Hydrolysis is the most critical stage in high solids Temperature Phased Anaerobic Digestion (TPAD). In this paper two different Organic Fraction of Municipal Solid Waste (OFMSW) types were tested in co-digestion with Digested Sludge (DS) at different temperatures: 37, 55 and 65 °C. Volatile fatty acids (VFAs), soluble chemical oxygen demand (CODs) and Biochemical Methane Production (BMP) were measured and calculated after 0, 24, 48 and 72 h hydrolysis. The results showed that both the BMP and the methane production rate improved. A Solids Retention Time (SRT) of 72 h at a temperature of 55°C gave the best results: the reaction rate constant k was 0.34 d -1 and the BMP was 250 mLCH4/gMV, which were 47% and 19% higher compared to the reference (0 h hydrolysis). The CODs and VFAs profiles during hydrolysis showed how OFMSW initial characteristics can affect the performance of temperature phased anaerobic digestion.

Mixing of viscous non‐Newtonian fluids plays an important role in many industrial processes (wastewater treatment, methanization, etc.). In some cases, mixing by gas injection can be more interesting than mechanical mixing. The present study focuses on the gas injection in yield stress fluids. The influence of the air flow rate, fluid rheological properties, and geometrical configuration on an air jet impinging the bottom wall of a tank containing a yield stress fluid has been considered. Focus has been placed on the air cavity present at the injection point. The trends of two key parameters of the cavity have been characterized: its maximum diameter and frequency detachment. Correlations based on the characteristic dimensionless numbers governing the flow have been derived. These correlations show that the apparent viscosity has an effect on the cavity's frequency but a low influence on its diameter which is mainly governed by the air flow inertia.

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A two reaction synthesis of a urea, using triphosgene, was studied. The objective was to transpose the process from laboratory scale to pre-industrial plant. The whole study was performed in a continuous process, adapting the characteristic dimensions and length of the reactor. In this paper, the development of the process is presented, and the choices about safety and operating conditions constraints are discussed. The final operation allows a 70% global yield in a 7 week study. Furthermore, the use of microreactors not only permits an exhaustive study of the process operating parameters, but also provides feedback on the developed chemistry itself. The results obtained are a demonstration of the use of continuous processes in small scale reactors for complex molecule development. The mg · h -1 to kg · h -1 is a key transposition in the pharmaceutical industries project development, as it can help to accelerate the first lot production used in toxicological or pre-clinic stages.

Kinetics is essential for chemical reactor modelling, in particular to reduce the inherent risks of extrapolation going along with scaling-up. Pharmaceutical industries are especially concerned. However, when chemical systems are very complex, development of good models may lead to prohibitively expensive and time consuming experiments. The aim of this paper is to describe an efficient experimental design strategy for discrimination of stoichiokinetic models. The proposed methodology is based on model-based experimental design (optimal design), which uses information already acquired on models to determine the best conditions to implement a new experiment with the highest discrimination potential. The combination with microreactor technology is also proposed in this work. The whole procedure for model discrimination is firstly described in detail and then, applied to a numerical study case, consisting of a chemical synthesis carried out in a microreactor. The discrimination procedure efficiently leads to the determination of the single adequate model among the various potential models proposed before the implementation of the designed experiments. It is verified that the procedure does not depend on the set of preliminary experiments and is time-saving when compared to a classical factorial plan. * Corresponding author. 100-500 for Phase II and 1000-5000 for Phase III. The drug is finally submitted to regulatory agencies for evaluation and registration before commercialization. Chemical development and drug production follow each development step and must meet the requirements for the drug by scaling up manufacturing. The complexity of phenomena (chemical reactions, hydrodynamics, heat and mass transfers) limits the amount by which laboratory production methods may be extrapolated, consequently the scaling-up can lead to the unexpected degradation of product quality and formation of by-products. The development of kinetic models, and more generally of phenomenological models, is a way to ensure reliability in extrapolation and process modelling. However, the complexity of reaction systems