Micro reactor application for the Beckmann rearrangement to epsilon-caprolactam

Mass and heat transfer can put significant technological limitations to reactor and process design, which leads to far from ideal solutions for bulk processes. A discussion covers the design, construction, and testing of a single channel micro reactor integrated with a micro mixer to demonstrate the viability of a miniaturized reactor system for an industrial bulk process, based on micro reaction technological considerations; model reaction used, i.e., Beckmann rearrangement of cyclohexanone oxime to epsilon-caprolactam with oleum as a catalyst and solvent; the reaction mixture (consisting of caprolactam and oleum) as the key step in the industrial process; window of operation; critical parameters in mass transport models; and the creation of multi micro zones of oxime and oleum rich phases. This is an abstract of a paper presented at the 42nd Loss Prevention Symposium (New Orleans, LA 4/6-10/2008)

Real-time feedback control system for ADITYA-U horizontal plasma position stabilisation

The ADITYA-U tokamak (R-0 = 0.75 m, a = 0.25 m) is designed to shape plasma column in both single and double null diverter configurations. It is quite well known that sustaining a shaped plasma in tokamak requires very good plasma column position control, both horizontal and vertical. An FPGA-based proportional-integral-derivative (PID) control system has been designed and operated to achieve horizontal plasma position control in ADITYA-U tokamak. The complete system has been rigorously tested with sample signals before implementing to the ADITYA-U plasma discharges. The control system is integrated and time-synchronized with the plasma discharge operation of ADITYA -U. Furthermore, the system has been trained to take appropriate actions during the disruption or plasma failure in the tokamak operation. Detailed experimental results have been obtained by the operation of the digital PID controller. The complete design, installation, operation, tuning of the system along with all the relevant testing and operating experience of the digital PID controller for real-time horizontal plasma position control is presented in the paper.SP