基于烧失量分析的水体悬浮物浓度测量方法改进

Improved Methods for Measuring Suspended Matter Concentration in Water Based on the Analysis of Loss on Ignition

烧失量(Loss on ignition)法可以完成悬浮物中有机悬浮物和无机悬浮物的分离过程。然而,科学机构并没有统一的标准规范,例如煅烧温度、煅烧时长等因素都会造成各个实验室分析结果的差异。煅烧时间过长,无疑增大了工作量;时间太短,又不能充分除去有机物和水分。针对原有实验规范笼统地认为空白滤膜和过滤水样后滤膜的煅烧时长是一致的问题,文中提出了对原有实验规范的改进措施。研究的对象是滤膜在煅烧过程中的质量变化对悬浮物浓度测量的影响。利用SPSS进行One-Way ANOVA(单因素方差分析),处理同一煅烧温度(550℃)不同煅烧时长(15min,30 min,45 min,1 h,2 h,3 h,4 h)下滤膜的烧失量,显著性水平为0.05。分析结果表明:针对原有规范中所采用的,以4 h作为空白滤膜的煅烧时长,可以缩短至2 h。按照同样的方法,分别处理高有机悬浮物和高无机悬浮物浓度的水样,分析过滤水样后的滤膜在煅烧过程中的烧失量变化,进而判断合适的煅烧时长。利用该方法可在不影响结果精度的前提下提高悬浮物浓度测量的工作效率。

The separation of organic suspended matters from suspended matters is completed by the Loss on Ignition method. However, scientific institutions have no unified standard specification. For instance, factors like calcining temperature and time may lead to different analysis results among various laboratories. If the calcining time is too long, it will undoubtedly increase the workload; otherwise, the removal of organics and moisture can not be fully completed. Generally, the calcining time of blank filter membrane is thought to be consistent with that of filter membranes that have filtered water samples. However, original experimental specifications can be improved through new methods. This research focuses on the mass changes of filter membrane in the calcining process, which will influence the measurement of suspended solid concentration. This paper obtains analysis results from One-Way ANOVA combined with SPSS software. Original data refer to the Loss on Ignition of different calcining time（15 min,30 min, 45 min, 1 h, 2 h, 3 h, 4 h） under the same calcining temperature（550 ℃） and the significance level is 0.05.The analysis results show that the calcining time for blank filter membrane can be shorten to 2 h, instead of 4 h in the original specification. In accordance with the same method, it is feasible to deal with water samples of high organic suspended solid concentration and high inorganic suspended solid concentration, respectively. After filtering water samples, the variation of Loss on Ignition of the filter membranes in the calcination process is analyzed, so as to determine suitable calcining time. The results demonstrate that the method can improve the operating efficiency of measuring suspended matter concentration without affecting the result precision.