Incinerator bottom ash (IBA) is made up of particles that do not fully combust in waste-to-energy facilities. IBA often contains precious and heavy metals, which can be recovered and recycled when processed properly. Few IBA treatments provide effective recovery of fine metals. As such, current recovery rates are suboptimal and inefficient. Sepro’s Fine Slag Treatment Plant (FSTP) offers a solution to this issue as it can effectively recover valuable fine metals.

What is an FSTP?

A Fine Slag Treatment Plant (FSTP) is Sepro’s proprietary system for wet processing of fine incinerator bottom ash. Wet treatment is far superior to a conventional “dry” processing of IBA because it is much more effective for recovering valuable metals.

The first step is to remove coarse material from the IBA using a jig or screen. The remaining particles, which are less than 2 or 4mm in size, are then sent to a magnetic separator. This easily removes the fine iron from valuable fine particles like gold and platinum. The iron concentrate can be used for particular smelting applications.

Now that the IBA has been sized and cleaned of magnetic particles, it can be processed by a series of gravity recovery technologies including a Sepro Slot Separator, a shaking table and a Falcon Concentrator. The shaking table exploits specific gravity differences to divide the non-ferrous metals into three fractions: heavies, middlings, and lights. The heavies fraction is made up of valuable non-ferrous particles and can be sold as a final product.. Middlings are sent back to the start of the circuit for reprocessing, and lights are sent to the Falcon Concentrator for recovery of the finest valuable particles.

The Falcon Concentrator is the key to recovering fine precious metals like gold and platinum. It uses powerful G-forces to concentrate valuable fine particles for effective metal recovery. The rejected particles are recirculated to the beginning of the FSTP. This recirculation improves the efficacy of the treatment plant.

What are the Benefits of an FSTP?

An FSTP uses multiple pieces of innovative equipment to increase the recovery rates of valuable metals. The plant has also made fine recovery of precious metals possible. Other benefits of Sepro’s FSTP are:

  • drastically reducing, if not eliminating, dust creation due to wet processing
  • eliminating the aging period required for dry IBA processing
  • easy integration into existing processes
  • cleaner final ash for safe use in construction materials
  • ability to be incorporated into existing IBA plants with no technical modifications
  • higher metal recovery rates thanks to better liberation
  • small environmental footprint

How To Get Started

If you’re looking to improve your metal recovery rates from your current incinerator bottom ash treatment plant, contact Sepro Urban Mining. Our Fine Slag Treatment Plant can be adapted to both wet and dry IBA treatments with no modifications. After a simple installation, you’ll start to reap the rewards of this proprietary system.