feeding into the Hindered Settling Zone, just above the Compaction Zone, eliminating the Free Settling Zone present in Conventional Thickeners and reduces Thickener size. The liquid filters up through the Mud Bed to the overflow, resulting in high overflow clarity.

A combination of innovative design and associated hydraulic efficiency helps reduce plant area considerably, even making indoor installations possible and also substantially reducing capital and installation costs.

Advantages

Conventional Thickeners

Conventional Thickeners have a large Free Settling Zone where solids settle through the liquid until they reach a Hindered Settling Zone. Here the solids crowd and settling is hindered. Below this, further compaction occurs from solids settling above, and from the squeezing action of rakes. The Free Settling Zone occupies the majority of the Thickener volume.

Applications

	Grind Thickening
	Concentrate
	Tailings
	Leach thickening
	CCD Circuits

Advantages

Conventional Clarifiers

Delkor manufactures, supplies steel and installs clarifiers for use in primary settling or secondary settling. With a range of up to 80 feet in diameter, these clarifiers are partially pre-assembled in the factory and the components are welded together on site.

Conventional Circular Clarifier with Central drive is provided with a central rake drive mechanism supported on a bridge which can either be half or full bridge, based on the clarifier tank size or plant requirements. This is one of the most basic units and is available in sizes of 60 m diameter & above.

Conventional Circular Clarifier with peripheral drive is provided with a rake drive which travels on the peripheral tank wall driving the bridge which is pivoted at the centre and is carried on an adequately sized bearing supported on the centre pier. The rake arm is attached to the moving bridge which either can be half or full bridge based on the process requirement mostly dictated by the sludge generation. In view of the moving bridge, the power supply is provided through a slip ring assembly mounted at the centre of the bridge sourcing power supply by the electrical cable laid through the centre pier.

Delkor Clarifiers use the filtering action of the mud bed to produce overflows that are very low in suspended solids (with 20-50 ppm clarity). Efficient de-aeration, flocculation and mixing can be achieved in the external de-aerator / mixing vessel.

Underground Mine Water Settlers can be supplied with steel tanks or installed in conical excavations. Capacity of the Delkor Settler is 14 to 30 m3 /m2h. This means significantly smaller excavations are required when compared to conventional settlers.

The Delkor Settler uses a mud rake to eliminate blockages in the discharge cone. Many Delkor Settlers have flat bottoms, resulting in reduced excavation costs. Conversion of existing Settlers results in large improvement in performance and capacity.

A variety of options can be provided with flexibility in relation to size, flow rates, design options and site requirements.

Advantages