In situ characterisation of liquids in decommissioning environments by LIBS

液体废物流和处置池是核退役挑战的关键部分。因此，这些环境的特征是一个重要方面，采样和离线分析是常规方法。本项目旨在利用激光诱导击穿光谱(LIBS)对这些环境进行原位表征，它可以提供快速的元素分析。我们已经通过从液体表面进行测量，在AFPC-PYPROGING项目中成功地对熔盐进行了初步测量，但关于采样是否代表整体以及通过将多变量数据分析和机器学习应用于导出的光谱，仍有更多的问题需要回答。我们计划通过比较“DIP-Stick”采样和在DIP-Stick上直接测量LIBS来探索代表性采样，以及开发LIBS探头来直接采样液体大块。后者将在最初开发，并在环境温度环境中进行试验。将与电感耦合等离子体离线测量的提取样品进行比较。LIBS水下或熔盐探头的测量特别具有挑战性，我们将建立在我们实验室为Torone项目(www.torone-project t.com)上的机器人应用而打造的定制LIBS和拉曼系统的经验基础上。该项目将利用NNL LIBS仪器，并设在NNL Workington的CINDE实验室。

Liquid waste streams and disposal ponds are key parts of the nuclear decommissioning challenge. Consequently, characterisation of these environments is an important aspect with sampling and off-line analysis being the conventional approach. This project aims to investigate the in situ characterisation of these environments using laser induced breakdown spectroscopy (LIBS) which can provide rapid elemental analysis. We have demonstrated success in preliminary measurements on molten salts in the AFPC-pyroprocessing project by measuring from the liquid surface but there are further questions to answer regarding whether the sampling is representative of the bulk as well as by applying multivariate data analytics and machine learning to the derived spectra. We plan to explore representative sampling by comparing 'dip-stick' sampling and direct LIBS measurement on the dip-stick as well as the development of a LIBS probe to directly sample the liquid bulk. The latter would be initially developed and trialled for ambient temperature environments. Comparisons will be made with extracted samples measured off-line by ICP. LIBS underwater or molten salt probe measurements are particularly challenging and we will build on the experience of the bespoke LIBS and Raman systems that we have built in our laboratory for robotic application on the TORONE project (www.torone-project.com). The project would make use of the NNL LIBS instrument and be based at NNL Workington in the CINDe laboratory.