粉煤灰碳含量检测仪检测算法分析

粉煤灰中未燃烧的碳的含量是粉煤灰利用的重要指标.对比研究FFT频域分析法、自相关检测法和基于互相关的虚拟数字锁相放大法3种算法检测粉煤灰中未燃烧的碳含量,结果表明,虚拟数字锁相放大法测量标准粉煤灰的碳含量所得数据更加准确可靠,相对误差和方差均较小,不超过4％,测量碳含量在0.5％～4％的粉煤灰样品时,光声信号电压值随碳含量变化的线性关系更加直观.虚拟数字锁相放大技术能够精确简单快捷地检测出粉煤灰中的碳含量,对于能源节约和环境保护意义重大.

Detection algorithm analysis on fly ash unburnt carbon detector

Unburnt carbon detection in fly ash is the key target in fly ash using.Three algorithms are comparatively studied,i.e.,FFT frequency domain analysis, autocorrelation,virtual digital lock-in amplification based on cross-correlation.Results show that the data using virtual digital lock-in amplification measurement to detect standard fly ash carbon content is more accurate and reliable,the deviation and variance are relatively smaller,less than 3%.When measuring the carbon content fly ash sample of 0.5%-4%,a linear relation between photoacoustic signal voltage and carbon content is more intuitive and clear.Virtual digital lock-in amplifier technology can detect the unburnt carbon content in fly ash accurately,simply and fastly.