PROJECT AWIRS 4 WOOD PELLETS

Transcription

1 PROJECT AWIRS 4 WOOD PELLETS Liège 1 NEW WAY : IMPORT OF (WOOD) PELLETS Wood «pellets» Already tested Peanuts husk Sunflower Later on other «pellets» cereals coffee husk great excess of wood residues in the world = large potential on the long run controlled sustainability ( «FSC» certification of woods) controlled energy balance (energy consumption for production and transportation) 2 1

2 Wood pellets production Grinding Produced in pellet mills dry up to moisture content < 17% grind with hammer mills compress up from 200 kg/m 3 up to 650 kg/m 3 3 Test performed by Electrabel Swedish norm ASAE (Dec96) or European TC-335 DURABILITY Already test other possibilities Expansion under water (CRAGx, Gembloux) EXPANSION Density BULK = 650 kg/m 3, INTRINSIC = 1280 kg/m

3 Wood pellets spec s 4 10 mm mm Quality norms pellets sept-04 Parameters Units Electrabel Diameter mm 4-10 Length mm Volatile matter Water content % DM < 10 % Bulk (apparent) density kg/m3 > 600 Low heating value GJ/ton ar > 17 Ash content % DM < 1% Bark content < 5% Initial melting temperature (red cond) C > 1200 C Cl % DM < 0,03 % S % DM < 0,2% F ppm < 30 Additives (past, vegetal oil) % FORBIDDEN Waste wood Qualitative FORBIDDEN Heavy metals As mg/kg DM < 2 Cd mg/kg DM < 1 Cr mg/kg DM < 15 Cu mg/kg DM < 20 Hg mg/kg DM < 1 Pb mg/kg DM < 20 Zn mg/kg DM Benzo-a-pyrene mg/kg DM < 0,5 Pentachlorphenol mg/kg DM < 3 Particle size distribution minimum % < 3.0 mm (Durability) 100,0% % < 2.0 mm 95,0% % < 1.5 mm 75,0% % < 1.0 mm 50,0% 5 Awirs Unit 4 power plant Boiler manufactured by Cockerill Metallurgical Industries : - natural circulation - license Combustion Engineering Oil gas unit commissioned in 1967 Converted in 1982 to coal gas Power level :125 MW Steam : 390 ton/h, 145 bar, 545 C 6 3

4 Project diagram wood pellets hammer mills boiler electricity network unloading flue gas pellet silo s steam wood dust silo natural gas fan boiler electricity generator 7 Facts and figures plant 34% efficiency 80,3 MWe wood pellets 17 GJ/ton 4,7 MWhp/ton 1,6 MWhe/ton tons/year 50 tons/h generation 7000 hours MWh green certificates 0,70 tau(co2) min certificates/y 8 4

5 Major Project Constraints Existing old power plant Short delay : 7 months for realisation Commissioning : August 2005 Full substitution of coal : «World Premiere» Must be fully reversible to coal in 3 weeks time Safety issue: fire and explosion with wood dust Delivery wood pellet : just-in-time 1200 tons/day Steam : 510 C instead of 545 C Power level : 80 MW instead of 120 MW with coal 9 Unloading flatboat ton unloading with mobile crane Just-in-time delivery With unloading 200 t/h screening, filtering

6 Conveying belts FILTER 2 FILTER 3 HOPPER TR5 TDB3 old coal conveyor (350 m) TDB2 new TDB1 new FILTER 1 TDB0 CENTREX 2 CENTREX 1 all conveyors fully covered 11 Handling hopper, sieve 5 cm and filter weight balance metal detector Over band

7 Hammer mills two mills supplier : Brabant van Opstal capacity each : 25 ton/h silo s of 20 m 3 per mill (density of wood dust about 0,4) safety: - sparkling detection - water µ-pulverisation - water deluge - Fike explosion extinguish devise 13 2 BVO hammer mills outlet coal hopper inlet mill hammers 25 ton/h Mill selection criteria Electricity consumption Required particle size distribution : 90% < 1 mm, 100% < 1,5mm Cost : investment + maintenance sieve grid 2,5mm selector at inlet stones sieve and magnetic metal separator

8 2 BVO hammer mills 25 ton/h sieve grid 2,5mm Mill sieve grid Opening holes Required particle size distribution : 90% < 1 mm, 100% < 1,5mm permeability : 30 to 50% Mill powder level indicator Ultrasonic LT Capacitive LT Capacitive LT with 2 of 3 function Cleaning system Mill hammers Number of hammers Size and length of the hammers Material to withstand wearing (Crosabro, Nihard) Cost : unavaibility+ maintenance hammers stones sieve and magnetic metal separator 15 Burners Turbulence devise Pre mixing room Primary air wood

9 Safety measures Fire & explosion (Atex 137) Inside the bins : explosive mixtures Training of personnel about dust explosion safety, Prevention equipments Electrical installation (zone 20) static electricity links Spark detection Water µ-pulverisation Water deluge metal detection CO detection in the building Special safety design of fuel bins 17 Overview safety systems sprinkler system Water deluge infra-red spark detector FIKE bottle

10 Fire explosion suppression system Active system Explosion detection via pressure sensors Injection of extinction agent (sodium bicarbonate) N 2 is propulsion agent Container of explosion Control panel pressure (bar) extinction bottle explosion sensors Explosion Detector resistance limit Operation of the explosion insulation time (msec) 19 Two existing coal bins Volume of 600 m3 Fuel bins Limited residence time : 10 hours Re-used avoid 6 months delay for permitting Temperature detection and water deluge system Fike bumb R2 Extractor TR5 Arrival of the TDB3 CENTREX 2 CENTREX

11 Gaseous emissions Awirs4 Dust SOx NOx mg/nm 2 results limits before 1/1/2008 limits after 1/1/ Growth of pellet market in the EU Growth of pellet market in the EU Source Peter W. Heller 09/04, PerEnergy gmbh

12 Wood pellets Electrabel in 2006 Requirements : (Awirs4) Pellets Feedstock Electrabel British Columbia Main supplier Germany Russia Lethonie Finland Sweden 23 ELECTRABEL BELUX Awirs 4 Wood Pellets

13 Questions?