Process tomography for real-time process analysis
The Process tomography systems from Industrial Tomography Systems (ITS) enable the continuous measurement and visualization of processes within pipelines, vessels, reactors, and process columns. Unlike conventional point-measurement methods, tomography provides information about the spatial distribution of substances and phases across the entire measurement cross-section.
This allows complex processes such as mixing operations, multiphase flows, separations, or level and interface profiles to be investigated in real time. The measurement data obtained provide direct insight into processes that are normally not visible from the outside.
ITS has been developing electrical tomography systems for industrial applications and research for over 25 years. The systems can be adapted to different process geometries and measurement tasks.
Electrical Resistance Tomography (ERT)
The Electrical Resistance Tomography (ERT) – electrical resistance tomography – is particularly suitable for processes with an electrically conductive continuous phase.
Multiple electrodes capture electrical measurements around the process cross-section. Based on the varying conductivities within the medium, a tomogram is then reconstructed that visualizes the spatial distribution of the process components.
ERT is suitable, for example, for investigating:
- mixing and homogenization processes
- liquid-liquid and solid-liquid systems
- multiphase flows
- Suspensions and slurries
- crystallization and separation processes
- Filtration
- Interfaces and levels
- Process development and optimization
The strength of the method lies in particular in its dynamic real-time rendering the processes inside a container or a pipeline.
Electrical Capacitance Tomography (ECT)
The Electrical Capacitance Tomography (ECT) – electrical capacitance tomography – uses differences in the permittivity of the materials involved, making it particularly suitable for non-conductive media.
Typical applications include, for example, powders, oils, gases, and other non-conductive material systems. The sensors can be arranged outside the process wall, which also makes ECT attractive for applications where no direct contact between the electrodes and the process medium is desired or possible.
ERT and ECT complement each other very well in this way: Depending on the electrical properties of the materials involved, the respective suitable measuring principle can be chosen. For demanding applications, there are also Dual-modality systems of ERT and ECT possible.
From measurement signal to tomogram
The electrical measured values recorded by the sensors are processed by the data acquisition system and converted into a using mathematical reconstruction methods two- or three-dimensional tomogram converted.
This creates a spatial representation of the conductivity or permittivity distribution within the process. Changes can be tracked continuously and used, for example, for process development, quality assurance, or process control.
ITS systems go beyond mere visualization: the process data obtained can be used to track process parameters, assess system states, and purposefully optimize production processes.
Advantages of ITS process tomography
- Real-time measurement
- Spatial instead of merely point-based process information
- Visualization of otherwise invisible processes
- Suitable for dynamic processes
- ERT for conductive media
- ECT for non-conductive media
- Sensors individually adaptable to process and geometry
- Application from research systems to industrial process monitoring
- Possibility of integrating the measurement data into the process control
Manufacturer
Industrial Tomography Systems (ITS) based in Manchester, has been developing electrical tomography systems for industry and research for over 25 years. The company originated as a spin-off from the University of Manchester and the University of Leeds and is one of the pioneers in the commercial application of Electrical Resistance Tomography (ERT) and Electrical Capacitance Tomography (ECT).
