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This work presents a mathematical tool to estimate the cost of fabricating pumps by traditional casting. The drivers that most affect the cost of the process are identified in each step of the procedure, i.e., material, labour, energy, tools and general expenses associated with any industrial activity. The mathematical expressions used for the calculation of the different cost drivers are presented and used to estimate the cost of fabricating the different parts composing a radial pump in a small Moroccan foundry. Therefore, the input data of the equations carefully consider the economic factors of this country. However, the developed tool is versatile and can be adapted to describe the casting process in other countries with different economies just by changing the input data accordingly. It is observed that the influence of the drivers in the final cost of the pump is very dependent on the number of pumps to be produced. In any case, the cost estimation tool presented in this work will allow for the optimization of the yield of the casting process rendering the involved company more reliable. The tool provides an idea of the implications of changing production factors, allowing the foundry to give accurate and fast responses without compromising its profits.

Numerous adsorbent materials are developed and are able to face specific types of pollution, but none of them can manage the whole pollution. The purpose of this work is to develop a novel hybrid adsorbent, based on chitosan (CS) biopolymer, clay minerals and activated carbon (AC), having complementary adsorption properties and achieving a wide-spectrum water decontamination in a single treatment. Hybrid CS beads, containing dispersed clay and AC, were prepared from dispersions of solid adsorbents in a CS solution and its further coagulation in a basic medium. The porosity and the homogeneity of the hybrid beads were characterized by N2 adsorption at 77 K and Cryo-Scanning Electron Microscopy respectively. The interaction between CS and clay was characterized using X-ray diffraction. Water content and the amount of each adsorbent in the hydrogel beads were determined by thermogravimetric analysis. Such a composite material was still porous and presented a wide adsorption spectrum. As shown by their adsorption kinetics, hydrophobic anionic clofibric acid (CBA) and cationic metoprolol (MTP) were well adsorbed on AC containing beads (21 and 26 mg/g), respectively. Clays containing beads showed interesting adsorption properties towards cationic Zn2+ and MTP. The obtained composite beads were able to adsorb all the pollutant types: Zinc cations, and hydrophobic-charged organic molecules, such as pharmaceutical derivatives (clofibric acid and MTP).