Hydrodynamic and combustion behavior of low grade coals in the riser of a circulating fluidized bed combustor

Ahmad Hussain, Faraz Junejo, Muhammad Nauman Qureshi, Afzal Haque

Abstract


This study is conducted for understanding the fluidization conduct in a CFB circle for poor quality coals. A lab-scale cold CFB test rig was built at the NFCIET Multan for picturing the fluidization conduct. Impacts of channel air on the fluidization conduct were tentatively explored. It was discovered that speed shapes along the riser tallness is affected by the leave geometry. The combustion behavior of low grade coals from. Thar coal was additionally explored in a CFB Combustor. The impacts of the essential air and sustain rate were examined and their effect on outflows has been set up. The temperature at the highest point of the CFB expanded quickly to around 900°C. This expansion in temperature has caused an increment in the thickness of gasses with temperature which in this way made the suspension thickness increment. From this exploration, a firsthand experience of consuming poor quality coals from Pakistan was illustrated.


Keywords


: circulating fluidized bed (CFB); combustion; fluidization; hydrodynamics; low grade coal; temperature profile.

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DOI: http://dx.doi.org/10.24949%2Fnjes.v11i1.436

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ISSN (Print): 2070-9900   ISSN (Online): 2411-6319