1 / 24

Energetic aspects of urban waste treatments Claire Lecointe, Charlotte Barbut

Energetic aspects of urban waste treatments Claire Lecointe, Charlotte Barbut. 2 nd AWAST Workshop November 28-30 th , 2001, Rennes. SUMMARY. Introduction Thermal treatments Incineration Thermolysis Biological treatments Methanisation Landfill Composting Exergy Conclusion.

dore
Download Presentation

Energetic aspects of urban waste treatments Claire Lecointe, Charlotte Barbut

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Energetic aspectsof urban waste treatmentsClaire Lecointe, Charlotte Barbut 2nd AWAST Workshop November 28-30th, 2001, Rennes

  2. SUMMARY Introduction • Thermal treatments • Incineration • Thermolysis • Biological treatments • Methanisation • Landfill • Composting • Exergy Conclusion

  3. Introduction • waste treatments => energy production (steam or gas) • steam or gas => electricity or heat • gas => fuel for buses or injection in natural gas networks • but different outputs • and how to compare ?

  4. Thermal treatments

  5. Smokes treatment Dust removal Smokes cleaning Ventilator Heat recovery (boiler) hs+ he = hcg Steam Combustion C (T’ ; P1) alternator hc turbine Waste delivery Electricity W LHV Slags treatment Steam Q (T ; P2) Selfconsumption Selfconsumption Electricity sold Steam sold Incineration thermal treatment with oxygen (even air excess) ; 900 to 1000°C

  6. Outputs Rough estimates • combustion output : hc = C / LHVwaste • electric output : he = W / LHVwaste • heat output : hs = Q / LHVwaste • co-generation output : hcg = he + hs => 75 to 90% => 4 to 10% with counter-pressure => 60 to 70%

  7. Results for 5 french installations

  8. Smokes treatment 90 MJe/t Heat recovery Dust removal Smokes cleaning Ventilator 4 MJe/t 50 MJe/t 36 MJe/t Steam/electricity conversion 80% consumption Steam Combustion 78 MJe/t Waste delivery 5 MJe/t Electricity Steam 191 MJe/t Slags treatment 2,7 MJe/t Selfconsumption Selfconsumption Electricity sold Steam sold Electricity consumption : Strasbourg 2MWe 211 MJe/t

  9. Pyrolysis gas (H2, CO2, CO, CH4…) Waste Drying Heating Pyrolysis Ash cooling Residues (liquid, solid) Thermolysis thermal treatment without oxygen ; 400 to 600°C or 600 to 1000°C

  10. Development stage No industrial installation in France => no data => Do we keep this process in the project ?

  11. Biological treatments

  12. heating biogas CH4, CO2 electricity Energy recovery fuel injection in natural gas network CO2, H2O solid residues compost Maturation Waste delivery Reactor Press heating solid residues pressing juice sludge water excess Centrifugation Methanisation biological treatment without oxygen ; 35°C or 55°C

  13. heating biogas electricity Energy recovery fuel Deposing and compaction Waste delivery injection in natural gas network leachate Landfill natural biological decomposition

  14. Biogaz composition

  15. Biogas : energy recovery

  16. Results for methanisation

  17. Methanisation : biogas 1663 to 2862 MJLHV/t methanised waste Results for landfill

  18. Farm building : 0,54 MJe Heating : 0,045 L fuel heating Biogas extraction : 4,9 MJe Energy recovery electricity fuel Deposing and compaction Transport Waste delivery injection in natural gas network 1,3 L fuel leachate Landfill : energy consumptionfor 1t waste

  19. landfill emissions intensity leachate biogas landfill acceptable concentrations methane stage year 10 100 1000 controlling stage Landfill : problem of time limits

  20. Composting biological treatment with oxygen • This process doesn’t product any energy but uses it. • It allows material recovery by transforming organic waste in compost which can be used in farming. • Not yet studied because of lack of data.

  21. Exergy

  22. Wt heat machine S (T) Wg = -Ex Q (by agreement) Carnot engine Wc Qa = Q * Ta / T Ambient environment (Ta) Definition Exergy is the maximum part of energy in a system which can be changed in mecanic energy. mecanic and electric energy = pure exergy heat energy = exergy + loss

  23. Exergetic assessment Rough estimates • Carnot factor : qc = 1 - Ta / T • exergetic output : hex = he + qchs Paris heating network : 0,432 (T = 240°C and Ta = 20°C) Incineration : 33 to 38% towards waste LHV 38 to 45% towards boiler steam Methanisation : 39,8% towards waste LHV 53,5% towards methane

  24. Conclusion • delicate comparison because of : • different value for burnt and methanised waste • different value for steam and electricity • exergy = solution ? • similar quality measure for waste ?

More Related