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CDS GROUP Incorporating R-O2 Bio Coal Technology Technology Presentation . Presentation Overview. Technology and Patents Plant Flow, Schemes and Processes BioCoal Characteristics BioCoal Plant – Photos of Build Co-Firing with BioCoal Plant Design and EPC. 52 International Patents.
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CDS GROUP Incorporating R-O2 Bio Coal Technology Technology Presentation
Presentation Overview • Technology and Patents • Plant Flow, Schemes and Processes • BioCoal Characteristics • BioCoal Plant – Photos of Build • Co-Firing with BioCoal • Plant Design and EPC
Unique Features • The R-O2 torrefaction technology is a patented method that uses dry SHS as the heating medium, to perform the drying and torrefaction processing • The dry SHS medium is uniquely created from the water fraction contained in the wet feedstock and is used at virtualatmospheric pressure • The R-O2 technology system operates on patented recirculation principles, and adopts proprietary thermal recuperative techniques, an off-gas processing system and a patented mano-metric density seal at the systems input and exit points
Technology Key Benefits • Faster initial drying times than conventional systems. • High drying / operating efficiencies. • Low supplementary energy input requirements. • Containment and use of exhaust emissions. • Low internal drying velocities to prevent ‘fly-away’ pick-up of light fractions product. • Low abrasion / friction to product. • Energy recovery options. • Sterile product and condensate from the process. • Inert atmosphere drying & processing conditions, eliminating potential of product combustion.
Independent Verification Independent Studies by the bodies listed below, have demonstrated that R-O2 Technology drying and processing technologies have demonstrated: • drying time reductions of up to 80%. CERAM Research
Best Practice Programme - Study Energy Efficiency Best Practice Programme (UK) Future Practice Final Report 58 by ETSU, Harwell, Didcot, OX11 0RA, acting on behalf of the DETR. Found: • R-O2 drying offers energy consumption savings over industry survey averages of between 60% and 85%.
BlockFlow Diagram Superheated steam at atmospheric pressure is created and re-circulated over an indirect heater and through the feedstock, to dry and torrefy the material
Torrefaction Process Purified Flue Gases / Recoverable energy source Thermal Oxidizer Vapor (+odour) Energy (pyrolysis gas) Energy (heat) Shredding Drying BioCO2al Plant Cooling BioCO2al Energy (heat) Energy (heat) Fines Solid Fuel Furnace
The patented drying technology operates by creating super heat steam (SHS) for its drying medium. This SHS is generated solely from the evaporating moisture contained within the biomass feedstock as it is dried The creation of SHS displaces air/oxygen from the process and creates the inert “low level oxygen” atmosphere for high temperature drying 150ºC Drying Phase
Directly from the drying process,the woodchip is transferred into a continuous rotary torrefaction processor via airtight sealed conveyors A mild thermal pyrolysis in a SHS atmosphere (240 - 280°C) converts the wood chip/biomass into biocoal The biocoal is then “cooled” to below 130°C before discharge to atmosphere Biocoal is ready for grinding, pulverising or densification Torrefaction Phase
Thermal Recuperation and Off-gas • The off-gas from the torrefaction process is sent to a thermal oxidisation system for destruction and cleaning before being exhausted to atmosphere free from VOCs • The oxidiser operates at around 750 – 800°C and the torrefaction gases are exposed to this heat source for a minimum of two seconds to effect complete destruction of the VOC’s and other organic chemicals[12] • The energy recovered from the thermal oxidation of VOC’s should be used as an additional thermal source in both drying and torrefaction processes, thus reducing fuel (natural gas/oil) required to indirectly heat the re-circulating drying and torrefaction gases.
