利用电容层析测量煤粉浓度的实验研究

锅炉燃烧过程中,准确测量风管中的煤粉浓度并指导调节对锅炉的安全、经济运行非常重要。采用电容层析成像技术,对常温下稀相气力输送的固体浓度进行了测试研究。为克服电容传感器敏感场的不均匀性对成像造成的影响,实验系统中装置了一旋风分离装置,通过旋风分离作用将固体颗粒主要集中在壁面区域,传感器电极布置在分离器直管上。这种测试方法的优点在于不破坏原有系统的运行特性,属于非侵入式、在线的快速测试技术。通过建立实验台及相应的在线测量系统,实验结果表明该法是可行的。

An Experimental Study of Pulverized Coal Concentration Measurement by Using Capacitance Tomography

The accurate measurement of pulverized coal concentration in air pipes and its proper regulation are very important to the safe and cost-effective operation of a boiler during its combustion process.By using the capacitance tomography,tested and studied was the concentration of solid conveyed by a dilute-phase pneumatic force at a normal temperature.To overcome the impact of the nonuniformity of the sensitive field of a capacitance sensor on the image formation,a cyclone separator was set up in the test system.The role of the cyclone separator is to concentrate the solid particles mainly in the wall-surface zone with the electrodes of the sensor being located on the straight pipe of the separator.The advantage of the above testing method consists in its not demolishing the operating characteristics of the original system.The method pertains to a non-intrusive type of on-line quick testing technology.The test results obtained from the test stand and relevant on-line measuring system show that the method under discussion is feasible.