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Renewable Energy Research at DIMSET/SCL ( Savona Combustion Laboratory, University of Genoa) http://proxy. sv.inge.unige .it/SCL/.
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Renewable Energy Research at DIMSET/SCL (Savona Combustion Laboratory,University of Genoa)http://proxy.sv.inge.unige.it/SCL/
DIMSET/SCL is “Joint Laboratory” with Ansaldo Energiafor the joint development and testing of last generation, ultra-low emissions, gas-turbine burnersfor large-power combined plants (in the hundreds of Megawatt).As such, its researchers are directly responsiblefor the continuously increasing “fever” of our planet Earth.However, who is responsible of a sickness,has got a direct expertise about its causes,and, thus, is also a good candidatefor finding and pursuing its cure …..Do you agree?
Appropriate Technologies for Distributed Energy Generation in a Sustainable Development Scenario
Sustainable energies at DIMSET/SCL • The scientific/technological scenario at DIMSET/SCL is quite variegate, ranging from fossil fuel combustion to renewables. • However the mission is uniquely defined: to take advantage of the “fossil” expertise in order to pursue a progressively more sustainable perspective. • The corner-stones upon which the strategy is rooted are: • high-energy content, rapid-growth, wood-biomass agronomic cultivation • conversion of fossil-fueled burners to syngas- and bio-fueling • conversion from concentrated, electric generation to local poly-generation • natural-gas/biomass fueled combustors for Stirling-engines • wood-biomass combustion for boiler application • wood-biomass torrefaction and carbonisation technologies • wood-biomass/charcoal gasification technologies • co-combustion of pulverised coal and syngas from torrefied biomass
Sustainable Energy Development at DIMSET/SCL How to manage the issue of the Earth fever In the last 200 years, atmospheric concentration of CO2 has climbed from 270 ppmv to 383 ppmv. The trend is recently accelerating. On the land, the most efficient CO2 capturing mechanism is very easily traceable: it is located in the woods. The same mechanism features also a quite interesting by-product: atmospheric release of pure O2.
…first of all, an updating on Earth fever…. Intergovernmental Panel on Climate Change IPCC Fourth Assessment Report: “AR4” (December 2007) http://www.ipcc.ch/ (and, interestingly, the very recent establishment of the ACCC: “Abrupt Climate Change Commission”)
Sustainable Energy Development at DIMSET/SCL How to manage the issue of the Earth fever The strategy has got a name: “zero-emissions local power co-generation” The strategy is rooted upon the careful planning and the territorial “deployment” of modern agro-forest farms, pursuing agro-sylvicolture and “zero-net carbon release” energy production.
How to manage the issue of the Earth fever: some numbers (Europe) tons of Carbon stored in biomass per hectare of woods: 50 to 200 (tC/ha) yearly Carbon storage per hectare of woods: 0.80 to 3.5 (tC/y) C emissions per person-year: 1.5 to 6 (tC/person-year) C storage in woods / overall C emissions : 20% Bayern; 50% Sweden additional C storage in soil substrate: 4.5 to 11 (tons per hectare)
An Earth rescuing strategy, immediately deployable The C-mass capture numbers just seen can be dramatically improved by an immediately deployable technique. Namely: planting new trees, of “hardwood” type (rich in lignin content), characterised by rapid growth, organised in so-called “consociated woods”. Typical consociated trees: various types of Elm (Ulmus), Ash (Fraxinus), Wild Cherry (Prunus), Myrobalan (Prunus cerasifera), Mahaleb (Prunus mahaleb), etc. Suggestion: cut out old trees, shift to hardwood species, avoid species with low C-capture capability such as Red Spruce (Picea Excelsa)and similar species.
A Vision from DIMSET/SCL The above strategy is a well established operative know-how of a few forest-tree breeders in Italy, highly experienced in many successful trees-consociation plantations all over Italy. The consociated wood-trees, at harvesting, show an average wood-yield of about 140-200 metric tons/hectare/year, from 5 to 6 times more than the usual poplar, plane-tree or willow-tree cultivations. In addition, these latter would show heat values in the range of 2000- 2200 kCal/kg whilst the former’s heat values are in the range of 3000-3100 kCal/kg. Being the consociation self fertilizing, no watering nor soil enrichment is required.
Wood-Biomass Torrefaction at DIMSET/SCL Torrefaction is a feasible method for improving the properties of biomass as a fuel . It consists of a slow heating of biomass in an inert atmosphere to a maximum temperature of 300 °C. The treatment yields a solid uniform product with quite lower volume and moisture contents and sensibly higher heat values compared to those in the initial biomass. It is as a predictable, flexible fuel with optimum combustion and transport economies. Due to the low moisture content of torrefied wood, the transport cost is lower and the quality as a fuel is higher. It is easily packaged, standardised and transported, and thus constitutes an efficient fuel.
