Dr. ir. Leon Geers
- transport phenomena
- process intensification
- experimental data analysis
- mathematical modeling
- flow chemistry
Switching from batch to continuous flow chemistry sets requirements for analysis and control of the process in question. Special measuring methods are needed to keep the quality of the product as high as possible when producing a continuous flow of chemicals and TNO has developed technologies specifically for this purpose. Some of these technologies originated outside the field of chemistry but can be applied perfectly well.
In the classical chemical process, parameters such as temperature, pressure and rate of flow follow a predetermined programme. After the chemical reaction, a sample of the product is analysed in a laboratory. If the quality is inadequate, the entire production batch is reprocessed to realize the required product or it may even be disposed of. What is needed is measuring technology which can accurately measure the product quality during the process. If in-line analysis is used, any undesirable abnormalities can be adjusted immediately. This analysis is essential in a lot of flow chemistry. The physical limits are increasingly being stretched by innovative process technology. In flow chemistry, everything is much more precise than in the traditional batch processes of reaction and separation. The important thing is to prevent safety risks (runaway) or undesired product loss from taking place. With the aid of advanced measuring technologies, however, the process can be continuously monitored and adjusted if necessary.
A significant development in this respect is that analysis techniques traditionally applied in laboratories are now being applied increasingly in industrial chemical processes. In addition to the temperature, pressure and flow rate, also the precise composition of the product can be monitored. The formation of by-products, for example, is spotted immediately and the manufacturer can better guarantee the purity of his products. Optical measurement techniques are particularly suitable for in-line analysis. TNO has been developing applications based on optics, such as optical spectroscopy, for some time. Examples vary from measurements carried out on soil samples on the moon to blood sugar levels in diabetic patients. This optical method is ideal for monitoring chemical processes. For instance, TNO has developed process monitoring technology for continuous processes to measure concentrations of a number of compounds down to promille levels, and one particular compound down to ppm levels simultaneously.
TNO has knowledge of and experience with many different disciplines and applications. Close cooperation between people in various disciplines often leads to surprising combinations. A good example of this is found in ultrasound technology. Ultrasonic sound has a frequency above audible sound. In recent years, TNO has developed different applications using ultrasonic sound to measure wall thickness and localize leaks or corrosion in pipelines in the oil and gas industry, among other things. This technique can easily be applied as a small-scale, fully acoustic method to measure the flow rate and monitor composition in chemical processes.