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Company Information for Applied Silicate Technologies Limited
Company Statement
For many years, mining related industries (and more recently, those involved in biomass) have been troubled by the economics of how to turn particulate waste material into efficient, handleable and saleable end product.
When coal is mined, cleaned and transported, considerable quantities of fine coal (particles less than 5mm) are generated. This fine coal is often unsuitable for the end process and, even where the size is not a problem, retains large amounts of water (10%-30%) which can make it "sticky", difficult and inefficient to handle, transport and burn. A good example is the slurry ponds of waste coal dust which remain at mine sites after lump coal has been extracted and washed.
There are billions of tonnes of particulate waste around the world today, causing environmental problems and giving rise to significant ongoing costs to mining operators, product handlers and government agencies. Waste pile problems extend across many sectors of the natural resource industries with discarded heaps of various ore tailings spread across the world on many sites involved in the supply chain logistics.
The most widely used solution for utilising large fine waste volumes (which cannot meet primary characteristics for utilisation without processing) to date has been “briqueting” and “pelletising.” Typically, these projects face complex planning hurdles, display high capital costs, high manpower requirements and high ongoing energy input, in the form of heat and pressure, to turn fine particles into economically useful solids. The present high costs provide a severe economic barrier preventing extensive commercial processing of these waste streams.
The AST FuelForm® system, of which you are about to read, changes the economics of pelletising and briqueting fuels and biomass. The substantially lower overall costs of this unique system turns potential customers’ waste into high value raw materials and makes possible the commercial upgrading and blending of low rank, high moisture coals and biomass. The AST patented FuelForm® system marks a revolutionary rather than an evolutionary change for the industries concerned.
Coal and Fossil Fuels
Global Coal production in 2005 increased by over 9% compared to 2004, to over 5 billion tonnes/y and has increased over 65% over the last 25 years. With coal fines (upgrading waste) representing approximately 15% of these totals – or over 750 MT - and with over 2.5 billion tonnes of above ground proven reserves of fine particulate coal waste in the US alone; the size of this market, waiting processing, is very substantial.
High moisture levels in coal make transportation and combustion inefficient. Sub-bituminous coals, which comprise a large and valuable part of the world's coal reserves, contain "chemically attached" moisture within the coal structure (up to 20%-30% moisture). This "moisture" severely limits the use and value of sub-bituminous coals.
For every 3 truckloads of coal that is transported, one truckload of water must also be transported. During combustion this moisture also robs energy from the flame in order to turn to steam. Attempts to drive the moisture out by heating have proved unsuccessful because the coal falls apart as it dries and also becomes susceptible to spontaneous combustion. As a result, very little sub-bituminous coal is traded internationally.
The huge reduction in moisture content by using the AST FuelForm® system is a significant and substantial advantage, as it positively changes the combustion characteristics of any incorporated fuel by raising the useable heat value. Peat, lignite, low rank coals and washery tailings can become premium solid fuels with moisture content of 5% or less as opposed to smoky, low value second class substitutes, or, in some cases, discarded waste.
Company Diagram
The AST system
Operations and Technology
The AST patented FuelForm® system uses unique environmentally clean chemistry to produce weather resistant, hard-shelled, cold bonded spherical granular agglomerates (spheroid pellets) with a moisture content of less than 5%.
• The systematic processes require comparatively low capital investment and minimal energy (+/- 10kWhrs/tonne) input to produce these spheroid pellets, as opposed to standard briqueting and pelletising operations requiring up to +/- 250kWhrs/tonne.
• The FuelForm® system is significantly less complicated to implement and operate than comparative processes like traditional briqueting and pelletising plants, requiring significantly less labour and maintenance.
• The pellets are produced in a patented circuit by mixing coal fines or bio-wastes, or a combination of both with sulphur absorbents such as crushed limestone, in an agglomerator with a proprietary reagent mixture.
• The chemical reactions and physical processes in the agglomerator can be controlled during the pelletisation process to produce hard spheroid granular pellets from 10–100mm diameter, to customer specifications and requirements.
• The pellets then cure, utilising inherent chemical accelerated evaporation, requiring no added heat, pressure, or particular environmental conditions, for 7-14 days, at which point they can be easily transported as a bulk product.
• Pellet composition can be manipulated on a bespoke basis to reflect the curing environment or proposed use of the finished pellet.
• The agglomerator is highly mobile, and can easily be moved to the feed sources, rather than transporting the low value waste to a permanent fixed location.
• Coal, blended fuel and biomass spheroid pellets can be used directly or pulverised for use in power generation at major plants and display enhanced combustion characteristics due to very low moisture content and subsequent easier grindability.
• FuelForm® pellets can be used domestically in their spheroid form as easily flowing smokeless household fuel.
The AST FuelForm® system also allows for the easy combination of fine particulate feeds to produce composite fuel agglomerates. There is complete flexibility to allow “designer” or “made to order” fuels using both low and high calorific feed stocks for combustion in various types of existing boilers. This negates the need for specialist boiler design and installation for customers using FuelForm® pellets.
The system offers “industry changing” benefits for coal and biomass waste production companies, as it makes it commercially viable to carry out particle agglomeration on a much wider scale.
For users of the AST FuelForm® system, this means:-
• Producing more revenue from current operations and creating revenues from waste where there were associated costs before.
• Reducing environmentally damaging waste, demonstrating an environmentally positive opportunity for customer leverage.
• Utilising resources that presently are uneconomic to process.
• Improving product handling systems by improving material “flow” due to spheroid agglomerates rather than dust, slurry or angular lumps.
• Designing “new” product types, such as customised fuels.
• Improving productivity and greatly speeding up return on investment timescales.
As this system can be applied across many of the world’s major extractive and bulk processing industries, the benefits have the potential to be revolutionary.
Company AddressApplied Silicate Technologies Limited 8 Meadowbank Road Co. Antrim Northern Ireland
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