CORDIS - EU research results

Efficient Aluminium Salt cake Recycling Technology

Periodic Reporting for period 2 - AluSalt (Efficient Aluminium Salt cake Recycling Technology)

Reporting period: 2016-09-01 to 2017-10-31

ALUSALT™ is an economically viable way of recovering and recycling materials to increase furnace efficiency, reduce transport and third party processing costs and reduce landfilling (especially regarding hazardous materials). End users will increase capacity without more furnaces and gain lower energy usage per tonne of aluminium produced. Reprocessing salt slag in house, extracting further aluminium for re-cycling, re-using the salt that is used in the rotary furnaces to maximise aluminium recovery from scraps and drosses, and selling inert Non Metallic Products (NMP) extracted from salt slag to maximise the value of salt slag allowing smaller companies to be competitively priced.

All of this leads to a technology that allows full use of all by products from the aluminium recycling process, and supports the global drive to a circular economy.

The approach gives far greater flexibility and economic viability to Al recycling plants, enabling them to meet increasingly stringent Global legislation, improve financial performance and reduce their environmental impact. We also believe it will encourage many other smaller operations who have struggled with the management and disposal of the salt slags when using a Rotary Salt Furnace, to invest in this type of technology and enter the market in recycling (possibly at local levels, leading to further reductions in transportation and CO2 emissions and better localized aluminium scrap sorting and collection.

The project objectives are to develop the work completed in FP7 (pilot lab scale) and upscale the concept to a fully functioning demonstration plant. This will then operate within the confines of the project to provide detailed data for the marketing and dissemination of the plant design. It will allow potential interested parties to visit the plant and verify the economic data and ROI models for their operations, before making the investment decision.
The upscale design and development has been completed with significant trial work being completed within the Pilot plant to provide data which has assisted the design and development of the full sized demonstration plant. Significant purchase activity has been conducted to provide key equipment for the building of the upscale plant. Detailed layouts have been agreed with the End user partner ( detailed pictures are shown)

Detailed chemical analysis of the process has been developed within Altek utilising various methods to clearly identify the phases of reaction throughout the process.

Detailed Gas analysis has been conducted during the processing of the Aluminium Salt Cake within the pilot plant which has clearly defined the on-going development of the upscale project and given significant data to drive a industrialised design.

The generation of the dangerous off gasses had been a major concern at the commencement of the project, however after careful design and detailed laboratory testing these gases can be kept to a minimum of generation through control in the process parameters.

This work has enable the upscale design to be adopted to the foundry environment where it will be operated. Previously it needed a large scale chemical process plant methodology.

The design of the plant is very modular allowing for an easier commercialization of the technology to the market, with lower and more manageable CAPEX and OPEX compared to the traditional large scale centralised processing facilities.

The plant as built has been operating with a wide variety of salt slags to prove its flexibility and performance.
ALUSALT is the first aluminium salt cake processing plant of its kind to offer economic, efficient recycling of small to medium volumes at source.

ALUSALT Processing solution incorporates Crushing and separation of AL for reuse and then leaching and filtration for separation of soluble/insoluble components including Al2O3 and other non-metallic products. Running small to medium batches via multiple filtration stages, it is capable of full process control irrespective of salt slag composition. The ALUSALT intelligent control system achieves this via statistical process control to manage operating cycles, key for controlling reactivity in the residual NMP, and soluble quantities in the resulting filter cake. ALUSALT process is strictly controlled enabling the limiting of emissions to a trace amount. The Process system is engineered to meet ATEX requirements.

The resulting brine liquor is fed through a dedicated Patented recrystallization system.
NMP and aluminium oxides are extracted via filtering post leaching made safe for sale as by products providing a further source of revenue for clients and eliminate landfill.

The H2020 ALUSALT full scale demonstration project has been a great success.

While the work will continue to further optimise the plant and the operation, we have fundamentally proved that the system developed from a small lab/pilot scale project under the FP7 programme in 2011-2014, has been possible to scale up to a full size, capable of meeting the requirements of normal production scenarios in the target market for exploitation, and meet the requirements of the European (and global) aluminium recyclers that require to locally and economically recycle their salt slag.

The initial commissioning and ramp up results we have obtained from the demonstration plant, have given full confidence that the equipment is scalable and all main process considerations are proven, allowing full commercialisation to start of the technology.
In summary we have proven that the three outputs of salt slag that is generated at the aluminium recycler; Aluminium, Salt and the remaining NMP (oxides) are fully re-useable at the recycling facility (aluminium recycled to produce new re-cycled aluminium, the salt re-used in the recycling facility, and the oxides (NMP) suitable as feed material to other external industrial processes (in this case steel and cement). Further work will be undertaken to further develop this aspect to widen the potential end use markets and value potential.

Due to the multiple client visits to investigate and verify the technology, who ultimately have been interested in purchasing the ALUSALT technology, and having now received our first commercial order for a mid-size (Model 3) system, and several Letters of Intent under discussion, ALTEK are very confident of their predictions for the commercialisation of this technology into the market.

Our ongoing commitment, at ALTEK’s own cost, to continue to further optimise and develop the demonstration plant, and the several recent articles in leading aluminium journals, press releases and invited conference presentations by leading aluminium conference organisers only further supports this situation.

To further support his position, ALTEK have now established a dedicated ALUSALT team, thoroughly re-affirms ALTEK’s commitment to fully exploiting this technology into the European and International aluminium industry.

The economic benefits through increased employment (both ALTEK and ALUSALT supply chains), massive potential reductions in CO2, reduced environmental impact, cost savings and competitive advantage for European aluminium operations, allowing for improved investment opportunities and growth/security of their operations are very significant.
Plant Layout
Plant Model
Plant Model 2