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The objective of this work was to investigate NOxremoval with a hybrid system consisting of a DC corona discharge and a molecular sieve at a room temperature (22 °C). In the hybrid reactor a positive DC corona discharge was generated between a hollow needle and a flat mesh. A gas mixture of N2(80%): O2(5%):CO2(15%):NO(200 ppm), simulating a flue gas, flowed through the tube with a flow rate of 1 l/min. The obtained results showed that due to adsorption of NO2, resulted from NO oxidation, by molecular sieve placed in the corona discharge region, NOxremoval increased significantly. It was also found that the number of NO molecules oxidised into NO2does not depend on initial NO concentration. Thus, in the presence of the molecular sieve in the discharge region, the removal of NO is not controlled by gas phase chemical kinetics but by surface processes.

Artificial neural networks are powerful in representing nonlinear processes, but they may not be reliable when they are applied beyond their range of experience. In order to avoid suspect predictions, appropriate extensions must be installed which monitor their reliability. When their performance becomes unsatisfactory, a sufficient safety measure must be provided. A software tool is described, in which these aspects of improving artificial neural nets are implemented. Application examples are presented from a production scale beer brewery fermenter.

Hybrid process models, which simultaneously utilize artificial neural networks, fuzzy rule systems, and mathematical balance equations, are shown to improve industrial-scale biotechnical production processes. As an example the application of hybrid models to the repeated fed-batch production of a recombinant therapeutical protein from mammalian cells will be discussed. State estimation, prediction and on-line determination of optimal feeds will be considered.

The objective of this work was to investigate NOxremoval with a hybrid system consisting of a DC corona discharge and a NH3-saturated molecular sieve at a room temperature (22 °C). In the hybrid reactor a positive DC corona discharge was generated between a hollow needle and a flat mesh. A gas mixture of N2(80%):O2(5%):CO2(15%):NO(200 ppm), simulating a flue gas, flowed through the tube with a flow rate of 1 1/min. The obtained results showed that the presence of NH3as adsorbed on the molecular sieve increased NOxremoval from 60 % to 75 %. Due to NH4+ions formed on the molecular sieve surface NOxare converted into N2and H2O, i.e. the same harmless products as in the classical Selective Catalytic Reduction method which requires high temperature.