Gravity thickener HR

for wastewater treatment plants

Overview
Thickeners are industrial equipment used for liquid-solid separation and dewatering across multiple industries and applications, including densifying product for efficient processing, countercurrent decantation (CCD) washing, clarifying wastewater streams, and tailings management in mining and aggregate processing applications. Depending on the application, the valuable product can be the clarified liquid (overflow) or the thickened solids (underflow).

How Diefenbach Thickeners Work
Diefenbach thickeners comprise a tank, feed pipe and feedwell, rotating rake (with pickets depending on style), a bridge containing the rake drive mechanism, and a chemical dosing system. The slurry feed enters via a de-aeration tank into the feedwell. Chemicals (flocculants or coagulants) are added to promote rapid settling by forming larger, heavier particles. The rotating rake moves settled solids toward the central discharge cone for underflow removal. The clarified liquid overflows the top weir and is routed for further processing or reuse as process water.

Key components

• Tank (fabricated; larger tanks may have sag steel floors)
• Feed pipe and advanced feedwell (for optimum floc distribution)
• Rake mechanism and pickets (style-dependent)
• Bridge with rake drive
• Chemical dosing system (for flocculants/coagulants)

Features & Benefits

• Modern feedwell designs enabling maximum underflow density with reduced polymer consumption
• Auto-dilution options to increase settling rate, reduce equipment size and maximize clarity and underflow density
• Advanced automation and remote monitoring/assistance packages available
• Density monitoring systems and automated rake lifts for optimized control of bed level, underflow density and automation of underflow pumping and rake lift settings
• Liquid recovery rates of 85% or greater, producing a virtually solids-free overflow for reuse or further processing
• Reduced volume of waste material by generating a denser solids underflow, lowering storage requirements and downstream load on equipment such as filter presses

Types / Product family

• Elevated High-Rate Thickeners — HR Series: fabricated sag steel floors on larger diameter tanks; open access under tank for efficient underflow pumping; suitable for recovering reusable process water or separating solids from leach liquor
• Paste Thickeners — P Series: designed to achieve the highest solids concentration and maximum recovery of process water or leach liquor

Why Diefenbach
Diefenbach thickeners are designed using decades of liquid-solid separation experience, computational fluid dynamics (CFD) modeling and material testing in their in-house lab. Innovative feedwell designs and engineering best practices are used to achieve ideal liquid-solid separation for a wide range of applications, including CCD washing and tailings management.

Applications

• Mining & mineral processing (tailings management, clarification, CCD washing)
• Aggregates
• Battery recycling and PET recycling processes
• Chemicals and food & beverage (clarifying streams and recovering process water)

Technical characteristics / specifications

• Typical components: tank, feedwell, rake & pickets, bridge & drive, chemical dosing system
• Chemical treatment: flocculants or coagulants added at feed to promote settling
• Underflow handling: rotating rake moves solids to central discharge cone for underflow removal
• Overflow: clarified liquid overflows weir; near-solids-free overflow intended for reuse or further processing
• Automation: optional advanced automation, remote monitoring, density monitoring and automated rake lifts
• Performance: liquid recovery rates of 85% or greater reported
• Product family: HR Series (Elevated High-Rate) and P Series (Paste Thickeners)