Wood-Biomass Torrefaction at DIMSET/SCL Torrefied biomass can be blended with coal and co-fired in a Pulverized Coal Boiler. The properties of torrefied biomass should lead to an improved operation in gasifiers for which the stability of the process is important. The homogeneity and the seasonal regularity of torrefied wood makes it an appropriate substitute for charcoal. While having the same utilisation as charcoal, torrefied wood offers more efficient utilisation of the wood and hence reduction in wood consumption. As a fuel it competes with the conventional sources of energy which often are imported.
Biomass Characterisation Laboratory - DIMSET/SCL(physical, analytical, thermo-chemical)
Wood Drier at DIMSET/SCL Temperature: up to 105 °C. Humidity: down to 9 %
Biomass Gasification at DIMSET/SCL Biomass gasification is basically a conversion of solid fuels (wood, wood-waste, agricultural residues, charcoal, etc.) into a combustible gas mixture normally called Producer Gas. The process is typically used for various biomass materials and it involves partial combustion of such biomass. Partial combustion process occurs when air supply (O2) is less than adequate for the combustion of biomass to be completed. In the following slides, the available technologies for low-power co-generation (up to 300 kWel and 500 kWth) are presented.
Biomass Gasification at DIMSET/SCL Downdraft gasifier: “Tar burning Char producing” Technology provider: ANKUR Ltd. located near the ancient “Sama Jakat Naka” Baroda-390008, Gujarat, India email: ascent@ankurscientific.com web: www.ankurscientific.com Electrical efficiency: 24% Investment costs: 2000 euro/kWel
Biomass Gasification at DIMSET/SCL To a Gas Engine Or Gas Turbine Conceptual Sequence of Processes from Biomass to End Products Product Gas Cleaning Equipment
Biomass Gasification at DIMSET/SCL • Fuel Parameters, Gasifier Performance, Product Gas, Slag, Emissions Monitoring • - Physico-chemical characterisation of fuel (woodchips and charcoal-woodchips mix) • - Air/Fuel Equivalence Ratio • - Inner temperature profile (overall gasifier) - Pressure drop (@ sand filter) • - Product gas temperature (@ gasifier outlet) - Water temperature (@ scrubbers) • - Product gas flow rate (@ gasifier outlet) - Water pressure (@ scrubbers) • - Inner gasifier pressure - Water flow rate (@ scrubbers) • - “Clean” product gas chemical composition - Condensate chemical composition • - Slag composition and mass flow rate - Condensate mass flow rate • - Exhaust gas composition and mass flow rate (@ gas engine outlet) • - Co-generation thermal power (@overall equipment and gas engine)
Temperature Distributions for Varying Fuel Typologies Biomass Gasification at DIMSET/SCL TC3 Wood@32% hu S-2 Wood@25% hu S-3 W@15% Coal TC2 S-4 TC1 W@30% Coal TC4 HEARTH LOAD OPTIMISED FOR MINIMUM TAR CONTENT 400 8001200 Biomass Gasification at DIMSET/SCL
Temperature Distributions for Varying Fuel Typologies Biomass Gasification at DIMSET/SCL S-1 TC3 TC3 Wood@32% hu S-2 Wood@25% hu S-2 S-1 Wood@25% hu Wood@32% hu S-3 S-3 W@15% Coal TC2 TC2 Wood@15% Coal S-4 TC1 TC1 W@30% Coal S-4 Wood@30% Coal TC4 TC4 HEARTH LOAD OPTIMISED FOR MAX GAS ENERGY 900 1800 Biomass Gasification at DIMSET/SCL
Product Gas Heat Values for Varying Fuel Typologies Biomass Gasification at DIMSET/SCL S-2 S-2 Wood@25% hu Wood@25% hu S-2 S-3 Wood@15% Coal Wood@15%Coal TC1 TC1 S-2 Wood@30% Coal S-4 Wood@30%Coal
Product Gas Flow Rate for Varying Fuel Typologies Biomass Gasification at DIMSET/SCL S-2 S-2 Wood@25% hu S-3 Wood@15% Coal TC1 TC1 S-4 Wood@30%Coal
Gas Thermal Power for Varying Fuel Typologies Biomass Gasification at DIMSET/SCL S-2 Wood@25% hu S-3 Wood@15% Coal TC1 TC1 S-4 Wood@30% Coal
Electric Power Generation for Varying Fuel Typologies Biomass Gasification at DIMSET/SCL S-2 Wood@25% hu S-3 Wood@15% Coal S-4 Wood@30% Coal
Tar and Particulate Levels for Varying Fuel Typologies Biomass Gasification at DIMSET/SCL S-2 Wood@25% hu S-3 Wood@15% Coal S-4 Wood@30% Coal