自由空间反射法检测飞灰含碳量的实验研究

Experimental research on measuring carbon content of fly ash by free space reflection method

为了提高微波法检测飞灰低含碳量的灵敏度,提出了一种静态条件下检测飞灰低含碳量样品的新方法,测试频段为9.84-15 GHz。详细说明了测试的基本原理及方法,利用时域门等技术,结合5个电厂灰样含碳量为0%-20%范围内的测试结果进行分析,分别得出飞灰含碳量与幅值衰减、线性幅值之间存在的规律。经线性拟合后,在9.84-11 GHz频段时,除某厂灰样具有特殊性外,其余4个厂拟合度大于0.97。另外,在高含碳量时采用不同处理方式得到完整的测试结果。测试结果表明,与自由空间传输法相比,反射法可以解决低含碳量测试灵敏度低的问题。

To improve the sensitivity of microwave method to detect low carbon content of fly ash, this paper proposes a new method for testing the low carbon content of fly ash under static conditions. The testing frequency range is between 9.84-15 GHz. The basic principle and test method of the test are described in detail. By using the technology of time domain gates and combining the test results of different ash samples from five power plants in the range of 0%-20% of carbon content, the regular pattern of fly ash′s low carbon content and amplitude attenuation and linear amplitude are obtained respectively. By linear fitting, between the 9.84-11 GHz frequency band, the fitting degree of the other four factories is more than 0.97 except for the particularity of a factory′s ash sample. In addition, different methods are used to obtain complete test results of high carbon content. Comparing with free-space transmission method, test results show that the reflection method can solve the problem of low sensitivity of testing low carbon content.