Philosophy – Paradigm Shift of the Aluminium Industry
Bauxite Residue from the Bayer-process is neutralized/ detoxified /chemically modified and subsequently dried to obtain a novel mass raw material that is produced without creating any waste (cradle-to-cradle concept). This new material is named ALFERROCK and put to industrial use in a multitude of mass applications. Three major applications are in flame retardancy for housing/construction materials, water- and air-purification and sensitive high-temperature energy storage. During conversion of both hazardous and toxic Bauxite Residue into ALFERROCK no waste is produced thus creating a paradigm shift within the alumina industry. The chemically neutral product resulting consists solely of inorganic compounds of the elements iron, aluminium, titanium, silicon, sodium, potassium, calcium, magnesium and trace elements.
Most importantly, the potential availability of ALFERROCK is enormous. Annually and globally 150- to 200 million tons of bauxite residue are produced and there are billions of tons available in the multiple deposit sites from the past. The industrial applications mentioned in the beginning comprise the technical and economical solutions for the both ardent and globally challenging problems. ALFERROCK-raw material being available globally, these problems can be addressed around the world immediately.
ALFERROCK characteristics are:
- Neutral – longevity guaranteed
- Chemically inert – totally recyclable
- Non-dangerous – highly economical
- Fine grained powder – highly ecological
- Free flowing powder – highly efficient
Properties of ALFERROCK
Within ALFERROCK aluminium is contained in the form of Gibbsite (Al(OH)3) or Boehmite (AlOOH), iron in the form of Goethite (FeOOH) or Siderite (FeCO3).
When ALFERROCK is calcined up to 1000°C these hydroxides, oxyhydrates and carbonates are decomposing endothermally into the respective oxides plus water and carbon dioxide.
ALFERROCK shows a very fine particle size distribution, has a high specific inner surface area and exhibits a high pore volume together with the ideal pore size.
ALFERROCKs chemical composition leads to important precipitation- and Redox-reactions respectively.
Annealing ALFERROCK to temperatures above 1000°C and more all the hydroxides, oxy-hydrates and carbonates within are transformed into the respective, permanently stable oxides and other thermally stable moieties. The resulting ceramic material shows excellent thermophysical properties (density, specific heat capacity and else).
Taken all this into consideration ALFERROCK is ideally suited to
- Inorganic flame retardancy.
- Removal of hazardous substances from aqueous, gaseous and solid systems including permanent immobilization of these substances.
- Applications in the areas of “Heat/ energy storage, heat / energy exchange and heat /energy recovery /recycling.
Inorganic halogen free flame retardancy plastics as compound or in foams including thermal insulation
In this application, ALFERROCK is used in the non-annealed /tempered form. This translates into aluminum being present as hydroxide or oxy-hydrate and iron being either present as hydroxide or as carbonate.
ALFERROCK halogen free flame-retardancy is procured by the release and evaporation of first water from the hydroxides and oxyhydrates and secondly of carbon dioxide from the carbonate with in both cases oxides staying behind as heat insulators. Both release processes being endothermal is contributing to the fire suppressing properties of the ALFERROCK “zero-halogen flame retardants (OHFR)”-system.
Removal of hazardous substances from aqueous, gaseous and solid systems including the permanently immobilization of these hazardous substances
In the removal of hazardous substances, ALFERROCK performs both adsorption and chemical reactions. Here ALFERROCK is utilized in the form of granules.
ALFERROCK is a universal water-purifying agent for:
- Trace-/ metabolite- substances like – Diclofenac and Metoprolol.
- Cationic hazardous substances, e.g. heavy metals like Pb, Cd, Zn, Ni, Cu, As, Cr and else.
- Anionic hazardous substances like phosphate, nitrate, arsenate, bromate and manganate; phosphate can be precipitated and thus recycled.
ALFERROCK with adsorbed hazardous substances in it is irreversibly built into GEOPOLYMER and finally and permanently deposited under-ground (e.g. old mines).
