Paddle Blade Mixers – Mixing an Environmentally Safe Solution for FCC Environment

  • FCC  Environment have installed two 7500 litre JR Boone Horizontal large scale paddle mixers in their Knostrop Treatment Plant in Leeds

FCC  Environment have installed two 7500 litre JR Boone Horizontal large scale paddle mixers in their Knostrop Treatment Plant in Leeds to treat and stabilise APCR waste from a network, of incinerators. Chosen for their robustness and reliability, the new mixers are now processing 25,000 tonnes per annum producing a stable material for safe landfill.

Air pollution controlled Residue is generated in the flue of large energy from waste processes such as FCC’s Eastcroft plant in Nottingham and is typically a powder mix of calcium hydroxide and sand. The powder is created when hydrated lime is introduced into the flue to remove atmospheric pollutants including heavy metals and hydrogen chloride. FCC Environment’s Knostrop plant takes in the resulting powder, using the JR Boone mixers to mix in acidified water and produce a ‘sludge’ that is safe for disposal to landfill.

High percentages of silica sand in the mix makes the process very abrasive, so the JR Boone mixers need to be very tough. The Paddle blade Mixers are fitted with wear-resistant mixer arms and blades, with the number of moving parts minimised. Two identical mixers are in place at Knostrop, between them processing around 20 tonnes per hour of waste material. The short length to diameter ratio of the mixers ensures that mixing is completed in the shortest time possible, while the ‘omega’ shape of the mixing vessel makes sure that all material in the mix is fully entrained by the blades, so every part of the powder is treated.

This project was first set out as long ago as 2010, and initial material trials were carried out in 2013, Ian Martin, FCC Environment’s  General  Manager at Knostrop stated: ‘Our customers’ incinerators are running constantly and we need to be able to process the waste on a continual basis. Any stoppages here run the risk of stopping the upstream process. He went on. “We identified the JR Boone mixers quite early on in the project and chose them because they are tried and tested and very robust. We worked with JR Boone on pilot plant, fine tuning motor sizes and looking at the way the equipment performed with different material densities.”

The Paddle Mixer is a very versatile machine also used as a processor-producing compounds with variable amounts of shear heat and under vacuum e.g. 100M HPBM for investment casting manufacturer Clan Ceramics  more information available on request). JR Boone also produce high shear Delta Blade mixers, low shear Helical Blade mixers and very low shear Rotary Drum Mixers for a wide variety of industrial applications. Mixers are available for test for each type of machine to demonstrate the clear  advantage in choosing Jr Boone mixers and blenders for your process.