This 2009 paper written by experts from ORNL and CNEN contains a good summary or uranium conversion:

2. TECHNICAL PROCESS FOR NATURAL URANIUM CONVERSION PLANTS

A generic production process for natural uranium conversion normally begins with yellowcake dissolution in nitric acid, followed by a solvent extraction and purification process, followed by a concentration process in an evaporator. These are three common stages to almost any NUCP. Then, one of two main routes may be followed depending on the size of the conversion plant. For small plants (approximately 100–700 MTU/year), precipitation to ammonium diuranate (ADU), ammonium uranyl carbonate (AUC), or uranyl peroxide (UO4uranium dioxide (UO) is followed by calcination to 2). These staged processes are typically operated in batch rather than continuous mode. For medium (>1000 MTU/year) and large (>10,000 MTU/year) plants, a thermal denitration process to convert UN into uranium trioxide (UO3) or triuranium octaoxide (U3O8) is followed by an oxide reduction process to produce UO2. Then regardless of the size of the plant, the UO2 is hydrofluorinated to uranium tetrafluoride (UF4) using hydrogen fluoride (HF). The UF4 can then be fluorinated into uranium hexafluoride (UF6) using fluorine or reduced into uranium metal using magnesium and heat. The simulation of the process is performed using FLOW (a simulation program developed at ORNL).