A New Agro/Forestry Residues Co-Firing Model in a Large Pulverized Coal Furnace: Technical and Economic Assessments

Energies

Weigang Xu²  Yanqing Niu¹  Houzhang Tan²  Denghui Wang²  Wenzhi Du² 

[1] Ministry of Education (MOE), Key Laboratory of Thermo-Fluid Science and Engineering, Department of Thermal Engineering, School of Energy and Power Engineering, Xi’an Jiaotong University, Shaanxi 710049, China;

关键词: co-firing;    agro/forestry residues;    mill;    CO₂/NO_x/SO₂;    boiler efficiency;    fly ash;    cement characteristics;    economic assessment;   

DOI  :  10.3390/en6094377

来源: mdpi

【 摘 要 】

Based on the existing biomass co-firing technologies and the known innate drawbacks of dedicated biomass firing, including slagging, corrosion and the dependence on fuel, a new model of agro/forestry residue pellets/shreds and coal co-fired in a large Pulverized Coal (PC) furnace was proposed, and the corresponding technical and economic assessments were performed by co-firing testing in a 300 MW PC furnace and discounted cash flow technique. The developed model is more dependent on injection co-firing and combined with co-milling co-firing. Co-firing not only reduces CO₂ emission, but also does not significantly affect the fly ash use in cement industry, construction industry and agriculture. Moreover, economic assessments show that in comparison with dedicated firing in grate furnace, agro/forestry residues and coal co-firing in a large PC furnace is highly economic. Otherwise, when the co-firing ratio was below 5 wt%, the boiler co-firing efficiency was 0.05%–0.31% higher than that of dedicated PC combustion, and boiler efficiencies were about 0.2% higher with agro/forestry residues co-firing in the bottom and top burner systems than that in a middle burner system.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.