Current development and market needs for agrobiomass combustion in medium and large-scale. Jyväskylä Ari Kokko

Transcription

1 Current development and market needs for agrobiomass combustion in medium and large-scale Jyväskylä Ari Kokko

2 Agro biomass in fluidized bed boilers Content of the presentation Sources of biomass A method to reduce corrosion in BFB: CorroStop CFB design to manage challenging fuels Summary

3 Metso s products for agro biomass firing BioPower HYBEX CYMIC BioGrate or BFB Turn-key power plant Unit size 3-10 MW e BFB technology Hydro beam floor Unit size MW e CFB technology Water cooled cyclones Unit size MW e

4 Market need Market interest Low carbon fuel sources 0.01% Fuel Cl- content 0.05% 0.1% 1.0% Agro biomass Straw Sunflower hulls Corn Stover Miscanthus Recycled fuels Packaging waste Recycled wood Fast growing wood Willow Eucalyptus Fossil Hard coal Wood biomass Northern wood Pulp&Paper sludges Wood pellets Challenge 4

5 Metso HYBEX Testing agro and woody biomass co-firing 5

6 Metso HYBEX 20% grain residue with woody biomass Water soluble elements Acid soluble elements S Mg P Cl Ca Ca K K 6

7 Metso HYBEX CorroStop testing Elektrociepłownia Białystok S.A Białystok Poland Solid sulfur feeding 7

8 Metso HYBEX CorroStop long-term test UPM Caledonian paper mill Irvine, Ayrshire UK Steam Fuels 90 MWth 34 kg/s 90 bar 510 C Start-up 2009 Recycled wood, bark, sludge, saw dust, forest residue CorroStop system Feeding locations 14 nozzles at the level below the nose 4 nozzles at the sec. SH area 8

9 Metso HYBEX CorroStop long-term test CorroStop Liquid solutions Injection nozzles Sulfate in Sulfate water solution Sulfate tank Sulfate to levels Sulfate pump Dilution water Control of flow: Load, SO 2 and HCl before BHF & in the Stack 9

10 Chlorine content in the deposits (mol-%) Metso HYBEX CorroStop - results T FG ~720 C, T mat = 500 C Metso HYBEX - boiler CorroStop tests T FG ~680 C T mat = 400 C Fuel A: Bio 83% / RCF ~17% Fuel G: Bio > 90% / RCF < 10% T FG ~530 C T mat = 350 C CorroStop ON: Chlorine content in the deposits decreases below detection limit Dosing = 70 kg/h, corresponds increase of fuel S content w-% DS 2 0 CorroStop OFF: Chlorine in the deposits ~0,5-19 wt-% 10

11 Metso Corrored analyser Metso Corrored on-line analyser - Measurement location in upper furnace or at superheater region - On-line measurement of total Cl in flue gas (ppm 6% O 2 ) - Calculation to Cl in fuel (wt-%) Fuel quality control Metso on-line corrosion estimation (Index value) - Calculation algorithm based on measurements Index is developed based on empirical data from Metso boiler references and simulation tools Continuous measurement of corrosiveness enables corrosion control ON-LINE 11

12 How to minimize high temperature corrosion in CYMIC Co-firing sulfur containing fuel with biomass - higher sulfur content means that biomass alkalis are reacting with SO 2 forming alkalisulfates - Chlorine goes out as HCl OR Superheater having surface temperature >450 C is located in cyclone loop seal instead of 2 nd pass - Not in contact with flue gases - Surface is immersed in the circulating bed material 12

13 CYMIC demanding biomass reference: Porin Prosessivoima Porin Prosessivoima Pori Finland Steam Fuels 177 MWth 67 kg/s 84 bar 522 C Wood fuel, peat, recycled fuel, coal - Cl in mixture 0.1% Finishing superheater after h 13

14 Metso CYMIC design for SRF Water sootblowing Refractory covered furnace Replaceable superheaters Outside surface T ~ 700 C Inside T = C Flue gas cooling down < 620 C Final superheater in the loop seal bed 14

15 CYMIC SRF reference E.ON Norrköping E.ON Värme Sverige Norrköping Sweden Steam Fuels 75 MWth 27 kg/s 65 bar(g) 470 C Sorted MSW, industrial waste, sewage sludge, recycled wood - Cl content in fuel 1.0% Tube surface of replaced superheater after 3 years 15

16 Summary Agro biomass is very tempting choise to reduce CO 2 emission Lower quality fuels are less expensive, but they are also technically challenging Since 2000, Metso has sold almost 5 GW e of boiler capacity fuelled with renewables equivalent to 6 average nuclear reactors. CorroStop solution in BFB is a key to high temperature corrosion control with demanding biofuels Modern CFB boiler components enable higher fuel flexibility safely