CRUD (Chalk River Unidentified Deposit) forms in the water circuits of nuclear reactors due to corrosion of structural materials and the consequent release of species into the coolant. The deposition of CRUD is known to occur preferentially in regions of the primary circuit of pressurised water reactors (PWRs) where the water flow accelerates. In order to investigate this phenomenon, a micro-fluidic system, recreating plant conditions while using a simplified experimental set-up, was realised. A flow cell, comprising a stainless steel disc with a central micro-orifice, was used to create accelerated flow under representative operating conditions. By monitoring the pressure drop across the cell, the build-up rate (BUR) of CRUD within the micro-orifice was monitored in real time. By this setup, the conditions inducing deposition of CRUD under PWR conditions were emulated and CRUD deposition was induced in the accelerated flow region. Further effects associated with the presence of lithium hydroxide were investigated in real-time.

由于结构材料的腐蚀以及随之而来的物质释放到冷却剂中，CRUD（粉笔河未确认沉积物）在核反应堆的水循环中形成。已知CRUD的沉积优先发生在水流加速的压水反应堆（PWR）主回路的区域中。为了研究这种现象，实现了一种微流体系统，该系统在使用简化的实验装置的同时重新创建了工厂条件。流通池包括具有中心微孔的不锈钢圆盘，用于在代表性的运行条件下产生加速的流动。通过监控整个电池的压降，可以实时监控微孔内CRUD的堆积率（BUR）。通过此设置，模拟了在PWR条件下引起CRUD沉积的条件，并在加速流动区诱导了CRUD沉积。实时研究了与氢氧化锂的存在有关的进一步影响。