Heat storage, heat exchange and heat recovery /recycling
In the area of energy applications ALFERROCK is used solely in the form of ceramic material after heating in a special regime to more than 1000°C. All chemicals contained within ALFERROCK are now present in thermostable forms only, like oxides, titanates, silicates. These substances are completely inert against multiple cycles of temperature changes during the application.
This substance presents extraordinary thermophysical properties. The specific heat capacity is .791 kJ/kg * K @ 30°C, increasing to 1.037 kJ/kg* K @ 584°C and is rising to about 1.14 to 1.18 kJ/kg*K @ 1000°C (extrapolated). The specific density is 3.63 g/cm3 @100°C, raising to 3.93 g/cm3 @ 1000°C respectively.
Heat transmission capability depending upon different parameters can be controlled accordingly. As an example 1 m3 ALFERROCK is capable of storing 4.1 *106 kJ/m3 or 1.14 MWh of energy @ 1000°C.
The storage of (e.g. electrical) energy into ALFERROCK is performed by means of electrical heating cartridges (resistance wiring heating) directly inserted, which show an efficacy level of 95 to 100%. The retrieval of the stored energy is achieved by conventional heat exchange / turbine /generator technology well known and state-of-the-art in power plants of all sizes. The outstanding and at the same time the most important fact is, that the ALFERROCK energy storage system can be loaded and unloaded in parallel, which is up to now impossible with all other known storage concepts. The application of the ALFERROCK technology automatically will lead to a both smart and decentralized power supply making high-voltage power line highway construction so controversially discussed and disdained at the time being completely superfluous:
Moreover, by coupling several ALFERROCK Energy Storage Modules either very small or very big amounts of energy are storable and procurable.
- The overall efficiency of already existing wind energy parks is massively increased when ALFERROCK technology is applied. Upon its realization all kinds of emergency-power installations as well as pumped energy storage are rendered obsolete.
- The demand for conventional power plants running on idle to jump in, when the renewable energy supply is running low, is obliterated, together with the high cost resulting from this stop-gap measure.
In general, the energy supply business will have to be re-invented undergoing a drastic paradigm shift for good.
Fundamental progress of the aluminium industry in both economics as well as ecological aspects
In the alumina refinery industry about half of the raw materials employed has to be deposited at the end of the process with high costs creating deposit sites that will need continuous monitoring forever. The resulting materials, aluminum hydroxide, smelter grade alumina and finally aluminum metal are subject to the pricing regime of the London Metal Exchange (LME) in London, UK. This way, the pricing is absolutely dependent upon the LME that rules the industry. By marketing (processed) bauxite residue as ALFERROCK in e.g. the chemical industry, the water purification industry or the energy industry the dependency upon LME price finding is gone forever. The new price-finding process opens new horizons and the aluminum metal industry can outreach to new fields of applications, because the aluminum metal price will be much more affordable in applications where material cost is the most important point. In the last stage, all existing deposit sites of bauxite residue will be re-opened for the raw material stored: waste will become valuable industry raw material for usage in the most urgently pressing problem sectors in the world.
All the problem fields mentioned are existing worldwide. Bauxite residue is available worldwide in enormous amounts waiting for use as ALFERROCK. This availability is the major key to tackle the problems described in real-time / simultaneously.
This way the international activities like climate change control, renewable energy regime and all the other activities can be put on the fast lane by employing ALFERROCK technology and be successfully employed on the long run. Technological solutions being present politics can act immediately.
ALFERROCK technology has been fostered and nurtured over many years in the laboratories of Fluorchemie Group together with institutions like Fraunhofer ICT / Pfinztal, many institutes of the TU Bergakademie Freiberg /Saxony, University of Bayreuth, and RWTH-Aachen- ISA Institute, beside other institutions. The ALFERROCK know-how led to patents registered as well as pending worldwide.
The trade name “ALFERROCK” has been registered worldwide accordingly.