微波炉快速测定城市污泥湿度的探讨

用额定电压为220 V、振荡频率为2 450 MHz、输出功率为800 W的微波炉对5～30 g城市污泥辐照2～30 min。由不同时间对城市污泥进行微波辐照后的质量损失率、残余湿度以及挥发性固体（VS）含量的变化表明：用微波炉可简便、快速地测定城市污泥的湿度。为提高微波炉测定湿度的准确性，应减少取样量，进行重复辐照，并根据相邻2次辐照导致的质量变化幅度逐次缩短辐照时间；在辐照过程中应避免引起样品突然释放大量VS，辐照至恒重为止。

Study on rapid determination of moisture content in sewage sludge by microwave oven

It is indicated with loss rate of weight, remaining moisture content and volatile solid content of sewage sludge dried by microwave oven with rated voltage of 220 V, frequency of 2 450 MHz, output power of 800 W, that microwave oven can be conveniently used to rapidly determinate the moisture content of sewage sludge. To improve the veracity of the moisture content measured by the oven, the weight of a sample should be reduced and irradiated repeatedly with short period of time. The irradiation time should be shortened little by little according to the change of the weight loss between two consecutive irradiations. The irradiation process, during which the volatile solids can not be released suddenly in great amount, should be stopped as soon as the weight of sample is constant.