Abstract The load response rate of the circulating fluidized bed (CFB) boiler is low for its great thermal inertia. In order to increase its load response rate, a new dynamic combined combustion technology featuring co-combustion of CFB coal and pulverized coal (PC) with high gross calorific value (GCV) is put forward. This combined combustion system was set up on a 240 t/h CFB boiler, and PC coal spraying positions, heating values, and heat ratios were evaluated for their effects on load response rate and combustion performance of the CFB boiler. When PC coal is fed from the secondary air pipes, the relative load change rates (RLCRs) exceed 2.0%/min and meet the requirement RLCR for power dispatching (1.5%/min), and the maximum RLCR is 3.69%/min. Moreover, the weighted average of carbon in residue decreases, and the original NOX emission of CFB boiler increases less than 40 mg/Nm3. Results indicate that the dynamic combined combustion of CFB coal and PC coal with higher GCV fed through secondary air pipes in CFB boiler is a feasible technology to increase its relative load response rate.

中文翻译：

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CFB锅炉PC煤与CFB煤动态联合燃烧下负荷响应率试验研究

摘要 循环流化床（CFB）锅炉热惯性大，负荷响应率低。为提高其负荷响应率，提出了一种以CFB煤与高总热值（GCV）煤粉（PC）混合燃烧为特征的新型动态联合燃烧技术。该组合燃烧系统设置在240 t/h CFB锅炉上，评估PC喷煤位置、热值和热比对CFB锅炉负荷响应率和燃烧性能的影响。二次风管送入PC煤时，相对负荷变化率（RLCRs）超过2.0%/min，满足电力调度RLCR要求（1.5%/min），最大RLCR为3.69%/min。此外，残渣中碳的加权平均值降低，循环流化床锅炉原NOX排放增加小于40mg/Nm3。结果表明，通过循环流化床锅炉二次风管供给的具有较高GCV的CFB煤和PC煤的动态联合燃烧是提高其相对负荷响应率的可行技术。