高精度智能定硫仪的设计

Design of accurate intelligent sulfur determination device

为了测量煤中硫的含量,设计了基于库仑滴定法的高精度智能定硫仪。对智能定硫仪的结构和工作原理进行了介绍,重点分析了仪器的数据采集模块、电解电流控制模块和炉温控制模块。该仪器采用12位串行A/D转换器对4路输入信号进行采集,通过冷端补偿和PID控制实现了炉温的高精度测量与控制,并采用D/A转换器对电解电流进行精确控制,最后对测量数据的精密度和准确度进行了检验。测试结果表明,用该仪器测量低硫煤时标准偏差为0.012%,测量高硫煤时标准偏差为0.027%,精度远高于国家标准。

An accurate intelligent sulfur determination device based on Coulomb titration method was designed to measure the contents of sulfur in coal. The configuration and working principle of the sulfur determination device is introduced in this paper. The main modules of the device such as data acquisition module, electrolytic current control module and furnace temperature control module are analyzed emphatically. A 12 bit serial A/D converter is adopted in this device to collect four input signals. The furnace temperature is measured and controlled accurately through cold end compensation and PID control. The electrolytic current is controlled accurately by a D/A converter. Ultimately, the precision and accuracy of the measurement data are verified. Test result proves that the measurement standard deviation is 0. 012% when it is used to measure coal with low sulfur content, and is 0.027% for coal with high sulfur content. The measurement accuracy is much better than the requirement of national standard.