Key Criteria Capital costless importantthan Operational cost Safety Efficiency Up-time Speed of repair/replacement Scaleable and modular
R-O2 Design Advantages Energy optimization important (cost) Equipment selection Efficient - Safe (explosion hazard) - Scalable Robust - Reliable - Modular Bankable - Up time is high - Guarantees Low energy requirement in combination withenergyrecovery potential High thermal processefficiency Using super heat steam, a big advantage Louvre drum design is an ideal optionfor fast, consistent, efficient, safe drying & thermal processing Able to process largerparticle sizes
AirlessTM Louvre Drum Different size options Same equipment type useable for all processing steps Experience with different drum design technologies Adaptation for specific conditions/requirements possible
Thermal Oxidisation Post torrefaction VOC‘s gas thermal treatment technology Proprietary equipment design Energy Recovery using air,water, thermal fluid etc Energy re-use in drying and thermal processing Bag house for elimination of particulate emission Maximum energy recovery/re-use
Biomass Boiler Heat recovery using thermal fluid Fuelled primarily by Biomass fines Bag house filter Classical grate stove
Emissions Management Emissions Odour, wood gases, acids, dust emissions (ash, soot) No contaminated water Measures taken All off gases, combustible gases and vapours from drying and torrefaction are sent to Thermal Oxidiser for complete destruction/clean-up Bag houses in the effluents from Thermal Oxidiser and from boiler Emissions will observe Local Standards
Wood Reaction Characteristics Torrefaction of wood in an inert atmosphere: • Up to 160°C wood mainly loses its water • Between 180 and 270°C wood gives off additional moisture and begins to darken and brown, giving off cellulose, carbon dioxide and wood acids. Wood at this stage loses its hygroscopic properties and becomes more friable than untreated wood but less friable than charcoal • Torrefaction occurs between 240 and 280°C and wood at this stage in the process acquires the properties that are specific to BioCoal
BioCoal Characteristics • Has heating value close to steam coal with LHV of 20 to 22 MJ/kg • Is CARBON NEUTRAL as it has no net release of CO2 • Is consistent and homogenous. Different types of feedstocks have similar physical and chemical properties after torrefaction, which is important for process optimization and control • Can be pelletised / densified at costs much lower than even saw-dust for distant shipments • Is densifiable to sub-bituminous coal level (16-17 GJ/m3) - higher than bio-pellets (~10 GJ/m3) • Is friable and has greatly improved grinding properties, when compared to raw biomass or wood pellets • Becomes hyrdophobic to atmosphere moisture re-absorbtion (ideal for external stock piling)
BioCoal Pellets • address the drawbacks encountered with the durability and biological degradation of biopellets (storage of biocoal pellets is therefore simplified) • can be applied to wide variety of biomass (sawdust, willow, larch, verge grass, wood, energy crops, straw etc) yielding similar qualities, thus increasing the feedstock range for pellet production • offer a solution to low volumetric energydensity of torrefied biomass[2]
BioCoal Pellets Production Operational Benefits: • the energy consumption of the biocoal pelleting process is lower than the conventional pelletisation, due to lower energy consumption used for material sizing and pelletisation (despite increased energy consumption used for torrefaction) • the desired plant production capacity can be established with much smaller equipment [3] • The torrefaction gases can be recovered and used for drying, instead of using fossil fuel as utility fuel
Co-Firing at Essent • 30 tonnes of torrefied BioCoal was manufactured using the R-O2 technology and was test co-fired with coal at EPZ's 400 MWe PC-plant unit BS12, located at Borssele, The Netherlands, operated by Essent Energie (for co-pulverization and co-firing testing) • At the plant, BioCoal was fed into a single coal pulverizer, a CE model with conical rollers and rotating classifier, with 100 MWe capacity • Biocoal was mixed with coal up to 9% (energy basis) and injected to the boilers
There is a capacity for increasing the co-firing ratio, as the pulverizer’s limits were not reached[7] • That ‘the significance of torrefied biofuels is that it will allow a much wider slate of biomasses (both woody and otherwise) to be conditioned for direct co-pulverizing and co-firing’ [7] Essent Energie, Borssele, The Netherlands
Institute for Energy findings • By far the most economical option for co-firing of coal and biomass is to co-mix the fuel stocks prior to grinding and injection into the fuel combustors at maximum ratios • This avoids the need to retro-fit dedicated biomass injectors to the plant • By contrast, the tough, fibrous nature and higher MC of raw biomass means that the biomass proportion is limited, typically to <7% by weight Institute for Energy, Petten (the Netherlands)
Institute for Energy findings continued • Attempts to increase the BioMass proportion beyond this limit typically lead to problems: • insufficient throughput • overheating and failure of the grinding mills • clogging of pneumatic fuel transfer systems • an unacceptable proportion of over-size particles reaching the injectors, and • unpredictable thermal transients in the combustion chamber [1] Institute for Energy, Petten (the Netherlands)
Institute for Energy findings continued • Torreffied Biocoal however: • destroys the fibrous structure of the raw biomass • reduces the MC and • provides a narrow range of calorific content thereby allowing a much greater biomass proportion to be combusted in existing installations [1] Institute for Energy, Petten (the Netherlands)
Torrefaction and Grindability • ‘…it is concluded that the grindability of raw biomass can be improved [using torrefaction] to the level of coal using the temperature range of 260 – 2800C…’ Ref: Torrefaction for biomass co-firing in existing coal fired power stations ‘P.C.A. Bergman, et el July 2005
