[en] Optimisation is essential in today's modern industrial and chemical process industries to increase efficiency and decrease downtime and maintenance costs. Such procedures can range from on-line inspection for the measurement of multi-phase flow, phase velocities, packing and conglomeration to fundamental modelling of flow behaviour to better understand the nature of fluid flow and therefore aid improved design. X-ray tomography is being developed to address these issues both on the microscopic level to characterise and quantify unit cell parameters and the macroscopic level for real time measurement of multiphase flow. The behaviour of macroscopic flow can be predicted using complex simulations however any model is only as good as the input data. Three dimensional x-ray micro-tomography with 100 micron resolution has been developed and could be used to obtain a description of the unit cell, for example volume fractions, contact surface area and particle size distribution and used as basic data for finite element modelling of macroscopic systems. Additionally a high speed x-ray tomography instrument is being developed to measure on-line multiphase flow in fast moving systems. Conventional x-ray tomography is impractical in high speed industrial applications because of the need to rotate either the source/detector assembly or the object. This new system comprises no moving parts and is expected to operate at up to 50 frames per second. The program includes the development of the x-ray source, the detector system, the electronics for data acquisition, the on-line image reconstruction and data analysis. In addition to a practical implementation of this system in an industrial environment it can also be used as a cross-validation of the macroscopic models. Details of each system will be described and the suitability of the applications discussed. (author)