铸造型砂热解气体产物的快速检测与分析方法

Rapid Detection and Analysis Method of Pyrolysis Gas Products of Green Sand

建立了一种型砂热解气体产物的快速检测与分析方法。采用管式高温炉热解型(芯)砂,并将型(芯)砂热解后的气体产物通入到装有高精度传感器组的气室,进行实时检测。将热解前后气体浓度的最大增量作为检测结果。试验前,采用渗透管传递法检验了传感器的准确度,确保检测数据的准确性;试验后,采用格鲁布斯法剔除检测结果中离散的异常数据。利用该方法,对铸造厂普遍使用的煤粉湿型砂进行了检测验证。结果表明:使用的气体传感器满足准确度要求。检测的8组试样中,只有其中一组VOCs数据存在异常,说明该检测方法具有较好的可重复性。煤粉湿型砂检测到的热解气体中,产物除CO2外,还包括部分CO、SO2、VOCs等气体。

A method for rapid detection and analysis of gas products from sand pyrolysis was established.In this method,a tubular high temperature furnace was adopted to pyrolyze the green sand,and the pyrolysis gas products of green sand were passed into the gas chamber equipped with a high-precision sensor group and then detected in real time.The maximum increment of gas concentration before and after pyrolysis was taken as the detection result.Before the experiment,the accuracy of the sensor was checked by the permeation tube transfer method to ensure the accuracy of the test data.After the experiment,the Grubbs method was used to eliminate the discrete abnormal data in the test results.Using this method,the green sand commonly used in foundries was tested,and the results showed that the gas sensor used meets the accuracy requirements.And only one of the eight groups of samples tested had abnormal VOCs data,indicating that the detection method has good reliability.Among the pyrolysis gas detected by green sand,the products include CO,SO2,VOCs and other gases besides CO2.